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SEA => SUBS: Uboats => TYPE VII => Topic started by: tore on 29 Jan , 2012, 01:33

Title: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jan , 2012, 01:33
Upon requests and for my own convenience I am opening this thread if I can (within the limit of my capacity), be of any help to you who are taking interest in  the VIIC and VIIC/41 boats. My experience is primarely based upon my 2-3 years as the (EO) engineering officer, on the norwegian version of  U-995  KNM Kaura and U-926   KNM Kya to a lesser extent U-1202  KNM Kinn in the periode 1953- 1956.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jan , 2012, 02:02
Christopher
Your question on snorting.
Snorting was in general a challenge to the people on watch. Trim and correct handling of the hydroplanes was very important.
If the snortvalve shut,  the big diesel would suck out the air in the sub in seconds and the people would suffer. The cook had a hard time, one minute the kettles simmered in a second it could start boiling like crazy. In my day snorting was a novelty and in order to get experience we were ordered to test out the boat by sailing submerged from the westcoast of Norway passing Iceland to Greenland and back some 27 days submerged, which at that time was a record (in the norwegian navy).
We got a lot of experience and ideas for improvement. One of the main problems was the garbage of which 46 men produce substancial in the course of 27 days. Rottening garbage is not a pleasant thing and particulary not on board a sub. We got desperate and decided to put it in bags ( before the plastic ages) and load the torpedotubes whereupon we fired. Of course the bags bursted and the torpedopeople didn`t like it much
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jan , 2012, 02:22
Christopher
Painting the casing
No we didn`t let the crew do any painting, we usually docked the sub every 6 month and the yard did the painting. Howewer we had a can of paint for patching up minor rustspots. Remember space was limited. It was more important to have place for some cases of whisky. Some times I wonder if the popular weathering of the modelsubs is a little overdone allthough the wartime uboots did looked a little weary after a warpatrol. The blackening of the casing at the exhaustoutlet in the casing is overdone.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Jan , 2012, 16:45
Tore, have you seen this web site?

http://www.kubische-panoramen.de/index.php?id_id=5373&p= (http://www.kubische-panoramen.de/index.php?id_id=5373&p=)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2012, 00:20
Unbelievable! I have never seen it, you can really see every detail. I shall definetely study the pictures a little closer.
I see they have done a little fancy painting on the engines since  my time and unfortunately even painted parts which shouldn`t be painted f.i. the fuelcontrolrods of the fuel pumps. Great! I shall have interesting days ahead of me. Thanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Jan , 2012, 02:44
Unbelievable! I have never seen it, you can really see every detail. I shall definetely study the pictures a little closer.
I see they have done a little fancy painting on the engines since  my time and unfortunately even painted parts which shouldn`t be painted f.i. the fuelcontrolrods of the fuel pumps. Great! I shall have interesting days ahead of me. Thanks.
Tore

Tore, do you mean that dark blue was not the original colour. I am shock to found this out!  ;) ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Jan , 2012, 02:56
Colour coding for Piping

How common was the colour coding on the different piping system throughout the U-boat? Can you remember any of the colours?
 
We have a set of original German piping Schematics drawings that show the colour coding for each pipe (e.g. Gray with two brown bands = High Pressure Air for blowing or Purple with blue band = Oil purifying system piping).
 
However, it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2012, 04:40
Unbelievable! I have never seen it, you can really see every detail. I shall definetely study the pictures a little closer.
I see they have done a little fancy painting on the engines since  my time and unfortunately even painted parts which shouldn`t be painted f.i. the fuelcontrolrods of the fuel pumps. Great! I shall have interesting days ahead of me. Thanks.
Tore

Tore, do you mean that dark blue was not the original colour. I am shock to found this out!  ;) ;)
The main engines were grey. The camshaftrods to the rockearms were not painted at all (metalic), the controlrods to the fuelpumps were not painted, the indicatorcocks black( not painted), and as far as I can remember the HP fuelpumps  were black.The small drains (dearation) on the fuelpumps same as the pump, not red. I`ll revert to the other question later today.
Tore.   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2012, 07:05
You may see a more correct picture of the enginecolours at Wikipedia Commons Filmset of das Boot, Wikipedia file: Bavaria filmstudio das Boot. Correct not painted fuelcontrolrods,camshaftrods for exhaust and inletvalves indicators cocks and engine colours on fuelpumps. May be a little too rusty on the nonpainted parts. Hope this don`t give you any trouble.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2012, 07:34
Colour coding for Piping

How common was the colour coding on the different piping system throughout the U-boat? Can you remember any of the colours?
 
We have a set of original German piping Schematics drawings that show the colour coding for each pipe (e.g. Gray with two brown bands = High Pressure Air for blowing or Purple with blue band = Oil purifying system piping).
 
However, it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2012, 00:05
Hi again,
I found a photo of Kauras engines, although it is black and white and bad quality, you can see the shiny steel pushrods for the valverockers and (not so clearly) the steel fuel regulatingrods not painted. On the pipes up front you migth be able to see some colourmarking bands. 
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2012, 00:24
Hi again,
I found a photo of Kauras engines, although it is black and white and bad quality, you can see the shiny steel pushrods for the valverockers and (not so clearly) the steel fuel regulatingrods not painted. On the pipes up front you migth be able to see some colourmarking bands. 
Tore

Tore, were the fuel line bronze?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2012, 04:43
I think they possibly were, but
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 05:32
Model KNM Kaura ( U 995  VIIC/41) norwegian version.
My model was finished today and as some of you asked me to show a picture of my modest model. I am posting same, although it is not so much compared to what some of you are building. The model is in general based on the Revell building kit with addition of the normal varieous "extras" brass, wood and decalsets as far as they were correct. The model kit is modified on several places: guns and wintergarten removed, partly new conningtower, snortmast modified incuding new airpiping,deckcasing and lockingpin. Casingdeck modified, two pressurecontainers ( not 4), casingdeckflares (widening) at the wintergarten place removed and casing straigthened, zinkanodes ( not painted)on the propellor "A"brackets and aft hydroplanes and slit for the"Pillenwerfer" on stb side next to the exhaust outlet to mention a few things. The model is painted to the norwegian navys colourcodes and not weathered as the sub  never looked  like some of the fantastic and skillfully made weathered modelsubs you see, neither is any brownwash done whereby you emphasize the rivets of any use as you hardly notice same in the real.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 01 Feb , 2012, 05:52
A Fine looking ship Sir!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 06:00
The lower picture is a try to show the opened ballast tank bottomflapvalves with double valverods.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 01 Feb , 2012, 09:25
Tore -
I have a question for you about the KNM Kaura - when standing topside on deck, looking down to the torpedo loading hatches, were there bulkheads, perhaps with limber holes, boxing in the hatch and well, or was it open framework? Do you have any pics of that area of the ship?
I found this picture of the White Ensign Models brass PE set, but would like to know if the loading well on Kaura looked like that.
http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg (http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg)
Also, was the snort well boxed in as well, or was there just framework supporting the deck around the snort.
Thanks!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 10:53
Tore -
I have a question for you about the KNM Kaura - when standing topside on deck, looking down to the torpedo loading hatches, were there bulkheads, perhaps with limber holes, boxing in the hatch and well, or was it open framework? Do you have any pics of that area of the ship? Also, was the snort well boxed in as well, or was there just framework supporting the deck around the snort.
Thanks!
Christopher
Christopher
I don`t think there were any bulheads, but as usual on subs to strengthen the pressure hull,  where you had a weak spot as the case for the torpedoloadinghatches (oval openings), you put in case of the VIIC`s strengthening beams resting in racks adjoining the frames. I as far as I remember the hatchhole was cut through two frames thus we had two 150-160 mm round bars which were put in having a clearance of approximately 20 mm. I checked the clearance  once on a deepdive , 100m , and the clearances at the rods was then 0.
I`m sorry I cannot find any pictures on the subject in my files.
Tore
The snort recess in the deck was not a box but as you say casingdeck supports.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 01 Feb , 2012, 11:09
Tore - It seems I was trying to add a picture I found at the same time you answered me!
http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg (http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg)


So you don't recall anything like this surrounding the torpedo loading hatch below the working deck?
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Feb , 2012, 11:43
Tore, yes a very fine looking ship  :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 11:57
Tore - It seems I was trying to add a picture I found at the same time you answered me!
http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg (http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg)


So you don't recall anything like this surrounding the torpedo loading hatch below the working deck?
Christopher
Ah now I get the question rigth. I am at a loss to  understand this WEM PE set. I was never involved in the torpedoloading. To me it doesn`t looks like any pressurehullpart but as you say a box immedeately under the deck having floodgates. I am at a loss to explain the purpose of this and cannot recall ever to have seen it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 01 Feb , 2012, 12:05
I understood what you meant about the round bars and the clearance. It is interesting to me that at 100 meters the pressure hull would compress a measurable amount like that!
But I have always wondered at the torpedo loading "box". Its frame proportions do not make any sense compared to standard VIIC and VIIC41 drawings. I am at a point where I need to design that area of my boat, so I can build the frames and pressure hull, but I want it to be as realistic as possible.
I also must design and build the well where the top head of the snort rests when it is stowed, and want that as realistic as possible also - I think there are enough pics of U-995/KNM Kaura of that area though.
Thank you once again! :-)
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 12:27
I understood what you meant about the round bars and the clearance. It is interesting to me that at 100 meters the pressure hull would compress a measurable amount like that!
But I have always wondered at the torpedo loading "box". Its frame proportions do not make any sense compared to standard VIIC and VIIC41 drawings. I am at a point where I need to design that area of my boat, so I can build the frames and pressure hull, but I want it to be as realistic as possible.
I also must design and build the well where the top head of the snort rests when it is stowed, and want that as realistic as possible also - I think there are enough pics of U-995/KNM Kaura of that area though.
Thank you once again! :-)
Christopher
Christopher I just had a look around and on the 1.72 kit of Czech Masters U-Boot VIIC winch loading torpedoes is a cutaway drawing showing the area between the casing deck and pressurehull at the forward topedoloading hatch. It`s an artist`s impression but the czech are usually very correct at the details. On this drawing I cannot see any casingbox. Have a look.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 12:44
I understood what you meant about the round bars and the clearance. It is interesting to me that at 100 meters the pressure hull would compress a measurable amount like that!
But I have always wondered at the torpedo loading "box". Its frame proportions do not make any sense compared to standard VIIC and VIIC41 drawings. I am at a point where I need to design that area of my boat, so I can build the frames and pressure hull, but I want it to be as realistic as possible.
I also must design and build the well where the top head of the snort rests when it is stowed, and want that as realistic as possible also - I think there are enough pics of U-995/KNM Kaura of that area though.
Thank you once again! :-)
Christopher
Christopher I just had a look around and on the 1.72 kit of Czech Masters U-Boot VIIC winch loading torpedoes is a cutaway drawing showing the area between the casing deck and pressurehull at the forward topedoloading hatch. It`s an artist`s impression but the czech are usually very correct at the details. On this drawing I cannot see any casingbox. Have a look.
Tore 
Snortmastrecess. I think the recess was adopted to the type of snortmast fitted on the sub. You may see something on my picture of the snortmast with electropneumatic head which had a tailormade recess. So I guess you have to decide which snortmast you`ll go for before looking for details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Feb , 2012, 13:00
 Tore, is correct. From my research every boat that has a recess in the deck for the Schnorchel mast was different. There seen to be no standard layout for the recess. Most recess follow the Schnorchel head profile, however, some are just a square shape.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 13:17
A Fine looking ship Sir!
Thanks, but it isn`t much compared to what you guys are doing. I think possibly it is one if not the only VIIC/41 in the norwegian version which is the speciality rather than anyhting else. I have ordered a glass showcase designed by me without frames where I am going to install a ledstrip illumination before I put it in the Captains Corner in my sittingroom
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Feb , 2012, 14:02
Q: Floor plating

Tore, was the floor plating in the engine room painted black or was it unpainted?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 14:36
Q: Floor plating

Tore, was the floor plating in the engine room painted black or was it unpainted?
I `m almost sure it was unpainted
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Feb , 2012, 14:55
Q: Floor plating

Tore, was the floor plating in the engine room painted black or was it unpainted?
I `m almost sure it was unpainted
Tore

Thanks  :) :)

Tore, in some very rare original war time photographs of the engine room, I have seen a mat running the full length between the two diesel engines. Did you used a mat in the walkway between the diesel engines?
 
Q: Colour
 
Was the framing painted within the engines room?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2012, 23:56
Q: Floor plating

Tore, was the floor plating in the engine room painted black or was it unpainted?
I `m almost sure it was unpainted
Tore

Thanks  :) :)

Tore, in some very rare original war time photographs of the engine room, I have seen a mat running the full length between the two diesel engines. Did you used a mat in the walkway between the diesel engines?
 
Q: Colour
 
Was the framing painted within the engines room?
Normally we didn`t have any mats on the floorplating. I guess in wartime sometimes you would have something like an oilresistant rubbermat because the plating had a tendency to make substantial noise, particulary when people are rushing to their battle/divingstations As I previously have stated, noise is the subs worst enemy, hence rubbershocks mountings, rubbercovered tools and robbermats on the floorplatings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2012, 00:01
I realised I forgot the painting question.
Yes, the frames were painted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Feb , 2012, 02:44
Hi Tore


Thank you for posting photo with you inspecting the upper deck of the U-995.


If the snortvalve shut,  the big diesel would suck out the air in the sub in seconds and the people would suffer. The cook had a hard time, one minute the kettles simmered in a second it could start boiling like crazy. In my day snorting was a novelty and in order to get experience we were ordered to test out the boat by sailing submerged from the westcoast of Norway passing Iceland to Greenland and back some 27 days submerged, which at that time was a record (in the norwegian navy).

I have found (and translated to polish) instructions for using Schnorchel on type VIIC and IX boats.
http://www.ubootwaffe.pl/okrety/wyposazenie/chrapy.html
(at the bottom of the page there are original ones)


In the one of your previous post you have written:
Quote from: tore
We never operated more than one diesel at the time and always with the propellor disengaged, chargeing the batteries.The other E-motor/generator took care of the propulsion. We tried out direct dieselpropulsion while snorting but learned that the hydroplanes and the boat was not very suitable for high speed submerged and the mast was not designed for the load.


You mentioned the diesel propulsion - I think it is suitable for the case 3 on the page
(http://www.ubootwaffe.pl/images/okrety/wyposazenie/chrapy/preliminary_snorkel_description1.jpg)


and the mode you have used is case 5 on page:
(http://www.ubootwaffe.pl/images/okrety/wyposazenie/chrapy/preliminary_snorkel_description2.jpg)


From my researches I know, that one 9-cylinder MAN engine created 20 mm Hg vacuum during snorting, but when the snorkel head valve was closed, after 2 min. the vacuum was 120 mm Hg. Did you installed any safety devices shutting off the engines autamatically when such vacuum occured?


You have also mentioned, that the electric distilling plant was not in use on board of the KNM Kaura - how did you supplement the water in battery cells? Where did you get from the water for cooking? You have used the water stored in the tanks for the whole cruise?


Was the navigation a problem during long sumberged cruises? Did you used dead reckonning? Did you use the original german Anschutz gyro compass or you have modern navigation systems?


And one more question not related with snorkeling but related to the sanitary systems - do you know if toilets on KMM Kaura where replaced or they are original/german?


We got a lot of experience and ideas for improvement.
Could you mention improvements you have implemented?


One of the main problems was the garbage of which 46 men produce substancial in the course of 27 days. Rottening garbage is not a pleasant thing and particulary not on board a sub. We got desperate and decided to put it in bags ( before the plastic ages) and load the torpedotubes whereupon we fired. Of course the bags bursted and the torpedopeople didn`t like it much
I have read that during war there were three ways:
1. launching the garbages through the torpedo tubes - not practiced because of necessity of thorough cleaning the tube and hazard of jamming the launching piston during torpedo launch.
2. launching the garbages through the BOLD ejection tube - not preferred bacause of necessity of laborious loading small parts to the tube.
3. storing the garbages on the board - most common.




And one question related to the electric equipment - for a long time I'm looking for the informations about the Batterie Selbstschalter - Battery automatic circuit breakar - located in the galley and near the commanding officer room. I have never seen the photo of such device - and for now I think that the only way is to convince the curator of the memorial in Laboe. Maybe you have some information on this topic?


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Feb , 2012, 03:07
And one more general question - how did you managed with the spare parts - during operation of the KNM Kaura you have to replace/repair used parts - did the norwegian industry make replacement parts?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2012, 05:24
Hi Tore


Thank you for posting photo with you inspecting the upper deck of the U-995.


If the snortvalve shut,  the big diesel would suck out the air in the sub in seconds and the people would suffer. The cook had a hard time, one minute the kettles simmered in a second it could start boiling like crazy. In my day snorting was a novelty and in order to get experience we were ordered to test out the boat by sailing submerged from the westcoast of Norway passing Iceland to Greenland and back some 27 days submerged, which at that time was a record (in the norwegian navy).

I have found (and translated to polish) instructions for using Schnorchel on type VIIC and IX boats.
http://www.ubootwaffe.pl/okrety/wyposazenie/chrapy.html
(at the bottom of the page there are original ones)


In the one of your previous post you have written:
Quote from: tore
We never operated more than one diesel at the time and always with the propellor disengaged, chargeing the batteries.The other E-motor/generator took care of the propulsion. We tried out direct dieselpropulsion while snorting but learned that the hydroplanes and the boat was not very suitable for high speed submerged and the mast was not designed for the load.


You mentioned the diesel propulsion - I think it is suitable for the case 3 on the page
(http://www.ubootwaffe.pl/images/okrety/wyposazenie/chrapy/preliminary_snorkel_description1.jpg)


and the mode you have used is case 5 on page:
(http://www.ubootwaffe.pl/images/okrety/wyposazenie/chrapy/preliminary_snorkel_description2.jpg)


From my researches I know, that one 9-cylinder MAN engine created 20 mm Hg vacuum during snorting, but when the snorkel head valve was closed, after 2 min. the vacuum was 120 mm Hg. Did you installed any safety devices shutting off the engines autamatically when such vacuum occured?


You have also mentioned, that the electric distilling plant was not in use on board of the KNM Kaura - how did you supplement the water in battery cells? Where did you get from the water for cooking? You have used the water stored in the tanks for the whole cruise?


Was the navigation a problem during long sumberged cruises? Did you used dead reckonning? Did you use the original german Anschutz gyro compass or you have modern navigation systems?


And one more question not related with snorkeling but related to the sanitary systems - do you know if toilets on KMM Kaura where replaced or they are original/german?


We got a lot of experience and ideas for improvement.
Could you mention improvements you have implemented?


One of the main problems was the garbage of which 46 men produce substancial in the course of 27 days. Rottening garbage is not a pleasant thing and particulary not on board a sub. We got desperate and decided to put it in bags ( before the plastic ages) and load the torpedotubes whereupon we fired. Of course the bags bursted and the torpedopeople didn`t like it much
I have read that during war there were three ways:
1. launching the garbages through the torpedo tubes - not practiced because of necessity of thorough cleaning the tube and hazard of jamming the launching piston during torpedo launch.
2. launching the garbages through the BOLD ejection tube - not preferred bacause of necessity of laborious loading small parts to the tube.
3. storing the garbages on the board - most common.




And one question related to the electric equipment - for a long time I'm looking for the informations about the Batterie Selbstschalter - Battery automatic circuit breakar - located in the galley and near the commanding officer room. I have never seen the photo of such device - and for now I think that the only way is to convince the curator of the memorial in Laboe. Maybe you have some information on this topic?


--
Thanks, regards
Maciek


Hi Maciek
Very interesting subject, I just had a very brief look on the German instructions and cannot comment to much on this stage, but it seems to me it refer to the early execution of the snort system. I return to this.
Destilled water. Yes we had containers.
Navigation. I am not a navigator, and cannot comment very detailed on this, but we didn`t have any problem and we used the original Anschutz gyro. When passing Iceland we could of course got bearings. I suppose they used stars when possible and echosounding , but I really don`t know.
Garbarge. One of our experience suggestions was to make a garbage torpedo container to use in the torpedotube. The two other options you mentioned was not not feasible to our opinion.
Experience. A suggestion to operate the diesels disengaged from propellors. Other items was more related to the people and food. For sure there were more suggestions but I can`t remember.
Toilets were the originals
Battery circuit breaker.  I don`t think I have a picture or any notes on this, everything was destroyd some 50 years ago but I `ll have a look. I`ll be back on the rest later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2012, 13:56
hi Maciek
Futher to your questions.
Dieselopereration during snorting.
We didn`t have any automatic shut down of the diesels at excessive vacum and when snorting the engineer on watch was stand by and had a hard time in bad weather. In fair weather and with a stable trim the underpressure in the sub was not really a problem,it was the variable pressure which caused the troubles.
Drinking- and cookingwater. We used water from the freshwatertanks all the time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2012, 14:18
Maciek I see I forgot to answer your question on parts.  We had sufficient spareparts from ex german stocks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Feb , 2012, 01:01
Hi Tore


Thank you for all answers.



Dieselopereration during snorting.
We didn`t have any automatic shut down of the diesels at excessive vacum and when snorting the engineer on watch was stand by and had a hard time in bad weather. In fair weather and with a stable trim the underpressure in the sub was not
really a problem,it was the variable pressure which caused the troubles.
I have read that US subs after GUPPY conversions were equipped with the devices, which shut down the engines when one a large vacuum occured, when the RPM of the engines droped down and when the exhaust gases pressure exceeded. On KNM Kaura without such facilities it had to be really hard work.


Snorting underpressure
We never operated more than one diesel at the time and always with the propellor disengaged, chargeing the batteries.The other E-motor/generator took care of the propulsion. We tried out direct dieselpropulsion while snorting but learned that the hydroplanes and the boat was not very suitable for high speed submerged and the mast was not designed for the load.

What was average cruise speed while snorting? Do I understood correctly, you mean, that accurate depth handling (necessary for snorting) was hard on greater speed?  Or the boat was generally tough to handle?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2012, 01:07
Many of the modelbuilders have got confused on the details of the forward and aft steeldecksurface on the VIIC/41,as Revell and some of the PE brass kits shows different pattern. I`m showing the original pattern as on VIIC/41 KNM Kaura ex U 995 and the ex german Uboot pen in Trondheim which became our  submarinestation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2012, 01:42
Tore, Thanks for the great picture of the bow  :) :)

From other pictures of the Type VIIC/41 bows I have seen, the steel plate along the edge looks smooth (without the small bump - like my drawing below). I was wondering on KNM Kaura was the steel plate in the centre part of the bow, as it the same pattern and type of steel plate found along the edge?

(http://img339.imageshack.us/img339/9615/new2lt.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2012, 01:52
Hi Tore


Thank you for all answers.



Dieselopereration during snorting.
We didn`t have any automatic shut down of the diesels at excessive vacum and when snorting the engineer on watch was stand by and had a hard time in bad weather. In fair weather and with a stable trim the underpressure in the sub was not
really a problem,it was the variable pressure which caused the troubles.
I have read that US subs after GUPPY conversions were equipped with the devices, which shut down the engines when one a large vacuum occured, when the RPM of the engines droped down and when the exhaust gases pressure exceeded. On KNM Kaura without such facilities it had to be really hard work.


Snorting underpressure
We never operated more than one diesel at the time and always with the propellor disengaged, chargeing the batteries.The other E-motor/generator took care of the propulsion. We tried out direct dieselpropulsion while snorting but learned that the hydroplanes and the boat was not very suitable for high speed submerged and the mast was not designed for the load.

What was average cruise speed while snorting? Do I understood correctly, you mean, that accurate depth handling (necessary for snorting) was hard on greater speed?  Or the boat was generally tough to handle?


--
Thanks, regards
Maciek
Maciek
Of course today the submarines are equipped with all sorts of sofisticated devices. In  the 40- 50- ties most of the submarines were really "divingboats". The latter part of the war was the dawn of the real sub. The VIIC`s was a "divingboat" converted to some extent, thanks to the snortmast, to a real submarine.In spite of all writingdesk instructions we, operating the thing, had to try out (and fail) various ways to get experience to handle the sub.
As far as I remember (nearly 60 years ago) the to run the diesel direct on the propellor some times made the sub a little "ticklish" and hence you to dip the snort valve too much and we exceeded the values ( we didn`t measure same) mentioned in your german instructions  ( we never did see them). resulting the underpressure to become to excessive and sometimes ( very rare) the exhaustbackpressure. It could be we exceeded the speeds mentioned in your german document.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2012, 02:01
Tore, Thanks for the great picture of the bow  :) :)

From other pictures of the Type VIIC/41 bows I have seen, the steel plate along the edge looks smooth (without the small bump - like my drawing below). I was wondering on KNM Kaura was the steel plate in the centre part of the bow, as it the same pattern and type of steel plate found along the edge?

(http://img339.imageshack.us/img339/9615/new2lt.jpg)

Hi
As far as I remember, all our VIIC `s had a similar executions as Kaura and the pattern of the "studs" was even all over the steeldeck as shown.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2012, 02:12
Maciek
I cannot remember the average snortingspeed we ended up with, we tried a wide range but the end result was a fairly slow speed, 27 days back and forth to Greenland from westcoast Norway should give an indication.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 03 Feb , 2012, 05:31
(http://Kaura 1953 dummy torpedotest 3.gif)
Tore -
That is a surprisingly smooth (to me) looking torpedo launch from the surface! I would have expected more turbidity and bubbles from a surface shot from tube #1.
At first I thought it was a picture showing that someone cast a mooring line forward and it landed in the water! :-)
Cheers
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2012, 06:18
(http://Kaura 1953 dummy torpedotest 3.gif)
Tore -
That is a surprisingly smooth (to me) looking torpedo launch from the surface! I would have expected more turbidity and bubbles from a surface shot from tube #1.
At first I thought it was a picture showing that someone cast a mooring line forward and it landed in the water! :-)
Cheers
Christopher
Christopher.
This is a dummy torpedo launched rigth outside the submarinepen. It`s a test, the whole idea is to ascertain that no traitorous bubbles escape from the launch. The torpedo is not running thus leaving no trails, but surfacing immediately after the launch. See picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2012, 07:21
Tore, Thanks for the great picture of the bow  :) :)

From other pictures of the Type VIIC/41 bows I have seen, the steel plate along the edge looks smooth (without the small bump - like my drawing below). I was wondering on KNM Kaura was the steel plate in the centre part of the bow, as it the same pattern and type of steel plate found along the edge?

(http://img339.imageshack.us/img339/9615/new2lt.jpg)

Hi
As far as I remember, all our VIIC `s had a similar executions as Kaura and the pattern of the "studs" was even all over the steeldeck as shown.
Tore

Thanks Tore, I will update my drawings.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 03 Feb , 2012, 16:49
and a nice presentation, even a painting behind!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2012, 01:28
and a nice presentation, even a painting behind!
Thanks Rokket, but it`s not so much compare to what I see in this forum. I`m busy  planning and making the displaycase. It`s a challenge to be able to show all the details you put into the model and proper ligths are some of the clues. I`ll use the LED technique and a glasscase without frames and use the weekend to figure out the optimal place for the LEDstrip in the case.
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 04 Feb , 2012, 16:26
Hmmm...I posted about that lovely build yesterday, but it's not here...I also like the presentation with the painting in the bg.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2012, 00:45
Floor covering.
On another thread the question of floorplates and covering came up.I think I a have a wartime picture showing one way of eliminating the floorplate sound. As you can see it looks like pieces of woven mats in the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2012, 03:35
Hmmm...I posted about that lovely build yesterday, but it's not here...I also like the presentation with the painting in the bg.
I`m posting the pencildrawing made by me of KNM Kaura patrolling in northern Norway. The whole " navy"corner includig the glass showcase with LED ligths shall be ready by tomorrow and I`ll post a new picture for you by then if you are interested.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2012, 06:59
While waiting for the showcase to turn up, I`ll post a few pictures of two of my models.
The sub is of course KNM Kaura and the old man of war made of wooden planks is the 66 guns ship The Norwegian Lion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 12:50
KNM Kaura  U 995 Balkongerat/ Gruppenhorchgerat
Some confusion exsist as to if this was installed originally on U 995. It to my opinion it was not and KNM Kaura was not fitted with Gruppenhorchgerat when she was a "frontline" sub in the norwegian navy 1953-1957, She was taken out of service in 1962 and the last years before that she served as a trainingboat.  She was handed over to the germans October 1965 an undated picture of her hanging in the big floatingcranes in Kiel shows her in the Norwegian version with Gruppenhorchgerat (see below). Another picture shows her in the Norwegian version at Laboe on the concretebeds with doors in the pressurehull and Gruppenhorchgerat (see below) and then another picture dated March 13. 1972 she is hanging in the floatingcranes with wintergarten tower and doors cut in the pressurehull without Gruppenhorchgerat. I presume she had for some reason been fitted with Gruppenhorchgerat between 1957 and 1965. Thus she wasn`t equipped with this device originally.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 06 Feb , 2012, 13:05
Tore -
Your model of the Norwegian Lion looks outstanding! Well done Sir! And Your KNM Kaura looks just as proud beside her! Years ago I helped a buddy of mine rig the tallship USS Constitution. She was a board-by-board model, and the rigging was complete. I enjoyed helping on her, and would one day like to build a tallship.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 13:36
Floodgates
Reverting to my last post you migth se another sligtly confusing detail. It is well known that the floodgates are not symetrically arranged on the VIICs. The most significant example is perhaps the utmost forward bowfloodgates. There are two on the stb side and three on the port see (picture below). Revell has not included that in their kits. U 995 (and KNM Kaura) had this standard pattern, however if you look at the early picture from Kiel when she is handed over hanging in the crane in the norwegian version, she all of a sudden got three floodgates on stb side. She has all the time got three stb floodgates at Laboe.
That`s a puzzle.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 13:41
Tore -
Your model of the Norwegian Lion looks outstanding! Well done Sir! And Your KNM Kaura looks just as proud beside her! Years ago I helped a buddy of mine rig the tallship USS Constitution. She was a board-by-board model, and the rigging was complete. I enjoyed helping on her, and would one day like to build a tallship.
Thanks Christopher .
I remember the rigging was a challenge as well. But you made most of the accessories by hand  fi turning the ships bell of brass. We didn`t have PE sets in those days.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 14:12
Well, finally my display case has arrived I have just finished the istallation of the LED ligth and apart from the basplate of mahogany which I shall make later, the model of KNM Kaura is complete . This is my favourite way of displaying models, even my modest model looks OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2012, 17:39
KNM Kaura  U 995 Balkongerat/ Gruppenhorchgerat
Some confusion exsist as to if this was installed originally on U 995. It to my opinion it was not and KNM Kaura was not fitted with Gruppenhorchgerat when she was a "frontline" sub in the norwegian navy 1953-1957, She was taken out of service in 1962 and the last years before that she served as a trainingboat.  She was handed over to the germans October 1965 an undated picture of her hanging in the big floatingcranes in Kiel shows her in the Norwegian version with Gruppenhorchgerat (see below). Another picture shows her in the Norwegian version at Laboe on the concretebeds with doors in the pressurehull and Gruppenhorchgerat (see below) and then another picture dated March 13. 1972 she is hanging in the floatingcranes with wintergarten tower and doors cut in the pressurehull without Gruppenhorchgerat. I presume she had for some reason been fitted with Gruppenhorchgerat between 1957 and 1965. Thus she wasn`t equipped with this device originally.
Tore

Tore, extremely interesting about the Balkongerat on U-995. It has been a very special part of the U-boat for me as U-1308 had one. I been researching this area of the boat for the last three years. There have been numerous things about the Balkongerat on U-995 that I could not make sense of. I have study the other Balkongerat's on the other U-boat and U-995 Balkongerat is the odd one out.

I have study the differences between the changes over to the Type XXI from the Type VIIC/41. By also studying the Type XXI it have help me understand better the Type VIIC/41. A lot of the late war technologies and equipment for the Type VIIC/41 came from the Type XXI research. From this also I have learn a lot about the war late u-boat.
 
I underearth some new information this summer about the Balkongerat which also made no sense to me until today after reading this above. I think I am now starting to understand the Balkongerat on the Type VIIC/41. I can feel the start of a new research article coming soon  ;D
 
Thanks for the information!!!!!!!!  :) :) :) :) :) :) :) :) :)

It made my day!!!!
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2012, 17:48
Tore, I forgot to ask before, were you able to get into a Type XXI, to have a look around?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 23:21
KNM Kaura  U 995 Balkongerat/ Gruppenhorchgerat
Some confusion exsist as to if this was installed originally on U 995. It to my opinion it was not and KNM Kaura was not fitted with Gruppenhorchgerat when she was a "frontline" sub in the norwegian navy 1953-1957, She was taken out of service in 1962 and the last years before that she served as a trainingboat.  She was handed over to the germans October 1965 an undated picture of her hanging in the big floatingcranes in Kiel shows her in the Norwegian version with Gruppenhorchgerat (see below). Another picture shows her in the Norwegian version at Laboe on the concretebeds with doors in the pressurehull and Gruppenhorchgerat (see below) and then another picture dated March 13. 1972 she is hanging in the floatingcranes with wintergarten tower and doors cut in the pressurehull without Gruppenhorchgerat. I presume she had for some reason been fitted with Gruppenhorchgerat between 1957 and 1965. Thus she wasn`t equipped with this device originally.
Tore

Tore, extremely interesting about the Balkongerat on U-995. It has been a very special part of the U-boat for me as U-1308 had one. I been researching this area of the boat for the last three years. There have been numerous things about the Balkongerat on U-995 that I could not make sense of. I have study the other Balkongerat's on the other U-boat and U-995 Balkongerat is the odd one out.

I have study the differences between the changes over to the Type XXI from the Type VIIC/41. By also studying the Type XXI it have help me understand better the Type VIIC/41. A lot of the late war technologies and equipment for the Type VIIC/41 came from the Type XXI research. From this also I have learn a lot about the war late u-boat.
 
I underearth some new information this summer about the Balkongerat which also made no sense to me until today after reading this above. I think I am now starting to understand the Balkongerat on the Type VIIC/41. I can feel the start of a new research article coming soon  ;D
 
Thanks for the information!!!!!!!!  :) :) :) :) :) :) :) :) :)

It made my day!!!!
 
I`m happy you could use the info.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2012, 23:34
XII Gruppenhorchgerat.
We only had VIIC, VIIC/41 and one XIII in our service. I`m only familiar of the two types of VIICs. Sorry I don`t know anything about XXI. I have only seen it in Bremerhaven, Germany.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 06 Feb , 2012, 23:41
yes, love the Lion
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 00:26
NZSnowman
Your interest in XXI is understandable, she is the "mother" of the modern submarines. In the end of the 50s we modernized one of our VIICs KNM Kya  ex U926.
The conningtower was streamlined and became a "sail". Otherwise our VIICs were kept pretty much the same throughout their life as "frontline" subs in the norwegian navy.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 01:33
Tore, the Type XXIII was it the KNM Knerter??? Just wonder were able to get aboard and have a look around?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 01:37
Working and seeing the inside a Type XXI after the Type VII's, must be like driver a model 'T' then going to a ferrari;  Many things similar but everything different  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 02:06
Tore, the Type XXIII was it the KNM Knerter??? Just wonder were able to get aboard and have a look around?
As you know KNM Knerten  ex U4706 was a XXIII type delivered January 1945 and as such a very modern submarine. However she was a coastal sub and as such not very fit for our need. Moreover some parts were removed and we planned to use her for research. However she had a fire  and a small batteryexplosion so she was scrapped and sold in 1953. I was never onboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 04:51
Working and seeing the inside a Type XXI after the Type VII's, must be like driver a model 'T' then going to a ferrari;  Many things similar but everything different  ;D
I believe so, but even then the VIICs as at the end of the war, equipped with snort, were beautiful boats with well proven technique, moreover they were considerable more comfortable acommodationwise than our british built subs. To me, it was a big change beeing educated on british submarines to run a german.The biggest differences between the british and german subs at that time, were apart from the snortmast, the operation of  the vents and valves. The british were hydraulic operated and the germans handoperated by levers and rods.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 09:12
Tore -
I have a question for you about the KNM Kaura - when standing topside on deck, looking down to the torpedo loading hatches, were there bulkheads, perhaps with limber holes, boxing in the hatch and well, or was it open framework? Do you have any pics of that area of the ship?
I found this picture of the White Ensign Models brass PE set, but would like to know if the loading well on Kaura looked like that.
http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg (http://www.whiteensignmodels.com/brochure/images/wembrass/wempe7211.jpg)
Also, was the snort well boxed in as well, or was there just framework supporting the deck around the snort.
Thanks!
Christopher
Christopher
I have been pondering upon your question for a few days and here is my pure guess and migth not be even a clever one as I never have seen the thing. The hatch was sometimes used to take onboard provision even from supplysubs at sea if weather permitted. You would always have some swells causing the sub to roll. From the picture below you see a guy loading a bunch of tincans and indeed there is a sort of casingside forming a box around the hatchopening. If this poor guy would loose one of these tincans it would immediately roll on on the pressurehulls curved surface and disappear in the casing. It would be almost impossible to get hold of at sea. A free rolling tincan in the casing would be the last thing you would have in a sub, the noise would be a killer.
The other picture has a detail while loading a torpedo thru the same hatch. To me it looks like a box that in this case is attached to the hatch and thus stay away from the torpedo loading. This box would`t need to match any frames as it has nothing to do with strengthening. It`s pure guesswork from my side. What do you think?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 07 Feb , 2012, 10:26
Tore-
THAT is exactly the kind of thing I was looking for! And I think your description about what could happen if something got loose in the area between the working deck casing and the pressure hull would be absolutely correct.
I have heard of cases where a tool like a hammer or spanner got loose between the casing during a crash dive. That would be disastrous!
That picture of the torp loading hatch for U-604 has a limbered bulkhead similar to the one for the cook's loading hatch - and could very well be what I need to put around the torp loading hatch on my boat.
I am surprised that there would not be a way for a crewman to get down inside that section of the boat while at sea. There are so many air lines that run over the outer surface of the pressure hull, I would think access to them would be important, but a thin sheet metal bulkhead that would limit "spillage" would make sense.
Thanks for continuing to think about my quandary.
I worked on a few more frames in the forward section, put in my deck stowage box and got my ancher chain and hawser tube in, and am finally laying in the lube lines for the torp gear inside the tauchzelle 5. I will post pics this afternoon.
Thanks again!
Christopher

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 11:59
Moreover some parts were removed ...
Tore

 This is interesting! As currently U-995 has a Type XXIII periscope. Do you guys use the periscope from the Type XXIII before scrapping her?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 12:28
Christopher
Good to hear I have put you on a track. Crawling around in the casing while at sea would be a bit risky. You are trapped in a confined space which even in moderate weather is occasionly submerged without beeing able to move very much. I have been crawling around in the area and as a fairly skinny guy I could manage. I would never send a heavy guy down he could be stuck. But you are rigth, it`s a lot of stuff  there like greaselines which need to be looked after.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 12:50
Moreover some parts were removed ...
Tore

 This is interesting! As currently U-995 has a Type XXIII periscope. Do you guys use the periscope from the Type XXIII before scrapping her?
To my knowledge no. All our VIICs including Kaura (U 995) had a fairly advanced attackperiscope as can be seen on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 14:02
Sorry Tore :-[ I was talking about the sky periscope. The sky periscope in the control room is different from the standard sky periscope for the Type VIIC.
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 14:27
Sorry Tore :-[ I was talking about the sky periscope. The sky periscope in the control room is different from the standard sky periscope for the Type VIIC.
 

Well that scope was a straigth forward scope as you see on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 14:52
Tore, that is correct! The picture of the scope in your post, is of a type used for on the Type VII's. However the currently scope, is of a type used for on the Type XXIII :(

(http://img24.imageshack.us/img24/8648/img1885ls.jpg)
The currently scope on U-995
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2012, 14:57
Christopher
Good to hear I have put you on a track. Crawling around in the casing while at sea would be a bit risky. You are trapped in a confined space which even in moderate weather is occasionly submerged without beeing able to move very much. I have been crawling around in the area and as a fairly skinny guy I could manage. I would never send a heavy guy down he could be stuck. But you are rigth, it`s a lot of stuff  there like greaselines which need to be looked after.
Tore
Tore

By any chance do you have any photographs that you are willing to share of this area between the pressure hull and deck, showing the pipings etc...?

I would found any photographs extremely useful, for my drawing!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 07 Feb , 2012, 15:05
Quote
Tore

By any chance do you have any photographs that you are willing to share of this area between the pressure hull and deck, showing the pipings etc...?

I would found any photographs extremely useful, for my drawing!
I second the motion! :-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2012, 23:44
Quote
Tore

By any chance do you have any photographs that you are willing to share of this area between the pressure hull and deck, showing the pipings etc...?

I would found any photographs extremely useful, for my drawing!
I second the motion! :-)
Sorry I don`t have any drawings. But there are a couple of german books dealing with the german repair and restauration of U 995 where they have removed the casingdeck. These books have photos of the job, but I don`t know if they are of any use to you. I check for the titles of these books.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2012, 00:22
Hi
The pictures in one of the books (I don`t have it and I don`t know the title) are like the the one below. Probably not very useful they have removed a lot of stuff. You can see the forward batteryhatch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2012, 08:43
Christopher.
Further to my post this morning I post another picture of Kaura repairing in Kiel and casingdeck partly removed. You can anyhow cleary see the shape of the outer framing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2012, 01:37
NZSnowman
I rememeber some times ago you launched the idea that all VIIC-VIIC/41s equipped with snortmast having airinlet and exhaust outlet at the hingepivot had a small part of the exhaustpipe protruding through the casingdeck on stb side forward part of the conningtower. I was a little reluctant to that and of the opinion U 995 didn`t have it. My memory failed, I have been scruntinizing all my pictures and finally today I found the evidence that Kaura (U 995) and all our VIICs did have same, see the picture of Kaura below taken in May 1953. I think you can even see the pipebend contains the snortexhaustpipe shut of valve. You are rigth I believe all the VIIC/VIIC-41s having this type of snortmast had pipebend through the casingdeck. Up to this date I have not seen any modelbuilder having got this detail, so back to the workshop, I`ll be the first.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 01:12
A very visible detail on the VIIC and VIIC/41 were the railing which apart from the localisation around the conningtower seems to be ignored by modelbuilders. I think it`s a pitty because it gives a taste of old times submarine to the model. The railing was a standard removeable equipment fitted quite often in harbour and even at sea (see my photo below). However you wouldn`t like to have it fitted on warpatrol as it had a tendency to rattle while submerged. Perhaps this could be an inspiration to give a little different twist to your VIIC model.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Feb , 2012, 01:37
Tore, where were they store onboard?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 01:55
They were very carefully stored in the casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 02:02
Further to my answer perhaps I should mention that the gangway was stowed away in the same area as far as I remember.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Feb , 2012, 02:15
Was storing in the casting something you did only, or did the German's do this also?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Feb , 2012, 04:40
Hi Tore
I believe so, but even then the VIICs as at the end of the war, equipped with snort, were beautiful boats with well proven technique, moreover they were considerable more comfortable acommodationwise than our british built subs. To me, it was a big change beeing educated on british submarines to run a german.
It is really surprising opinion - there is commonly said, that crew habitability on german boats was extreme rough in comparison to the allied (us and uk) subs.
 
The biggest differences between the british and german subs at that time, were apart from the snortmast, the operation of  the vents and valves. The british were hydraulic operated and the germans handoperated by levers and rods.
As far as I know, the larger boats (types IX, XB XIV and XXI) had vent valves operated by means of compressed air pistons/actuators (with emergency hand drive of course).


I have question - comparing the photos from control room of U-995 and U-570 I see, that the first one has bow (and aft) bouyancy tanks (Wasserdichte Heck/Back) vent valves opened from the control room (by means of the rods and hand wheel - similar to the main ballast tanks 1 and 5 vent valves), while on U-570 these valves are opened from the aft and forward torpedo room respectively.


Was this "remote" drive introduced by Germans or by Norwegians?


(http://uboatarchive.net/U-570Photo17.jpg)
(http://uboatarchive.net/U-570Photo17.htm (http://uboatarchive.net/U-570Photo17.htm))


(http://www.submarineresearch.com/images/U-995-control.jpg)
(http://www.submarineresearch.com/bull58.html (http://www.submarineresearch.com/bull58.html))
--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 04:41
I believe the germans did it as well. Apart from the pressure containers with spare torpedoes and the rubberdingies containers,which sometimes were used for potatoes. Different  stuff was stowed away in the casing but everything had of course to be properly secured and could be a hazard when subject to depthcharging.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Feb , 2012, 04:43
Hi Simon
Was storing in the casting something you did only, or did the German's do this also?
I have seen descriptions, that "seem
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 04:56
Maciek
Im not familar to the other german types of submarines but I`m not surprised they were equipped with hydraulic or pneumatic valves. Handoperated valves by rods and levers were to a certain extent requiring a lot of maintenance.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 05:16
Accomodationstandard. German versus British subs.
I would challenge the statement that the german subs.(VIICs) had a crude crewhabitability compared to british. May be it could be true using the A class and to a certain extent T class as a counterpart, but for sure not the V (U) class. In fact most of our recruits put the VIIC up as alternative 1 when applying for boat.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Feb , 2012, 05:26
According to the upperdeck stowage, I'm attaching the part of the
"Tauchvorschrift f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 05:36
Remote operated vents.
They were german originally to my knowledge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 05:56
According to the upperdeck stowage, I'm attaching the part of the
"Tauchvorschrift f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Feb , 2012, 09:22
Hi Tore


You have some very interesting documents. The german instructions you are showing is almost the same as we used. Do you happen to have any german descriptions or schematic drawings of the snort system not having the pipeconnections up at the tower  (as you previosly showed), but at hollow snortpivotshaft?


No, I don't have anything describing this variant of schnorchel installation. The best what I have seen is the document developed by Simon.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Feb , 2012, 12:20
Maciek, and Tore

My article about the schnorchel should be going up this weekend on the AMP site, it have my latest drawing on the schnorchel  :) Also should have good size update for my "Drawing Drawing' within the next week or so. Just need to check a few things first.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2012, 12:41
Maciek, and Tore

My article about the schnorchel should be going up this weekend on the AMP site, it have my latest drawing on the schnorchel  :) Also should have good size update for my "Drawing Drawing' within the next week or so. Just need to check a few things first.
Excellent! Looking forward to seeing it. I just finished the famous snort exhaustpipebend on top of the casingdeck and shall install it tomorrow as soon as the paint is dry.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Feb , 2012, 19:06
Tore, here could be a good test for you memory. Below are pictures of the bulkhead between the CR & mass. On the right of the picture, we can see a pipe with a colour code (purple with red band). One of my document I have say it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Feb , 2012, 06:09
Tore, here could be a good test for you memory. Below are pictures of the bulkhead between the CR & mass. On the right of the picture, we can see a pipe with a colour code (purple with red band). One of my document I have say it’s a Fuel oil transfer lines. Do you know if this is correct?

(http://img72.imageshack.us/img72/3641/new1yd.jpg)

(http://img196.imageshack.us/img196/4239/new2yb.jpg)

Hi
I can`t remember this particular pipebend neither the colourcode. To my opinion this could very well be the fueltransferpipe from the no 1 stb regulating/fuelstoragetank ( in the saddle) which goes into the CR where it connects via valves to other saddlefuelstorage tanks and then to the engineroom via common pipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Feb , 2012, 12:53
Tore, from what you saw on KNM Kaura and your understanding of German U-boat design what do you think the German
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 00:31
NZSnowman
I presume you are referring to the relevant fuel transferpipe. Most of the VIIC saddle tanks were used as storage for fuel and not as common ballasttanks.Even the saddleregulatingtanks could be used for fuelstorage to increase the operating range. If this pipe is identified correctly as fueltransferpipe, my suggestion is the pipe leads from the no 1 stb. regulatingtank in the saddle outside the PO mess to the common fuelsupplypipe in the CR. and is normally shut and only used in those cases you carry fuel in the regulatingtank no. 1stb. I hope I understood your question correct, otherwise please revert.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 00:52
Tore, from what you saw on KNM Kaura and your understanding of German U-boat design what do you think the German
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 02:36
NZSnowman
I rememeber some times ago you launched the idea that all VIIC-VIIC/41s equipped with snortmast having airinlet and exhaust outlet at the hingepivot had a small part of the exhaustpipe protruding through the casingdeck on stb side forward part of the conningtower. I was a little reluctant to that and of the opinion U 995 didn`t have it. My memory failed, I have been scruntinizing all my pictures and finally today I found the evidence that Kaura (U 995) and all our VIICs did have same, see the picture of Kaura below taken in May 1953. I think you can even see the pipebend contains the snortexhaustpipe shut of valve. You are rigth I believe all the VIIC/VIIC-41s having this type of snortmast had pipebend through the casingdeck. Up to this date I have not seen any modelbuilder having got this detail, so back to the workshop, I`ll be the first.
Tore
As a consequence of  NZSnowmans researchs and the above I went back to the drawingboard and installed the pipe on my Kaura ( ex U 995) model as can be seen on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Feb , 2012, 12:37
Tore, can you remember if the high pressure Oxygen bottle behind the rear engine housing and clutch were painted or unpainted? And if painted that colour they were?
 
Were some suggestion that the German
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 13:26
I believe they were painted dark grey and they could very well have a dark blue top I am not 100% sure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 Feb , 2012, 16:03
Hi Tore, Simon

Tore, here could be a good test for you memory. Below are pictures of the bulkhead between the CR & mass. On the right of the picture, we can see a pipe with a colour code (purple with red band). One of my document I have say it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 23:17
Hi Tore, Simon

Tore, here could be a good test for you memory. Below are pictures of the bulkhead between the CR & mass. On the right of the picture, we can see a pipe with a colour code (purple with red band). One of my document I have say it’s a Fuel oil transfer lines. Do you know if this is correct?

(http://img72.imageshack.us/img72/3641/new1yd.jpg)

(http://img196.imageshack.us/img196/4239/new2yb.jpg)
I think, you both are partially right. I think, that this is sounding/test/vent line for the inboard fuel oil tank 1.
Here is the control room side of the above bulkhead:
(http://www.freeimagehosting.net/newuploads/wao96.jpg)
On this diagram I have marked corrensponding parts of installation:
(http://www.freeimagehosting.net/newuploads/95rk2.jpg)
(http://uboatarchive.net/U-570Plate8A.htm)
Compare the hull valve handle with the one on this diagram (treibol bordv):
(http://www.freeimagehosting.net/newuploads/o8mh1.jpg)
(http://uboatarchive.net/U-570Plate1.htm)
Using this panorama you can see the drain line and the "bucket" for the fuel oil.
http://www.kubische-panoramen.de/index.php?id_id=5378


--
Regards
Maciek
Hi Maciek
I think you are absolutely rigth. The high quality photo from the CR bulkhead and the diagram and valvediagram is quite clear.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2012, 23:32
Tore, can you remember if the high pressure Oxygen bottle behind the rear engine housing and clutch were painted or unpainted? And if painted that colour they were?
 
Were some suggestion that the German’s painted the top of them dark blue  ???
 
Thanks, Simon.
Simon
Coming back to your above question. If you are making a drawing of this area, I would like to mention an important detail. Between the engines and the pressurehull quite a bit of spareparts were fixed to the bulkhead. In this particular area I believe a spare piston was mounted in a round gray container of app. 450-500 mm diameter and 6-700 mm deep. The container was filled with conservation oil and was quite domenating.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Feb , 2012, 03:48
Hi


Coming back to the Schnorchel - Tore, do you remember, if following wheel in the forward control room
is the drive for the Schnorchel locking shaft?
Simon, have you done any research related to this part?
(http://www.freeimagehosting.net/newuploads/a9873.jpg)
(http://www.freeimagehosting.net/newuploads/vkbmx.jpg)


http://www.deutschland-panorama.de/museen/laboe_technisches_museum/ps/10_1051_04.php
--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Feb , 2012, 07:21
 Tore


One more question - for a long time I'm wondering what this thing is:


(http://www.freeimagehosting.net/newuploads/uevvd.jpg)


It is located in the stb, forward part of the bow torpedo room. It is connected with two pipes with two valves above the torpedo tubes:

(http://www.freeimagehosting.net/newuploads/q4ynf.jpg)


The similar arrangement is in the diesel engines room (near the bulkhead between diesel engines and electric motor rooms):
(http://www.freeimagehosting.net/newuploads/euzpo.jpg)
(http://www.freeimagehosting.net/newuploads/5z8di.jpg)


My best guess: it is some kind of hand pump for pumping the lubricating oil to the grease lines of mechanical gears outside pressure hull, but I cannot confirm it in any way.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 07:39
Hi


Coming back to the Schnorchel - Tore, do you remember, if following wheel in the forward control room
is the drive for the Schnorchel locking shaft?
Simon, have you done any research related to this part?
(http://www.freeimagehosting.net/newuploads/a9873.jpg)
(http://www.freeimagehosting.net/newuploads/vkbmx.jpg)


http://www.deutschland-panorama.de/museen/laboe_technisches_museum/ps/10_1051_04.php (http://www.deutschland-panorama.de/museen/laboe_technisches_museum/ps/10_1051_04.php)
--
Thanks, regards
Maciek
Maciek!
Yes I think it is.However your picture of the lockingpin external on what I presume is the Laboe U 995 is not the way it was. The rod for the wheel was fitted in an external tube outside the conningtower as I hope you can see on my bad quality picture below. This is the way it was fitted on the U 995. I have seen 3 executions of the transmissionrods to the wheel, external all the way to the deck and then into the conningtower, the way shown on your picture and the original way on KNM Kaura  (U 995).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 08:06
Maciek
You are rigth, these devices were for greasepumping to the mechanical links partly outside (in the casing) the pressurehull. As far as I remember a few pipes led  from the pump via shut off valves in the pressurehull to distribution boxes for greasepoints outside . May be something for Christophers forward greaselines project?
We had a special man ,a "greaser", who was responsible for these points.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 08:11
Maciek.
Having had another look at your Laboe U 995 picture I see they have removed the snortlockingrod completely so it doesn`t show an alternative. Why did they do that?
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Feb , 2012, 09:07
Hi Tore



Yes I think it is.However your picture of the lockingpin external on what I presume is the Laboe U 995 is not the way it was. The rod for the wheel was fitted in an external tube outside the conningtower as I hope you can see on my bad quality picture below. This is the way it was fitted on the U 995. I have seen 3 executions of the transmissionrods to the wheel, external all the way to the deck and then into the conningtower, the way shown on your picture and the original way on KNM Kaura  (U 995).

Yes, I also have seen the implementation of this rod similar to this one:
(http://www.freeimagehosting.net/newuploads/ze8wj.jpg)
(U-1009 in Lisahally)



Having had another look at your Laboe U 995 picture I see they have removed the snortlockingrod completely so it doesn`t show an alternative. Why did they do that?
Well, that's a good question. I have another - on U-995 in Laboe is not visible the exhaust pipe branching forward the exhaust gas blowing valve box (connning tower stb) and going forward, over the deck, to the schnorchel mast.
(http://www.freeimagehosting.net/newuploads/lfzxk.jpg)


(http://www.freeimagehosting.net/newuploads/tuiv8.jpg)
(U-249 in Eriboll)


Was it like this before?


You are rigth, these devices were for greasepumping to the mechanical links partly outside (in the casing) the pressurehull. As far as I remember a few pipes led  from the pump via shut off valves in the pressurehull to distribution boxes for greasepoints outside . May be something for Christophers forward greaselines project?
We had a special man ,a "greaser", who was responsible for these points.

Great! Thank you for confirmation.


--
Thanks, regards

Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 10:53
On the Laboe U 995 they have changed several things in this area. As you have noticed exhaustbend on deck stb fwd conningtower is removed,(see picture of the original below) snortmast lockingpin rod removed, original compasshousing changed with a newer version ( see original version below) and the snortmast topheadvalve exchanged with a hingefloat. E.g old constructions exchanged to new contructions,and some new constructions changed back to old. I don`t get it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 10:59
Maciek
U 249 locking pin snort. Yes this how the original U 995 looked like.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Feb , 2012, 12:40
Schnorchel

Yes, that right the 'black' painted handle is to control the control arm for locking/unlocking the pin within Schnorchel restraining bracket. There are two known styles for the control arm:

STYLE 1
The control arm runs through the spray deflector then along the outside of the conning tower unshielded to the deck.

STYLE 2
The control arm runs through the spray deflector then is shielded by a larger half round diameter pipe to the deck.

The
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 13:14
Yes Simon, you are rigth.I just had a flash look at the Laboe U 995 and got the impression the germans had displayed a 3. alt. by taking the lockingpin rod into the conningtower just above the spraydeflector.At a second look I realised they just simply have removed the whole thing and just let the connectingend of the pin hanging free in the air, unbelievable.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 14 Feb , 2012, 14:54
Quote
You are rigth, these devices were for greasepumping to the mechanical links partly outside (in the casing) the pressurehull. As far as I remember a few pipes led  from the pump via shut off valves in the pressurehull to distribution boxes for greasepoints outside . May be something for Christophers forward greaselines project?
We had a special man ,a "greaser", who was responsible for these points.

:-) Interesting! I always thought that was the coffee-maker for The Lords!! ;-) Now I have to dig up some info on these distribution boxes.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2012, 23:33
Quote
You are rigth, these devices were for greasepumping to the mechanical links partly outside (in the casing) the pressurehull. As far as I remember a few pipes led  from the pump via shut off valves in the pressurehull to distribution boxes for greasepoints outside . May be something for Christophers forward greaselines project?
We had a special man ,a "greaser", who was responsible for these points.

:-) Interesting! I always thought that was the coffee-maker for The Lords!! ;-) Now I have to dig up some info on these distribution boxes.
Christopher. Coffee-maker! You should know better, the coffee was made almost in the crews lavatory and the coffeetaste would match any fancy taste made today!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Feb , 2012, 01:47
Hi Tore


original compasshousing changed with a newer version


That's interesting - I have always thought that U-995 (and KNM Kaura later) was equiped with this newer version compass housing (specific for the late versions of the type VIIC/41):
(http://img151.imageshack.us/img151/7305/u1023rddition.jpg)

(http://img525.imageshack.us/img525/6778/u1023.jpg)
 (U-1023)
(http://img529.imageshack.us/img529/9283/u1305.jpg)
(U-1305)


It is significantly smaller than housing in the earlier versions of the type VIIC. I guess, it is because in the late VIIC/41 some parts of the salvage/emergency blowing installations which were also in this housing were removed.


I have been also wondering, how the magnetic compass (and the light transmission system to the control room) looked like.


Tore, one more question - I know, that apart from the depth gauges in the control room, there were two gauges in the forward and aft torpedo room each. On U-995 in Laboe I have never seen these. Do you remember, where they were located?


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Feb , 2012, 02:32
Hi Tore


original compasshousing changed with a newer version


That's interesting - I have always thought that U-995 (and KNM Kaura later) was equiped with this newer version compass housing (specific for the late versions of the type VIIC/41):
(http://img151.imageshack.us/img151/7305/u1023rddition.jpg)

(http://img525.imageshack.us/img525/6778/u1023.jpg)
 (U-1023)
(http://img529.imageshack.us/img529/9283/u1305.jpg)
(U-1305)


It is significantly smaller than housing in the earlier versions of the type VIIC. I guess, it is because in the late VIIC/41 some parts of the salvage/emergency blowing installations which were also in this housing were removed.


I have been also wondering, how the magnetic compass (and the light transmission system to the control room) looked like.


Tore, one more question - I know, that apart from the depth gauges in the control room, there were two gauges in the forward and aft torpedo room each. On U-995 in Laboe I have never seen these. Do you remember, where they were located?


--
Thanks, regards
Maciek


Maciek & Tore, here is a list I started on the changes for U-995 a few years back. It is in way finish!

Upper Wintergarten Platform

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2012, 04:53
Maciek
KNM Kaura VIIC/41 (U-995) had the old compass version. KNM Kya ( U926) and KNM Kinn (U1202) both VIIC had the new version.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2012, 05:03
Maciek
Depth gauges.
You are rigth there were depthgauges, but I cannot rembember excatly were they were located. I think one was located to the port side in the engineroom next to the manoeuvering place fwd engines, but I am not sure. It was important to know the depth particulary while snorting.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2012, 05:34
Simon.
On KNM Kaura (U995), KNM Kya (U926) and KNM Kinn (U1202) they removed the wintergarten completely before they were put into norwegian service 1951-1952 and made a new different one as can be seen below. The structure was completely welded, no hatches or doors, the railing protruding about 30 cm out from the topfloor widening the circumference of the floor by having 3 floorbars. The structure tapered considerably down to the casingdeck as can be seen on the photo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2012, 06:18
Simon
Your list on changes of U995 further to my post on wintergarten.
We didn`t have the balkongerat originally, it must have been introduced sometime after 1959. We had only two pressure containers for storage on casingdeck, not 4 , KNM Kya (U 926) had 3 and KNM Kinn (U 1202) had 4. KNM Kaura ( U 995)  had as known the snortmast lockingpin in a case outside the conningtower on KNM Kya (U 926) inside the conningtower below the spraydeflector and on KNM Kinn (U 1202) the same I believe. Otherwise I agree to your list.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2012, 08:44
Simon
Snortmast lockingpin.
You are mentioning 2 versions:        1. Through  spraydeflector and along outside the conningtower to the deck.
                                                          2.  Through spraydeflector and then shielded by a half round pipe to deck KNM Kaura (U995) version.
There is indeed a 3rd version, through the spraydeflector and then inside the conningtowercasing to the deck. The KNM Kya ( U926) and Kinn (U 1202) had both this version. See picture below of KNM Kya.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Feb , 2012, 12:32
Simon
Snortmast lockingpin.
You are mentioning 2 versions:        1. Through  spraydeflector and along outside the conningtower to the deck.
                                                          2.  Through spraydeflector and then shielded by a half round pipe to deck KNM Kaura (U995) version.
There is indeed a 3rd version, through the spraydeflector and then inside the conningtowercasing to the deck. The KNM Kya ( U926) and Kinn (U 1202) had both this version. See picture below of KNM Kya.
Tore

Cool! Thank you! I have not seen that style before. I will update my article.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2012, 00:27
KNM Kaura (U 995) Upper wintergarten modification. Further to my post on feb.15th. You list of changes done to U 995. I don`t remember any ammunitioncontainer on the norwegian version of the wintergarten. We never had any guns there. As I said it was a completly new construction.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2012, 06:12
Simon
Snortmast lockingpin.
Just a correction to my previous post. U 1202 KNM Kinn did not have alt. 4 but alt. 2.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Feb , 2012, 14:13
Tore, do you have any close-up or clear pictures of the wooden deck? I am trying to workout the size of the wooden boards and the spacings.

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2012, 15:12
Tore, do you have any close-up or clear pictures of the wooden deck? I am trying to workout the size of the wooden boards and the spacings.

Thanks, Simon.
Simon
The only photo I have would be the below. The references could be the forward pressurecontainer which is placed at the same frame as the original or may be the original hatch in the foreground.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2012, 05:00
Simon
The below picture migth give you some more info.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2012, 05:15
Simon
As a follow up on my two pictures. Many modellers have shown great innovation in the colours of the wooden deck, although it was made of pine it had a fairly even dark grey almost black colour and you couldn`t see any shiny filister heads neither any salty deposit or barnacles even after 27 days submerged. To all those weatheringenthusiasts, if you want to give a correct impression of a VIIC behave at least to the colour of the wooden deck.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Feb , 2012, 11:49
 Thank, Tore! Both pictures were very useful. I also look at other pictures of the Type VIIC's late-war deck style. And I found something common with then...they are all different  ;D
 

Below this the colour I have gone for. It
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Feb , 2012, 11:55
 Tore, can you remember how the wooden deck was fix? Could you see the metal bolts or were there small wooden plugs reset within the bolt holes? 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2012, 13:24
Thank, Tore! Both pictures were very useful. I also look at other pictures of the Type VIIC's late-war deck style. And I found something common with then...they are all different  ;D
 
  • The widths of the wooden boards are many.
  • The spacing between the wooden boards is much the same.
  • The workmanship with the decking also was very variable, some were very nice and very good, while others looked like it was build in a rush.

Below this the colour I have gone for. It’s a little lighter now, but it will darken after I get it printed.
 
(http://img836.imageshack.us/img836/8114/typevii4132b.jpg)
Simon
I think you should  skip the yellowish tint. It was very dark almost black gray (like cinders if you know that kind of coke) and you didn`t see the woodgrainpattern.
The the wooden deck of U 995 at Laboe  has a terrible quality, warped and uneven it was definitely not like that, however the colour is not far from what it used to be.
Tore
tore
 Tore, can you remember how the wooden deck was fix? Could you see the metal bolts or were there small wooden plugs reset within the bolt holes? 
Simon I believe they were galvanized
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2012, 13:38
Simon
Fixing of wooden deckboards . I believe they were bolted with galvanized bolts having filisterheadsupwards approximately same colours as the deck. I cannot remember any wooden pegs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2012, 14:07
Simon.
I see you have left the conningtower hatch without any details,sure it will come. Don`t forget the catch keeping the hatch open.
The conningtowerhatch was very important as it was vital that the CO got on the top as quick as possible. The problem was that after having been submerged over a long periode the could be a substantial overpressure in the sub due to smaller leakages and fi using the airdriven exhaustvalvegrinder. Equalizing the pressuredifferance could take time and was often skipped as a routine we had always a man with a firm grip around the CO`s legs when he opened the hatch which flung open. I never saw it but was told that CO `s have been jettisoned out of the hatch. I noticed howewer that the air inside turned into fog by the sudden pressuredrop.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Feb , 2012, 12:40
Simon.
I see you have left the conningtower hatch without any details,sure it will come. Don`t forget the catch keeping the hatch open.
The conningtowerhatch was very important as it was vital that the CO got on the top as quick as possible. The problem was that after having been submerged over a long periode the could be a substantial overpressure in the sub due to smaller leakages and fi using the airdriven exhaustvalvegrinder. Equalizing the pressuredifferance could take time and was often skipped as a routine we had always a man with a firm grip around the CO`s legs when he opened the hatch which flung open. I never saw it but was told that CO `s have been jettisoned out of the hatch. I noticed howewer that the air inside turned into fog by the sudden pressuredrop.
Tore

Very interesting, about the pressure different! I did note the hatch fastening. I decided to leave the hatch out at this stay as I was not happy with my original drawing. I want to redraw it.

Simon
Fixing of wooden deckboards . I believe they were bolted with galvanized bolts having filisterheadsupwards approximately same colours as the deck. I cannot remember any wooden pegs.
Tore

Thanks for the information  :)

Simon
The only photo I have would be the below. The references could be the forward pressurecontainer which is placed at the same frame as the original or may be the original hatch in the foreground.
Tore

Thanks for the pictures  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Feb , 2012, 00:58
Maciek
As a remark to my statement a few days ago concerning comparison of habitability standard between british and german submarines, I shall elaborate that a little more. You have of course rigth that the litterature is full of statement that the allied subs were better. VIICs were comparatively smaller than the US and british subs .I dont`know the US types so well but I sailed the british A,T and S class they were fairly comfortable, the A had even a "captains quarter" in a separate pressurehull adjacent to the conningtower. We had only U class of british make subs and if you compare the accommodation of those to a VIIC the latter was a winner. Both classes had about the same crewmembers but the U class was smaller inside and hence the accomodation was more cramped. The main reason for that is  it didn`t have saddletanks. The VIICs saddletanks made it also more comfortable in heavy sea (less rolling).  We had late nigths discussions about  of the design of the two types and I`m not sure if we had a clear winner, but apart from the accommodation question I think amongst the engineers the german diesels were the winners.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Feb , 2012, 06:25
Simon
Further to my post on the colour of the deck I found an interresting instruction from the German navy high command. You probably know the Submariners handbook no 1643 revised version of 1943, today published on the net by HNSA Historic Naval Ships Associaton. Section I
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 22 Feb , 2012, 11:56

Tore,
On page 104 and 105 of the Manual at http://uboatarchive.net/Manual.htm (http://uboatarchive.net/Manual.htm) it is stated that:
"... To support bulkheads and seal leakages, the following materials are provided on the boat: Leak shoring material. 4 Leak shoring timbers each 200 x 10 x 10 cm and 4 boards @ 75 x 30 x 4 cm are carried in the forward torpedo room"
Did the Norwegian Navy use the same equipment for leak sealing, or did they have different, post-war improvements?
Do you know where these were stored - Did they form the "walking deck" over the torpedos or were they extra gear carried in excess of the normal false flooring?
There is mention of other boards and planks for leak sealing in the diesel engine rooms and aft torpedo rooms. Do you know where these were stored as well?


Thanks for all of your input!  ;D
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2012, 13:04

Tore,
On page 104 and 105 of the Manual at http://uboatarchive.net/Manual.htm (http://uboatarchive.net/Manual.htm) it is stated that:
"... To support bulkheads and seal leakages, the following materials are provided on the boat: Leak shoring material. 4 Leak shoring timbers each 200 x 10 x 10 cm and 4 boards @ 75 x 30 x 4 cm are carried in the forward torpedo room"
Did the Norwegian Navy use the same equipment for leak sealing, or did they have different, post-war improvements?
Do you know where these were stored - Did they form the "walking deck" over the torpedos or were they extra gear carried in excess of the normal false flooring?
There is mention of other boards and planks for leak sealing in the diesel engine rooms and aft torpedo rooms. Do you know where these were stored as well?


Thanks for all of your input!  ;D
Christopher
Christopher
I cannot remember we carried any timber whatsoever. Occasionally we used some as help during maintenance work. But the  timber was left ashore. I doubt if the timber would be of any help for possible dammage while submerged. The pressure would too high in most cases. We had no other devices for major structure damagecontrol. I don`t know where the germans would possibly store the timber, sorry.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 22 Feb , 2012, 13:31
Quote
...I don`t know where the germans would possibly store the timber, sorry....
Good to know! I will see if I can figure out where such timber was kept if it was actually carried at all, but will not worry too much over it. After all, the drawings show that type VII's had small boats stored under the top deck but it is known that they did not all carry them as planned.
Thanks again!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Feb , 2012, 02:59
Tore
I have got a question - do you remember what this box is?
(http://www.freeimagehosting.net/newuploads/fiz3h.jpg)
It is located in the aft, port corner of the forward torpedo room, and is labeled "AGOS".
I have no idea, what is this for, I suspect, it is not german, but introduced later, by Norwegians.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2012, 05:02
Maciek
I cannot remember ever to have seen this box, so I presume it has been installed after my time onboard. It looks like an US made box to me and that migth give a clue. AGOS  was (is?) a name for US Ocean Surveillance Ships gathering acoustic datas in support of the Navys antisubmarine warfare branch. My guess is the box has something to do with equipment linked up to that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 23 Feb , 2012, 08:51
Quote
... I cannot remember ever to have seen this box, so I presume it has been installed after my time onboard.
It will be challenging to try to figure out what subtle changes were made from when the Germans had the boat in the first place, to when you were there and the Norwegians added and modified it, and the years after.
I am glad we have a primary source such as your self! Thanks!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2012, 10:13
Christopher
I guess you endeavour to make your model as close as possible to the original of the VIIC at a specific time. Changes seems to have been a continious process on the type. When we took over the U 995, she was still at the yard in Norway for retrofit and the Germans never sailed her as she was after that. All our 3 VIIC were different and you noticed it at once coming onboard. After KNM Kaura (U 995) had her retrofit at the yard she was a "frontline" sub. in our navy and in the last years a training sub til 1962. I have the impression she was used for different experiments in the last years and that`s probably when she got changes like the balkongerat and other stuff. When the Germans got her back, they made considerable changes again and used sometimes easy and even uncorrect changes (repairs).It is not easy to figure out what is original or phantasy on the Laboe  U995. In addition it seems they have given everybody a paintbrush so the could paint to they hearts desire camouflaging the details thoroughly in vivid colours. You have indeed a challenging task ahead of you in making you details and I wish you every success in your task. Allthough modest, I`m happy to be able to give a little help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Feb , 2012, 11:12
Maciek
I cannot remember ever to have seen this box, so I presume it has been installed after my time onboard. It looks like an US made box to me and that migth give a clue. AGOS  was (is?) a name for US Ocean Surveillance Ships gathering acoustic datas in support of the Navys antisubmarine warfare branch. My guess is the box has something to do with equipment linked up to that.
Tore

I have a feeling that the balkongeratand and this box were install at the same time  ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2012, 11:24
Simon
I believe you have a point and as an extra info even one of our VIICs, KNM Kya ( U 926) was converted with a sail conningtower after my time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Feb , 2012, 02:19
Hi Tore
I cannot remember ever to have seen this box, so I presume it has been installed after my time onboard. It looks like an US made box to me and that migth give a clue. AGOS  was (is?) a name for US Ocean Surveillance Ships gathering acoustic datas in support of the Navys antisubmarine warfare branch. My guess is the box has something to do with equipment linked up to that.


Thank you for answer.
--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2012, 07:34
Christopher.
You mentioned earlier you was a PADI Divemaster. I`m not going to start a new thread on that but this migth have some common submarine interest. As a part in our submarine engineerining training I got my first certificate as a shallow water diver in 1953 quite a bit before the scubadiving was common. The equipment was based on the submarine escape eqipment called the Davies apparatus using oxygen but modified for diving. The idea was that the engineering officer should be able to inspect and even make sketches of damages to  hulls or objects below the surface. As can be seen on the pictures below, we didn`t use flippers but boots with lead soles. Well at the bottom (6-8 meters) they lowered various items  which you should inspect and write or sketch  on a board. At the end came a sign : "do you like gin?"when you wrote "yes" on the board, you could surface and get your certificate. As you see on the pictures we used a rubber drysuit which pinched terribly. Sorry this post was a bit outside the VIIC topics
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 25 Feb , 2012, 15:41
This is Your thread, so now worries on topic. if it gets too wild we'll split. The system is meant to serve us, and not the other way around! Cool stuff by the way! It might be interesting to compare this setup with the US escape gear (Momsen Lung) and any others. I look at "parallel invention". My own personal survey of electrical plugs and sockets of modern times: USA = small and wimpy, with bad wire nut connections in junction boxes; UK = huge and chunky plugs, don't know about wiring; Australia = compact yet substantial, with really simple and secure screw connection inside boxes and switches. USA has good junction boxes, yet half the power of Aus, Aus has crappy exposed (internally) switch boxes. All do the same thing, and for practical purposes, equally well, but all are different!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2012, 23:37
This is Your thread, so now worries on topic. if it gets too wild we'll split. The system is meant to serve us, and not the other way around! Cool stuff by the way! It might be interesting to compare this setup with the US escape gear (Momsen Lung) and any others. I look at "parallel invention". My own personal survey of electrical plugs and sockets of modern times: USA = small and wimpy, with bad wire nut connections in junction boxes; UK = huge and chunky plugs, don't know about wiring; Australia = compact yet substantial, with really simple and secure screw connection inside boxes and switches. USA has good junction boxes, yet half the power of Aus, Aus has crappy exposed (internally) switch boxes. All do the same thing, and for practical purposes, equally well, but all are different!
Rokket
Indeed quite similar to Momsen lung. The thing was they didn`t have the regulators at that time so they used the "bag" to adjust the ambient breathing pressure, inside the bag was  a cannister with barium hydrooxide absorbing the CO2.
You are rigth about the UK boxes they were huge and the design required a consumption of gunmetal which the germans even couldn`t dream about. The differences are  like fingerprints which make it possible to indentify various items in a hotchpotch like U 995 and that makes the research interesting. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 27 Feb , 2012, 00:24
You are optimistic when you call the challenge of 995 "interesting"! I'd use frustrating! Oh for a time machine...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Feb , 2012, 01:38
Hi Tore
Maciek & Tore, here is a list I started on the changes for U-995 a few years back. It is in way finish!
 
Bow Torpedo
  • High Pressure Air bank № 4 missing.
  • Torpedo Tube - Original torpedo tube № III replace, probable exchange by the Norwegian Navy launch some 533mm post war torpedoes.


(http://u-995.com/images/galerie/bugraum/bugraum13.jpg)
Forward, bottom, stb torpedo tube.


(http://u-995.com/images/galerie/ht01.jpg)
Aft torpedo tube (original).


Do you remember details of the modifiacion of forward torpedo tube? It seems, that the tube as well as
whole external fittings and armature is orignal (or restored), but the interior of the tube is quite new. For
me it seems, like the tube was drilled out - the width of the tube walls was decreased and lined with four
guidnesses.


Some time ago I have tried to describe the german uboat's torpedo tubes and I'm still interested in all
details related with this topic.
http://www.ubootwaffe.pl/component/option,com_flexicontent/Itemid,76/cid,66/id,337/view,items


--
Thanks, regards
Maciek



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2012, 05:19
Maciek
What an impressive document you published. No, I cannot remember we did anything to the torpedotubes in my time, so I presume it migth have been done afterwards. Allthough torpedoes and tubes were not at all my job it was left to the torpedopeople onboard, I followed with interest their discussion on the german torpedoes which basicly dealt with the LUT torpedoes and I doubt if we ever had an other make but german in my time. We spent a lot of time and effort on the LUT. I presume you have seen my photo of a dummy torpedo surface shot just to check the ejection, otherwise see below
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 Feb , 2012, 17:55
Tore
Once again, thank you for your answers. I have got another question - I'm wondering what was your practice to measure the CO2
concentration during longer submerged cruises?
From the reports, I know, the Germans used something called "air sampling tubes, a Drager-measuring apparatus, or an Orsat testing setup".
Was your approach different? Or did you use something similar? If so, could you explain how it worked?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 29 Feb , 2012, 18:25
Tore!
I LOVE your story about your initial scuba training! The pics of the early "submerged - engineering - inspection - apparatus" as I would have called it, was outstanding!
Some day I shall have to relate the story of a young trainee who invented the underwater yo-yo! :-)
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2012, 00:14
Tore
Once again, thank you for your answers. I have got another question - I'm wondering what was your practice to measure the CO2
concentration during longer submerged cruises?
From the reports, I know, the Germans used something called "air sampling tubes, a Drager-measuring apparatus, or an Orsat testing setup".
Was your approach different? Or did you use something similar? If so, could you explain how it worked?


--
Thanks, regards
Maciek
Well Maciek I guess you have to realize this was back in the early fifthies and we did`t have very sofisticated outfit for oxygen and CO2 mesurements except for a box  from the germans with some chemicals which we tried once. I don`t remember what kind of chemicals but it was a fairly simple step to step instructions what to do.
We did`t make any science about it and used our experience and how the body reacted, primarely panting for the excessive CO2 and for oxygen, well honestly we allowed a cigarette per man occasionally (very seldom), if the match wouldn`t ligth we were low on oxygen.
I know most submarines were equipped with testkit, but I doubt if it was regulary used. An experienced submariner can feel a lot on his body about the quality of the air in additon to the time you have been submerged and the activity of the crew.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2012, 00:38
Tore!
I LOVE your story about your initial scuba training! The pics of the early "submerged - engineering - inspection - apparatus" as I would have called it, was outstanding!
Some day I shall have to relate the story of a young trainee who invented the underwater yo-yo! :-)
Christopher
It`s easy to forget the enormous development which has taken place on diving and submarines the past 60 years. 60 years ago,in my time, escape excercises from sunken submarines were not common, but after a few disasters  prior to my submarinetraining (HMS Truculent and HMS Affray) the newspapers started to scream and in UK where I was trained, came eventually an 100`escape trainingtank which was brand new in 1953.
My commander in submarinetraining was furious about all the money spent on escape in stead of spending the money teaching people how to operated the subs. Different days I guess.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Mar , 2012, 04:04
Hi Tore

Once again, thank you for your answers. I have got another question - I'm wondering what was your practice to measure the CO2
concentration during longer submerged cruises?
From the reports, I know, the Germans used something called "air sampling tubes, a Drager-measuring apparatus, or an Orsat testing setup".
Was your approach different? Or did you use something similar? If so, could you explain how it worked?
Well Maciek I guess you have to realize this was back in the early fifthies and we did`t have very sofisticated outfit for oxygen and CO2 mesurements except for a box  from the germans with some chemicals which we tried once. I don`t remember what kind of chemicals but it was a fairly simple step to step instructions what to do.
We did`t make any science about it and used our experience and how the body reacted, primarely panting for the excessive CO2 and for oxygen, well honestly we allowed a cigarette per man occasionally (very seldom), if the match wouldn`t ligth we were low on oxygen.
I know most submarines were equipped with testkit, but I doubt if it was regulary used. An experienced submariner can feel a lot on his body about the quality of the air in additon to the time you have been submerged and the activity of the crew.


Well, I supposed it was some kind of chemical tests - thank you for the confirmation.


It is amazing, how small amount of oxygen is needed to keep the man breathing. I have read the memories of polish submariners operating on the Mediterranean. They said, that during long submerged cruise, they also  tried to light the match - and they could't, while they still were able breathing.


They said also, that when they had to use their personal CO2 absorbers,  they had fun making tournaments, which one would be the hottest.


I wonder about another submariners practise - did you have to measure the sea water density during cruises? If so, what kind of equipment did you use?


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2012, 04:29
Maciek
 Well, we never had competitions with the individual CO2 absorbers, they were clumsy and not very comfortable to wear. You are right with regards to the oxygen, we did`t suffer much due to that, it was primarely CO2 which caused the trouble. As a routine everybody who did`t have a watch to attend were lying in their bunks minimizing the oxygenconsumption. It`s unbelievable today to imagine we tried to ligth a cigarette under such conditions.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2012, 04:42
Maciek
Salt density. Yes we measured the salinity (density). Particulary in the waters we were operating, fjords with rivers melting ice etc. It was primarely No1`s reponsibility. As far as I remember it was like a batterygravety measuredevice. Water density was of course important for the trim of the sub.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 06 Mar , 2012, 16:27
Tore-
Do you remember if the torpedomen stored the torpedoes with the contact pistols threaded onto the warheads of the unloaded torpedoes or were they kept locked up and put on prior to loading into the tubes? I know that might be outside the duties of a snort officer, but I wonder if that is something you might have known...
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2012, 23:29
Tore-
Do you remember if the torpedomen stored the torpedoes with the contact pistols threaded onto the warheads of the unloaded torpedoes or were they kept locked up and put on prior to loading into the tubes? I know that might be outside the duties of a snort officer, but I wonder if that is something you might have known...
Christopher
Christopher.
As you say my duty as chief engineer was a bit far from this question, however I`m almost sure they were kept locked up knowing the norwegian procedures for ammo and warheads.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 07 Mar , 2012, 10:50
I was an ammunition and EOD tech in the U.S. Marine corps, and I suspected that was the case. I dealt with ground ordnance and explosives, and never with naval explosives, but I believe the handling procedures were similar. When I stow my below-deck torpedoes I will be sure to keep the pistols in their locker! ;-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2012, 00:04
I was an ammunition and EOD tech in the U.S. Marine corps, and I suspected that was the case. I dealt with ground ordnance and explosives, and never with naval explosives, but I believe the handling procedures were similar. When I stow my below-deck torpedoes I will be sure to keep the pistols in their locker! ;-)
Seems to me the only sensible thing to do. Reloading the tubes was a timeconsuming and noisy job and wouldn`t be done immediately after you have launched your torpedoes. You would rather switch to silent running and sneak away to a safe area where you could reload and hence
the timesaving by having the contact pistols fitted wouldn`t be a point.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Mar , 2012, 02:44
Hi
I also think, that pistols were removed from warheads of the reserve torpedoes. The pistols - especially contact, whiskers type - were rather fragile and in general mess and crowd of the forward torpedo room could be easily damaged.
Moreover, on the following photo of thet forward torpedo room of U-190 (IXC) I have marked the handles which are described by Kohl Fritz and Niestle Axel as the handles for the torpedo pistols.
(http://www.freeimagehosting.net/newuploads/txtri.jpg)


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 08 Mar , 2012, 08:39
Thank you gentlemen - good information!
In the Marine Corps we had similar devices for mortar fuses and large projectiles like 155 mm HE to protect the fuse wells and detonation pistols. I suspect that the devices you circled above were used to manipulate the pistols and protect them while being loaded. A question I would have is where were the pistols stored? On the Type VII there are supposedly water-proof lockers in the aft end of the forward torpedo room. I would guess that they are stored there? Probably there is a similar locker for the aft torpedo room.
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2012, 11:22
Thank you gentlemen - good information!
In the Marine Corps we had similar devices for mortar fuses and large projectiles like 155 mm HE to protect the fuse wells and detonation pistols. I suspect that the devices you circled above were used to manipulate the pistols and protect them while being loaded. A question I would have is where were the pistols stored? On the Type VII there are supposedly water-proof lockers in the aft end of the forward torpedo room. I would guess that they are stored there? Probably there is a similar locker for the aft torpedo room.
Christopher
Christopher
I cannot remember any pistols stored in bulkheadbrackets like on the type IXC- U 190. I guess we normally (in peace time at least) would have stored everything related to this in ammostorage compartment like the ammostorage below COs quarter. Again reloading the tubes with torpedoes having warheads with pistols fitted was not done very often in peacetime we mostly used dummytorpedoes for training. It migth be we would have done it differently in wartime but as I previously said I believe you would have time to fetch them from the ammocompartment when reloading. But I really don`t know as you know it was not my business.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Mar , 2012, 07:03
Hi
I cannot remember any pistols stored in bulkheadbrackets like on the type IXC- U 190. I guess we normally (in peace time at least) would have stored everything related to this in ammostorage compartment like the ammostorage below COs quarter. Again reloading the tubes with torpedoes having warheads with pistols fitted was not done very often in peacetime we mostly used dummytorpedoes for training. It migth be we would have done it differently in wartime but as I previously said I believe you would have time to fetch them from the ammocompartment when reloading. But I really don`t know as you know it was not my business.
Tore, I think you are right - on type VIIC boats the pisols were not stored in that way - mainly because of lack of space. They could be stored in the munition room, below quaters, together with demolishion charges and ammo for the guns.
The brackets from the photo above were used to hold the canisters for the Pi-1 and Pi-2 pistols (as on this photo of the U-190 forward torpedo room, at backboard).
(http://www.hazegray.org/navhist/canada/uboats/u190d.jpg)


Similar canister can be visible on attached photo (U-826 after surrender, while disarming, probably in Loch Lisahally or Loch Ryan). Second photo presents the Pi-2 pistol (combined impact and magnetic type) itself.
--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2012, 07:26
Hi
I cannot remember any pistols stored in bulkheadbrackets like on the type IXC- U 190. I guess we normally (in peace time at least) would have stored everything related to this in ammostorage compartment like the ammostorage below COs quarter. Again reloading the tubes with torpedoes having warheads with pistols fitted was not done very often in peacetime we mostly used dummytorpedoes for training. It migth be we would have done it differently in wartime but as I previously said I believe you would have time to fetch them from the ammocompartment when reloading. But I really don`t know as you know it was not my business.
Tore, I think you are right - on type VIIC boats the pisols were not stored in that way - mainly because of lack of space. They could be stored in the munition room, below quaters, together with demolishion charges and ammo for the guns.
The brackets from the photo above were used to hold the canisters for the Pi-1 and Pi-2 pistols (as on this photo of the U-190 forward torpedo room, at backboard).
(http://www.hazegray.org/navhist/canada/uboats/u190d.jpg)


Similar canister can be visible on attached photo (U-826 after surrender, while disarming, probably in Loch Lisahally or Loch Ryan). Second photo presents the Pi-2 pistol (combined impact and magnetic type) itself.
--
Regards
Maciek
Well Maciek I think we have reached a conclusion to this question. Interesting pictures you posted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2012, 07:54
A few of you guys have in your projects approached the living quarters and the wooden lockers and closets. May be you would take interest in how the private storagesystem worked. The ratings,POs and junior officers had lockers for their personal belongings. The EO and No1 had a wardrobe and the CO both.
The wardrobes and lockers were adjacent to each persons bunk. They were not an ideal place to put your stuff. the humidity was high and all the brass had a tendency to turn green and the textile mouldy. I let the chief-electrician install electric lamps in the lockers, to keep it dry. That helped, but was probably not allowed. But if there are still lamps in the lockers of U 995, please remember that`s not the way it was originally.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 14 Mar , 2012, 11:09
Tore -
I love a good engineer! Well done!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Mar , 2012, 20:14
 Q: Engine Room - Assembly Patch

Tore, I was wondering, did you ever used the assembly patch, to remove the diesel engine, to service them? Or have the original diesel engine always stay within U-995?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Mar , 2012, 22:07
Q: Engine Room - Handle

Tore, was the handle for the Main Air Inlet valve in the engine room painted red?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Mar , 2012, 22:28
Q: Engine Room - Bilges

Tore, on plans for the engine of the Type VIIC
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 00:50
Q: Engine Room - Assembly Patch

Tore, I was wondering, did you ever used the assembly patch, to remove the diesel engine, to service them? Or have the original diesel engine always stay within U-995?
Simon
The dieselengines on all VIICs were heavy and never removed from their shocks. The maintenance was done onboard. In case of major dammages at remote places we did the repairs  by the engineroomcrew and had all kind of spares onboard. Conrod big end bearings dammages were fairly common and on one occasion it resulted in crankpin dammages, We had to grind the crankpin by a homemade tool. Don`t think industrial diesels, the VIICs engines were true marine diesels  and I`m pretty sure the ME of U 995 are the originals, if you are in doubt look at crankpin no3 port engine it is about 2/10 th of a mm smaller than the rest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 00:55
Q: Engine Room - Handle

Tore, was the handle for the Main Air Inlet valve in the engine room painted red?
It was red like all the important pressurehullvalves. Today U 995 look like having measles.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 01:38
Q: Engine Room - Bilges

Tore, on plans for the engine of the Type VIIC
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Mar , 2012, 12:39
Tore, I was thinking about the box keels, and how they would have rested on the sea floor. There seen to be no direct contact between them and the bottom of the keel to help with the load distributions.
 
I was wondering perhaps they were used to restrain that part of the boat while it was in dry-dock being constructed. I imagine that the two engines are very heavy and would put a large amount of stress on the framing around this area.
 
After the engines were installed and just before flooding the dock, they could not remove box keels, so build the keel around them and left them in place.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 14:06
Tore, I was thinking about the box keels, and how they would have rested on the sea floor. There seen to be no direct contact between them and the bottom of the keel to help with the load distributions.
 
I was wondering perhaps they were used to restrain that part of the boat while it was in dry-dock being constructed. I imagine that the two engines are very heavy and would put a large amount of stress on the framing around this area.
 
After the engines were installed and just before flooding the dock, they could not remove box keels, so build the keel around them and left them in place.
Simon
I`m not sure if I understand you correct, may be we are talking about two different things. You sure  have a crossection drawing of the boxkeel which goes all the way from frame 12 to frame 65. You would see it is a very strong thick steelboxshaped "beam"providing a very wide flat seating far wider than a normal ship. Inside the box are thick steelcrossplates placed exactly on the pressurehull where the inside frames are situated all along the flat restingplate on the keel apart from the area were the Kingstonvalves (Flutklappe) are. In addition to that I believe it was a longitudenal centreplate inside the box.This makes it possible to put the sub at the seabottom even when the seabed is a bit rough. When drydocking a normal ship you have to taylorplace wooden blocks so they are placed excactly under the frames for distribution of the stresses and every ship has a dockingplan for that. The sub carries its own foundation along and don`t need that thanks to the long superstrong boxkeel from frame 12 to 65. Another thing is that the sub has almost neutral boyancy hence the weigthstresses are small compared to that of a drydocking. The below picture is of Kaura in drydock resting almost entirely on the boxkeel but have wooden supports on those areas outside the keel illustrates perhaps the drydock question. Please come back if it`s still not clear.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 15 Mar , 2012, 14:10
That photo looks almost as if there is a torpedo in #3!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 14:15
That photo looks almost as if there is a torpedo in #3!
Christopher
No I dont`t think we had a torpedo in the tube. I think they were working on the inside and you see reflection from a lamp.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 15 Mar , 2012, 14:16
I know Tore - I was joking!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 14:29
I know Tore - I was joking!
As a Marine you should know not to joke about ammo that`s seriuos stuff.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 15 Mar , 2012, 14:33
I am entirely sure that the Norwegian Navy is competent enough to remove live ammunition from its tubes before throwing her up on dry-dock! Where else are the torpedomen going to nap during lunchtime? :-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2012, 14:35
I am entirely sure that the Norwegian Navy is competent enough to remove live ammunition from its tubes before throwing her up on dry-dock! Where else are the torpedomen going to nap during lunchtime? :-)
Right Christopher!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2012, 07:53
Simon
I think I understand what you mean. I dont think the two red circled items on your drawing has anything to do with the engine mounting. There are in total 4 such to be seen in the boxkeel between frame 17 and 18,28 and 29 aft and then frame 37-38 and 54-55. The sub was built as described below.
I believe it is a possibility these were openings for the huge liftingstrap when the two pressurehull parts were joined at the slip.
The building of the VIICs was done in the following succession I believe. First the whole boxkeel was placed on a trolley at the slipway. Then the two prerolled curved pressure hull parts appr 125 tonnes each were hanging in a huge crane and joined by welding, followed by frames and smaller steelpieces all welded together, then it was launched and towed to the fittingout quay where the engines were lowered into the hull through pressurehullopenings above the engineroom which were closed by welding.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 16 Mar , 2012, 08:04
I had always wondered what those were also - your description makes it easy to picture its configuration through the box-keel. I just texted and showed the drawing to my sister who worked at one time for a company called Safety Sling, and she had her former engineers confirm that it was probable what they were for. They agree with you! :-)
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2012, 08:17
I had always wondered what those were also - your description makes it easy to picture its configuration through the box-keel. I just texted and showed the drawing to my sister who worked at one time for a company called Safety Sling, and she had her former engineers confirm that it was probable what they were for. They agree with you! :-)
Christopher
Christopher
You certainly have your supportgroup stand by.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 16 Mar , 2012, 08:43
Quote
Christopher
You certainly have your supportgroup stand by.
Tore
Tore - I am just lucky she still has connections - she does not work for those folk any more, but is still on friendly terms. They just happen to provide tools for lifting very heavy industrial type things. :-)
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2012, 09:10
Quote
Christopher
You certainly have your supportgroup stand by.
Tore
Tore - I am just lucky she still has connections - she does not work for those folk any more, but is still on friendly terms. They just happen to provide tools for lifting very heavy industrial type things. :-)
Christopher
In those days before the libertyships and sectionbuildings were common, heavy lifts of 100-150 tonnes were not done at every yard. The germans were pretty advanced  not only  technically but productionwise as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Mar , 2012, 10:59
Thanks, guys!  :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2012, 04:58
Further to the question of the holes in the boxkeel center plate. I found a description as to the way VIICs were built at Blohm & Voss shipyard. If you go to http://www.uboatarchive.net/U-93INT.htm (http://www.uboatarchive.net/U-93INT.htm) (an interrogation report) you will find a description of the stages of the VIIC construction on page 19 and 20 which pretty much support our theory.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2012, 14:56
Q: Engine Room - Flooring

Tore, did the original flooring in the engine room have draining holes like the conning tower floor (Right) or was it solid (Left)?

(http://img215.imageshack.us/img215/5509/graphic1pb.jpg)

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2012, 15:13
Q: Engine Room - Photograph

Tore, in the original wartime photograph below, someone is checking diesel level in the engine room (I am sure a job you did a few 100
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 31 Mar , 2012, 16:00
Simon,
It looks like a linked rubber matte, possibly anti-slip, fatigue reduction, or for sound reduction. It might be for all of the above! We had similar mattes in our machine shop.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2012, 16:36
Simon,
It looks like a linked rubber matte, possibly anti-slip, fatigue reduction, or for sound reduction. It might be for all of the above! We had similar mattes in our machine shop.

I see what you are talking about  :)

I have spend two years looking at this picture try to workout that it is  :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2012, 23:48
Q: Engine Room - Flooring

Tore, did the original flooring in the engine room have draining holes like the conning tower floor (Right) or was it solid (Left)?

(http://img215.imageshack.us/img215/5509/graphic1pb.jpg)

Thanks, Simon.
Simon
There were no drainholes, your left picture is correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2012, 00:07
Q: Engine Room - Photograph

Tore, in the original wartime photograph below, someone is checking diesel level in the engine room (I am sure a job you did a few 100
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Apr , 2012, 13:19
Well
In this country easter has already started and people are moving up to the mountains for the last skiingoportunity. So I`m sending you my greetings below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Apr , 2012, 14:00
Well
In this country easter has already started and people are moving up to the mountains for the last skiingoportunity. So I`m sending you my greetings below.
Tore

Thanks for the nice seasonal greetings! It funny to hear you talk about people moving to the mountains for there last opportunity to go skiing. As I am getting ready for my 23rd winter as a avalanche forecaster down here in New Zealand  :D


Tore, thanks for all your time and help over the last few months.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Apr , 2012, 14:36
Thanks Simon.
Good luck with your coming winterseason, we had one of our worst avalanche winters, I`m happy it`s over. Central european skiers having very little knowledge of avalanches are going off pisteskiing and creating a lot of problems. Quite a few have been killed this season in spite of all the avalanchegadges they have.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Apr , 2012, 16:12
Hi Tore


I have got question about diving planes angle indicators. I know, that each diving planes control station has its own angle indicators - one pure electrical (resistance bridge principle) and one pure mechanical (called Teleflex system). Could you explain how this latter works? I can not find any appropriate references to the Teleflex system.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Apr , 2012, 01:26
Hi Tore


I have got question about diving planes angle indicators. I know, that each diving planes control station has its own angle indicators - one pure electrical (resistance bridge principle) and one pure mechanical (called Teleflex system). Could you explain how this latter works? I can not find any appropriate references to the Teleflex system.


--
Thanks, regards
Maciek
Maciek
I have been trying to figure out about a 2nd mechanical indicator system for the hydroplanes operators in the CR and I simply cannot remember to have seen them. Teleflex is a well known make even today and exsisted in the wartime. At that time the system was basically a flexible cable in an armed hose for transmitting mechanical power. We had once a failure on the fwd hydroplaneindicator on the ex. U 995 and I remember crawling in the fwd torpedoroomarea discovering that the mechanical transmissionlink from the hyroplanerod to the electro transmitter was broken. It could have been a teleflex. But I am sorry I cannot remember a mechanical (Teleflex) connection to the hydroplaneindicators in the controlroom, it should be possible to see the teleflexcable on one of the photos.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Apr , 2012, 01:51
Marko
I have been looking on the photos I have and think I found the mechanical hydroplane indicator. See my bad photo below. It is a rather crude (aluminum?) disc below and sligthly to the left of the electrical indicator. I guess you migth be able to see it better on one of the panaorama photos on the net.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Apr , 2012, 03:07
Tore
I have been trying to figure out about a 2nd mechanical indicator system for the hydroplanes operators in the CR and I simply cannot remember to have seen them. Teleflex is a well known make even today and exsisted in the wartime. At that time the system was basically a flexible cable in an armed hose for transmitting mechanical power.

Well, I have found following description (Type IXC Design Study, http://uboatarchive.net/DesignStudiesTypeIXC.htm (http://uboatarchive.net/DesignStudiesTypeIXC.htm)):
Quote
f.  Mechanical Bow Plane Angle Indicator System     
This system is identical with the Teleflex systems installed in USN surface vessels in various applications and is so called by the Germans.  Details of the system may be obtained from any Teleflex instruction book.


When I wonder about this a bit longer, I guess, even name "Teleflex" indicates the flexible cable, as you have written, so I pretty sure, you are right.
But I am sorry I cannot remember a mechanical (Teleflex) connection to the hydroplaneindicators in the controlroom, it should be possible to see the teleflexcable on one of the photos.
I have attached some photos (one from U505, other from U995), but I also cannot see flexible cable.
And one more photo from U570:
(http://uboatarchive.net/U-570Photo19.jpg)




--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Apr , 2012, 06:16
Maciek
On your picture of the hydroplanecontrols on U 995 I think there is a cable going through the fwd pressurebulkhead which migth be the teleflexcable for the fwd hydroplanes, it has the proper curvature, size and a possible correct position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 05 Apr , 2012, 03:35
Wow, I get a little busy and  I miss a million posts! This is very late, but way back up there, that sure DOES look liked a linked rubber mat. Now I'm no Tore, my experience with them is rather mundane. Just out of high school my family had a welcome matt that was just the same...linked strips of rubber, held together with metal pins. My girlfriend came over for New Years with her, uh, larger friend. The friend was the one who knocked on the door...so I opened it, and she stepped inside and her high heel caught in the gap between strips and she fell forward on top of me...I threw out my hands to both stop her from falling and stop myself from being knocked over, instinct...I caught her on both very large boobs, we twisted sideways and almost fell, and then all was well, but we were red faced and laughing. The basic effect was: open door, FALL OH MY GOD! GRAB! TWIST! STUMBLE!

Anyway, stupid mat.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2012, 04:42
Well Wink, the mat we had wasn`t instrumental in getting our hands full of what you got. Poor us had our hands full of ligth alloy pistons with heavy conrods which very easy could be dammaged when lowered on to the steel floorplates.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Apr , 2012, 05:55
Just as a side note to the discussion about rubber matting ... The above mentioned  http://uboatarchive.net/DesignStudiesTypeIXC.htm says "           ... Linoleum deck covering is provided in the living spaces and in the torpedo rooms.  Linoleum over wood decking is provided in the sound and radio rooms.  Rubber link matting is provided in the maneuvering room, engine rooms and control room...    "
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2012, 08:36
Just as a side note to the discussion about rubber matting ... The above mentioned  http://uboatarchive.net/DesignStudiesTypeIXC.htm (http://uboatarchive.net/DesignStudiesTypeIXC.htm) says "           ... Linoleum deck covering is provided in the living spaces and in the torpedo rooms.  Linoleum over wood decking is provided in the sound and radio rooms.  Rubber link matting is provided in the maneuvering room, engine rooms and control room...    "
Christopher
Christopher
I guess floorcoverings were commonly used in the wartime, mainly for soundreduction. We didn`t have mats to cover the floor to the same extent as mentioned in the report you quoted. I think the mats were of variable design as may be seen below on the wartime photo of the floorplates in a VIIC controlroom. To me it looks like some kind of woven mats. The forward torpedoroom (livingquarters) had steelframed hatches see photo below and it could very well be linoleum within the frames. As far as I remember it was the same in the wardroom, COs quarter, CPOs and POs mess as well, not so many hatches though. The floor in the control room was steelplates. In the engineroom we didn`t have any mats only steelplates except during major overhauls. In the E-room I think it was steelplates as well and in the aft torpedoroom I cannot remember.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2012, 09:30
Further to my last post I am posting  a picture of the E-room floorplating including aft torpedofloorplating and engineroomfloorplating on KNM Kaura, it should be as originally fitted.
It looks to me as steelplates all over, but remember this was not wartime and the german had probably mats covering the steel floorplates.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Apr , 2012, 14:07
Q: Engine Room - Lubricating caps

Tore, it seen that most lubricating caps are painted red (like in Engineroom floorplating.jpg), but can you remember if the lubricating caps were made of bronze?

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Apr , 2012, 14:12
Q: Engine Room - Piping

Tore, is the lower pipe copper, and the upper pipe brass? As there seem to be a big colour different between the two pipes ???

Thanks, Simon.

(http://img594.imageshack.us/img594/5944/new1zx.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Apr , 2012, 14:52
Q: Engine Room - Piping

Tore, is the lower pipe copper, and the upper pipe bronze? As there seem to be a big colour different between the two pipes ???

Thanks, Simon.

(http://img594.imageshack.us/img594/5944/new1zx.jpg)

I was looking at a few more pictures of pipes within the engine room, and I think the copper section is a small patch to replace a small section of missing piping :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Apr , 2012, 18:14
Q: Engine Room - Fuel filters

Tore, perhaps can help me with a discussion I had several years back. There are two different types of fuel filters on the engines. I was wondering if you know if one is an original German fuel filters.

Many thanks again, Simon.

(http://img707.imageshack.us/img707/9392/new1ut.jpg)
Fig. 1. Port side fuel filters.

(http://img221.imageshack.us/img221/3606/new2tyi.jpg)
Fig. 2. Starboard side fuel filters.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Apr , 2012, 23:51
Q: Engine Room - Lubricating caps

Tore, it seen that most lubricating caps are painted red (like in Engineroom floorplating.jpg), but can you remember if the lubricating caps were made of bronze?

Thanks, Simon.
Simon
Lubricating caps. Upon your remarks I rechecked my pictures and realized they are most probably from the late 60 ties thus after my time. Painting details like nuts, cocks and cups were often a popular pastime activity amongst the engineroomcrew during boring watches. As a chief engineer I did`t
encourage such paintings particulary the use of red which was primarely reserved for essentials like pressurehullvalves, ballasttank vents etc. I realize present day U 995 have red paints all over, we avoided that in my time and the original paints on our VII C did`t have all these "red dots". Neither did we have the usual shiny brass details as you see on f.i. british subs  primarely because the germans didn`t use copper and brass to the same extent.
I guess I`m trying to answer: they were possibly of steel and painted in the same colour as the engines, grey.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2012, 00:15
Q: Engine Room - Piping

Tore, is the lower pipe copper, and the upper pipe brass? As there seem to be a big colour different between the two pipes ???

Thanks, Simon.

(http://img594.imageshack.us/img594/5944/new1zx.jpg)
Indeed the lower pipe seems to be copper. As far as I remember most of the pipings were steel and I don`t think the other pipe is brass nor copper, I`ll make a guess it`s rusty steel having been washed with oil, but that`s a guess (hopefully it isn`t plastic).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2012, 00:29
Q: Engine Room - Fuel filters

Tore, perhaps can help me with a discussion I had several years back. There are two different types of fuel filters on the engines. I was wondering if you know if one is an original German fuel filters.

Many thanks again, Simon.

(http://img707.imageshack.us/img707/9392/new1ut.jpg)
Fig. 1. Port side fuel filters.

(http://img221.imageshack.us/img221/3606/new2tyi.jpg)
Fig. 2. Starboard side fuel filters.
Simon.
There is something odd with the pictures of the filters none of them look like the originals, do you happen to have a complete picture of the port filter?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2012, 00:37
Simon.
Your piping question. If you have a close look at the engine manoeuvreing handles, they were steel, on your filterpictures you`ll see they have same colour as the pipe I assumed was steel. I guess that support the steel theory.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Apr , 2012, 01:02
Simon.
Your piping question. If you have a close look at the engine manoeuvreing handles, they were steel, on your filterpictures you`ll see they have same colour as the pipe I assumed was steel. I guess that support the steel theory.
Tore

Thanks, Tore.

This is very useful to know. I will have to change numerous of my piping around the engines. As I base many of the piping on this bronze colour.
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2012, 05:55
Simon
Painting. Just a comment to your pipeline photo. As I previously has mentioned I dislike all the funny painting done on the present U 995. Below I have indicated by arrows a wrong painting which would harm the operation of the main engines. The bundle of four arrows points at the fuelpumpregulatingrods. They are rods going to each individual HP fuelpumps and by movement back and forth turns the fuelpump plunger and by that regulating the fuel to each individual cylinder, hence the output of the engines. Any paints on these rods would cause the rodlinks to stick. Any engineer would see to it that they were freed from any coating, rust or anything which could obstruct the free movement. They were all the time shiny metallic and carefully oiled.
The other picture points to the inlet- and exhaustvalverockers pushrod from the camshaft. Any paint would harm the oilsealing to the camshaftcasing and the engineers would keep them shiny and well oiled. So anybody making drawings or models should not copy the present days painting on the U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Apr , 2012, 14:15
Thanks, again for the great information. It
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2012, 14:50
Simon
I`m happy to be able to assist. However don`t make every pipe shiny they were not, most of them were painted grey. The hp pipes from the Bosch fuelpumps to the fuelinjectors were not painted and the indicatorcocks were black steel and with a tendency to have a few rusty spots as they were subject to the exhausttemperatures. Looking forward to be seeing your enginedrawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Apr , 2012, 19:21
1. What is this? Is it a small window to check fuel level? What colour should it be?
2. What is this? Is it a small coverplate? It very hard to tell from these pictures as with the paint, but are there two very small screw on each side of the plate?
3. Just noted this reset in the rods this afternoon. I imagine this would illustrate the maximum movement of the rods.

Also just realise I have a major redraw on the fuel pump regulating rods!!! :o :o :o I do not realise that the fuel pump regulating rods are not symmetrical on the aft three heads of the engine, compare to the fore 3 heads. By the way, Tore how did you number the head, from stern to bow.

Thanks, Simon.

(http://img600.imageshack.us/img600/8931/new3r.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Apr , 2012, 23:24
Tore, what is the red thing?

(http://img713.imageshack.us/img713/8017/new1t.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 00:23
1. What is this? Is it a small window to check fuel level? What colour should it be?
2. What is this? Is it a small coverplate? It very hard to tell from these pictures as with the paint, but are there two very small screw on each side of the plate?
3. Just noted this reset in the rods this afternoon. I imagine this would illustrate the maximum movement of the rods.

Also just realise I have a major redraw on the fuel pump regulating rods!!! :o :o :o I do not realise that the fuel pump regulating rods are not symmetrical on the aft three heads of the engine, compare to the fore 3 heads. By the way, Tore how did you number the head, from stern to bow.

Thanks, Simon.

(http://img600.imageshack.us/img600/8931/new3r.jpg)
Simon
1. This is an "inspection window" where you can check the movement of the fuelplunger in the fuelpump. It should never be painted. Usually the fuelpumps were painted black from the Bosch manufacturer.
2. Honestly I cannot remember this signplate. It could be nameplate for the Bosch factory, as the HP fuelpumps could be moved around it was not a cylinder numberplate.
3.This is a toothed rack entering a toothed rim on the fuelplunger outer sleeve connected to the plunger, regulating the fuelinjection by turning the sleeve and plunger. The movement was strictly horisontal, back and forth and the recess is presumably a guide to prevent it turning.
For the position of the fuelpumprack it was usually an engraved millimeterscale on the rack just before entering the fuelpump. I think you can see marks  on the rigth side of the pumpcasing were the pointer was fitted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 00:40
Simon
The cylinders were numbered from forward to aft. The fuelrack linkage is very important. If you look carefully on your pictures you`ll see each individual pump has a linkconnection with an oval slot in the rod and a spring attached, The spring seems to be missing on quite a few pumps on your picture. The system works like this: if one fuelpumpplunger is stuck (scored) the governor or maneouveringhandle should be able to move the rack so the rest of the pumps could be moved to 0 stopping the engine and prevent overspeeding. In drawing the fuelrack don`t forget the governor at the aft end of the rack.
Tore       
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 00:45
Tore, what is the red thing?

(http://img713.imageshack.us/img713/8017/new1t.jpg)
Simon
This is a small screwvalve for "bleeding" the fuelpump eg to get rid of air in the fuelpump. It is wrongly painted red.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 01:04
Looking at all the pictures of the fuelpumps it strikes me that every nut and connection is painted. The connection between the HP fuelpump and the fuelinjector in the cylindercover was comparatively often dismantled. The fuelinjectors were sensitive and had to be changed (overhauled) quite frequently. The last thing you wanted to have was paintflakes entering you delicate fuelsystem particulary after the filters. Therefore the connection from the fuelpumps to the fuelinjectors fitted in the cylindercovers should not have any paint and should be clean steel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 01:32
Simon
You observation fuelrack is not symmetrical.
The fuelrack is controlled by two means, the maneuovringstand in front of the engine and the governor in the aft. The governor takes care of the stable revs at varying loads and particulary in bad weather is a must. The maneuveringstand overule the governor anytime you want. In order to accommodate the linkage to the governor in the aft end, they reversed the linkage at the center of the engine as you correctly observed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Apr , 2012, 03:22
1. What is this? Is it a small window to check fuel level? What colour should it be?
2. What is this? Is it a small coverplate? It very hard to tell from these pictures as with the paint, but are there two very small screw on each side of the plate?
3. Just noted this reset in the rods this afternoon. I imagine this would illustrate the maximum movement of the rods.

Also just realise I have a major redraw on the fuel pump regulating rods!!! :o :o :o I do not realise that the fuel pump regulating rods are not symmetrical on the aft three heads of the engine, compare to the fore 3 heads. By the way, Tore how did you number the head, from stern to bow.

Thanks, Simon.

(http://img600.imageshack.us/img600/8931/new3r.jpg)
Simon
1. This is an "inspection window" where you can check the movement of the fuelplunger in the fuelpump. It should never be painted. Usually the           fuelpumps were painted black from the Bosch manufacturer.
2. Honestly I cannot remember this signplate. It could be nameplate for the Bosch factory, as the HP fuelpumps could be moved around it was not a cylinder numberplate.
3.This is a toothed rack entering a toothed rim on the fuelplunger sleeve, regulating the fuelinjection by turning the sleeve. The movement was strictly horisontal, back and forth and the recess is presumably a guide to prevent it turning.
For the position of the fuelpumprack it was usually an engraved millimeterscale on the rack just before entering the fuelpump. I think you can see marks  on the rigth side of the pumpcasing were the pointer was fitted.
Tore

Number 2:

Tore, I think you are correct about the Bosch factory name plate  :)

Could not found any u-boat wartime pictures of this plate :'( So I base the plate below on two wartime Bosch factory name plate from a horn & a magneto ;D They were the only wartime name plate I could found on the net.

(http://img404.imageshack.us/img404/3649/new4j.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 04:29
1. What is this? Is it a small window to check fuel level? What colour should it be?
2. What is this? Is it a small coverplate? It very hard to tell from these pictures as with the paint, but are there two very small screw on each side of the plate?
3. Just noted this reset in the rods this afternoon. I imagine this would illustrate the maximum movement of the rods.

Also just realise I have a major redraw on the fuel pump regulating rods!!! :o :o :o I do not realise that the fuel pump regulating rods are not symmetrical on the aft three heads of the engine, compare to the fore 3 heads. By the way, Tore how did you number the head, from stern to bow.

Thanks, Simon.

(http://img600.imageshack.us/img600/8931/new3r.jpg)
Simon
1. This is an "inspection window" where you can check the movement of the fuelplunger in the fuelpump. It should never be painted. Usually the           fuelpumps were painted black from the Bosch manufacturer.
2. Honestly I cannot remember this signplate. It could be nameplate for the Bosch factory, as the HP fuelpumps could be moved around it was not a cylinder numberplate.
3.This is a toothed rack entering a toothed rim on the fuelplunger outer sleeve and , regulating the fuelinjection by turning the outersleeve and then the fuelplunger. The movement was strictly horisontal, back and forth and the recess is presumably a guide to prevent it turning.
For the position of the fuelpumprack it was usually an engraved millimeterscale on the rack just before entering the fuelpump. I think you can see marks  on the rigth side of the pumpcasing were the pointer was fitted.
Tore

Number 2:

Tore, I think you are correct about the Bosch factory name plate  :)

Could not found any u-boat wartime pictures of this plate :'( So I base the plate below on two wartime Bosch factory name plate from a horn & a magneto ;D They were the only wartime name plate I could found on the net.

(http://img404.imageshack.us/img404/3649/new4j.jpg)
Simon
I don`t think there was much difference between the two pumpexecution externally, neither the nameplate. The serialno on the nameplate was not too important, what really matters was the interior parts, plunger and liner, which was lapped together and could be dismantled as a unit from the housing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 07:20
Simon
While beeing on the subject of pushrods for the valve rockerarms I realize I have not mentioned a 3rd valvepushrod per cylinder. The red arrow on the picture below indicate the the rod. This is the rod operating the startingvalverockerarm. Normally it is kept free from the camshaft by a spring but when the startinghandle is placed in start position, the rod is pneumatically pushed against the springpressure down to the camshaft which then control the compressed air to the individual cylinders and thus starts the engine by compressed air. As the the other valverods, this should be shiny metallic as well and not painted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Apr , 2012, 14:11
(http://img534.imageshack.us/img534/1410/pump1p.jpg) (http://img43.imageshack.us/img43/1914/pump2i.jpg)
Fig. 1. New updated fuel pump. Old fuel pump (right).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 14:36
Seems to be fine to me. If you really want details your could put in fuelrack positionmarks 1mm apart as indicated in red below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2012, 14:50
The threaded parts on the rack linkageconnection showed on your new drawing was for adjusting the individual pumps fuelinjection in relation to the others, and the fuelrack markings was very useful for that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Apr , 2012, 14:58
Seems to be fine to me. If you really want details your could put in fuelrack positionmarks 1mm apart as indicated in red below.
Tore

Yes, love is kind of detail!!  :) :)

I added this level of detail already; added marks for the dip stick for the oil tank between the two engines  ;D ;D
 

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Apr , 2012, 15:05
Q: Engine Room - Fuel filters

Tore, perhaps can help me with a discussion I had several years back. There are two different types of fuel filters on the engines. I was wondering if you know if one is an original German fuel filters.

Many thanks again, Simon.

(http://img707.imageshack.us/img707/9392/new1ut.jpg)
Fig. 1. Port side fuel filters.

(http://img221.imageshack.us/img221/3606/new2tyi.jpg)
Fig. 2. Starboard side fuel filters.
Simon.
There is something odd with the pictures of the filters none of them look like the originals, do you happen to have a complete picture of the port filter?
Tore

Tore, here a better view of the port filters

(http://img193.imageshack.us/img193/2995/new1gi.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 01:15
Simon
Fuelfilters. I have been trying to figure out the filterquestion but cannot remember the details, so I`m back to guessing. The stb. filters does not give me a clue whereas on the port I remember the logo on the filtercasing. I`ll go for 60% chance port filter could be the original. Sorry not a very good answer I`m afraid.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Apr , 2012, 08:22
Hi


Maybe you'll find it useful.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 10:10
Yes Maciek, you see the plunger with the helic, the gearrim turning the outer sleeve and hence the plunger. You even see the fuelrack markings, the guidescrew in the rack slot and the lockingscrew for the lapped plungerbarrel. You`ll get everything correct to tiniest detail Simon.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 10:56
Simon.   I have marked the details of Macieks drawings transfered to the outside of your pumpcasing as below. I guess your drawing is pretty much correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Apr , 2012, 12:11
Hi


Maybe you'll find it useful.


--
Regards
Maciek

Hi Maciek

What book are these drawing from?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Apr , 2012, 13:06
(http://img42.imageshack.us/img42/5520/layout2ng.jpg)
Fig. 1. This was my old layout of the fuel pumps.

(http://img818.imageshack.us/img818/3512/layout1p.jpg)
Fig. 2. This is the corrent layout for the fuel pumps for the port engine.

(http://img812.imageshack.us/img812/882/layout4i.jpg)
Fig. 3. Close-up view of one fuel pump.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 14:40
Very good ! And the fuelrack transmission studs are placed correctly in contact with the end of the oval slots in the fuelrack link. As far as I can see you have incorporated a flexible link in the fuelracklinkage. For some reason stb engine of the U 995 has two flexible links, one is actually double. I have indicated the two linkpositions on the posted picture below.The linkage is as you see, pretty rough and in order to have a smooth transmission it could possibly have been necessary to have an extra flexible link. I didn`t put it in. My suggestion would be to have only one flexible link per engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 15:24
A small remark on the fuelpumps. The arrangement for the fuelpumps is of course for the stb engine, for the port engine the fuelpumps shall be the opposite e.g. the fuelrack positionmarks are pointing forward and the movement of the fuelracklink is opposite the stb link. The reason is that the fuelpumps are not in "mirror execution".
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 13 Apr , 2012, 15:36
Tore -
I have noticed in my study of the forward torpedo room that there were many fixtures that were as you say "in mirror execution" - pieces that seem to have been designed for a given function on the port side, but could not be switched to the stb side. That indicates the there were a left and a right to many pieces of equipment. But other pieces are designed to have one model that works either way. That could be a supply nightmare I would think!
Was there a lot on the U-995/KNM Kaura that showed "mirror" design, if you can recall?
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Apr , 2012, 18:14
Hi Tore

What is this? And why are there three pipings leading to it?

Thanks, Simon

(http://img853.imageshack.us/img853/3685/new1c.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2012, 23:45
Tore -
I have noticed in my study of the forward torpedo room that there were many fixtures that were as you say "in mirror execution" - pieces that seem to have been designed for a given function on the port side, but could not be switched to the stb side. That indicates the there were a left and a right to many pieces of equipment. But other pieces are designed to have one model that works either way. That could be a supply nightmare I would think!
Was there a lot on the U-995/KNM Kaura that showed "mirror" design, if you can recall?
Christopher
Christopher
You are rigth. The logistic would be a nigthmare with mirror executions and particulary on a sub. Fulepumps is a good example, fuelinjectionparts are sensitve, important parts which need to be exchanged comparatively frequent. If f.i. the fuelpumps were in mirror execution you had to store twice as much onboard  in restricted space. It was easier to adapt the movement of the fuelrack. There were not many mirrorexecutions on KNM Kaura ex U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2012, 00:39
Hi Tore

What is this? And why are there three pipings leading to it?

Thanks, Simon

(http://img853.imageshack.us/img853/3685/new1c.jpg)
Simon
I cannot see all the details, but I believe it is a hydraulic amplifyer on the fuellink. The centrifugal governor should be fitted in the aft end, I believe geardriven from the camshaft, I don`t remember the details but the system works like this: the springloaded sentrifugal weigths of the governor are forced in and out by the engine revs. pulling an oilslide up and down feeding oil under pressure from the luboilsystem to a piston in the amplifyer which then is moving the fuellinkage and HP fuelpumpracks maintaining the revs of the engine. I believe you can see an  adjustingscrew on the anglelever for adjusting the linkage in relation to the amplifyer (governor). The pipes should the be luboilpipes coming from the governor/luboilpump and returning to luboiltank. The system could be overruled from the maneuvringstand
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2012, 00:44
Simon
The little red knob on top of the amplifyer is a bleedingcock for deaerating the oilsystem. It shouldn`t be red.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2012, 00:59
Simon
Sometimes a simple sketch explains more than words and I`m posting a sketch as a follow up of my story.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2012, 02:10
A small remark on the fuelpumps. The arrangement for the fuelpumps is of course for the stb engine, for the port engine the fuelpumps shall be the opposite e.g. the fuelrack positionmarks are pointing forward and the movement of the fuelracklink is opposite the stb link. The reason is that the fuelpumps are not in "mirror execution".
Tore
Simon
 I am sorry, you are quite rigth it is the port engine, I see you have connected the fuelpumps for cyl 4 and 5 which means you have bow to the rigth, I`m used to have the bow to the left, sorry for the confusion. When the governor(amplifyer) is hooked up there will be no confusion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2012, 06:43
Fuelrack
I realize the schematic sketch of the governor can be a bit confusing as the amplifyer is in mechanical connection with the governor whereas on the engine it is hydraulically connected. I `m posting a systemsketch which is more relevant to our system which migth give you a better understanding. Please forgive me for acting like a tutor, it is not my meaning at all, but I guess a draugthsman make a better drawing when understanding the working of the components.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Apr , 2012, 08:16
Hi
What book are these drawing from?
I can't remember - I got when I had been working on the U Bootskunde f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Apr , 2012, 11:06
Simon
As usual Maciek comes up with a lot of exellent drawings which are all better than my memory. It migth be a bit complicated to incorporate all this in your drawings as long as you don`t shall have a crossection drawing of the engines, so it migth be an idea to simplify it to the external parts. On the drawing below I have indicated where the mechanical connection ( not hydraulic) from the governor comes out of the camshaftcasing and operating the slidelever which is hinged in such a way that it stabilize the piston (and fuelrack) in the new position created by the sentrifugalforces on the governor. The slide is connected to two pipes, the top pipe is returnoil to the luboilsump tank, the lower is the fresh luboil pressure from the pump forward (see drawing below) I guess both goes to the aft before they connect up to their sources. The movement of the amplifierod is then transmitting the new position to the fuelracklinkage in a simple way seen on one of your photographs. I guess you have to observe that the fuelracklinks of stb engine goes the other way and hence it would be a different linkage on the stb side.I think you can see it partly on panorama picture from Laboe, may be you have a better picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Apr , 2012, 14:21
(http://img560.imageshack.us/img560/924/fuelpump.jpg) (http://imageshack.us/photo/my-images/560/fuelpump.jpg/)
Click picture to view in full view.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 00:13
Simon
Very good!
A few remarks, the link from the governor (in the camshaftcasing) is connected to a "scalearm" with a pivot seen as a screw on the servomotor pedestall, on the other side at the scalearm is a vertical thin rod operating the slide, this rod can be seen a just a little left of the servomotor (amplifier) rod going vertically down to the fuelrackleverarm. The very visible oilpipes are marked on my drawing below. There are only two pipes, supply and return. On the fwd side of the fuelracklink you have the cylinderliner lubricator driven by an arm from the fwd valverocker pushrodconnection driving the lubricator via a ratchetconnection. The pipes from lubricator are two per cylinder. The fuelracklink is connected to the fuelhandle on the maneuvring stand, I don`t think you should have any oval slots in that link as you want a precise movement and no slack. I cannot remember the excact linkage but may be you have a picture to share. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 00:57
Simon
I realize i should probably elaborate a little more on the lubricator. They are small plungers (12 per lubricator) pumping droplets to be seen through the front sigthglass so you can ascertain  each cylinder is lubricated. I have added a few details on the drawning below hopefully to make it clearer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Apr , 2012, 04:03
The fuelracklink is connected to the fuelhandle on the maneuvring stand, I don`t think you should have any oval slots in that link as you want a precise movement and no slack. I cannot remember the excact linkage but may be you have a picture to share. 

Hi Tore

I only have one very poor picture of this area. I thought it was not correct to have an oval slot. But if you look at the picture below, just to the left of the connected, there look like a very small oval slots. What do you think?

(http://img23.imageshack.us/img23/9817/new1dv.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Apr , 2012, 04:11
Simon
Very good!
A few remarks, the link from the governor (in the camshaftcasing) is connected to a "scalearm" with a pivot seen as a screw on the servomotor pedestall, on the other side at the scalearm is a vertical thin rod operating the slide, this rod can be seen a just a little left of the servomotor (amplifier) rod going vertically down to the fuelrackleverarm. The very visible oilpipes are marked on my drawing below. There are only two pipes, supply and return. On the fwd side of the fuelracklink you have the cylinderliner lubricator driven by an arm from the fwd valverocker pushrodconnection driving the lubricator via a ratchetconnection. The pipes from lubricator are two per cylinder. The fuelracklink is connected to the fuelhandle on the maneuvring stand, I don`t think you should have any oval slots in that link as you want a precise movement and no slack. I cannot remember the excact linkage but may be you have a picture to share. 
Tore

Thanks for the feedback  :) :)
 
I forgot about the slide rod to the fuel rack lever arm, I will add this in a few days.
 
I have drawn all the other detail you talked about above but they are on different layers of the drawing. That is why they are not display in this drawing. I will combare the layers and post pictures soon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Apr , 2012, 04:23
Tore, today I was updating these two piping on my drawing. Are they oil return pipes?

(http://img137.imageshack.us/img137/5800/new2e.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 06:00
The fuelracklink is connected to the fuelhandle on the maneuvring stand, I don`t think you should have any oval slots in that link as you want a precise movement and no slack. I cannot remember the excact linkage but may be you have a picture to share. 

Hi Tore

I only have one very poor picture of this area. I thought it was not correct to have an oval slot. But if you look at the picture below, just to the left of the connected, there look like a very small oval slots. What do you think?

(http://img23.imageshack.us/img23/9817/new1dv.jpg)
We see only the part of the fuellinkage belonging to fuelpump no 1.so the oval slot belongs to the no1 fuelpumplink and is OK there are further linkages going down to the linkagesupport and a link disappearing towards the center of the enginefront connecting to the fuelhandle with some interlocks etc which is not visible and very complicated to incorporate. My advice is to show the lingkage as drawn, but add the pedestallinkage as you migth be able to figure out looking at my two drawings below
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 06:24
Tore, today I was updating these two piping on my drawing. Are they oil return pipes?

(http://img137.imageshack.us/img137/5800/new2e.jpg)
Simon
No, the visible part of the luboil pipes to and from fuelrod servomotor is going down and aft, then I guess the supply pipe is coming from the luboil linebranch just after  the oilcooler up front and is fitted under the floorplates and the return pipe goes to the valvechest under the floor where is is distributed to lubil tanks stb and port. As far as I can see the pipe you are pointing out is cylindercover coolingwater pipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 09:11
Simon
The lubricator ratchetlever is fitted with holes for capacityadjustment, see picture below.The starting- and fuelhandles are marked as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2012, 09:31
As a follow up of the lubricator I`m posting a cross section drawing explaining the working.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2012, 03:00
Simon
Looking at your last post, I wasn`t sure you got my idea about the governor servomotor oilpipes OK so I post a couple of pictures marking off the pipes. Both pipes, not three, are bundled together as shown and goes aft along the roots blowercasing (fixed to that) to about middle of the housing (sorry no picture) then goes down and disappear under the floor where the return (blue) joins the main engine returnoilpipe. The luboilpressurepipe I believe goes under the floor up front to the branch off  just after the luboilcooler marked red on the systemsketch. The returnpipes are marked blue.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2012, 08:44
Governor servomotor supply and return oilpipes.
Simon finally I got hold of a photo showing the two pipes previously discussed. As you see on the picture below they are bundled together and fixed to the Roots blower before going down under the floor as mentioned before.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 May , 2012, 05:17
Tore


Being in the aft torpedo room topic - do you remember, what is this device?

(http://img641.imageshack.us/img641/4143/gerat1.jpg)


It is connected by means of the wheel gear with the handle:

(http://img848.imageshack.us/img848/8903/gerat2.jpg)


General view:

(http://img217.imageshack.us/img217/936/gerat3.jpg)



--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 May , 2012, 05:53
Tore,
on one of your drawing you have marked the location of th air coolers for E-motors:

(http://img525.imageshack.us/img525/3888/288ig.jpg)



Could you mark theirs location on the horizontal cross-section? I wonder, where are they fitted.
The same request about the electrically driven cooling water pump, which enabled water circulation during submerged cruise.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2012, 10:07
Maciek
For some reason your pictures came out as a red x on my computer. So I have to comment based on your text. It could be the exhaust outlet from the Junker compressor as far as I remember it was operated by a valve wheel with a spindle for grinding the carbon deposits by hand,not airmotor as for the mainengines.
Tore












Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2012, 10:34
E-motorcoolers
I believe the coolers No1 & 2 stb as well as no 1 & 2 port were placed under the stored torpedo towards the centerline, but I`m not 110% sure.
On the crossection drw of U570 in the E compartment are two circles which I believe could be the stb and port coolers.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2012, 10:39
Sorry I`m currently on my little farm in very remote area where my internet connection sometime is very bad. Today is one of those days so I have some problem in sending and recieving pictures right now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 May , 2012, 11:44
Tore


Thank you very much for your answer.


For some reason your pictures came out as a red x on my computer. So I have to comment based on your text.


I moved the pictures into another server, maybe now they will be visible.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2012, 23:13
Thanks Maciek i got the pictures. I believe it`s what i said.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2012, 23:50
Maciek
I forgot your coolingwater pump question. I believe it`s fitted on port side rigth where the emergencysteering wheel is stowed. It`s a relatively small centrifugal circulation pump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 May , 2012, 08:14
Hi Tore
It could be the exhaust outlet from the Junker compressor as far as I remember it was operated by a valve wheel with a spindle for grinding the carbon deposits by hand,not airmotor as for the mainengines.


I have found following description in the British Report on U-570 - HMS Graph (http://uboatarchive.net/U-570BritishReport.htm):
Quote
  5.  In the case of the Junker's air compressor exhaust valve, the valve floats on the end of the main spindle.  It is rotated by an extension from the valve passing down the centre of the main spindle and is turned by hand.


(http://img848.imageshack.us/img848/8903/gerat2.jpg)


So I guess, the hand wheel is the part of the valve and the red bar handle is the part of the grinding gear, right?


--
Thanks, regards

Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2012, 09:57
Yes Maciek
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2012, 06:15
I have with pleasure noticed there are still modellers who start building various versions of the VIICs and seeing the results I`m impressed with the skill and patience they put into the work. However it strikes me that a lot of effort is put into the canning and wheathering and some of the models look to me a bit overdone. The average lifetime for a VIIc during the war was relatively short and the pressurehull didn`t have much visible canning nor corrosion as on present days  U- 995 more than 60 years old. There could be a little canning on the casing, but to my opinion not always very visible. As an example I`m posting  pictures of different stages in the life of  U-995. 1. At the end of the war 1945 being 2 years old, 1953 KNM Kaura ex U-995 after 8 months  in service, 1954  showing KNM Kaura ex U-995 in drydock  being 11 years old and just after 12 months autum- and winterservice in the hostile waters above the artic circle, and 1972 U-995 just in place at the war memorial at Laboe, Kiel.  As you may be able to see it is very little canning and moderate weathering (1954 drydock) in spite of the though service she had. The welding seams and the casing rivets are also bearly visible. A few VIICs could be pretty weatherbeaten no doubt, but in general they did`t look like Das Boot in the movie. So if you want to give an authetic view of a VIIC show a bit moderation in emphasising on the weathering, canning, weldingseams and rivets even if it`s great fun doing it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 19 May , 2012, 18:06
Hi Tore,

Good advice I think! And the rest of what follows of mine means little because you are a vet and were there! I'm just an armchair historian! But it might have some small use...

That 3rd shot shows the perfect amount of canning in my opinion...My experience is that any sheet metal on ribs will have some dish/can effect because of imperfect materials, expansion/contraction, etc. I've seen the QEII and almost any ship - well, whatever the name or effect, overall you can easily tell sheets of metal are affixed to ribs, because you can see subtle differences where the ribs are and are not.  think it's important to communicate that, otherwise a model can look like a solid piece of plastic.

Weathering - I forget if it was Eugene Fluckey or Richard O'Kane, but one of them was walking back to their USN Gato at Midway, and almost didn't recognize her: because they obviously never got an overall view while at sea, but at the pier the hull, originally all black and clean, was faded to many grays and charcoals, and had chipping and salt spray weathering all over, looking rather old and tired after only 6-8 weeks at sea. In Iron Coffins the same thing happened to Werner, although with his patrol history not quite matching records, maybe he was being dramatic!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2012, 00:22
Wink
 If you have driven a car for 60 years doesn`t mean you know all about driving and I for sure make mistakes and have failing memories (I`m going on 84). You are rigth about the canning can be caused by expansion /contraction sometimes due to welding. Many new ships have very visible canning on their deliveryday.( on the U 995 picture below you see the result of a brand new welding which never have been at sea). On naval vessels particulary destroyers and frigates this is sometimes very visible. On submarines, anyhow german and british built, you are sometimes able to see canning on the ligth casing, but very seldom on the pressurehull. The VIICs had a very ligth and susceptible casingconstruction and we had dammages to the casing. I particulary remember we crossed the North Sea in the month of November for noisetrials in Scotland and we had a terrible weather, 1/3 of the casing was smashed by the sea and we came in almost like a tube. On the Laboe U 995 you see some dents and canning,  particulary on the new plating which they have welded and not rivited. Some other indentions are due to old minor collision dammages. I am posting a few picture below to explain what I mean.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2012, 01:54
As a follow up on my theory on submarine canning/ indents, I`m posting a picture of a naval surfacevessel which shows how it might be in some cases on surfaceships.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 22 May , 2012, 02:43
You're a treasure and we hope to have for for 84 more years!

That shot of 995 was very angular, perhaps a new word is needed to be accurate: it's not really canning in that shot, but does show ribs...maybe: "ribbing"???

Something to show it's not a plastic hull.

I imagine surface ships, especially that frigate with the V, would get a a lot of wave slapping, too.

Thanks for the pix and the discussion starter!

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 May , 2012, 14:55
Tore, did you take this picture while on KNM Kaura?  I am trying to figure out the date of the picture, as you can clearly see the colour coding on the piping :-)

(http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=2459;image)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2012, 23:14
Simon
This picture is not from my time onboard I guess it is from 1970- 1972 just after the germans had (carefully) restaured the U 995  for the first time. I have been looking at my pictures and cannot se the paintings (very bad quality). As told previously we didn`t use the coding very much. My idea is that the whole design of the german sub is based on the possibility that it should be able to be handled by relatively poor trained crew compared to the the UK and US crew. We had very experienced crew recruited from our fairly large merchant marine thus we didn`t use the colourcoding, today it is used all over.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 May , 2012, 23:26
Simon
Looking at your last post, I wasn`t sure you got my idea about the governor servomotor oilpipes OK so I post a couple of pictures marking off the pipes. Both pipes, not three, are bundled together as shown and goes aft along the roots blowercasing (fixed to that) to about middle of the housing (sorry no picture) then goes down and disappear under the floor where the return (blue) joins the main engine returnoilpipe. The luboilpressurepipe I believe goes under the floor up front to the branch off  just after the luboilcooler marked red on the systemsketch. The returnpipes are marked blue.
Tore

(http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=2477;image)


Tore, do you remember how the red line would run forward or have a suggestion on how it return?

Would it return just under the floor deck (green arrow) or would it be lower down like near the top of the oil ranks (blue arrow)? Any help would be grateful as I would like to add it to the drawing

(http://img217.imageshack.us/img217/4313/new1qm.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 May , 2012, 23:28
Simon
This picture is not from my time onboard I guess it is from 1970- 1972 just after the germans had (carefully) restaured the U 995  for the first time. I have been looking at my pictures and cannot se the paintings (very bad quality). As told previously we didn`t use the coding very much. My idea is that the whole design of the german sub is based on the possibility that it should be able to be handled by relatively poor trained crew compared to the the UK and US crew. We had very experienced crew recruited from our fairly large merchant marine thus we didn`t use the colourcoding, today it is used all over.
Tore

Thanks Tore!

My idea is that the whole design of the german sub is based on the possibility that it should be able to be handled by relatively poor trained crew compared to the the UK and US crew

A very war-time thing to do I imagine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2012, 23:58
Simon
I discovered another detail which perhaps support my theory. On the first restaurationpicture they have fitted, what I presume is a startinginstruction plate we didn`t have such, that would have been an insult to the engineers. On later picture of the Laboe U 995 these plates are gone, souvenier hunters? I am posting two pictures showing this plea excuse the terrible quality of the photo from my time, but I didn`t any other.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 00:21
Supplypipe to governor servomotor.
I cannot for 100% sure remember where the supplypipe was placed under the deckplating. I don`t think it was fitted as your red arrow points out, that would be in conflict with the crankcasedoors, more as pointed out by the blue arrow may be  a bit higher. The return pipe (blue) connects with returnpipe from the supercharger and then the distributionvalvechest. The returnpipe from the supercharger seem to have an unusual bend (rigth were the red clutchwheel is). Your drawing is as usual a pleasure to look at
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 00:57
I have tried to indicate the supply  (red) pipe and returnpipe (blue) on your drawing. all the blue lines merge and end up in the valvechest, which can`t be seen on this drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 01:08
Sorry Simon I posted the wrong picture, it`s corrected now.
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 May , 2012, 01:45
Tore, is this the oil cooler (red arrow)?

(http://img407.imageshack.us/img407/6348/new2a.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 01:48
I have the feeling a further detail of the luboilsystem is probably required. I`m posting a picture of the port system where I have coulored the returnpipes blue and pressurepipes red.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 May , 2012, 02:09
Tore, I just noted a charge between U-995 and the plans with the pipe under the super charger. On the plans it layout this like in red, but in real life it like in the drawing & picture. Do you think there a reason they change the layout? Maybe they change the layout to get around the clutch.

Also, should I have the wheel in red, or should it be unpainted?

(http://img853.imageshack.us/img853/8924/new3sp.jpg)

(http://img96.imageshack.us/img96/9422/new4a.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 May , 2012, 02:10
I have the feeling a further detail of the luboilsystem is probably required. I`m posting a picture of the port system where I have coulored the returnpipes blue and pressurepipes red.
Tore

Thanks a lot! This help me understand  :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2012, 02:26
Hi Simon
Also, should I have the wheel in red, orshould it be unpainted?


Take a look here:
(http://uboatarchive.net/U-570Photo28.jpg)


It looks like it was painted with black.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 May , 2012, 02:42
Thanks Maciek

Maciek, this the red arrow in post #295 the oil cooler?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 04:15
It was for sure not red, black is very probable, I would have preferred unpainted but I really don`t remember.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 05:07
Luboil cooler.
Its a bit hard to say it looks a bit small. I guess we have to figure the pipelineconnections. You should have seawater inlet and outlet, main luboil pipe from oilpump pipe chest to coolerinlet and main luboil pipe cooled oilpipe out to a 3 way cock and a branch off to the governor servomotor. Then a smallby pass pipe luboil out next to the inlet and return to the systemtank. That makes 5 pipeconnections directly on the coolerhousing. On your drawing I recognize two, but the placing and the tubular look certainly could illustrate the luboilcooler when the piping is upgraded.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2012, 06:58
Tore, I just noted a charge between U-995 and the plans with the pipe under the super charger. On the plans it layout this like in red, but in real life it like in the drawing & picture. Do you think there a reason they change the layout? May be they change the layout to get around the clutch.

Also, should I have the wheel in red, or should it be unpainted?

(http://img853.imageshack.us/img853/8924/new3sp.jpg)

(http://img96.imageshack.us/img96/9422/new4a.jpg)

Having a closer look at the supply/returnpipes I believe there is indeed a bend in the return pipe,but I believe it migth be only to follow the Roots blower gearcasing. I cannot see the reason for an alongship bend.the supplypipe seem to be running straigth
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 May , 2012, 19:16
Tore, how was the floor plating supported between the two engines?

Was it supported directly to the engines (fig. 1) or was it supported by a number of legs from the top of the oil tanks and was not attach to the engine in any way (fig. 2).

(http://img528.imageshack.us/img528/1107/floor1.jpg)
Figure 1.

(http://img801.imageshack.us/img801/4532/floor2v.jpg)
Figure 2.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 May , 2012, 00:34
Simon
I cannot remember for 100% sure, but if you look at the drawing of the GW engine below I have indicated the floor approximately by a green line. The crankcasedoors are marked as well. You wouldn`t fix anything permanently to the engine block (crankcase) which obstruct the crankcase access. I believe in fact that any floorsupports would not be fitted on the engine above the foundation, the floorplates had to be easy to remove. Your fig. 2 could be an alternative, but I would guess the supports would possibly go down to the foundation area and the bar alongside the engine would be in bolted sections not fixed to the engine above the foundation. This is for the GW engines and an assumption from my side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 May , 2012, 03:51
Hi Simon
Maciek, this the red arrow in post #295 the oil cooler?


Well, I guess so.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 May , 2012, 09:21
Floorplating engineroom.
To follow up my theory and better than an old mans memory, I post a picture which I believe shows that there are no contacts with the floorplatings (supports) and the main engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 May , 2012, 09:39
Luboilcooler.
I can confirm the that the shown item is the luboilcooler, even if the Uboat historia tells it`s a filter. However I think it would be an advantage to have a closer look at the pipings. Below I have indicated  (green) a bit simplified the seacooling waterpipes. Together with the previous posted luboilpipes (connections) it migth be possible to figure out how the hook up is. The seacoolingwater chest have 5 valves and is situated towards the fwd enginroombulkhead I believe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 May , 2012, 14:59
Floorplating engineroom.
To follow up my theory and better than an old mans memory, I post a picture which I believe shows that there are no contacts with the floorplatings (supports) and the main engines.
Tore

I also believe there no contacts with the floorplatings (supports) and the main engines, as if there was a slight different in frequency between the engines, the floorplatings would rattle itself to died.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 May , 2012, 15:31
Luboilcooler.
I can confirm the that the shown item is the luboilcooler, even if the Uboat historia tells it`s a filter. However I think it would be an advantage to have a closer look at the pipings. Below I have indicated  (green) a bit simplified the seacooling waterpipes. Together with the previous posted luboilpipes (connections) it migth be possible to figure out how the hook up is. The seacoolingwater chest have 5 valves and is situated towards the fwd enginroombulkhead I believe.
Tore

Hi Tore

I feel that the seacoolingwater chest (5 valves) was location fwd enginroombulkhead and on the starborad side of the boat. I also believe this is picture below (#2)
(http://www.u-historia.com/uhistoria/tecnico/visitaguiada/diesel/valvulasfiltro.jpg)

Tore, could this be the sea water inlet valve (Below # 13 & 14)
(http://www.u-historia.com/uhistoria/tecnico/visitaguiada/diesel/detallebombaemergenciaaceite.jpg)
Picture from http://www.u-historia.com/ (http://www.u-historia.com/)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 May , 2012, 19:00
Luboilcooler.
I can confirm the that the shown item is the luboilcooler, even if the Uboat historia tells it`s a filter. However I think it would be an advantage to have a closer look at the pipings. Below I have indicated  (green) a bit simplified the seacooling waterpipes. Together with the previous posted luboilpipes (connections) it migth be possible to figure out how the hook up is. The seacoolingwater chest have 5 valves and is situated towards the fwd enginroombulkhead I believe.
Tore

Thanks, Tore for the information.

Here the layout in real life between the Cooler and 5 valves.

(http://img684.imageshack.us/img684/6944/new1ha.jpg)
(http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=2694;image)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 00:14
Simon
The valvechest shown is indeed the seawater chest and has branch off to stb and port luboilcooler. I am posting a brushed up version of the seawater coolingsystem.
The blue line is the suction from sea. First the conventional hull seavalve (seen on your U historia picture 13) same has an air blow connection for seaweedcleaning, then as always on the seavalves, a second valve  (sluicevalve to be shut for depthcharges) also seen on your picture, 14, and a filter. The pipes ends up at the engine attached pistonpump  fwd end of engine.
Then the colour changes to green(pressureside) passes an airvessel ( to compensate for the pistonpump pressurevariations) and continues as previously explained.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 00:20
Floorplating engineroom.
To follow up my theory and better than an old mans memory, I post a picture which I believe shows that there are no contacts with the floorplatings (supports) and the main engines.
Tore

I also believe there no contacts with the floorplatings (supports) and the main engines, as if there was a slight different in frequency between the engines, the floorplatings would rattle itself to died.
Simon.
You have a point there.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 00:40
Thanks Tore.

What is a "Air vessel"? What does it do?

This the "CW Pump" atteched to the engine? I been looking for it all day and can not find them.

Here the layout so far  :)
(http://img710.imageshack.us/img710/1356/new1qz.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 00:58
An airvessel ( sometimes called windvessel) is only a " bulb" rigth after a pistonpump. It contains an air cushion which act like a buffer and equalizes the pressure fluctuations coming from a reciprocating machinery like a pistonpump. Nothing much, just a casted "blimp" migth be an airconnection on the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 01:20
Coolingwater pump.
The seacooling waterpump as far as I remember was placed fwd at the engine on port engine stb side fairly low down. On the posted picture I have indicated what I think is the pump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 01:34
Coolingwater pump.
The seacooling waterpump as far as I remember was placed fwd at the engine on port engine stb side fairly low down. On the posted picture I have indicated what I think is the pump.
Tore

A big thanks Tore! I been looking for it all day, never thought it been could be on the engine  :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 01:40
Seawaterchest.
Your nice drawing of the chest was in the beginning a bit confusing to me, it looked like the stb engine was connected directly to port and that port ended nowhere. Is it by any means you are able to make it clear that they are connected to two different outlets of the chest?
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 02:15
Tore, hope this makes it a little clear to understand. I think I now know that you are talking about, I just realise the Purple & Green lines on my drawing are the wrong way around  :( I will fix this tomorrow.

(http://img27.imageshack.us/img27/1160/new3vg.jpg)

(http://img818.imageshack.us/img818/4718/new4y.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 02:33
Coolingwater pump.
The seacooling waterpump as far as I remember was placed fwd at the engine on port engine stb side fairly low down. On the posted picture I have indicated what I think is the pump.
Tore

Tore I also just found this  :)

Quote
U-Boat Type VIIC Manual - Page 120

Cooling water pump

The cooling water for cooling the engine lubricating oil cooler, the cylinder barrels, cylinder heads, exhaust valves and exhaust manifolds is fed by a double-piston pump. The drive of the pump takes place via the crank, which is propelled by gear wheel transmission from the crankshaft (Ratio 2:1).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 02:41
Here the correct layout. Could not wait till morning. Would hate to see U-1308 go to sea with bad piping ;D

(http://img441.imageshack.us/img441/43/new3c.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 07:17
Good thing you are at sleep.
The  redchecked pipe on your drawing is the seawater crossoverline, it ends on both sides in the same way, I believe you have indicated stb only. So may be you should add the two valves after the filter on port as well. You could perhaps add the standard weed airblow cleaning (both sides). From the seawater crossoverline are the suction side connection to both pistonpumps on the engines, and on stb side the the suction on electric driven ciculationpump, and handpump, see the posted picture marked green. I believe there is a mistake in the system drawing indicating no suctionconnection to the stb enginepump from the crossover.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 08:31
Luboil cooler seawaterpiping.
The pipes from the engine pumps goes to the valvechest ( there are two more pipes as well, forget about them now) and are distributed via your green and violet lines to the luboilcoolers. enters the luboilcoolers via a selectorvalve which means it can either enter the cooler or bypass it. Normal position is enter and the inlet connection to the outlet is shut. Hence it goes via the coolers and cools the oil before it goes to the engines a little heated  in order to prevent a coldshock to the engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 13:43
Luboilcooler 2
As far as I can see the luboilcooler bypass pipe seems to be without contact with the selectorvalve but disappear into the housing, is it any reason for that, I should believe it would be more like the red pipe indicated on the posted picture , you have in fact indicated the same by blue overunning the pipe. On my posted picture I have indicated on the crossover line where I believe the suctionconnections to the various pumps are.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 May , 2012, 14:52
Luboilcooler 2
As far as I can see the luboilcooler bypass pipe seems to be without contact with the selectorvalve but disappear into the housing, is any reason for that, I should believe it would be more like the red pipe indicated on the posted picture , you have in fact indicated the same by blue overunning the pipe. On my posted picture I have indicated on the crossover line where I believe the suctionconnections to the various pumps are.
Tore

* Tore, Thanks for all the information!!!! :) It mean a lot that you are willing to help. They perhaps are little detail,  but to me, knowing that they were wrong would drive me mad!

* Yes, you are right about the luboilcooler bypass pipe seems to be without contact with the selectorvalve. I misread the system drawing yesterday, will fix this today :)

* Also really happy that you think the system drawing is wrong about indicating no suctionconnection to the stb enginepump from the crossover. Yesterday I spend about 8 hours looking at that system drawing trying to workout why the German Engineers had made no connection to the stb engine pump ???

* I will also do the miss port side sea inlet valve today. As a little tried last night to finish the drawing.

Low Pressure "weed airblow cleaning"

I was able to find the system drawing for this :) Also from the picture below, there look like two positions where the low pressure air entered the sea valve, this is correct?

Maciek, do you know this section of the Low Pressure system?


(http://img513.imageshack.us/img513/3023/new1ql.jpg)

(http://img684.imageshack.us/img684/5827/new4zt.jpg)



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 15:16
I would believe the violet LP pipes are the rigth ones. You are awake and up, I am about to hit the sack in a heatwave 28 degrees C. All the snow is melting in the mountains which means the annual springflood is on its way, nothing serious though. Good luck with your work looking forward to see the results tomorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2012, 23:56
Seaweedcleaning.
I`m not sure if I misunderstood you. I think the the boardvalve (outer) opens  inward. In the event that seaweed obstruct the intake, the second valve (sluicevalve) is shut and LP air valve is opened allowing the air to the space between the sea and sluicevalve thereby blowing  the weed out. I don`t think there is any airconnection to the sluicevalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2012, 06:49
Luboilreturnpipes.
I have been looking a bit more on the subject, see picture below. I think the strange bends on you drawings migth come from the relatively large returnpipe from the Roots blower (blue).The supplyline to the servomotor (green) is coming from underneath the deckplating and is fairly straigth. The servomotor returnpipe (yellow) is making a bend under the Roots blower casing for some reason unknown to me, but anyhow it has to connect to the larger pipe from the blower.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2012, 07:15
Airvessel
As it seems to be an unknown item, I guess a picture would help when you are drawing same. It is not the airvessel on the engine attached coolingwaterpump but the airvessel on the piston trimpump.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2012, 15:18
Hi Tore
I believe there is a mistake in the system drawingindicating no suctionconnection to the stb enginepump from the crossover.


You are right - on the original, german drawing it is drawn correct:
(http://uboatarchive.net/U-570Plate13.jpg)


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2012, 15:22
Hi Tore
I`m not sure if I misunderstood you. I think the the boardvalve (outer) opens  inward. In the event that seaweed obstruct the intake, the second valve (sluicevalve) is shut and LP air valve is opened allowing the air to the space between the sea and sluicevalve thereby blowing  the weed out. I don`t think there is any airconnection to the sluicevalve.


I guess, your explaination is also correct for my question asked some time ago:
Quote
I have got another question regarding to the low pressure air installation - I have noticed, that hull valve in the E-motor/Aft torpedo room (E-motor cooling water intake and torpedo compensating tanks flooding) has also connection to thelow pressure air installation. I wonder what is for - I guess it was used to "crack" the valve - to help opening valve at greater depth or with the jammed valve. Is that right?
http://models.rokket.biz/index.php?topic=121.msg10617#msg10617


It's great to get confirmation.


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2012, 15:25
Tore, back to the question about location of the cooling water pump in E-motor room:
I believe it`s fitted on port side rigth where the emergencysteering wheel is stowed. It`s a relatively small centrifugal circulation pump.


I found pictures which fit with your answer:
(http://u-historia.com/uhistoria/tecnico/visitaguiada/bombas/enfriadoresenpopa-1.jpg)
(http://u-historia.com/uhistoria/tecnico/visitaguiada/bombas/enfriadoresenpopa-2.jpg)
(source: u-historia.com)


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2012, 16:03
Hi Simon
Maciek, do you know this section of the Low Pressure system?
Not really. I also think, that there is no connection with the sluicevalve. I think that there is visible "main lp line", going through the diesel engine room, there is a branch to the hull valve blowing connections, then the valve (which does not fit), and above it the branches to the stb and port hull valve. There is also one line, which also does not fit. I will try to figure it out when I will get a while.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 May , 2012, 22:35
Luboilreturnpipes.
I have been looking a bit more on the subject, see picture below. I think the strange bends on you drawings migth come from the relatively large returnpipe from the Roots blower (blue).The supplyline to the servomotor (green) is coming from underneath the deckplating and is fairly straigth. The servomotor returnpipe (yellow) is making a bend under the Roots blower casing for some reason unknown to me, but anyhow it has to connect to the larger pipe from the blower.
Tore

Great picture! It conform a few things for me  :)

I had a good idea that the servomotor returnpipe (yellow) line bend under the Roots blower casing, but this picture conform it. It bend back so it can join the Roots blower (blue) line. I have a clear picture that show this. I have already update my drawing to show this.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 May , 2012, 22:37
Airvessel
As it seems to be an unknown item, I guess a picture would help when you are drawing same. It is not the airvessel on the engine attached coolingwaterpump but the airvessel on the piston trimpump.

Thanks for the picture. Very useful. Now I have a idea that to draw and look for  :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 May , 2012, 22:42
Hi Tore
I believe there is a mistake in the system drawingindicating no suctionconnection to the stb enginepump from the crossover.


You are right - on the original, german drawing it is drawn correct:
(http://uboatarchive.net/U-570Plate13.jpg)


--
Regards
Maciek

I am glad that both of you guys found this mistake :) Like I said before I spends a few hours trying to workout why the German Engineers had made no connection to the stb engine pump.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 May , 2012, 22:44
Hi Simon
Maciek, do you know this section of the Low Pressure system?
Not really. I also think, that there is no connection with the sluicevalve. I think that there is visible "main lp line", going through the diesel engine room, there is a branch to the hull valve blowing connections, then the valve (which does not fit), and above it the branches to the stb and port hull valve. There is also one line, which also does not fit. I will try to figure it out when I will get a while.


--
Regards
Maciek

Thanks  :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 May , 2012, 22:53
Hi Tore

I been away today and I am away tomorrow but I should have the new drawing ready in a few days.
 
I am really happy with the updated drawings as I have workout a few more pipes and corrected a few valves to there correct style :) I have found doing both (lateral and dorsal) views at the same time has help heaps to increase the accurate of the drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2012, 23:16
Maciek
I had forgotten your question about the seaweedblowing, good it popped up later. As a curiousium I can mention the arrangement is useful even today, not so much for seaweeds, but all the plastic floating around. A plastic sheet can very effectively block the seawater intake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2012, 23:42
Seaweed blowing
I realize this morning that my second reply yesterday on the subject for some reason was not posted. I am posting a picture where I have tried to figure out how it works. The biggest pipe, marked blue is the LP main supplypipe going all the way through the boat. The green line is the weedblowing branch off to a distribution valve. The yellow line is the supplyline which goes via the local seaweed blowingvalve and then to the board seavalve. This is an assumtion I don`t remember for sure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2012, 23:53
Hi Tore

I been away today and I am away tomorrow but I should have the new drawing ready in a few days.
 
I am really happy with the updated drawings as I have workout a few more pipes and corrected a few valves to there correct style :) I have found doing both (lateral and dorsal) views at the same time has help heaps to increase the accurate of the drawing.

I agree with you and are looking forward to seeing the drawing. I suppose you intend to brush up all the systems in the engineroom, that`s a vast task but very interesting. It`s just like beeing onboard again, we`ll get your U 1308 running properly in spite of wrong drawings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 May , 2012, 00:17
Hi Tore

I been away today and I am away tomorrow but I should have the new drawing ready in a few days.
 
I am really happy with the updated drawings as I have workout a few more pipes and corrected a few valves to there correct style :) I have found doing both (lateral and dorsal) views at the same time has help heaps to increase the accurate of the drawing.

I agree with you and are looking forward to seeing the drawing. I suppose you intend to brush up all the systems in the engineroom, that`s a vast task but very interesting. It`s just like beeing onboard again, we`ll get your U 1308 running properly in spite of wrong drawings.
Tore

I decide to put my other projects on hold for a while and review my engine room drawings for the few weeks before I start full time work in the snow, plus how often can you ask someone who been in a Type VIIC
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2012, 00:34
Simon
The idea of somebody on the same planet is just getting ready to work with the falling snow while for us mother nature is removing it quickly and put in flowers instead sounds crazy. I would rather be in a VIIC engineroom than the snow. The funny thing is I thougth I had forgotten everything, but it`s gradually coming back as I study the details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2012, 00:42
Tore, back to the question about location of the cooling water pump in E-motor room:
I believe it`s fitted on port side rigth where the emergencysteering wheel is stowed. It`s a relatively small centrifugal circulation pump.


I found pictures which fit with your answer:
(http://u-historia.com/uhistoria/tecnico/visitaguiada/bombas/enfriadoresenpopa-1.jpg)
(http://u-historia.com/uhistoria/tecnico/visitaguiada/bombas/enfriadoresenpopa-2.jpg)
(source: u-historia.com)


--
Thanks, regards
Maciek
Very good! Marko you can even see the top of the thrustbearing
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 May , 2012, 03:17
Simon
The idea of somebody on the same planet is just getting ready to work with the falling snow while for us mother nature is removing it quickly and put in flowers instead sounds crazy. I would rather be in a VIIC engineroom than the snow. The funny thing is I thougth I had forgotten everything, but it`s gradually coming back as I study the details.
Tore

What seen funny to me this...

The time "you" spend at sea would be equal to the time I have been forecasting avalanches & and the time "I" have been at sea equal to the time you have been chasing avalanche :-D

Number of days at sea: About 7 days.
Number of days in the snow: 22 years forecasting avalanche danger ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 May , 2012, 03:44
Simon
The idea of somebody on the same planet is just getting ready to work with the falling snow while for us mother nature is removing it quickly and put in flowers instead sounds crazy. I would rather be in a VIIC engineroom than the snow. The funny thing is I thougth I had forgotten everything, but it`s gradually coming back as I study the details.
Tore

Here my engine room and some pictures of my at work ;D

(http://img703.imageshack.us/img703/6127/new1ak.jpg)
This is the view from the top of the mountain that I work at.

(http://img708.imageshack.us/img708/5207/simonandreabomb.jpg)
We used a lot of explosives to control the avalanches. Here me (left) teaching a younger ski patroller what to do.

(http://img94.imageshack.us/img94/8563/stuckg.jpg)
Here my outside, making sure that is safe to clear the road. There is already over 3m of avalanche debris on the road.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2012, 05:01
Simon
Meaningful job you have. Even if we were running a submarine we were skiing a lot, the snow was rigth down to the sealevel as can be seen on the posted picture. We usually borrowed skis from a local armycamp and spent hours in the snow,  you could enjoy skiing till end june up north. Your mountains seems to be much like ours up north and northwest of our country. Our people doing the same job as yours had a busy time this winter as we had one of the worst avalance winter ever.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2012, 12:07
Maciek
 I think I remember you mentioned earlier that you are planning to visit the Laboe U 995 this summer or autumn. I guess you are making a list of what details you shall be studying and I presume you take a camera along. I have never visited her in her present state allthough passing the Denkmal many times by ship. Before you go, may be you`d be interested in the story how she actually ended on concrete supports at Laboe. KNM Kaura  ex U-995 was in active service in the Royal Norwegian Navy from December 1952 till December 1965. The latter part of her lifetime she was a "schoolboat". The first years, when I was on board she was a" frontline boat" and the CO, No 1 and me became very good friends who met after our service onboard occasionally to memorize old days. The CO has now passed away, but he mention a few interesting things on our social meetings.
After his time onboard, he became in the 1960 years  in charge of a newbuilding programme for the Norwegian navys new subs in Germany. During these years he came in contact with a number of german ex Ubootofficers, himshelf beeing a navyofficer with war experience on the allied side, had a few problems in the beginning but in the end he became friends with quite a few german officiers. I think he was even in a party with admiral D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 May , 2012, 14:46
Hi Tore

Great story!!

I was wondering do you have any pictures of the piping under the flooring of the engine room?

I can not imagine there a lot of space under the flooring with all the different piping system, especially not like you see in the Das Boot movie!  I have workout the easy piping, but there still big sections missings :( So I have started mapping the paths of the other piping systems, to help me fall in the missing sections of piping. I can not believe the German
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 May , 2012, 15:32
Plate 14:  (Left) Engine lubricating oil system, (Right) lubricating oil storage, sump and purifying system, for Krupp engines

(http://img442.imageshack.us/img442/5314/new2su.jpg)
Q: Do you remember where the two pumps for cleaning are?


(http://img17.imageshack.us/img17/6656/new3os.jpg)
Q: The system drawing show two 3-ways valve, is this a error? Why would you need a 3-ways valve; a check valve should be Ok here or am I missing something.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2012, 22:46
Hi Tore

Great story!!

I was wondering do you have any pictures of the piping under the flooring of the engine room?

I can not imagine there a lot of space under the flooring with all the different piping system, especially not like you see in the Das Boot movie!  I have workout the easy piping, but there still big sections missings :( So I have started mapping the paths of the other piping systems, to help me fall in the missing sections of piping. I can not believe the German
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2012, 23:16
Luboil checkvalves.
The footvalves at the luboilsuction is a checkvalve, the symbol is round, a 3way cock is square. Se drawing below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2012, 23:44
Lub oil puryfier pumps.
As far as I remember the suction- (dirty oil) and deliverypumps( clean oil) were intergrated in the puryfier as was the case of the heater. Unfortunately I don`t have a picture of the purifier but I`ll look for it and revert.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 May , 2012, 23:44
Luboil checkvalves.
The footvalves at the luboilsuction is a checkvalve, the symbol is round, a 3way cock is square. Se drawing below.

The valve icon has three lines on it, so does this mean OFF/HALF/FULL?

(http://img833.imageshack.us/img833/4030/new2sg.jpg)

Also below if you look at the lines for the dirty lubricating oil from the manifold (M4) to the tanks there are check valves for each line. But there no check valve for the clean lubricating oil from the manifold (M3) to the tanks. Tore, do you think this is a error or are they not needed?

(http://img442.imageshack.us/img442/5314/new2su.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2012, 23:56
Luboil checkvalves.
The footvalves at the luboilsuction is a checkvalve, the symbol is round, a 3way cock is square. Se drawing below.

The valve icon has three lines on it, so does this mean OFF/HALF/FULL?

(http://img833.imageshack.us/img833/4030/new2sg.jpg)

Also below if you look at the lines for the dirty lubricating oil from the manifold (M4) to the tanks there are check valves for each line. But there no check valve for the clean lubricating oil from the manifold (M3) to the tanks. Tore, do you think this is a error or are they not needed?

(http://img442.imageshack.us/img442/5314/new2su.jpg)
Simon
 I have the answer but my internet connection is shutting down I revert this afternoon.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 10:17
Back on the net again.
The separators dirtyoilpump sucks from the systemoil tanks, hence checkvalves and strainers, and the pressureside (black) of the pump deliver via the heater the dirty oil to the sentrifuge where it`s cleaned and the separator clean oil pump sucks the clean oil from the sentrifuge and delivers back to the systemtank, hence no checkvalves on the deliverypipes from the cleanoilpump. Remember the icon for the pumps has always blackcoloured pressureside. The systemsketch is OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 10:25
The valveicon having 3 crosstripes is a puzzle to me and I guess you shall find very few in the system, I think there are two in the emergency luboilpump suction, (when the fueltransferpump is used as a lubeoilpump)  for port and stb systemluboil tank where you want to be sure there are no contamination of fuel and lubeoil and then I guess one on  the big trimpump in the controlroom. Might be something pops up later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 12:37
Luboilseparators
I have tried to look for a picture of the lubeoil separator (centrifuge) but sorry I didn`t find any. I think it was the Westfalia make.The only picture I got hold of was the present days Westfalia lubeoilseparators, allthough basically the same system it is not 100% the way it looked. Migth be somebody have a picture?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 May , 2012, 13:35
Thanks!  :) :)

Tore, do you per-heat the dirty oil to help clean the oil?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 13:55
Yes you both heat and add water to "wash" the oil in the separator.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 May , 2012, 14:02
Yes you both heat and add water to "wash" the oil.
Tore

Water :o

I imagine fresh water? Could the water be reused for more clearing or was it only used once?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 14:08
No if you look at the coolingwatersystem there is a branch off to the separator.Don`t forget it is a centrifuge and it get rid of the water with impuritites.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 14:24
Have a look at the seacoolingwatersystem below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 May , 2012, 14:48
(http://img17.imageshack.us/img17/6656/new3os.jpg)

Tore, what this the different between a straight-way valve and a check valve non-adjustable (A)?  (E.g. Between Port LO tank and LO pump)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 23:03
I`m not sure if I understand you correct, but a non adjustable checkvalve is a non return "footvalve" built into the pipeline with no possibility to regulate from outside. It is usually fitted at the end of a suctionline to maintain the liquidcolumn to a pump so you don`t have to prime ( get rid of the air) the line every time the pump starts. You can also have an adjustable checkvalve which means you can open it by a hand. A straigth-way valve is to me an ordinary  throughflowvalve. may I ask in which connection have you seen a " straigth-way" valve? perhaps I can give a better explaination.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2012, 23:31
Simon
I had a look at the english translation of the german iconexplaination. I think I know what you mean. The translator used an unusual word "valve" for the german "hahne" which means cock.
The icon used is a straigth throughflow cock, which means it has a simplifed casing and a removable handle, not wheel (see picture) and the meaning of straigth is that it is either shut or opened by hand, It is used for double sealing of the pipe, the check valve shut by itshelf.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jun , 2012, 01:14
Simon
I had a look at the english translation of the german iconexplaination. I think I know what you mean. The translator used an unusual word "valve" for the german "hahne" which means cock.
The icon used is a straigth throughflow cock, which means it has a simplifed casing and a removable handle, not wheel (see picture) and the meaning of straigth is that it is either shut or opened by hand, It is used for double sealing of the pipe, the check valve shut by itshelf.
Tore

Tore, if the handle was removable, would it be keep on the valve, or were they usually keep somewhere other?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2012, 10:06
On essential cocks seldom used, like luboilsuction shut off you would`t keep it on but store it maybe in brackets on the bulkhead. The reason for that is you would prevent somebody to shut it accidentially. If the cocks were way under the floorplates sometimes you could use a long T piece instead of the handle. I wonder if the stripe drawn out from the icon could symbolize that, nothing mentioned about this on  the plate. Otherwise the handle was pretty much  as seen on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jun , 2012, 19:14
U-boat Pumping 101 ;D

(http://img841.imageshack.us/img841/826/system1o.jpg)
(http://img853.imageshack.us/img853/1991/system2g.jpg)
(http://img259.imageshack.us/img259/7762/system3.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jun , 2012, 19:52
U-boat Pumping 102

(http://img824.imageshack.us/img824/7983/pipe3t.jpg)
(http://img9.imageshack.us/img9/6498/pipe2fq.jpg)
(http://img233.imageshack.us/img233/1289/pipe1f.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jun , 2012, 20:02
Hi Tore

Still working on the other piping, but from below you are see is starting to look good  :)

(http://img710.imageshack.us/img710/7105/allpipings.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2012, 23:48
Simon
 As always a pleasure to look at your drawings.We should had you around when we were training our crew.  As far as I can see everything seems to be correct I shall have a closer check this week end, looking forward to seeing the rest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 08:47
Dirty oil handpump system.
I realize you are not finished with the drawing, but to me it seems that the suctionline from starboard systemtank lead to a different 3 waycock than port and you have 3 cocks on top of each other in the system.
I believe it is one suctioncock (A) directly under the pump where both systemtanks suction pipes enters, out from that cock is the common suctionpipe to the handpump.
Out from the handpump is the deliverypipe going to another 3 way cock (B) situated directly underneath a  cock (C) which is not in the system. From cock B the dirty oil can either be directed to a hoseconnection or via a funnel to 2 destinations. Rigth under the funnel is a 3 way cock again (D) which have connections to the dirtyoiltank or the suction of the handpump. This makes it possible either to pump  dirty oil from either of the system tanks to the dirtyoiltank or shut the funnelconnection and open a connection to the handpumpsuctionline so you can empty the dirtyoiltank by the handpump via the hoseconnection. This seems to be a little complicated without a drawing, and it`s of course difficult see everything on an unfinished drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 14:12
I have tried to fiddle with you nice drawing  in order to have an additional explaination. I`m not sure if it is of any help though.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jun , 2012, 15:00
From the picture below I believe that valve E this right above valve F and the hand pump is port of the these two valves. I am not 100% sure where valve C is  :(

Tore, the small air lines which go to the 3-way valve (with the red handle) do you know which system this is? Is it the Oxygen system, Engine starting air system or the low pressure system?

(http://img864.imageshack.us/img864/5407/p1100209.jpg)

(http://img690.imageshack.us/img690/7755/new1ik.jpg)

(http://img259.imageshack.us/img259/7762/system3.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jun , 2012, 15:04
I just realise I have one too many valves :o I will delete this now.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jun , 2012, 15:19
Updated drawing - I was just toll off by the U-1308 dock forman for installing incorrect piping into U-1308  ;)

Still looking for a home for valve C :(

(http://img171.imageshack.us/img171/7452/new2yg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 15:44
I cannnot remember what system the upper cock belongs to, may be if we can see something further up we should be able to figure out. The inlet pipe to the pump is in the bottom. May be you get the idea from the picture below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 15:53
OK
I`m hitting the sack if it`s still unclear I`ll make a drawing tomorrow morning.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 02 Jun , 2012, 18:52
I think you guys could build a 1:1 boat with the plans and images and knowledge you have! If only you had 3-5 million dollars in 1940s currency and a shipyard!

There's an Australian Billionaire who has serious plans to build a Titanic II cruise liner (I'm assuming the water-tight dors would go all the way to the deck above, this time!), maybe you could convince him or his mates to finance a VIIC-II.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 22:39
How about buying back the U 995 for 1,- D mark and bring it back to the true original shape.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 23:11
 Dirty luboil handpump
Here is a rough pencilsketch of the arrangement. C is omitted because it doesn`t belongs to the system. As you see cock A is fitted directly under the pump inlet which is 180 degrees to the outlet. It`s an ordinary vane pump having inlet and outlet opposite each other.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2012, 23:48
Her is how the hand vane- wingpump looked like when new, that explains probably more than words.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 00:20
Final fiddling with your pump picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 03:25
And trying to adapt your fine drawing to the above system. Sorry for the bad quality of my scribling.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 06:29
The mysterious cock C.
 I have been pondering upon  this system and my best guess is the seacoolingwater drain and crossover for the main hullvalve for exhaust. You`ll see the system below as well as C cock pipes marked. I believe I can see the drainpipe ending in a funnel down in the bilgearea. We need to check the upper valves not seen on this photo to be sure. I don`t remember the system at all, so your guess is as good as mine and migth be better.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jun , 2012, 08:56
Hi Tore
An airvessel ( sometimes called windvessel) is only a " bulb" rigth after a pistonpump. It contains an air cushion which act like a buffer and equalizes the pressure fluctuations coming from a reciprocating machinery like a pistonpump. Nothing much, just a casted "blimp" migth be an airconnection on the top.
I have found the drawing of the cooling water pump for the G.W. diesel engine.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jun , 2012, 08:59
Hi Tore
I think I remember you mentioned earlier that you are planning to visit the Laboe U 995 this summer or autumn. I guess you are making a list of what details you shall be studying and I presume you take a camera along. I have never visited her in her present state allthough passing the Denkmal many times by ship. Before you go, may be you`d be interested in the story how she actually ended on concrete supports at Laboe. KNM Kaura  ex U-995 was in active service in the Royal Norwegian Navy from December 1952 till December 1965. The latter part of her lifetime she was a "schoolboat". The first years, when I was on board she was a" frontline boat" and the CO, No 1 and me became very good friends who met after our service onboard occasionally to memorize old days. The CO has now passed away, but he mention a few interesting things on our social meetings.

After his time onboard, he became in the 1960 years  in charge of a newbuilding programme for the Norwegian navys new subs in Germany. During these years he came in contact with a number of german ex Ubootofficers, himshelf beeing a navyofficer with war experience on the allied side, had a few problems in the beginning but in the end he became friends with quite a few german officiers. I think he was even in a party with admiral D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jun , 2012, 09:12
Hi Simon

Luboil checkvalves.
The footvalves at the luboilsuction is a checkvalve, the symbol is round, a 3way cock is square. Se drawing below.

The valve icon has three lines on it, so does this mean OFF/HALF/FULL?

(http://img833.imageshack.us/img833/4030/new2sg.jpg)
This translation of the OPZ Ventil is not quite correct. In the Technisches Hilfsbuch f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 10:49
Hi Tore
An airvessel ( sometimes called windvessel) is only a " bulb" rigth after a pistonpump. It contains an air cushion which act like a buffer and equalizes the pressure fluctuations coming from a reciprocating machinery like a pistonpump. Nothing much, just a casted "blimp" migth be an airconnection on the top.
I have found the drawing of the cooling water pump for the G.W. diesel engine.


--
Regards
Maciek
Exellent! Simon the bulb on the top is the airvessel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 11:08
Hi Simon

Luboil checkvalves.
The footvalves at the luboilsuction is a checkvalve, the symbol is round, a 3way cock is square. Se drawing below.

The valve icon has three lines on it, so does this mean OFF/HALF/FULL?

(http://img833.imageshack.us/img833/4030/new2sg.jpg)
This translation of the OPZ Ventil is not quite correct. In the Technisches Hilfsbuch f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2012, 23:17
From the picture below I believe that valve E this right above valve F and the hand pump is port of the these two valves. I am not 100% sure where valve C is  :(

Tore, the small air lines which go to the 3-way valve (with the red handle) do you know which system this is? Is it the Oxygen system, Engine starting air system or the low pressure system?

(http://img864.imageshack.us/img864/5407/p1100209.jpg)

(http://img690.imageshack.us/img690/7755/new1ik.jpg)

(http://img259.imageshack.us/img259/7762/system3.jpg)
Simon
I now realized I overlooked you question of the red handle, but I guess I answered same without refering to your question by my picture posted later. It is the pneumatic system for the main engine clutch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Jun , 2012, 00:09
Hi

Plate 14:  (Left) Engine lubricating oil system, (Right) lubricating oil storage, sump and purifying system, for Krupp engines

Q: Do you remember where the two pumps for cleaning are?
Lub oil puryfier pumps.
As far as I remember the suction- (dirty oil) and deliverypumps( clean oil) were intergrated in the puryfier as was the case of the heater. Unfortunately I don`t have a picture of the purifier but I`ll look for it and revert.


Tore, you remember well:


[quote author=U Bootskunde f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Jun , 2012, 00:24
Some more informations are provided here:
Quote from: Design Study of Former German Submarine  - Type IXC
[...]Filters, strainers, oil purifiers and oil coolers are similar to available U.S. commercial equipment. [...] The major differences from U.S. submarine practice are in the installation on the German vessels of a contaminated oil system, and the use of portable hose and interchangeable pipe connections to permit use of the hand and power driven detached pumps with fuel oil or other systems.
[...]
The forced lubrication system on the IX-C submarine is tied in with an oil purifying arrangement in a manner similar to U.S. submarine practice.  However, within both the lubrication and purifying systems, i.e: in tank design and in piping layouts, several basic and numerous minor differences exist.
[...]
The oil purifying system on the IX-C is of much lower capacity and is arranged to function in a somewhat different manner from the system as set up on U.S. submarines.  A single, standard DeLaval purifier, rated at 79.2 gals./hour is installed, while on U.S. vessels two 250-gals./hour purifiers are used.  The piping, pumps and heaters on the IX-C purifier system form an independent system and the units are selected with only that one service in mind, whereas the purifier pump and heater on U.S. vessels are of greater capacity than required for purification alone and are piped so as to be used also for transferring and heating oil from storage of sump tanks.  This dual service requires the installation of a "flow" regulating valve that isn't required with the IX-C arrangement.  A further difference exists in that the German purifier functions on a separator principle requiring a separate salt water feed line and salt water heater that need be kept in constant use and adjustment.  The Sharples purifier on U.S. vessels is presently used only as a clarifier and does not require a separate salt water feed line.  The German purifying arrangement with temperature and flow regulation on both the lub oil and salt water lines requires more attention during operation then on the U.S. setup with only temperature regulation on the lub oil line.
(http://uboatarchive.net/DesignStudiesTypeIXC.htm)


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Jun , 2012, 00:49
I have tried to look for a picture of the lubeoil separator (centrifuge) but sorry I didn`t find any. I think it was the Westfalia make.The only picture I got hold of was the present days Westfalia lubeoilseparators, allthough basically the same system it is not 100% the way it looked. Migth be somebody have a picture?
Quote from: British Report on U-570 - HMS Graph
Lubricating Oil Separator
Number:   149  Type 2 LHD 2/20
Capacity:   300 litres lub. oil/hour at 1 atm. at a speed of 1350/1,750 r.p.m. (66 galls./hr. at 15 lb./sq. in.).
Makers:   Ramesohl and Schmidt, Westfalia, Oelde.
Motor Makers:    Werdohler Pumpenfabrik, Werdohl, I/W Paul Hillebrand G.M.B
(http://www.uboatarchive.net/U-570BritishReport.htm)


I have no exact picture or photo, but I imagine, the purifer can look like in this US patent issued for Ramesohl and Schmidt A.G. in 1929.
http://www.freepatentsonline.com/1734533.pdf


And to compare - the lubricating oil system on the US submarines:
http://www.maritime.org/fleetsub/diesel/chap7.htm#7B


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2012, 11:12
Maciek
Interesting text and true the VIICs lubeoilseparator was a purifier and not clarifier which means to Simons astonishment that it was hooked up to the sea coolingwatersystem for washing the oil. I see in the paper that the make of the sentrifuge was DeLaval, I guess you probably had different makes. As far as I remember the main difference in look between DeLaval and Westfalia was the bowl. DeLaval have a domeshaped bowl whereas Westfalia was more pyramideshaped, I think Simon need primarely the shape and pipeconnection as everything else is intergrated inside the separator. I guess I would go for the Westfalia.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2012, 11:37
Lubeoil centrifuge.
A typical marine luboil centrifuge looks like on the posted picture, but again it is not excactly the one on a VIIC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Jun , 2012, 14:10
Tore
A typical marine luboil centrifuge looks like on the posted picture, but again it is not excactly the one on a VIIC.


Nice picture. I imagine that purifier on the type VIIC would like similar, except the driving motor would be mounted above the drum, with its shaft vertical, directly coupled with the rotating drum (and dirty and clean lubricating oil pumps).
I have noticed, that almost all the machines (main drain pump, trim pump in the control room, auxilary cooling water pump and auxilary lubricating oil pump in the diesel engine room, cooling water pump in the E-motor room) on the U-995 have such construction - vertical shaft driven by the electric motor mounted above. I think, that purpose was to better protection from water (besides the splash-proof or even water-proof cover).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2012, 14:25
Maciek that could very well be so, the problem would be you have lift the bowel up for cleaning and the water inlet would be on the top of the bowel see picture of the Westfalia purifier below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2012, 23:30
Maciek
Your remark that  in general the electric motor is placed vertically above machines particulary pumps, is of course correct and the reason you assumed, to prevent leakages down to the motor is rigth. However there are exceptions as for the aux. lubeoilpump, where the pump and motor are mounted horizontally on a common bedplate. The present days Westfalia lubeoil purifier has the motor horizontally and the purifier vertically mounted on a common bedplate. I simply cannot remember the execution of the VIIC purifier, if it was fitted for space reason vertically, I would imagine the emotor had to be underneath which is as you pointed out a bad solution, but not impossible, but I`ll give the present days Westfalia execution a 65% chance. Let`s see if somebody can dig up a correct picture
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Jun , 2012, 00:08
Hi Tore
Your remark that  in general the electric motor is placed vertically above machines particulary pumps, is of course correct and the reason you assumed, to prevent leakages down to the motor is rigth. However there are exceptions as for the aux. lubeoilpump, where the pump and motor are mounted horizontally on a common bedplate.


Do you mean this pump?
(http://u-historia.com/uhistoria/tecnico/visitaguiada/bombas/reservadeaceitelubricante.jpg)
(u-historia.com)


I have also noticed, that this pump is different. But:
[quote author="U Bootskunde f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 11:12
Generally speaking, any rotating machine resting on a single set of bearings will be more quiet than the same machine resting horizontally on two or more bearing races... Perhaps the vertical design was to aid in silent running?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 11:13
Maciek
You are absolutely rigth and the horizontal pump has nothing to do with aux. luboilpump. I was too quick in getting my mail posted before my internet connection was cut so I didn`t check properly. Sorry it is all wrong from my side.
So what is this horisontal centrifugalpump doing? It is not included in  any luboil-, fuelsystem as well as seacoolingwatersystem. If you look at the electric connectionbox it is not the normal german wartime type, I believe they were square, it looks more like a norwegian type of box after the war. The valve wheel is the shape of the potable freshwatersystem and there is a filter on the suction side. My guess is that the pump has been installed after my time by somebody who got tired of pumping freshwater by hand.Both the freshwatertank and the users are rigth behind the forward bulkhead. What do you think?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 11:43
Christopher.
Interesting aspect. I wasn`t aware of that, but it sounds convincing. There were a number of other machineries horizontally mounted, most of the essentials were on resilent mountings, you can see both vertical and horisontal execution on the picture below. By the way the mysterious pump mentioned above is on resilent mountings as well.
 Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 11:58
Tore,
I notice there are similar resilient mountings
in the forward torpedo room.
My observation about vertical mounted machines is based only on mechanics, physics, and a Marine's training on how to blow up machines... I yield the more functional and entirely useful aspect if running said machines to trained engineers such as your self! :-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 12:42
Christopher don`t stretch your believes in a very old mans frail memories on details from experiences more than 60 years back.
Howewer back to my theory on a possible electrical horizontal freshwaterpump for lazy younger norwegians. Down below I have indicated how the system could work and if anybody have another theory I would welcome same, this is great fun better than crossword puzzles!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 12:58
This is the kind of cross-word puzzle I like as well! As an artist, I search for clues in the same way we do on this forum... We put together ideas, we seek right understanding and after due thought, reject wrong thinking. In the end, art comes out!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 13:06
Rigth Christopher. How boring it would be if we had an answerbook to every question.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 13:38
"... Lazy young Norwegians!"... If you are typical of Lazy Norwegians, it is a Great Country Sir!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 13:46
I would sail under a man such as yourself any day! Marines led by intelligent men such as yourself have a safe berth...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 14:04
In my time we had to handpump the freshwater we consumed, even the cook had to pump all the freshwater when making the food for 46 men, the generation after me seems to have installed an electric pump in order to get rid of the exercise. Of course that would increase the freshwater consumption I believe but they migth have been a bit cleaner than we were.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 05 Jun , 2012, 14:19
Tore-
I understand about various degrees of clean... As a U.S. Marine in the First Gulf War we lived in holes dug in the sand and had only our canteen bottles of water to wash and drink from for three weeks at a time. Modern times bring better measures. Troops stationed in such places now have better equipment.  They have, perhaps, improvised, and heaven forbid... May have actually been issued better gear than they started with!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2012, 23:40
I looked at my freshwater hydrophore system this morning and wasn`t very impressed of the design. No suction to the other fw tanks, no pressuretank, no pressureswitch,in short,poor engineering. I`m posting my new idea. Blue suctionline to the common suctionline to all the fw tanks, red deliveryline via relief/pressureswitch ( I`m not 100% sure about that) connecting via the handpump supplyline to the headertank (daily consumptiontank) hopefully this would work better.
But in general I believe Simon shouldn`t bader about this system just delete it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 06 Jul , 2012, 13:57

Tore - I have a question for you and this should be one you are intimately familiar with, in that you were the designated "diver" of the KNM Kaura...
on U-570 plate 16 (http://www.uboatarchive.net/U-570Plate16.htm) item (I) shows:
TAUCHERANSCHLUSZ BACKBORD bzw STEUERBORD
Diver's connection, port or starboard

Where was this, and what type of connection was it may I ask?
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Jul , 2012, 15:05
Hi Christopher
Tore - I have a question for you and this should be one you are intimately familiar with, in that you were the designated "diver" of the KNM Kaura...

on U-570 plate 16 (http://www.uboatarchive.net/U-570Plate16.htm) item (I) shows:
TAUCHERANSCHLUSZ BACKBORD bzw STEUERBORD
Diver's connection, port or starboard

Where was this, and what type of connection was it may I ask?

I will try to answer - the german name and its translation is misleading - this is in fact "compressed air and emergency blowing manifold" (See paragraph: "Compressed air and emergency blowing manifold", page 86, http://uboatarchive.net/Manual.htm (http://uboatarchive.net/Manual.htm)).


The location - in the conning tower casing:
(http://img849.imageshack.us/img849/1093/topyy.jpg)


(http://img535.imageshack.us/img535/5512/u586viic1.jpg)




(http://img4.imageshack.us/img4/2305/u204viic3.jpg)


1 - emergency air supply connection (together with the  Taucheranschlutz)

2 - Notausblaseverter
3 - blowing valve forward
4 - blowing valve aft
(http://img580.imageshack.us/img580/3452/u570dtplate16.jpg)


(http://img600.imageshack.us/img600/4968/u570dtplate17.jpg)


U-995 was not equipped with these installation (as well as other late war U-Boats).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 06 Jul , 2012, 15:40
Oh Thanks Maciek!
I was thinking for some reason it meant the diver for the ship - not an emergency diver TO the ship! Familiar with those connections. Thanks Again!
I am working on a compilation chart to show how the various charts overlap systems. It is far from finished, but I hope it will be a useful compilation for the fine people on this group!
https://www.kabutographics.com/namen_a.html (https://www.kabutographics.com/namen_a.html)
Christopher


As a post addition, I have broken up the list into several smaller tables, linked accordingly. The tables were getting too unwieldy and large. These smaller separate lists work a bit better.
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2012, 23:13
Christopher, Maciek has already answered your question in an exellent way, I was only on the net for a few minutes yesterday before your question. The older designs of submarines a had several "solutions" to save a submarine in distress, this was one of the better. The worst solution was on some of our prewar subs, a heavy leadkeel which could be released in emergency, the trouble was that during depthcharging it had a tendency to get "off the hooks" and the sub popped up like a cork.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2012, 00:11
Christopher
I just visited your Kabutographics webside, very interesting and in fact touching one of my hobbies. Apart from modelbuilding I like to paint and am using my computer to sketch my oilpaintings. I am just busy making a painting of KNM Kaura based upon a picture of my model which I put into a choppy sea. I am posting the sketch. The oilpainting is almost finished and if of any interest I`ll mail same later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 07 Jul , 2012, 11:49
Christopher
I just visited your Kabutographics webside, very interesting and in fact touching one of my hobbies. Apart from modelbuilding I like to paint and are using my computer to sketch my oilpaintings. I am just busy making a painting of KNM Kaura based upon a picture of my model which I put into a choppy sea. I am posting the sketch. The oilpainting is almost finished and if of any interest I`ll mail same later.
Tore

Tore! Outstanding painting! My already high respect for you just tripled!


I have a number of military style paintings and pieces of artwork in my gallery, but have yet to do a submarine piece. I do intend to though!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2012, 12:48
Christopher
I have been looking at a number of submarine paintings for sale at the net and am sorry to say the quality, apart from a few honourable exceptions, is astonishing low. Some of the artists have no idea about the details as well as how a submarine behaves in open waters.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jul , 2012, 03:48
Tore,
one odd question - what was avarage wattage of bulbs used to lighting compartments?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 09 Jul , 2012, 05:39
Tore,
one odd question - what was avarage wattage of bulbs used to lighting compartments?


--
Thanks, regards
Maciek

To add to that question - were they a standard "light bulb size" or were they a particular german specific size. Would a light bulb from today fit in the sockets?
Were the colored bulbs colored by means of a gel or glass on the outside, or was the bulb itself colored?
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2012, 10:33
Ligthbulbs.
I really have to think hard to see if I remember. Contrary to our british  submarines (U class) which had bayonet sockets, the VIICs had DIN standard sockets ( screw in) and compatable to our national standard thus on our VIICs we used ordinary common (DIN) bulbs which you could get anywere in the country. As to the wattage I guess we used what we felt appropriate, mostly 60 watt for ordinary interior lamps as far as I remember, there was no code for for the wattage. I believe the coloured ligths like navigation ligths, alarmligths and nigthligths were ordinary bulbs in coloured glass. As a curiosity I previously mentioned I let the 1.st electrician install heating ligthbulbs in the officers lockers ( to keep the humidity away) these bulbs were of carbonthread type.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2012, 11:23
Ligthbulbs
I should probably mention with regards to the standard ligthbulbs bulbs being available in every place that as our standard voltage ashore is 220 V the shipvoltage is
110 V.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jul , 2012, 15:05
Tore, thank you for the reply.
To start off on a different tack - I have got a photos of handle, near the thin wall, between the officers and chief petty officers rooms, on port side. Do you remember what is it for? Can it be the handle for the schnorchel locking gear, which locks the mast in its lowered position?


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2012, 23:19
Maciek
This
Tore, thank you for the reply.
To start off on a different tack - I have got a photos of handle, near the thin wall, between the officers and chief petty officers rooms, on port side. Do you remember what is it for? Can it be the handle for the schnorchel locking gear, which locks the mast in its lowered position?

--
Thanks, regards
Maciek




Maciek
I have tried to remember this item and even if it`s almost in the wardroom I can not say for 100% I remember. However I am almost sure, as you say, it is the lockinghandle for the schnorchel in lowered position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2012, 09:57
Thank you for answer, Tore.


--
Best regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2012, 10:33
Thank you for answer, Tore.


--
Best regards
Maciek

Maciek.
Just to confirm our assumption is correct I mail a  sketch showing the two lockingpins on the schnorchelmast. Although the drawing shows a wheel for the downrigth mast I  think a handleoperated pin is probably better in that awkward position. Moreover don`t forget the schnorchel was fitted in March/April 1945 and they migth have been short of wheels at the yard in northern Norway.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2012, 12:17
Just to confirm our assumption is correct I mail a  sketch showing the two lockingpins on the schnorchelmast. Although the drawing shows a wheel for the downrigth mast I  think a handleoperated pin is probably better in that awkward position. Moreover don`t forget the schnorchel was fitted in March/April 1945 and they migth have been short of wheels at the yard in northern Norway.

Thanks Tore, great picture, where does it come from?
--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2012, 13:27
Maciek
I really don`t know. I had it for some time and I guess I found it on a dutch modelbuilders thread a few years back. But it still bugs me I don`t clearly remembered the handle from my time onboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Jul , 2012, 11:31
Hi Guys
 
I hope all you guys are having a great summer.
 
Starting to miss the U-boating already and it only the start of the winter here :( Been busy with the new job so far this winter, and it starting to look like it going to be a big winter for avalanches here, lots of snow and very cold :)
 
Happy U-boating, I can not wait to spring  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2012, 13:34
Nice to hear from you Simon. So far we haven`t had much of a summer on this end, rain every day.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 18 Jul , 2012, 07:23
Hi Guys


Tore, when sailing KNM Kaura, were the torpedo shooting excercies conducted?
If so, were ex-german torpedoes used? Was the fire control system (TDC) modernized?
How about other electronic equipment - radio transmitters and receivers and sound devices
(active sonar and hydrophones)? Were installed modern (post-war) and then, during restoration
as a musem replaced with german?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jul , 2012, 10:54
Maciek
Yes, we had intensive exercises. After work up we started with daily training of the crew by dummyattack e.g. using the fruitmachine and the other equipment like ordinary attack, but did`t actually launch a torpedo, just air. Then continued the exercises by firing dummy (not live) torpedoes at a real target ship, setting the depth at safe level so a hit- torpedo  passed well below the targetships keel. The dummytorpedo surfaced after a preset lengthrun and was catched by a special torpedofishingvessel.
I was not involved in the torpedopart so I don`t know to much on the subject, but we used ex german torpedoes, quite a stock was left behind by the germans. We mostly used the LUT torpedoes. I don`t think we modernized the firecontrol system nor the other electronic equipment. We didn`t even had a radar which worked. So in 1953-1956 we used mostly the original german equipment, but later I guess we did some  alterations. As to the U-995 at Laboe they did some strange exchange of equipment,removing the original schnorchel, the original periscope and kept a few items intalled in Norway after my time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jul , 2012, 11:42
May be somebody take interest in seeing my picture of a surfaced dummytorpedo vertically in the sea and the vessel "fishing" the torpedo. I believe I have published one of the photos before.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: wildspear on 28 Jul , 2012, 13:58
Would you debone that type of fish before cooking or would it be better to leave the skin on to keep it more tender?
 
Sorry, I had too, I thought I was quite funny.....LOL!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Jul , 2012, 15:12
 Hi Wildspear
What a question! The answer is: the fish on the picture is dead and is safe to be deboned. I would not generalize though, live fish in the same family has a tendency to make the surroundings tender if deboned or skinned. My advice would be if you are not an expert on this kind of fish and get it hooked, do not skin or debone, leave it as it is for your own health sake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: wildspear on 03 Aug , 2012, 09:49
lol
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Aug , 2012, 10:05
In the submarineslang we used very often fish for torpedo. When the torpedo was launched, the wording was:" fish in the water". Torpedoes are expensive hence an exstensive effort was done to recover same after excercises. Torpedofishing was the rigth word for it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Aug , 2012, 05:10
Hi Guys


Tore, I have one more question about Junkers compressor. Was it possible to run Junkers compressor while snorting?
Was the increased back-pressure of exhaust gases problem for the diesel compressor?
I know, that Junkers compressor exhaust manifold had its own hull valve in aft torpedo room,
but has it (outside the pressure hull) its own muffler/silencer or was it connected to main diesel engines exhaust silencers?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Aug , 2012, 23:26
Hi Maciek
We never operated the Junkers while snorting, we used only the E-compressor. As the Junker worked on a two stroke cycle, the scavenging was sensitive to exhaustbackpressure. As to the external arrangement for the silencer, I cannot remember for sure, but I would believe it was separate. I`ll  check a bit more and see if I can figure out more on the subject.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Aug , 2012, 05:22
Hi Tore
We never operated the Junkers while snorting, we used only the E-compressor. As the Junker worked on a two stroke cycle, the scavenging was sensitive to exhaustbackpressure. As to the external arrangement for the silencer, I cannot remember for sure, but I would believe it was separate.
Thank you for very interisting informations.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Aug , 2012, 08:33
Hi Gents


 

According to the upperdeck stowage, I'm attaching the part of the
"Tauchvorschrift f
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Aug , 2012, 11:15
Maciek
Indeed an interesting document.  Very comprehensive and shows the german thoroughness. I have just scanned it, we had a fairly simplyfied version, but the idea was the same. An important part of giving orders and confirmation is using standarised word for the various items and condition. It is interesting to notice that the translator is using the word "closed" emphasizing not to used the word "shut". In my time in the british RN submarine service it was the opposite, "closed" was never used, shut was the word for it. I also notice that the translators use the word "floodvalves" translated directly from german "Flutklappen". In the RN submarineenglish these valves are called Kingstons.
I am looking forward to study the document further.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Sep , 2012, 12:58
Hi


Tore, I have got a question about electric motors. On the following photos, in the upper part of motors, there is visible a shaft, perpendicular to the main shafts (red for backboard, green for starboard motor).
(http://imageshack.us/a/img13/3404/emachinen.jpg)


(http://imageshack.us/a/img221/6431/bbemachine.jpg)


Do you remember what is it for?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2012, 00:32
Maciek.
 I can not remember for 100% but here is my guess.  There are two adjusting shafts on each main motor/generator. They are situated just above the stators and I think your may see a greasecup on the shaft casing, this, I believe, is wormwheel drive connected to the shaft. By putting a handle or wheel on the shaft you are able to turn it thereby the stators and adjusting the magnetic field of the motors/generators, I don`t think we did this often.. Simon has a wonderful drawing where he has shown the system, I take the liberty to show his picture to explain what I mean.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Sep , 2012, 13:40
Hi Tore
I can not remember for 100% but here is my guess.  There are two adjusting shafts on each main motor/generator. They are situated just above the stators and I think your may see a greasecup on the shaft casing, this, I believe, is wormwheel drive connected to the shaft. By putting a handle or wheel on the shaft you are able to turn it thereby the stators and adjusting the magnetic field of the motors/generators


That would be it! Accidentaly, in book "Die Sonar Anlagen der deutschen U Boote" by Eberhard R
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Sep , 2012, 14:30
Maciek
Excellent! As I said I cannot remember we used it. We had more problems with the propellernoise as the propellors on the later VIICs were made of cast steel. They were susceptible to cavitationpittings which again produced noise. The resilient mountings for the various auxilliaries were checked during annual noisetrials and if some component failed we had to fix it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 28 Sep , 2012, 04:28
Thanks Tore.


I have got another question. When you were snorting, it was common practice to propelling boat
with one shaft or two? And while running on E-motors? It would be better to drive with one shaft
or two (I'm referring to low speeds)?


--
Thanks
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Sep , 2012, 10:18
Maciek
We tested various alternatives and ended up with one diesel charging the batteries, eg coupled to the generator, tailclutch disconnected, and the other E-motor driving the propeller, diesel disconnected. Propelling the sub by E-motors made it easier (softer) to handle the snorting condition for the hydroplanepeople ( steady snortingdepth). Several times during direct dieseldriven propellers we dipped the snortmast floatvalve resulting in very uncomfortable air pressurefluctuations and sometimes the safetyvalve on the exhaust opened filling the sub with black exhaust. Snortingpropulsion by E-motors was definitely the most favourable alternative.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 Sep , 2012, 13:50
Hi
I can not remember for 100% but here is my guess.  There are two adjusting shafts on each main motor/generator. They are situated just above the stators and I think your may see a greasecup on the shaft casing, this, I believe, is wormwheel drive connected to the shaft. By putting a handle or wheel on the shaft you are able to turn it thereby the stators and adjusting the magnetic field of the motors/generators


That would be it! Accidentaly, in book "Die Sonar Anlagen der deutschen U Boote" by Eberhard R
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 Sep , 2012, 13:58
Tore
We tested various alternatives and ended up with one diesel charging the batteries, eg coupled to the generator, tailclutch disconnected, and the other E-motor driving the propeller, diesel disconnected. Propelling the sub by E-motors made it easier (softer) to handle the snorting condition for the hydroplanepeople ( steady snortingdepth). Several times during direct dieseldriven propellers we dipped the snortmast floatvalve resulting in very uncomfortable air pressurefluctuations and sometimes the safetyvalve on the exhaust opened filling the sub with black exhaust. Snortingpropulsion by E-motors was definitely the most favourable alternative.
And when crusing submerged at low speed, wheter snorting or using battery, it was better to use one shaft or two? I mean, if boat had some better characteristics (ie reaction on helm), or it was meaningless?
--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Sep , 2012, 00:30
M
Hi
I can not remember for 100% but here is my guess.  There are two adjusting shafts on each main motor/generator. They are situated just above the stators and I think your may see a greasecup on the shaft casing, this, I believe, is wormwheel drive connected to the shaft. By putting a handle or wheel on the shaft you are able to turn it thereby the stators and adjusting the magnetic field of the motors/generators


That would be it! Accidentaly, in book "Die Sonar Anlagen der deutschen U Boote" by Eberhard R
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Sep , 2012, 00:49
Tore
We tested various alternatives and ended up with one diesel charging the batteries, eg coupled to the generator, tailclutch disconnected, and the other E-motor driving the propeller, diesel disconnected. Propelling the sub by E-motors made it easier (softer) to handle the snorting condition for the hydroplanepeople ( steady snortingdepth). Several times during direct dieseldriven propellers we dipped the snortmast floatvalve resulting in very uncomfortable air pressurefluctuations and sometimes the safetyvalve on the exhaust opened filling the sub with black exhaust. Snortingpropulsion by E-motors was definitely the most favourable alternative.
And when crusing submerged at low speed, wheter snorting or using battery, it was better to use one shaft or two? I mean, if boat had some better characteristics (ie reaction on helm), or it was meaningless?
--
Thanks, regards
Maciek
Snorting.
Generally speaking the sub had the best performance operating on two propulsionshafts, you did not have to compensate so much on the helm and the aft hydroplanes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2012, 01:56
Drifting a bit far from my normal topics I thought I should show you my recently completed showstand I made in my hobbyshop. The idea was to have have a piece of furniture that would give my wife's approval to have my model of KNM Kaura ex U995 in the sittingroom. As your see I have fitted LED ligth from top as well at the bottom. The latter was necessary in order to show the Kingstones (Flutklappe).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 16 Oct , 2012, 11:20
Beautiful, i like it!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 16 Oct , 2012, 19:49
Tore, That looks outstanding! I may have to build something like that when I build my U-35 cut-away! I actually like the "flood-lighting" for the Flutclappe!


Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2012, 13:26
Hi Tore/SnakeDoc

I have finished another season in the snow, so I have time to continue working on U-1308. I have started to reread our old posts to refresh my mind about our discussion. This brings me back to the low pressure air sea weed air blowing cleaner system.

http://models.rokket.biz/index.php?topic=921.msg11832#msg11832 (http://models.rokket.biz/index.php?topic=921.msg11832#msg11832)

We initial presume that the small pipes (approximately 20 mm - purple color) were the low pressure line for this system, but I not to sure anymore, here why.
I now believe these are the correct pipe (Green arrow) for the cleaner system.

PS. Tore, the display looks great.

(http://imageshack.us/a/img90/5969/seaweedp.jpg)
Port Side
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))

(http://imageshack.us/a/img840/5523/seaweedsb.jpg)
Starboard Side
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2012, 14:50
Simon welcome back from the snow, we are already getting some on this end and you are welcome to come over and move it away. As to the weedblowing system you are absolutely rigth. On the systemdrawings below I have indicated the way it is.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2012, 14:55
Hi Tore

Q: About the lubeoil separator (centrifuge) - Reply #355 to 358. http://models.rokket.biz/index.php?topic=921.msg11874#msg11874 (http://models.rokket.biz/index.php?topic=921.msg11874#msg11874)

Tore, do you know where the two lube oil separator are found? Are there under the decking?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2012, 15:08
I cannot remember where, but I believe it was only one and according to the systemdrawings it seems to have been mounted on the port side forwd. It migth have been under the floorplating.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2012, 15:14
I cannot remember where, but I believe it was only one and according to the systemdrawings it seems to have been mounted on the port side forwd. It migth have been under the floorplating.
Tore

Thanks, starting to all come back to me. I will have a look at a few drawings and see if I can workout something.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2012, 15:18
Hi Tore/SnakeDoc

Does anyone know where the LP piping enter the engine room? Above or below/Port or starboard side?

I would think below deck and on the port side as the manifold in the Control Room was on the port side ???


(http://imageshack.us/a/img152/2976/new2on.jpg)
(source: http://uboatarchive.net (http://uboatarchive.net/))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2012, 15:34
Tore, the flow meter next to the lube oil separator, would it look similar to the one found in the forward torpedo? Thanks, Simon.

http://models.rokket.biz/index.php?topic=106.msg8197#msg8197 (http://models.rokket.biz/index.php?topic=106.msg8197#msg8197)

(http://img442.imageshack.us/img442/5314/new2su.jpg)
(source: http://uboatarchive.net (http://uboatarchive.net/))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2012, 23:52
Simon
I think quite a few items, including the flowmeter is intergrated in the luboilseparatorunit. Below within the black framing is my idea what`s in the separatorunit. I don`t believe the flowmeter is identical to the torpedocompensatingtank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Oct , 2012, 00:24
Thanks, Tore.

Here a idea. I was looking the piping layout, and I noted a funnel section next to the luboilseparatorunit. In the photo below you can see a funnel section (Red arrow) and maybe the luboilseparatorunit is the blue arrow?

(http://imageshack.us/a/img706/7304/new1ym.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2012, 00:29
Simon
LP airpipeline.
I`m not 100% sure, but I believe the main LP air supplypipe is going on the top center (midship) into the engineroom. I`ll check and see if I have a better idea later
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2012, 00:50
Siomon
Your suggestion seems to be a possibility, howewer I cannot see the the access to the separatorbowl, it looks awfully cramped bearing in mind that it had to be dismantled and cleaned quite frequently ( I never did the job so my memory is blanked ).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2012, 06:15
Simon
In order to know what to look for may be an understanding of the purifierpiping would help. The system is separated from the engine lubeoilsystem, only connected via the lube oiltanks.  You have two pumps one for dirty and one for clean oil. There are two heaters, one for the "washingwater" and one for the dirty lubeoil. When the engines are running, the warm coolingwater from the exhaustmanifold is used and enter via the washingwater heater, in this case probably not to be used. When the engines are stopped, cold water from the seainlet is entering the heater and heated before added to the purifier. The dirty oil is taken from either the dirty oiltank, or stb and port engine lubeoil system tanks,entering the purifier lubeoil heater heated if needed and afterwards mixed with the warm washingwater from the waterheater and fed to the purifier. I have added colours to the systemsketch below. Red warm washingwater, blue cold washingwater, green dirty lubeoil and yellow clean lubeoil, the black is sludge. As I said I believe a lot of the stuff is intergrated in the purifier. We really need a picture of the actual purifier.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Oct , 2012, 12:26
A big thanks, Tore. Help a lot!  :) :) 

I have a few questions.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Oct , 2012, 15:29
Tore, I spend the morning searching and studying the photo's I have. I have located a 2nd smaller funnel section next to the one I found in Reply #466. I have yet to found any funnel section on the port side of the boat. Because I found no funnel section on the port side, and two on the starboard side this adds more weight that the luboilseparatorunit is located on the starboard side of the boat.


Siomon
Your suggestion seems to be a possibility, howewer I cannot see the the access to the separatorbowl, it looks awfully cramped bearing in mind that it had to be dismantled and cleaned quite frequently ( I never did the job so my memory is blanked ).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2012, 16:09
Simon.
Dirty oil stored in the dirty oiltank gets cooled hence a higher viscosity and makes it more difficult to separate impurities. Lube oil in the enginesystem (tanks) when the engines are running gets warm and mostly don`t have to be heated. If the engine stops the lubeoil in the system tanks get cooled and needs to be heated to have the rigth purifying viscosity. You might want to clean the lube oil if the engines are not running.
The condition of the lubeoil ( impurities) might vary according to the engineservice, combustion, waterleakages etc. and the frequencies of the purifying, but you run the purifier quite often some times continuously.
The purifierpumps are always running simultaneously when the purifier is in operation, you need both in order to get dirty oil to the purifier and clean oil out of the purifier.
The pumps of the purifier has nothing to do with the attached lubeoil pumps for the engines , I believe they are normally driven by the purifier (intergrated).
The construction of the pumps are normally gear or IMO pumps.
Your last question is probably answered above, I believe non of the pumps are driven by the engines, you want to be able operate the purifier even when the engines are stopped.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2012, 00:03
Hi Simon

Q: About the lubeoil separator (centrifuge) - Reply #355 to 358. http://models.rokket.biz/index.php?topic=921.msg11874#msg11874 (http://models.rokket.biz/index.php?topic=921.msg11874#msg11874)

Tore, do you know where the two lube oil separator are found? Are there under the decking?


I'm attaching the drawing, where I had marked the location of the oil purifier. I think, that it is located in the middle, just
behind the hatch to the engine room, under deck plating.
 
Here a idea. I was looking the piping layout, and I noted a funnel section next to the luboilseparatorunit. In the photo below you can see a funnel section (Red arrow) and maybe the luboilseparatorunit is the blue arrow?

(http://imageshack.us/a/img706/7304/new1ym.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))



Well, according to my guesses, on this photo you have marked the auxiliary cooling water pump.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2012, 01:53
Maciek
 I believe you are rigth. On your very detailed drawing I cannot figure out anything which looks like a purifier. According to the RN report on U-570 the lubeoil purifier installed was no 149 Type 2LHD 2/20 capacity 300 l/h Ramesohl & Schmidt, Westfalia, Oelde. The motor manufacturer was Werdohler Pumpenfabrik, Werdohl I/W Paul Hillebrand GMBH. A picture of that separator/purifier would help a lot.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2012, 01:56
Does anyone know where the LP piping enter the engine room? Above or below/Port or starboard side?

I would think below deck and on the port side as the manifold in the Control Room was on the port side ???
 

LP airpipeline.
I`m not 100% sure, but I believe the main LP air supplypipe is going on the top center (midship) into the engineroom. I`ll check and see if I have a better idea later


I also think, that low pressure air line is led under the ceiling, midship (that is general pattern in german design :). I will try figure out which one is it.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2012, 02:18
I think quite a few items, including the flowmeter is intergrated in the luboilseparatorunit. Below within the black framing is my idea what`s in the separatorunit. I don`t believe the flowmeter is identical to the torpedocompensatingtank.


I agree with Tore, that oil purifier could be integrated with such elements as flow meter, heaters, and so on.


(http://imageshack.us/a/img706/7304/new1ym.jpg)


Simon, on this photo, I'm wondering about the spring, which is located above the funnel. Together it does not look like part of oil purifier.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Oct , 2012, 12:26
Hi Maciek & Tore

Thanks for the updated information :)

I think you are correct about the oil purifier being central line, it makes more sense to keep all this system together.

You are also correct about the photo in the last post below. I think I workout it out last night it part of the Fuel oil compensating system (circulating water under pressure) (Plate 10). In the photo you can see:
(http://imageshack.us/a/img580/3319/new2ab.jpg)
(source: http://uboatarchive.net (http://uboatarchive.net/))

 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2012, 14:20
Simon
I guess you have pretty much an idea of the inboard pressure water fuelcompensating system forward portside of the engineroom, anyhow below is a picture of the first valves after entering the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2012, 14:55
I think quite a few items, including the flowmeter is intergrated in the luboilseparatorunit. Below within the black framing is my idea what`s in the separatorunit. I don`t believe the flowmeter is identical to the torpedocompensatingtank.


I agree with Tore, that oil purifier could be integrated with such elements as flow meter, heaters, and so on.


(http://imageshack.us/a/img706/7304/new1ym.jpg)


Simon, on this photo, I'm wondering about the spring, which is located above the funnel. Together it does not look like part of oil purifier.


--
Regards
Maciek

Maciek.
I believe the spring you are wondering about is the spring for the reliefvalve for the enginedriven pistoncooling-waterpump of the starboard engine. You can see the   reliefvalve for the port engine under the horizontal freshwaterpump on port side.  Simon I don`t think this has anything to do with a purifier.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2012, 16:41
Simon
I guess you have pretty much an idea of the inboard pressure water fuelcompensating system forward portside of the engineroom, anyhow below is a picture of the first valves after entering the pressurehull.
Tore

Thanks for the correct information :) :)

Maciek.
I believe the spring you are wondering about is the spring for the reliefvalve for the enginedriven pistoncooling-waterpump of the starboard engine. You can see the   reliefvalve for the port engine under the horizontal freshwaterpump on port side.  Simon I don`t think this has anything to do with a purifier.
Tore

Yes, your total correct. I am trying to decide if I am going to add the purifier system to my drawing. We have some little information it and I would hate to add something to my drawing that was only a best guess :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2012, 16:44
This morning I added the main drainage line and the Main drain suction valve (with the extension control for the neighbouring compartment).

Tore, there no pictures of this valve, but what do you think of my drawing of the valve? Looks OK?

(source: http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm))

(http://imageshack.us/a/img33/564/new1qs.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Oct , 2012, 23:07
Tore
I believe the spring you are wondering about is the spring for the reliefvalve for the enginedriven pistoncooling-waterpump of the starboard engine. You can see the   reliefvalve for the port engine under the horizontal freshwaterpump on port side.  Simon I don`t think this has anything to do with a purifier.


Thank you for clarification! Now it makes sense to me.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Oct , 2012, 23:26
Hi Simon
Tore, there no pictures of this valve, but what do you think of my drawing of the valve? Looks OK?


Here you got similar valve, which is located just behind the control room bulkhead (in Petty Officers Room):


(http://imageshack.us/a/img24/5955/valven.jpg)


Tore, does it the same type as in Diesel engine room?


The other side of bulkhead with shaft passing through looks following:




(http://imageshack.us/a/img411/4536/valve2u.jpg)


(http://imageshack.us/a/img152/1530/valve3.jpg)




Maybe it somehow helps.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2012, 23:59
Thanks Maciek! I will update my drawing tomorrow :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2012, 00:34
Thanks Maciek! I will update my drawing tomorrow :)
Simon.
If you wonder how it looks like on the other side, engineers PO`s mess, you may see a very young EO checking it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2012, 00:41
Simon
I guess you have pretty much an idea of the inboard pressure water fuelcompensating system forward portside of the engineroom, anyhow below is a picture of the first valves after entering the pressurehull.
Tore

Thanks for the correct information :) :)

Maciek.
I believe the spring you are wondering about is the spring for the reliefvalve for the enginedriven pistoncooling-waterpump of the starboard engine. You can see the   reliefvalve for the port engine under the horizontal freshwaterpump on port side.  Simon I don`t think this has anything to do with a purifier.
Tore

Yes, your total correct. I am trying to decide if I am going to add the purifier system to my drawing. We have some little information it and I would hate to add something to my drawing that was only a best guess :(

Simon
 A very wise idea! The whole thing is a real puzzle to me, the more so because I cannot remember a thing about the lube oil separator/ purifier.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2012, 01:13
Simon.
Remote operated bilgevalve.
I got sligthly confused by the yellow black zebrastripes and the new aluminium floorplating now fitted on the Laboe U 995. The picture is indeed from the same side as my picture, but of course the bilgepipe goes to the aft batterycompartment.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Oct , 2012, 01:14
Thanks Maciek! I will update my drawing tomorrow :)
Simon.
If you wonder how it looks like on the other side, engineers PO`s mess, you may see a very young EO checking it.
Tore

Thanks for the picture.

Here a picture of the handle in the moter room as the valve are under the decking.
(http://imageshack.us/a/img801/9400/new1nx.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2012, 06:29
This morning I added the main drainage line and the Main drain suction valve (with the extension control for the neighbouring compartment).

Tore, there no pictures of this valve, but what do you think of my drawing of the valve? Looks OK?

(source: http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm))

(http://imageshack.us/a/img33/564/new1qs.jpg)
Simon.
I just had a look at your drawing of the bilgevalve in the engineroom. It seems to me that the valve is placed on port side fairly close to the dirtyoil handpump and could be remote operated from the E-room, shouldn`t this  be the opposite, eg. the bilgevalve placed in the E-room with the possibility to operate same from the engineroom? I should think the engineroom bilgevalve migth be placed more to the stb side close to the E-room bulkhead and able to be controlled from the E-room side. Just an idea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2012, 07:42
Simon.
To follow up my remarks I`m posting the systemsketch in the relevant area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2012, 01:36
It been very hard to work out how the remote operated bilge valve works.

You can see the double handle in the picture in Reply #488. By lifting the handle, the control rod (WHITE) rises and opens the valve. The control rod (WHITE) is linked to a wheel (RED) and rotates a cross over rod (Yellow) to the other wheel (Red) which move the other handle.

Tore/Maciek, what do you think of this system?   

(http://imageshack.us/a/img11/4510/90314101.jpg)
(http://imageshack.us/a/img72/2550/46428941.jpg)
(http://imageshack.us/a/img854/276/35801466.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2012, 08:41
Simon
Clever design :) . I`m not sure I fully understand your twin operated valves though. On the picture below I have indicated with red arrows the similarities between the valve in the E-rom and the POs mess, I believe they are possibly identical. With the yellow arrow I suggest this might possibly be the separate E- roomhandle for an identical valve in the engineroom, thus the you see the top of the valvecasings on both pictures which mean no extensionrods.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2012, 11:10
Hi Tore

Yes, I believe this valve is complex without better photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2012, 12:28
Hi Tore

I started adding the engine mount for the starboardengine, does it look Ok to you?

(http://imageshack.us/a/img411/6493/new1ns.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2012, 13:01
Hi Tore

Yes, I believe this valve is complex without better photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2012, 13:10
Simon.
So far so good, usual high class standard. Looking forward to the rest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2012, 13:21
Hi Tore

Yes, I believe this valve is complex without better photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2012, 07:17
Simon
Drainage/flooding valves.
I believe we have to look to the working  of the system. The main drainage/flooding main pipe goes all the way from fwd. to aft, being able to bring the water in both direction. In those areas not centrally controlled you have branchoff pipes locally controlled, in some areas these branchoff pipes are fitted with controlled checkvalves shutting the branchoff to the mainpipe by a spring. The vital valves can be controlled from two positions, locally at the valve or via a shaft through a watertight or even pressuretight bulkhead adjacent to the valve.
 I believe basically all the handcontrolled checkvalves are the same and the pictures of the checkvalves shows the top of the valves, the reason is that you clearly see a centrally placed watertight stuffingbox for the valvespindle,  a lengthening rod would have a simple guidebush.
The  support on the valvetop accommodating a horizontal shaft going through a bulkheadsealing to a handle in the adjacent compartment. On this shaft is fixed an excentric disc ( cam ) able to touch the top of the valvespindle. Locally at the valve is another handle different from the other as it contains a screwspindle ( see the  square tap at the end) and at the other end a forked bush enclosing the horizontal shaft but not fixed to same.
Shutting and opening the valve is as follows:

1. Opening.Turning the shaft by a handle in the adjacent compartment cause the excentric disc ( cam) to force down the valvespindle, opening the valve against the springpressure. The screwhandle locally at the valve is not connected to the shaft and is not moving ( to avoid in case of emergency something should block the handle.) Shutting. Turning the shaft the  other way and the spring is shutting the valve
2. The most common situation. In case of locally drainage (bilgepumping ).Opening. A wheel or handle is put on the  square turning the spindle inwards thus locking the handle to the shaft. Turn the handle up against its stop (clearly visible) thereby moving the shaftcam about 90 degrees and opens the valve.
Shutting. Putting the screwhandle down to the other stop releasing the valvespindle and the spring shuts the valve. Unscrew the handle from the shaft.

The picture of the handle in the E-room looks indeed as connected to the checkvalve, it could be this is a handle on the shaft through the bulkhead for the same valve, because you cannot see any bulkhead bushing for the horizontal checkvalve-shaft. A reason could be that it had to be displaced and hence a crankconnection had to be made for the rotating camshaft for the checkvalve.
Well a long story about a relatively simple valve, but it`s the only idea I have for the moment.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2012, 09:22
Drainage/floodvalves.
Have read my ideas in retrospect I`m not 100% satisfied. I believe it is room for improvement. The only thing I`m sure of is, on the photos we see the top of the valvecage, the horizontal shaft and a fairly simple valvemechanism for the controlled checkvalve. No complicated gearwheels. So I`m open for alternatives we got to get Simons drawing correct..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Oct , 2012, 12:26
I think you right, I am sure the Germans keep this valve simple. We just need a few more good photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2012, 13:06
Yes Simon let`s have a few more photos !
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Oct , 2012, 13:15
Tore, do you think the drainage pipe that runs between the aft trimming tank to the Control Room manifold and valve h be the same diameter as the drainage pipe we been working on?

http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Oct , 2012, 14:37
(http://imageshack.us/a/img525/5098/53780889.jpg)
Fig. 1. Drainage line (Brown-green-brown).

Tore, why you do you think the German, added a kink in the piping between the two frames?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2012, 14:43
Simon.
Tore, do you think the drainage pipe that runs between the aft trimming tank to the Control Room manifold and valve h be the same diameter as the drainage pipe we been working on?

http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm)
Simon.
It migth be a bit smaller. The drain/flooding pipe should be able to handle large quantities of water, whereas the trimline usually handled moderate quantities. F.inst. when the order divingstations was given and the  crew moved to their station I remember 400 ltrs had to be pumped from aft trimtank to fwd. On a special occasion we flooded the diesel inlet shaft from the towercasing to the shut hullvalve in the engineroom, I guess it contained several tons of seawater which had to be drained into the engineroom bilge and pumped out via the drain/floodpipe in a hurry. It  should be possible to find the exact diameters though.
Tore
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Oct , 2012, 15:22
Simon.
Tore, do you think the drainage pipe that runs between the aft trimming tank to the Control Room manifold and valve h be the same diameter as the drainage pipe we been working on?

http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm)
Simon.
It migth be a bit smaller. The drain/flooding pipe should be able to handle large quantities of water, whereas the trimline usually handled moderate quantities. F.inst. when the order divingstations was given and the  crew moved to their station I remember 400 ltrs had to be pumped from aft trimtank to fwd. On a special occasion we flooded the diesel inlet shaft from the towercasing to the shut hullvalve in the engineroom, I guess it contained several tons of seawater which had to be drained into the engineroom bilge and pumped out via the drain/floodpipe in a hurry. It  should be possible to find the exact diameters though.
Tore
Tore

Thanks Tore. I estimated the main drainage pipe to have a diameter of 120 mm, what do you think of about 80 mm for the other pipe?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 00:14
Simon
As a further guidance, the main drainpump (sentrifugal) had a capacity of 75 cub m/hour (impellors in paralell, low head) and 30 cub m/hour ( impellors in serial, high head) otherwise the capacity variation follows the normal sentrifugalvariation depending of the head. The trimpump (aux bilgepump, double piston) had a capacity of 18 cub/hour being a constant capacity as for pistonpumps. Thus the max. capacity of the main drainpump is about 4 times that of the trimpump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 01:14
(http://imageshack.us/a/img525/5098/53780889.jpg)
Fig. 1. Drainage line (Brown-green-brown).

Tore, why you do you think the German, added a kink in the piping between the two frames?
Simon.
I was not aware of this bend. My only idea is as follows: The diesel engineblock is casted in two parts joined by a flange right in this area. The steelstructure under the engine is pretty close to the to casted engine crankcase flange ( see picture below), may be they had to lead the pipe just around this flange. From an engineering point of view this is bad, almost unbelievable, but it is the only idea I have right now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 01:52
Simon
I just had a look at your maindrain/flooding pipe drawing in the engine room. It seems that your pipe goes down and through the lubeoil storage tank. In general you would`t have a massive waterpipe in a vital lubeoiltank. If you are sure about that, my idea above is of cause not relevant.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Oct , 2012, 02:33
Simon
I just had a look at your maindrain/flooding pipe drawing in the engine room. It seems that your pipe goes down and through the lubeoil storage tank. In general you would`t have a massive waterpipe in a vital lubeoiltank. If you are sure about that, my idea above is of cause not relevant.
Tore

Hi Tore

I completely forgot about the lube oil storage tanks, but this pipe goes through the port tank. I will update my drawing tomorrow.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 04:16
Simon.
I would have no idea why the pipe has a bend in the middle of the lubeoil storage tank, I can see nothing there which necessitates such a bend.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Oct , 2012, 12:17
Simon.
I would have no idea why the pipe has a bend in the middle of the lubeoil storage tank, I can see nothing there which necessitates such a bend.
Tore

Could it be something to do will reducing shock loading down the pipe line?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 13:13
I don`t think so Simon, on some steampipes we used such bends to take up heatexpansion, but I don`t see the temperaturevariation should justify that on such pipe.
Have you any ideas why the drawing does not show the two handcontrolled checkvalves or drainage/flooding branchoff in the engineroom?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Oct , 2012, 15:41
(http://img259.imageshack.us/img259/9723/76407420.jpg)
Fig. 1. Display the cover of the lubeoil storage tanks.


(http://img402.imageshack.us/img402/5862/68311547.jpg)
Fig. 2. Display the main engine frame.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2012, 23:50
Simon.
This is more to my liking. It remains to figure out the remote handoperated checkvalves though. It is a vital part of the system that you should be able to open and shut that valve from the adjacent watertight compartment.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2012, 08:56
Flood/drainvalve fwd engineroom.
 With the help of U-historia I believe I might have located the fwd engine room drain/floodvalve. First of all there are only ordinary valves draining batterycompartment into the engineroom, draining of the waste watertank is done via an ordinary checkvalve up fwd PO mess or probably in the controlroom. Flooding of the batterycomp. is done from the valve fwd PO mess. The only handcontrolled checkvalve operated from the adjacant compartment in fwd engineroom is possibly situated up towards the bulkhead of the main batteryswitch compartment no. 2, stb side of the galleydoor. Allthough the hand operatingshaft through the bulkhead is indicated by U-historia to be right down of the dooropening, I think it might be a fair chance that same could be situated in the switchcompartment,  I cannot figure out it is outside. Thus this is no 3  of these 4 valves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Oct , 2012, 11:28
Tore, in the galley there are two hatches on the floor. They could be for port side valves  :)

(http://img94.imageshack.us/img94/6821/new1qx.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2012, 13:02
I think they probably are Simon. Fwd hatch the handcontrolled stop check valve for the wastewatertank, the aft port hatch for the handcontrolled valve for gravetydraining from the galley to the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Oct , 2012, 13:23
Air Engine Starting System

Tore, I was wondering if you can help me with this system http://www.uboatarchive.net/U-570Plate15A.htm (http://www.uboatarchive.net/U-570Plate15A.htm) I have a few questions.


Thanks, Simon.
(http://imageshack.us/a/img706/3469/new4fi.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Oct , 2012, 14:02
Dorsal view of the Engine

To be able to increase the detail and accurate of my drawing of the engine, I need to draw the dorsal view at the same time, so I am going to start this today and here are my first round of questions.

1. On the rocker arm the left arrow is this just a casting mark? Or is there something missing?
2. Right arrow, I imagine this is a grease point, is this just a small nut?

(http://img832.imageshack.us/img832/7369/new5r.jpg)


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2012, 14:29
Simon.
Starting air flask.
The drawing for the startingair supply is for MAN engines, the picture from the U 995 is of  Krupp Germaniawerft engines and they have different startingsystem. Howewer the startingair supply is the same principle. The drain on the starting airvessel I presume is just the waterblow off from the vessel and has not anything to do with the induction air. The waterdrain from the airvessel goes via a funnel to the bilge. The valves on the engines is probably a bit different between the MAN engine and the GW engine but I believe you have found the reducingvalve 205-30 Bar.  I believe the other valves are hidden by the maneuverstand .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2012, 14:58
Dorsal view of the Engine

To be able to increase the detail and accurate of my drawing of the engine, I need to draw the dorsal view at the same time, so I am going to start this today and here are my first round of questions.

1. On the rocker arm the left arrow is this just a casting mark? Or is there something missing?
2. Right arrow, I imagine this is a grease point, is this just a small nut?

(http://img832.imageshack.us/img832/7369/new5r.jpg)



The valve rocker arms are pivoting on a shaft fixed to the rockerarm support, thus you don`t lubricate the two points. The small excessive painted knobs could be  small nuts locking the shafts to the supports.
On the rocker arm in the center, the point just above the shaft where it is pivoting should be lubricated.  I cannot remember for sure, but I believe it was handlubricated and not by a line from the lubricator up front.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2012, 15:34
Simon
I just checked some of  my pictures, there were no lubricatorpipes to the rockerarms, I belive just a cavity for handlubrication.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Oct , 2012, 17:50
Dorsal view of the Engine

Not very exciting today, just the start ;D

(http://img202.imageshack.us/img202/1909/engineroom1.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Oct , 2012, 02:13
Simon
It seems right to me. Knowing you love tiny details, the shaft for the forked end of the pushrod is protruding slightly out of the rockerarm on both sides, this to accommodate a small grove where you have a spring lockingring you know the type having a split fitted with a set of pliers. On the other side of the rockerarm on the top of the valvespindle is a special pressuredisc fixed by a nut locked by wire. Se picture below.
Tore.. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Oct , 2012, 02:20
Simon
Starting air vessel for GW engines. Below is the starting air supplysystem for the GW engine, not much difference.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Oct , 2012, 03:40
Air starting system.
The startingsystem of the GW engine might look a bit complicated, but is relatively simple compaired to the reversingmechanism. Below is an isometric drawing of the system. The starting airvalve on each cylindercover is operated by a pushrod from the camshaft. The pushrod is normally kept free from the camshaft by a spring, it is the only rod on the Laboe U 995 engine which is not painted blue, originally it was not painted at all. When the  main air startingvalve ( red wheel ) is opened pressureair is admitted to a chamber with piston ( slide) in the startingvalve on the cylindercover and forces the rod down against the springpressure to the camshaft. When the maneuvre startinghandle on the manuevrestand is put to start position, air is admitted to the cylinder startingvalve air chamber and that valve which is opened by the camshaft admit the air to the cylinder and the engine start turning by air. When the engine obtain sufficient revs. fuel is admitted to the fuelvalves and the engine is running. Then the startinghandle is put on run position, the  main airvalve is shut the air is relieved and the starting air valve in the cylindercover is raised free from the camshaft by the spring.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Oct , 2012, 07:19
Simon.
As a more detailed explanation I `m posting a drawing showing the difference between the MAN and GW starting air supply. Basically as previously said they are the same. The main difference is that the GW engines is charging the starting airvessel via one reducingvalve 205-30 atm and thus don`t require further reducingvalves on the engine.
MAN is charging the airvessel via an air reducing valve 205-75 atm and require a second reducingvalve 75-30 atm after the main starting airvalve on the engine. You shall find quite a lot of further differences when you make you dorsal drawing so I guess you have to stick to one enginemakes  and matching you pipesystems, so far it seems you have chosen GW engines and of course the GW pipesystem should be chosen.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Oct , 2012, 16:38
Simon
It seems right to me. Knowing you love tiny details, the shaft for the forked end of the pushrod is protruding slightly out of the rockerarm on both sides, this to accommodate a small grove where you have a spring lockingring you know the type having a split fitted with a set of pliers. On the other side of the rockerarm on the top of the valvespindle is a special pressuredisc fixed by a nut locked by wire. Se picture below.
Tore..

Hi Tore

Thanks for the information :)

I did noted the spring locking ring and added this to the drawing. I don't think you will see it at 1:32 scale in the drawing but if anyone ask me I can say it there ;D ;D

I am going to work on the other end of the rocker arm on Wednesday, I am going ski touring tomorrow as I went to collect some avalanche and snow data.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2012, 00:15
Simon.
Thought you was satisfied with snow for this year, we had our first snowfall for the season this morning, even way down in the lowland. I have to brace for the winter putting on the wintertyres with studs. Looking forward to se your drawing of the engine topview it`s a lot of stuff cramped on to the cylindercover. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 31 Oct , 2012, 01:38
Hi Gents


A little bit off-topic - I have found following (another) panorama - I think you will like it:
http://www.360cities.net/image/submarine-u-995-and-navy-memorial#328.70,-5.00,75.0


Just to remind another U-995 virtual tours:
http://www.deutschland-panorama.de/museen/laboe_technisches_museum/index.php
http://www.kubische-panoramen.de/index.php?id_id=5373&p=i


And in the end, virtual tours around other U-Boats:
Wilhelm Bauer (Ex U-2540): http://www.kubische-panoramen.de/index.php?id_id=4602&p=
U-505: http://archive.msichicago.org/exhibit/U505/virtualtour/index.html
Vesikko: http://www.360cities.net/image/wwii-nazi-submarine-exterior#338.20,0.90,88.3
http://www.kolumbus.fi/mika.ajomaa/Panorama_2.html


--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Oct , 2012, 02:35
Hi Gents


A little bit off-topic - I have found following (another) panorama - I think you will like it:
http://www.360cities.net/image/submarine-u-995-and-navy-memorial#328.70,-5.00,75.0 (http://www.360cities.net/image/submarine-u-995-and-navy-memorial#328.70,-5.00,75.0)


Just to remind another U-995 virtual tours:
http://www.deutschland-panorama.de/museen/laboe_technisches_museum/index.php (http://www.deutschland-panorama.de/museen/laboe_technisches_museum/index.php)
http://www.kubische-panoramen.de/index.php?id_id=5373&p=i (http://www.kubische-panoramen.de/index.php?id_id=5373&p=i)


And in the end, virtual tours around other U-Boats:
Wilhelm Bauer (Ex U-2540): http://www.kubische-panoramen.de/index.php?id_id=4602&p= (http://www.kubische-panoramen.de/index.php?id_id=4602&p=)
U-505: http://archive.msichicago.org/exhibit/U505/virtualtour/index.html (http://archive.msichicago.org/exhibit/U505/virtualtour/index.html)
Vesikko: http://www.360cities.net/image/wwii-nazi-submarine-exterior#338.20,0.90,88.3 (http://www.360cities.net/image/wwii-nazi-submarine-exterior#338.20,0.90,88.3)
http://www.kolumbus.fi/mika.ajomaa/Panorama_2.html (http://www.kolumbus.fi/mika.ajomaa/Panorama_2.html)


--
Regards
Maciek

Thanks Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Oct , 2012, 02:40
I think you right, I am sure the Germans keep this valve simple. We just need a few more good photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2012, 03:30
Hi Gents


A little bit off-topic - I have found following (another) panorama - I think you will like it:
http://www.360cities.net/image/submarine-u-995-and-navy-memorial#328.70,-5.00,75.0 (http://www.360cities.net/image/submarine-u-995-and-navy-memorial#328.70,-5.00,75.0)

Maciek
Absolutely gourgeous! This shall answer a lot of questions here we have a tool to solve a lot of our mysteries.
 Well done.
Tore


Just to remind another U-995 virtual tours:
http://www.deutschland-panorama.de/museen/laboe_technisches_museum/index.php (http://www.deutschland-panorama.de/museen/laboe_technisches_museum/index.php)
http://www.kubische-panoramen.de/index.php?id_id=5373&p=i (http://www.kubische-panoramen.de/index.php?id_id=5373&p=i)


And in the end, virtual tours around other U-Boats:
Wilhelm Bauer (Ex U-2540): http://www.kubische-panoramen.de/index.php?id_id=4602&p= (http://www.kubische-panoramen.de/index.php?id_id=4602&p=)
U-505: http://archive.msichicago.org/exhibit/U505/virtualtour/index.html (http://archive.msichicago.org/exhibit/U505/virtualtour/index.html)
Vesikko: http://www.360cities.net/image/wwii-nazi-submarine-exterior#338.20,0.90,88.3 (http://www.360cities.net/image/wwii-nazi-submarine-exterior#338.20,0.90,88.3)
http://www.kolumbus.fi/mika.ajomaa/Panorama_2.html (http://www.kolumbus.fi/mika.ajomaa/Panorama_2.html)


--
Regards
Maciek


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2012, 03:37
I think you right, I am sure the Germans keep this valve simple. We just need a few more good photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Oct , 2012, 12:26
Tore, how does this look?

(http://img840.imageshack.us/img840/1909/engineroom1.jpg)
(http://img838.imageshack.us/img838/8792/engineroom2.jpg)
(http://img17.imageshack.us/img17/3223/new1la.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Oct , 2012, 13:39
I have no photo's of the base, so this is that I think.

(http://img820.imageshack.us/img820/7218/engineroom3.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2012, 15:24
Simon
Very detailed and high standard. I believe the top nut has a split ( it is a kind of a nut not intergratet in the valvedisc) and that the valvecage boltdown is bit different in order to accommodate the valverocker pedestall. If you look into the main engine page of  u historia you shall find a very good photo of the valvecage and pedestall.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2012, 15:39
Simon further to my last post. The u historia- Technica-Visita Guiada-Sala Diesel-Culata. The Culata photo shows the valvecage with coolingwaterpipes and valvespindle lubeoil pipeconnection and well as the valverockerpedestal (support) very clearly and would for sure help you.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Oct , 2012, 16:52
Tore, I am not 100% sure which nut you are talking about "top nut has a split"

(http://img203.imageshack.us/img203/1909/engineroom1.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 00:46
Simon.
It`s the nut on the top of the valvespindle as indicated on the picture below. May be you should add the lockingwire as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 02:07
Simon further to my last post. The u historia- Technica-Visita Guiada-Sala Diesel-Culata. The Culata photo shows the valvecage with coolingwaterpipes and valvespindle lubeoil pipeconnection and well as the valverockerpedestal (support) very clearly and would for sure help you.
Tore
Simon
Exhaust valve cage
I`m not sure I understand your exhaustcage drawing. Basically the cage looks like the drawing below ( the double spring is not relevant here). On the other photo of a valvecage is only the green part visible protruding out of the cylindercover top and has the coolingwater in and out connection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 02:26
Simon.
It`s the nut on the top of the valvespindle as indicated on the picture below. May be you should add the lockingwire as well.
Tore

Thanks, Tore.

I was able to found one of the nuts and the split makes sense. I will update my drawing in the morning. How wide should the split, about 2-4 mm?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 02:28
Simon.
Further to my  above post, below is a picture of the actual connections on the valvecage.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 02:32
Simon.
It`s the nut on the top of the valvespindle as indicated on the picture below. May be you should add the lockingwire as well.
Tore
Simon
In locked position 2-4 mm would be OK I guess.
Tore

Thanks, Tore.

I was able to found one of the nuts and the split makes sense. I will update my drawing in the morning. How wide should the split, about 2-4 mm?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 02:40
Simon.
Further to my  above post, below is a picture of the actual connections on the valvecage.

Thanks, will be usefull as I am planning to draw this in the morning and was going to ask you about the pipes  ;D

So just checking, the left is the Therm. and the right is a drain line?
(http://img21.imageshack.us/img21/1306/new1zb.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 04:26
Yes Simon, the blue pipe on the picture below is a dearation pipe which shall lead to the funnels seen on you picture  not the open air as on the photo. The outletpipe goes eventually to the common coolingwater discharge pipe from the engine I think outboard side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 12:55
Tore, I found this very small line. I can only found it in this photo and can not found it on any plans.
(http://img27.imageshack.us/img27/9219/new1os.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 12:59
Yes Simon, the blue pipe on the picture below is a dearation pipe which shall lead to the funnels seen on you picture  not the open air as on the photo. The outletpipe goes eventually to the common coolingwater discharge pipe from the engine I think outboard side.
Tore

Tore, does the pipe with the funnels just run into the bilge?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 14:12
Tore, how does this look?

(http://img202.imageshack.us/img202/6448/engineroom1n.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 14:38
Tore, I found this very small line. I can only found it in this photo and can not found it on any plans.
  • What is it for?
  • Is it on each valve cage?
  • Where does the line go?
(http://img27.imageshack.us/img27/9219/new1os.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Simon I assume this is the inlet valvecage (no cooling) in that case the small pipe is probably the lubeoil pipe for the valvespindle and sit on every inletvalve like the previous shown pipe on the exhaustvalve sit on every exhaust valvecage.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 14:46
Yes Simon, the blue pipe on the picture below is a dearation pipe which shall lead to the funnels seen on you picture  not the open air as on the photo. The outletpipe goes eventually to the common coolingwater discharge pipe from the engine I think outboard side.
Tore

Tore, does the pipe with the funnels just run into the bilge?
Yes Simon I believe it end up in the bilge in the aft end bilge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2012, 14:57
Your new valvecages with pipes looks excellent, I believe you shall end up with a extraordinary enginetop.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Nov , 2012, 16:08
Tore, what are these two pipes? Its looks like the left are sensors and go to the overhead gauges.

(http://img715.imageshack.us/img715/9076/new1aj.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 01:58
Simon
Exhaustmanifold.
Below I have indicated the components your inquired. The seacooling water from the engine ends up into the exhaust manifold coolingcasing, with all the bends and pipes, air could easily be trapped causing problems with the coolingsystem, hence the rather extensive deairation, which ends up in a common funnel aft in the engineroom. On the systemsketch below the principle is shown, howewer as you see the practical solution differ slightly from the systemsketch.
 The other item is the wire for remote reading of the exhaust temperature, for each cylinder, hence 6 wires. The 6 analog rectangular meters is very dominating at the manuevering stand.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 03:05
Simon.
Further to my  above post, below is a picture of the actual connections on the valvecage.
Simon
Unfortunately the inlet and outlet of the cooling waterpipes for the exhaust valvecage have been mixed up, below is the correct system, always the temp. reading on the outlet
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 02 Nov , 2012, 07:02
Tore -
I have said it before and I shall undoubtedly say it again... Thank you for providing us with so much intimate knowledge of the KNM Kaura/U-995. She deserves to be remembered, and your understanding of her and willingness to help us is outstanding. This Marine very much appreciates your efforts and hope you are having as much fun with this as we are!
Christopher.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 07:48
Christopher
Good to have you back, I assure you I`m having a great fun , it is almost like living my younger days once more. To some of you it might looks a bit crazy to go into tiny details like lockingnuts and wires, but if you have the overall picture correct, tiny details like this adds spices to the dish and I convinced with Simons drawingskills he ends up with an unsurpassed piece of documentation about the VIIC, an icon from WW2 which still obviously fascinates a lot of people. I love to participate and can`t wait to see the result.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 02 Nov , 2012, 12:37
Tore -
Thank you for the welcome back. In the Northern Hemisphere summers I am rarely indoors, so I have been away from this forum, but I come back. You folks are just too great to leave!
My compliments, of course to Simon and his drawing skills... He has done incredible work and I admire his tenacity and observational skills. As you know, I am working on drawings of a similar nature, but from a different standpoint (and with a different style) for the Bugraum, intending to put as much detail as possible in it. I am working towards the goal of perfecting my drawings and aiming towards making parts for cut-away models like I am prototyping. Hopefully other people can have as much fun as I am with my cut-away project.
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Nov , 2012, 12:45
Tore, I was wondering, would some of the very small pipes, would they be copper?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 13:12
Simon, copper would be the natural material for the pipes however in last part of WW2 copper was hard to get in Germany and it could be they were forced to change to steel on the U boots built after  last part of 1943 and onwards. I really can`t remember but if you look on f.i.  the lubricatorpipes shown on the photos of U 995 ( launched July 22. 1943) it certainly is copper, so I would say copper depending on what model you go for.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 13:27
Tore -
Thank you for the welcome back. In the Northern Hemisphere summers I am rarely indoors, so I have been away from this forum, but I come back. You folks are just too great to leave!
My compliments, of course to Simon and his drawing skills... He has done incredible work and I admire his tenacity and observational skills. As you know, I am working on drawings of a similar nature, but from a different standpoint (and with a different style) for the Bugraum, intending to put as much detail as possible in it. I am working towards the goal of perfecting my drawings and aiming towards making parts for cut-away models like I am prototyping. Hopefully other people can have as much fun as I am with my cut-away project.
Christopher
I am happy to hear you shall continue you unbelievable work and looking forward to seeing the progress Christopher. I`m now back to the civilisation e.g. proper broadband after my annual 6 months summerstay at my farm in the wilderness of the deep forests. So Christopher shoot your questions I love to answer if I can within my capacity.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Nov , 2012, 13:31
Simon, copper would be the natural material for the pipes however in last part of WW2 copper was hard to get in Germany and it could be they were forced to change to steel on the U boots built after  last part of 1943 and onwards. I really can`t remember but if you look on f.i.  the lubricatorpipes shown on the photos of U 995 ( launched July 22. 1943) it certainly is copper, so I would say copper depending on what model you go for.
Tore

Thanks, as my drawing of a late war Type VIIC/41 I will go steel.

Also, I am total loss on the (fuel system ?? - Not sure if it the right name). I have no photo's or drawings of this systems of piping or things between the two rocker arms. I have no idea what to draw :( :( Any help will be very useful.

By the way it just started snowing again  :o

(http://img526.imageshack.us/img526/8284/new1jd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2012, 14:58
Simon, copper would be the natural material for the pipes however in last part of WW2 copper was hard to get in Germany and it could be they were forced to change to steel on the U boots built after  last part of 1943 and onwards. I really can`t remember but if you look on f.i.  the lubricatorpipes shown on the photos of U 995 ( launched July 22. 1943) it certainly is copper, so I would say copper depending on what model you go for.
Tore

Thanks, as my drawing of a late war Type VIIC/41 I will go steel.

Also, I am total loss on the (fuel system ?? - Not sure if it the right name). I have no photo's or drawings of this systems of piping or things between the two rocker arms. I have no idea what to draw :( :( Any help will be very useful.

By the way it just started snowing again  :o

(http://img526.imageshack.us/img526/8284/new1jd.jpg)
Simon, copper would be the natural material for the pipes however in last part of WW2 copper was hard to get in Germany and it could be they were forced to change to steel on the U boots built after  last part of 1943 and onwards. I really can`t remember but if you look on f.i.  the lubricatorpipes shown on the photos of U 995 ( launched July 22. 1943) it certainly is copper, so I would say copper depending on what model you go for.
Tore

Thanks, as my drawing of a late war Type VIIC/41 I will go steel.

Also, I am total loss on the (fuel system ?? - Not sure if it the right name). I have no photo's or drawings of this systems of piping or things between the two rocker arms. I have no idea what to draw :( :( Any help will be very useful.

By the way it just started snowing again  :o

(http://img526.imageshack.us/img526/8284/new1jd.jpg)

Simon, the encircled area on your photo is the startingvalve system. On the picture below I have indicated the relevant parts. The black pipe is fuelsuctionpipe to the supplypump up front of the engine and the indicated HP fuelpipe is the pipe from the HP fuelpump to the fuelinjector in the cylindercover. Ignore these pipes for the time being and consentrate on the startingpipes/valves. The main startingair supplypipe goes all the way from maneuvringstand along the engine and is almost hidden by the black fuelpipe but you see clearly the connectionflanges on each startingvalve. The smaller pipe on top of the airsupplypipe is the startingvalve controlair and run along the engine as well with a branch off to each startingvalve top. When the main airvalve up front is opened, air is entering the startingair supplyline and when the starting handle is put to start, air is admitted to the top of the startingvalve, force a piston down and the starting valverod gets in contact with the camshaft controlling the lifting of the rod and hence opening of the relevant startingvalve. The engine starts running on air and fuel is admitted and engine is running on fuel. Then the handle is put on run position the top chamber of the startingvalve is vented and a spring push the piston and valve rodarm up, the rod goes down and releases the rod roller from the cams and the startvalve is disengaged.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Nov , 2012, 16:17
(http://img607.imageshack.us/img607/1909/engineroom1.jpg)

(http://img822.imageshack.us/img822/3991/new2gy.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2012, 02:11
Simon, your fuelrack drawing is impressive. I have linked it up to the isometric sketch showing details of levers at both end. The parts inside the yellow lines are in the camshaftcasing and not visible, up front are the levers partly visible under the lubricator. I`m not sure how much you want to incorporate in you drawing though.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2012, 02:51
Simon, may be the above picture can be a bit confusing as the photo is showing the fwd linkage. I`ll rectify that with the below picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2012, 08:09
Simon.
I am not sure if your two overhead drawings of the fuelpump/fuelrack is representing port and starboard engine. In case it is, starboard engine pumps are different connected, they are turned 180 degrees  This results that the movement of the fuelrack linkage is opposite that of port engine resulting a different endconnection to the servomotor and fuelhandle. I have indicated below what I try to explain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Nov , 2012, 12:50
Simon.
I am not sure if your two overhead drawings of the fuelpump/fuelrack is representing port and starboard engine. In case it is, starboard engine pumps are different connected, they are turned 180 degrees  This results that the movement of the fuelrack linkage is opposite that of port engine resulting a different endconnection to the servomotor and fuelhandle. I have indicated below what I try to explain.
Tore

 Hi Tore
 
That was a little trickily!! It took me a little bit of time to work that out. It was not a simple 180 ;)

(http://img222.imageshack.us/img222/1909/engineroom1.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2012, 14:20
Yes Simon, but now comes the difficult bit. The stb servomotor is, I presume,  just kept the same as the port ( not turned), but placed on a mirror engine ( stb) of port engine.The rod for the governor comes up in the same position on mirror execution which mean the rod has to be fitted with a linkage to compensate for a displacement. In addition it should move the fuelrack in the opposite direction which means you have to introduce an extra "rockerarm" to reverse the movement. This is starting to be complicated to explain and I have no picture to show. I suggest you look at the Kubische Panorama to see the difference between port and stb and may be you have other pictures of the detail.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2012, 14:55
Simon
I made two very bad photos of port and starboard linkdifferences for the servo/fuelrack linkages just to show you what to look for.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2012, 01:27
Simon.
I am not sure if your two overhead drawings of the fuelpump/fuelrack is representing port and starboard engine. In case it is, starboard engine pumps are different connected, they are turned 180 degrees  This results that the movement of the fuelrack linkage is opposite that of port engine resulting a different endconnection to the servomotor and fuelhandle. I have indicated below what I try to explain.
Tore

 Hi Tore
 
That was a little trickily!! It took me a little bit of time to work that out. It was not a simple 180 ;)

(http://img222.imageshack.us/img222/1909/engineroom1.jpg)
Simon, I wonder why you have displaced the HP fuelpumps on stb engine  in relation to the port. Basically the centerline for the cylinders are the same and placed right opposite to  each engine. So each fuelpump is directly on the same spot on port and stb engine. The change of the fuelrack between cylinder 3 and 4 is simply a production necessity. The two engineblocks are just  flanged  together right here. The flange make it necessary to move the fuelrack pedestal to another position, hence the fuelrack coupling for cyl. 4 and 5. Se my pictures.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Nov , 2012, 10:51
Hi Tore

When I started updating the starboard fuel pumps the other day, it seen worng. So I take a second look at the starboard engine using Kubische Panoramen, and noted the offset of the fuel pumps. From the photo below you can see the offset of the fuel pumps.

Port fuel pump is forward of the rod & starboard fuel pump is aft of the rod.
(http://img7.imageshack.us/img7/3498/new2vpl.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2012, 12:05
Simon I had the same impression but from an enginering point I couldnt`t believe what I saw. After checking I have come to the conclusion it must be an optical illusion. I cannot se any reason for such an arrangement which would involved another camshaft or place the stb engine a bit forward of the port. I am almost 100% sure the cylindercenterlines on both engines are in line.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Nov , 2012, 12:23
Tore, I believe you right the cylinder are center lines, but I believe the fuel pumps are offset for so unknown reasons.

If you look at two rods (number 5 & 6 - Marked on the photo), the port fuel pump is right next to no. 5 rod. On the starboard side the fuel pump is right next to no. 6 rod. You can see the gap I have mark on the photo.

(http://img17.imageshack.us/img17/5550/new2an.jpg)

(http://MiG442.imageshack.us/MiG442/6936/new2AL.jog)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2012, 13:39
Tore, I believe you right the cylinder are center lines, but I believe the fuel pumps are offset for so unknown reasons.

If you look at two rods (number 5 & 6 - Marked on the photo), the port fuel pump is right next to no. 5 rod. On the starboard side the fuel pump is right next to no. 6 rod. You can see the gap I have mark on the photo.

(http://img17.imageshack.us/img17/5550/new2an.jpg)


(http://MiG442.imageshack.us/MiG442/6936/new2AL.jog)
Simon I think I have found an explanation. The cylinder centerlines are matching on port and stb engine , the are not displaced in relation to each other. The camshaft is the same on both engines but turned 180 degrees on stb in relation to port, this can be done because port and stb engine have opposite revs direction. The registerdrive have to be fitted on the otherside of the stb camshaft though.  The cylindercovers and crankshaft are turned 180 degrees as well which means the the valves ( except the center placed fuel injectionvalve) change place so on stb the exhaustvalves are forward and on port aft. The startingvalves are forward on stb and aft on port engine.This fit excellent with the camshaft. On the crankshaft the registerdrive ,and vibrationdamper have change place.This is a much cheaper way of building mirror execution engines. On you drawing the visualeffects would be positions of the startingvalves with rods, exhaustvalves with cooling waterpipes , thermometers and lubricatorpipes, inletvalves with lubricatorpipes. if you look at the Kubische Panoramen picture you can clearly see this. On starboard engine the rod for the startingvalve is forward of the HP fuelpump, on port aft. If you check on the top you no doubt would see the different places of the inlet and exhaustvalves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2012, 14:18
As an additional information you will see the indicator cocks are aft of the HP fuelpumps on port engine and fwd on the starboard. This means that the HP fuelpumps are placed in the centerline as the fuelinjetorvalves are, so I believe no displacement for these items.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Nov , 2012, 14:28
Hi Tore

Thanks for the information. But it did show my short coming in machinery knowledge :( I follow must of it, but a bit was over my head ;D

Below, I did a very basic overhead layout on what I understood from the last posts, does this seen correct? Starting to get a little confuse ::)

(http://img109.imageshack.us/img109/1909/engineroom1.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2012, 15:04
Simon
Sorry sometimes I get carried away. The main thing is that you get the visual facts so your pictures are as correct as possible. It is always  a reason for things are like they are and sometimes when you understand the reason it is easier (for me at least) to get things correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Nov , 2012, 15:35
Hi Tore

No worry, I always like lots of information!

I had again look and I noted the exhaust (dark blue) is forward on each cylinder head, not like my previous drawing.

(http://img196.imageshack.us/img196/8792/engineroom2.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Nov , 2012, 15:54
Hi Tore

As I have no photo's of the starting valve system, it extremely hard to get a accurate drawing, so I am drawing the cross-section to help me in the other views. How does this look below? I am still adding detail to the drawing.
 
Thanks, Simon.

(http://img3.imageshack.us/img3/159/new1jr.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 00:23
Simon not bad. The rocker arm, indicated in black, goes to the other side of the fulcrum, just like the exhaust/inletvalve rocker arms. The valve rockerarms engages the valvespindle in a slot. I am in doubt about the valve you have placed on the control airpipe to the top of the valve, do you have a picture of that? Below on my picture I have tried to explain a bit more on the details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 01:04
Simon judging from your last posted picture I got the impression that my post yesterday was a bit confusing. I`m posting your photo where I have indicated what I mean to say.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2012, 01:07
I am in doubt about the valve you have placed on the control airpipe to the top of the valve, do you have a picture of that?

(http://img89.imageshack.us/img89/1148/new1gbvg.jpg)
(http://img854.imageshack.us/img854/1366/new2sx.jpg)
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 01:34
Simon
I guess it is OK!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 08:46
Hi Tore

As I have no photo's of the starting valve system, it extremely hard to get a accurate drawing, so I am drawing the cross-section to help me in the other views. How does this look below? I am still adding detail to the drawing.
 
Thanks, Simon.


(http://img3.imageshack.us/img3/159/new1jr.jpg)
Simon, the crossection drawing behind your startingvalve drawing is one of the best I have seen so far. Do you have a full section? That could help a lot in explaining the various components
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2012, 10:44
Hi Tore

Here a original German photo that show the valve on U-564, also very interesting is you can see that the have painted the inside of the rocker arm.

(http://img850.imageshack.us/img850/536/new2j.jpg)
(source: U-boat War Patrol - The Hidden Photographic Diary of U564 By Paterson, Lawrence)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 11:58
Simon.
Painting of the engines did not`t have a navy code and was for us anyhow something which was up to the engineers, sometimes overruled in extreme cases by the chief engineer. One rule however, moving machined parts,springs, shafts,handles etc was always kept shiny metallic. Painting inside the valve rockerarms would be OK particularly if you have a metallic rim as seen on the picture. On Laboe U 995 painting is far overdone and moving parts are painted to such an extent that they look like they are  casted (intgrated) to F.I. a fulcrum.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2012, 12:11
I imagine on a long patrol at sea, someone in the engine room got bore and decided to full a few days painting things  ;D ;D

(http://img211.imageshack.us/img211/8363/new1l.jpg)
Added a little bit more detail. Tore, how does the new parts look ok?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 12:30
Yes Simon I have experienced that more than once. We had one guy once who painted all the nuts on the engine red. It looked horrible and we came to the conclusion the engine got the measels. I revert in a minute as to your new details on the cylindercover.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 13:04
Simon , I am still puzzled about you sort of half rocker arm (the black outline). This is a full rockerarm ( yellow) and gets in contact with the valvespindle and lower it so the startingvalve opens. Se my picture below. Otherwise everything looks nice.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2012, 13:30
Hi Tore.
 
No need to be puzzled about the half drawn rocker arm as I only did this drawing to help me with my
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 13:44
Simon. Great very interesting to see how you do it! :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2012, 14:40
Tore, this is the best I can currently do with the starting valve system with the photo's & plans I have. I am sure there are missing details but that will have to wait to till we get more information.

(http://img855.imageshack.us/img855/8792/engineroom2.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2012, 15:04
Simon. It is definitely getting better! When the reminding items get into place it shall be cramped.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2012, 02:08
Simon.
Cylindercover bolt/nuts
The arrangement and look of the cylindercover bolts and nuts migth be a bit confusing. The cyl. covers are bolted to the cyl. block by 8 bolts symmetrically placed as the yellow dots on drawing below. The confusing part is that you don`t see the two inboard nuts marked purple on the drawing. I guess they are placed in recesses under the exhaust/inletvalve rocker pedestals. The reason would be that these studs don`t go all the way to the covertop as they would obstruct the dismantling of the cover. Sleevenuts would be used to reach the shorter studs in the recesses and the top of the nuts shall be flush with the cyl. cover I guess. Anyhow, for your drawing it means, I believe, the yellow nuts are the only to be visible.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2012, 05:33
Simon
In addition to my last post the overhead drawing of the enginetop shows large circular objects between the cyl. covers inboard side. The engine is built up of caststeel pieces, the majors being the crankcase and the cylinderblocks. They are bolted together by mean of long tiebolts with nuts on the lower parts ( in the crankcase) and heads on top of the cyl. block. There are alltogether 14 tiebolts 7 inboard and 7 outboard, on the drawing 7 inboard and 1 outboard are visible. In order not to obstruct the fitting of the cylindercovers, the heads of the tierods are fitted in  recesses in the cylinderblock, the recesses are covered by  steelplates and that is the circles you see on the overhead drawing. By the way, putting the inboard cylindercover studs ( the short ones) in  recesses makes it possible to accommodate the rockerarm pedestals on the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2012, 08:32
Final?  The details of cyl cover top. One item remains to be identified, the safetyvalve, which is a pressure reliefvalve and you can barely see the top protruding out of the cylindercover top. The place is indicated below.
The cooling watercock looks a bit strange, but it is because the function is you can lead the water out from the cylinderblock cooling either fully through the exhaustvalve (series) or partly ( parallel) depending upon the need.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2012, 13:01
Simon.
Cylindercover bolt/nuts
The arrangement and look of the cylindercover bolts and nuts migth be a bit confusing. The cyl. covers are bolted to the cyl. block by 8 bolts symmetrically placed as the yellow dots on drawing below. The confusing part is that you don`t see the two inboard nuts marked purple on the drawing. I guess they are placed in recesses under the exhaust/inletvalve rocker pedestals. The reason would be that these studs don`t go all the way to the covertop as they would obstruct the dismantling of the cover. Sleevenuts would be used to reach the shorter studs in the recesses and the top of the nuts shall be flush with the cyl. cover I guess. Anyhow, for your drawing it means, I believe, the yellow nuts are the only to be visible.
Tore

Hi Tore
 
This is fantastic! I do not realize that were was eight cylinder cover bolt/nuts. This is the detail I love ;D I have updated both my drawings (top and side views). Below are the updated drawings, it a little hard to see all the cylinder cover bolt/nuts.
 
Thanks, Simon.

(http://img542.imageshack.us/img542/2968/nutsx.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2012, 13:57
Simon. Excellent, this is going to be the best ( except for the design drawings) drawing of the GW M6V 40/46 engine made ever. A small detail, check the diameter of the HP fuelpipe in relation to the airpipes, particularly the controlair branch to the top of the startingair valve. It seems to me the fuelpipe is slightly too large or more probable the airpipes slightly too small.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2012, 14:37
Simon, another small detail. It seems to me that you have made the fuelsupply pipe to the HP fuelpipe of copper, I believe it is of steel. The Laboe U 995 get a funny rusty look on the unpainted steelparts, see picture below where the steelhandles colour is identical to the fuel supplypipe whereas the real copperpipe has a different colour
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2012, 15:12
Simon
In addition to my last post the overhead drawing of the enginetop shows large circular objects between the cyl. covers inboard side. The engine is built up of caststeel pieces, the majors being the crankcase and the cylinderblocks. They are bolted together by mean of long tiebolts with nuts on the lower parts ( in the crankcase) and heads on top of the cyl. block. There are alltogether 14 tiebolts 7 inboard and 7 outboard, on the drawing 7 inboard and 1 outboard are visible. In order not to obstruct the fitting of the cylindercovers, the heads of the tierods are fitted in  recesses in the cylinderblock, the recesses are covered by  steelplates and that is the circles you see on the overhead drawing. By the way, putting the inboard cylindercover studs ( the short ones) in  recesses makes it possible to accommodate the rockerarm pedestals on the top.
Tore

Hi Tore :)

Again big thanks! I was going to ask you in a few days what this was on the engines. I have added the Tie bolts to my drawings. I also noted that I had missed them from the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2012, 15:17
Simon, another small detail. It seems to me that you have made the fuelsupply pipe to the HP fuelpipe of copper, I believe it is of steel. The Laboe U 995 get a funny rusty look on the unpainted steelparts, see picture below where the steelhandles colour is identical to the fuel supplypipe whereas the real copperpipe has a different colour
Tore

Tore, thanks. I realise they are steel just have not found the time to change the colour yet. On the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2012, 17:45
Final?  The details of cyl cover top. One item remains to be identified, the safetyvalve, which is a pressure reliefvalve and you can barely see the top protruding out of the cylindercover top. The place is indicated below.
The cooling watercock looks a bit strange, but it is because the function is you can lead the water out from the cylinderblock cooling either fully through the exhaustvalve (series) or partly ( parallel) depending upon the need.
Tore

Hi Tore :)

Thanks! I was going to ask you this question also ;D Again added the new sub-system to my drawings.

(http://img163.imageshack.us/img163/8792/engineroom2.jpg)
(http://img841.imageshack.us/img841/9143/new1hq.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2012, 20:42
Simon. Excellent, this is going to be the best ( except for the design drawings) drawing of the GW M6V 40/46 engine made ever. A small detail, check the diameter of the HP fuelpipe in relation to the airpipes, particularly the controlair branch to the top of the startingair valve. It seems to me the fuelpipe is slightly too large or more probable the airpipes slightly too small.
Tore

Hi Tore
 
I am almost sure I know what pipes you are talking about, if so I also noted this and made the changes on the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2012, 01:49
Simon. We are almost there I believe. Something with the drawing projection is a bit strange to me. You obviously are basing your first drawings on port  engine aft. The topview of the cover is  placing the valverods outboard, to me this is a different way of projecting. In order to prevent any misunderstanding I post a drawing to explain what I mean.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2012, 02:03
Simon. By the way I guess I somewhere mentioned that the inlet and exhaustvalves were turned 180 degrees, I have to correct that. The exhaustvalves are forward of the inlet valves on both engines. See picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2012, 05:44
Simon.
Pipedimensions.
May be a closer look into the starting airpipe branch off to the top of the startingvalve, and the main starting air supply pipe in relation to the HP fuelpipe would be worth while. See picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Nov , 2012, 01:00
Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Nov , 2012, 06:23
Simon.
Cyl cover- exhaustvalve piping.
Below is a picture showing my proposal of the piping, it might be the cockarrangement is different. This would be starboard engine, forward to the right. The cockhandle is on the other side of the cock and the ventingpipe ( blue ) is missing I believe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Nov , 2012, 08:45
Simon.
Fuel supply pipe to HP pumps.
On your drawing it seems that somehow the collecting drain pipe is connected both to the lubeoil drain pipe from the governor servomotor and the fuel supply pipe to the HP fuelpumps. The collecting drainpipe runs along the engine about where the cylindercovers meets the cylinderblock and collect drain from each cylindercover via funnels. I guess it possibly ends up in the dirty lubeoil tank underneath the floorplates. Anyhow this relatively simple drainpipe has nothing to do with the other two systems. See drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Nov , 2012, 16:20
Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

(http://img22.imageshack.us/img22/1286/new1yrk.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 01:20
Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

(http://img22.imageshack.us/img22/1286/new1yrk.jpg)
Simon.
This is a bit hard to be 100% sure about. Below I have tried to clarify by putting a mirror picture of stb engine next to the your picture of port engine. As you see it is a venting cock right where the pipebranch to the common venting pipe should be and on the other side of the cooling bend is the pipebranch to the common ventpipe.
The only explanation I can give is that the common venting pipe has a shut of valve somewhere at the other end and that the extra ventingcock is a the end of the exhaustmanifold where air is likely to be trapped. By having the venting on this strategic place you can avoid to open up for all the venting which means a lot of water in the bilge. Anyhow I don`t think the end of the handle shown on your photo has anything to do with this, but is a handle placed on the opposite side of the series/parallel exhaustvalve cooling cock. For some reason not equipped with heat insulation handle.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 01:33
Simon
Just a small correction to my picture I see I have marked the main startingair pipe as a starting air valve, sorry.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Nov , 2012, 01:59
Simon.
Cylindercover cooling.
I realize we haven`t gone into details on this subject. The coolingwater enter the cylindercover via pipebends from the cylinder coolingjackets.  The pipebends would the only visible part ( if at all). Out of the cover it enters the series/parallel coolingwater cock ( blue) which allow the water to go to the exhaustvalve cage, either partly (parallel) or all (series) depending upon the temperate reading on the thermometer, it is manually controlled.
The water from the cock then goes to the exhaust manifold coolingspace. The funny looking "spring" on the photo is, I believe, the handle for the cock, the springshape is a typical 1920/30 solution for heat insulation. The details to be seen are a bit unclear to me on this.
Tore

Hi Tore

I am trying to sort out this handle. In the photo below you can see a handle on the exhaust outlet between the flange and the water cooling pipe. Do you think this is the same 'spring shape' handle you are talking about?

(http://img22.imageshack.us/img22/1286/new1yrk.jpg)

Anyhow I don`t think the end of the handle shown on your photo has anything to do with this, but is a handle placed on the opposite side of the series/parallel exhaustvalve cooling cock. For some reason not equipped with heat insulation handle


I now see that you are talking about, and I think you are right. Below is a better view of the series/parallel exhaust valve, you can see where this handle would attach to. Also you can see the other handle better.

(http://img19.imageshack.us/img19/2269/new1ei.jpg)

PS. Made a lot of changes to my drawing today, listed below. Will post pictures in the morning, off to bed now :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 07:21
Simon.
Looking forward to seeing your new drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 07:37
Simon.
Insulated handle.
I `m still not 100% sure about the purpose of this cock. Being a cooling water cock/vent it shouldn`t be necessary to have such a heat insulated handle, it would be more likely for an exhaustcock. But right now I cannot remember or see the use for exhaust cocks on each inlet to the exhaust manifold as you have exhaust thermometer pockets. You probably should just draw it, if I get ideas I`ll let you know. Below is a picture I made of the handle in case you are not familiar with the design.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Nov , 2012, 12:17
Hi Tore

I know that purple is the safety valve, but what is green?

(http://img689.imageshack.us/img689/3831/new1dj.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 13:50
Simon.
A very good question. The green arrow point to the safetyvalve, if you see the drawing below, the startingvalve, fuelvalve and safetyvalve are placed on the centerline in the cross section drawing, which put a new question forward what`s in the place were we put the safetyvalve in the beginning? If you look at the drawing nothing protrude out of the cylinder covertop, and the object is outside the combustion space, e.g. cylinder. I`m inclined to believe this might be a cover for a castingcore opening in the cylindercover coolingspace. So I guess you can put the safetyvalve in the centerline and just indicate a cover where we erroneously placed the safetyvalve in the beginning.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2012, 14:14
Simon.
Another idea struck me, probably more correct. The cylindercovers are the same on both engines but turned 180 degrees on the other engine. The watercooled exhaustvalves are forward of the inletvalves on both engines. Everything  which are in the centerline are OK and need not to be changed. The exhaust valvecasing and the inlet valvecasing are identical and fit in both valverecesses in the cover.When the covers for the other engine are turned 180 degrees the only extra opening in the cover has to be the coolingwater opening for the exhaustvalve casing and that matches exactly. The  plate in the cylindercover is the cover for the extra coolingwater connection to the exhaustvalve cage to be used when the cyl. cover is turned.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Nov , 2012, 23:26
Simon.
A very good question. The green arrow point to the safetyvalve, if you see the drawing below, the startingvalve, fuelvalve and safetyvalve are placed on the centerline in the cross section drawing, which put a new question forward what`s in the place were we put the safetyvalve in the beginning? If you look at the drawing nothing protrude out of the cylinder covertop, and the object is outside the combustion space, e.g. cylinder. I`m inclined to believe this might be a cover for a castingcore opening in the cylindercover coolingspace. So I guess you can put the safetyvalve in the centerline and just indicate a cover where we erroneously placed the safetyvalve in the beginning.
Tore

Hi Tore

When I was adding the safety valve to the drawing I thought it was centre line. I will update my drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Nov , 2012, 00:08
Simon very good. I`m absolutely sure my last theory is correct. The superfluous opening in the cylindercover is for the exhaustvalve cooling if the cover is placed on the other engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Nov , 2012, 01:55
Simon.
Studying you last drawing I`m not sure about the placing  of the cock with the springhandle. I assume the drawing is stb aft. If you look at my drawing below I believe the
 cocks are placed aft of the coolingbends. On the aft cylinder the springhandle is missing. May be you drawing isn`t updated yet.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2012, 07:41
Direct reversible engine.
In all descriptions on the dieselengines of the VIIc (GW and MAN) a direct reversible system is mentioned. On the drawings of the diesel a large cylinder is shown outboard next to the maneuvering stand, this is the reversing cylinder. On some photos the reversing cylinder can be seen. The most common way of maneuvering a submarine is by E-motors, in the RN and many other navies. On photos of the  on the U 995 engines you don`t see the reversing cylinder because the engines were not direct reversible, neither were the U 926 and U 1203 and these submarines were maneuvering by E-motors. My idea Simon is that all the newer VIIc diesel engines were not direct reversible and you should ignore this device on you U 1308 drawings. Below is a picture showing what I`m trying to say.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 11:05
Simon.
A very good question. The green arrow point to the safetyvalve, if you see the drawing below, the startingvalve, fuelvalve and safetyvalve are placed on the centerline in the cross section drawing, which put a new question forward what`s in the place were we put the safetyvalve in the beginning? If you look at the drawing nothing protrude out of the cylinder covertop, and the object is outside the combustion space, e.g. cylinder. I`m inclined to believe this might be a cover for a castingcore opening in the cylindercover coolingspace. So I guess you can put the safetyvalve in the centerline and just indicate a cover where we erroneously placed the safetyvalve in the beginning.
Tore

Fixed and updated :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 11:10
Simon.
Another idea struck me, probably more correct. The cylindercovers are the same on both engines but turned 180 degrees on the other engine. The watercooled exhaustvalves are forward of the inletvalves on both engines. Everything  which are in the centerline are OK and need not to be changed. The exhaust valvecasing and the inlet valvecasing are identical and fit in both valverecesses in the cover.When the covers for the other engine are turned 180 degrees the only extra opening in the cover has to be the coolingwater opening for the exhaustvalve casing and that matches exactly. The  plate in the cylindercover is the cover for the extra coolingwater connection to the exhaustvalve cage to be used when the cyl. cover is turned.
Tore

Fixed and updated :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 11:15
Simon.
Cyl cover- exhaustvalve piping.
Below is a picture showing my proposal of the piping, it might be the cockarrangement is different. This would be starboard engine, forward to the right. The cockhandle is on the other side of the cock and the ventingpipe ( blue ) is missing I believe.
Tore

Fixed and updated  :) :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2012, 11:58
You have been busy,I bet by now your drawing would give a very interesting top view look, in fact as accurate and a standard never seen before. But a lot remains to be done on the other sides of the engine,piping,airduct,supercharger, maneuvringstand exhaust ducts with pneumatic valvegrinder etc. A lot of fun ahead.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 11:59
Hi Tore

Can you remember how the rocker arm base was attached to the head? I can see one large bolt in the front, are there any other bolts holding it down?

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2012, 13:05
Hi Tore

Can you remember how the rocker arm base was attached to the head? I can see one large bolt in the front, are there any other bolts holding it down?

Thanks, Simon.
Simon. As previously said the rocker arm pedestal sit on the top of the recess for the inboard cylindercover short studs so no fixingstuds can be place there. On the top of the cover is an "ear" protruding inboard and outside the cover. In this ear is a hole for the rocker pedestal basestud of some 20-25mm I believe. You can clearly see the "ear" with hole underneath on Kubische Panorama. On the other side probably a little closer to the pedestal centerline you got to have a similar stud, but that is a bit hard to be seen. Don`t be fooled by the small nuts for the guide positionscrews clearly to be seen. It might be there is a better quality overheadsketch somewhere to be seen.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 13:08
Hi Tore

While updating the drawing this morning, I noted that I had this rocker arm the wrong way around for the starboard side :( Correct layout below.

(http://img818.imageshack.us/img818/8792/engineroom2.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 13:17
Hi Tore

Can you remember how the rocker arm base was attached to the head? I can see one large bolt in the front, are there any other bolts holding it down?

Thanks, Simon.

Simon. As previously said the rocker arm pedestal sit on the top of the recess for the inboard cylindercover short studs so no fixingstuds can be place there. On the top of the cover is an "ear" protruding inboard and outside the cover. In this ear is a hole for the rocker pedestal basestud of some 20-25mm I believe. You can clearly see the "ear" with hole underneath on Kubische Panorama. On the other side probably a little closer to the pedestal centerline you got to have a similar stud, but that is a bit hard to be seen. Don`t be fooled by the small nuts for the guide positionscrews clearly to be seen. It might be there is a better quality overheadsketch somewhere to be seen.
Tore

Thanks, Tore.

I can see the outer bolt (purple), it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2012, 13:55
Hi Tore

While updating the drawing this morning, I noted that I had this rocker arm the wrong way around for the starboard side :( Correct layout below.

(http://img818.imageshack.us/img818/8792/engineroom2.jpg)
Yes Simon.
For each stb cylinder on camshaftside from aft to fwd: inletvalve rod, HP fuelpump,starting rod, indicatorcock, fuelsupply bend to HP fuelpump and exhaustvalve rod.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2012, 14:38
Simon two more pictures unfortunately of the same thing, I can`t see the other stud. I`ll sleep on it may be I get some idea tomorrow morning.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 15:26
Hi Tore

A couple of questions about the exhaust.
Thanks, Simon.

(http://img43.imageshack.us/img43/4258/new5pl.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Nov , 2012, 19:09
Hi Tore

Found a small error on the exhaust flange which I have fixed this afternoon. Also no drawing tomorrow as I am off to work tomorrow, will post a big update on my drawing very soon.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Nov , 2012, 00:49
Hi Tore

A couple of questions about the exhaust.
  • What is the flange in the middle of the main exhaust pipe for?
  • Why is there a small pipe that link between the two bigger exhaust pipes?
Thanks, Simon.

(http://img43.imageshack.us/img43/4258/new5pl.jpg)
Simon.
The exhaustmanifold is a fairly complicated doublewall ( allowing for the coolingspace ) cast piece. It is split into two parts as the cylinderblock, and bolted together by a flange in the middle. The coolingwater from the two parts is blocked by the flange and has to be bypassed by the coolingwater bend.
At the fwd end of the exhaustmanifold is a reliefvalve and a pipeflange which  is the pipe connection to the suctionside of the coolingwater pump  allowing warm water return to the system. See drawing. Don`t take the system sketch as drawn it`s merely a principle rather than a workingdrawing as you see.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Nov , 2012, 02:36
Hi Tore


I have got some off-topic question. I know, that on KNM Kaura were some electric power points (outlets), which were connected to the boat's electric network (lightning circuit, which was powered by 110 V - despite of battery output voltage changes - by means of automatic voltage regulator). What kind of equipment could be connected to these outlets?


And one more question - do you remember, what kind of electronic device is it? It is located in the forward part of control room, at port site.
(http://img402.imageshack.us/img402/166/u995029.jpg)


Is it German, war-time? Was it installed, when U-995 served in Norwegian Navy?


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Nov , 2012, 04:53
Hi Tore


I have got some off-topic question. I know, that on KNM Kaura were some electric power points (outlets), which were connected to the boat's electric network (lightning circuit, which was powered by 110 V - despite of battery output voltage changes - by means of automatic voltage regulator). What kind of equipment could be connected to these outlets?


And one more question - do you remember, what kind of electronic device is it? It is located in the forward part of control room, at port site.
(http://img402.imageshack.us/img402/166/u995029.jpg)


Is it German, war-time? Was it installed, when U-995 served in Norwegian Navy?


--
Thanks, regards
Maciek



Hi Maciek
I`m not sure I understand you question 100%. If you mean outlet in living quarters, we had very few. Some could be used for transportable lamps but really no uncontrolled electric consumption occurred. We did not have any personal electric devices in those days. I t might be that later somebody installed outlets for waterheater and charging of electric razors. The only outlet we installed in my time was bulbs in the cabinets for protecting our best uniforms to go mouldy. I do not believe the germans originally had many outlet for personal use.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Nov , 2012, 05:06
Maciek
Electronics in the control room. I`m a bit out of my field right now, but I believe the electronic stack next to the navigation table contains mainly the S- geraet (Sondergeraet fuer Aktive Schallortung ) active Sonar and KBD (Kristall Drehbasisgeraet) passive turnable crystal hydrophones which is passive Sonar. The equipment was indeed very much used by us as originally installed. Later however I  believe they installed the  Balcon Geraet which probably would required another electronic stack.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Nov , 2012, 08:39
I`m not sure I understand you question 100%. If you mean outlet in living quarters, we had very few. Some could be used for transportable lamps but really no uncontrolled electric consumption occurred. We did not have any personal electric devices in those days. I t might be that later somebody installed outlets for waterheater and charging of electric razors. The only outlet we installed in my time was bulbs in the cabinets for protecting our best uniforms to go mouldy. I do not believe the germans originally had many outlet for personal use.
Well, this is what I wanted to know. I was wondering, if other devices (other than lamps and ie electric heaters) were in use - for example electrically power tools (I know, there were pneumatic driven, but this is example). What kind of outlets were they? Domestic type (with some water protection)?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Nov , 2012, 10:08
Hi Maciek.
I cannot remember we had any electric power tools except for a drill, I guess they were splashproof very much domestic types, but that could be norwegian installed, hard to say though as we use DIN standard as well. We used sometimes pneumatic tools. Otherwise I really cannot remember we used the few outlets very much.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Nov , 2012, 08:38
Tore,
Electronics in the control room. I`m a bit out of my field right now, but I believe the electronic stack next to the navigation table contains mainly the S- geraet (Sondergeraet fuer Aktive Schallortung ) active Sonar and KBD (Kristall Drehbasisgeraet) passive turnable crystal hydrophones which is passive Sonar. The equipment was indeed very much used by us as originally installed. Later however I  believe they installed the  Balcon Geraet which probably would required another electronic stack.


It's interesting. So on board of KNM Kaura were installed both S-Ger
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 09:04
Simon.
I don`t know how many details your next drawing would incorporate but trying to be a bit ahead I wonder if you have noticed the small cylinder between ME Cylinder 1 and 2. It looks almost like a HP fuelpump and is difficult to see. The cylinder is placed on a driptray on top of the camshaft casing having drainagepipe and on top of the cylinder is a handle. Unfortunately you don`t see any pipeconnection. I cannot say I remember this item but I believe it is a so called knifefilter for fueloil supply. The handle on the top is a handle for a brush inside the filter turning the handle cleans the filter. The reason for this extra filter in addition to the dual filters next to the fuel supplypump at the manoeuvring stand would be if the fuelsupply pump should fail you can by means of the threeway cocks at the stand, shortcut the system ( including the dual filter) and take
the fuelsupply from the daytank by gravity and you would need an extra filter in the supplyline to the HP pumps. I guess we shall get into that when your drawing comes to the the pipesystem. Anyhow just an info prior to you complete your present drawing. Below some photos trying to show these filters.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 09:13
In addition to the above. Unfortunately there are no correct drawings of the pipings on the engines, the systemdrawings keep showing the fuelsupply pump is driven from the camshaft drive aft wheraes the pump is driven from the crankshaft fwd.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 09:54
Tore,
Electronics in the control room. I`m a bit out of my field right now, but I believe the electronic stack next to the navigation table contains mainly the S- geraet (Sondergeraet fuer Aktive Schallortung ) active Sonar and KBD (Kristall Drehbasisgeraet) passive turnable crystal hydrophones which is passive Sonar. The equipment was indeed very much used by us as originally installed. Later however I  believe they installed the  Balcon Geraet which probably would required another electronic stack.


It's interesting. So on board of KNM Kaura were installed both S-Ger
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Nov , 2012, 11:23
Tore
As I said in the beginning this is a bit out of my field so you have to take the info with a pinch of salt. I thought we had both but for sure we had KBD. The balkongeraet was installed after my time so after 1956. I am a posting a picture of KNM Kauras bow and showing how the relevant area looked like in my time.
Thanks for your answer. On the photo you have posted, I think I can see the sender/receiver panel of S-Ger
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 11:35

Maciek.
As I said in the beginning this is a bit out of my field so you have to take the info with a pinch of salt. I thought we had both but for sure we had KBD. The balkongeraet was installed after my time so after 1956. I am a posting a picture of KNM Kauras bow and showing how the relevant area looked like in my time.


Hi Tore
 
Over the last year I have completely change my mind about the balkongeraet on U-995/KNM Kauras. I believe you are right and that U-995 never had that pictured balkongeraet, there now more and more evidence to support this. I have been collection a little information on this and I want to write this up after Christmas.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 11:51
Hi Tore

In the drawing below you can see a smaller circle within the exhaust piping, do you think is could be the pipe for the cooling water?
(http://img687.imageshack.us/img687/9228/new1ie.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 12:08
Simon I doubt this is the flange for the coolingwater it is too large and I presume we see the stb engine towards aft at the manifoldflange which is towards the exhaust manifold outlet end. I`ll see if can figure out what it could be.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 12:22
Simon I doubt this is the flange for the coolingwater it is too large and I presume we see the stb engine towards aft at the manifoldflange which is towards the exhaust manifold outlet end. I`ll see if can figure out what it could be.
Tore

Tore, I was more thinking about the smaller circle being the cooling water pipe that run inside the exhaust pipe.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 12:58
Simon.
I believe the cooling waterbends passes the flanges as shown on the drawings  below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 13:11
Simon, as you see the casting of the exhaustmanifold is in such a way that the same pieces can be used for both stb and port engine, leaving a coolingwater flange at the fwd end. On the photo of the fwd end you see a pipe connected to this flange which I presume is a drain may be to the suction of the cooling waterpump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 14:13
Tore, I am trying to work out where the cooling water goes. Does the used cooling water exit the pressure hull via the exhaust coupling and then vents somewhere under the deck?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 14:20
Hopefully this picture below makes it a bit clearer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 14:49
Simon. The seacooling water diagram explain pretty much how it is done. Same principle as before , at every flange a cooling waterbend leads the water to the next coolingwater space. Where the main exhaust pipe passes the pressurehull you have the main exhaustvalve ( with the grinder) the whole valve casing with coolingspace enter through the hull. You have a pretty good picture of the section at U Historia.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Nov , 2012, 15:12
Simon.
Outboard coolingwater.
As can be seen from the below sketch the coolingwater enters the silencer outside the pressure hull and from there to the coolingwater headertank in the tower.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 15:16
Thanks Tore for the help. I had to check the alignment of my drawing. For example I just can not add my engine drawing to my U-boat drawing as I have to make sure that pipes align correctly, bolts holes match and under decking pipes align correctly to above deck.

Below in the two drawings you can see I had to align correctly the engine frame bolts hole and the cooling water piping

Fig. 1. U-Boat framing.
(http://img805.imageshack.us/img805/3687/new2ac.jpg)
Fig. 2. U-Boat Engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Nov , 2012, 15:25
PS. Another example of alignments, in the drawings above is the open pipe flange for the Engine lubricating oil system. This pipe is currently out of alignment by about 30 mm at 1:1 scale so the two flanges will not match. You will never see is in the drawing as it under the engine but is hated to see oil leaking out of U-1308 ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2012, 00:40
Simon.
Very interesting to see how it is done, it`s a big jigsawpuzzle. Seeing you drawing I assume the black rectangle toward the pressurehull is the airduct from the main engineroom airintake valve. To me it looks as if it is one frame too far forward, see my drawing below. The reason for such a duct was that in bad weather seawater filled the airduct via the main intakevalve in the towercasing and water gushed into the engineroom, you didn`t want that water into the ventilation system so it was lead down into the bilge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Nov , 2012, 01:35
Simon.
Very interesting to see how it is done, it`s a big jigsawpuzzle. Seeing you drawing I assume the black rectangle toward the pressurehull is the airduct from the main engineroom airintake valve. To me it looks as if it is one frame too far forward, see my drawing below. The reason for such a duct was that in bad weather seawater filled the airduct via the main intakevalve in the towercasing and water gushed into the engineroom, you didn`t want that water into the ventilation system so it was lead down into the bilge.
Tore

Hi Tore

I just double check, and I have the air duct in the correct position.

Here today drawing, still lots to do ;)

(http://img585.imageshack.us/img585/8792/engineroom2.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Nov , 2012, 01:40
Simon


I have been collection a little information on this and I want to write this up after Christmas.


Looking forward to see your paper


--
Regards
Maciek



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2012, 02:11
Simon, very good. Just come to think of it, on various drawings it looks as if the exhaustmanifold flange is covered, which would be a must today. The reason is that this flange gets very hot and in case of a HP fueloil pipe burst fueloil might hit the flange causing a dangerous fire. I`m not sure of this point, if you have drawings/photos it is worth while to double check.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2012, 04:43
Thanks Tore for the help. I had to check the alignment of my drawing. For example I just can not add my engine drawing to my U-boat drawing as I have to make sure that pipes align correctly, bolts holes match and under decking pipes align correctly to above deck.

Below in the two drawings you can see I had to align correctly the engine frame bolts hole and the cooling water piping

Fig. 1. U-Boat framing.

(http://img805.imageshack.us/img805/3687/new2ac.jpg)
Fig. 2. U-Boat Engine.

Simon.
Just had a look at you ME lubeoil returnpipe and suggest  you hook up the collecting pipe for the return oil from the reliefvalve of lube oilpump and oilcooler as well as the vibrationdamper to the fwd lubeoil drainpipe from the main engine, see drawing below. The aft drain would have similar connections to the returnpipe from governor servomotor and supercharger.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Nov , 2012, 13:18
Simon
Exhaustmanifold.
Below I have indicated the components your inquired. The seacooling water from the engine ends up into the exhaust manifold coolingcasing, with all the bends and pipes, air could easily be trapped causing problems with the coolingsystem, hence the rather extensive deairation, which ends up in a common funnel aft in the engineroom. On the systemsketch below the principle is shown, howewer as you see the practical solution differ slightly from the systemsketch.
 The other item is the wire for remote reading of the exhaust temperature, for each cylinder, hence 6 wires. The 6 analog rectangular meters is very dominating at the manuevering stand.
Tore

Hi Tore

The 'common funnel aft in the engine room' Can you remember where is this funnel? As I would like to add it to the drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Nov , 2012, 13:54
Hi Tore

I think I have found it (Orange), this would make sence as the water would drain right into the Drainage Piping (Blue) :)

(http://img43.imageshack.us/img43/5396/new1xc.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2012, 14:19
Simon I have been looking to see if I had any picture showing the common funnel, but unfortunately i didn`t find any. Mostly such a funnel or collecting tank is placed on the floorlevel or below. It is not really shaped like a funnel but more like a circular container with a lid where all the pipes disappeared, I think your sketch very well could be it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2012, 23:46
Simon.
Drain/deairation.
If you remember earlier this year we touched upon the same topic in relation to the handpump for the dirty oil and drainage in the same aerea. The idea behind this extensive collecting of spillage is of course to control the bilgewater your pumped overboard to assure you left no trails. You can split the system in two parts the presumable clean water and the oily liquid. The latter very often was drained via a funnel directly in to the dirty oil tank, the other oily mixture like the drains from the ME top, driptrays etc. could end up in a "cannister ". The cooling water drainage could contain oily liquid as the germans used to add an anti corrosive oil in the coolingwater. That`s why we have these numerous tiny pipes which are almost impossible to keep track of.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Nov , 2012, 23:50
Hi Tore

Going back to the air starting system. Orange 'X' is the valve a1. The blue line is the outlet pipe, but what is yellow, this is the inlet? It sence very big for a inlet pipe from the HP bottles?

http://www.uboatarchive.net/U-570Plate15.htm (http://www.uboatarchive.net/U-570Plate15.htm)

(http://img29.imageshack.us/img29/1847/new1vm.jpg)

(http://img705.imageshack.us/img705/5301/new3up.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Nov , 2012, 01:26
Simon.
The " box" on your picture is the main startingvalve housing having 2 pipeconnections: one from the startingair  vessel and then the main supply to the starting air valves on the engine with a branch off to the starting handle from which there is a pipe to the top of the startingair valves on the engine, plus a manometer connection. I have tried to indicate where the pipes leads, but you really cannot see everything.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Nov , 2012, 02:02
Simon.
The " box" on your picture is the main startingvalve housing having 2 pipeconnections: one from the startingair  vessel and then the main supply to the starting air valves on the engine with a branch off to the starting handle from which there is a pipe to the top of the startingair valves on the engine, plus a manometer connection. I have tried to indicate where the pipes leads, but you really cannot see everything.
Tore

Thanks for the information I will update my drawing in the morning. I was able to find the connection for the pressure gauge, it is on the under side of the "Box". Would the gauge be attach somewhere near the pressure hull?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Nov , 2012, 03:09
Simon.
The manometer is situated in the instrument panel above the maneuvering stand, I think it is the manometer in the lower line outboard. The brassign  under would say "drueck anlassleitung" or something like that. I guess you can find a good picture in the engine roomchapter of U boat historia,  I think you should incorporate that panel in your drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Nov , 2012, 05:37
Hi Tore

Going back to the air starting system. Orange 'X' is the valve a1. The blue line is the outlet pipe, but what is yellow, this is the inlet? It sence very big for a inlet pipe from the HP bottles?

http://www.uboatarchive.net/U-570Plate15.htm (http://www.uboatarchive.net/U-570Plate15.htm)

(http://img29.imageshack.us/img29/1847/new1vm.jpg)

(http://img705.imageshack.us/img705/5301/new3up.jpg)
Simon coming back to your remarks on the diameters of the various HP pipelines. First of all don`t forget we are talking about relatively low pressure 30 kg/cm2. The  starting system consists of two pipe types, controlling - and consumption airpipes. If you see the supply air from the airvessel and the supplypipe to the startingvalves in the cylinders, the pipe is relatively large as it requires a lot of 30 kg/cm2 air to run a large diesel. The controlair pipe which is the small branch off to the startinghandle and further on to the top of the startingvalves have practically no consumption, it just put the piston on the top of the cylinder startingvalve a few mm down, thus a small pipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Nov , 2012, 15:15
Tore, thanks again for the information. I have completely redrawn the air supply system. I will post the new drawings in a hour or so, or first thing in the morning.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Nov , 2012, 16:30
(http://imageshack.us/a/img27/5425/70555640.jpg)
Fig. 1. Side view of new Air Starting supply piping.

(http://imageshack.us/a/img38/2172/35242985.jpg)
Fig. 2. Top view of new Air Starting supply piping.

(http://imageshack.us/a/img211/2825/19014294.jpg)
Fig. 3. New Air Starting supply piping under the decking. The layout is correct but the some of the piping and the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Nov , 2012, 00:20
Simon I think this is excellent. The piping which was not on the engine was the various shipyards jobs and module building was not very common in those days. There were deviations from yard to yard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Nov , 2012, 00:31
Simon.
 When looking at your recent engine drawing I discovered a tiny detail on the fuelsupply pipe to the HP pumps which, with you liking of details, might be worth while to incorporate. On U 995 KNM Kaura the pipe between cylinder 7 and 8, is a draincock marked red on the port engine and only a cock connection shown on the stb engine. See the very bad picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Nov , 2012, 12:56
Starting Air Control Supply and Starting Manifold added.

(http://img22.imageshack.us/img22/8792/engineroom2.jpg)
Scale: 1 pixel = 2.35 mm
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Nov , 2012, 23:28
Simon, one step further to perfection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 00:35
(http://imageshack.us/a/img27/5425/70555640.jpg)
Fig. 1. Side view of new Air Starting supply piping.

(http://imageshack.us/a/img38/2172/35242985.jpg)
Fig. 2. Top view of new Air Starting supply piping.

(http://imageshack.us/a/img211/2825/19014294.jpg)
Fig. 3. New Air Starting supply piping under the decking. The layout is correct but the some of the piping and the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 01:21
Starting handles.
I guess you are about to draw the starting handles at the maneuvering stand. They are the same for port and stb engines, so the startinghandles are placed towards port and fuelhandles towards stb on both engines, which means that the linkage seen on the inboard side of the maneuvering stands are different (startinglinkage visible on the stb- and fuellinkage on the port engine). Another detail, all the handles are like double, the second handle is a lockingdevice and has to be pressed in in order to move the levers. .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 18 Nov , 2012, 03:05
Tore, I know, that fuel oil tanks (internal and external) were water-compensated. Were there a problem of mixing fuel oil and water (near the border between the layers of water and fuel)? I mean, if there created some kind of an emulsion?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 04:16
Maciek.
All the fueltanks were seawatercompensated except the settlingtank ( daytanks). There are several reason for that 1. What we call free surface effect has particularly a bad influence on a submarine with neutral buoyancy, and you want to avoid that by allways keeping as many tanks as possible  topped up. 2. As you consume fuel the submarines weight decreases and has to be compensated by increasing the ballast, eg. taking in seawater. The system is that you always have seawater under pressure lead to the bottom of the fueltank and have the fuellines outlet  on the top. The positive pressure under both surface and snorting is maintained by a header tank in the towercasing.
The only fueltanks which are not watercompensated are the two tanks above the engines, one act like a settling tank which means you fill it with fuel  and let the fuel settle and drain possible water while you are running the diesels from the other tank. We never had any emulsion with seawater and dieselfuel as you could have with lubeoil, but the latter did not have any water compensated tanks ( small tanks small surface effect)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 04:27
Maciek.
 As a follow up of my last post it might be a bit easier to look at the drawing below.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 18 Nov , 2012, 04:43
Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm)


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 06:21
Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm (http://uboatarchive.net/U-570GeneralPlan.htm))


--
Thanks, regards
Maciek

Maciek.
The head tank or may better buffertank is not a big tank,just big enough to keep a positive head in the system. It is fed from the coolingwater outlet at the exhaustsilencer, the location is about where I put the arrow on the drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Nov , 2012, 09:42
Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm (http://uboatarchive.net/U-570GeneralPlan.htm))


--
Thanks, regards
Maciek

Maciek.
The head tank or may better buffertank is not a big tank,just big enough to keep a positive head in the system. It is fed from the coolingwater outlet at the exhaustsilencer, the location is about where I put the arrow on the drawing below.
Tore

Tore, can you remember approximately the dimensions of the buffer tank? As this would be a great little detail to add to my main drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Nov , 2012, 10:46
Simon right now I cannot say the volume, you know the idea was not a supply tank and the space available in that area was not great. As you know the tower came in various executions but the design was made for a minimum of towercasing like the 1940 -41 execution. We stripped the wintergarden and reconstructed the towercasing with a minimum of volume keeping all the airducts, vents and buffertanks as originally designed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Nov , 2012, 20:39
(http://imageshack.us/a/img27/5425/70555640.jpg)
Fig. 1. Side view of new Air Starting supply piping.

(http://imageshack.us/a/img38/2172/35242985.jpg)
Fig. 2. Top view of new Air Starting supply piping.

(http://imageshack.us/a/img211/2825/19014294.jpg)
Fig. 3. New Air Starting supply piping under the decking. The layout is correct but the some of the piping and the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Nov , 2012, 01:55
Simon.
I guess the most probable place for  the supply from the 205 kg/cm2 mainline would be starboard above the floorplating. Looking at your photo showing starboard enginefront I have tried to indicate my proposal. Usually the small pipes are the 205 kg/cm2 pipeline and the larger 30 kg/cm2 lines. The indicated 205/30 kg cm2 reducingvalve has a handwheel, that could be a combination of a shut off valve and reducingvalve deviating from the pipeline drawing by making one unit. it is placed relatively easy accessable which makes it probable this is the HP main supply/reducing valve.  The manometers hardly visible outboard starboard could be local manometers showing the supply/reducing pressure because the manometers shown at the drawing you would find up at the instrumentpanel above the maneuvering stand. Se my drawing below and remember it is a guesswork ( hopefully intelligent).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Nov , 2012, 02:00
Simon.
I`m a bit in doubt if the supply line from the compressor would be under the floorplating, I have a liking for outboard on starborad side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Nov , 2012, 06:54
Simon.
Not all ideas are brilliant, I guess I have to revise a few details having given it a second thought.. I found that the HP air systemsketch and the starting air sketch are not in correspondence as they have different type of valves and only the startingair sketch have a direct line to the compressors. I thought the latter solution was a bit strange so I suggest to skip it and stick to the HP systemsketch. Further I have been able to see the details after the HP startingair supply valve and discovered the small airpipe and the filter after the valve so below is my revised proposal.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Nov , 2012, 13:40
Simon.
I guess the most probable place for  the supply from the 205 kg/cm2 mainline would be starboard above the floorplating. Looking at your photo showing starboard enginefront I have tried to indicate my proposal. Usually the small pipes are the 205 kg/cm2 pipeline and the larger 30 kg/cm2 lines. The indicated 205/30 kg cm2 reducingvalve has a handwheel, that could be a combination of a shut off valve and reducingvalve deviating from the pipeline drawing by making one unit. it is placed relatively easy accessable which makes it probable this is the HP main supply/reducing valve.  The manometers hardly visible outboard starboard could be local manometers showing the supply/reducing pressure because the manometers shown at the drawing you would find up at the instrumentpanel above the maneuvering stand. Se my drawing below and remember it is a guesswork ( hopefully intelligent).
Tore

Hi Tore

I been studying all my photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Nov , 2012, 13:55
This is more confusing for me. Below is the port air bottle. I know that the red pipe is the inlet pipe (40 mm) to the Starting Manifold. The blue pipe (15 mm) is the drain line. But the line out of the bottle only looks 15 mm :o :o

(http://img42.imageshack.us/img42/6995/new1pbd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Nov , 2012, 14:06
(http://img803.imageshack.us/img803/7841/graphic1ei.jpg)

Tore, we know the HP bottle ends are the same. Could the German had the drain line at the lower bow end of the bottle (15 mm pipe) and the air outlet at the stem end (40 mm pipe)? This could be why we can not see the 40 mm pipe in the photo above?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Nov , 2012, 19:00
Tore, many updates to the side view.

(http://imageshack.us/a/img42/7527/62005319.jpg)
Fig. 1. New updated drawing.

(http://imageshack.us/a/img211/7314/92316387.jpg)
Fig. 2. old drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Nov , 2012, 22:01
Tore, are the cover plates fixed by screws, bolts or rivets?

(http://img35.imageshack.us/img35/8546/new1fp.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Nov , 2012, 23:15
(http://img803.imageshack.us/img803/7841/graphic1ei.jpg)

Tore, we know the HP bottle ends are the same. Could the German had the drain line at the lower bow end of the bottle (15 mm pipe) and the air outlet at the stem end (40 mm pipe)? This could be why we can not see the 40 mm pipe in the photo above?
Simon.
I was home too late yesterday to look into this, but ready for action this morning. As you have noticed all the airvessels are tilting , this is because you want to collect the water at one end where you put the drain. I have look into the matter of outlet pipe a bit more before I have an answer and shall revert within short.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Nov , 2012, 04:18
Tore, I was always wondering about Fuel oil venting, sounding and test piping :
http://uboatarchive.net/U-570Plate8.htm
http://uboatarchive.net/U-570Plate8A.htm
but I have never been able to figure it out entirely.
For instance, the following piping for inner fuel oil tank Treib
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 04:58
Simon.
I guess we have to reconsider the whole thing. We have located the HP supply regulatingvalve, HP filter and the 205>30 kg/cm2 reductionvalve all placed on starboard side. Between these items are 20mm pipes. Out from the reductionvalve I have not been able to ascertain the pipedimension, but looking at the valvehousing I doubt if it is a 40 mm pipe out from this valve so I assume 20mm. We know that to and from the main startingvalve at the maneuvering stand the pipes are 40mm, thus the pipe from the airvessel should be 40mm.
The pipe at the forward end of the airvessel shown on your photo is definitely a full 20mm airpipe going upwards, hardly a drainpipe, the smaller pipe which can be seen could be a drain. I have not been able to locate any crossover. Unless you have any photos showing otherwise my proposal would be: The supply to the starting airvessels from the reduction valve on starboard side is 20mm, entering both  vessels at lowered forward end, which means that the crossover is a 20 mm pipe. The separate airsupply from the starting air vessel to each engine is from the aft end of the vessel (as you was asking) to the main startingvalve on the engine. It is no 40mm crossconnection.  Each engine takes its startingair from its "own" vessel by the 40mm pipe from the airvessel aft side, the 20mm pipe is only used for topping up (filling) the airvessels. The lay out is based on a direct reversible engine which has a large airconsumption (you have to restart every time you change direction of revolutions) thus the capacity of the airvessel should be for at least 10 starts before topping up.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 05:11
Simon.
Your update is excellent, pipedimensions better and even turning the coolingwater thermometers for  more convenient readings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 05:19
Tore, are the cover plates fixed by screws, bolts or rivets?

(http://img35.imageshack.us/img35/8546/new1fp.jpg)
Simon.
Hard to tell under all that paint,but I believe they were bolts with hexagon heads.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 06:43
Maciek.
Fueltank measuring.
You are particularly interrested in an easy description on sketch 3. On the posted sketch 3 below is red the partition between the green seawater and the lighter fuel on top. Remember the fueltank is always under positive pressure from the buffer/headertank. When you want to measure you equalize the pressure or fuel level in the testpipe by putting the cock in a position so the testpipe  gets an equal liquid level as the tank (red/yellow column in the pipe). When you turn the cock in measured drain position, the red/yellow liquidcolumn is sealed off and is forced by the positive head waterpressure into a inboard measuring canister. You shut off the drain when water is coming, how much water you get in the canister is irrelevant as the only liquid your measure is the fuel and that is accurately fixed. By a table relevant for that particular tank you can read of how much fuel is left in the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Nov , 2012, 07:15
Tore, many thanks!


and is forced by the positive head waterpressure into a inboard measuring canister. You shut off the drain when water is coming, how much water you get in the canister is irrelevant as the only liquid your measure is the fuel and that is accurately fixed


That's the part which I would never guess. Once again, thanks :)


--
Best regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 11:44
Simon.
I guess we have to reconsider the whole thing. We have located the HP supply regulatingvalve, HP filter and the 205>30 kg/cm2 reductionvalve all placed on starboard side. Between these items are 20mm pipes. Out from the reductionvalve I have not been able to ascertain the pipedimension, but looking at the valvehousing I doubt if it is a 40 mm pipe out from this valve so I assume 20mm. We know that to and from the main startingvalve at the maneuvering stand the pipes are 40mm, thus the pipe from the airvessel should be 40mm.
The pipe at the forward end of the airvessel shown on your photo is definitely a full 20mm airpipe going upwards, hardly a drainpipe, the smaller pipe which can be seen could be a drain. I have not been able to locate any crossover. Unless you have any photos showing otherwise my proposal would be: The supply to the starting airvessels from the reduction valve on starboard side is 20mm, entering both  vessels at lowered forward end, which means that the crossover is a 20 mm pipe. The separate airsupply from the starting air vessel to each engine is from the aft end of the vessel (as you was asking) to the main startingvalve on the engine. It is no 40mm crossconnection.  Each engine takes its startingair from its "own" vessel by the 40mm pipe from the airvessel aft side, the 20mm pipe is only used for topping up (filling) the airvessels. The lay out is based on a direct reversible engine which has a large airconsumption (you have to restart every time you change direction of revolutions) thus the capacity of the airvessel should be for at least 10 starts before topping up.
Tore

Tore, this sound great :) :)
 
I have no photo's of the
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 12:09
Simon.
From an engineering point of view it would be unnecessary and more spacedemanding to use a crossover of 40mm as the crossover is only a filling line and not a consumption line. German engineering is optimal so I don`t see why they should choose  a pipesize double of what is needed. You have to find a very good picture/argument to convince me of a 40mm solution. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 13:18
While rechecking the piping this morning I also noted there is a different piping layout between the port and starboard engine, between the air bottles and the starting manifold.  On the port engine the pipe follow the contour of the engine, on the starboard side the same pipe run forward for about 300 mm and then follows the main air vent down.
 
I will update my drawing to show this also.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 13:55
Simon.
Yes, but watch out for the coolingwater returnpipe from the exhaustmanifold to the inlet of the engine attached coolingwater pumps in the same area, it is easy to get mixed up as they are of aproximately the same dimension..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 14:08
Simon.
Yes, but watch out for the coolingwater returnpipe from the exhaustmanifold to the inlet of the engine attached coolingwater pumps in the same area, it is easy to get mixed up as they are of aproximately the same dimension..
Tore

(http://imageshack.us/a/img854/6962/87487006.jpg)
Fig. 1. Port Side

(http://imageshack.us/a/img13/4438/71648662.jpg)
Fig. 2. Starboard.
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 14:31
Simon.
Interesting photos. On stb side I guess you have noticed that on the reducing valve the outgoing pipe (30 kg/cm2) is  a bit  larger diameter than the ingoing (205 Kg/cm2). On the port side it is an interesting detail on the airinduction system which we can use when you shall go into details with regard to the supercharger system. Very good! ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 14:39
Red  = 40 mm
Blue - 30 mm
Green = 10 mm
(http://img580.imageshack.us/img580/34/new4t.jpg)

(http://img195.imageshack.us/img195/4070/new5k.jpg)
I found the cross over  ;D ;D You can just see it at the bottom of the photo.
(source: U-995 DVD http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Nov , 2012, 14:41
Simon.
Well done!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 14:44
Simon.
Yes, but watch out for the coolingwater returnpipe from the exhaustmanifold to the inlet of the engine attached coolingwater pumps in the same area, it is easy to get mixed up as they are of aproximately the same dimension..
Tore

(http://imageshack.us/a/img854/6962/87487006.jpg)
Fig. 1. Port Side

(http://imageshack.us/a/img13/4438/71648662.jpg)
Fig. 2. Starboard.
(source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml))


Here a better view of the port pipe, you can easily see how the pipe contour the engine and gone between the engine and the exhaust.
(http://img546.imageshack.us/img546/4932/portimg6480.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 14:52
Tore, what time zone are you in, is it GTM +1:00?

If so, being so far north, it must be getting dark very early currectly about 5:00pm??
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Nov , 2012, 17:21
Tore, found a small error in the placement of the Air Starting Rocker Arm. It needed to move the end of the Rocker Arm, closer toward the fuel pump.

(http://img580.imageshack.us/img580/9444/new1ro.jpg)
Fig. 1. New drawing.

(http://img571.imageshack.us/img571/2032/new4rb.jpg)
Fig. 2. Old drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 00:54
Simon.
New enginetop drawing.
Seems to be fine as usual, however I just noticed you give the exhaustvalve ample lubrication via two lines whereas the inletvalve has none. As far as I can see both valves have lubrication but at different inlet points, exhaust from the side and inlet from the top, see picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 01:02
Simon.
We are in the central Europe zone, GMT +1 hour. Right now it gets dark at 1600 and daybreak at 0900 in my area, but further north about half of the country don`t get sun at all starting at the North Cape in a few days.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 01:09
Simon .
Your new pictures showing the forward front and outboard side of the engine are great and useful for coming scrutinizing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Nov , 2012, 05:54
Hi Gents


I was able to find following information: the diameter of HP air piping leading to starting air flasks: internal - 36,5 mm, external - 44,5 mm.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 05:55
Simon. On a few photos from the U 995 engineroom, outboard gratings are fitted between the engines and hullside. I cannot remember we ever had them and I don`t see the purpose for it . I guess they are installed to prevent visitors from crawling into that cramped space and suggest you skip it on your drawings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 11:52
Hi Maciek!
I guess the dimension fit pretty much in with the pipes in Simon's drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Nov , 2012, 12:06
Hi Gents


I was able to find following information: the diameter of HP air piping leading to starting air flasks: internal - 36,5 mm, external - 44,5 mm.


--
Regards
Maciek


Hi Maciek!
I guess the dimension fit pretty much in with the pipes in Simon's drawing.
Tore

Yes, it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Nov , 2012, 13:54
Tore, the line between the air compressor and the cross-over, what diameter do you think it is?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 14:29
Simon.
I am not sure  it is a line if you cannot see it on a photo. If you are able to confirm it visually then  I would guess the same as the 30 kg/cm2 pipe after the reducingvalve see picture below, it seems to be at least 20 mm. But this is one of the reasons I believe I`m in doubt of this pipe why should it be a direct 205 kg/cm2 connection directly without a reducingvalve to a 30 kg/cm2 system? That is quite a hazard, more over this pipe is not shown on the HP air diagram. The only reason I can think of is that it could be an emergency connection the other way eg. the startingair vessel used to supply air to the HPsystem in that case it would have been easier and safer to do it via the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2012, 14:47
Simon. I just checked the starting air system for the MAN engine. The direct line from the compressor shown on the diagram for the GW engine is not drawn in I guess my assumption is correct it is not such a connection. It would be completely  crazy. See the MAN system below, remember the MAN has a two stage reduction.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 01:40
Simon.
I have checked the various HP air system sketches  in my possession and except for the simple GW starting airsketch non of the others shows any direct connection between the compressors and the starting air crossoverline. As you see on the sketch below it is a 2nd connection from the compressors which is connected, (as I presumed) directly to the HP manifold in the controlroom and no connection to the crossover or the air starting system as the main HP line via a reducingvalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Nov , 2012, 01:40
Hi


Just a thought, maybe the "starting air diagram for GW" (with additional, direct connection to the compressor) is the version for early boats (U93-U97) made by Krupp Yard, equipped with two electric compressors (similar issue as  Cooling-water system diagrams). The later boats (with GW and MAN engines) had one Junkers compressor (Luft Verdichter 1) and one electric driven compressor (Luft Verdichter 2). And in these boats, the direct connection was removed?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 02:02
Maciek-
An interesting idea, in that case the line would have to have a reducingvalve 205kg/cm2>30kg/cm2. Theoretically you could take a bleed off from the 2nd stage on the E-compressor ( appr. 30 kg/cm2), however on a freepiston compressor (Junker) I guess it would upset the balance which makes it impossible. If the 2nd connection to the control room is from the original design, including U92-97, which I believe, then I still fail to see why you should have a 3rd connection and not just a bleed off from the 2nd. pipe directly or rather via a reducingvalve in the engineroom to the crossover.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Nov , 2012, 02:33
Or - other idea (inspired by Design Study of Former German Submarine  - Type IXC: "The starting air system supplies air for starting the main engines and the diesel air compressor. " http://uboatarchive.net/DesignStudiesTypeIXC.htm ) : this line exists only on boats with Junkers compressors (all type VIIC except U92-U97), because compressed air was used to start Junkers compressor (though I have always thought, that Ju-Verdichter was started manually).
Gents, in above mentioned report try use search for string "starting air" - maybe it tells something more...


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Nov , 2012, 02:38
compressed air was used to start Junkers compressor (though I have always thought, that Ju-Verdichter was started manually).


Quote
For starting up, compressed air is directed on the pistons brought into the outside position.
page 49, http://uboatarchive.net/U-570BritishReport.htm


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 05:10
Maciek.
Brilliant! That`s it, we were fooled by  a sketch connection directly to the compressor assuming it was a supplyline from the compressor, forgetting the startingair to the Junker compressor which of course I shouldn't  have forgotten. Why was it different on the MAN system?  If you look at the system for the MAN engines, the crossover on the  system has a pressure of 75 kg/cm2 as the 2nd stage reduction of 75>30 kg/cm2 is on each separate engine thus you cannot use the crossover for starting air supply on the MAN system.On the MAN system the startingair for the Junker is taken from the ordinary HP supplyline of 205 kg/cm2 in the aft torpedoroom where it is connected to the Junker starting valve via an ordinary reductionvalve 205>30 kg/cm2.
 Simon, to make it simple: on the GW installations like U1308 and U 995 it is indeed a connection, presumably at least 20mm, from the crossover to the  startingvalve of the opposed piston Junker dieselcompressor which was installed on all VIICs after U 97. It is not a supply from the compressors. Thanks to Maciek.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 07:03
Simon-
Junker compressor startingsystem.
Further to my earlier post, the starting airpipe connection from the crossover to the Junker is via a compressor starting airvessel underneath the Junker. From this vessel the pipe goes to the starting valve at the center of the compressor as indicated on the bad photo below. I guess the size of the pipe from the crossover should not exceed 20 mm, rather smaller, as it is only a topping up line. The consumption for starting the compressor is taken from the starting airvessel. May be you are able to guess the dimension of the pipe by looking at the photo or better you shall find a good quality picture a U historia or may be from one of your exellent resources..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Nov , 2012, 11:49
Air Starting System

(http://imageshack.us/a/img685/559/10609362.jpg)
Fig. 1. Port Side.

(http://imageshack.us/a/img692/5677/78270862.jpg)
Fig. 2. Starboard Side.

(http://imageshack.us/a/img818/2058/99123653.jpg)
Fig. 3. Port and starboard Engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 13:32
Simon.
 It`s always a pleasure to see your drawings. As usual I have a few minor remarks. At the end of the fuelrack both stb. and port forward are endsprings enclosed in a steelsleeve, see picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 14:03
Simon.
Exhaust and inlet valve lubrication.
 I think it is a confusion here. In the British report from the inspection of the U 570 is mentioned that the cylinders are lubricated by luboilpipes inboard and outboard from the Gruetzner lubricators, further is mentioned that the inlet-and the exhaustvalves are lubricated by a camshaftdriven "mechanical pump".
Separate luboil connection to the cylinder liners is a very oldfashioned way of lubricating cylinderliners, in Germany during the years 1930-40 they were usually lubricated by the oil in the crankcase which is distributed and controlled in the cylinder by the pistonring arrangement. I cannot remember we had such a separate lubrication. I have not been able to locate any luboilpipes to the cylinderliners nor a "mechanical camshaftdriven luboilpump" which should take care of the valvelubrication except the Gruetzner lubricators having 12 pipeoutlets on each engine. In a way it is driven off the camshaft by a rod from the exhaust rockerarm on cyl 1. So if not somebody can explain and confirm the report of U 570 I`m inclined to skip the cylinder lubrication and let the Gruetzner take care of the valvestem lubrication.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 14:14
Simon.
Airstarting system.
This just the way it is, well done I guess it is an extra  small pipe from the forward end of the starting airvessel probably going  up to the pressuregauge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2012, 14:45
To all friends in US happy Thanksgiving!  to Simon good morning and  friends in Europe good night, I think it was an interesting day and I`m hitting the sack.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 22 Nov , 2012, 16:45
Thanks Tore from the U.S. ! I am thankful that you are able to give us so much new information and help us with our studies!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Nov , 2012, 20:39
Gruetzner lubricator

(http://imageshack.us/a/img571/5714/new2u.jpg)

(http://imageshack.us/a/img690/4688/new1yg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Nov , 2012, 22:00
Hi Tore/Maciek

On Plate 10:  Fuel oil compensating system (circulating water under pressure), the handle for valve 'B' are located within the engine room?

http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)

(http://img692.imageshack.us/img692/2858/new1z.jpg)

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2012, 00:02
Simon.
Your drawings are getting more and more details. Knowing your likings for details, have a look at my bad picture below. The knife filters have usually a wheel or a handle at the top which is connected to a "brush" inside the filter cleaning the filterelement by turning the handle. I believe on the picture below it is a T-handle. I don`t fully understand the two smaller pipes coming from the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2012, 05:33
Simon.
Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the hight difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2012, 06:51
Simon-
Side view engine drawing.
I just had another look on the fuelsupply/drainpipes realizing it is not yet finished but nevertheless I put forward a few remarks. It looks to me that the drain from the knife filter driptray is hooked up to the suctionside of the engine driven fuel supplypump instead of a funnel/collectingtank and what I presume is the supplyline to the knife filter seems to go up and not horizontally to the filter. See my picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Nov , 2012, 12:00
Hi Tore

I am trying to update my fuel lines now (the copper colour piping).
(http://imageshack.us/a/img571/5714/new2u.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2012, 13:10
Simon.
It is a bit difficult to explain without the supply pipe from the daytank and the next cock so I introduce them as well. Fuel comes from the overhead daytank to cock 1 violet pipe. normally it goes to the fuel supplypump suction pressure boosted an goes from the pump (red) to a cock directing the fuel to the dual filter comes from the filter to the next cock from there to the knifefilter and the HP fuelpumps (still red). The cocks makes it possible to shut off either pump or the dualfilter or both. then you can operate for emergency the engine by the gravity supply of the overheadtank and filter the fuel by the knife filter. The yellow drain from the knifefilter is not connected to the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2012, 13:27
Simon the above picture was lousy I am trying a better quality below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2012, 00:40
Simon .
Just another try to see if I can produce a better quality picture of the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 02:22
Thanks Tore

Don't do any drawing today, so will have a look tomorrow.

Off to bed now  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 14:07
The yellow drain from the knifefilter is not connected to the system.

Hi Tore

The drain line is this drawing may look like its connected to this system, but I have the fuel system on a different layer. I will add this layer to the drawing and post pictures for you.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 14:33
New fuel oil filter and now including inlet piping

(http://img593.imageshack.us/img593/6791/new1im.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2012, 14:40
Very good Simon, it is quite a visible part of the engine so I guess it is nice to have it correct. I have not been able to establish the in and out pipeconnections on the knife filter. Some of them have connection in the bottom, others on the top. I would guess bottom towards the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 14:46
Very good Simon, it is quite a visible part of the engine so I guess it is nice to have it correct. I have not been able to establish the in and out pipeconnections on the knife filter. Some of them have connection in the bottom, others on the top. I would guess bottom towards the engine.
Tore

I was just about to ask you this question and was writing it up but you must be faster than me ;D ;D I will feed them into the back of the filter.

I will post new drawings is a few day, as I am away tomorrow.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 14:52
Tore, here the fuel oil layer added, should keep you busy tomorrow ;)

(http://img26.imageshack.us/img26/2738/new4vs.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Nov , 2012, 14:56
Tore/or anyone, not sure if you know this, but the forum will resize my drawings to 800 px, if you left-hand click the drawings it will rescale the drawing to it original size.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2012, 15:00
Very good Simon I`m off to bed now, may be you put the T handle on the filter by tommorrow morning. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2012, 02:10
Simon.
You are right the fuel layer shall keep me busy today. I`ll start at the top. The tank you have drawn up under the pressurehull is the hearth or rather the stomach of the whole system. The tank is split in two halves along a mid shipline and function like a purifyer, clarifyer and a head/supplytank to the engines. It is fed by white pipeline  on the picture below from the fuel pressure watercompensated bunkertank system to the aft end of the headtank via cocks.
 During normal service you take fuel for both engines from one of the tanks, while the other is filled from the bunkertanks and then let the fuel settle so the water and impurities collects in the bottom of the tank, that takes a while but  it is ready for use when the other tank is nearly empty. Below is a drawing where I have tried to show the details of the supplysystem. Amongst the mess of arrows I have indicated a valve and line in yellow, leading fuel to the Junker compressor which we shouldn't`t forget this time. The system sketch is showing as usual the MAN system with fuel supplypump driven off from the camshaft aft end, as mentioned before remember on the GW it is driven from the crankshafts  forward end.
 With so many arrows  I think I better split this up and go into details of the supply system from the daytank in a separate post.
 A small detail to mention, the tank is fitted with 3 brackets on each side to the upper frames of the pressurehull, the aft fitting is  fixed by wire to welded on eyes to the plating as the tank end does not quite meet the aft frame. The light underneath the tank seems to be on the small side , the diameter is about a 5th or 6th of the length of the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2012, 04:53
Simon
The fuelsupply system from the daytank.
The fuel from the overhead daytank goes from the selected tank via a cock which, when open for delivery (red) allows the other tank to open for supply (green). The red supply lines to both engines goes along the engines  as a black pipe ( it was never black in my time) to the selection cock on the forward engine side, the system from here has been explained previously. On the forward side of the daytank are sight glasses for each tank as well as drainpipes with cocks and ventpipes all ending up in a collecting tank. These pipes are all fitted on the port engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 Nov , 2012, 05:26
Hi Simon
On Plate 10:  Fuel oil compensating system (circulating water under pressure), the handle for valve 'B' are located within the engine room?


In my opinion, there was no need to make this valves operational from inside of the pressure hull.
Moreover, in the section Openings in the pressure hull of http://uboatarchive.net/Manual.htm, there
is no mention about shafts for these valves (either in diesel engine room as well as in Control room).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2012, 05:39
Hi Simon
On Plate 10:  Fuel oil compensating system (circulating water under pressure), the handle for valve 'B' are located within the engine room?


In my opinion, there was no need to make this valves operational from inside of the pressure hull.
Moreover, in the section Openings in the pressure hull of http://uboatarchive.net/Manual.htm, there
is no mention about shafts for these valves (either in diesel engine room as well as in Control room).


--
Regards
Maciek
Yes I agree Maciek, see my answer nov. 23rd.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2012, 05:55
Simon
Fuel supply system from day tank.
Checking my post earlier today on this subject I realize the relevant picture was not posted, I guess it is becoming too many pictures. Anyhow below is the picture which I hope gives a better understanding of the text.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2012, 09:31
Simon.
Fuel drain.
The main fuel drain on the engine goes along the engine just about where the cylindercovers meets the cylinder block, it collect the spill from each cylindercover via funnels and leads to the forward of the engines joins the drain (yellow) from the knifefilter before it drain into the fuel draintank. It is no T piece where the fuel filter enters the maindrain, just a welded branch with threads for the connection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2012, 01:45
Simon.
Crankcase doors.
Now we are really going into details, but I happened to notice some small discrepancies on your bedplate/ crankcasedoors. As you see on the picture below, the stiffening knees between the crankcasedoors are ending a bit higher up between the doors and the narrow end cover up forward is protruding further down than the ordinary crankcase doors. The narrow frontcover is just a plate. Crayzy details hardly noticed by anybody but mee.  ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2012, 06:50
Simon .
Drain box.
Realizing your latest drawing  may not yet be completed I shall nevertheless mention this small detail.   The drainbox up forward I believe it is a bit larger almost the full height of the camshaftcover, see picture below.You said it before, you love details. ;D 
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2012, 08:02
Simon.
Crankcase doors and floorplating.
You have probably not yet fitted the floorplating in the engine room, prior to that, be aware of a detail. It is a fairly big step down to the floorplating between the engines, the reason for that is you want to have access to the crankcase through the crankcasedoors without having to dismantle the floor. By lowering the floorplates you are making it difficult to have access to the engine top which require frequent inspections and maintenance. A stepplate is hinged all along the engine  right below the camshaft covers. On the U 995 it is folded down, howewer when needed you fold it up and behind the plates are folded in brackets which you fold out to get support for the plates. See picture below. You can get further detail on the U historia.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Nov , 2012, 23:56
Hi Tore

Just letting you know that were will be no new drawings for the next few days. I am taking a break from drawing and catch-up on some other work.

Simon.
Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the hight difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore

Tore, that dimension do you think this pipe would be? I was thinking about 75 mm.


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2012, 01:30
Hi Tore

Just letting you know that were will be no new drawings for the next few days. I am taking a break from drawing and catch-up on some other work.

Simon.

Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the height difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore

Tore, that dimension do you think this pipe would be? I was thinking about 75 mm.



Simon.
To me 75 mm diameter seems to be on the large side. I don`t think it would be any bigger than the fuelpipe from the tanks entering the engineroom as seen on the picture below previously displaid.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2012, 01:48
Simon
It sounds strange but I guess there are other things going on in the world but VIICs. Looking forward to seeing your upgraded drawings in due time! :D


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 28 Nov , 2012, 03:19
Hi Tore, Simon


Take a look into quite old thread here:
http://models.rokket.biz/index.php?topic=106.msg9557#msg9557


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2012, 08:55
Hi Tore, Simon


Take a look into quite old thread here:
http://models.rokket.biz/index.php?topic=106.msg9557#msg9557 (http://models.rokket.biz/index.php?topic=106.msg9557#msg9557)
 Hi Maciek.
Interesting thread. I agree to your identification of the Kingstons. However the biggest pipe/duct is to my opinion too large for being a soundingpipe, in fact too large for any liquid. My suggestion would be it is possibly the main ventpipe joining the stb ballasttank 2 to the commom  main ventvalve operated from the control room, it is only in use when ballast/fueltanks 2 port and stb are  used as ballast tanks. The pipe is indeed pointing downwards, but the appearant heavy corrosion  could have removed the support, anyhow I  don`t have any other suggestion right now.
 As the seawater compensating pipe is only supplying the same volume of liquid as the fuelpipe take out of the tank, I don`t see any reason  that the compensating pipe should have to be of an other dimension than the fuelpipe shown on my picture above.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 Nov , 2012, 01:37
Hi Tore
However the biggest pipe/duct is to my opinion too large for being a soundingpipe, in fact too large for any liquid. My suggestion would be it is possibly the main ventpipe joining the stb ballasttank 2 to the commom  main ventvalve operated from the control room, it is only in use when ballast/fueltanks 2 port and stb are  used as ballast tanks. The pipe is indeed pointing downwards, but the appearant heavy corrosion  could have removed the support, anyhow I  don`t have any other suggestion right now.

Isn't this pipe too thin for vent duct? On this plate:
http://uboatarchive.net/U-570Plate28.htm
is given cross-section area: 3,167 m2. Based on this, I would estimate the diameter for about 1 m.
Also, here is Simon's drawing showing this arrangement:
http://models.rokket.biz/index.php?topic=106.msg10098#msg10098
Comparing to the wreck's photo, it seems that vent ducts are a little bit larger.


As the seawater compensating pipe is only supplying the same volume of liquid as the fuelpipe take out of the tank, I don`t see any reason  that the compensating pipe should have to be of an other dimension than the fuelpipe shown on my picture above.


Well, that's the point.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Nov , 2012, 06:16
Hi Maciek.
The VIICs are well known to have a quick divingtime and have a remarkable Kingston flood openings, but having openings in excess of 3 square meters in a pipe under the casing, I would believe, is too much. It would require a ventdiameter of nearly 2 meters almost the size of the conningtower across. I guess the crosssection area described in  the diagram refer to the 4 Kingston valves eg. floodarea of seawater into the bottom of the saddletank . That would be approximately  4x 0,8 square meters which, looking at the 4 square Kingston openings, seems to be correct. Down below I have posted  sketches showing the various components relation to the diameter of the pressurehull 4,7 meter. The distance between the frames is app. 0,5 m .
In the area of this ventpipe  the max. height between the casing deck and pressurehull is, I guess, 0,70 m. If you compare the vent pipepipe drawing for fwd. ballastanks port and stb. plate 28 with the drawn frame hight app 15 cm, you would end up with a pipediameter of approximately 250 max 300mm, easily fitted under the casing deck and probably not too far away from the biggest pipe shown on the wreck. The  bend on the end of the pipe could be where the pipe would have entered the saddletank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Nov , 2012, 06:55
Hi Maciek.
Further to my latest post I`m showing below a detail of my ventpipe theory. The emergency shut off for each individual ballasttank is showing the pipedimension, as you see the pipe is of a moderate size.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Dec , 2012, 01:17
Hi Tore

Dani, over at U-Historia as updated his 'Fuel' page.

http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&sl=es&tl=en&u=http%3A%2F%2Fwww.u-historia.com%2Fuhistoria%2Ftecnico%2Fvisitaguiada%2Fvisita.htm (http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&sl=es&tl=en&u=http%3A%2F%2Fwww.u-historia.com%2Fuhistoria%2Ftecnico%2Fvisitaguiada%2Fvisita.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2012, 02:03
Simon this is exellent, I`ll have a closer look at it later today.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2012, 06:20
Simon.
Fuelsystem
The thread shows some interesting new drawings and photos. The English translation is not easy to understand as some strange words  and sentences are used. I guess the translator do not fully understand the system which is a must for a correct technical English text. I stick to my short and incomplete description of Nov. 25Th. and if somebody would have a question based on the new pictures and drawings I shall be happy to answere if I can.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Dec , 2012, 02:12
Hi Tore,


thanks for drawings illustrating scale problem. Location of cross-section area (near vents drawing) confused me totally and I forgot about estimating sizes and diameters.


I have got some kind of operational question: as far as I know, the primary station for helmsman was located in conning tower, and the second one was in control room (I think there was also possibility to move control panel from conning tower to the bridge, when performing docking maneuvers (or so on).  When RNoN operated KMN Kaura, which station was used typically (conning tower or control room)? Did it depend on cruise condition (submerged/surfaced)? Also, if helmsman was in conning tower, was there enough space for operating (riding around) fixed-eye-level periscope?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Dec , 2012, 04:51
Hi Maciek.
Submerged we usually had the helmsman placed in the controlroom , together with the hydroplaneoperators. The reason for that is the officer on watch was  responsible for both functions and you want to be in physical contact with all three. During surface patrol in peacetime and fair weather it could happen the helmsman was on the bridge as well as during manoeuvring during docking, otherwise in the controlroom. Diving station the helmsman was in the controlroom.  During attack some CO wanted to have the helmsman in the conningtower but as far as I remember he was mostly in the controlroom.
Surfaced in rough weather ( when the bridge was washed over) we  operated the sub from the controlroom using the navigation periscope and shut the top hatch.
You might find a difference between the German way of operation as they used the engineering officer as diving/trimming officer whereas we and the RN used a navigator, No1, for this function. Our engineering officer was used during attack for calculating distances and stationed in the controlroom, No1 was in charge of the helmsman and hydroplanes/trimming and stationed in the controlroom as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Dec , 2012, 05:41
Maciek.
Helmsman space in conningtower.
I see I forgot to comment on the helmsmans space in the conningtower. I don`t think it was very spacey,but it didn`t obstruct the turning of the attack periscope. If you look at the sketch below you see the distance between the periscope and conningtower pressureside turned 180 degrees leaving "plenty" of space for the helmsman. Note the the conningtower hatch is placed off center midship. The helmsman in heavy winter clothings shows the space.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Dec , 2012, 08:21
Tore, thanks for your comments on helmsman stations and control room parties duties.
Well, indeed, from drawings it seems, that there is enough space in conning tower for
helmsman and periscope operator. I'm not sure, but wasn't there a third person - TDC operator?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Dec , 2012, 09:53
Hi Maciek
I guess it could be 3 persons in the conningtower, but then it would be cramped. We usually  only had the CO and sometimes a TDC operator in the tower during attack. As I said the helmsman was usually in the controlroom as NO1 was in charge of both the trimming, hydroplanes and navigation (helmsman).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Dec , 2012, 19:23
In the area of this ventpipe  the max. height between the casing deck and pressurehull is, I guess, 0,70 m. If you compare the vent pipepipe drawing for fwd. ballastanks port and stb. plate 28 with the drawn frame hight app 15 cm, you would end up with a pipediameter of approximately 250 max 300mm, easily fitted under the casing deck and probably not too far away from the biggest pipe shown on the wreck.

I just checked my drawing, I went for 275 mm  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Dec , 2012, 20:45
Hi Tore

Just letting you know that were will be no new drawings for the next few days. I am taking a break from drawing and catch-up on some other work.

Simon.

Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the height difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore

Tore, that dimension do you think this pipe would be? I was thinking about 75 mm.



Simon.
To me 75 mm diameter seems to be on the large side. I don`t think it would be any bigger than the fuelpipe from the tanks entering the engineroom as seen on the picture below previously displaid.
Tore

I just checked dive video of U-352 and U-1021, and I found no evidence of this pipe. I think after 60 years at the bottom of the sea all evidence is gone :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 00:03
Simon.
Ventpipediameter.
I guess your choice of diameter is pretty much correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 00:19
Simon
Seawater compensating pipes.
Hi Tore

Just letting you know that were will be no new drawings for the next few days. I am taking a break from drawing and catch-up on some other work.

Simon.

Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the height difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore

Tore, that dimension do you think this pipe would be? I was thinking about 75 mm.



Simon.
To me 75 mm diameter seems to be on the large side. I don`t think it would be any bigger than the fuelpipe from the tanks entering the engineroom as seen on the picture below previously displaid.
Tore

I just checked dive video of U-352 and U-1021, and I found no evidence of this pipe. I think after 60 years at the bottom of the sea all evidence is gone :(
Simon.
60 years at the bottom of the sea takes its toll I can assure you, it`s 59 years since I came on board the U 995 and quite a bit has changed both to me and the U 995 even at the surface. ;D
I have studied the diameter of the pipe once more and reconsidered my guesswork.  I believe your estimate of 75mm is not too far away, may be a fraction smaller but I should think you could go for it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Dec , 2012, 01:18
Hi Gents


Few days ago, on 1st December, it has been 60 years ago, when U995 entered into the service as KNM Kaura.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 01:43
Maciek
You are absolutely right, unbelievable it is 60 years since she was commissioned as KNM Kaura, but the date was December 6Th 1952. I embarked May 1953. She was our first and only VIIC/41 the two others were VIIC U 926 KNM Kya and VIIC U 1202 KNM Kinn.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Dec , 2012, 10:28
Fuel oil compensating system

Tore,
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Dec , 2012, 11:09
Simon
Seawater compensating pipes.
Hi Tore

Just letting you know that were will be no new drawings for the next few days. I am taking a break from drawing and catch-up on some other work.

Simon.

Fueloil compensating valves fuel oil saddle tanks.
The upper drawing you are showing is the system outside the pressurehull and I don`t believe the valves are operated from inside the pressurehull. The fuel/ballast saddletank 2 and 4 starboard and port are just made of light steel sheets and do not withstand any large pressure. They are equipped both as full fueloil bunkertanks and  full ballast tanks with all the connections required. The encircled valves have two positions either in direct connection with the head/buffertank in the tower or in contact with the sea via a small compensatingbox in the bottom of the tank. As fueltank the first position shall be used to ensure the compensating head is allways positive but not exceeding the differential pressure (the height difference between the headtank in the tower and the fueltank). Eg. irrelevant of the ambient pressure regardless the diving depth. 
Tore

Tore, that dimension do you think this pipe would be? I was thinking about 75 mm.



Simon.
To me 75 mm diameter seems to be on the large side. I don`t think it would be any bigger than the fuelpipe from the tanks entering the engineroom as seen on the picture below previously displaid.
Tore

I just checked dive video of U-352 and U-1021, and I found no evidence of this pipe. I think after 60 years at the bottom of the sea all evidence is gone :(
Simon.
60 years at the bottom of the sea takes its toll I can assure you, it`s 59 years since I came on board the U 995 and quite a bit has changed both to me and the U 995 even at the surface. ;D
I have studied the diameter of the pipe once more and reconsidered my guesswork.  I believe your estimate of 75mm is not too far away, may be a fraction smaller but I should think you could go for it.
Tore

I have decided to go for 60 mm.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 11:50
Simon
I guess that`s not far from the correct dimension.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 13:11
Simon
Fuel compensating saddle ballasttanks
The valve b is a valve only in use when you select the mode you want to use the saddletanks,as fuel tanks or ballasttanks. It is a double seated valve with only two positions  either in direct contact with the head tank in the conningtower when the saddletank is used as fueltank or in direct contact with the sea when the saddletank is used as ballasttank. I believe it is controlled from outside the pressurehull under the casingdeck as it is not often used. I think it is a hatch in the deck for access.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Dec , 2012, 14:07
Simon
Fuel compensating saddle ballasttanks
The valve b is a valve only in use when you select the mode you want to use the saddletanks,as fuel tanks or ballasttanks. It is a double seated valve with only two positions  either in direct contact with the head tank in the conningtower when the saddletank is used as fueltank or in direct contact with the sea when the saddletank is used as ballasttank. I believe it is controlled from outside the pressurehull under the casingdeck as it is not often used. I think it is a hatch in the deck for access.
Tore

Thanks Tore.

I have checked all my photo's and checked dive videos and found no evidence of these pipes. So this morning I started checking deck hatches and I think I can location the positions they enter the saddle tanks using the hatches. I will use this as my glide for the drawing.

Do you think the open end to the sea would have a pipe screen over the end to stop sea weeds etc entering the system?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2012, 14:25
Simon
Sea connection for compensatingpipe.
I don`t believe there is much of a screen. This connection is not for transport of any seawater (throughflow) it is merely a seapressure equalizer connection. The Kingstons take care of the filling of the tank. I`ll see if I can figure out something better tommorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Dec , 2012, 14:44
Simon
Sea connection for compensatingpipe.
I don`t believe there is much of a screen. This connection is not for transport of any seawater (throughflow) it is merely a seapressure equalizer connection. The Kingstons take care of the filling of the tank. I`ll see if I can figure out something better tommorrow.
Tore

Thanks, Tore.

I imagine if the opening is only for equalizing this open could be a lot small than the 60 mm pipe.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2012, 08:31
Simon.
Saddle fuel/ballasttanks
I have not been able to find any drawing or picture of this arrangement. I have looked for a seawater connection but there is non. My conclusion would be, when used as ballasttanks the Kingstons are open and the tank is in direct contact with the sea. Thus when the compensatingpipe is shut to the compensatingtank
( headtank) the pipe is in contact with the seawater via the Kingstons.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Dec , 2012, 14:04
Simon
Fuel compensating saddle ballasttanks
The valve b is a valve only in use when you select the mode you want to use the saddletanks,as fuel tanks or ballasttanks. It is a double seated valve with only two positions  either in direct contact with the head tank in the conningtower when the saddletank is used as fueltank or in direct contact with the sea when the saddletank is used as ballasttank. I believe it is controlled from outside the pressurehull under the casingdeck as it is not often used. I think it is a hatch in the deck for access.
Tore

Thanks Tore.

I have checked all my photo's and checked dive videos and found no evidence of these pipes. So this morning I started checking deck hatches and I think I can location the positions they enter the saddle tanks using the hatches. I will use this as my glide for the drawing.

Do you think the open end to the sea would have a pipe screen over the end to stop sea weeds etc entering the system?

I think I may have an explanation why I can not found any evidence of these pipes. I previous imagine those pipes would run just above the pressure hull, but now I believe there is not enough room, so the Germans run those pipes just under the wooden deck. As both the decking of U-352 and U-1021 are gone, this is why I can not found these pipes in the dive videos.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2012, 14:22
Simon.
That may be.  I think I have seen a drawing of the compensating box in the bottom of the saddletank. See below,  I made a rough pencil sketch indicating where to look for it you have more materials to look into than me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2012, 14:34
Simon.
Further to my last post I may add that I believe the compensating pipe goes into the box and a pipe goes out of the box and act like a syphon for the compensatingwater from the box  to the bottom of the saddletank when in fuelmode.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Dec , 2012, 23:50
Hi Tore

A big redrawing of the piping under the decking!

There is little detail we know about this piping outside the pressure hull. The only thing we know for sure is the pressure hull opening (Figure 4).  I initially imagine the piping run just above pressure hull but I now know there is just not enough room to do this.

Next I needed to workout where the pipes enter the saddle tanks. I did this by matching deck hatches. I ended up using the four hatch covers for the exhaust gas and emergency blowing systems.

I also initially imagine the piping for the exhaust gas and emergency blowing systems run just above pressure hull but now I know there is just no room. So I move most of the exhaust gas and emergency blowing piping and Fuel oil compensating piping to just under the wooden deck. This was confirmed in a photo in the book The U-boat By Eberhard Rossler, where you can see one of the exhaust gas and emergency blowing systems pipe just below the deck.

(http://imageshack.us/a/img442/4509/new4c.jpg)
Fig. 1. Openings.

(http://imageshack.us/a/img341/8302/new5a.jpg)
Fig. 2. Piping.

(http://imageshack.us/a/img805/2271/new6ad.jpg)
Fig. 3. Hatch covers.

(http://imageshack.us/a/img189/9186/new8k.jpg)
Fig. 4. Pressure Hull opening.

(http://imageshack.us/a/img827/5474/new1dw.jpg)
Fig. 5. Close-up.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 01:34
Simon.
Indeed substantial drawing work. A detail with regard to the saddletanks. I guess fwd and aft of the conningtower area the saddletanks have a sharp bend towards the pressurehull which facilitates the pipeconnections to the tanks, see drawing below. I don`t have a good picture of the casing deck in this area but I guess the deckhatches would give an indication of the location for the various deckoperated valves.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 06:29
Simon.
Mainvents fuel/ ballasttanks 2&4.
I had a closer look at the mainvents inlet to the fuel/ ballast saddle tanks 2 port and stb. compairing in it with a GA drawing of 1943 and adjusting it to approximately to your scaledrawing. When using the aft  battery hatch as you use as the fixed point, it looks to me that your drawing has the mainvent inletpipe about 650-750 mm further forward than on the GA drawing.
See drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Dec , 2012, 07:59
Tore, one off-topic question related to the high pressure compressed air system. In general, compressed air flasks are connected using "star topology" - with high pressure air distributor as central/control hub. With this air distributor are also connected air compressors (even with two lines - one primary and one backup/secondary).


When there was a need to recharge air flask, after starting compressors, were all air banks filled at the same time or were they filled one after another?
And, when rebuilding air supply, were both compressors running?


http://uboatarchive.net/U-570Plate11.htm


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 08:41
Tore, one off-topic question related to the high pressure compressed air system. In general, compressed air flasks are connected using "star topology" - with high pressure air distributor as central/control hub. With this air distributor are also connected air compressors (even with two lines - one primary and one backup/secondary).


When there was a need to recharge air flask, after starting compressors, were all air banks filled at the same time or were they filled one after another?
And, when rebuilding air supply, were both compressors running?


http://uboatarchive.net/U-570Plate11.htm (http://uboatarchive.net/U-570Plate11.htm)


--
Thanks, regards
Maciek

Maciek.
We normally filled one or two airvessels simultaneously. You wouldn`t operate with many empty many airvessels unless in emergency. Which means normally you took the sub up to periscopedepth (14- 11 meters) and the blew the tanks carefully until you were semi surfaced, starting the diesels and emptied the tanks by exhaust gaspressure.
In this way we had a low airconsumption. We very seldom  used more than one compressor mostly the E- compressor.
There are always exception though, in those cases it is an advantage to use the "star topology". Once we filled the main airduct to the diesel as the main inletvalve in the towercasing was open when diving, luckily the inletvalve in the engine room  was shut. However we were some 5-6 tonnes too heavy and had a quick descend, blowing all the tanks all the way using a tremendous amount of air before we finally stopped at 107 meters. When you then surface you shoot up like a rocket propelled by the expanding air in the tanks and have a spectacular surfacing with a lot of splashing. Then we had to run two compressors, this is the reason why you always want to have full airvessels. It is not the way to surface though.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 11:03
Simon.
Mainvents fuel/ ballasttanks 2&4.
I had a closer look at the mainvents inlet to the fuel/ ballast saddle tanks 2 port and stb. compairing in it with a GA drawing of 1943 and adjusting it to approximately to your scaledrawing. When using the aft  battery hatch as you use as the fixed point, it looks to me that your drawing has the mainvent inletpipe about 650-750 mm further forward than on the GA drawing.
See drawing below.
Tore

Hi Tore

In December 2009 I noted that two plans had illustrate the aft Battery Hatch in different location. After doing a little more research on why the move the aft battery hatch. I believe they move it for the 3.7cm FlaK and the quadruple 2cm L38/43 U Flak gun support for the lower Wintergraten. I believe they did this for all Type VIIC/41 or any Type VIIC that had a lower Wintergraten with these big guns on.

http://models.rokket.biz/index.php?topic=106.msg5416#msg5416 (http://models.rokket.biz/index.php?topic=106.msg5416#msg5416)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 11:29
Simon.
Indeed substantial drawing work. A detail with regard to the saddletanks. I guess fwd and aft of the conningtower area the saddletanks have a sharp bend towards the pressurehull which facilitates the pipeconnections to the tanks, see drawing below. I don`t have a good picture of the casing deck in this area but I guess the deckhatches would give an indication of the location for the various deckoperated valves.
Tore

Tore,

The angle between the saddle tanks and the pressure hull is not as abrupt in the mid section as people think. Here a extremely rare view of U-995 that show you the angle between the saddle tanks and the pressure hull.

From the photo below, you can see why I angle the pipes into saddle tanks and in the foreground you can see the remains of the main vents :'(

(http://img594.imageshack.us/img594/3509/type7ccrawlspaceunderde.jpg)

(http://imageshack.us/a/img827/5474/new1dw.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 12:27

Simon you are Right about the conningtower area, but just aft and fwd (frame55) of the saddeltanks have a sharp bend. Se pictures below showing the saddletanks joining the pressurehull forward and aft of conningtower of KNM Kaura. I guess you can just see the beginning of the bend aft of the conningtower on your picture as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 12:38
Simon.
Mainvents fuel/ ballasttanks 2&4.
I had a closer look at the mainvents inlet to the fuel/ ballast saddle tanks 2 port and stb. compairing in it with a GA drawing of 1943 and adjusting it to approximately to your scaledrawing. When using the aft  battery hatch as you use as the fixed point, it looks to me that your drawing has the mainvent inletpipe about 650-750 mm further forward than on the GA drawing.
See drawing below.
Tore

Hi Tore

In December 2009 I noted that two plans had illustrate the aft Battery Hatch in different location. After doing a little more research on why the move the aft battery hatch. I believe they move it for the 3.7cm FlaK and the quadruple 2cm L38/43 U Flak gun support for the lower Wintergraten. I believe they did this for all Type VIIC/41 or any Type VIIC that had a lower Wintergraten with these big guns on.

http://models.rokket.biz/index.php?topic=106.msg5416#msg5416 (http://models.rokket.biz/index.php?topic=106.msg5416#msg5416)

Simon very interesting I thougth the 1943 GA with snortmast was about the latest VIIC/41 version, but I guess modifications was an ongoing thing to the bitter end.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 13:01

Simon you are Right about the conningtower area, but just aft and fwd (frame55) of the saddeltanks have a sharp bend. Se pictures below showing the saddletanks joining the pressurehull forward and aft of conningtower of KNM Kaura. I guess you can just see the beginning of the bend aft of the conningtower on your picture as well.
Tore

I have always found this area of the u-boat hard to draw, the saddle tanks/pressure hull, saddle tanks shape & the wooden deck shape. I have never found any real measurement in any of these areas. So it very hard for me to drawing accurate and I have to draw by
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 13:22
Tore,

Here a lot better alignment of the angle between the saddle tanks and the pressure hull. The port saddle tank is the old drawing and the starboard is new alignment of the saddle tank. I think it much better :)

(http://img21.imageshack.us/img21/4324/new1nq.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 13:27
Tore, do you have any drawings/pictures of the exhaust outlet control valves? I know that this area is very complex and I would love to add some of this detail.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 13:33
Yes Simon.
Having checked my drawings, I guess the sharp edge goes from aft all the way up to frame 32, then rounded at the tower about 9 meters and continues as sharp edge from frame 51 and forward.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2012, 13:36
Tore, do you have any drawings/pictures of the exhaust outlet control valves? I know that this area is very complex and I would love to add some of this detail.
Simon
Do you mean the main exhaustvalves with grinders etc?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2012, 17:43
Yes, any pictures or drawing of the outside.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 00:26
Simon
Main exhaustvalve system.
I am afraid I don`t have much pictures, but I guess we have to work us through the system from the main engine outlet to the silencer. In that case it might be better to comment on what you got based on your present drawings and possible photos and then to find out the details as we have done before. In the meantime I keep looking for details on my end.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2012, 01:41
I only have two photo's from this area of the boat, very very rare to find photo's of this part of the boat. Maybe Maciek has a few pictures?

These are from U-250

(http://imageshack.us/a/img7/9803/new2or.jpg)

(http://imageshack.us/a/img585/3086/new1hn.jpg)

http://www.town.ural.ru/ship/ship/tc14.php3 (http://www.town.ural.ru/ship/ship/tc14.php3)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 13:37
Simon.
Main exhaust system.
You are right  there are not much pictures or drawings to find on the  subject. The system consist of an inboard exhaustvalve in a watercooled housing going through the pressurehull. The valvedisc has a wormdrive connection for rotating the valvedisc ( grinding ) which is operated from the engineroom by hand, and a wheel for shutting the valve. You can find a picture on the U historia webside. On one side you see a square shaftend protruding out of the housing , that is the connection for handturning of the wormdrive. After the inboard valve the watercooled pipe makes a bend towards aft having a branch off pipe going forward to the ballast tank blowing panel in the controlroom and to the snortmast, I`m sure you know all about that, valves and pipejoining etc. There is an outer main exhaust valve  pretty much the same as the inboard valve but the rotation ( grinding) of the valvedisc is done by pneumatic motor having the worm drive spindle through the pressure hull. The valve is shut by a handwheel in the engineroom up under the pressure hull. On the bad photo and drawing below I have tried to indicate the components. The outer exhaustvalve is used for adjusting  the exhaust pressure in the ballast tank during exhaustblowing. After the outer valve the pipe turns into a silencer which from outside look like a watercooled barrel and the flanged to a smaller barrel which is a spark arrestor before going through the casing side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 13:53
Simon.
Outer exhaustpipe.
I guess I should add that on the U historia picture you`ll see 3-4 drainpipes which drain the exhaustpipe both from the space between the outer and inner exhaustvalve as well as after the inner valve. These drains were frequently used and ended up in a funnel box at the lower aft engineroom bulkhead, in fact I believe together with the coolingwater drainage from the outlets of the engines as we discussed previously. On the picture you will see a bigger pipe connected, I believe this is the direct engine coolingwater pipe connection. See coolingwater sketch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2012, 14:02
Tore, when I was reading your post and see the words "The system consist of an inboard exhaustvalve in a watercooled housing going through the pressurehull." I just remember I have a few more pictures  :) :)

These are of U-534 a Type IX.

(http://imageshack.us/a/img607/2984/new2my.jpg)

(http://imageshack.us/a/img818/1341/new1hu.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2012, 14:06
Simon.
That may be.  I think I have seen a drawing of the compensating box in the bottom of the saddletank. See below,  I made a rough pencil sketch indicating where to look for it you have more materials to look into than me.
Tore

This could be that pipe on the U-534

(http://img26.imageshack.us/img26/9379/new3h.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2012, 14:17
Simon
Fuel compensating saddle ballasttanks
The valve b is a valve only in use when you select the mode you want to use the saddletanks,as fuel tanks or ballasttanks. It is a double seated valve with only two positions  either in direct contact with the head tank in the conningtower when the saddletank is used as fueltank or in direct contact with the sea when the saddletank is used as ballasttank. I believe it is controlled from outside the pressurehull under the casingdeck as it is not often used. I think it is a hatch in the deck for access.
Tore


Thanks Tore.

I have checked all my photo's and checked dive videos and found no evidence of these pipes. So this morning I started checking deck hatches and I think I can location the positions they enter the saddle tanks using the hatches. I will use this as my glide for the drawing.

Do you think the open end to the sea would have a pipe screen over the end to stop sea weeds etc entering the system?

I think I may have an explanation why I can not found any evidence of these pipes. I previous imagine those pipes would run just above the pressure hull, but now I believe there is not enough room, so the Germans run those pipes just under the wooden deck. As both the decking of U-352 and U-1021 are gone, this is why I can not found these pipes in the dive videos.

I had forgotten I had these photo's. Here are the small pipes running just under the decking :)

(http://img836.imageshack.us/img836/5656/new4is.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 14:42
Tore, when I was reading your post and see the words "The system consist of an inboard exhaustvalve in a watercooled housing going through the pressurehull." I just remember I have a few more pictures  :) :)

These are of U-534 a Type IX.

(http://imageshack.us/a/img607/2984/new2my.jpg)

(http://imageshack.us/a/img818/1341/new1hu.jpg)
Well Simon I guess that`s it. I presume the VIIC and IX were pretty much alike on this detail. The cooling pipebends follow the same pattern as previously discussed, bypassing the flanges and other coolinwater jacket obstructions. Apart from these pipes every detail is hidden inside the pipe and housing.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 15:07
Simon.
That may be.  I think I have seen a drawing of the compensating box in the bottom of the saddletank. See below,  I made a rough pencil sketch indicating where to look for it you have more materials to look into than me.
Tore



This could be that pipe on the U-534

(http://img26.imageshack.us/img26/9379/new3h.jpg)
Simon. Interesting detail, it certainly could be the box, I only miss the pipe out of the box. The idea was to have a buffer preventing contamination into the compensating system. Howewer the most important pipe for that was the fueloil venting pipe  which ended some 10 cm from the bottom of the ballast/fueltank. When fuelling, the ventcock was open and a guy watched the water coming out and stopped the fuelling when he discovered fuel coming out, but as the pipe ended 10 cm above the tankbottom you could never force fuel into the compensatingpipe as the fuel was flowing through the ventpipe leaving some 10 cm of water in the tankbottom saving the compensating system. This was  before pollution and environment questions was a topic. Anyhow see to it that your fuel ventingpipe is not leading all the way to the bottom ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2012, 23:38
Simon.
Compensating expansionbox.
As to my yesterdays post I have given it a second thought. I believe the device and connecting pipe on the picture is too small for being the box. Estmating the capacity of the tank to be some 12 tonnes of fuel I guess it should have a volume about 150-200 liters ( almost an oilbarrel).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2012, 00:05
Simon.
Reverting to your drawing of the main ventconnection for saddle fuel/ballast tank 4 stb.and port. The intermediate valve is a blocking gatevalve for each saddle fuel/ballast tank permanently shut when in fuelmode. In view of a possible risk for somebody to ship this valve, I believe the wheel was removed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Dec , 2012, 01:31
Trimvalve.
We are frequently missing a cross section drawing of the various components to get a better understanding how the various systems works, Simon has provided us with a genuine cross section of the doubleseated valve which clearly demonstrate the working of the valve. Although I believe the photo is from a IX, I guess it is the same for VIICs.
On the unusual photo below I believe you see a cut through of the aft port side of the control room showing the trimpump with the doubleseated trim valve.  The double seated valve could have only two positions, directing the water from fwd to aft or aft to fwd trimtanks. Allthough the display gives a first class demonstration of the working, it is an expensive way of showing it. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Dec , 2012, 20:38
Simon.
Reverting to your drawing of the main ventconnection for saddle fuel/ballast tank 4 stb.and port. The intermediate valve is a blocking gatevalve for each saddle fuel/ballast tank permanently shut when in fuelmode. In view of a possible risk for somebody to ship this valve, I believe the wheel was removed.
Tore

Fixed. Thanks, Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Dec , 2012, 21:29
http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0 (http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0)

Tore, a while ago we had a discuss about fuel filter and which one was a original fuel German filter.
 
Would you go for port or starboard?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Dec , 2012, 23:21
http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0 (http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0)

Tore, a while ago we had a discuss about fuel filter and which one was a original fuel German filter.
 
Would you go for port or starboard?

Simon.
I would go for port, but that`s pure guesswork from my side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2012, 07:41
Simon.
Reverting to your drawing of the main ventconnection for saddle fuel/ballast tank 4 stb.and port. The intermediate valve is a blocking gatevalve for each saddle fuel/ballast tank permanently shut when in fuelmode. In view of a possible risk for somebody to ship this valve, I believe the wheel was removed.
Tore
Simon.
The blocking gatevalve is a special design as can be seen on the picture below. When open it retracts the disc ( wedge) 100% in the valve housing on top of the valve which mean the valvehousing is very high. The advantage is that when open it has a full flow passage as the valve disc is out of the way. For your drawing it means that the valvehousing looks like the photo below.

Fixed. Thanks, Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Dec , 2012, 14:32
Simon.
Reverting to your drawing of the main ventconnection for saddle fuel/ballast tank 4 stb.and port. The intermediate valve is a blocking gatevalve for each saddle fuel/ballast tank permanently shut when in fuelmode. In view of a possible risk for somebody to ship this valve, I believe the wheel was removed.
Tore
Simon.
The blocking gatevalve is a special design as can be seen on the picture below. When open it retracts the disc ( wedge) 100% in the valve housing on top of the valve which mean the valvehousing is very high. The advantage is that when open it has a full flow passage as the valve disc is out of the way. For your drawing it means that the valvehousing looks like the photo below.

Fixed. Thanks, Tore.

I have update the valves to more closely match the valve found on U-534.

(http://img35.imageshack.us/img35/5474/new1vg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2012, 14:52
Simon.
Excellent!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Dec , 2012, 21:50
Hi Tore

Here a update on the fuel system. I choose not to add the long fuel supply line in the top view as it cover up to much great detail so you can see the pipe opening at the forward end of the engine.


(http://imageshack.us/a/img528/4324/new1qzx.jpg)

(http://imageshack.us/a/img194/60/new2fi.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2012, 00:46
Simon.
It looks good. Realizing you no doubt are aware of the details I nevertheless mention:
As previously discussed the fuelcollecting box I believe should be almost the size of the hight oft the camshaft cover and the endcover of the exhaustmanifold has a relief valve. See picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2012, 01:40
Fuel/ballast saddletanks gatevalve.
As you see on the photo of U 534, the gatevalve obviously was shipped from another location, hence the linkage seen on the picture. However as
U 534 is IX we cannot assume the same on a VIIC. I guess till you have evidence otherwise it is better to leave the valve as you have drawn it. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2012, 06:30
Simon.
Main drain valve.
From the amazing photos of U 534 is another component revealed, the details of the remote controlled main drain bottom valve. As can be seen from the photo below the valve is placed at the very bottom of the bilge, has as flanged suction pipestub and a rodconnection to the handle having a bevelgear connection to a shaft going through the bulkhead. The bevelgear is probably not applicable to the VIICs though.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2012, 10:31
Fuel/ballast saddletanks gatevalve.
As you see on the photo of U 534, the gatevalve obviously was shipped from another location, hence the linkage seen on the picture. However as
U 534 is IX we cannot assume the same on a VIIC. I guess till you have evidence otherwise it is better to leave the valve as you have drawn it. ;)
Tore

Hi Tore

I also noted this linkage yesterday while updating my drawing. I search the few Type IX's plans I have to see if I could found a reason why they added a linkaga. I don't have the detail plan to tell why :(

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2012, 11:04
Simon.
Main drain valve.
From the amazing photos of U 534 is another component revealed, the details of the remote controlled main drain bottom valve. As can be seen from the photo below the valve is placed at the very bottom of the bilge, has as flanged suction pipestub and a rodconnection to the handle having a bevelgear connection to a shaft going through the bulkhead. The bevelgear is probably not applicable to the VIICs though.
Tore

Hi Tore
 
Great spotting!
 
I will update my drawing to more closely match the photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2012, 11:54
Simon
Your drawings are really going to be a proper documentation with the painstaking patience and work you put into the accuracy of the details. There is an explanation and a reason why the details look as they do and that a valve is not just a valve placed at random,  your drawings shall tell the story.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Dec , 2012, 18:40
Simon.
Crankcase doors.
Now we are really going into details, but I happened to notice some small discrepancies on your bedplate/ crankcasedoors. As you see on the picture below, the stiffening knees between the crankcasedoors are ending a bit higher up between the doors and the narrow end cover up forward is protruding further down than the ordinary crankcase doors. The narrow frontcover is just a plate. Crayzy details hardly noticed by anybody but mee.  ;D
Tore


(http://img254.imageshack.us/img254/3823/new1ja.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2012, 01:49
Simon
Bedplate
Very good! This is really a ridiculous detailremark, But have you noticed the stiffening knees between the crankcasedoors are a bit higher than the others? See below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2012, 02:17
Simon
Bedplate
Very good! This is really a ridiculous detailremark, But have you noticed the stiffening knees between the crankcasedoors are a bit higher than the others? See below.
Tore

Tore, I believe this is a small different between the F46a6p and the F46a9p. I believe they are all the same size on the F46a6p. I initially base my drawing from the photo of the F46a9p and today while updating my drawing I check the original German drawings and compare it with the photo of the F46a9p and I noted a few little differences.   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2012, 04:15
Simon.
I guess you are right, I checked the KNM Kauras bedplate and the stiffening knees are all on the same level.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 13 Dec , 2012, 06:35
Simon -
I really love the galvanized metal texture you pulled off on the image above! Well Done! (http://img35.imageshack.us/img35/5474/new1vg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2012, 11:24
Tore, a couple of qections about the head tank.
http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2012, 14:37
Simon
Head tank.
The head tank is not a storage tank but act like a head buffer where the cooling water from the outboard exhaustsystem enters the fuelcompensating system. I would guess a capacity of something between 25 max. 75 liters, it is situated in the old tower casing. It is in direct contact with the sea, while submerged, via a swan neck pipe on the top. It should give a head at the day/setlingtank up under the pressure hull in the engine room of about 2-3 meter.
The filling of the compensating system is done by the ME cooling waterpumps.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Dec , 2012, 16:41
Fuel oil compensating system

Hi Tore/Maciek

I am trying to track down this section of pipe that runs into FO Collecting Tank (Fig. 1.), where do you think I would found the valves f1 and f2 so I can location the starting postion of the pipe?

(http://img268.imageshack.us/img268/7412/new2br.jpg)
Fig. 1. http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Dec , 2012, 16:57
Simon.
Fuel drain.
The main fuel drain on the engine goes along the engine just about where the cylindercovers meets the cylinder block, it collect the spill from each cylindercover via funnels and leads to the forward of the engines joins the drain (yellow) from the knifefilter before it drain into the fuel draintank. It is no T piece where the fuel filter enters the maindrain, just a welded branch with threads for the connection.
Tore

(http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=3085;image)


Fuel drain lines (Violet-Red-Violet) into FO Collecting Tank

(http://img72.imageshack.us/img72/2586/new4cg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2012, 00:25
Simon.
Looks fine :) . As you are aware of, the collecting tank has a few other connections, the venting and the suction pipe to the hand coolingwater pump indicated on the drawing below. I don`t know for sure but I believe it is a cast pipefitting on the top of the tank collecting all the four drainpipe connections.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2012, 07:19
Hi Simon
I am trying to track down this section of pipe that runs into FO Collecting Tank (Fig. 1.), where do you think I would found the valves f1 and f2 so I can location the starting postion of the pipe?


I was not able to locate this valve in Diesel Engine Room. However, it maybe helpful - similar valve for the internal fuel oil tank 2i is located in control room, near the helmsman station:
(http://img401.imageshack.us/img401/1407/overpressurevalve.jpg)


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2012, 07:21
Simon.
Fuel collecting tank
Unfortunately I do not have pictures of all the components and I guess the systemsketch is not very complete. To start with the inboard venting and levelcontrol of fuel saddletanks 2 port and stb. see sketch below. If you look at the last photo of the fueloil system page on the U historia webside, you will see two L shaped handles up under the pressurehull on port and stb.side, these are the boardvalves for the inboard venting and levelcheck of no 2 fuel saddletanks. They are marked 7 on the photo and the pipe 8. I guess they have exchanged the L handles as the 2nd valve has the ball and the board valve not.  Hopefully you have better photos than me to localize the details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2012, 09:56
Simon.
As Maciek has been able to establish, the f1 and f2 valves is a double valve in one housing, it is an overpressure and  underpressure reliefvalve. I have not been able to localize it in the engineroom either. The confusing part of it is that the valve is located in the water compensating system which is with great effort designed so fueloil is not entering the system. In the fueltank, the compensatingpipe outlet is 10 cm below the ventingpipe and in a compensatingbox in order to prevent any fuel entering the system. The venting pipe is supposed to get a very small amount of fueloil when fuelling and the tank gets filled up . I believe the diagram I showed in my previous post is probably more reliable. I really don`t see why the drain from the reliefvalve in the seawater compensating system should end up in the fuelcollecting tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 11:23
Simon.
Fuel collecting tank
Unfortunately I do not have pictures of all the components and I guess the systemsketch is not very complete. To start with the inboard venting and levelcontrol of fuel saddletanks 2 port and stb. see sketch below. If you look at the last photo of the fueloil system page on the U historia webside, you will see two L shaped handles up under the pressurehull on port and stb.side, these are the boardvalves for the inboard venting and levelcheck of no 2 fuel saddletanks. They are marked 7 on the photo and the pipe 8. I guess they have exchanged the L handles as the 2nd valve has the ball and the board valve not.  Hopefully you have better photos than me to localize the details.
Tore

I was able to found the starboard funnel section :) :)    Have no idea the alignment and route the pipe takes once under to the floor, will have a educated guess on that :(

Tore, why have a open section within this system, was it so you can have a visual check? If so, why would you want to have a visual check?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 11:28
Simon.
Fuel collecting tank
Unfortunately I do not have pictures of all the components and I guess the systemsketch is not very complete. To start with the inboard venting and levelcontrol of fuel saddletanks 2 port and stb. see sketch below. If you look at the last photo of the fueloil system page on the U historia webside, you will see two L shaped handles up under the pressurehull on port and stb.side, these are the boardvalves for the inboard venting and levelcheck of no 2 fuel saddletanks. They are marked 7 on the photo and the pipe 8. I guess they have exchanged the L handles as the 2nd valve has the ball and the board valve not.  Hopefully you have better photos than me to localize the details.
Tore

Tore, on the port side there is a gage tank, what is it, what does it look like, what is it for?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2012, 11:39
Simon.
I don`t believe the visual check is the main thing, you could better have a sigthglass. Generally a breach in the pipeline (funnel) is to eliminate a possible undesired syphoning effect in the system.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2012, 11:41
Quite a different topic - I have just noticed, that in the aft part of the control room, where should be located the hand wheels for the head valves of the diesel engine air induction trunk, ventilation air intake and exhaust, one of these valves - ventilation air intake is missing:
(http://img19.imageshack.us/img19/6198/ventilationhullvalvesco.jpg)
http://www.kubische-panoramen.de/index.php?id_id=5378&p=i (http://www.kubische-panoramen.de/index.php?id_id=5378&p=i)


It looks like after installing Schnorchel, the intake of the ventilation trunk was blanked. Moreover, the foot valve closing this trunk in the diesel engine room is still in place. I suppose, it was left to allow drain the trunk after accidental flooding.
Generally, such arrangements is like ventilation system on the "Schnorchel boats" - U-Boats type XXI and XXIII.




--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 11:46
Simon.
I don`t believe the visual check is the main thing, you could better have a sigthglass. Generally a breach in the pipeline (funnel) is to eliminate a possible undesired syphoning effect in the system.
Tore

Thanks Tore! I learn something new every day  ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 11:50
Quite a different topic - I have just noticed, that in the aft part of the control room, where should be located the hand wheels for the head valves of the diesel engine air induction trunk, ventilation air intake and exhaust, one of these valves - ventilation air intake is missing:
(http://img19.imageshack.us/img19/6198/ventilationhullvalvesco.jpg)
http://www.kubische-panoramen.de/index.php?id_id=5378&p=i (http://www.kubische-panoramen.de/index.php?id_id=5378&p=i)


It looks like after installing Schnorchel, the intake of the ventilation trunk was blanked. Moreover, the foot valve closing this trunk in the diesel engine room is still in place. I suppose, it was left to allow drain the trunk after accidental flooding.
Generally, such arrangements is like ventilation system on the "Schnorchel boats" - U-Boats type XXI and XXIII.




--
Regards
Maciek

Maciek, great found! I also noted this last week when I was updating my Schnorchel drawing and was wondering what it was. I was going to ask you what it was ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 12:08
Simon.
Fuel collecting tank
Unfortunately I do not have pictures of all the components and I guess the systemsketch is not very complete. To start with the inboard venting and levelcontrol of fuel saddletanks 2 port and stb. see sketch below. If you look at the last photo of the fueloil system page on the U historia webside, you will see two L shaped handles up under the pressurehull on port and stb.side, these are the boardvalves for the inboard venting and levelcheck of no 2 fuel saddletanks. They are marked 7 on the photo and the pipe 8. I guess they have exchanged the L handles as the 2nd valve has the ball and the board valve not.  Hopefully you have better photos than me to localize the details.
Tore

Think I now found the port side funnel section, but not a 100% sure ???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 12:18
Fuel oil compensating system

Hi Tore/Maciek

I am trying to track down this section of pipe that runs into FO Collecting Tank (Fig. 1.), where do you think I would found the valves f1 and f2 so I can location the starting postion of the pipe?

(http://img268.imageshack.us/img268/7412/new2br.jpg)
Fig. 1. http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)

I think this valve is very near or behind the auxiliary lubrication oil pump on the port side of the boat. This is why I believe we can not found it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Dec , 2012, 16:32
Fuel Drain Lines (Violet-Red-Violet) into FO Collecting Tank

(http://img525.imageshack.us/img525/1492/new3v.jpg)
Fig. 1. Fuel Drain system.

(http://img834.imageshack.us/img834/4619/new4g.jpg)
Fig. 2. All system (Lots of pipes and vlaves ;D)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2012, 00:34
Simon.
So far so good, but quite a lot remains and it is so easy to be confused. I guess the system layers is the solution as well as the check and completion of each separate system before putting it in the final drawing. The complete spaghetti pot shall be formidable, almost impossible to understand but the satisfaction of knowing it is correct is the reward. Keep going on the same track on your amazing project.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2012, 01:12
Simon.
Coolingwater crossover.
Looking at your above system drawing showing the coolingwater crossover, I came to think about the execution of the crossover shut off valves. All 5 are gatevalves which we discussed previously, I seem to remember vaguely 3 of the valves (center) were operated by a T bar from a hatch in the floorplating that would mean no handle wheels. On U-995 the aluminium deckplating covers all hatches but if you have evidence otherwise you should ignore my frail memory, if not, it might be worth while to check.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2012, 03:54
Changing the topic a bit. We discussed previously the board seavalve having more smaller direct connections and I just happen to see the regulating tank sea intake valve in the controlroom next to the main drainpump. The valvehousing is indeed equipped with two extra direct seaconnections, one for weedblowing and another for the evaporator. Note the low connections on the valvehousing. The small connection are in direct seaconnection even if the main valve is shut.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Dec , 2012, 10:12
Simon.
So far so good, but quite a lot remains and it is so easy to be confused. I guess the system layers is the solution as well as the check and completion of each separate system before putting it in the final drawing. The complete spaghetti pot shall be formidable, almost impossible to understand but the satisfaction of knowing it is correct is the reward. Keep going on the same track on your amazing project.
Tore

Yes, you can correct without layers it would be a nightmare to keep track and to make changes to separate systems or sub-systems. Most system can be added to a single layer, however, it can be a nuisance if a pipe gone under or over another pipe on different layer.

It would really like to be able to add every systems within the engine drawing, but I think this will impossible with the current information we have. If I can add 80% of them I would be happy.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Dec , 2012, 11:11
Simon.
Coolingwater crossover.
Looking at your above system drawing showing the coolingwater crossover, I came to think about the execution of the crossover shut off valves. All 5 are gatevalves which we discussed previously, I seem to remember vaguely 3 of the valves (center) were operated by a T bar from a hatch in the floorplating that would mean no handle wheels. On U-995 the aluminium deckplating covers all hatches but if you have evidence otherwise you should ignore my frail memory, if not, it might be worth while to check.
Tore

I rechecked the U-570 Design Books and you are correct. I will update my drawing.

I was checking some of my u-boat books and I came across this picture from U-Boote Crews: 1939 - 1945 by Jean Delize, it shows two 'T' handles hatches within the floor plating.

(http://img703.imageshack.us/img703/7908/new1qg.jpg)
U-Boote Crews: 1939 - 1945 by Jean Delize
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2012, 11:37
simon.
I guess this is the thing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 16 Dec , 2012, 12:13
Hi


Take a look at the floor in the engine room of U-505 - there are a lot of these hatches:
http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Dec , 2012, 12:24
Hi


Take a look at the floor in the engine room of U-505 - there are a lot of these hatches:
http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html (http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html)


--
Regards
Maciek

Thanks Maciek!

I am starting to think that they used them a lot, this would make sense.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Dec , 2012, 13:07
'T' handles hatches within the floor plating

(http://imageshack.us/a/img341/7719/new3p.jpg)

(http://imageshack.us/a/img829/307/new4be.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2012, 23:44
Simon.
This seems to be pretty close to how I remember it. The pipe systemsketch indicates indeed the decklevel extension of the three valvespindles. The deckplates were as far as I remember fixed to the supports by screws and was rather cumbersome and timeconsuming to open.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2012, 03:59
Seawater crossovervalves.
Below is Simons photo of U 534 showing the extensionrods of the valves. I believe the valves were of quite similar execution on the VIICs. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Dec , 2012, 11:21
Seawater crossovervalves.
Below is Simons photo of U 534 showing the extensionrods of the valves. I believe the valves were of quite similar execution on the VIICs. 
Tore

Tore, great found!!  :D :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Dec , 2012, 12:59
Seawater crossovervalves.
Below is Simons photo of U 534 showing the extensionrods of the valves. I believe the valves were of quite similar execution on the VIICs. 
Tore

Updated the valve this morning.

(http://img20.imageshack.us/img20/7034/uboatpiping.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Dec , 2012, 13:09
Hi Tore/Maciek

Do you think were was either words or symbols on the top surface of the 'T' handles hatches within the floor plating to show the way to open/closed the valve? Something like below.
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2012, 14:17
Simon.
Sorry I don`t remember so my advice is based on a marine engineers assumption. Signs telling which way to turn to open or shut an ordinary valve would be superfluous in an engineroom. I guess a sign would rather indicate which valve the rod belonged to.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Dec , 2012, 14:20
Simon.
Sorry I don`t remember so my advice is based on a marine engineers assumption. Signs telling which way to turn to open or shut an ordinary valve would be superfluous in an engineroom. I guess a sign would rather indicate which valve the rod belonged to.
Tore

Thanks :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 01:37
Simon.
Crossovervalves.
A small detail. I guess the valve spindles are a bit longer and it might be an universal joint between the spindle and the extension rod if you can figure out the details on the photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Dec , 2012, 02:04
Simon.
Crossovervalves.
A small detail. I guess the valve spindles are a bit longer and it might be an universal joint between the spindle and the extension rod if you can figure out the details on the photo below.
Tore

I think you are correct, Tore. I rechecked my photo's and it look like a universal joint top & bottom of the spindle. I wonder if the Germans did this allow a little bit of movement when under depth charging ???

I just checked the length of my spindle and it was 535 mm I would not imagine then would be to long, but I do not know for sure.
 
I will update my drawing again in the morning ;D

I was thinking today it would be great to see a current photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 04:40
Simon.
I believe the connection rods were supported only in the upper upper part to the floorplates which as not a very stable support and could create a bend, of course depthcharging could make it worse.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 05:08
Simon
Valvespindle.
I guess we are talking about different spindle. What I mean is the spindle tap coming out of the valvehousing. May be it should be about 70-80 mm.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 07:11
Simon
I guess a part of the confusion is that on the top of the valvehousing it is a small casing for the spindle stuffingbox having a yoke which is pressing the packing down in the housing by two nuts and the spindle is some 70mm above that stuffingbox before connecting to the universal coupling.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Dec , 2012, 11:33
Tore, how does this look like now?

(http://img846.imageshack.us/img846/7034/uboatpiping.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Dec , 2012, 12:08
Tore, do you know if the wooden deck on KNM Kaura was replace ? Or was it the original German decking.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 14:38
Tore, how does this look like now?

(http://img846.imageshack.us/img846/7034/uboatpiping.jpg)
Simon this will do ok!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2012, 14:43
Tore, do you know if the wooden deck on KNM Kaura was replace ? Or was it the original German decking.
Simon.
I guess some of the deck was partly renewed, particulary in the area of the wintergarden and the storage containers forward of the snortmast.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Dec , 2012, 16:07
Hi Tore

Here a total realignment of the piping of the Fuel oil compensating system. Now to start on the piping inside the engine room ;D

(http://img203.imageshack.us/img203/6311/new7g.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2012, 01:40
Hi Simon.
It seams to be very good. Seeing the hatch I just came to remember an intricate system of rods connecting the steelhatches to the wooden deck hatches so they could be opened in one operation. Anyhow this system was used for the galley hatch and fwd torpedo loadinghatch which were crewaccesses while alongside. Pictures below, on one of the photos you can see a guy operating one of the external valves from the deck by the T bar.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Dec , 2012, 11:11
Hi Tore

I am trying to locate the 'FO Feed Pump' line, do you think I have located the corrent line in the photo below?

UPDATED: Tore, now after taking a 2nd look, this the FO Feed Pump line the line that runs along the the engine?

(http://imageshack.us/a/img839/4989/new3xav.jpg)
Source: http://www.uboatarchive.net/U-570Plate9.htm (http://www.uboatarchive.net/U-570Plate9.htm)

(http://imageshack.us/a/img94/2794/new2by.jpg)
Source: U-995 DVD http://www.uboataces.com/u995.shtml (http://www.uboataces.com/u995.shtml)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Dec , 2012, 11:22
Hi Simon.
It seams to be very good. Seeing the hatch I just came to remember an intricate system of rods connecting the steelhatches to the wooden deck hatches so they could be opened in one operation. Anyhow this system was used for the galley hatch and fwd torpedo loadinghatch which were crewaccesses while alongside. Pictures below, on one of the photos you can see a guy operating one of the external valves from the deck by the T bar.
Tore

Thanks for the pictures and information.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2012, 12:45
Simon.
If you mean the enginedriven fueloil boosterpump which is fed from the overhead daytank remember the fueloil system sketch is showing the MAN execution and the GW layout has the fuel boosterpump forward as previously discussed. The suction line from the daytank is the dominant black pipe going along the side of the engine and is not shown on the sketch. The pipe you refer to (violet arrow) is the enginetop drain pipe and is almost hidden going along the engine at the level where the cylindercovers meets the cylinderblock.See pictures below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2012, 13:21
Simon.
I`m not sure if everything is quite clear so here is an additional sketch which I hope might make it a bit more understandable.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Dec , 2012, 13:33
Thanks Tore  :) :)

This helps heaps! Will update my drawing tomorrow, working on new engine covers this morning.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Dec , 2012, 13:44
Tore, the cover bolts, should I have them bolt head or nut side out?
 
As on U-995 they are allsorts ::) http://www.kubische-panoramen.de/index.php?id_id=5376&p=i (http://www.kubische-panoramen.de/index.php?id_id=5376&p=i)

(http://img542.imageshack.us/img542/2364/new3t.jpg)

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2012, 15:37
Simon.
Of course I don`t remember but according to a photo of U 178   the nuts  were out. See picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Dec , 2012, 17:28
Simon.
Of course I don`t remember but according to a photo of U   the nuts  were out. See picture below.
Tore

Thanks :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2012, 23:58
Simon.
I just noticed somehow in the reference to the photo the U number is missing. The photo is from the engine room of U 178 just for the record as appropriate for all scientific papers ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Dec , 2012, 11:08
Hi Tore

I was able to follow the FO drain line (below and orange), however, this is different than that you posted :o I am following the worng line ???

(http://img15.imageshack.us/img15/3947/new1pks.jpg)

(http://imageshack.us/a/img688/7800/p1100225t.jpg)
(http://imageshack.us/a/img18/8756/p1100226f.jpg)
(http://imageshack.us/a/img831/5718/p1100227.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Dec , 2012, 11:24
Simon.
Of course I don`t remember but according to a photo of U 178   the nuts  were out. See picture below.
Tore

New Camshaft  covers, The old covers can be seen in the post above.

(http://img6.imageshack.us/img6/6683/new2kp.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Dec , 2012, 12:33
The other day when updating the Camshaft covers I had to used the side view to make sure I had the correct alignment. So I update a little more of my side view :)

(http://img35.imageshack.us/img35/1259/new5it.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2012, 12:43
Hi Tore

I was able to follow the FO drain line (below and orange), however, this is different than that you posted :o I am following the worng line ???

(http://img15.imageshack.us/img15/3947/new1pks.jpg)

Simon

(http://imageshack.us/a/img688/7800/p1100225t.jpg)
(http://imageshack.us/a/img18/8756/p1100226f.jpg)
(http://imageshack.us/a/img831/5718/p1100227.jpg)

Simon.
It might be two drainpipes to the draintank, fwd and aft. I don`t have a proper photo to ascertain the lay out.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2012, 12:56
Simon.
Of course I don`t remember but according to a photo of U 178   the nuts  were out. See picture below.
Tore

New Camshaft  covers, The old covers can be seen in the post above.

(http://img6.imageshack.us/img6/6683/new2kp.jpg)
Simon
Beautiful Xmas decoration. :D  Have you noticed that only the centercover has 3 nuts whereas the 2 others have 4 ? I guess you had the correct configuration on the old drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2012, 13:07
The other day when updating the Camshaft covers I had to used the side view to make sure I had the correct alignment. So I update a little more of my side view :)

(http://img35.imageshack.us/img35/1259/new5it.jpg)
Simon.
Very good, but don`t forget  foldable step along the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Dec , 2012, 21:11
Simon.
Of course I don`t remember but according to a photo of U 178   the nuts  were out. See picture below.
Tore

New Camshaft  covers, The old covers can be seen in the post above.

(http://img6.imageshack.us/img6/6683/new2kp.jpg)
Simon
Beautiful Xmas decoration. :D  Have you noticed that only the centercover has 3 nuts whereas the 2 others have 4 ? I guess you had the correct configuration on the old drawing.
Tore

Thanks, Tore. I did not noted the number of nuts. Fixes now.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2012, 05:35
Hi Simon.
It seems to be very good. Seeing the hatch I just came to remember an intricate system of rods connecting the steelhatches to the wooden deck hatches so they could be opened in one operation. Anyhow this system was used for the galley hatch and fwd torpedo loadinghatch which were crewaccesses while alongside. Pictures below, on one of the photos you can see a guy operating one of the external valves from the deck by the T bar.
Tore

Thanks for the pictures and information.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Dec , 2012, 10:57
Tore, check out this diesel engine :o

(http://www.blogcdn.com/www.autoblog.com/media/2011/07/largest-diesel-engine.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Dec , 2012, 11:20
http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0 (http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0)

Tore, a while ago we had a discuss about fuel filter and which one was a original fuel German filter.
 
Would you go for port or starboard?

Simon.
I would go for port, but that`s pure guesswork from my side.
Tore

Found evidence that the post side fuel filters are very likely the original German filters :) :) :) :)

(http://imageshack.us/a/img854/664/new8o.jpg)
(http://imageshack.us/a/img821/6198/new9j.jpg)
(http://img841.imageshack.us/img841/9030/new11g.jpg)

http://en.wikipedia.org/wiki/Mahle_GmbH (http://en.wikipedia.org/wiki/Mahle_GmbH)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Dec , 2012, 11:39
Hi Tore

I was able to follow the FO drain line (below and orange), however, this is different than that you posted :o I am following the worng line ???

(http://img15.imageshack.us/img15/3947/new1pks.jpg)

Simon

(http://imageshack.us/a/img688/7800/p1100225t.jpg)
(http://imageshack.us/a/img18/8756/p1100226f.jpg)
(http://imageshack.us/a/img831/5718/p1100227.jpg)

Simon.
It might be two drainpipes to the draintank, fwd and aft. I don`t have a proper photo to ascertain the lay out.
Tore

Tore, there seem to be two styles of funnels, it may possibly suggest alteration to this line.

Also check my pictures and found a photo that very strong suggest that this line is collected at both the aft and stern.

Do you think both drain lines are original German, if I had to choose one drain line I would think that the forward line this the original German line.

(http://imageshack.us/a/img837/6483/new1j.jpg)
(http://imageshack.us/a/img546/3702/new2y.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2012, 12:00
Simon
Hard to say, but I should say it is original. If you have a closer look you may see the line has its highest point in the middle of the engine , where the two cyliderblocks are flanged together. From this point the forward half of the pipe inclines down forward and the other down  aft.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2012, 12:04
Tore, check out this diesel engine :o

(http://www.blogcdn.com/www.autoblog.com/media/2011/07/largest-diesel-engine.jpg)

Simon.
35 years of my life I have been working with this kind of engines. They are massive. Cylinder bore of almost 1000mm and stroke of 1800mm, a grown up man could easely stand within the cylinder :D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2012, 12:13
http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0 (http://www.360cities.net/image/submarine-u-995-machine-room#268.60,11.26,110.0)

Tore, a while ago we had a discuss about fuel filter and which one was a original fuel German filter.

 
Would you go for port or starboard?

Simon.
I would go for port, but that`s pure guesswork from my side.
Tore

Found evidence that the post side fuel filters are very likely the original German filters :) :) :) :)

(http://imageshack.us/a/img854/664/new8o.jpg)
(http://imageshack.us/a/img821/6198/new9j.jpg)
(http://img841.imageshack.us/img841/9030/new11g.jpg)

http://en.wikipedia.org/wiki/Mahle_GmbH (http://en.wikipedia.org/wiki/Mahle_GmbH)
Simon.
Nice to have confirmation my guesswork was right.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2012, 00:12
To all my readers of my mailbox.
With the picture of my farm in the wilderness, in some places we have up to 4 m of snow right now, I wish everybody happy holydays.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Dec , 2012, 13:50
Lubricating oil collecting and distributing manifold

Tore, how does this work, If you open the valve with the handle, its open and closes both valves at the same time??

(http://img13.imageshack.us/img13/8706/graphic1nv.jpg)
http://www.uboatarchive.net/U-570Plate14.htm (http://www.uboatarchive.net/U-570Plate14.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Dec , 2012, 13:53
To all my readers of my mailbox.
With the picture of my farm in the wilderness, in some places we have up to 4 m of snow right now, I wish everybody happy holydays.
Tore

Looks great! We did not get any snow for Christmas, we got +25
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Dec , 2012, 23:39
Simon.
Luboil returnpipe.
This valvechest is selecting which the luboil returntank is connected the engine. If you shut one valve the other opens, thus you have always a drain connection in the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Dec , 2012, 23:49
Simon.
We have rigth now -9 degrees C and just got 30 cm fresh snow during the nigth and pitch dark at 9 oclock a.m, if you miss the snow just come over. 5 days ago 3 passengertrains  were stuck in the snow for hours and we have already had the first avalanche killing people.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Dec , 2012, 00:37
Simon.
Luboil returnpipe.
This valvechest is selecting which the luboil returntank is connected the engine. If you shut one valve the other opens, thus you have always a drain connection in the system.
Tore

Thanks, Tore. I will update my drawing tomorrow. I have to update these pipes so I can correctly lay down the FO drain lines.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Dec , 2012, 22:24
Engine lubricating oil system

A total redraw of the pipe between the Engine lubricating oil manifold and the Collecting Tank.

(http://imageshack.us/a/img594/5479/new1kt.jpg)
(http://imageshack.us/a/img163/6913/new3so.jpg)

(http://imageshack.us/a/img191/5999/new4ol.jpg)
(http://imageshack.us/a/img853/105/new2ll.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 01:22
Simon.
As usual the drawings are first class. The luboilsystem might be a bit tricky as there are so many alternatives. It might be easier to take the system step by step, starting with the basics..
Below is a colour sketch of the basic system leaving temporarely the secondary systems out. It looks to me as if you have introduced the luboilsentrifuge systems into the luboilsystem having pipes going through the manholecovers of the luboil systemtanks.  I am not sure if the pipes were fitted on the cover. May be you should try to make a layer with the basics first and then add the other alternative systems later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 01:58
Simon.
Luboil connections main engine.
Below is a crossection drawing of the main engine showing how the internal luboil system works. A luboilpipe on the outboard side, (not interfering with the crankcase doors) leads oil through drillings in the A frames (red) to the main bearings where it goes through drillings in the crankshaft to the crankpin bearings, then down in the crankcase bottom and drains via the lowest point fore and aft to the external drainsystem. Hopefully you are able to trace the external supplypipe along the engine, unfortunately I don`t have any picture showing same.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 10:30
Simon.
As usual the drawings are first class. The luboilsystem might be a bit tricky as there are so many alternatives. It might be easier to take the system step by step, starting with the basics..
Below is a colour sketch of the basic system leaving temporarely the secondary systems out. It looks to me as if you have introduced the luboilsentrifuge systems into the luboilsystem having pipes going through the manholecovers of the luboil systemtanks.  I am not sure if the pipes were fitted on the cover. May be you should try to make a layer with the basics first and then add the other alternative systems later.
Tore

Thanks Tore, the colour map is very useful! It help me to understand and make sence of it :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 10:31
Simon.
Luboil connections main engine.
Below is a crossection drawing of the main engine showing how the internal luboil system works. A luboilpipe on the outboard side, (not interfering with the crankcase doors) leads oil through drillings in the A frames (red) to the main bearings where it goes through drillings in the crankshaft to the crankpin bearings, then down in the crankcase bottom and drains via the lowest point fore and aft to the external drainsystem. Hopefully you are able to trace the external supplypipe along the engine, unfortunately I don`t have any picture showing same.
Tore

Again a big thanks! I was wondering how this work :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 11:42
Luboil connections main engine

Tore, is the green arrow is...
And the orange arrow is the 'Thermometer' ???

http://www.uboatarchive.net/U-570Plate14.htm (http://www.uboatarchive.net/U-570Plate14.htm)

(http://img822.imageshack.us/img822/1366/new2zd.jpg)
Source: U-995 DVD http://www.uboataces.com/u995.shtml
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 11:55
Luboil connections main engine

Q2. On the plate 14 the 'Luboil connections main engine' line connect to the supercharger, this is incorrect?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 11:58
Simon.
The luboil pipes on fwrd engine is a challenge. I cannot remember every details and don`t have  many pictures so I have to make some guesses. Down below is my idea of the system, feel free to change it as I`m not 100% sure, but may be you are able to follow the pipes on other photos.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 12:19
Simon.
The valve indicated by you with green arrow is wrongly marked as "filter" on the U-historia photos so don`t get confused. As can be seen on my picture above I believe this migth be the pump relief ( safety) valve marked "h" on my colourmarked systemdrawing. The colours on the drawings should match the colourindication on the photo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 12:49
Simon.
Luboil connections main engine

Q2. On the plate 14 the 'Luboil connections main engine' line connect to the supercharger, this is incorrect?

Simon.
Contrary to the MAN turbocharger system, having a separate luboilsystem, the GW engine having a mechanical supercharger takes luboil from the enginesystem indicated on the sketch below . On the fwd end is a torsional vibrationdamper which needs luboil from the system as well,  might get it from main bearingsupply no 1 through drilling in the crankshaft. Drain from vibrationdamper yellow marked on systemdrawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 18:34
Simon.
Luboil connections main engine

Q2. On the plate 14 the 'Luboil connections main engine' line connect to the supercharger, this is incorrect?

Simon.
Contrary to the MAN turbocharger system, having a separate luboilsystem, the GW engine having a mechanical supercharger takes luboil from the enginesystem indicated on the sketch below . On the fwd end is a torsional vibrationdamper which needs luboil from the system as well,  might get it from main bearingsupply no 1 through drilling in the crankshaft. Drain from vibrationdamper yellow marked on systemdrawing below.
Tore


Have not idea how luboilsystem was contacted to the supercharger, so left this end of the pipe open for now.

(http://img850.imageshack.us/img850/4566/graphic1c.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Dec , 2012, 18:43
(http://img507.imageshack.us/img507/9620/new1hl.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 23:45
Simon.
It looks OK to me. When you fit the charging air receiver  below the exhaust receiver you probably don`t see much of it, but it is there.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Dec , 2012, 23:50
Simon.
Below is my indication of the luboil pipes on the Roots blower ( supercharger). The system contains a double cone frictionclutch as well which needs luboil.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Dec , 2012, 00:33
Roots blower.
Below is a sketch showing the working of the blower. On the end you have a geardrive accurately timed so the rotors don`t touch. This gearbox needs the luboil supply.
On the photo you see a modern version beltdriven. Even today they have the external oil supply pipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Dec , 2012, 07:04
Simon.
Secondary luboil system.
Next step is the secondary luboil system as indicated on the sketch below. From the luboilpump pressure side oil passes a discharge checkvalve "b" to the cooler. The cooler has a ventpipe with a valve " l" for venting, the pipe is connected to the drain ( yellow). After the cooler is a selector cock "c1" enabling a crossover connection to stb/port engine. Further before the pressure reductionvalve 3>1,5 kg/cm2 is a branch off to the governor servomotor for the fuelrack, the servo motor needs higher pressure than the enginelubrication, after the servomotor to drain as previously discussed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Dec , 2012, 08:01
Simon.
Emergency luboil system.
In case of a failure on the attached engine luboil pumps it is possible to use the fuel transferpump as emergency lub oilpump as indicated on the sketch below. Suctionpipes are coloured blue. Suction is taken separately either from port or stb systemtank via an OPZ valve ( 3position valve) in the tank as previously discussed. The centrifugal fuel transferpump,  deliver   red, to the valvechest and then to the engine pump pressureline. The checkvalve stops the entrance to the enginepump and the emergency pump delivers to the luboilcooler and then the standard system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Dec , 2012, 10:36
Simon.
It looks OK to me. When you fit the charging air receiver  below the exhaust receiver you probably don`t see much of it, but it is there.
Tore

Tore, you are right, you will not see must of the pipe, but it there ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Dec , 2012, 10:37
Roots blower.
Below is a sketch showing the working of the blower. On the end you have a geardrive accurately timed so the rotors don`t touch. This gearbox needs the luboil supply.
On the photo you see a modern version beltdriven. Even today they have the external oil supply pipes.
Tore

Thanks for this information! I have always wonder how this worked and looked :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Dec , 2012, 10:43
Simon.
Lub oil handpump system.
The final "layer" would be the hand pumpsystem. The hand pump at stb side towards the batteryswitch bulkhead takes suction from valve "k" at the valvechest and via the blue pipe and valve "g"  Pressure pipe , red, via cock "h" to the daily luboil consumption tank ( for filling handcarried oilcans) situated at the same bulkhead, further to the valve chest and into the cooler and engine luboil system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Dec , 2012, 21:05
Engine Lubricating Oil System continue to grow

Piping between the Engine lubricating oil manifold and the Auxiliary Lubricating Oil Pump

(http://imageshack.us/a/img585/4971/55508487.jpg)

(http://imageshack.us/a/img217/690/47817989.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jan , 2013, 07:19
Simon.
Your are coming along nicely with the luboilsystem. I am not sure about the smaller pipeline with a valve touching  the pressurehull bilge. See my markings below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jan , 2013, 11:12
What smaller pipe is a older version and will be update soon. I just need to workout what the valve look like first.

Also next to the Auxiliary Lubricating Oil Pump, are two lines named "FO Transfer Line", where do these go, I can not found where they go?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jan , 2013, 12:22
What smaller pipe is a older version and will be update soon. I just need to workout what the valve look like first.

Also next to the Auxiliary Lubricating Oil Pump, are two lines named "FO Transfer Line", where do these go, I can not found where they go?
Simon-
The pump is primarily a fueloil transfer pump, which is used as an emergency luboil pump . Below is the connections to the relevant valvechest. As you see it is even used for pumping fuel from shore to the fueloil bunkertanks.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jan , 2013, 13:35
Tore, this section of pipe is mark as 'high pressure' :o should it not be mark as 'low pressure'?

(http://img822.imageshack.us/img822/2251/new3yi.jpg)
http://www.uboatarchive.net/U-570Plate14.htm (http://www.uboatarchive.net/U-570Plate14.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jan , 2013, 13:55
Hi Tore

When you have time could you please check my pipes, thanks.
(http://img826.imageshack.us/img826/588/new5z.jpg)
(http://img267.imageshack.us/img267/1556/img1808xf.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jan , 2013, 14:44
Tore, this section of pipe is mark as 'high pressure' :o should it not be mark as 'low pressure'?

(http://img822.imageshack.us/img822/2251/new3yi.jpg)
http://www.uboatarchive.net/U-570Plate14.htm (http://www.uboatarchive.net/U-570Plate14.htm)
Simon
Absolutely!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2013, 07:59
Simon.
Valvechests.
May be an explanation of a valvechest makes a difficult system easier to understand. As seen below the valvechest has 5 chambers, two suction, drain    ( blue) and pressure, discharge (red) and three distribution chambers. There are two connections to the suctionchamber and two connections to the dischargechamber. By the use of 6 valves in the chest you are able to connect the various pipelines either to suction(drain) or pressure ( discharge) chambers.
Below I have tried to visualize how the system works leaving out the fuelsystem to simplify.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2013, 08:18
Simon.
The blue and yellow colours were not very readable so I have overwritten the text below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2013, 11:13
Simon.
I believe the valvechest for filling the luboil storage tanks is placed just underneath the main luboil valvechest as shown on the photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jan , 2013, 11:36
Simon.
Valvechests.
May be an explanation of a valvechest makes a difficult system easier to understand. As seen below the valvechest has 5 chambers, two suction, drain    ( blue) and pressure, discharge (red) and three distribution chambers. There are two connections to the suctionchamber and two connections to the dischargechamber. By the use of 6 valves in the chest you are able to connect the various pipelines either to suction(drain) or pressure ( discharge) chambers.
Below I have tried to visualize how the system works leaving out the fuelsystem to simplify.
Tore

Thanks Tore!

Very useful, will start updating my drawing this morning.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jan , 2013, 11:37
Simon.
I believe the valvechest for filling the luboil storage tanks is placed just underneath the main luboil valvechest as shown on the photo below.
Tore

Great found! I been looking for this :) :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jan , 2013, 14:58
Engine Lubricating Oil System continue to grow

Piping between the Engine lubricating oil manifold and the Lubricating Oil Hand Pump. I was not able to workout the original German pipe layout for this section :(, so this is my best estimation. I am sure this will change over time as I keep adding more piping, valves etc...

(http://imageshack.us/a/img32/4355/new1og.jpg)

(http://imageshack.us/a/img818/2364/new3t.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 00:16
Simon.
So far so good, I`ll see if I can figure out more details on the pipe. I am not sure about the valve/ pipebranch for the fwd bilge, drain/floodconnection, I thought it was more forward, port side of the galley/engineroom door.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Jan , 2013, 00:43
Simon.
So far so good, I`ll see if I can figure out more details on the pipe. I am not sure about the valve/ pipebranch for the fwd bilge, drain/floodconnection, I thought it was more forward, port side of the galley/engineroom door.
Tore

Tore, this is a very good question about valve/pipe branch for the fwd bilge. I have never like this section of pipe but I thought I was following the plans. However, I just rechecked them and now I can not found it now on the plan. I will look into this in detail in the morning.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 02:05
Simon.
Sometime the landscape doesn`t fit the map. My handpump theory is the hoseconnection for hand pumpsuction is placed near the main valvechest as can be seen on the photo below. The rest of the system is pretty obvious as can be seen on the other pictures, the blue colour had to be change into purple as it disappeared in the bad qualityphoto. Note the tiny details with the luboil consumption tank, it was topped up by the handpump and used for filling the handcarried oilcans (rockerarms lubrication) that`s why the two tiny cocks and the driptray underneath the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 04:38
Simon.
Checking my morning post I see the 3rd photo of the luboil pumpsystem somehow did not turned up in the attached pictures :( , so down below it is. ;)
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 05:55
Off the topics.
Today the Royal Norwegian Navy is conducting a new investigation of the famous U-864, a IXC which was sunk by the Royal Navy's submarine HMS Venturer February 1945 on her maiden voyage 2-3 nautical miles off the Norwegian westcoast. All hands, 73 men lost . On the net are extensive details of a fascinating hunt for the U864. U-864 was on a secret mission " Cesare" transporting Messesmitt jet engineparts to Japan as well as 65 tonnes of mercury and the wreck was discovered by the Royal Norwegian Navy October 2003. She is laying in two parts at approximately 150 meters depth. Even today a German WW2 submarine is creating difficulties, as corrosion increase the risk of mercury leaking into the sea, up to this date 13 million US dollars has been spent to figure out what to do with the mercury leakage. Even with the sophisticated equipment we have from the offshore oil drilling it is a complicated and expensive task to raise it. Not to speak of the the fact it is a war grave. The fishing in the area is prohibited and a tug of war is going on between the local people and the authorities what to do with the mercury. May be the renewed investigation shall find a solution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 03 Jan , 2013, 07:07
Tore, times ago i came across a report about U-864 in the news on some italian TV channel and was wondering what was the present state of the mercury monitoring like. Obviously, once given the new months ago, no italian TV cared about updating people on the subject anymore. At the time the readings of mercury concentration in the wather were reported as normal, thus not posing a real threat to sea species. How's the story developing?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jan , 2013, 07:21
Hi Tore,


I have got another off-topic question. The schnorchel mast on KNM Kaura was elevated by means of hydraulic power taken from the installation for periscopes hoists. I wonder, if there was any emergency procedures, in case of damaging hydraulic installation (the periscopes could be raised and lowered by hand). When almost all systems were backed-up, it would be strange to be not able operate schorchel without hydraulic power. Maybe there was some kind of hand pump to build the pressure in installation?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 08:08
Tore, times ago i came across a report about U-864 in the news on some italian TV channel and was wondering what was the present state of the mercury monitoring like. Obviously, once given the new months ago, no italian TV cared about updating people on the subject anymore. At the time the readings of mercury concentration in the wather were reported as normal, thus not posing a real threat to sea species. How's the story developing?

SG
Since 2004 annual monitoring of mercury content both in the fishes,seaweeds and sediments is carried out. So far no dangerous levels has been found. The trouble is they have not been able to check or monitor the state of corrosion on the steelcontainers where the mercury is stored. Right now they are having a new attempt to establish the condition. In the meantime fishing and eating seafood from the area is prohibited. This is of course a highly unsatisfactory situation for the local people. The main concern today is the fuel leakage which probably shall happen before a possible mercury leakage.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 08:15
Maciek.
I have tried to remember a possible handoperation of the snortmast, but cannot remember any such thing. A possible hand rising of the mast would require considerable power. I don`t believe we had an alternative risingdevice.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Jan , 2013, 11:01
Off the topics.
Today the Royal Norwegian Navy is conducting a new investigation of the famous U-864, a IXC which was sunk by the Royal Navy's submarine HMS Venturer February 1945 on her maiden voyage 2-3 nautical miles off the Norwegian westcoast. All hands, 73 men lost . On the net are extensive details of a fascinating hunt for the U864. U-864 was on a secret mission " Cesare" transporting Messesmitt jet engineparts to Japan as well as 65 tonnes of mercury and the wreck was discovered by the Royal Norwegian Navy October 2003. She is laying in two parts at approximately 150 meters depth. Even today a German WW2 submarine is creating difficulties, as corrosion increase the risk of mercury leaking into the sea, up to this date 13 million US dollars has been spent to figure out what to do with the mercury leakage. Even with the sophisticated equipment we have from the offshore oil drilling it is a complicated and expensive task to raise it. Not to speak of the the fact it is a war grave. The fishing in the area is prohibited and a tug of war is going on between the local people and the authorities what to do with the mercury. May be the renewed investigation shall find a solution.
Tore

I have download and read several of the reports on U-864 and they are very detail. I can see where some of the 13 million dollars went.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Jan , 2013, 11:14
Simon.
Checking my morning post I see the 3rd photo of the luboil pumpsystem somehow did not turned up in the attached pictures :( , so down below it is. ;)
Tore

Thanks Tore for the picture :) :) I been looking for the LO consumption Tank.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Jan , 2013, 11:22
Simon.
Sometime the landscape doesn`t fit the map. My handpump theory is the hoseconnection for hand pumpsuction is placed near the main valvechest as can be seen on the photo below. The rest of the system is pretty obvious as can be seen on the other pictures, the blue colour had to be change into purple as it disappeared in the bad qualityphoto. Note the tiny details with the luboil consumption tank, it was topped up by the handpump and used for filling the handcarried oilcans (rockerarms lubrication) that`s why the two tiny cocks and the driptray underneath the tank.
Tore

A nice found on the hand pump suction house connection.
 
Yesterday while I was updating my drawing I could not found this house connection on the starboard side on the boat but found one on the port side. I was not sure if this was the hand pump suction house connection.
 
I will update my drawing tomorrow, as I am off to a friend wedding today.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2013, 23:58
Off topics
U 864 type IXD2.
For those who might be interested. The Norwegian authorities has estimated the cost of rising the submarine to be approximately 1.5 billion NOK equivalent to US
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Jan , 2013, 01:52
Off topics
U 864 type IXD2.
For those who might be interested. The Norwegian authorities has estimated the cost of rising the submarine to be approximately 1.5 billion NOK equivalent to US
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jan , 2013, 04:39
I guess you have a point Simon. However I believe this is the way they are doing it with nuclear disasters like Tschernobyl. the North Sea is like a Swiss cheese with many empty dry oilwells, why not utilise those wells. One of the tasks for the present investigation is to evaluate the condition of the mercuryflasks if they are at all movable. An interesting submarine detail is the way these 65 tonnes of mercury steelflasks are stored on board the U 864, they are stored in the box keel, I never realised they used the keel as cargohold. I bet the boat was pretty stiff at sea with 65 tonnes in the keel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jan , 2013, 06:23
Simon .
Luboil handpump.
A small correction to the luboil handpump system. The cock at the pumpoutlet is not the supplypipe, but a ventcock ( green colour). The supply
 ( pressure)pipe goes behind the pumps,dotted red, and have a branch off to the tank not visible behind the coolingwater handpump and to the top of the luboil consumptiontank having a smallvalve on the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Jan , 2013, 11:16
I guess you have a point Simon. However I believe this is the way they are doing it with nuclear disasters like Tschernobyl. the North Sea is like a Swiss cheese with many empty dry oilwells, why not utilise those wells. One of the tasks for the present investigation is to evaluate the condition of the mercuryflasks if they are at all movable. An interesting submarine detail is the way these 65 tonnes of mercury steelflasks are stored on board the U 864, they are stored in the box keel, I never realised they used the keel as cargohold. I bet the boat was pretty stiff at sea with 65 tonnes in the keel.
Tore

I think it was in "U-Boat Far From Home" by David Stevens, that I read that near the end of the war it was common for Type IX's to come home to German from Japan and German ports in Malaya and East Indies with there cargohold full of rubber or tin.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jan , 2013, 11:46
Simon .
My last post on the luboil handpump was mutilated, I have corrected same just now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Jan , 2013, 18:11
Engine Lubricating Oil System
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jan , 2013, 01:26
Simon
You are only at the starting point to fill the spaghetti bowl :D . An important pipe is the pipe through the pressurehull used for filling (bunkering) new luboil and to deliver (discharge) old. The pipe connects to the center of the valvechest, even that one between the chest and the bulkhead. The two centervalves connects the pipe respectively to the pressure and suction side of the pump. The pipe with coarsefilter and boardvalve is very visible on the port side of the engineroom-galleydoor going to the top of the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jan , 2013, 02:02
Simon.
It is quite a puzzle to accommodate all the pipes and valves but may be you should try to  distinguish the handpump hoseconnection with valve from the main valvechest as it is not a part of same. The handwheel of the hoseconnection valve is not in place on U 995, but the valvehouse is visible.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Jan , 2013, 14:18
Here the new alignment and new valve of the drainage system.
http://www.uboatarchive.net/U-570Plate6.htm (http://www.uboatarchive.net/U-570Plate6.htm)

(http://imageshack.us/a/img832/9117/pp2eb.jpg)

(http://imageshack.us/a/img11/2044/pp1zj.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jan , 2013, 14:23
Simon.
Drainagesysystem.
Much better!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Jan , 2013, 15:30
I found it hard to believe the Germans design a U-boat without CAD. I am amazes how they would leave enough room for the next pipe. Two great example of this are the valves for the Cooling-water system (you can see how Engine Lubricating Oil pipes arc and bend around the valves) and the other is leaving room for the forward drainage valve.

(http://img248.imageshack.us/img248/4728/new1y.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Jan , 2013, 15:34
Heard somewhere that there were 40,000 set of drawings for the Type XXI :o :o
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jan , 2013, 15:39
Simon.
I guess now you have an idea why the left out the valvewheels and have rod extensions to the floorplates.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jan , 2013, 15:42
Heard somewhere that there were 40,000 set of drawings for the Type XXI :o :o
It could very well be, but I believe complicated pipe models were used as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Jan , 2013, 16:26
Heard somewhere that there were 40,000 set of drawings for the Type XXI :o :o
It could very well be, but I believe complicated pipe models were used as well.
Tore

In The U-Boat: The Evolution and Technical History of German Submarines by Eberhard Rossler, were are several pictures of wood models of new bridge conversion.

The US Virginia class was the first US sub to be totally design by CAD, all previous US sub
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jan , 2013, 00:15
I remember in the shipyards drawing offices there were fairly large models of pipeline layouts where the various pipes had different colours. A lot of work and materials could be saved by optimising the the design. I was involved in supplying large dieselengines to the shipyards and we made a proposal of the pipings the way we wanted to have the lay out and the yards designed the systems according to their needs within the requirement of the enginebuilder and sent it to the enginebuilder for approval. It would be nice to have such a pipeline model of the VIICs rigth now :D !
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jan , 2013, 11:51
Hi Tore

I have run into a problem with the drain valve.

I place the valve at the drain pipe level and run a linkage to the handle that we can see in the Galley. However, to reach the handle in the engine room, its about 1300 mm below the deck and too far to be reach by hand :(

Do you think they place the engine room valve handle higher up the linkage?

(http://img607.imageshack.us/img607/4379/new1u.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jan , 2013, 14:06
Simon.
I don`t think so. The main purpose of having  an opening handle in an adjacent room (galley) is to be able to open the engineroom drain valve  from the galley in case the engine room was flooded. Under normal circumstances you could easily open the engineroom bilgevalve by the galleyhandle some 20 cm away. I believe we mostly used the aft bilge drain valve.Thus in spite of the systemsketch I believe this valve was only opened from the galley.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jan , 2013, 15:15
Simon.
I don`t think so. The main purpose of having  an opening handle in an adjacent room (galley) is to be able to open the engineroom drain valve in from the galley in case the engine room was flooded. Under normal circumstances you could easily open the engineroom bilgevalve by the galleyhandle some 20 cm away. I believe we mostly used the aft bilge drain valve.Thus in spite of the systemsketch I believe this valve was only opened from the galley.
Tore

Thanks, Tore.


(http://img694.imageshack.us/img694/2500/new1op.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jan , 2013, 23:29
Simon.
I like it. A very small detail. Top cover of the coarsefilter for the luboil filling line has a transom with a tophandle. You see a good photo of this detail on u historia engineroom section.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jan , 2013, 23:54
Simon.
I like it. A very small detail. Top cover of the coursefilter for the luboil filling line has a transom with a tophandle. You see a good photo of this detail on u historia engineroom section.
Tore

Thanks Tore :) :) I had no good photo's of the course filter, so I will add the top handle tomorrow.

I have not be able to locate the main LO Manifold (Valve 'a' & 'a1') but I imagine its between the two coolers & centre line of the boat, Tore can you remember?
http://www.uboatarchive.net/U-570Plate14.htm (http://www.uboatarchive.net/U-570Plate14.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2013, 01:12
Simon.
Valves a1 and a2.
I guess you are right, between the cooler. I should think these valves got an extension to the floorplates as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2013, 01:42
Coarsefilters.
Just a word on the coarsefilters. These rough filters designed to give minimum of resistance, are often installed in supplypipes which takes deliveries from outside the boat in order to protect transferpumps etc from " nuts and bolts" entering the system. Sometimes we got impurities particulary when fueling which really were nuts and bolts, so it was highly justfied to have these filters.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dbauer on 07 Jan , 2013, 07:48
 ;D  Hey!
Are you going to do the plumbing for the Head too?!!? Or have you already done that? LOL....
Regards,
Dan
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2013, 08:28
Hi Dan!
The plumbing of the heads is very simple although not so easy to understand sometimes for some visitors.  We had a few blowback incidents with ladies during coctailparties on board in spite of giving detailed explanations of the plumbing ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dbauer on 07 Jan , 2013, 12:16
 ;D  Hi!
As they alawys told me" If all else fails, follow the instructions!" :-[
Regards,
Dan
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Jan , 2013, 12:55
Tore, just double checking, the LO gear pump is attach to the front of the engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2013, 13:12
Simon.
Yes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Jan , 2013, 13:20
Sad news Tore. I think I gone as far as I can on the original German pipe layout and arrangement with the information & drawing I have. From this point forward all new piping I add to the engine room will be best educated guess.
 
For me to get any more accurate layout and arrangement we need either a few days within U-995 (with the floor remove) or original German plans.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2013, 14:21
Simon.
I guess we a have a few more items we can elaborate, starting with the aux. luboilpump and its 2nd task, fueloil transport. If you look at the system below you are able to trace the red encircled valvechest and the fuel filling line with the coarsefilter. If you look towards the galleydoor stb side, you find the fuel filling line with the fairly large black valve wheel disappearing towards the floorplates, just like the luboil filling line on the port side of the door, howewer the coarse filter is missing. Then you go to u historia engineroom page and one of the last pictures there you`ll find the coarsefilter (clearly showing the design) and the valvechest A underneath the heatexchanger, (circular large tube), from this valvechest it is possible to follow the suction and dichargepipe up to the pressure hullside and across to portside and the pump. This is quite a deviation from the pipesketch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 01:33
I can not believe it! After spending all day looking at the Lubricating Oil System, I was working out one more original German pipe layout and arrangement  :) :) :) :) :)

(http://img854.imageshack.us/img854/1341/new1hu.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 02:10
Simon.
Look good and easy to understand :D . As so many times before there are  extra details which belongs to even a simple system. When you start to draw the enginedriven pumps discharge outlet you have the branch off to the reliefvalves which I believe you shall find way out to the port and starboard side. See your own picture below.
Another detail on the suction pipe is the weedblow connection on the seaboard valve and, as you love to go into tiny details, the small ball on the seaboard valve.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 06:05
Simon.
Maciek provided a crossection drawing of the engine driven coolingwater pump some time ago. Below I have tried to illustrate the working of same. It looks as the pump has one common suction inlet and the branch off to the two pumpcylinders is intergrated in the pump (blue) the discharge( red) is howewer two flangeconnection on each side of the pump. The comparatively large red chamber is even extended by the bulb (damper) to dampen the pulsation of the waterpressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 08:11
Simon.
In my yesterdays post on fuel fillingsystem I went a bit far drawing the conclusion of having discovered the fuel chest :-\ . The fuelfilling pipe, valves and the coarsefilter are OK, but connecting it up to the chest under the heatexchanger is a bit far fetched, I guess we have to go to the port side. I believe now the chest is the main cooling waterchest which is relevant to your last drawing of the coolingwater suctionpipe and pumps. The handles of the valvechest are without doubt seawater valvehandles and I cannot find any fuelmeter. Thus the fuelchest is still missing and probably hidden underneath the floorplates :( .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 11:15
Simon.
Look good and easy to understand :D . As so many times before there are  extra details which belongs to even a simple system. When you start to draw the enginedriven pumps discharge outlet you have the branch off to the reliefvalves which I believe you shall find way out to the port and starboard side. See your own picture below.
Another detail on the suction pipe is the weedblow connection on the seaboard valve and, as you love to go into tiny details, the small ball on the seaboard valve.
Tore

Relief valves
This is great! I have always wonder that this was :) :)

Weed blow
I have started to add this layer but yet to finish it ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 11:24
Simon.
Maciek provided a crossection drawing of the engine driven coolingwater pump some time ago. Below I have tried to illustrate the working of same. It looks as the pump has one common suction inlet and the branch off to the two pumpcylinders is intergrated in the pump (blue) the discharge( red) is howewer two flangeconnection on each side of the pump. The comparatively large red chamber is even extended by the bulb (damper) to dampen the pulsation of the waterpressure.
Tore

Tore, thanks for confirming the location of the cooling water discharge. I was virtually sure this was the outlet but was not 100% sure.

Yesterday while looking at the Lubricating Oil system I search the net about the duplex piston pumps, very interesting.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 11:37
Simon.
In my yesterdays post on fuel fillingsystem I went a bit far drawing the conclusion of having discovered the fuel chest :-\ . The fuelfilling pipe, valves and the coarsefilter are OK, but connecting it up to the chest under the heatexchanger is a bit far fetched, I guess we have to go to the port side. I believe now the chest is the main cooling waterchest which is relevant to your last drawing of the coolingwater suctionpipe and pumps. The handles of the valvechest are without doubt seawater valvehandles and I cannot find any fuelmeter. Thus the fuelchest is still missing and probably hidden underneath the floorplates :( .
Tore

I have located fuel chest manifield, it under the step into the engine room from the Galley. The Germans even cut a hand hold in the face of the step for access.

Q. Tore, I was wondering were the floor plating
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 12:07
Very good Simon!
As far as I remember the floorplates were fixed by countersinked screws, I am no100 % sure. Anyhow the plates were fixed, imagine the rattling produced by loose plates.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 12:18
Simon.
Looking at your above photo I wonder if the two guys are "tanning"under an ultraviolet lamp. We had such a lamp left behind by the Germans and I used it a few times. It was a monster making spark noises and smelled ozone. It did probably more harm than good.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 12:56
Q. Tore, the large funnel under the relief valves, would it just run into the bilge?

Post number 1000  8) 8) 8) 8) 8) 8) 8) 8)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 13:24
Quite a different topic - I have just noticed, that in the aft part of the control room, where should be located the hand wheels for the head valves of the diesel engine air induction trunk, ventilation air intake and exhaust, one of these valves - ventilation air intake is missing:
(http://img19.imageshack.us/img19/6198/ventilationhullvalvesco.jpg)
http://www.kubische-panoramen.de/index.php?id_id=5378&p=i (http://www.kubische-panoramen.de/index.php?id_id=5378&p=i)


It looks like after installing Schnorchel, the intake of the ventilation trunk was blanked. Moreover, the foot valve closing this trunk in the diesel engine room is still in place. I suppose, it was left to allow drain the trunk after accidental flooding.
Generally, such arrangements is like ventilation system on the "Schnorchel boats" - U-Boats type XXI and XXIII.




--
Regards
Maciek

Maciek, great found! I also noted this last week when I was updating my Schnorchel drawing and was wondering what it was. I was going to ask you what it was ;D

Hi Maciek

I not know why I forget this. Several years back I noted this and email Dani at u-historia.com. It was confirm that there is a connection between both control wheels. Updated drawings at found at
http://www.u-historia.com/uhistoria/tecnico/visitaguiada/ventilaciones/ventilaciones.htm (http://www.u-historia.com/uhistoria/tecnico/visitaguiada/ventilaciones/ventilaciones.htm)
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 13:32
Simon.
Coolingwater reliefvalves.
As the valve dispose only clean seawater I believe it goes into the bilge. Howewer the drain goes into a funnel at floor platelevel so when, and if it is open you can check and prevent water flushing the floorplates .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 13:38
Q. Tore, the large funnel under the relief valves, would it just run into the bilge?

Post number 1000  8) 8) 8) 8) 8) 8) 8) 8)
Yes Simon its becoming quite a mailbox! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 13:47
Q. Tore, I am confused about the line between the CW pump and the valve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 14:01
Q. Just checking that this is this section of piping.

(http://img255.imageshack.us/img255/8285/new1rg.jpg)
(http://img593.imageshack.us/img593/9634/new5q.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 14:19
Simon.
Sometimes when starting a cold engine, you want to heat it up as quickly as possible, instead of pumping calories overboard you put the calories (warm water) back to the suction side of the coolingwater. In case of a freshwatercooling like on USN submarines you would bypass the freshwatercooler but these engines have no cooling watercooler hence returning the warm seawater.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 14:38
Simon.
I am a bit bewildered, the photo you are showing is the port engineattached luboilpump with reliefvalve. The purple T could very well be the thermometer pocket for the coolingwater inletpipe to the port engine corresponding to the purple bend on the stb engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2013, 22:40
Tore, today while researching the Lubricating Oil System I was able to workout a large part of the Cooling-water system, this includes working out the original German pipe layout and arrangement :) :) :) I will almost totally redraw the Cooling-water system and this will take me a few days. I will post updates soon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2013, 23:57
Simon
Looking forward to seeing it!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jan , 2013, 02:34
Hi Simon


I not know why I forget this. Several years back I noted this and email Dani at u-historia.com. It was confirm that there is a connection between both control wheels. Updated drawings at found at
http://www.u-historia.com/uhistoria/tecnico/visitaguiada/ventilaciones/ventilaciones.htm (http://www.u-historia.com/uhistoria/tecnico/visitaguiada/ventilaciones/ventilaciones.htm)


Interesting note. Thanks for information.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dbauer on 09 Jan , 2013, 11:02
 ;)  Very nice model! You did alot of modifying and that is great! Well done! A model is your own idea of how you want it to be!  Don't let anyone tell you otherwise!
Regards,
Dan
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 12:05
I can not believe it! After spending all day looking at the Lubricating Oil System, I was working out one more original German pipe layout and arrangement  :) :) :) :) :)

(http://img854.imageshack.us/img854/1341/new1hu.jpg)

Tore, as we know that were two inlets to the CW pumps, would there be two outlets?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2013, 12:36
Simon
I`m not sure there are two inlets see sketch below, I believe there are two discharge outlets port and starboard ( red arrows).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2013, 12:52
Simon
If you look at the topview engineroom arrangement you`ll find two flanged connection on the forward front of the engine on each side of the centerline of the engine, I guess that is the discharge. Towards engine room centerline (inboards) I guess you `ll see the suction inlet very low down.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 13:22
Tore, from what I can workout from the Shipyard Drawings it does not seen to match the Design and Specification Books drawing.

From that I can work out there no linkage between the pump and valve 'f',but like the drawing I have added, could this be right or have I got this all worng?

(http://img339.imageshack.us/img339/9659/new3fp.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2013, 13:34
Dan
The model of KNM Kaura ex U 995 is as you remark deviating quite a bit from the conventional model kit of a VIIC. It shows one of three modified VII Cs serving in the R.Nor. Navy as from early 50s till mid 60s. The philosophy at that time was a submarine should stay submerged by means of snort most of the time, rather than take up fight with surface and air enemies. That`s why we did away with all the guns and wintergarden keeping a minimum of tower. Later we converted one of the VII Cs with a modern "sail" as well.
I rather concentrated on technical details than the weathering, brownwash and canning. The model shows the norwegian tower, details of the opened Kingstons, the difference between the saddletanks and main ballasttank no 3 kingstons, fitting the snortmast bend above the casingdeck starboard, which is missing on most snortmast models, reducing the deckcontainers, did away with the"deck winglets" located in the wintergarden area, change some of the floodgates, moved the anchor forward, change the antennas wireintake, sternlantern and a few smaller items. The major deviation details can be seen from the photo below
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 13:41
Tore, I am starting to get a little lost with this layout. To help me have I mark the correct layout below?

(http://img706.imageshack.us/img706/9783/new5t.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2013, 14:01
Simon.
I guess you can find the exhaust coolingwater outlet on the drawing by following the pipe on the photo. The pipe goes a bit aft then down almost around the exhaustmanifold and then forward to the suction line.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2013, 14:37
Simon
Below is a sketch I made in a hurry late night my time. The blue is the suction lines, the red is the pressure lines. The red pressurelines get a reduced pressure decreasing by the distance from the pumps. The warm return coolingwater outlet from the exhaustmanifold has to be boosted by the cooling waterpump either by the enginedriven pump or the electric circulatingpump. So the return of warm water has a bit higher pressure than ordinary suction, howewer you  usually don't use all the water. You are throttling the pressure by the suctionvalve as you mix the warm water with cold seawater in order to prevent overheating. Sounds complicated? ??? it is quite normal. Today you would have a thermostat. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 15:21
Thanks Tore. Its helping. Now only 1/2 lose :D :D

I have found all the pipes but this section in red, could it be internal part of the pump/engine?

(http://img560.imageshack.us/img560/397/new2ao.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 15:28
I will draw up a colour map of my piping layout today so you can double check my layout tomorrow.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2013, 15:52
Here is my layout and the missing pipe I can not find :( :(

From that I can see from the drawing there are two inlets and two outlet for the CW pump ???

(http://img819.imageshack.us/img819/1760/new5zk.jpg)
(http://img35.imageshack.us/img35/2461/new6sm.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 01:21
Thanks Tore. Its helping. Now only 1/2 lose :D :D

I have found all the pipes but this section in red, could it be internal part of the pump/engine?

(http://img560.imageshack.us/img560/397/new2ao.jpg)

Simon
Part of the section could of course be intergrated in th pumps suction side, howewer we should be able to trace the valve. I`m still of the opinion that the pipe  on the previous shown exhaust manifold photo is leading down between the manifold and pressurehull and entering the suctionpipe via a valve the  somewhere down. The valve should be able to control from the floorplate hight. I`ll keep looking while it is your turn to go sleeping. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 01:48
Here is my layout and the missing pipe I can not find :( :(

From that I can see from the drawing there are two inlets and two outlet for the CW pump ???

(http://img819.imageshack.us/img819/1760/new5zk.jpg)
(http://img35.imageshack.us/img35/2461/new6sm.jpg)
Simon seems to be OK.  The valve "f" is a two way valve, either shut to the cooler or to the engine supply pipe. The pipe out from the cooler has an ordinary shut off valve both are fairly close and fitted at the top of the cooler.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 08:04
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifoldup to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive coolingwaterpump via a valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 08:31
Simon additional photos to my last post.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 11:27
Thanks Tore. Its helping. Now only 1/2 lose :D :D

I have found all the pipes but this section in red, could it be internal part of the pump/engine?

(http://img560.imageshack.us/img560/397/new2ao.jpg)

Simon
Part of the section could of course be intergrated in th pumps suction side, howewer we should be able to trace the valve. I`m still of the opinion that the pipe  on the previous shown exhaust manifold photo is leading down between the manifold and pressurehull and entering the suctionpipe via a valve the  somewhere down. The valve should be able to control from the floorplate hight. I`ll keep looking while it is your turn to go sleeping. :)
Tore

Tore, were you able to find valve 'f'?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 11:52
Simon.
I have not found any valve on that part of the pipeline.May be it is intergrated in the pumpcasing, but anyhow we should be able to see the wheel handle. I`m still looking.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 12:21
Tore, this morning I was able to track/trace the outlets for the CW pump. The shape and the layout of the pipe suggest two outlets and two inlets for this pump.

(http://img339.imageshack.us/img339/290/new1xl.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 12:33
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifoldup to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive coolingwaterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 12:57
Simon
Colingwater outlets.
 The outlets looks fine to me :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 13:03
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.

Simon
Heathexchanger.
I believe it is the original. It is really a straight forward oldfashioned tube heatexchanger  not the modern plate exchanger used today.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 13:53
Very good Simon!
As far as I remember the floorplates were fixed by countersinked screws, I am no100 % sure. Anyhow the plates were fixed, imagine the rattling produced by loose plates.
Tore

"countersinked screws" would match the style the Germans used to fixed the metal cover on the deck. I can imagine the rattling produced by loose plates :D plus the noise of the plates jumping around while a depth charging would not be good ;)

Also this morning I was able to work out the width of the floor in the forward part engine room from original German drawing :) :) Tore can you remember roughly how big a single floor plate was. Were they all the same size or different sizes? I imagine they were small enough for a single person to remove them or did it take two people to remove them?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 14:05
Simon
Floorplates.
I really can`t remember excactly, howewer I believe they were of different sizes but could be handled by one man.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 14:11
Simon
Floorplates.
I really can`t remember excactly, howewer I believe they were of different sizes but could be handled by one man.
Tore

This is what I was thinking :) This would make the must sense. I will workout the sizes of the plates base on that valves below them.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Jan , 2013, 16:46
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.
Simon.
One leap ahead. ;D  On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.

Simon
Heathexchanger.
I believe it is the original. It is really a straight forward oldfashioned tube heatexchanger  not the modern plate exchanger used today.
Tore

Tore, I started relooking at the heat exchanger, and something does not add up. I believe the heat exchanger is original but it not in its original location.
 
If we look at a few things:

(http://img594.imageshack.us/img594/4372/new2zbb.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2013, 23:41
Simon.
You are touching upon something which for long has been in the back of my mind.
1.  I cannot remember this arrangement. Well that doesn`t mean too much.
2.  If you remember in June we had a discussion, Maciek, Christopher, you and me about the purifier and the horizontal port small circulatingpump not shown on any 
     pipescheme we couldn't`t figure out  what was the use of the pump.
3.  I launched the idea it was installed later even after my time.
If you add that up to your new ideas and include that this pump is indeed connected to the strange crossover to the starboard heatexchanger I believe we are on a track worth while to follow.
I`ll check further details today on that theory.
Tore
           
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 Jan , 2013, 07:36
Hi Gents


U 864 type IXD2.

For those who might be interested. The Norwegian authorities has estimated the cost of rising the submarine to be approximately 1.5 billion NOK equivalent to US
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jan , 2013, 10:47
Maciek.
U 864 final days is a fascinating story illustrating the last hard times of the german submarine service at the end of WW2. Books are written on the subject.
She left Kiel just after  having schnorkel installed, ran aground in Norway, was bombed in the submarine pen in Bergen while repairing and was training the crew on schnorkeling just along the south western coast of Norway prior to departure for Japan. During those trials one of her engine started to misfire and they decided to return to Bergen for repairs. At that moment the hydrophone operator of HMS Venturer, which had been despatched for a hunt on U 864, heard some funny engine noises which he mistook for a semidiesel of a fishingvessel. U 864 apparently navigated too long by the periscope and was spotted by HMS Venturer. U 864 realizing they were spotted started to zigzag. HMS Venturer decided to fire her 4 torpedoes programming it for a 3 D pattern fairly unproven. U 864 heard the torpedoes were launched stop schnorkeling and went deep, avoiding 3 of the torpedoes, howewer the 4th had a hit  and U 864 imploded. It is claimed to be the first sinking of a submerged submarine by another submerged submarine ever. There are better and more accurate reports on the net, this only a brief incomplete story based on my memory.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jan , 2013, 12:12
Simon.
I am almost convinced the heatexchanger and port circulationpump is a modification possibly made after my time. I guess the handle of the water handpump was a modification which was necessary as the wooden handle came in conflict with the vertical copperpipe. We still haven`t localized the luboil purifier which is supposed to be hooked up to the heatexchanger. It is all very odd. I`m busy with the details of the coolingwater/ luboil system under the floorplates and shall possibly need a couple of days before I have some details on the subject.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Jan , 2013, 12:43
Simon.
I am almost convinced the heatexchanger and port circulationpump is a modification possibly made after my time. I guess the handle of the water handpump was a modification which was necessary as the wooden handle came in conflict with the vertical copperpipe. We still haven`t localized the luboil purifier which is supposed to be hooked up to the heatexchanger. It all very odd. I`m busy with the details of the coolingwater/ luboil system under the floorplates and shall possibly need a couple of days before I have some details on the subject.
Tore

Yes, very odd!!!

I am working on the exhaust cooling water outlet this morning trying to track it as far as possible.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Jan , 2013, 15:48
Tore, what does this handle open?

(http://img51.imageshack.us/img51/2992/new1wz.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Jan , 2013, 18:28
Tore, good news :) :) This morning I was able workout one more original arrangement for the Cooling Water System. I was able to add the line between the diesel engine and LO Cooler. I am yet to locate the pressure gage or thermometer.

I have also added the Relief valves, the lines to the Relief valve and funnels. Did you noted that the Relief valves at not in the same locates on the port and starboard side.

(http://img688.imageshack.us/img688/4852/new2nz.jpg)
Fig. 1. Cooling Water System.

(http://img72.imageshack.us/img72/6039/new3d.jpg)
Fig. 2. I love pipes  ;D ;D ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 Jan , 2013, 22:44
Hi Simon


Tore, what does this handle open?

(http://img51.imageshack.us/img51/2992/new1wz.jpg)


It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2013, 01:18




Tore, what does this handle open?

(http://img51.imageshack.us/img51/2992/new1wz.jpg)


It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek

Simon.
I guess you found the handle for the shut off valve of the return cooling water from the starboard exhaustmanifold. :D   Maciek is of course right the handle has a fuelvalve shape, but there are no fuel oilpipes in this area and as we have seen before handles have been mixed. The excellent photo of Maciek shows a valve and a pipe located where the coolingwater return bend should be. As far as I can see, you`ll not find this extension on the port side, you find a similar valve at the end of the pipe leading to the strange port circulationpump . I guess this support of theory that the circulation system has been cut in the original system and installed later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 Jan , 2013, 09:06
Tore,


U 864 final days is a fascinating story illustrating the last hard times of the german submarine service at the end of WW2. Books are written on the subject.
[...]
U 864 apparently navigated too long by the periscope and was spotted by HMS Venturer. U 864 realizing they were spotted started to zigzag. HMS Venturer decided to fire her 4 torpedoes programming it for a 3 D pattern fairly unproven. U 864 heard the torpedoes were launched stop schnorkeling and went deep, avoiding 3 of the torpedoes, howewer the 4th had a hit  and U 864 imploded.


Well, there are a lot of books written based on post-action reports. But these are taken without any criticism. For example, almost everyone say, that U864 was spotted becuase of exposed periscope (at distance 3200 yds = 2900 m !). Most likely, first was spotted snorkel head. There is also said, that commander of U864 realized, that he is followed by enemy and started to make these slight zig-zags (about 10 deg at each side) - would the commander take such action instead of switching electric motors and going below periscope depth? I would rather say, U864 was going with zig-zag course, and that the zig-zag pattern was recognized after some time of plotting. I also doubt about evasive maneuver - I don't think that hydrophone operator was able to hear incoming torpedoes while snorkeling.
Interestind discussion can be found here:
http://www.rnsubs.co.uk/Community/Forum/index.php/topic,3564.0.html


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Jan , 2013, 11:00




Tore, what does this handle open?

(http://img51.imageshack.us/img51/2992/new1wz.jpg)


It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek

Simon.
I guess you found the handle for the shut off valve of the return cooling water from the starboard exhaustmanifold. :D   Maciek is of course right the handle has a fuelvalve shape, but there are no fuel oilpipes in this area and as we have seen before handles have been mixed. The excellent photo of Maciek shows a valve and a pipe located where the coolingwater return bend should be. As far as I can see, you`ll not find this extension on the port side, you find a similar valve at the end of the pipe leading to the strange port circulationpump . I guess this support of theory that the circulation system has been cut in the original system and installed later.
Tore

Thanks Maciek for the great photo!
 
Tore, I have a photo of the handle from the other side. I am also happy that you think this is the shut off valve of the return cooling water from the starboard exhaust manifold, as I was hoping it was.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2013, 11:16
Maciek.
I just had a brief look at Community Forum and are astonished about what people know and discuss. I agree there are a lot of details which don`t match in all the stories on U 864. The basic is the U 864 had a schnorchel installed just before she left the yard in Germany. They spent 4 days sailing to Norway included grounding in Farsund area. She was in the Bergen submarine pen during an air raid where dambusters were used, one penetrated the roof. Just after the bergenrepair they decided to train the crew in schnorcheling prior to the departure to Japan, thus inexperienced crew doing exercises on schnorchelling off the Norwegian coast. I agree that the schnorchel mast is the first thing to be spotted rather than periscope. The theory on seasickness and zig zacking while schnorchelling I have never heard of. The talks and theories about supercharger is  strange and not worth to comment.
I guess U 864 was exercising the inexperienced crew on schnorchelling, the noise picked up by the sonar of HMS Venturer, probably not experienced in diesel sound while training schnorchelling ( they would not use the engine with a failure). They had decided to return to Bergen for engine repair. The supercharger should not be used while schnorchelling. I believe they had stopped schnorchelling, still submerged switched to E-motors, took the usual sweep by the sonar and realised they were spotted started zigzagging heard the torpedoes were coming and  crash dived deep. This is my theory, but take it with a grain of salt, I have not read any reports on the sinking.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2013, 11:20
Simon.
Another leap  ahead, but a lot to go. Progressing every day.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jan , 2013, 04:12
Simon.
 While checking the pipesystems today I believe I have discovered a difference between the normal systemsketch and the actual cooling water pipelayout. The warm cooling waterpipe pipe from the exhaustmanifold does not lead directly to the heatexchanger nor to the pump inletpipe but to the main coolingwater crossoverpipe and enters just before the filter after the gatevalve. See systemsketch below ( I have only shown the port side). This means that the water is mixing in the crossoverpipe, if it should be used for the heatexchanger they would need an unmixed supply for the engine I don`t believe it matters if you mix it in the main supplyline or at the pump inletpipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Jan , 2013, 11:42
Simon.
 While checking the pipesystems today I believe I have discovered a difference between the normal systemsketch and the actual cooling water pipelayout. The warm cooling waterpipe pipe from the exhaustmanifold does not lead directly to the heatexchanger nor to the pump inletpipe but to the main coolingwater crossoverpipe and enters just before the filter after the gatevalve. See systemsketch below ( I have only shown the port side). This means that the water is mixing in the crossoverpipe, if it should be used for the heatexchanger they would need an unmixed supply for the engine I don`t believe it matters if you mix it in the main supplyline or at the pump inletpipe.
Tore

Tore, do you think this change is German or Norwegian?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jan , 2013, 12:17
Simon
I believe  the original yarddrawings are the to be followed. It seems to me there is a change in the lay out design at a certain time. The superstructure changed all the times why should`t the interior be refined based on experience as well. It still puzzles me the we have got the type, make and capacity of the purifier, but we haven`t seen the trace of it in any of the drawings available. I am sure we shall find out sooner or later as before.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Jan , 2013, 12:42
Tore, you may find this useful, its the outline of the floor in the engine room.

(http://img266.imageshack.us/img266/8285/new1rg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jan , 2013, 13:32
Simon.
This is pretty much as it should be. I am just wandering how it looks when all the other piping is drawn in :D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Jan , 2013, 17:48
Tore, here a small test example of the floor plating between the two engines, does it look Ok?

(http://img221.imageshack.us/img221/4206/flooring.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jan , 2013, 10:22
Simon.
 This is just the way I remember it! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jan , 2013, 12:28
The more I  study drawings and pictures the more I am fascinated by the developments and changes to the VII Cs, howewer it is not so easy time fix the various changes. Right now I am investigating when various changes in the engineroom. 
 The dieselengines were originally direct reversible. At a certain point this was changed into a non reversible version. This is clearly visible on photos  when the vertically fitted reversing cylinder at the maneuvering stand is removed. Does anybody have information when the change was done.
The most common way of maneuvering submarines were by the E-motors. The German navy preferred to have maneuvering by diesels for quite a time. It required a fairly large complication to the diesels, was slow and used a lot of air. I never understood why they had such engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Jan , 2013, 17:04
Sorry, just more pipes ;D ;)

Tore, added the new exhaust to crossover pipe.

(http://img21.imageshack.us/img21/849/new2qc.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2013, 00:07
Simon.
I believe the system so far is OK. Quite a reseach lays behind this layout as the system deviate considerably from the available systemsketches which I guess are from the early 40 ties. Your layout is more as the U 1308 would look like I should say. But there are more spaghetti to be put in the bowl! ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Jan , 2013, 00:21
Simon.
I believe the system so far is OK. Quite a reseach lays behind this layout as the system deviate considerably from the available systemsketches which I guess are from the early 40 ties. Your layout is more as the U 1308 would look like I should say. But there are more spaghetti to be put in the bowl! ;)
Tore

Imagine what it looks like under the floor in the Control Room :o :o
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2013, 02:06
Simon.
The engineroom space under the foorplates is deeper and the stack of pipes on top of each other are higher . The physical topview would be a challenge to read and the sideview possibly a bigger challenge to draw.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2013, 02:12
Simon.
I hope to have my suggestions for the revised aux coolingwater details as well as the luboil ready by tonight. We shall have deviations from the systemsketches here as well I am afraid. ;) :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Jan , 2013, 21:57
Auxiliary Cooling Water Pump

(http://img842.imageshack.us/img842/3721/91619551.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Jan , 2013, 01:21
Auxiliary Lubricating Oil Pump Drain Valves

(http://img339.imageshack.us/img339/850/new1bk.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jan , 2013, 07:59
Simon.
Looks fine to me.  I haven`t checked, but it migth be it is funnel and  connection the to collectingtank as you would`t like to drain lube-or fueloil directly into the bilge. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jan , 2013, 08:29
Auxiliary Cooling Water Pump

(http://img842.imageshack.us/img842/3721/91619551.jpg)
Simon.
The aux coolingwater pump looks fine as well. I don`t know if you want at this point to introduce the connection to the handcoolingpump,suction connection to the fuelcollecting tank and anticorrosion cock. In that case it is only the connection from the valvechest to the E-room which remains before the whole system is ready. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jan , 2013, 08:42
Emergency luboilpump/ fuel transferpump.
Simon very wisely introduced above two drainvalves into the aux. luboil/ fueltransfer pumpsystem. As some might have noticed it is  unusual to have two drainvalves placed in such a way. The reason would be that this pump is handling both lubeoil and fueloil and you wouldn`t have any residue of the other in the pump when shifting to another fluid.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Jan , 2013, 10:41
Simon.
Looks fine to me.  I haven`t checked, but it migth be it is funnel and  connection the to collectingtank as you would`t like to drain lube-or fueloil directly into the bilge. 
Tore

Tore, a very good point! I check plate 9 and it looks like there a hose thread connection on the end of the valves.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Jan , 2013, 12:28
Auxiliary Cooling Water Pump

(http://img842.imageshack.us/img842/3721/91619551.jpg)
Simon.
The aux coolingwater pump looks fine as well. I don`t know if you want at this point to introduce the connection to the handcoolingpump,suction connection to the fuelcollecting tank and anticorrosion cock. In that case it is only the connection from the valvechest to the E-room which remains before the whole system is ready. ;D
Tore

Tore, suction line to the hand cooling pump. Could not found the original German alignment for this line, so best guess :-)   

(http://imageshack.us/a/img10/151/new2bo.jpg)
Fig. 2. Below floor.

(http://imageshack.us/a/img441/6875/new4x.jpg)
Fig. 2. Above floor.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jan , 2013, 13:55
Simon.
Handcooling pump pipe.
This is not far away from what it should be. I guess there were slight deviations between the various boats. When I, after a couple of years on U 995  KNM Kaura, changed to U 926 KNM Kya, I noticed very much the differences, so I guess you have some play margins.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Jan , 2013, 14:03
Simon.
Handcooling pump pipe.
This is not far away from what it should be. I guess there were slight deviations between the various boats. When I, after a couple of years on U 995  KNM Kaura, changed to U 1202 KNM Kya, I noticed very much the differences, so I guess you have some play margins.
Tore

That very interesting, I would not imagine there was much different. I would had believe all the pipes and valves were in the identical places.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jan , 2013, 15:15
Simon.
Correction KNM Kya was U 926. I seems to remember the   U 926 KNM Kya and U 995 KNM Kaura had relatively small differences,  the U 1202 KNM Kinn  was a bit more different from U 995. All three built at different yards in 1943.
U 995 was built at Blohm & Voss, Hamburg, U 926 was built at Neptun Werft Rostock AG  and U 1202 at F.S. Schichau Werft, Danzig.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Jan , 2013, 06:22
Simon.
It strikes me that all the wooden handles on the handpumps of U 995 have been removed. The pumps were of the old fashioned type having a fairly large wooden handle a indicated on the sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Jan , 2013, 01:55
Hi Tore

All this well down here in the Southern Hemisphere, just needed a break from drawing and also needed to catchup on so other work.

Boatyards should be reopen next week.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Jan , 2013, 04:53
Simon
Good to hear! Lucky you in the Southern Hemisphere having summer. Here right now, snow and freezing - 20 Centigrades. The surveyor is ready for the reopening of the yard.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Jan , 2013, 12:21
Hi Tore

Just a question about pipe sizes. I would had thought that the low pressure feed to the Hand LO pump (Purple Arrow) would be larger then the return (Green Arrow) from the Hand LO pump.

(http://img96.imageshack.us/img96/7416/img1808pa.jpg)

(http://img4.imageshack.us/img4/2755/new2mu.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Jan , 2013, 14:14
(http://imageshack.us/a/img844/9232/new1pm.jpg)
Fig. 1. Below deck.

(http://imageshack.us/a/img707/4733/new2cg.jpg)
Fig. 2. Above deck.

(http://img9.imageshack.us/img9/3513/new4ru.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2013, 14:45
Hi Tore

Just a question about pipe sizes. I would had thought that the low pressure feed to the Hand LO pump (Purple Arrow) would be larger then the return (Green Arrow) from the Hand LO pump.

(http://img96.imageshack.us/img96/7416/img1808pa.jpg)

(http://img4.imageshack.us/img4/2755/new2mu.jpg)


Hi Simon.
Luboil system.
The purple pipe is only the suction pipe to the handpump whereas the green pipe is the main supply from the electrically driven aux luboilpump as well as the discharge pipe from the handpump. The green pipe has to be fullsize mainengine luboilsupplypipe. The handpump is only a primingpump f.i. when turning the engine during maintenance etc.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2013, 00:06
Simon
Luboil system
Further to my remark on the hand lub oilpump, I guess you shall find the dischargepipe from the hand pump has a smaller diameter until it enters the pipeline from the aux. luboil pump to the distributionchest port and starboard main engine system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2013, 00:27
Simon.
The aux. luboil pump suction pipes from the luboil system and storagetanks seems OK to me.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2013, 11:24
Simon
Luboil system
Further to my remark on the hand lub oilpump, I guess you shall find the dischargepipe from the hand pump has a smaller diameter until it enters the pipeline from the aux. luboil pump to the distributionchest port and starboard main engine system.
Tore

Tore, just checking are you talking about this section of pipeing (Orange smaller diameter & Red larger diameter pipes)?

(http://img19.imageshack.us/img19/7657/new2ct.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2013, 12:16
Simon.
Yes this is the system . In addition you have of course the other small diameter pipes taking hand pump suction from the luboil storagetanks port and starboard as shown on the sketch below.
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2013, 14:34
Update of Cooling Water Piping


(http://img17.imageshack.us/img17/4725/new12w.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2013, 14:53
Simon.
 Looks fine, you have probably the seaweedblowing on another layer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2013, 14:57
(http://imageshack.us/a/img844/9232/new1pm.jpg)
Fig. 1. Below deck.

(http://imageshack.us/a/img707/4733/new2cg.jpg)
Fig. 2. Above deck.

(http://img9.imageshack.us/img9/3513/new4ru.jpg)

Breaking the laws of physics!
  ;D

Just realise that the pipe going to the oil tanks were occupying the same space as a cooling water pipe :o so I have fixed the alignment.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2013, 15:00
Simon.
 Looks fine, you have probably the seaweedblowing on another layer.
Tore

Have yet to add this layer (seaweed blowing) to the drawing, for some reason I have been putting it off  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Jan , 2013, 18:34
Updated lines to and from LO Hand Pump
(http://imageshack.us/a/img200/3226/new2.jpg)
(http://imageshack.us/a/img839/4885/new4u.jpg)

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Jan , 2013, 23:36
Simon
This pipe lay out should work. The distribution chest midship ( luboil to port and starboard engines) is a nightmare of pipes stacked on top of each other. It shall be  a challenge to accommodate the dischargepipe from the aux. luboil pump into this crows nest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2013, 06:18
Luboil handpump suction from storage tanks.
I am not 100% sure, but I assume the smaller suctionpipes of the handpumps connects to the main suction pipes from port and starboard storagetanks somewhere before the two portside valves shown on the picture below, the two small suctionpipes goes to the stb and comes up underneath the black table (driptray) just below the handpump. I guess you should find the changeovercock ( port/stb storagetanks) right under the table as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Feb , 2013, 14:41
Tore, here my estimate (in red) of the suction lines from the post & starboard to the LO Hand Pump with valve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2013, 00:05
Simon.
I guess the chief pipelayout engineer would have approved this ;D . Just a maintenance remark, the gatevalve in the seawater crossover pipe has to have access for being removed. I haven`t seen the sideview drawing, but just be aware that nuts and bolts need space when being removed, so place the pipeconnections bearing that in mind.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Feb , 2013, 12:10
Simon.
I guess the chief pipelayout engineer would have approved this ;D . Just a maintenance remark, the gatevalve in the seawater crossover pipe has to have access for being removed. I haven`t seen the sideview drawing, but just be aware that nuts and bolts need space when being removed, so place the pipeconnections bearing that in mind.
Tore

Hi Tore

This morning while realigning the pipes that runs to the LO tanks around the gate valves in the seawater crossover pipe I noted they wrong. I previously believe these pipes went over the cooler, but they run under the cooler. Below are the update drawings.

Q1. How often would you need to remove or have need access to the gate valve in the seawater crossover pipe?

Q2. Would the handle be removed on valve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2013, 12:51
Simon.
This is better. Gatevalves are very reliable and for routine maintenance I would estimate 6 years between each dismantling, however the rule is that for essential valves you should be able to open up and repair whenever nessecary. the C2 handle is removable and would cause no problem..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2013, 13:40
Simon
Luboil filters.
Knife filters previously discussed.
Your question of today. The  knife filters are not only fuelfilters, but are sometimes used for finer  filtration of luboil. On the picture below you see a larger modern filter having an electric motor on the top doing the rotation. In the case of marine execution in the 1940 years I guess this would be carried out by a handle on the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2013, 14:18
Simon
Luboil filters.
Knife filters previously discussed.
Your question of today. The  knife filters are not only fuelfilters, but are sometimes used for finer  filtration of luboil. On the picture below you see a larger modern filter having an electric motor on the top doing the rotation. In the case of marine execution in the 1940 years I guess this would be carried out by a handle on the top.
Tore

Thanks Tore.

I was just looking on the net to see that a filter look like :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2013, 14:44
Simon
Luboil filters.
Knife filters previously discussed.
Your question of today. The  knife filters are not only fuelfilters, but are sometimes used for finer  filtration of luboil. On the picture below you see a larger modern filter having an electric motor on the top doing the rotation. In the case of marine execution in the 1940 years I guess this would be carried out by a handle on the top.
Tore

Here my 3rd review of this pipe ;D Putting in the piping to the filters now.

(http://img812.imageshack.us/img812/7862/new1ms.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2013, 15:56
Tore, on Plate 14: Engine lubricating oil system, what is symbol over the filter? Is it a collecting funnel symbol?

http://www.uboatarchive.net/U-570Plate9.htm (http://www.uboatarchive.net/U-570Plate9.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2013, 23:28
Simon.
I guess the symbol over the finefilter is a differential pressuregauge. The gauge measure the pressure in the pipeline before and after the filter thus  indicating the resistance and when the filter has to be cleaned. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2013, 23:40
Simon
Luboil filters.
Knife filters previously discussed.
Your question of today. The  knife filters are not only fuelfilters, but are sometimes used for finer  filtration of luboil. On the picture below you see a larger modern filter having an electric motor on the top doing the rotation. In the case of marine execution in the 1940 years I guess this would be carried out by a handle on the top.
Tore

Here my 3rd review of this pipe ;D Putting in the piping to the filters now.

(http://img812.imageshack.us/img812/7862/new1ms.jpg)

Simon.
Looks promising. a good thing you are colourmarking the pipes! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 00:10
Simon.
I guess the symbol over the finefilter is a differential pressuregauge. The gauge measure the pressure in the pipeline before and after the filter thus  indicating the resistance and when the filter has to be cleaned. 
Tore

Thank Tore.

I thought they were pressure gauges. They must be under the decking next to filter?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 00:14
Simon
Luboil filters.
Knife filters previously discussed.
Your question of today. The  knife filters are not only fuelfilters, but are sometimes used for finer  filtration of luboil. On the picture below you see a larger modern filter having an electric motor on the top doing the rotation. In the case of marine execution in the 1940 years I guess this would be carried out by a handle on the top.
Tore

Here my 3rd review of this pipe ;D Putting in the piping to the filters now.

(http://img812.imageshack.us/img812/7862/new1ms.jpg)

Simon.
Looks promising. a good thing you are colourmarking the pipes! ;D
Tore

The piping around the LO filters would be the most complex I have drawn!
 
Its hard to get it to fit around all the other LO Piping and then the Cooling water piping ::) ::)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 00:24
Simon
In addition we have still smaller pipes to gauges, drains etc waiting for you. Just think about the poor people who had  to maintain the various components. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 00:29
Simon.
Filtergauges.
I cannot see the differential gauges on the manometerpanel so I guess if you place the gauges under the floorplating it would be OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 00:34
Tore, here a sneak preview. Will finish it tomorrow, off to bed now :)
 
How does the filters look liker?

(http://imageshack.us/a/img24/7569/new1zp.jpg)

(http://imageshack.us/a/img824/5502/new2ob.jpg)

(http://imageshack.us/a/img69/1281/new3we.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 00:35
Simon
While we are on the luboilfilter. The filters should be able to be drained for impurities. Hopefully you should be able localize a drainpipe with valve (cock) to the collecting tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 00:40
Simon.
Luboilpiping.
Your new piping layout seems to be your normal high standard. I`ll  have a closer look at it during the day.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 05:46
Simon.
Luboil piping/filter.
I have checked you last lay out and believe everything is fine. I am impressed by the way you are able to squeeze in the aux. luboilpump dischargepipe. A small remark as to the cover of the luboil filter. You have generously fitted the cover of the casing with 16 bolts, I guess 8 would do. I believe the casing would be tested with some 6 bar and the relief valve would open at 4, so remember the poor maintenance fellows. :D Looking forward to see the complete system, must be impressive.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2013, 08:57
Simon.
Differential manometer luboilfilter.
I just checked a photo of the instrument panel on the engine page of u historia. If you look at that photo you`ll find a manometer marked 3 and on the nameplate it says . Schmier
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 12:59
Tore, great spotting on the pressure gauges, you can trace the piping down to the filters http://www.360cities.net/image/submarine-u-995-machine-room#333.75,7.18,38.9 (http://www.360cities.net/image/submarine-u-995-machine-room#333.75,7.18,38.9)

(http://imageshack.us/a/img39/4718/new4y.jpg)

(http://imageshack.us/a/img201/9185/new6u.jpg)

(http://imageshack.us/a/img401/406/new7r.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 04 Feb , 2013, 14:58
Wonderful find Simon! You have  a good eye!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 15:47
Sorry, just more pipes ;D ;)

Tore, added the new exhaust to crossover pipe.

(http://img21.imageshack.us/img21/849/new2qc.jpg)

Tore, I just noted that the pipe colour code for the cooling water to the E Room/Torpedo Room is worng, it should be Green-Yellow-Green not Green-Violet-Green.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 20:50
Tore, where is the yellow line in real life? Does it run on top to the engine?
(http://img22.imageshack.us/img22/1041/new2ju.jpg)

I was able to find the orange line :)
(http://img59.imageshack.us/img59/6875/new4x.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2013, 20:52
A small remark as to the cover of the luboil filter. You have generously fitted the cover of the casing with 16 bolts, I guess 8 would do. I believe the casing would be tested with some 6 bar and the relief valve would open at 4, so remember the poor maintenance fellows. :D

 ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Feb , 2013, 00:30
Tore, here today update.

I also was able to corrected the openings into the OL Tanks.

(http://img687.imageshack.us/img687/5089/new2rk.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 00:58
Simon.
3 bar luboil supply to servo.
A good question. I would have thought the supplypipe runs below the floorplating inboard. However if you see the pipeconnection on the servo it looks as if the pipe enters the servo from outboard. I have not been able to trace the pipe along the engine for sure. May be you have more pictures to check.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 01:20
Simon.
Orange luboilpipe.
Yes this is the pump bypassline with shut of valve.  The other end should connect to the 3 bar servo supply which seems to go  inboard as I thought, but it still does not match the connection to the servo coming from outboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 01:30
Simon.
Your last updated drawing.
Now you are entering into the small pipe stuff where the sky is the limit, ;D  the manometer pipes are OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Feb , 2013, 02:00
Simon.
Your last updated drawing.
Now you are entering into the small pipe stuff where the sky is the limit, ;D  the manometer pipes are OK.
Tore

Thinking about adding the spider webs next  ;D ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 05:43
Watch out  don`t get caught in the web. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 13:49
Simon.
3 bar luboil supply servo.
I am happy you found the supply pipe going on the outboard side of the engine. Your suggested revised systemsketch is of course according to you find. I have below indicated how I guess the details of the servo might be. After the branch off to the Roots blower bearings, I guess they enter on both sides, the supply pipe enter the servo as shown on the drawing. The two drainpipes runs from the servo separately ( not to have any pressure interference) and join further the maindrain from the blower before entering the systemtank valvechest and into the tank.The oil from the servo is not contaminated so I don`t believe it enters the dirty oil tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Feb , 2013, 14:20
(http://img713.imageshack.us/img713/4301/pipe4.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Feb , 2013, 23:50
Simon
The maintance staff would thank you for the new luboil filtercover and are happy you have some 75 cm between the floorplate and gatevalve of the coolingwater crossoverpipe under the valvechest. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 00:43
Tore, are the blue highlighted areas the sea water cooling pipes within the exhaust?

(http://img577.imageshack.us/img577/5541/f461.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 00:51
Tore, I noted that on U-995 and the shipyard drawings there is a release valve for the cooling water at the end of the exhaust pipe. However, it not marked on the Design and Specification Book, plate 13. Do you think the release valve was added to the system sometime after 1940?

http://www.uboatarchive.net/U-570Plate13.htm (http://www.uboatarchive.net/U-570Plate13.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2013, 01:13
Simon
Exhaust coolingwater.
I don`t think so Simon. I`ll check and see if I can figure out this.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2013, 01:22
Simon.
I guess the reliefvalve of the exhaust manifold was installed on schnorchel boats. We had a few times experiences while schnorchelling that the relief valve opened as a consequence of dipping the mast and the exhaust backpressure became excessive. The engine room was filled with black unpleasant exhaust.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 01:46
Simon.
I guess the reliefvalve of the exhaust manifold was installed on schnorchel boats. We had a few times experiences while schnorchelling that the relief valve opened as a consequence of dipping the mast and the exhaust backpressure became excessive. The engine room was filled with black unpleasant exhaust.
Tore

Thanks Tore. I thought the relief valve was for the cooling water.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2013, 06:07
Simon
Main engine exhaust manifold.
The crossection drawing shows engine looking towards the forward end , see drawing below, the reversing cylinder up front is removed on the later engines. There are no indications of any objects or restriction flanges towards aft and I can not see any reason why such restricton in exhaust manifold diameter should be justified.
If you look at the photo below showing the forward exhaust manifold endcover there are two reasons why this is not the main endcover, only 6 small fixing bolts whereas on the exhaust manifold flanges you have 12 fairly sizeable bolts, there is obviously a large hole in the cover for the reliefvalve. Based on this my assumption would be the shown forward endcover is just a protection cover and behind is the cast double wall cooled end dome being the real cover. In the end dome is an inspectioncover having a smaller diameter than the  exhaust manifold and the drawing shows this inspection cover.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 11:26
Tore, just double checking, the exhaust manifold is double wall with the cooling run in the outer ring?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2013, 14:07
Simon.
The exhaustmanifold is casted like a double wall pipe and  the coolingwater flows between the outer and inner walls, at the forward end piece I guess the casting could make a double bottom, like a bottom of a glass thermo bottle. In this bottomplate is the inspection opening having a smaller inspection plate. A possible alternative could be that an uncooled steelplate is just flanged to the manifold, that plate would have a smaller inspection opening covered by a steelplate. The outer visible plate with smaller bolts provide a heatprotection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 14:13
Simon.
The exhaustmanifold is casted like a double wall pipe the coolingwater flows between the outer and inner walls, at the forward end piece I guess the casting makes a double bottom, like a bottom of a glass thermo bottle. In this bottomplate is the inspection opening having a smaller inspection plate. The outer plate with smaller bolts provide a heatprotection.
Tore

All make sense now :)
I had been imagining it was the other ways round :-[
What was why I been asking all these questions about the exhaust manifold, as I could not get my head around it ::)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2013, 14:51
Simon.
That may be.  I think I have seen a drawing of the compensating box in the bottom of the saddletank. See below,  I made a rough pencil sketch indicating where to look for it you have more materials to look into than me.
Tore



This could be that pipe on the U-534

(http://img26.imageshack.us/img26/9379/new3h.jpg)
Simon. Interesting detail, it certainly could be the box, I only miss the pipe out of the box. The idea was to have a buffer preventing contamination into the compensating system. Howewer the most important pipe for that was the fueloil venting pipe  which ended some 10 cm from the bottom of the ballast/fueltank. When fuelling, the ventcock was open and a guy watched the water coming out and stopped the fuelling when he discovered fuel coming out, but as the pipe ended 10 cm above the tankbottom you could never force fuel into the compensatingpipe as the fuel was flowing through the ventpipe leaving some 10 cm of water in the tankbottom saving the compensating system. This was  before pollution and environment questions was a topic. Anyhow see to it that your fuel ventingpipe is not leading all the way to the bottom ;D
Tore

Simon.
Compensating expansionbox.
As to my yesterdays post I have given it a second thought. I believe the device and connecting pipe on the picture is too small for being the box. Estmating the capacity of the tank to be some 12 tonnes of fuel I guess it should have a volume about 150-200 liters ( almost an oilbarrel).
Tore

Tore, I was thinking about the small box shape at the bottom of the saddle tank and next to the pressure hull could it be the echo sounder?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2013, 00:56
Simon.
Echosounder
I don`t know the details of a IXC very well, but this is an unusual place for a echosounder, I really could not say for sure what the "box" is.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Feb , 2013, 03:33
Tore, I was thinking about the small box shape at the bottom of the saddle tank and next to the pressure hull could it be the echo sounder?


I'll check in the evening, but as I remember, echo-sounding transmitters and receivers were located rather near the keel. Hard to say what it can be...


--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2013, 12:16
Updated exhaust manifold

(http://img837.imageshack.us/img837/6687/engineroom4.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2013, 13:13
Simon.
As usual everything looks very good. I am a bit doubtful to the exposed manifold flanges. If I remember well they were covered by asbestos!!cushions and protected by an steelsheet plate, see yarddrawing. The reason for That is the uncooled bare flanges gets very hot and a possible bursted HP fuelpipe might squirt fuel hitting the flange which immediately ignites.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2013, 19:59
Simon.
As usual everything looks very good. I am a bit doubtful to the exposed manifold flanges. If I remember well they were covered by asbestos!!cushions and protected by an steelsheet plate, see yarddrawing. The reason for That is the uncooled bare flanges gets very hot and a possible bursted HP fuelpipe might squirt fuel hitting the flange which immediately ignites.
Tore

Thanks, Tore.

I will update my drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Feb , 2013, 23:16
Hi,
Tore, I was thinking about the small box shape at the bottom of the saddle tank and next to the pressure hull could it be the echo sounder?


I'll check in the evening, but as I remember, echo-sounding transmitters and receivers were located rather near the keel. Hard to say what it can be...


Eberhard R
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2013, 23:54
Hi,
Tore, I was thinking about the small box shape at the bottom of the saddle tank and next to the pressure hull could it be the echo sounder?


I'll check in the evening, but as I remember, echo-sounding transmitters and receivers were located rather near the keel. Hard to say what it can be...


Eberhard R
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 00:19
Tore, I am no expert but this look like a U-boat LO Purifier?

(http://img145.imageshack.us/img145/3918/new3n.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 00:29
Simon
I just was going to post the same assumption. Macieks find that there are sender and receiver at different locations in the saddle fuel/ballasttanks strongly indicate this is indeed the echosounder. As there are two similar boxes at different places make this more probable  than a possible deviation from the location mention in the book. Below is the pictures of the two locations, to me it looks like port side just aft of the controlroom and starboard side of the engine room based on my VIIC ideas. .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 00:36
Simon.
Purifier.
Your picture could very well be a purifiermodule.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 00:39
Hi Tore

Not part of the Engine Room, but part of the Cooling-water system, I found the Hull valve in the E. Room  :) :) :)

(http://img20.imageshack.us/img20/8954/new4p.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 00:40
Simon.
Purifier.
Your picture could very well be a purifiermodule.
Tore

 :) :)

I found it on U-505

http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html (http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 00:52
Simon
As I said I am not at all conversant with the IXC so you have to take everything from me with a pinch of salt on that subject. Anyhow I am convinced it is the echosounder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 01:01
Simon
Purifier.
As you see it is a fairly sizeable piece of equipment I believe you can see the waterheater fitted on the module as well. You certainly would have seen it in the engine room.  It just confirms that on later VIICs and VIIC/41 they did away with the purifier and installed better filters instead.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 01:26
Simon
Purifier.
As you see it is a fairly sizeable piece of equipment...
Tore

I imagine it was one of the weight-saving they found between the Type VIIC and the VIIC/41. They were able to make the VIIC/41 11.5 tons lighter, which they later put back in the pressure hull.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 01:38
Simon.
That could be, but I am pretty sure our two VIICs U 926 and U 1202 did not have the purifier as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 12:20
Simon.
That could be, but I am pretty sure our two VIICs U 926 and U 1202 did not have the purifier as well.
Tore

Hi Tore,

I was not meaning the changes were only for the Type VIIC/41's and I am sure the late war VIIC's got as many of the update also.

Tore, when do you think they started to removing the reversing cylinder? It must be sometime after 43??

I have noted a huge different in the layout of the forward end of the engine between the engines with and without the reversing cylinder. I been using the wrong layout (with a reversing cylinder) :( So I will need to charge my drawing around.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 13:07
I could not help myself, I had to add a little more detail to the drawing. Check out the new fuel filter markings ;D

(http://img560.imageshack.us/img560/1376/new1zs.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 13:21
Simon
Based upon my experience with our 3 VIICs-VIIC/41 I would imagine  your had  major changes in the uboats delivered from the yards as from July 1943. U 995 our oldest VIIC/41 delivered July 1943 and the two other delivered end 1943 had nonreversible engines, removed purifier etc. That would not eliminate possible earlier changes. Installation of the schnorchel was carried out later, for U 995 it was just completed at the end of the war May 1945.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 13:24
Simon
Your fuelfilters looks marvelous. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2013, 14:18
Simon
Reversing mainengine.
The conversion to a nonreversible engine was really not a major change. They removed the reversingcylinder( the large cylinder),the reversing slide valve ( the small cylinder) and pipings. The tachometer and enginetelegraph as well as the reversing nameplate (removing the handle) was not removed or changed as can be seen on the photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 16:35
New layout without reversing cylinder.

You can see the main change the Germans did, they moved the air starting valve and the fuel filters into alignment of the base plate of the missing reversing cylinder.

(http://img543.imageshack.us/img543/451/new1ln.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2013, 21:37
Tore, here a small detail that we miss. Small metal box clamps holding the fuel lines on top.

(http://img835.imageshack.us/img835/8906/new1qh.jpg)

(http://img11.imageshack.us/img11/3116/new2eb.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2013, 00:27
Simon.
HP fuel pipeclamps.
I you are right. Allthough they look like being insignificant they were important as they prevented vibrations which might lead to breakage and firehazard as previously mentioned.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2013, 01:08
Simon.
Being at your revised drawing I shall introduce you to the air induction system not discussed before, I guess it would keep you busy during the weekend. ;D 
The air induction is at moderate revs and load normal aspiration eg. the engine sucks the air from the engineroom to each individual cylinder. When the load and revs reach a certain level ( I believe 390 rpm) you had to switch in the double cone clutch for the Roots blower. The air is then at an overpressure supplied via an airduct from the blower to a common manifold connected to the inletvalves. This means that the direct individual air induction from the engine room to the inlet valves have to be shut. All this is done by a handle placed outboard and seen on the picture below. The handle was combined with the reversing handle, on the non reversible engine the handle is fitted as shown. By moving the handle you are turning a rod alongside the engine, the rod rotates and shuts the natural aspiration inlets and at the same time switch in the Roots blower clutch as can be seen on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2013, 06:44
Simon
Induction air system
Having read my post this morning I realize I should probably have expressed my shelf a bit clearer. The normal aspirated air supply enters the air manifold through two inlets in the manifold before going to the inletvalves. These two inlets are shut when the blower is connected by the blowerclutch handle. The fuel handle can not be moved to a higher preset filling unless the blower is engaged. Interlock prevents the startinghandle to move unless the blower is disengaged. All these  interlocks makes an intricate mechanical system of rods and levers which I don`t believe you should bother about. As to the reversible engine. It is no direct connection between the reversinghandle and the blowercoupling handle except the interlock preventing the engine to be run astern with blower engaged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2013, 07:26
Simon.
Exhaustmanifold protection.
I see you have put in the exhaustmanifold protection around the flanges. In spite of your clamps, vibrations sometimes caused the hp fuel line to break at the fuelinjector inlet and the fuel squirted right on to the flange area which you have now protected. I could not resist using your nice drawing to illustrate the situation. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Feb , 2013, 12:55
Hi Tore,


I wonder about one thing. On the photo below (from U 570 diesel engine room) there are visible two engine order telegraphs and two pairs of shaft revolution indicators (one pair next to telegraphs and the other slightly behind the wheel of the main induction valve). I suppose, that the revolution indicators in the front are for diesel engines, while these in the back - for the propellers shaft, right?
(http://uboatarchive.net/U-570Photo26.jpg)

(http://uboatarchive.net/U-570Photo26.htm)


Second thing - in this document: http://uboatarchive.net/Manual.htm (chapter Rudder order telegraph and rudder angle indicator system) it is said, that in diesel engine room was one indicator of the main rudder position. I was not able to locate it in the diesel engine of U 995. By analogy to the U 505, I would suppose, that it had to be on the fuel oil gravity tank...
Or maybe it was not installed at all? I don't think it has to be necessary in the diesel engine room...


(http://img195.imageshack.us/img195/9889/u505dieselenigneroom.jpg)


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2013, 13:33
Maciek.
You are right the rpm meters on the fuel daytanks, (headertanks) are the shaft rpm meters. I really can not remember any rudder angle indicator in the diesel room as you know a rudder indicator was in the E-room. In general you would not need to have a rudderindicator in the dieselroom allthough it would have been handy as at big rudder angle you would notice a heavier load on the engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Feb , 2013, 03:40
Simon.
Macieks photo from U 570 above shows the instrument panel as it used to be, crisp, with unpainted brass cocks and moderate painting not spotted with red paint as you se on the present U 995. I believe  you could very well use the above panelpicture as a model for your instrument panel drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Feb , 2013, 20:47
Simon
Induction air system
Having read my post this morning I realize I should probably have expressed my shelf a bit clearer. The normal aspirated air supply enters the air manifold through two inlets in the manifold before going to the inletvalves. These two inlets are shut when the blower is connected by the blowerclutch handle. The fuel handle can not be moved to a higher preset filling unless the blower is engaged. Interlock prevents the startinghandle to move unless the blower is disengaged. All these  interlocks makes an intricate mechanical system of rods and levers which I don`t believe you should bother about. As to the reversible engine. It is no direct connection between the reversinghandle and the blowercoupling handle except the interlock preventing the engine to be run astern with blower engaged.
Tore

Tore, how does my Induction air system look like?

It was hard to draw, as I have no photo's and a drawing from only one view :(

(http://img26.imageshack.us/img26/6687/engineroom4.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Feb , 2013, 01:17
Simon
The overall picture is good. I guess there are not many details to be shown on a top view, when the Roots blower is fitted it would help together with a frontview. I`ll keep looking and see if I can provide with more details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Feb , 2013, 09:44
Simon.
Below a cossection of the engine showing the airmanifold in superchargermode and the rod engaging the clutch and shutting the the natural aspiration inlet.
Unfortunately I do not have any drawing or photo showing the manifold may be somebody could help?. ::)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 12:39
I am looking in my (admittedly limited) sources Tore. I used to blow stuff up. I do not do that now... but I will try and see if I have anything to offer that is positive my friend...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Feb , 2013, 12:47
I used to blow stuff up. I do not do that now...

I blow up stuff also...but only snow ;D

Christopher, have you ever made any in holes in snow, or only in metal?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 15:36
Simon....
I learned much about blowing stuff up in S.korea... and blew up snow there.. It was winter there... and I admit I focused on hardware that N. Korea was using.... then I was sent to the Iraqi venue.. I am sure you would like Det Courd... orange line...with an electric explosive cap...
we sent snow to the bottom of he casm where we needed it. We sent metal to the heavens when we needed to. As a Marine, focused on my nation's goals... I did my work...


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 15:38
If one is not military... one need not actually know about methods of sapping, or explosive devices.

moving on... Politics are not this forums goals. Not political here.
Christopher.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Feb , 2013, 16:08
Simon....
I learned much about blowing stuff up in S.korea... and blew up snow there.. It was winter there... and I admit I focused on hardware that N. Korea was using.... then I was sent to the Iraqi venue.. I am sure you would like Det Courd... orange line...with an electric explosive cap...
we sent snow to the bottom of he casm where we needed it. We sent metal to the heavens when we needed to. As a Marine, focused on my nation's goals... I did my work...

We have orange Det Cord (about 8 g/m) on the hill. I do not used it too much, mostly to link big ANFO charges together.
 
We are not allow to use electric explosive cap.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 16:16
low shock/thermic value... resonating in hard rock... it would shake the rocks... the snow would come down
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 16:23
Simon. I have used orange det courd for many purposes. I have blown up simple telephone poles with it. I have wrapped it around the turret races of supposedly high-end tanks and popped them off. I have cut engine blocks in two, have severed axles and wheels, and have cut tank barrels from their casting mounts.I have sent too many pine too their graves...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 16:31
I do not do that now.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 11 Feb , 2013, 18:24
sorry Simon. I did not mean to sound like I was going off on you.  I am sorry.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Feb , 2013, 11:20
Hi Tore

Here a small detail added, yesterday I found a better picture of the top of the rocker arm.

(http://img19.imageshack.us/img19/6687/engineroom4.jpg)
Fig. 1. Updated drawing (left), Old drawing (right).

(http://img546.imageshack.us/img546/6918/new1qv.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2013, 12:17
Simon
You are really going into the really tiny stuff, may I at this point reintroduce the adjusting nut locking string and the valverod shaft spring locking ring. I mean you have been inquiring about the lockingplates ;D . I guess it is the small details which makes it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Feb , 2013, 13:50
Tore, what do you think the missing label on U-995 looks like? You can see it on U-570. Would be cool to add this detail.

(http://imageshack.us/a/img441/4592/new1e.jpg)
(http://imageshack.us/a/img854/6739/u570photo28.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Feb , 2013, 13:53
Simon
You are really going into the really tiny stuff, may I at this point reintroduce the adjusting nut locking string and the valverod shaft spring locking ring. I mean you have been inquiring about the lockingplates ;D . I guess it is the small details which makes it.
Tore

Thanks Tore.

I have the spring locking rings on the fuel rod shaft, but I have miss them on valve rod, will update my drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2013, 14:46
Simon
Apart from it looks like being a bit shorter and higher, I guess the text would be the same so why not fit it.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Feb , 2013, 15:24
Tore, sorry I am not talking about the long narrow label.

I believe it will be the serial plate, like the electric motor drawing.

(http://img839.imageshack.us/img839/8071/electricmotorserialplat.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2013, 23:56
Simon
I got it. I have tried to read the text on the upper nameplate, but in vain. There are four lines of text, first and third a bit longer that the other. It does not look like a serial nameplate, more like an instruction, hard to say. I suggest you include both. May be you have means to decipher the text.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Feb , 2013, 00:10
Simon
I got it. I have tried to read the text on the upper nameplate, but in vain. There are four lines of text, first and third a bit longer that the other. It does not look like a serial nameplate, more like an instruction, hard to say. I suggest you include both. May be you have means to decipher the text.
Tore

Tore, you are correct. It looks more like instructions label.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2013, 00:15
Instructionplates,paintmarkings and interlocks in the engineroom.
I have very often been puzzled by the effort the germans put in instructionplates, paintmarkings and the interlocks on the machinery and pipings in the engineroom.
In those days such extensive markings was not common, as only qualified crew were operating the equipment. Having read a few article on the subject I realize it was hard for the germans to find and educate sufficient qualified crew for the rapid expanding submarine fleet and hence introduced the comprehensive interlocks and excessive markings to prevent major disaster. The extensive use of interlocks on the reversing mechanism is a typical example to the above.
In our days improved marking seems to have picked up.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2013, 07:19
Simon
The the rod for the shutting of normal aspirated air inlets and switching in the Roots blower start up front as previously shown, and continue along the engine rotating the two inletslides and then to the aft end of the blower where it crosses inwards to the doublecone clutch. I have tried to indicate this on the drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Feb , 2013, 11:51
Tore, here a sneak preview. Still have lots of detail to add.

(http://img842.imageshack.us/img842/708/new1jv.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2013, 13:53
Simon
We are entering a gray zone for me, I can not remember how the airduct from the Roots blower is entering the airmanifold. It is annoying because I my shelf dismantled the blower entirely ( some 60 years ago) :) . I have superimposed your drawing on top of a layout drawing  to figure out the arrangement. The confusion is on an appearant large ( yellow coloured ) square opening which I thought would be the inlet to the manifold. I just show you the picture may be you have more materials helping you to figure out the connection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Feb , 2013, 12:52
Tore, this is as far as I can go with the photo's I have. From this point it all estimated :(

(http://img703.imageshack.us/img703/3498/new1pi.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2013, 14:09
Simon.
Unfortunately you are right, I guess however that the next exhaustmanifold section passing the Roots blower is pretty certain. I have an idea for the inlet and output of the Roots blower, but rigth now it would be guesswork so I keep looking for documents confirming next step.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Feb , 2013, 13:09
Tore, Check this out :)

I overlay the Pressure Hull openings on the Engine Room layers. It great to see the openings matching 8)

(http://img545.imageshack.us/img545/1741/new1eo.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Feb , 2013, 13:22
Tore.

Q1. What is this (Purple)?

Q2. Why is the extra pipe on the Starborad side (Green)?

(http://img507.imageshack.us/img507/1332/pjx6bxa8.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Feb , 2013, 14:39
Tore, Check this out :)

I overlay the Pressure Hull openings on the Engine Room layers. It great to see the openings matching 8)

(http://img545.imageshack.us/img545/1741/new1eo.jpg)
Simon
Looks fine,I guess you can fit the last section of the exhaustmanifold as well, ready for hooking up the exhaustpipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Feb , 2013, 15:13
Simon
The purple marked item s are the two pneumatic motors turning the grinding device for the main exhaustvalves.
The green marked pipe could be the anticorrosion oil connection to the Junker compressor however there are valves which does not fit in. I`ll have to check and revert tomorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2013, 03:01
Simon
It was rather late yesterday trying to answer your question so I better try to rectify now. The green marked pipe system is far to large for being the anti corrosion oil pipe, I guess it is more likely belonging to the ventilation suctionsystem having a crossover to the port side and a branch to the lower stb outboard side connecting to the oxygen flask. You `ll find a better picture at the U historia seeing the connection to stb.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2013, 06:19
Simon.
Roots blower.
The Roots blower is indeed placed a bit off the centerline of the engine as can be seen on the sketch below. The off center is towards outboard and make an improvement for the airinlet as well as facilitates the connection to the airmanifold.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 13:12
Simon
The purple marked item s are the two pneumatic motors turning the grinding device for the main exhaustvalves.
Tore

(http://img849.imageshack.us/img849/6779/new1iq.jpg)

Tore, for some reason I had always thought grinding device was hand operated.
 
Looking at the photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 13:12
Simon.
Roots blower.
The Roots blower is indeed placed a bit off the centerline of the engine as can be seen on the sketch below. The off center is towards outboard and make an improvement for the airinlet as well as facilitates the connection to the airmanifold.
Tore

Thanks Tore, will update my drawing today.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2013, 13:58
Simon.
On the British report of U 570. You can read an accurate description of the exhaust valvegrinding. The muffler valves are turned by the pneumatic motors, the group exhaustvalves are handoperated and the same is the Junker compressor exhaustvalve.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 14:06
Simon.
Roots blower.
The Roots blower is indeed placed a bit off the centerline of the engine as can be seen on the sketch below. The off center is towards outboard and make an improvement for the airinlet as well as facilitates the connection to the airmanifold.
Tore

Thanks Tore, will update my drawing today.

(http://img339.imageshack.us/img339/143/new1ay.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 14:25
Simon.
On the British report of U 570. You can read an accurate description of the exhaust valvegrinding. The muffler valves are turned by the pneumatic motors, the group exhaustvalves are handoperated and the same is the Junker compressor exhaustvalve.

Tore

Tore, while searching the net for information on the exhaust valve grinding I found this. It talks about British Oberon-class submarine exhaust valve grinder :)

http://www.hnsa.org/doc/oberon/induction/index.htm (http://www.hnsa.org/doc/oberon/induction/index.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 14:26
Simon.
On the British report of U 570. You can read an accurate description of the exhaust valvegrinding. The muffler valves are turned by the pneumatic motors, the group exhaustvalves are handoperated and the same is the Junker compressor exhaustvalve.

Tore

Thanks Tore, I had a look.

Tore & Maciek, has anyone see any drawings of the exhaust valve?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Feb , 2013, 15:06
Simon
I guess you might find some details in your  own photos as this one below. I`ll check for more tomorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 15:15
Simon
I guess you might find some details in your  own photos as this one below. I`ll check for more tomorrow.
Tore

I will for sure have more questions for you tomorrow ;) In the VIIC manual it said there are four openings for the Grinding mechanism for the exhaust gas valves stb. and port. I have found 2, now looking for the other two.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Feb , 2013, 16:28
Tore & Maciek, can you guys please double check my valves.

(http://img844.imageshack.us/img844/2407/new2gs.jpg)

Blue = Exhaust gas flap valve, inboard. Valve 'P'. http://www.uboatarchive.net/U-570Plate13.htm (http://www.uboatarchive.net/U-570Plate13.htm)
Green = Pneumatic grinder
Purple = Drain valve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 00:30
Simon
Exhaust valves
Below is the normal systemsketch indicating the relevant components. The first valve is the group exhaustvalve which is situated in the peculiar cast steelcasing inside the pressurehull. It is a hinged valve which is "folded down " like a flap. You find a very good photo on u historias exhaustgas page. On this picture you see a square shaft stud marked 4 next to the hinge. On this shaft you put a lever for turning the groupvalve disc. When this valve is shut eg. the valveseats are in contact, you are moving the  handle, turning the valvedisc and thus grinding the valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Feb , 2013, 01:03
Simon
Exhaust valves
Below is the normal systemsketch indicating the relevant components. The first valve is the group exhaustvalve which is situated in the peculiar cast steelcasing inside the pressurehull. It is a hinged valve which is "folded down " like a flap. You find a very good photo on u historias exhaustgas page. On this picture you see a square shaft stud marked 4 next to the hinge. On this shaft you put a lever for turning the groupvalve disc. When this valve is shut eg. the valveseats are in contact, you are moving the  handle, turning the valvedisc and thus grinding the valve.
Tore

Tore, I still a little confuse :-[

So on the picture at u historias, No. 4 operate the grinder & No. 2 operate the hinged valve?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 01:57
Simon.
The exhaust valve are operated by two devices, the shutting and the grinding. The valve is hinged and the hingeshaft is operated by a wheel and by linkage turning the shaft and moving the valvedisc to an open/shut position. The circumference of the valvedisc has a bevelled gearrim which meshes a short worm fixed to another shaft inside the hingeshaft. This shaft can be turned either by hand ( group exhaustvalve) or pneumatic motor( muffler exhaustvalve). The worm is always in contact with the rim meaning you can rotate the disc in any position. Unfortunately I don`t have any drawing but have tried to indicate the system on the muffler valve below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 02:03
Simon
Exhaust valves
Below is the normal systemsketch indicating the relevant components. The first valve is the group exhaustvalve which is situated in the peculiar cast steelcasing inside the pressurehull. It is a hinged valve which is "folded down " like a flap. You find a very good photo on u historias exhaustgas page. On this picture you see a square shaft stud marked 4 next to the hinge. On this shaft you put a lever for turning the groupvalve disc. When this valve is shut eg. the valveseats are in contact, you are moving the  handle, turning the valvedisc and thus grinding the valve.
Tore

Tore, I still a little confuse :-[

So on the picture at u historias, No. 4 operate the grinder & No. 2 operate the hinged valve?
Simon.
I think so.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 06:26
Simon
Group exhaustvalves
The name sound perhaps a bit strange to you but is a very common Royal Navy term in the submarine service, meaning a device collecting several connections, like exhaust outlets from 6 cylinders (manifold). Down below is a photo showing the  valvewheels in the engine room for the 3 pairs of relevant exhaust valves.
The arrangement deviates a bit from British and US subs as it is adopted for using exhaust pressure for blowing the ballasttanks in semisurfaced position instead of a lowpressure electric blower as the case of other submarines. The muffler valves were used in a semi open position when blowing the tanks in order to adjust the exhaust backpressure. One disadvantage of the system was that the muffler ( dry muffler) exhaustvalve had a tendency to get carbonizes and deposits could be formed both on the valveseating as well as the gear rim and wormwheel, thus blocking the device. As this was mostly common on the mufflervalve a pneumatic motor was fitted  and the valve had to be rotated may be once a watch whereas the group exhaustvalve had a hand turning with handles and ratchets.
As you see the wheels have a bore where you could put a bar giving an extra force to the shutting moment, moreover the group exhaustvalves had a pointer for shut and open 90 degrees.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 06:47
Simon
As an addition to my last post I should perhaps mention that the engineer having divingposition in the engineroom had a remarkable technique  grinding the mufflervalves  when diving. In order to get a proper pressure on the valve disc he started the grinder some 2-4 meter submerged and got a excellent pressure.  At periscope depth however the pressure was too high and the pneumatic motor stalled. In spite of grinding we had occasional leakages but a proper drain took normally care of that. Once or twice we had to surface due to excessive leakage and a couple of times we flooded the engine via the exhaustpipe. As a rule we never started the engines without turning with open indicatorcocks and more than once water squirted out of the cocks. A disadvantage with using the pneumatic grinder was building up pressure inside the boat, at excessive grinding this could happen.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Feb , 2013, 12:31
All the drain lines seen on Plate 13 http://www.uboatarchive.net/U-570Plate13.htm (http://www.uboatarchive.net/U-570Plate13.htm) are within the pressure hull.

So, what is the 'Hull Valve Sea Water' marked as purple used for?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Feb , 2013, 12:40
Tore, I try to track the drain piping around the Exhaust manifold but I was not able to :( Too many pipes in a small area, not enough photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 13:03
Simon.
 I am not sure I understand your question. U-570 plate 13 is not easy to understand as you have sea coolingwater pipebends, anti corrosionpipes and exhaust drain connection  drawn in the same way. The main drain having connection to the sea is the valve m on plate 16 or o on plate13. This valve has to be open in case of leaking muffler valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2013, 13:18
Simon.
As to my last post I should probably say...or o marked as hullvalve on plate 13.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Feb , 2013, 07:28
Hi Tore,


I wonder about one thing: on the following image and in the document (http://uboatarchive.net/Manual.htm page 14, table Test data) are gathered engine/motors orders and corresponding RPMs and speed. I suppose, that given speeds  corresponds the orders given to both engines/motors.


(http://img823.imageshack.us/img823/630/fahrtstufen.jpg)


 The orders: Kleine FahrtLangsame Fahrt, Halbe Fahrt, Gro
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Feb , 2013, 08:26
Maciek.
We never used so many speed steps, we could use the 10 steps up. I wonder if 2HF and 2GF reflects on moving the telegraph twice indicating a certain step in increasing the revs as indicated on the board. For 3xAK this would mean you pull the handle back and forth 3 times and the diesel should run 480 revs instead of 470, but you could used the 10 revs up signal instead. As I say we did not use this kind of signals.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Feb , 2013, 08:48
Simon
As we have hardly any proper photo or drawing of the group exhaustvalve, I have tried to figure out by a modest sketch how the group exhaustvalve is constructed.
The housing is of course a full pressure proof steel casting containing the valve, however the operating gear for the shutting/ opening of the valve is placed outside as seen below. Sorry, the red segment should have been larger as the valve moves 90 degrees .The valve is shut having the waterpressure behind the valvedisc and the shaft for the shutting/opening is entering the pressure housing from fwd side whereas the grinding shaft is entering from the aft ( the square tip). A recess inside the housing allows for collecting drain and a drainpipe is connected to same.The housing is doublewalled being seawatercooled with crossover pipes passing flanges. I admit it is not easy to trace all the pipes I am still trying to figure out the details. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 07:24
Simon.
I am afraid we have to accommodate two more sets of rods for operating the mufflervalve, one for the shutting and one for the pneumatic grinderdrive. Having checked the limited drawings I have I would say the group exhausthousing is going through the pressure hull, which means no separate coolingpipe as far as I can see.I have tried to make a new rough sketch showing my idea of the muffler/ group exhaust valve arrangement, having omitted the coolingwater bridge pipes crossing the flanges. As you see the inside part of the group exhaustvalve and engine exhaustmanifold should be turned 90 degrees, sorry but I thougth this way of sketching wrongly shows more my ideas, so don`t get confused ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 07:39
Simon.
As to the driving gear for the two components I would assume the shutting/openingrods are placed at outboard side of the exhaustpipes and grinding gear rod inboard.
Note this is an assumption, as I have seen no drawings or pictures confirming this arrangement. :) 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 11:44
Tore, thanks for the new drawings! They are very useful and now I finally fully understand how the grinding works :) :)

I wondering if the "Brown" handal is the grinding handal for the muffler valve.
http://models.rokket.biz/index.php?topic=921.msg13393#msg13393 (http://models.rokket.biz/index.php?topic=921.msg13393#msg13393)

Also I was thinking there must be a third linkage as there still one Hull valve, sea water "Purple" that must drain the muffler somewhere ???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 12:05
Simon.
As to the driving gear for the two components I would assume the shutting/openingrods are placed at outboard side of the exhaustpipes and grinding gear rod inboard.
Note this is an assumption, as I have seen no drawings or pictures confirming this arrangement. :) 
Tore

Tore, here are the pressure hull openings.

I think:
(http://img707.imageshack.us/img707/3929/new1pa.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 12:25
Simon.
I do not think you have a handle for the grinding of the muffler valve as the rotation of the muffler valvedisc is done by the pneumatic motor operated by the LP airvalve in the engineroom, next to the airmotor. I cannot remember we had any drainvalve for the muffler, remember when surfacing the engines were started blowing the ballast tanks by exhaust, adjusting the backpressure by the mufflervalve, thus draining the muffler as well. We had always some water in the space between the mufflervalve and group exhastvalve but the water was generally collected in the drain chamber of the group exhaustvalve as shown on my sketch of same.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 12:44
Simon.
I do not think you have a handle for the grinding of the muffler valve as the rotation of the muffler valvedisc is done by the pneumatic motor operated by the LP airvalve in the engineroom, next to the airmotor. I cannot remember we had any drainvalve for the muffler, remember when surfacing the engines were started blowing the ballast tanks by exhaust, adjusting the backpressure by the mufflervalve, thus draining the muffler as well. We had always some water in the space between the mufflervalve and group exhastvalve but the water was generally collected in the drain chamber of the group exhaustvalve as shown on my sketch of same.
Tore

Yes, you are correct about the pneumatic motor.

So what is the "Brown" valve for? If you look hard you can see some marks next to the small arrow a "8" and "7" & "1".

(http://img802.imageshack.us/img802/7481/new4r.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 12:49
Tore, this is the "Purple" Hull valve, sea water. Do you think they have the wrong handle on this valve?

(http://img17.imageshack.us/img17/9611/new5ft.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 13:00
Simon.
I guess you have found reference to the pressurehull openings some where, for the fitting of the rods they are a bit awkward but as the rivets of the engineroom cover is preventing a better place this was the compromise. I based my assumption on the photo below. The shaft for the pneumatic motor enters the pressurehull aft of the shutting opening valverod. It is almost touching the athwart rivets of the engineroom cover and fairly close to the top centerline.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 13:06
Simon.
As to the driving gear for the two components I would assume the shutting/openingrods are placed at outboard side of the exhaustpipes and grinding gear rod inboard.
Note this is an assumption, as I have seen no drawings or pictures confirming this arrangement. :) 
Tore

Tore, here are the pressure hull openings.

I think:
  • Shutting/openingrods are placed is inboard side (Orange).
  • Grinding gear rod outboard (Brown).
  • (Purple) is the Hull valve, sea water.
(http://img707.imageshack.us/img707/3929/new1pa.jpg)


I was just about the say the same thing, but you must be a faster typer than me  ;D

Tore you are correct, shutting/openingrods is placed at outboard side of the exhaustpipes  (Orange) and grinding gear rod inboard (Red).
(http://img685.imageshack.us/img685/8169/new6nd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 13:32
Simon.
The brown handle is a puzzle to me. I think I remember vaguely we had some grease distribution boxes outside the pressurehull, it could be a selector handle for the greasing point with the numbers referring to the points but this would require a bit research before adding it to your drawing. The other  valve looks like an important sea valve but right now I have no suggestion, hopefully something pops up. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 13:55
Simon.
The brown handle is a puzzle to me. I think I remember vaguely we had some grease distribution boxes outside the pressurehull, it could be a selector handle for the greasing point with the numbers referring to the points but this would require a bit research before adding it to your drawing. The other  valve looks like an important sea valve but right now I have no suggestion, hopefully something pops up. ;D
Tore

I love your idea about grease distribution boxes, as it solution my other problem I was having with the number of openings :) :)

On page 30 of the Type VIIC Manual
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 13:58
Simon.
I do not think you have a handle for the grinding of the muffler valve as the rotation of the muffler valvedisc is done by the pneumatic motor operated by the LP airvalve in the engineroom, next to the airmotor. I cannot remember we had any drainvalve for the muffler, remember when surfacing the engines were started blowing the ballast tanks by exhaust, adjusting the backpressure by the mufflervalve, thus draining the muffler as well. We had always some water in the space between the mufflervalve and group exhastvalve but the water was generally collected in the drain chamber of the group exhaustvalve as shown on my sketch of same.
Tore

Yes, you are correct about the pneumatic motor.

So what is the "Brown" valve for? If you look hard you can see some marks next to the small arrow a "8" and "7" & "1".

(http://img802.imageshack.us/img802/7481/new4r.jpg)

Tore, I imagine the small pipe on the right of the valve would be the grease input line?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Feb , 2013, 14:18
Simon.
Yes, if you look at the aft engine bulkhead starboard side, just underneath the drainvalves from the starboard group exhaust valve you will find a round container having a pumphandle, see aft sideview yard drawing. This is the greasepress pump, it is a shot in the dark, but worth while checking.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 15:50
Tore, any idea what the grease distribution boxes would look like? Or how it may work?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Feb , 2013, 22:29
Tore, I have added the two new linkages, and updated the muffler :)

(http://img515.imageshack.us/img515/8363/new1l.jpg)
Fig. 1. New drawing

(http://img713.imageshack.us/img713/6039/new3d.jpg)
Fig. 2. Old drawing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2013, 00:04
Simon
Greasepump.
On starboard side aft engineroom bulkhead you see the greasepump as on the photo below. Marked on this picture you probably see the distribution cock, the namedisc and behind a steelblock which I assume is the distributionbox which I guess is outside the pressurehull  in the case of the handle you questioned. Again this is an assumption from my side. ;D 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2013, 00:20
Simon
Greasepump.
I guess the greasepump has not changed very much since the time of the VIICs. Below is a drawing of a to days execution, you shall find pneumatic driven  versions on the gas stations I believe. In the case of the VIICs it was operated by a handbar more or less as shown on the drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2013, 01:11
Simon.
Grease pump.
I was too quick marking the greasepump in my post above mixing up the drain cock with a grease cock :( . I got hold of a better picture of the pump as shown below, may be with your material you should be able to follow the greaselines to the cock? ;)  On this photo you a able to have another view of the group exhaustpipe valve draining as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Feb , 2013, 12:00
Hi Tore

I tried to track the grease line from the pump but could follow it fully as it went behind a larger pipe.

I did noted that there are two small pipes from the pump, I think sometime after 1943 they added a 2nd grease line to the pump. I follow both lines forward  to the pressure hull. One grease line goes  to the distribution box and the newer 2nd lines goes somewhere new. Below you can see the grease line and small tap.

(http://img690.imageshack.us/img690/1723/new1sc.jpg)
Fig. 1. The 2nd newer grease line.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Feb , 2013, 14:04
Tore, I have added the two new linkages, and updated the muffler :)

(http://img515.imageshack.us/img515/8363/new1l.jpg)
Fig. 1. New drawing

(http://img713.imageshack.us/img713/6039/new3d.jpg)
Fig. 2. Old drawing.

Top view

(http://img7.imageshack.us/img7/1710/new1rr.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2013, 14:38
Simon.
I have been looking into the grease distributor theory the whole day, and I can not see any other device which fit into this handle. My theory is as follows one of the pipes end up at the shutoff cock before entering the grease distribution system. The system has to be straight forward and simple. On my sketch below I am showing my idea.The handle spindle is bored allowing grease under pressure to enter a space made by a lantern space ring on both side of the packing,(purple) thus entering the hollow spindle through the pressurehull and into a rectangular distribution box on the outside of the pressure hull. In the distribution box is a circular disc having bore in connection with the hollow shaft. The disc circumference have shallow bores, except the bore to the shaft, corresponding to the outlets of the distributionbox and the bores contains a springloaded ball acting as a shutoffvalve for the outgoing pipes at the same time providing notches of the disc movement. The idea is to have full control of the supply to the selected greasepoint and that no leakages is entering any other pipes except the selected, thereby ensuring the selected greasepoint is lubricated.
This ended as a long story, may be the sketch is easier to understand.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Feb , 2013, 14:47
Simon.
I have been looking into the grease distributor theory the whole day, and I can not see any other device which fit into this handle. My theory is as follows one of the pipes end up at the shutoff cock before entering the grease distribution system. the system has to be straight forward and simple. On my sketch below I am showing.Thehandle spindle is bored allowing grease under pressure to enter a space made by a lantern space ring on both side of the packing,(purple) thus entering the hollow spindle through the pressurehull and into a rectangular distribution box on the outside. In the distribution box is a circular disc having bore in connection with the hollow shaft. The disc having shallow bores, except the bore to the shaft, corresponding to the outlets of the distributionbox and the bores contains a springloaded ball acting as a shutoffvalve for the outgoing pipes at the same time providing notches of the disc movement. The idea is to have full control of the supply to the selected greasepoint and that no leakages is entering any other pipes except the selected, thereby ensuring the selected greasepoint is lubricated.
this ended as a long story, may be the sketch is easier to understand.
Tore

Tore, this is great!!! The sketch is fantastic :) :)

I have a similar idea in my head but your sketch is far better!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Feb , 2013, 00:12
Grease Distributor and Lines

(http://img526.imageshack.us/img526/7409/new1mz.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Feb , 2013, 01:25
Simon.
Excellent, for some reason I have a picture in my head that the distribution boxes were rectangular, but circular is of course easier, so leave it at that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Feb , 2013, 02:03
Simon.
Excellent, for some reason I have a picture in my head that the distribution boxes were rectangular, but circular is of course easier, so leave it at that.
Tore

Tore, I went with a octagon ;)

(http://img560.imageshack.us/img560/999/new2ko.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Feb , 2013, 02:53
Simon.
Just as good, I based my assumption on the cheapest way of production.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 00:42
Simon.
The only item left on the valve question is the purple valve. There are two valves each symmetrically placed on port and starboard side. Both have a handle of the boardvalve seawatertype so I guess that`s correct. This rules out the  single drain of the supplyline to the seacompensating head tank in the conningtower. The valves are not shown on any systemdrawings available to me, thus systems before the schnorkel. My assumption would be this is a seawatervalve installed on the schnorkel boats. The schnorkel air inlet and exhaust outlet would not require two symmetrical placed seawater valves in this position. When schnorkeling the dieselengine  sea coolingwater has not been changed  and leaves overboard in the normal way, trapped air in the outboard seacooling watersystem  could cause problems. On the old systemsketches it is an outboard ventcock in the coolingwater space for both silencers marked "n" on plate 13 and pointing forward, this cock is not accessable during schnorkeling. May be the purple valve is a modification for the schnorkeling boats enabling venting while schnorkeling? Again this is only an assumption from me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Feb , 2013, 00:58
Tore, I have added the rare Style 6, Late war Diesel exhaust outlets1. There are no known drawings/plans and only five known photo's of this style. With this style the outlets are below the waterline. There is very little room between the pressure hull and casting (about 190 mm) so you can not run the exhaust pipe directly to the outlet. So I have added a box around the outlet to get the necessary volume. I also had to run the exhaust pipe between the pressure hull/casting/and high pressure bottles.
 
Tore, welcome any feedback on my engineering.

1. The Wolf Pack: A Collection Of U-Boat Modelling Articles by Dougie Martindale / Wink Gris
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Feb , 2013, 01:32
Simon.
The only item left on the valve question is the purple valve. There are two valves each symmetrically placed on port and starboard side. Both have a handle of the boardvalve seawatertype so I guess that`s correct. This rules out the  single drain of the supplyline to the seacompensating head tank in the conningtower. The valves are not shown on any systemdrawings available to me, thus systems before the schnorkel. My assumption would be this is a seawatervalve installed on the schnorkel boats. The schnorkel air inlet and exhaust outlet would not require two symmetrical placed seawater valves in this position. When schnorkeling the dieselengine  sea coolingwater has not been changed  and leaves overboard in the normal way, trapped air in the outboard seacooling watersystem  could cause problems. On the old systemsketches it is an outboard ventcock in the coolingwater space for both silencers marked "n" on plate 13 and pointing forward, this cock is not accessable during schnorkeling. May be the purple valve is a modification for the schnorkeling boats enabling venting while schnorkeling? Again this is only an assumption from me.
Tore

Tore, I am not sure also ???

I checked the few drawings I have of the schnorkel system, and I can not see any pipes that look like drains :(

I off to work tomorrow so I will check my other drawings in a few days.

Maciek, do you what these valves are for?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 01:36
Simon
I guess the box you designed has a duct going down below sealevel to the outlet thus act like the sparkarrestor which is the last item before the exhaust goes overboard, otherwise the outlet outside the casing looks very much like the U 995 design having outlet above the sealevel as shown on the drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Feb , 2013, 02:37
Simon
I guess the box you designed has a duct going down below sealevel to the outlet thus act like the sparkarrestor which is the last item before the exhaust goes overboard, otherwise the outlet outside the casing looks very much like the U 995 design having outlet above the sealevel as shown on the drawing below.
Tore

Tore, would you need a spark arrestor if the exhaust outlets are always underwater?

Here the side view. You can see the box that is between the casting and the pressure hull, and the exhaust pipe running around the high pressure bottle and down to the box. 

(http://img90.imageshack.us/img90/8944/new2tu.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 04:45
Simon.
I guess not if the outlet is submerged all the time. I would assume however that there would be a kind of sparkarrestor in the box indicated by you.
Below a photo showing the exhaustoutlet of the KNM Kaura at the handing over to the Germans as U 995 Oct 2. 1971.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 07:22
Simon.
I have to confess I didn`t like my yesterdays assumption of the purple valve very much. Having another look at the outboard coolingwater system it struck me the pipes as drawn on plate 13 allows full direct seaconnection to the system all the time. I do not remember the system of course, but no way you allow full seawater pressure to the inside of a submarine without a shut of valve (depthcharging- deepdiving etc.) My revised theory would be, the purple valve marked correctly as a board seawater valve  equipped as an important valve with a grease cup and a shut/open indicator could be the sea coolingwater shut off valve. The most likely place to install such a valve would be in the coolingwater bend crossing the flange of the group exhaustvalve to the mufflervalve housing. This is pretty close to the drawn purple valve. Below is my sketch showing the assumed valve. Repeating my shelf, this is an assumption. The drawback of the theory is  that the germans have omitted this essential valve on all the systemsketches, that is hardly to believe. ;) Open for any other ideas but the system has to be capable of being shut of from the sea. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 25 Feb , 2013, 08:19
Hmm... I agree with Tore in that there would not be a direct sea connection without a shutoff valve... too risky. Is it a question of faulty recording? Is it a change put in after the manuals were produced? or, perhaps a post war change? Perhaps the owners of poor U-995 thought it a useful thing to try, but one not on the orig German manuals? Was the change tried as the war was winding down and people thought it not worth recording at that point? These observations bring up so many exciting questions, don't they! B-)
Christopher... hanging on the edge with curiosity...




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 08:46
When the map doesn`t match with the terrain it is usually  an advantage to follow the terrain. In this case we have definitely two objects being genuine seaboardvalves having a construction of  important valves, I cannot imaging any other purpose for these valve at that place. On the other hand the German "grundlichgkeit" makes it difficult to understand why these important valves are not shown on any drawings showing the MAN or GW systems way back in time, after all this is not a late war thing, but basic submarine design. It puzzles me, may be I have overlooked something, am I getting too old? ??? .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 25 Feb , 2013, 09:56
When the map doesn`t match with the terrain it is usually  an advantage to follow the terrain. In this case we have definitely two objects being genuine seaboardvalves having a construction of  important valves, I cannot imaging any other purpose for these valve at that place. On the other hand the German "grundlichgkeit" makes it difficult to understand why these important valves are not shown on any drawings showing the MAN or GW systems way back in time, after all this is not a late war thing, but basic submarine design. It puzzles me, may be I have overlooked something, am I getting too old? ??? .
Tore



Perhaps there is a drawing map to lead us back to the path... but there are those of us who enjoy thinking beyond a drawn black and white image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 10:27
True Christopher, hopefully we find the path. So I keep looking and pondering hoping to find the correct input  for the magnificent artwork Simon as well as you makes.
Usually we end up pretty close to the real thing, at the  same time it is fun though.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Feb , 2013, 11:32
Simon.
I guess not if the outlet is submerged all the time. I would assume however that there would be a kind of sparkarrestor in the box indicated by you.
Below a photo showing the exhaustoutlet of the KNM Kaura at the handing over to the Germans as U 995 Oct 2. 1971.
Tore

Tore, I was thinking how hot would the exhaust gases be when it reached the outlet?
 
Would it be a bad thing to have hot exhaust gases hearting up the pressure hull, in a small area?

Tore, not sure if you seen Style 6 of the exhaust outlets before, so here a few photo's and drawings.
(http://i212.photobucket.com/albums/cc118/dougie47/U421_left_6aug44_toulon.jpg)
(http://i212.photobucket.com/albums/cc118/dougie47/U421_left.jpg)
(http://img25.imageshack.us/img25/3240/u642toulonle11dc1945.jpg)

(http://img30.imageshack.us/img30/5931/typevii41view3.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 11:43
Simon.
As far as I can see the style 6 exhaust outlet is submerged in the area where you have a possible contact with the pressure hull, moreover the exhaustgases are considerably cooled  at the outlet. I don`t believe you would have a problem.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Feb , 2013, 11:52
Simon.
I have to confess I didn`t like my yesterdays assumption of the purple valve very much. Having another look at the outboard coolingwater system it struck me the pipes as drawn on plate 13 allows full direct seaconnection to the system all the time. I do not remember the system of course, but no way you allow full seawater pressure to the inside of a submarine without a shut of valve (depthcharging- deepdiving etc.) My revised theory would be, the purple valve marked correctly as a board seawater valve  equipped as an important valve with a grease cup and a shut/open indicator could be the sea coolingwater shut off valve. The most likely place to install such a valve would be in the coolingwater bend crossing the flange of the group exhaustvalve to the mufflervalve housing. This is pretty close to the drawn purple valve. Below is my sketch showing the assumed valve. Repeating my shelf, this is an assumption. The drawback of the theory is  that the germans have omitted this essential valve on all the systemsketches, that is hardly to believe. ;) Open for any other ideas but the system has to be capable of being shut of from the sea. ;D
Tore

I have not seen a valve with this style of open/shut indicator before on the Type VIIC, perhaps it could be evidence that it was not added by the Germans or very very late into the war (in Norway) ???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Feb , 2013, 13:24
Simon.
I believe it is a original German valve, if you look I guess you shall find more valves with an indicator, not always identical to this one, some have a threaded ring with a tap in a  pedestal slot travelling on a threaded part of the valve spindle, others have a double pointer fixed to the valve spindle, the latter you can  find as a hull fuelvalve just above the IMO motor for the fwd periscope hoist on the port side of the fwd controlroom.
The main problem is that on the systemsketches we have seen you have full seapressure directly to the seawater coolingsystem without a shut off valve for diving.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Feb , 2013, 13:52
Simon.
The mysterious purple valve.
Finally I believe we have found an explanation which hold water ;D . The fuel/ballast tanks no 2 port and starboard have a residual venting. The venting of the fuel/ballast tanks are usually operated from the controlroom. In the fuel mode the ballasttanks 2 and 4 port and starboard are separated by gatevalves operated from deck. However the venting ducts have an emergency shut valve Right at the merger of the ventduct and the saddletank. The philosophy is that in case of damage to the ventingducts you should shut the the emergency vent valves to save the buoyancy of the saddletanks. The same philosophy must be valid for the residue venting as well, but I have found no mentioning in the literature of these emergency valves in the aft part of fuel/ ballast tanks 2 port and starboard. My conclusion is nevertheless: the purple elaborate and important valves are the emergency shut off valves for the residual venting duct of the fuel/ballasttanks 2 port and starboard. As a proof I show a picture of the emergency shut of valves for ballast/fuel tanks 4 port and starboard operated from the controlroom, as you see they are identical only the handle is removed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Feb , 2013, 01:22
(http://img803.imageshack.us/img803/4140/new1p.jpg)
Fig. 1. Pressure hull openings.

(http://img515.imageshack.us/img515/8313/new2g.jpg)
Fig. 2. New exhaust system.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2013, 02:08
Simon.
You have probably seen it, but anyhow below is the drawing of the emergency ventvalve fitted directly on the ballast saddletank. The intricate coolingpipe arrangement for the group exhaust valves follows this evening my time, I believe the explanation and solution of the cooling water shut of valve has been found just minor details remains.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Feb , 2013, 02:15
Hi Tore,


The fuel/ballast tanks no 2 port and starboard have a residual venting. The venting of the fuel/ballast tanks are usually operated from the controlroom. In the fuel mode the ballasttanks 2 and 4 port and starboard are separated by gatevalves operated from deck. However the venting ducts have an emergency shut valve Right at the merger of the ventduct and the saddletank. The philosophy is that in case of damage to the ventingducts you should shut the the emergency vent valves to save the buoyancy of the saddletanks. The same philosophy must be valid for the residue venting as well, but I have found no mentioning in the literature of these emergency valves in the aft part of fuel/ ballast tanks 2 port and starboard. My conclusion is nevertheless: the purple elaborate and important valves are the emergency shut off valves for the residual venting duct of the fuel/ballasttanks 2 port and starboard. As a proof I show a picture of the emergency shut of valves for ballast/fuel tanks 4 port and starboard operated from the controlroom, as you see they are identical only the handle is removed.


I like your explanation very much. Here is another photo of the emergency vent of the Tauchbunker 4:

(http://imageshack.us/a/img32/5042/tb4notentluftungventil.png)

What wonders me, is that on the "vent diagram" (http://uboatarchive.net/U-570Plate16.htm (http://uboatarchive.net/U-570Plate16.htm)) the residual air vent duct has no emergency vents. Also, in the description of the Tauchanlagethere is said:

Quote
An den Austritten der Entl
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2013, 04:40
Maciek.
I agree with you, the gate valve is probably fairly close to the ballasttank anyhow. As you have evidence in the original Tauchanlage text I believe we now finally have come to the final correct arrangement. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2013, 08:32
Simon.
The last and may be most complex item on this topic is probably the group exhaust coolingwater piping. The system sketches gives the impression that the internal coolingwater system is subjected to full seawaterpressure which is an impossibility. Based upon limited available sketches and photos I have have made the following proposal: It is a shut of seavalve fitted on the group exhaust valve housing at the side of the double walled drainspace. On the u historia photo of the group exhaust valve,  it is the biggest valve having pipeconnection marked 6. The double walled cast steel group exhaust valvehousing  can for sure  take the max seawaterpressure. All the other items in the internal coolingwater system you want to have behind this shut off valve. The more flanges packings and stuffingboxes which are subjected to exessive pressure the more risk you have for serious or even fatal leakages. The  valve housing consist of 3 parts, the main housing, the endcover and an exhaust manifold transmissionflange. The latter two have to be cooled as well and as they should be behind the main seavalve, it would require some unusual pipings. On the sketch below you see my proposal, the only pipe I have not been able to get confirmed is the top pipebend for the coolingwater from the exhaust manifold to the transmission flange.
As so many times before the real execution deviates a bit from the systems sketches, they just show the principle, not the execution. I have to finish off with my reservation: this is a proposal. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Feb , 2013, 15:30
Simon.
The last and may be most complex item on this topic is probably the group exhaust coolingwater piping. The system sketches gives the impression that the internal coolingwater system is subjected to full seawaterpressure which is an impossibility. Based upon limited available sketches and photos I have have made the following proposal: It is a shut of seavalve fitted on the group exhaust valve housing at the side of the double walled drainspace. On the u historia photo of the group exhaust valve,  it is the biggest valve having pipeconnection marked 6. The double walled cast steel group exhaust valvehousing  can for sure  take the max seawaterpressure. All the other items in the internal coolingwater system you want to have behind this shut off valve. The more flanges packings and stuffingboxes which are subjected to exessive pressure the more risk you have for serious or even fatal leakages. The  valve housing consist of 3 parts, the main housing, the endcover and an exhaust manifold transmissionflange. The latter two have to be cooled as well and as they should be behind the main seavalve, it would require some unusual pipings. On the sketch below you see my proposal, the only pipe I have not been able to get confirmed is the top pipebend for the coolingwater from the exhaust manifold to the transmission flange.
As so many times before the real execution deviates a bit from the systems sketches, they just show the principle, not the execution. I have to finish off with my reservation: this is a proposal. ;D
Tore

Q. Tore, From your group exhaust coolingpipes a.jpg (http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=3603) drawing you have drain line (Red) inboard and the crossover line (Orange) outboard (Top Drawing). This were a reason why have done it this way? As I would had imagine it was the other way, with the crossover line inboard and the drain outboard, as would used the minimum amount of pipe (Bottom Drawing).

(http://img577.imageshack.us/img577/5356/graphic1xv.jpg)
Fig. 1. Cross-section with pipe layout.

(http://img24.imageshack.us/img24/562/exhaustmanifold10.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Feb , 2013, 16:04
'T' handles hatches within the floor plating

(http://imageshack.us/a/img341/7719/new3p.jpg)

(http://imageshack.us/a/img829/307/new4be.jpg)

Tore, look what I found today, you can see the handle :D

(http://i1137.photobucket.com/albums/n511/U796/U-166-Lecompartimentmachine.jpg)
U-166 (http://www.mille-sabords.com/forum/index.php?showtopic=40300&st=175 (http://www.mille-sabords.com/forum/index.php?showtopic=40300&st=175))
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Feb , 2013, 16:52
Tore, slowly checking and updating the piping (colours piping).

(http://imageshack.us/a/img843/2562/new2it.jpg)

(http://imageshack.us/a/img707/9535/new3iu.jpg)

(http://imageshack.us/a/img43/6697/new4jp.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Feb , 2013, 00:17
Simon
Coolingwater group exhaust valve drain.
If you look right down at the side of the E-room door I believe you find a drain collecting funnel for the drainpipes that`s why I put the drain inboards.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Feb , 2013, 00:21
Simaon.
T handles.
Very good, you realize of course the engines are not GWs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Feb , 2013, 07:19
Simon.
Group exhaustvalve housing.
Very good you made a drawing of this item. If you check the u historia photo I believe you shall see the transferflange from the exhaustmanifold, having a smaller diameter than the inlet to the housing. A transfer piece consisting of two flanges having different diameter and a cooling waterspace in between is causing the complication. I have taken the liberty to mess up your nice drawing in order to explain what I mean. see the drawings below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2013, 08:14
Simon.
Group exhaustvalves.
Having received further pictures I have to revise my last theory slightly. The revised system drawing is shown below. I guess there is a small detail which may be a bit unclear, I don`t believe there is a connection at the crossing point, engine coolingwater pipe and the pipe to the drain- crossover selector cock. In fact on the photo the pipe is not shown, I am sure it is there but as a separate pipe going somewhere else. Otherwise I hope the sketch is self explaining.
I have again messed up your nice drawing in an attempt to show the complete arrangement. Most of the changes are based on photos and drawings. Otherwise the system is following basic requirements like keeping pipes, flanges, packing and stuffingboxes which are not pressureproof behind the main overboard seavalve. Further the coolingwater should go from low inlet to high outlet. The main coolingwater outlet from the engine is shown being a fairly large pipe, the full amount of coolingwater can not flow through the narrow coolingspaces of the transmission flange and end cover. They are cooled in series and the pipes are much smaller as shown, howewer the only connection not confirmed by documents is  the small pipe branch off from the main cooling waterpipe ( or exhaustmanifold) to the transmission flange. I have indicated two possibilities on the drawing. The system is elaborate and many pipes are stacked on top and behind each other, this is not easy to draw. The collection of valve and pipeoutlets, drains and vents is really cramped in the aft bulkheadarea  and would require another study I guess. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 02 Mar , 2013, 08:50
I am just blown away by the technical knowledge of the contributers on this forum.
I bet with everyones combined knowledge here we could actually build a real U-boat!
All we would need is a wealthy, slightly off,  financier like the gentleman building Titanic II, and lots of young muscle ;)

Seriously though, just amazed by the information and knowledge contributed on this forum.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 02 Mar , 2013, 09:09
I am just blown away by the technical knowledge of the contributers on this forum.
I bet with everyones combined knowledge here we could actually build a real U-boat!
All we would need is a wealthy, slightly off,  financier like the gentleman building Titanic II, and lots of young muscle ;)

Seriously though, just amazed by the information and knowledge contributed on this forum.

OldNoob,
I am not only blown away by the assembled  tech knowledge, but by the forensic  extrapolation we have been able to do with a truly limited set of input. There are only so many plans, so many period photos, only so many boats, and 1 Pajama-wearing Tore!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Mar , 2013, 09:38
Hi guys.
I have been through this before, graduating 60 years back as lieutenant (E) on Royal Navy's engineering training course on A,F, S and U classes of submarines in UK, coming home realizing I got a VIIC 41 totally different, with no contact with the germans and practically no drawings. One advantage to present days though, you was on board and could crawl,follow pipes and look at the items. Howewer the testing that your assumptions was right or wrong was slightly more exciting than experiencing the evaluation of my present days assumptions on this thread today. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Mar , 2013, 23:40
Tore, here the remaining of the engine exhaust, how does it look?

(http://img33.imageshack.us/img33/9933/new1qzy.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2013, 01:56
Simon.
Looks fine. May be it is time to put in some spice in in the spaghetti. You love for details require venting of the exhaust manifold cooling bends,foldable handle for the starting air handwheel and the manometer for the supercharger pressure. Sorry for my bungling on your nice drawing. ;)

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2013, 02:54
Off the topic.
Surfacing.
I have mentioned before the normal way of surfacing, nicely take the boat up by hydroplanes to periscope depth, the quick sweep with the periscope before blowing all the ballasttanks until semisurfaced in a horizontal position and then blowing the tanks by diesel engine exhaust or in case of RN U class submarine by electric blower.
It happens howewer you have to make emergency surfacing, blowing you ballasttanks at great depth with an incredible amount of HP air. Then you accelerate towards the surface and in case of using the hydroplanes and E-motors as well you might end up braking the surface like the picture below, which I found in one of my Norwegian submarine pamphlets. The picture is presumably taken of a Norwegian U class surfacing in a Norwegian fjord. I guess more for show off rather than necessity. I guess the surfacing angle would be close to 45 degrees exceeding the spilloff limit for the battery acid , spectacular but not to be recommended. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Mar , 2013, 00:52
Tore, a few more pipes...

(http://imageshack.us/a/img541/1539/new1k.jpg)

(http://imageshack.us/a/img339/6687/engineroom4.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2013, 12:43
Simon.
I am back with a few remarks tomorrow as I am checking a few pipedetails which seems to take more time than I anticipated. It is primarily the connection to the transmissionflange cooling which needs some attention.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Mar , 2013, 12:59
No worrys, I am off to the big city today to do some shopping, so no u-boat drawing today.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Mar , 2013, 13:06
Tore, one thing, how did the cooling water get outside the pressure hull through the hull flange?

If you were looking into the flange at the top, would you see the inner collar for the cooling water, if so how wide is it?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2013, 13:39
Simon
The group exhausthousing don`t have a flange going through the coolingspace, it is simply a ringflange intergrated with the outer surface of the housing without obstructing the cooling waterflow out of the pressurehull. You want see the coolingwater space at all it is entirely closed like a cooling waterspace for a cast iron car engineblock.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2013, 13:52
Simon
I guess you see the transmissionring small flange at the exhaust manifold side on the shipyard drawing top view and the groupexhaust housing on the sideview the difference between the two migth give you an estimate for the coolingwater dimension.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Mar , 2013, 14:00
Something like this?

(http://img818.imageshack.us/img818/2320/new1asy.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2013, 14:02
Simon
Yes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2013, 14:21
Simon.
It got to be only one flange in contact with the pressure hull and it looks like the flange is fixed from the inside, the housing is then free to (heat) expand outwards.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2013, 08:58
Simon.
Group exhaust valve coolingwater pipes.
To make an understandable drawing of this system is not easy, so when keeping an eye on the confusing drawing below I`ll try to give an explanation:
making use of the systemdrawing and copy the system would not work so basis for the described system is photos and common engineering sense.
The main coolingwater outlet from the dieselengine is close to where the manifold endflange joins the transition piece flange. The pipe goes down to the main coolingwater valve at the aft bulkhead, to the short pipe between the main cooling watervalve and the main seavalve and then via the main seavalve to the group exhaust valve and  overboard.
Immediately after the exhaust manifold it is a small pipe branch off which take some of the coolingwater to the lower part of the transition flange, the water leaves the same flange at the outlet on the top. Then the water goes to the lower inlet of the endflange and leaves same at the outlet on the top. It goes down and join the short pipe between the main coolingwater valve and the main sea ( overboard) valve. On the short pipe between the two mainvalves is a branch off to a two way cock, this cock can be put in drain position leading  the system to a funnel and bilge or to the other position connecting the system the the other engine system.
The main drain pipe (yellow)and valve is obvious and ends together with other drains in a funnel to the bilge.
Allthough not shown on one of the engines, there should be a manometer connection to the main drain of the group exhaust valve, that drain comes from the space between the group exhaustvalve and mufflervalve which might have a severe leakage and full seapressure in the space.
The system is based on interpretation of photos and some basic musts but in the end an assumption from me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Mar , 2013, 00:39
Tore, a few more pipes and tweaking of alignments :)

(http://img690.imageshack.us/img690/9444/new1ro.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2013, 08:27
Simon.
It is beginning to look like the real thing.
I am a bit in doubt of the location of the valve and pipe assembly at the aft bulkhead. I know you recently relocated the supercharger. With a less professional way I used that as a reference. On the shipyard drawing topview it looks like the centerline of the main coolingwater outlet matches the centerline of the outboard supercharger shaft. On your drawing the centerline of the pipe is a bit offset to the inboard. I again bungled with you drawing and put the coolingwater outlet as on the shipyard drawing see drawing below. With reference to the photos I placed the main cooling water pipe  straight down to the main coolingwater valve realizing it created some distance to the  valve inboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2013, 23:51
Simon.
The coolingwater branch off.
My assumption is founded on the photo below and the orthodox way of cooling waterflow, in at the lowest point out at the highest
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Mar , 2013, 01:07
Simon.
Further to my previous post I show below my basis for the assumption of the pipearrangement for the transition piece and main drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Mar , 2013, 00:15
Tore, a few more pipes and tweaking of alignments :)

(http://img341.imageshack.us/img341/839/new1zd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2013, 08:35
Simon.
Slowly but steady approaching the complete arrangement. ;D  I noticed the  frames at the group exhaustvalve hull outlet have a larger distance to accommodate a large flange and that the hullpassage is a bit different from what assumed. I shall try to figure out further details. Below I have tried to indicate the coolingwater pipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Mar , 2013, 21:07
Simon.
Slowly but steady approaching the complete arrangement. ;D  I noticed the  frames at the group exhaustvalve hull outlet have a larger distance to accommodate a large flange and that the hullpassage is a bit different from what assumed. I shall try to figure out further details. Below I have tried to indicate the coolingwater pipes.
Tore

Tore, I can not understand the two new pipes you have added to my drawing :(

Are you jointing the new Main cooling water outlet exhaust manifold  pipe to a exiting pipe (Red; This pipe is between the transfer flange and manifold)?

(http://img15.imageshack.us/img15/6387/new1ov.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Mar , 2013, 00:08
A small update today.

(http://img831.imageshack.us/img831/5844/new1rr.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2013, 01:57
Simon.
I am the first to admit it is not easy to sort out these pipes. ;)  I have made a drawing trying to explain my assumption below. The drawing shows the port engine in order to make it easier to check with the u historia photo.
I guess it is bit easier when you add the larger flange of the transition piece towards the group exhaustvalve housing ( red dotted oval). The largest red circles indicate the pressurehull flange for the hull outlet on top of the group exhaustvalve.
From the exhaust manifold main cooling waterbend out  you have a branch off (1) purple pipe going to the inlet at the bottom of the transition piece( 2). Out of the transition piece at the top (3.) From (3 )green pipe goes to the bottom of the endpiece( 4) and out at the top (5). The pipe now light blue goes down to the pipe between the main coolingwater valve and the main overboard valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2013, 05:53
Simon.
Further to my above post. To have a better understanding, remember the basic for coolingwater flow : inlet at the bottom and outlet at the top. On the photo below I have indicated the branch off from main coolingwater pipebend to inlet transition piece ( purple pipe).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Mar , 2013, 19:25
Tore, thanks for the photo & drawings.

How does this look?

(http://imageshack.us/a/img189/1267/new2cs.jpg)

(http://imageshack.us/a/img690/7069/new3cr.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2013, 22:59
Simon.
This make sense to me! ;D  How about adding the other flange of the transitionpiece?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2013, 23:33
Simon.
Transition piece.
Just indicating the two flanges of the transition piece which I guess is necessary to locate the coolingwater outlet.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Mar , 2013, 00:00
I feel that because of the shape of the group exhaust valve casting you would see the other flange. From the photo, you can see that the nuts are under and inward of the casting.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2013, 01:50
Simon.
I see. You know for sure much more about this than I do.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2013, 09:26
Simon.
The group exhaust valve finishing touch. ;D
Below is my assumption of the hullpassage for the group exhaustvalve. No doubt the outlet is flanged to the inner pressurehull and nuts are locked by lockingplates,see photo below. The only place the pipebend can bypass the external exhaust pipeflange is outboard as indicated on the sketch. For the crossing of the next next flange ( mufflervalve,) the bend leaves the exhaustpipe on the top and goes to the bottom inboard of the mufflevalve housing. Further in the same way for the other flanges.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 10:49
(http://imageshack.us/a/img43/9681/new2cq.jpg)

(http://imageshack.us/a/img189/143/new1ay.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 10:54
Tore, the drain line with the sight glass. Are we missing it or is it not on U-995?

http://www.uboatarchive.net/U-570Plate13.htm (http://www.uboatarchive.net/U-570Plate13.htm)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 12 Mar , 2013, 10:56
Nice work Simon - as always! I like the pressure gauge. As an artist, I salute your bravery for taking on such a complicated piece!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 11:01
Tore, in the photo "Exhaust Manifold.JPG" what is the single pressure gauge for? Should there be two of them?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 11:12
Tore, bottom left of this photo look like the Thereometer that this found near the bend, do you think it just fixed to the main exhuest pipe?

http://www.uboatarchive.net/U-570Plate13.htm (http://www.uboatarchive.net/U-570Plate13.htm)

(http://img827.imageshack.us/img827/1130/p1100215y.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 11:13
Simon.
You have even introduced the grease connections on the group exhaust valve. I assume the pipes goes to a distributionpoint which is fed by the greasepump on the aft bulkhead. The manometer is of course mandatory on this point. Good work!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 11:32
Simon.
Sight glasses.
We have indeed not installed the sigth glasses. I have not been able to locate the glasses and presume they are there but further down near the funnel. This is the last check on the coolingwater before leaving the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 11:36
Simon.
Thermometer.
 I think it is, good spotting!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 11:59
Simon
I have tried to find the photo Exhaustmanifold jpg. but in vain. Seems to be too many photos and no system could you just show it?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 12:56
Simon
I have tried to find the photo Exhaustmanifold jpg. but in vain. Seems to be too many photos and no system could you just show it?
Tore


(http://img856.imageshack.us/img856/650/new1gn.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 13:07
Simon.
Manometer-
Thanks. I don`t believe this has anything to do with the exhaustmanifold. The manometer is marked at 12 atu which is the normal working pressure for the LP air supply. I
would assume it is the supply air for the main engine clutches.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 13:19
Simon.
You have even introduced the grease connections on the group exhaust valve. I assume the pipes goes to a distributionpoint which is fed by the greasepump on the aft bulkhead. The manometer is of course mandatory on this point. Good work!
Tore

Starting to add this system, but it hard as there areas of it that are missing in photo's  :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Mar , 2013, 13:21
Simon.
Manometer-
Thanks. I don`t believe this has anything to do with the exhaustmanifold. The manometer is marked at 12 atu which is the normal working pressure for the LP air supply. I
would assume it is the supply air for the main engine clutches.
Tore

Main engine clutches.

Next on the long list, likely to start this in about two weeks  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2013, 13:48
Simon
Main engine clutches.
I don`t believe the clutches are going to cause to much problem, I guess you are only to draw the visible parts. I `ll put up a  sketch showing how the system works for a better understanding as it makes it easier to draw.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2013, 01:14
Simon.
Greaselines.
I agree the greaselines are not easy to follow. I don`t believe the pipes are fitted in a very strict pattern and  you would probably find variation from boat to boat,so I would suggest you put the pipes where it is natural to allocate same,, and start with the known points. I believe there are two pipes out of the pump , I assume they are the port and starboard supply pipes as you have only one grease pump in this area. For each side, somewhere between the pump and the external selector valve you should have a distributor block, normally just a block without a selector, from this block you have one pipe to the external distributor and two pipes to the group exhaustvalve. I believe the rest of the grease points have greasecups like the residue ballast vent.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2013, 02:26
Simon.
I have to correct my last post :( , the group exhaustvalves have  locally placed greasecups with a distributor as can be seen on the u historia photo. I guess this makes life a bit easier as the two outgoing pipes would then be to port and starboard outboard grease selector. Thus all the internal grease points in this area have greasecups and distributors locally placed like the residue venting valves. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2013, 07:56
Simon.
Engine clutches.
Allthough you are planning to start with the clutches in about two weeks time I shall give a short description of the system.
 The clutch is a double cone frictionclutch operated pneumatic/hydraulic by linkages. Air of 12 atu comes from two small flasks ( not identified by me) to a distribution cock (red handle on the aft bulkhead) which direct two air pipes (in and out) to a hydraulic cylinder fixed to the aft bulkhead. The actuating piston in the cylinder has a pistonrod with bore connected to the actuating lever (yellow). This lever is has a "hinge" in the bilge and engages half way down to a shaftsleeve (light green) by a wheel. Moving the actuating lever back and forth slides the shaftsleeve which is connected to the inner linkage of the clutch and connect and disconnect the friction cones. The linkages consist of a crankbell lever which snap the cones in a locked in position. On the u historia photo you see the wormrod and the pistonrod fixed to a yoke having two guide rods. At the ends of the guiderods are some peculiar "nuts". These are spring loaded endstoppers which when the linkage snaps in position pushes the actuating lever a fraction back to release the engagement at the shaft slide to prevent a possible hotrunning. The clutch can be operated by a handwheel for emergency. Turning the handwheel turns the wormshaft (red)  which moves the (nut,pink) inside the the pistonrod. The nut moves in a slot to allow free movement of the pistonrod under normal circumstances, in emergency the "nut"engage the ends of the slot and moves the rod in and out.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2013, 10:15
Simon.
Engine clutches.
I just realized I forgot to put in my usual reservation: the above is my assumption . I migth add that the hydraulic air piston system is a bit uncertain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2013, 02:29
Simon
Pneumatic/hydraulic clutch system.
It might be I am mixing up with systems on other subs, but I base my assumption on that the pipes in and out of the operating cylinder are bigger than that of the airpipes to and from the operating handle. It looks as the pipes of the operating cylinder are going down whereas the air pipes are going up, a bit confusing .
The usual arrangement for this system has a floating corkplate as a barrier between the air and the oil ind the actuating cylinder. See sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2013, 02:55
Simon.
Checking the u historia photo of the starboard clutch I believe I found one of the small air/ oil flasks for the actuating piston. Way under the propellorshaft you can see the top of the flask and the two pipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2013, 07:53
Simon
The sketch showing the working of the pneumatic/hydraulic piston rod and the handoperated wormrod was not very clear as the  wormrod end was too short and the slot too long so here is a correction. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 14 Mar , 2013, 14:17
Simon and Tore -
I do not know if you have seen this wreck-dive video of U-251 at http://www.youtube.com/watch?v=Gw3EsX5bh4g (http://www.youtube.com/watch?v=Gw3EsX5bh4g)
The dive footage shows extensive damage but there are sections where the divers are over the aft casement. Surprisingly, there is a lot of detail of the exhaust sections  between the casement and pressure hull, as well as air induction that you can pick out. B-)
Especially around 6:30+  ;D
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2013, 15:27
Christopher
Fantastic .I`ll certainly scrutinise the details tommorrow. Thanks a lot.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2013, 02:03
Exhaustpipe expansion.
I had another look at the divingvideo of U-251 provided by Christopher and located the exhaust pipes outside the pressurehull. What strikes me is the relatively complex arrangement of connections  between the group exhaust valve, 90 degrees bend, muffler and sparkarrestor, all connections have a short visible part of an uncooled smaller pipe entering the next component.
This is not without any reason. As I briefly mentioned before, free heat expansion has to be provided for and the connections have an  flange for a "stuffingbox" allowing the pipe to expand freely into the next component. This uncooled exhaustpipe stub has a small diameter (no coolingjacket) which makes it is easier to provide such an expansion stuffing box . I guess you find the same arrangement for the exhaustmanifold.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2013, 02:36
Diving video U-251.
Having been a hobby moviemaker of diving videos I appreciate a good shot like the above movie. It is astonishing how some submarine wrecks  rest nicely at the seabottom.
We lost one of our U class submarines with all hands, just outside the Norwegian  coast in a German minefield February 1943. In 1985 the wreck was discovered and below is a photo of same resting almost like a display. The wreck is of course a wargrave, forbidden to be explored by divers.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 15 Mar , 2013, 12:55
Tore -
Do you know if there are surviving records of the operational/refit history of the KNM Kaura when she was with Norwegian Navy? Where might one go to request such things, and do you think that those with such records might be forthcoming to information requests?
What base did you operate primarily from? Would her Home Port possibly have records?

I, for one, would be willing to sift through such records if it could provide us with insights to her.
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2013, 16:05
Christopher.
I don`t believe there are any such records available. I have German records of U 995 from the war time. Her Norwegian time as a "front" submarine was fairly short I guess  some 4-5 years, I was on board half the time. She had a retrofit every 3 years. For the last years she was acting like a school sub.
We operated out of the submarine base in Trondheim Norway as from just after the war. The Germans  build two large submarinepens in Trondheim of which we used one. In March 1954 we moved to the a temporary submarine base in Bergen using an ex. US workshop and depotship as quarter till a new main permanent submarinebase was built near Bergen and ready February 1960.  The old submarines like KNM Kaura  U 995  were scrapped in the beginning of 1960 as 15 new submarines were built and put into service as from early 1960 till 1967 of course these submarines are all scrapped as well and replaced by new ones. I believe some records could be found at the main submarine base Haakonsvern in Bergen otherwise  The Norwegian Naval Museum , Horten, Norway might have some records how willing they are to give away records I have no idea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 15 Mar , 2013, 16:26
Thanks Tore -
I will see what, if anything, I can find out. Of course, since you and Simon have The engine room covered - I am focusing on the bow. The more I look, the more I see differences from other boats that would be interesting to track.
I know boats like that are a symphony of change - so we keep digging!
Have a good weekend!
Christopher

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2013, 01:31
Christopher.
You are right about there are differences between the boats even having the same buildingyears. When I got another boat, KNM Kya ex U 926 in 1954 I noticed quite a difference allthough the basic was of course the same. The boats were built at a different yards which apparently had different solution to many details. The most visible difference was probably U 926 had the new type of compasshousing whereas U 995 had the old streamlined. When you go into details as you and Simon, you are bound to find discrepancies between the boats. Below you are photos of KNM Kaura and KNM Kya showing the differences. In addition to the compass housing deviations they had 2 and 3 deck containers respectively and different schnorkel locking pin. For some reason the German fitted  Laboe U 995 with the new type of compasshousing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2013, 02:40
Simon
Pneumatic/ hydraulic clutch system.
When checking the u historia photo of the dirtyoil handpump on port aft engineroom bulkhead evidence is found that the airsupply to the clutch switching handle is coming from the top and the pipes out to the flasks are going down somewhere to the bilge thus the confusing photo from the starbord side is cleared up. I believe we can assume it is a pneumatic /hydraulic switching system with airpipes going down to the small flasks below the propeller shaft and oil supply/return  via sligthly larger pipes to the actuating cylinder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2013, 03:02
Simon.
Operating handle for clutches.
The operating handles for the clutches, painted red on U 995 are of the standard type sliding handle connected to a plug which fit into a slot locking the handle and cock in position. On the nameplate I have been able to decipher some of the text inboard reading EINR..... the rest is unclear to me, but I guess moving the handle inboard is clutching in.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2013, 03:34
Simon.
Clutch handle.
Knowing your liking for details, I show you the locking of the clutchhandle as fitted on U 995. On the port engine the nameplate is gone and the handle is loose and placed upside down, by that displaying the plug which fit into the namedisc shown on starboard engine. The handle is springloaded and you raise the sliding handle by having your thumb on the protruding nob. Just a minor detail for your pleasure ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Mar , 2013, 22:52
Added the deck plating today :)

(http://imageshack.us/a/img109/6687/engineroom4.jpg)

(http://imageshack.us/a/img29/8351/new1sb.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 01:40
Simon.
Too bad to cover up all the hard work you had with the piping ;D . Just a small detail, if you look at the u historia photo of the reserve luboil/fueltransfer pump forward port
side you`ll see the deckplates don`t have the red marked plate below. I know your lay out is according to some drawings, but the original luboil-and coolingwater pipes does not allow for this plate on poor old U 995. It could of course be one of these deviations previously mentioned.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 07:15
Simon.
Deckplates.
I checked a photo I had of the plates of u 995 presumeably from 1965- 70 so most probably in the original execution. An accurate position of the deck operated valves are hard to established, but a  view of the diamond shaped pattern is quite clear. Another detail is the step down which seems to be aft of the vibration damper.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 13:04
Simon.
Deckplates.
I checked a photo I had of the plates of u 995 presumeably from 1965- 70 so most probably in the original execution. An accurate position of the deck operated valves are hard to established, but a  view of the diamond shaped pattern is quite clear. Another detail is the step down which seems to be aft of the vibration damper.
Tore

Very interesting!
 
Tore, do you think its original German floor plating or original floor plating layout?
 
I had believed the original German floor plating was pattern as I have drawn with a
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 13:14
Simon.
I cannot imagine the floorplates were changed in Norway and then changed in Germany once more, I would say it is a pretty good chance the diamond pattern are the original plates.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 13:43
Simon.
I just checked another photo of the engine room deckplates of U 178 and by treating the photo in photoshop I got the pattern of the plates and they are diamond shaped as well as can be seen on the picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 14:00
I just checked my books, and found two pictures of the engine floor plate; One with 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 14:06
Simon.
Just another confirmation of these deviations which we have seen so many of.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 14:16
Tore, I can not found any photo's that show the foot of the rocker arm base (yellow). There one bolt at the front but I imagine you would need more than one large bolt to hold this on to the engine.

Tore, can you give me any idea of the shape of the foot and how many bolts are needed?   

(http://img833.imageshack.us/img833/1786/new1dg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 15:05
Simon.
The visible bolt on the exhaust/ inletvalve pedestal is taking the peak of the load but I am sure there must be a bolt on the other side. Normally it should be a bolt of the same size, but this second bolt could from a stress point of view be smaller although that would be unconventional. I`ll keep looking to see if I can find a solution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 15:23
Simon.
The visible bolt on the exhaust/ inletvalve pedestal is taking the peak of the load but I am sure there must be a bolt on the other side. Normally it should be a bolt of the same size, but this second bolt could from a stress point of view be smaller although that would be unconventional. I`ll keep looking to see if I can find a solution.
Tore

Tore, I was thinking of a 3 bolt fixs (green). Do you think it would only be two (green and orange)?

(http://img812.imageshack.us/img812/2558/new1lvc.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2013, 15:33
Simon.
May be two smaller (green) will do particularly taking the shape of the base plate into account.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 15:36
Added the missing locking ring ;)

Old drawing - left; New drawing - right

(http://img822.imageshack.us/img822/3549/new2sa.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Mar , 2013, 16:42
Simon
We are entering a gray zone for me, I can not remember how the airduct from the Roots blower is entering the airmanifold. It is annoying because I my shelf dismantled the blower entirely ( some 60 years ago) :) . I have superimposed your drawing on top of a layout drawing  to figure out the arrangement. The confusion is on an appearant large ( yellow coloured ) square opening which I thought would be the inlet to the manifold. I just show you the picture may be you have more materials helping you to figure out the connection.
Tore

Tore, what is your suggest in how I should enter the airduct to in the Roots blower? Should I just extent the pipe across to the blower for now?

(http://img844.imageshack.us/img844/2971/new1em.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 01:41
Simon
Airflow Roots blower.
Below is a drawing where I have suggested the airflow (green) of the Roots blower.  This would mean that you just extend the air manifold  so it matches the blower casing, the airduct shall then be flanged vertically to the Roots airduct. ( my assumption). Yellow duct is inlet duct for the aft cylinder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Mar , 2013, 02:03
Tore, just noted a 2nd hot sea water line running aft to the air compressor but only from the starboard engine.

(http://img842.imageshack.us/img842/338/graphic1eh.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 08:14
Simon.
Coolingwater/ corrosion protection.
The Plate 13 shows a combination of systems. The warm water supply to the galley and washbasins are primarily served by the header tank in the tower getting its warm water from the mufflercooling, allthough there is a connection from the engineroom to the galley.
The piping you questioned is connected to the anti corrosion system. The Germans used an anticorrosion oil which emulsified with the coolingwater and thus protected the exposed steel/iron against seawatercorrosion. We never used it. The system works as shown on the system sketch below. You injected the  anticorrosion oil when the cooling watersystem was not in service. Every so so often a barrel of the oil was connected to the hoseconnection at the coolingwater handpump and pumped in to the coolingsystem by hand. By cocks and valves you are able to direct the the oilflow to each of the engines, the exhaustmanifolds and the Junker compressor. The other cooling systems in the aft torpedoroom were not incorporated. The anticorrosion oil for the engines (yellow) is pumped by hand to the main cooling waterchest (valve e is shut) and flows via valve e1 to valve f at the luboilcooler, out at valve d1 and through the engine in the normal coolingwater way. At the group exhaustvalve the main overboard seavalve is shut and the cock f1 is in the crossover position, leading the oil to the main aux. cooling waterpipe which has valve i 1 shut and the oil returns to cock g at the handpump, which is put in the hose/dirty oil drain position and leaves the system.
 When you want to treat the Junker compressor you shut the cock f1( engine coolingwater return via main aux pipe) and the oil flows to the aft torpedoroom (purple pipe) enters the compressor cooling system by open cock 6, (valve c and valve 5 shut,) through the compressor and leave via cock f to the main aux coolingwater pipe as return to the dirty oil hose connection at the handpump. This should explain you smaller pipes and crossover.
Appart from the anti corrosion mode, the main aux cooling pipe is of course used as an ordinary coolingwater pipe for emergency supply to the aft torpedoroom when needed.
Somehow the system would not accept the sketch at 380KB jpg I`ll post it separately.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Mar , 2013, 11:52
Tore, thanks for the information :)

If this pipe what is located on the shipyard drawing is for the Coolingwater/corrosion.

What is the pipe I previously thought was for the Coolingwater/corrosion that runs along the port pressure hull for?

(http://imageshack.us/a/img21/849/new2qc.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 13:39
Simon.
Anticorrosion piping.
I understand your confusion, if you remember a few weeks back we were dealing with the cooling waterpipes fitted to the aft engineroom bulkhead I could not find a pipe which according to the system plate 13 should be connected to the anti corrosion pipe see picture below missing pipe marked red. That`s when I realized plate 13 doesn`t match with the u 995 system. I believe the 1943 and later boats had altered the old anti corrosion system possibly by introducing a special smaller pipe for the treatment.
So my assumption would be: the large pipe going aft at outboard port side is the aux. main coolingpipe from the aux coolingpump in the engineroom and the smaller pipe on the shipyarddrawing from 1943? is the modified pipe for the anticorrosion. The challenge would be to hook the new system to the aft torpedoroom Junker compressor.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 13:42
Simon
This thread does not accept my pictures anymore saying the download is full. I`ll e-mail you the picture.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Mar , 2013, 14:37
Cooling water/Corrosion

(http://imageshack.us/a/img6/7286/new1yi.jpg)

(http://imageshack.us/a/img839/2717/new2i.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 15:14
Simon.
 Very good
Have you been able to find the connecting points ?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2013, 15:37
Simon
The exhaust / inlet valve pedestal.
Having checked the photos once more I believe the most probable way of fixing the pedestal would be two bolts, the one inboard is obvious and the other most probably in the open area as shown on the sketch. In addition each pedestal has two location pins as can be seen on the photo. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Mar , 2013, 17:28
Simon
The exhaust / inlet valve pedestal.
Having checked the photos once more I believe the most probable way of fixing the pedestal would be two bolts, the one inboard is obvious and the other most probably in the open area as shown on the sketch. In addition each pedestal has two location pins as can be seen on the photo. 
Tore

(http://img203.imageshack.us/img203/3685/new1c.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Mar , 2013, 20:08
Top: Cooling water/Corrosion System; Bottom: All

(http://imageshack.us/a/img843/1354/new3tu.jpg)

(http://imageshack.us/a/img11/1176/new1cd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Mar , 2013, 00:12
Simon.
Not bad in spite of outdated system sketches. Apart for that, this system works better no wonder they changed the old ;D .
 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2013, 14:58
Tore, is this a access hatch?

(http://img822.imageshack.us/img822/7794/new1zg.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2013, 15:11
Simon.
Yes I guess it is the access  to the torsional vibration damper.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2013, 15:58
Rocker Arms & torsional vibration damper cover

(http://img13.imageshack.us/img13/6687/engineroom4.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2013, 16:11
Simon.
Torsional vibration damper.
The torsional vibration damper might be an unknown device. In all reciprocating engines torsional vibrations occur which might increase in value and eventually reach levels were the stresses can brake the crankshaft. In order to prevent vibrations to build up, a torsional vibration damper is installed mostly  on the front of the engine and is basically consisting of two masses (rings) spring or hydraulically connected and the uneven massvibrations created by the combustionforces are"chopped up".
There are a number of different designs, below is one not necessarily identical to the type installed on the GW engine.. In general they require little maintenance.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2013, 18:00
Tore, does this line just drain into the bilge?

(http://img339.imageshack.us/img339/7012/new1jy.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2013, 01:50
Simon.
The pipes shown are connected to cocks on the highest points of the ME cooling watersystem and is the ME main venting leading to funnels on a common pipe to the bilge. This  system is easy to mix up with a pipe of same size and in same area going along the engine as well. This pipe is connected to each cooled exhaust outlet bend with no cocks or valves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2013, 14:01
Tore, just finishing off lose end of pipes in my drawing.

I was wondering about this line. Is it a vent line? And went does it go?

(http://img22.imageshack.us/img22/7338/new1gl.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2013, 14:34
Tore, just checking about this line; drain line from the reducing valve and running to the dirty oil tank?

(http://img441.imageshack.us/img441/7618/new2km.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2013, 15:18
Tore, just finishing off lose end of pipes in my drawing.

I was wondering about this line. Is it a vent line? And went does it go?

(http://img22.imageshack.us/img22/7338/new1gl.jpg)
Simon.
I do not believe it is a ventpipe because it is too low and has no shut off cocks. If you look at plate 13 you`ll see a coolingwater pipe going along the engine inboard. There is no such pipe on the engine, I believe it soul go outboard and is the pipe discussed marked red below. As the pipe has a flow of coolingwater it is hooked up to the outlet somehow, plate 13 does not fit very well, but I guess it connect somewhere down in the bilge close to the aft bulkhead, I guess we have to look in this area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2013, 15:26
Tore, just checking about this line; drain line from the reducing valve and running to the dirty oil tank?

(http://img441.imageshack.us/img441/7618/new2km.jpg)
Simon.
I don`t believe to the dirty oiltank, more probably to the relevant system oiltank as it is clean oil.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2013, 15:40
Simon.
Luboil reducing valve.
Are you sure this line is for draining and not manometer?-
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2013, 16:01
Simon.
Luboil reducing valve.
Are you sure this line is for draining and not manometer?-
Tore

Tore, do you think it could be for a manometer? There no manometer marked on plate 14 around this reducing valve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2013, 16:18
Tore, just finishing off lose end of pipes in my drawing.

I was wondering about this line. Is it a vent line? And went does it go?

(http://img22.imageshack.us/img22/7338/new1gl.jpg)
Simon.
I do not believe it is a ventpipe because it is too low and has no shut off cocks. If you look at plate 13 you`ll see a coolingwater pipe going along the engine inboard. There is no such pipe on the engine, I believe it soul go outboard and is the pipe discussed marked red below. As the pipe has a flow of coolingwater it is hooked up to the outlet somehow, plate 13 does not fit very well, but I guess it connect somewhere down in the bilge close to the aft bulkhead, I guess we have to look in this area.
Tore

Tore, I think the chance of finding this connection point would be nearly impossible with the photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Mar , 2013, 01:38
Simon.
I believe you don`t have to wait hooking up the pipeline. Somehow I think you have connected the exhaust manifold venting pipes to the main coolingwater outlet pipe instead of  the drain funnel. If you put the ventingpipe to the funnel and the exhaust cooling header outletpipe where the venting pipe is at present, the system will work. See sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Mar , 2013, 02:29
Simon.
Luboil reducing valve.
I guess the pipe is a manometerpipe. Below is the system, there are two small pipe connections on the reducing valve, the large is the returnpipe to the system oiltank joining the overflowpipe from the luboil cooler and the luboilpump (yellow). The smaller pipe must be a manometerpipe, you want definitely to know that this important valve works with the correct pressure. There is a manometer at the end of the engine as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Mar , 2013, 14:20
Simon.
Luboil reducing valve.
I guess the pipe is a manometerpipe. Below is the system, there are two small pipe connections on the reducing valve, the large is the returnpipe to the system oiltank joining the overflowpipe from the luboil cooler and the luboilpump (yellow). The smaller pipe must be a manometerpipe, you want definitely to know that this important valve works with the correct pressure. There is a manometer at the end of the engine as well.
Tore

Tore, I don't believe this small pipe (yellow) is connected to the bigger pipe ???

(http://img543.imageshack.us/img543/708/new1jv.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Mar , 2013, 14:55
Tore, while looking in to the other pipe above. I was able to track and trail the green pipe with photo's and the shipyard drawing (red arrow = Relief valve 'h') (purple arrow = the section you are see in photo's).

I am now trying to trail the main outlet pipe from the pump (you can see it under the red arrow and ends at the black round circle) I am now trying to decide where to drop is pipe down 1, 2, or 3 ;D

(http://img842.imageshack.us/img842/4030/new2sg.jpg)

(http://imageshack.us/a/img17/5498/new3ez.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2013, 01:59
Simon.
Lubeoil reducing valve.
I agree with you the lager pipe is not connected to the reducingvalve. I shall have to modify my assumption and remove the manometer as I believe the only small pipe
out from the valve have to be the return pipe joining the pipe from the lubeoil cooler and pumprelieve valve to the system oiltank of the relevant engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2013, 04:08
Simon
Luboil reliefvalve drain.
I guess it is easy to get confused here. Just remember the drain from luboil cooler, reducingvalve 3>1.5 atu and the relief valve are all connecting and returns via a common pipe to the relevant system tank. The outlet pipe just before the main luboil pumpsuction flange is a connection to the lub oil discharge pipe. For being a simple gearpump, the luboil pump looks a bit complicated, I believe it is a left over from the direct reversible engine where the gearpump had to operate in both turning direction.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Mar , 2013, 22:03
Tore, if you have time could you please check my pipes. Also I can not work out one of them.

Thanks, Simon.

(http://imageshack.us/a/img831/1641/pipe1r.jpg)

(http://imageshack.us/a/img715/7213/pipe2e.jpg)

(http://imageshack.us/a/img820/7342/new2w.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2013, 01:58
Simon.
As far as I can see you got  it allright. On the cross section shipyard drawing  "spant 26  von vorn gesehen" you shall find the luboil reducing valve ( 3>1.5 atu) spill off pipe P 14/17connecting to the pipe P 14/19 underneath the suction valve of the luboil pump. The pipe marked with yellow question marks is the main coolingwater supplypipe to the engine. Note the they have changed the original thermometers with smaller modern brass thermometer on several places.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2013, 02:42
Simon.
The luboil pump being a gearpump would have a opposite inlet and outlet when the direction of rotation is reversed. As port and starboard engines have different direction of rotation  but using the same pump you`ll see the pipeconnections are placed on different sides of the pumps, that`s why you have  4 connections on the pumphousing and blanked off one of them. Another detail to be included is the revolution counter on the top of the pumphousing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Mar , 2013, 02:51
Simon.
The pipe marked with yellow question marks is the main coolingwater supplypipe to the engine...

I have been trying to put lub oil in this pipe, no wonder why I can not get it to work ;D ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2013, 02:58
Simon.
Mixing oil and water is OK if you use anticorrosion oil but not with lubeoil. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Mar , 2013, 03:03
Simon.
As far as I can see you got  it allright...

Thanks Tore! I should have some new drawings for you toworrow.

The number of pipes around the front of the engines is complex. It very hard to get all the different pipes to fit and also to get them to go correctly under or over the other pipes. I had to spited the engine drawing into two different layers today as you can have parts of the engine that are above the decking and parts of it that are below the decking. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2013, 11:23
Off  topics.
To day it is published by the Norwegian oilcompany Statoil looking for a underwater track to put a gasfield pipe, that they found an U boatwreck laying at 250 m only 2000 m from the famous U-864 ( the mercury boat). The wreck is assumed by the Norwegian Maritime museum to be of U-486 which was sunk by  the British submarine HMS Tapir April 12 1945. U 486 was delivered from Deutsche Werft March 22. 1944. She is reported to have sunk the troopcarrier Leopoldville where 800 US soliders lost their life 2 Royal Navy frigates were on her sinkinglist as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Mar , 2013, 15:13
Tore, extreme piping! ;D

Here is the layout for just the 3 pipes that you can see below P14/13 = Orange; P14/5 = Red &  P14/6 = Blue)

(http://imageshack.us/a/img715/7213/pipe2e.jpg)

(http://img15.imageshack.us/img15/2984/new2my.jpg)
Fig. 1. Three pipes and torsional vibration damper cover.

(http://img405.imageshack.us/img405/4641/new4gz.jpg)
Fig. 2. Torsional vibration damper cover remove.

(http://img94.imageshack.us/img94/7262/new6l.jpg)
Fig. 3. I have remove the Orange pipe and some of the LO lines so you can see how the blue lines connects to the valves.

(http://img801.imageshack.us/img801/1879/new7e.jpg)
Fig. 4. I have remove all but the red lines.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2013, 00:50
Simon.
Your pipe system seems to be OK to me. Just a matter of days before we can start up! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2013, 02:29
Off topics.
U 486.
Further to my report of the find of U 486 follows a photo of the wreck and crew as well as SS Leopoldville which she torpedoed Christmas eve 1944. The troopship sank slowly (2 1/2 hours) in spite of that and due to holyday leaves,  rescue vessels without crew and mishandling almost 800 US troops lost unfortunately their lives.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Mar , 2013, 13:19
Next few pipes...

Pink = LO Cooler to Coll & Dist Manifold
Violet = Runs toward the pump (which I can not remember it name).
Green = from LO pump to pink line.
Yellow = from reducing valve to Green line.


(http://imageshack.us/a/img854/9346/new1ce.jpg)

(http://imageshack.us/a/img803/8096/new2z.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Mar , 2013, 13:36
Simon.
Your pipe system seems to be OK to me. Just a matter of days before we can start up! ;D
Tore

High pressure air starting system hookup and ready  ;)

(http://img708.imageshack.us/img708/4308/new1uk.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2013, 14:06
Simon.
Don`t forget the handle on the starting air wheel! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2013, 01:11
Simon.
Pipes.
Your new supply of spaghetti seems to me to be OK ;D . One question though ;) . On the pipe layout plate you have correctly placed the violet pipeline outboard and to the governorservo for the fuelrack. However before entering the servo you have two branch off to the Roots blower. Have you found these branch off pipes on some photos or drawings? The reason for the question is that this violet pipe is shortcutting the reducing valve 3>1.5 atu in order to supply the servo with oilpressure of 3 atu whereas the luboil pressure should be 1.5 atu. The lubrication points on the Roots blower are four bearings and the gear/timing gear,plus clutch which really do not need higher pressure than the rest of the lubrication points of the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Mar , 2013, 03:00
Tore, yes I have a photo (below). You can clearly see the two lines to the Roots blower.

(http://img209.imageshack.us/img209/4520/p1100217m.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2013, 06:48
Simon
Luboil 3 atu.
A very convincing photo. I cannot explain why the Roots blower has a higher luboil pressure, but I guess it would be on all the lubricating point of the blower not only the forward rotary vane bearings. Below I have marked the relevant luboil pipeinlets which I assume is then connected to the violet 3 atu luboilpipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 14:16
Lines for measuring instruments for LO Filter (Violet - Black - Violet)

(http://img703.imageshack.us/img703/4552/new2d.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 14:24
Piping around the torsional vibration damper cover - finish :)

Also fix the piping for the air starting system.

(http://img201.imageshack.us/img201/7719/new3p.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Mar , 2013, 14:30
Simon.
The pipes for the differential oilfilter manometer are placed where they should be. To me they look a bit larger than the impression I had, they do not deliver any oil like the pipe to the servo, just static pressure.  I believe they were small copperpipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 14:32
Floor cover & torsional vibration damper cover

(http://img822.imageshack.us/img822/2874/new4w.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 14:34
Simon.
The pipes for the differential oilfilter manometer are placed where they should be. To me they look a bit larger than the impression I had, they do not deliver any oil like the pipe to the servo, just static pressure.  I believe they were small copperpipes.
Tore

In the drawing they are 20 mm - steel, should I change them to 15 mm copper?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Mar , 2013, 14:40
Simon.
Your pipes around the torsional vibration damper seems OK to me . The spilloff pipe from the pressure reducing valve has the right dimension and about the same as the manometerpipes should have.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Mar , 2013, 15:05
Simon.
I just had a look at your manometerpipe for the supercharger manometer and I guess that would be about the right dimension.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 15:07
Tore, do these small pipes like like copper or steel?

Also the nuts are bronze :o

(http://img801.imageshack.us/img801/3613/new6w.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2013, 15:11
Simon.
I just had a look at your manometerpipe for the supercharger manometer and I guess that would be about the right dimension.
Tore

Yes, that one is 15 mm. I will change my other pipes.

Tore, do you think all the 15 mm pipe would be copper?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2013, 01:01
Simon.
If you look at the photos from U-995, the way they are bend and those which are broken or disconnected I would assume they are copperpipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Mar , 2013, 01:53
Simon.
If you look at the photos from U-995, the way they are bend and those which are broken or disconnected I would assume they are copperpipes.
Tore

Thanks Tore. I will update my drawing tomorrow.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2013, 02:25
Simon.
I guess the nuts and cocks of the 15 mm pipes are all brass. The luboil filter differential manometer has two inlets and cocks for the pipes in and out of the filter. See photo below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Mar , 2013, 13:02
Tore, I was thinking about other smaller lines.

Do you think these small lines on the engine would also be copper?
(http://img46.imageshack.us/img46/1466/new1x.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2013, 13:21
Simon.
Yes I believe all the 15 mm pipes most probably are copper and the cocks and couplings brass.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Mar , 2013, 13:24
Simon.
I guess the nuts and cocks of the 15 mm pipes are all brass. The luboil filter differential manometer has two inlets and cocks for the pipes in and out of the filter. See photo below.

(http://img844.imageshack.us/img844/4732/new2ov.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2013, 15:59
Simon.
Excellent!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2013, 12:50
Updated engine

(http://img268.imageshack.us/img268/1141/new1vi.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2013, 13:50
Simon.
Looks very good, I have just a few minor remarks. The header collectingpipe is partly of copper, I believe it is steel all the way. The venting pipe from the cooling waterpipe crossing the exhaust manifold flanges seems to be on the large side, I believe the upper branch off are small venting pipes which  normally should not be connected to the cooling watersystem but the drainfunnel. The branchoffs from the lower coolingwater bends are drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2013, 14:17
Simon.
Looks very good, I have just a few minor remarks. The header collectingpipe is partly of copper, I believe it is steel all the way. The venting pipe from the cooling waterpipe crossing the exhaust manifold flanges seems to be on the large side, I believe the upper branch off are small venting pipes which  normally should not be connected to the cooling watersystem but the drainfunnel. The branchoffs from the lower coolingwater bends are drain.
Tore

Tore, I will fix the header collecting pipe.

I will reduce the main venting pipe from 30 mm to 20 mm and the branch off from 30 mm to 15 mm.

I do not understand the other thing you are talking about  :( "normally should not be connected to the cooling watersystem but the drainfunnel. The branchoffs from the lower coolingwater bends are drain." Have I connect the pipes incorrectly?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2013, 15:20
Simon.
Instead of connecting the exhaust manifold cooling bend ventpipe to the manifold coolingwater outlet pipe, I  guess it should end in the drainfunnel. The header cooling waterpipe might be connected to the same place as the ventpipe instead.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2013, 16:09
Simon.
Instead of connecting the exhaust manifold cooling bend ventpipe to the manifold coolingwater outlet pipe, I  guess it should end in the drainfunnel. The header cooling waterpipe might be connected to the same place as the ventpipe instead.
Tore

Sorry Tore, I am totally lost that you mean. I can not workout that pipes you are talking about :(

If you have time tomorrow, could you please draw me one of your drawing, to help me understand, thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 Mar , 2013, 17:52
Exhuast Outlets update

(http://img834.imageshack.us/img834/7012/new1jy.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 00:43
Simon.
It was late yesterday I understand your confusion ;) . Below are pictures which possibly explain the system. The exhaust manifold has two types of cooling water bends crossing the flanges, upper and lower. Upper bends have a small ventingpipe, yellow, may be 20 mm. As all ventingpipes are placed on the highest point in the system and goes to a drainfunnel, you don`t introduce the air into the system again. The lower pipebends have drains on the lowest point, violet, these small pipes may be 30mm, join the header pipe,red, before they merge the main coolingoutlet of the exhaustmanifold and then eventually overboard. I have not been able to trace all details so the correction is based on common engineering.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 02:27
Exhuast Outlets update
  • Added better shading.
  • Added casting seams.
  • Added temperature sensors.
(http://img834.imageshack.us/img834/7012/new1jy.jpg)


Simon.
You engine is growing into the real thing with all the details gradually coming up it shall definitely be impressive when all the correct details are in place.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: TopherVIIC on 01 Apr , 2013, 09:24
Simon
Your drawing skill is incredible.... Well done Sir!
Christopher
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Apr , 2013, 12:32
Simon.
It was late yesterday I understand your confusion ;) . Below are pictures which possibly explain the system. The exhaust manifold has two types of cooling water bends crossing the flanges, upper and lower. Upper bends have a small ventingpipe, yellow, may be 20 mm. As all ventingpipes are placed on the highest point in the system and goes to a drainfunnel, you don`t introduce the air into the system again. The lower pipebends have drains on the lowest point, violet, these small pipes may be 30mm, join the header pipe,red, before they merge the main coolingoutlet of the exhaustmanifold and then eventually overboard. I have not been able to trace all details so the correction is based on common engineering.
Tore

Thanks Tore!

I was looking at the wrong drain funnels and I have been looking at the port side of the plate 14 and I did not realise the inboard part of the exhaust Cooling-water system drawing was the venting side :-[
 
I noted on plate 14, that each cooling water bends crossing the flanges has it own venting pipe. Should I do the same or do you think there were all join together to a common drain valve?
 
I also found a rare photo of the drain line :)
(http://img708.imageshack.us/img708/2466/new1nu.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Apr , 2013, 13:00

Simon
Your drawing skill is incredible.... Well done Sir!
Christopher

Thanks Christopher.

There now over 55,000 objects in the top view of the engine room.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 13:16
Simon.
It is difficult to give a 3 dimensional impression on a 2 dimensional sketch. If you look at the yarddrawing side view it seems the ventpipes are merging in a common pipe to the drain, I guess the pipe ends with a common cock in the funnel as all the ventpipes-
Your picture of the ventpipe indicate that this small pipe is a copper pipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 13:31
Simon.
Have you counted the 55.000 objects?? :o  I wonder how many the final result shall be at the end, however its not the amount of objects but how they are put together which is important, after all the thing has to work and I am sure it will in the end ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Apr , 2013, 14:06
Simon.
Have you counted the 55.000 objects?? :o  I wonder how many the final result shall be at the end, however its not the amount of objects but how they are put together which is important, after all the thing has to work and I am sure it will in the end ;D .
Tore

In the main drawing of U-1308 there a total of 190,000 objects ;D

I been looking at some more photo's that perhaps show that each vent pipe from the upper cooling water bend has it own drain line. Base on the size of the pipe I can see coming out of the 1st photo of the upper cooling water bend and the photo below I can see two pipe of a similar size running to the funnel.

Tore, that do you thing?

(http://img15.imageshack.us/img15/149/munsterlaboe14151120124.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 14:54
Simon.
The pipe sketch shows two separate vent pipes to the funnel, but has not any exhaust manifold centerflange with cooling waterbend.The shipyard drawing shows a centerflange with vent connection nut and no pipe, but the two aft flanges have ventpipes on the upper cw.bends  merging into a common pipe. To me it seems strange that the center flange bend do not have a ventpipe. If we assume the  center flange coolingwater bend has a separate ventpipe and the two aft bend have vent pipes merging into one you end up with two ventpipes in the funnel. I would not be able to explain why.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Apr , 2013, 15:09
Simon.
The pipe sketch shows two separate vent pipes to the funnel, but has not any exhaust manifold centerflange with cooling waterbend.The shipyard drawing shows a centerflange with vent connection nut and no pipe, but the two aft flanges have ventpipes on the upper cw.bends  merging into a common pipe. To me it seems strange that the center flange bend do not have a ventpipe. If we assume the  center flange coolingwater bend has a separate ventpipe and the two aft bend have vent pipes merging into one you end up with two ventpipes in the funnel. I would not be able to explain why.
Tore

Tore, could it be that the two aft bend get hotter than the centre flange consequently the two aft flange need to be vented more offend?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2013, 23:37
Simon.
Coolingwaterflow and venting is a science which sometimes is not easy to understand, the basic is that air pockets obstructs the coolingwaterflow and thus the cooling. Sometimes you can have interference between the pipes when two pipes are merging. I have a possible idea which require a bit further investigation hold on till tomorrow. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Apr , 2013, 09:21
Simon.
Coolingwater venting.
The CW systemdrawing shows the two aft exh. flanges having separate drain with cocks to the funnel however it does not show any exh. manifold center flange or cooling water crossing bends which we  see is on the manifold. On the shipyard drawing a vent/drain pipe is going all along the engine but only the aft two flanges ventpipes are connected. The centerbend shows connection for a venting pipe but no pipe. The forward bend ( warm CW water return) shows no venting.
Your photo of the CW ventpipe is presumably from the center CW bend, and pointing downwards. As shown on the photo below the CW warmwater outlet bend forward of the manifold has a connection for ventpipe and might have a ventpipe as well.
We are not able to see any common vent pipe along the engine. On these fact we have to make our guesses.
I assume all the bends have venting, based on your finding of the two ventpipes it could be that the four bend ventings are connected in pairs and end up with two pipes and cocks in the funnel. Sorry this is the only idea I have right now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Apr , 2013, 13:03
the four bend ventings are connected in pairs and end up with two pipes and cocks in the funnel...

That sound very German, have backup ;) I will update my drawing this afternoon. Thank Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Apr , 2013, 13:55
Tore, here are the updated lines.

(http://img826.imageshack.us/img826/7589/engineroom5.jpg)
Scale (Full) 1 pixel = 2.25 mm/(Forum) 1 pixel = 9.9 mm
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Apr , 2013, 14:09
Simon.
You are getting close to completion. I guess the Gruetzner lubricator drive and supercharger clutch handle shall come later. So far everything looks fine to me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Apr , 2013, 12:07
Hi Tore

Just an update on the engine room drawings. I am presenting at an Avalanche Conference next month, and currently spending more time working on my presentation. So the amount of drawing I am doing is slowing down for the next few weeks.

Slowly going back to the real world  :(

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Apr , 2013, 12:53
Simon.
I understand your dilemma. However avalanches in countries like ours is an important topic. Right now we are in a middle of an avalanche season, the worst ever, and we have a lot of casualties this winter. My concern is however a completely different one. I am moving up to my farm for the summer season and the access to internet is limited but I`ll be there. Looking forward to your update.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Apr , 2013, 13:04
Just the other day I saw an article about how big the avalanche season is, for this winter, it had a great picture of a huge avalanche crossing a road.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Apr , 2013, 13:28
Simon.
Right now they are trying to dig out 3 persons which probably got instantly killed and  buried under 6 meters of compact snow a week ago. They have been using sound cannons and dynamite for 3 days to get safely in to this narrow valley. The snow is almost like concrete and impossible to dig by hand see photo taken today.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Apr , 2013, 02:16
Simon/OldNoob
Exhaust outlet.
Looking at some of my old photos to find floodgate details I came over two pictures which I shot during KNM Kauras drydocking in 1953. The pictures although of bad quality show clearly the exhaustoutlet I guess. Remembering Simons question on the style 6 exhaust let I was  astonished to see that my old U 995 seems to have style 6 execution.
Have a look at my bad photos and the photo of present day U-995 with a welded plate on the location where I presume the style 6 outlet should be.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Apr , 2013, 03:13
Simon/OldNoob
Exhaust outlet.
Looking at some of my old photos to find floodgate details I came over two pictures which I shot during KNM Kauras drydocking in 1953. The pictures although of bad quality show clearly the exhaustoutlet I guess. Remembering Simons question on the style 6 exhaust let I was  astonished the my old U 995 seemed to have style 6 execution.
Have a look at my bad photos and the photo of present day U-995 with a welded plate on the location where I presume the style 6 outlet should be.

Tore, this is fantastic! I original thought that U-995 have Style 6 back April 2010.
http://models.rokket.biz/index.php?topic=280.msg5402#msg5402 (http://models.rokket.biz/index.php?topic=280.msg5402#msg5402)

But by March 2011 I was not 100% sure so I remove it from the list.
http://models.rokket.biz/index.php?topic=280.msg9026#msg9026 (http://models.rokket.biz/index.php?topic=280.msg9026#msg9026)

It great to see my original thought was correct :)

Tore, does this mean that you will need to change you model ;)

Also an update on the engine room, it has taken me a lot longer to do my Avalanche presentation than I thought. I did my first read through last week and it turn out to be way too long. So I had to rework it a lot to make it shorter.

I will continue working on the engine room drawing before winter starts here, but there is no way I can finish it before that time :( I believe I still have about four weeks of drawing to have it totally finish. It
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Apr , 2013, 03:23
Simon/OldNoob
Exhaust outlet.
Looking at some of my old photos to find floodgate details I came over two pictures which I shot during KNM Kauras drydocking in 1953. The pictures although of bad quality show clearly the exhaustoutlet I guess. Remembering Simons question on the style 6 exhaust let I was  astonished the my old U 995 seemed to have style 6 execution.
Have a look at my bad photos and the photo of present day U-995 with a welded plate on the location where I presume the style 6 outlet should be.

Tore, I was just thinking do you think that Style 6 was added at Trondheim?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Apr , 2013, 06:03
Simon.
I shall eventually change my KNM Kaura model. I don`t think the style 6 was introduced in Trondheim. I am busy checking the exhaustoutlet on U- 1202 which looks as if  she had the style 6.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Apr , 2013, 06:52
Simon.
Style 6 exhaustoutlet.
After checking the photo materials in my files I have found a fairly reliable evidence that U-1202 was equipped with the style 6 outlet as well. As you see on the photo below of KNM Kinn (ex U-1202) the casing was painted black from the waterline and a bit up, strongly indicating that the exhaustoutlet is submerged on that spot. Further the outlet is placed a bit abaft of the conventional above surface outlet. I assume the sparkarrestor was kept unchanged and the outletpipe from the sparkarrestor led a bit abaft in the narrow submerged space between the pressurehull and casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Apr , 2013, 01:24
Simon.
I have enjoyed studying you amazing latest drawing of the main engines. As mentioned to you, I have some minor remarks knowing your are keen on details. ;)
It looks as if you have made the nameplates at the maneuvering stand of brass, they are of aluminium. See photo.
The inlet and exhaust valvestems have a lockingwire on the valve clearance nut. See photo.
The lever for the supercharger clutch/natural aspiration rotating inletvalves is missing. See photo.
The handle for the main starting airwheel is missing. See photo.
The counter for the revolutions on top of the lube oilpump is, as far as I can see, missing. See photo.
As said these are minor details probably known to you and may be you have decided to omit same. ;D
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Apr , 2013, 13:57
Simon.
I have enjoyed studying you amazing latest drawing of the main engines. As mentioned to you, I have some minor remarks knowing your are keen on details. ;)
It looks as if you have made the nameplates at the maneuvering stand of brass, they are of aluminium. See photo. - FIX
The inlet and exhaust valvestems have a lockingwire on the valve clearance nut. See photo. - I decide to ignore this wire this at this stage, it
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Apr , 2013, 23:31
Rudiment of direct reversing.
As previously discussed the later main dieselengines of the VIIC and VIIC/41s were not equipped with a direct reversible device. These U-boats maneuvered by the E-motors as the common practise for submarines. Hence the vertical reversing cylinder and a few other items were not installed, however a few reversing parts remained and amongst these the name plate and the supportstand for the reversing handle. Below is a photo of this item which Simon correctly has incorporated in his drawing. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Apr , 2013, 18:54
Hi Tore

I am wondering about the flooring in the galley.

Can you remember or know if the flooring in the galley was make up of numerous smaller plates like the engine room or one or two large plates? Do you need access to piping under the galley?

Thanks, Simon.

(http://img89.imageshack.us/img89/742/new1r.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 00:44
Simon.
I guess there are about six access covers, may be one or two are in the batteryswitch compartment. Access would be needed as follows:
1. Sounding pipe for freshwater tank.
2. Sounding pipe for dirtywater tank.
3. Two valves for Limeconnection battery compartment
4. Two valves for natural galleybilge drain to engineroom.
Se pictures below.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 00:54
Simon.
Sorry somehow the galley drainpipes came up twice. Here is the missing soundingpipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 01:33
Simon.
I guess there are about six access covers, may be one or two are in the batteryswitch compartment. Access would be needed as follows:
1. Sounding pipe for freshwater tank.
2. Sounding pipe for dirtywater tank.
3. Two valves for Limeconnection battery compartment
4. Two valves for natural galleybilge drain to engineroom.
Se pictures below.
Tore

I read somewhere that the Lime system got a complete redesign for the late war Type VIIC's.

I think will do similar size floor plates as the engine room
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 01:42
Simon.
I guess you are right, we never made use of the limesystem. May be you should make the sounding openings as in the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 01:44
Here a rare photo of the original German floor plate. Its look like the plates are about the same size as the engine room with smaller access hatches.

I imagine the pipe on the right is the sounding for the waste water?

(http://img203.imageshack.us/img203/4025/new1kr.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 01:52
Simon.
I guess you are right, we never made use of the limesystem. May be you should make the sounding openings as in the engineroom.
Tore

I can not remember which book is was in, perhaps in The U-Boat: The Evolution and Technical History of German Submarines, but it said that the German move the outflow lines of the lime system below the batteries previously the lines run above the batteries.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 01:55
Simon.
The location for the pipe is rigth for the waste water tank, so it could be.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 02:06
Tore, I was looking Plate 21:  Fresh water, wash water, waste and sanitary systems http://www.uboatarchive.net/U-570Plate21.htm (http://www.uboatarchive.net/U-570Plate21.htm)

I imagine they remove the hot water pipe between the Galley and Officers Quarters which run under the wooden deck, on the late war Type VIIC's?

 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 02:17
Tore, I was just wondering did you ever changes the batteries on KNM Kaura or are they original German batteries?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 04:44
Warm washwater.
I honestly don`t remember. I assume the horizontal waterpump port fwd engineroom which is connected up to the system, see previous discussion June 5th 2012, was installed after my time. The warm water heater on the aft bulkhead  in the fwd. torpedoroom next to the officers bathroom was definitely installed after my time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 04:55
Batteries.
All the batteries were changed and new batteries were made by the Norwegian submarine battery manufacturer. As a part of my education I even took part in the "production" making my own car battery. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 14:15
Tore, how the floor look like in the galley now?

(http://img850.imageshack.us/img850/6483/new1j.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 14:41
Simon.
It looks fine to me. A small detail, the small accesshatch close to the range has a larger oval hole. It looks to me that you can see the top of a sounding stick through the hole.  In that case it would be the sounding for the freshwatertank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 30 Apr , 2013, 23:11
Warm washwater.
I honestly don`t remember. I assume the horizontal waterpump port fwd engineroom which is connected up to the system, see previous discussion June 5th 2012, was installed after my time. The warm water heater on the aft bulkhead  in the fwd. torpedoroom next to the officers bathroom was definitely installed after my time.
Tore

Tore, how did the waste water get off the boat? Was it through the bilges then out to sea?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 23:46
Simon.
Wastewater drain.
The wastewater tank has a connection to the bilgewaterpump in the controlroom as seen on the sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2013, 23:55
Simon.
Further to my last post. As you see  on the sketch I believe it is a washbasin  in the crews WC as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2013, 08:56
Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm (http://uboatarchive.net/U-570GeneralPlan.htm))


--
Thanks, regards
Maciek

Maciek.
The head tank or may better buffertank is not a big tank,just big enough to keep a positive head in the system. It is fed from the coolingwater outlet at the exhaustsilencer, the location is about where I put the arrow on the drawing below.
Tore

Simon and Maciek.
I remember you had a question about the watercompensating tank for the fueltanks back in November last year. When looking through my drawingfiles today I came over a GA drawing of the VIIC/41 showing the 1944/45 execution. You are able to see the small tank located in towercasing on the sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 May , 2013, 13:24
Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm (http://uboatarchive.net/U-570GeneralPlan.htm))


--
Thanks, regards
Maciek



Maciek.
The head tank or may better buffertank is not a big tank,just big enough to keep a positive head in the system. It is fed from the coolingwater outlet at the exhaustsilencer, the location is about where I put the arrow on the drawing below.
Tore

Simon and Maciek.
I remember you had a question about the watercompensating tank for the fueltanks back in November last year. When looking through my drawingfiles today I came over a GA drawing of the VIIC/41 showing the 1944/45 execution. You are able to see the small tank located in towercasing on the sketch below.
Tore

Great found Tore!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 May , 2013, 14:12
Tore, the arrow coming out of the watercompensating tank is a drain?

http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 May , 2013, 14:31
Tore, I imagine late war water compensating tanks would be were galvanized?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2013, 14:40
Simon.
It could very well be galvanized.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2013, 14:46
Simon
The non coloured arrow probably indicate an outbord drain, not overflow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 May , 2013, 15:11
Tore, would the water level be over both pipes?

How does it looks so far?

Will add the piping under the water compensating tank next summer

(http://img23.imageshack.us/img23/9567/new1wr.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 May , 2013, 15:22
Hi Tore,

Tore, thanks for answer. Could you mark the location of head tank in conning tower (if possible, using this drawings: http://uboatarchive.net/U-570GeneralPlan.htm (http://uboatarchive.net/U-570GeneralPlan.htm))

I remember you had a question about the watercompensating tank for the fueltanks back in November last year. When looking through my drawingfiles today I came over a GA drawing of the VIIC/41 showing the 1944/45 execution. You are able to see the small tank located in towercasing on the sketch below.


Very interesting. Its the first trace of this thank, thank  you very much for locating it.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 May , 2013, 00:23
Simon.
I believe this is OK. However the waterlevel when surfaced and dieselengines running would be as indicated on the drawings below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 May , 2013, 00:49
Simon.
I should perhaps mention you have a variation in the waterlevel between stopped and running diesels. The supplyline ends almost half way in the tank ( red) preventing the tank to be emptied at stopped engines. The overflow ( blue) ends almost at the top allowing a certain amount of "play" in the watertank volume, but always ensure a positive head surfaced and submerged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 May , 2013, 08:42
Tore,


I have got picture of the aft side of the attack periscope well. Could you tell me, what are these four pipes with sight glasses?
The three pipes between them with outlets in one funnel look like drains of the air intake, exhaust and diesel engine intake trunk head valves.


(http://imageshack.us/a/img11/4940/sehrohrschacht.png)(http://imageshack.us/a/img705/4940/sehrohrschacht.png)


http://www.kubische-panoramen.de/index.php?id_id=5378&p=i (http://www.kubische-panoramen.de/index.php?id_id=5378&p=i)


--
Thanks, regards

Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2013, 23:26
Maciek.
I am not 100% sure, but guess they are all drains from what you assume. Two drains from each of the two ventilation air inlet shaft, at least one from the main dieselair inletvalve,and I assume ( can`t remember) some from the schnorchel system. I shall study the matter a bit further and hopefully be able to give you further details. Unfortunately I am in a remote area for the summer and have only limited access to a very slow broadband so it takes time.  :(
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2013, 15:32
Maciek
I assume your question can be split in two answers. The pipes ending in a funnel are drains from the air ventilation inlet valves and main diesel inletvalve, see sketch below. The drain via sigthglasses ends in the bilge through a muffler and is checkdrain from the regulating and RFO tank 1 port and stb. and possibly also the check drain from the negative buoyancy tanks port and stb as I have not been able to trace this muffler drain in the fwd. controlroom, see sketches below. As usual the real systems are not a copy of the schematic sketches.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 May , 2013, 16:27
Maciek
I assume your question can be split in two answers. The pipes ending in a funnel are drains from the air ventilation inlet valves and main diesel inletvalve, see sketch below. The drain via sigthglasses ends in the bilge through a muffler and is checkdrain from the regulating and RFO tank 1 port and stb. and possibly also the check drain from the negative buoyancy tanks port and stb as I have not been able to trace this muffler drain in the fwd. controlroom, see sketches below. As usual the real systems are not a copy of the schematic sketches.

Tore, I was looking at drain line for the Diesel Air Main Intake. It seen very high in the intake line and would leave a large amount of sea water in the intake line. This were a 2nd drain line?

(http://imageshack.us/a/img15/6481/new1gd.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2013, 01:14
Simon
You are of course right, howewer this is a simple sketch possibly made by a German engineering officer to show the first type of standard schnorchel having a different airinlet as the next generation installed on U-995.  As the centerline of the valvespindle is wrongly offset, the drain gives a faulty impression of leaving substantial water in the shaft. The drain, I believe is more like a leakage check rather than a complete shaft drain. The sketch shows more the system than the real execution.
I assume it is a different need for drain for the diesel inlet air and the ventilation air. The diesel shaft  is acting almost like a very big drain having its outlet in the engine room bilge, in bad weather the water was constantly gushing down in the bilge and the bilge pump was running all the time. You would not like have the same amount of water in the ventilation shafts, hence a more elaborate drainage for this system at the main inlet.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 17 May , 2013, 02:57
Hi Tore,
The drain via sigthglasses ends in the bilge through a muffler and is checkdrain from the regulating and RFO tank 1 port and stb. and possibly also the check drain from the negative buoyancy tanks port and stb as I have not been able to trace this muffler drain in the fwd. controlroom, see sketches below.


Thanks for your explanation. What was the function of "check drain"? I'm little confused, as these pipes (with sightglasses) seem to be connected to the top part of regulating and RFO tanks. So aren't they rather vent lines? But if so, what for are these sight glasses? What can be observed there?


And these mufflers - I suppose they were to silence the air escaping from the flooded or pressurized tanks. But how do they work/look like?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 17 May , 2013, 05:36
Hi,


And one more question - do you remember, what kind of electronic device is it? It is located in the forward part of control room, at port site.
(http://img402.imageshack.us/img402/166/u995029.jpg)


Is it German, war-time? Was it installed, when U-995 served in Norwegian Navy?


Some time ago I have asked about this part of electronic equipment. Initially I was convinced, that this is post-war, unrelated with U-Boats, electronic device. But then accidentally I have found some informations which made me change my mind. I have started some researches and the results are in this article:
http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats (http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats)
I hope you find it interesting. Any feedback is welcomed.


To answer my initial question, the device I have asked is part of FuMO 30 - early version of German radar for U-Boats.
I'm also 100% sure, that U 995 was not equipped with any active sonar gear (except echo depth sounding device).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2013, 07:19
Maciek.
 May be I better take one question at the time that's probably enough for an old man. Muffler comes in a wide range of design, the basic for a gas (air ) muffler is it destroys the vibration energy so the air escapes without noise. I never looked inside the U 995 air muffler but I am pretty sure it consisted of some kind of baffle plates and the air escaped though holes in the outer casing. If you look at the photo of the Kubische Panorama you are able to see the holes. Below is an example how a muffler looks inside.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2013, 08:00
Maciek.
I agree with you check drain, was not the best word for the pipes. Venting and air supply is probably more correct. The purpose of the system  has two tasks. As you correctly are stating, venting. This is particularly important for the Q tank ( Untertriebzelle port and stb.) which is used for emergency quick diving and silencing is essential.
As the regulating tanks, are not connected to the pressure water compensating system , the pipes are used, when the regulating tanks are used as fueltanks, as  air pressurepipes to the tanks in order to transfer the fuel to the internal fuelsystem, as you see it is possible to use this LP air to the saddle ballast tanks 2 and 4 port/stb as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2013, 08:08
Maciek
Sigthglasses are used for checking the drain from the tanks like fuel, water, air etc. An important item, you don`t want to have fuel in the bilge.
Obviously if you used funnels for these pipes the purpose of the mufflers are gone.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2013, 23:58
Maciek.
Active sonar/ radar.
I think you are correct, I believe I can remember we did not have the active sonar. I read the article on the german radar development with interest and I can`t  contribute very much except to mention right after the war it was a general distrust of anything related to german radar. In my time I believe we had the original U- 995 equipment. We tried it several times with very little success. The worst experience was up at Lofoten Island, Northern Norway an early very foggy morning. These  island rise up from the sea like a wall 100- 300 meters and we  surfaced just outside the islands which were impossible to see and we tried out the radar. There was no echo, so we tried the old fashioned system, the whistle, and got immediately an echo. When the morning fog disappeared we discovered we were about 400- 500 meters from an impressive rockwall. After that we discarded the german radar, probably unjust, but in those days the navigators were still very skilled in navigating without electronics.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 May , 2013, 02:11
Hi Tore,


thanks for your answers.


May be I better take one question at the time that's probably enough for an old man. Muffler comes in a wide range of design, the basic for a gas (air ) muffler is it destroys the vibration energy so the air escapes without noise. I never looked inside the U 995 air muffler but I am pretty sure it consisted of some kind of baffle plates and the air escaped though holes in the outer casing. If you look at the photo of the Kubische Panorama you are able to see the holes. Below is an example how a muffler looks inside.


Thanks, I did not notice these holes - now it's clear for me.


As the regulating tanks, are not connected to the pressure water compensating system , the pipes are used, when the regulating tanks are used as fueltanks, as  air pressurepipes to the tanks in order to transfer the fuel to the internal fuelsystem, as you see it is possible to use this LP air to the saddle ballast tanks 2 and 4 port/stb as well.


Sigthglasses are used for checking the drain from the tanks like fuel, water, air etc. An important item, you don`t want to have fuel in the bilge.
Obviously if you used funnels for these pipes the purpose of the mufflers are gone.


Well, I must confess, I do not understand it. How can the fuel or water get to this pipe? During which operation? And when the fuel (or water) get there, does not affect the muffler?


The matter why the funnels are not used, is now clear for me.


--
Thanks, regards

Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 May , 2013, 02:15
Active sonar/ radar.
I think you are correct, I believe I can remember we did not have the active sonar. I read the article on the german radar development with interest and I can`t  contribute very much except to mention right after the war it was a general distrust of anything related to german radar. In my time I believe we had the original U- 995 equipment. We tried it several times with very little success. The worst experience was up at Lofoten Island, Northern Norway an early very foggy morning. These  island rise up from the sea like a wall 100- 300 meters and we  surfaced just outside the islands which were impossible to see and we tried out the radar. There was no echo, so we tried the old fashioned system, the whistle, and got immediately an echo. When the morning fog disappeared we discovered we were about 400- 500 meters from an impressive rockwall. After that we discarded the german radar, probably unjust, but in those days the navigators were still very skilled in navigating without electronics.


Your recollection about unreliable German radar is consistent with few informations about its operational usage.
The story about  "old fashioned system" - the whistle is amazing.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2013, 13:20
Hi Tore,


thanks for your answers.


May be I better take one question at the time that's probably enough for an old man. Muffler comes in a wide range of design, the basic for a gas (air ) muffler is it destroys the vibration energy so the air escapes without noise. I never looked inside the U 995 air muffler but I am pretty sure it consisted of some kind of baffle plates and the air escaped though holes in the outer casing. If you look at the photo of the Kubische Panorama you are able to see the holes. Below is an example how a muffler looks inside.


Thanks, I did not notice these holes - now it's clear for me.


As the regulating tanks, are not connected to the pressure water compensating system , the pipes are used, when the regulating tanks are used as fueltanks, as  air pressurepipes to the tanks in order to transfer the fuel to the internal fuelsystem, as you see it is possible to use this LP air to the saddle ballast tanks 2 and 4 port/stb as well.


Sigthglasses are used for checking the drain from the tanks like fuel, water, air etc. An important item, you don`t want to have fuel in the bilge.
Obviously if you used funnels for these pipes the purpose of the mufflers are gone.


Well, I must confess, I do not understand it. How can the fuel or water get to this pipe? During which operation? And when the fuel (or water) get there, does not affect the muffler?


The matter why the funnels are not used, is now clear for me.


--
Thanks, regards

Maciek



Maciek.
F. inst when the regulating tanks are used as RFO tanks you are filling fuel into the non watercompensated, regulating and RFO tanks 1 port and stb you open the valves in the violet lines to the tanks and fuel is entering the tanks usually by gravity,  further you open the valve as shown on the green pipes in order to let the air escape  from the tanks via the sigth glasses and muffler. You check through the sigthglasses to be sure when the tank is nearly full that only air and no fuel enters the bilges. The mufflers are not very  sensitive to clean non aggressive liquids.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 May , 2013, 02:12
Thanks Tore, now I understand.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 May , 2013, 13:49
Maciek.
Muffler inboard venting  Q tank.
I should probably mention an important use for this system. As you most probably know a common practise for a submarine attack is to fire your torpedoes and then go deep.
This should be done as quick as possible and off course very silent. That is the purpose of the Q tanks and the discussed inboard venting.At the attack the Q tank Kingstons are open. At the COs order the main inboard ventvalve is open and both Q tanks are quickly filled via the Kingstons (yellow line venting mode) the submarine sinks and the inboard venting sound is silenced leaving no sound and outside airbubbles to reveal your position. The main vent  is immediately shut as seawater is coming into the bilge and a man is stand by at the  Q tanks main blowingvalve waiting for the order to blow the tank empty ( green line blowing mode) at required depth. May be all this is pretty obvious for you but anyhow I thougth it  worth to mention.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2013, 14:35
High voltage E-system Blohm & Voss drawings.
Looking into some of my papers, I came across the other day a drawing made by the shipyard Blohm & Voss-Steinwarder and marked U-101 corrected 1943.It shows the complete lay out of the high voltage electric plant of VII C as made by Blohm & Voss, I guess I have kept it from my first year on board KNM Kaura ex.U-995. I realize this can only be of interest for some very few enthusiasts, but I nevertheless just mention this in case somebody should have any interest of a copy of some details. The drawing is almost 1,60 meter and the quality is not great, so I guess I can only make copy of particularly required details.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 08 Jul , 2013, 10:57
Tore u're unique!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jul , 2013, 15:07
Hi Tore,
The drawing is almost 1,60 meter and the quality is not great, so I guess I can only make copy of particularly required details.


I'm one of those interested in seeing it as a whole :) If it is not possible I would like to see details related with main and auxiliary switchboards.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2013, 23:52
Hi Maciek.
I had an idea you are interested. I have made a few photos of the Schalt-tafel in the E-room as shown below to have an idea about the quality. May be we could go step by step in the same manner if you believe it is of interest. I shall try to stretch the paper a bit. I presume I did the colouring of the different lines way back in time.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2013, 09:35
Hi Tore,


this is my interpretation of one these drawings. Some of its elements are obvious, others not.
I have marked with blue ovals parts, which I can not recognize, but I would like to know what they are.
I'm confused about rotary converters. I have counted five - four (marked 2 - 5) look like single armature
converters and one (marked with 1 and labeled as Radio Sender) looks like double armature converter.
I'm trying to match these with informations from U-boat Information for U-boat Type VIIC (page 175)
http://uboatarchive.net/Manual.htm
but with no luck for now.


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2013, 09:43
On the second drawing I recognized two driving motors for two air fans (but which one is which - exhaust or intake - I do not know), and two motors for pumps - lubricating oil auxiliary pump and cooling water auxiliary pump - again - I do not now which one is which.
With blue ovals I have marked parts, which I do not recognize.


Tore, these drawings are great!


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 10:26
Maciek.

The upper blue oval shows, I presume, top motor for luboil purifier, under: seawaterheater for purifier and then  lower: dirty oil heater. The next smaller oval is electric heating ( heizung 4) and the lower circle heating ( heizung 3 ). I shall try to make photos a bit more systematic starting from aft and hope to be able to post it in the course of the week.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 11:51
Maciek
Here are the first photos starting from aft torp- E room .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 11:57
E- diagram
More photos, engineroom and galley and aft pto mess.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 12:01
E- diagram Controlroom
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 12:20
Maciek
Here are the final photos. It is all done in a hurry and I have not been able to check the details. If you are missing something just let me know.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2013, 15:09
Tore,
If you are missing something just let me know.


Thank you very much.
I wonder, if you could make photos of top parts of the pictures e1, e2, e4
and bottom parts of the pictures e3, e5, e7 and e8.
There is also some part missing between e2 and e3, e5 and e7.


--
Thanks, regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2013, 23:41
Maciek
Here are the top parts of e1 and e2
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2013, 00:03
Maciek.
Top photo e 4 galley
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2013, 00:35
The missing lower parts
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2013, 01:04
Maciek.
Final missing details. Again don`t hesitate to ask for more details if needed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 Jul , 2013, 06:15
Tore, thank you very much.


Could you help me to decipher some labels, marked with blue ovals?
Here are my few assumptions:
1 - something to connect test gear for G7e torpedoes
4 - heating panel for G7e torpedoes?
5 - something related with gyro-compass?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 10:44
eMaciek.
1. is marked as pruefgerat and connected to the switchpanel for light.
4. is marked as heiss-schaltkasten G7e
5. is marked as  E ? kompass.... Could be light for the gyro.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 10:48
maciek.
As to the electric system for the torpedoes you shall find a better quality of the text looking at the fwd. torpedoroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 Jul , 2013, 11:42
Thanks Tore,


and the others marks: 2, 3, 6, 7, 8, 9?


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 11:52
Maciek.
Coming up, harder to decipher, trying photoshop possibilities, but no success yet.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 12:30
Maciek.
I presume 2 and 3 are the rudders, 6 and 7 are the aft hydroplanes. If you look to the fwd. torpedoroom you shall find the same arrangement for the fwd hydroplanes. One type of the boxes are marked " Endlage...". I  believe the boxes are related to the operation system for hydroplanes and rudders. As you know they are all normally operated electric and having electric repeaters for position indicators as well. I assume the rudders and hydroplanes have main switches as drawn.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 12:50
Maciek.
9 is hard to decipher. It is a converter for the radiotransmitter, but the text is unreadable for me . I am posting a close up photo may be somebody can decipher the text.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 23:23
Maciek.
The 8 is a hard nut to crack. Below is a close up photo. I believe the first word is "Heissung..." but I cannot understand this as it is connected up to the aux. switchboard. Neither do I understand the type of switch placed in a wire from the aux switchboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2013, 23:41
Maciek.
Looking at the 5 which I assume is a similar indicator ligth system for the gyro, I believe I might see the letters G7e. Could 8 be indicator lights for the heating of the torpedoes?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Jul , 2013, 05:55
Tore, thanks.


I think, that 1 is for connecting some equipment for testing electric torpedoes. Why only in aft torpedo room? I have found, that there was low voltage motor testing gear, which consisted of acid-lead battery. I believe, that panel 1 was used to charging this battery.
2 - Endlageschalter - limit switch for electric motor driving main rudder
3 - Wiederstande - starting and breaking resistors for motor
4 - G7e Heizschaltkasten - G7e torpedoes heating panels
 5 - E komassumf (former) - rotary converter for gyro compass
6 - Wiederstande - starting and breaking resistors for aft diving planes motor
 7 - Endlageschalter - limit switch for aft diving planes motor
8 - something related with G7e torpedoes 
9 - Senderum (former) - rotary converter for radio transmitter


I will have more questions, when investigating remaining parts of drawing.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Aug , 2013, 01:22
The VIIC s surviving the Deadlight.
As far as I remember as a result of the Yalta conference in February 1945 US, Soviet and UK agreed to destroy the vast German submarine fleet leaving only 10 submarines for each of the three parties for research. The end story of all these 30 submarines is not known to me, but as we had a very close cooperation with British submarine services during the war ( 9Th. Submarine Flotilla) we assisted the RN as to the Deadlight transfer of the some 90 odd German submarines surrendering in Norway. The Norwegian submarine officers in the transfer commission came to the conclusion that some of the submarines were not fit for the transfer and they were temporary "stored" and "forgotten"in Norway.
After the cold war and NATO the transfer of these  submarines to the Norwegian Navy was formalised in 1950. Amongst these submarines were 3 VII Cs : U 324,U 926, U 1202 and one VIIC/41 U 995. U 324 was beyond repair and was used as a "sparepart boat", the reminding boats were included as frontline boats as the K class in the Norwegian Navy, got NATO pennant nos. and names of Norwegian light houses starting with a K. Contrary to what is stated these VII Cs were in the first years front lineboats and not training vessels.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Aug , 2013, 01:53
U 995
Of the VIICs surviving the Deadlight perhaps U995 is the most known. What might not be known is her last warpatrol. She was station in Narvik for operation against the convoys  in the Barents Sea. Feb. 45 She left for her last patrol (8. Unternehmung) under the commanding officer Hans Georg Hess being 21 years, the youngest CO of a submarine ever in WW2. At this time the Germans had withdrawn from the the Norwegian northern county  Finmark which was temporary occupied by the Soviet. In the Norwegian harbour of Kirkenes Hess discovered a Norwegian freighter estimated 6000 g.ts. (Idefjord) discharging cargo and he decided to attack. They were using tubes 1 and 3 which were loaded with FAT-2-Typ T IIIa ( Geleitzug) torpedoes. Hess observed two detonation and left a 3. shot to his No 1 Schroeder observing a 3rd hit. They reported the freighter sunk and Hess was awarded the Ritterkreutz over the radio. She fled the area hunted by the Norwegian corvette H. Nor.MS Eglantine. During the hunt Hess decided to fire the two last torpedoes, one bow and the aft at Eglantine, but at the crucial moment during the aiming, the Leitende Ing. Rudolph Wellnitz responsible for the trim and hydroplanes, dipped the boat and the periscope was submerged. Wellnitz was totally against  Hess about this attack so he dipped the boat. U 995 returned to Trondheim for retrofitting and Schnorchel installation where she still was at the surrender. Wellnitz, who possibly would get a death sentence, was not reported by Hess. Probably because he realized in aftermath that U 995 was saved due to this. Hess later became a lawyer and Dr. and took part in the restoration of the U-995 in Kiel. He died in 2008. The Norwegian freighter Idefjord did not get a hit and left later the harbour undamaged. The COs got probably the Ritterkreutz a bit more easy in the last months of WW2 . That`s the last warpatrol of U-995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 11 Aug , 2013, 05:04
Tore these are great pieces of information!!Thanks for sharing!!
So the torpedoes missed Idefjord. Any information about what they really hit or about the damage they caused?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Aug , 2013, 06:13
SG
There are a lot of discussion about where the torpedoes ended some search the near about rocks but no traces of a hit. A double short torpedonet (ex. German) was between Idefjord and U 995 but I understand experts said the torpedo would not detonate in the net. The only thing which is sure is that SS Idefjord left the harbour unharmed and Hess got his Ritterkreutz.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Aug , 2013, 08:32
U 995- at the end of the war.
A Norwegian enthusiast and hobby historian Otto H.Naesgard Andersen has written a couple of booklets dealing with the U 995 history during and after the WW2. " The torpedoattack on SS Idefjord" and " KNM Kaura ex.U 995 from Kriegsmarine via the Royal Norwegian Navy to museumboat". Unfortunately the publications, which are indeed very detailed, are in the Norwegian language but with the authors permission I am able to share some of the materials. Below I am posting two pictures of the U 995 crew at the commission Sept. 16 1943 and the last parole at the surrender May 1945 in Trondheim. As the author remarks you are able to see the crews relief having survived the war on the last picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Aug , 2013, 00:51
U 995 and the last warpatrol, attack on SS Idefjord.
Otto H. Naesgard Andersen gives a detailed description of the attack in his booklet. U 995 CO Hans Georg Hess called in his officers upon the sight of SSIdefjord in the Soviet controlled Norwegian harbour of Kirkenes and inspired by Guenter Priens Scapa Flow attack he said: "Meine herren, was halten Sie von einem Ueberraschungsangriff a la Scapa Flow?" in free translation: "Gentlemen what do you think about a surprise attack a la Scapa Flow?" They decided to attack February 8Th. and at night 0300 in silent mode put the boat on the sea bottom just outside a Soviet signalstation on the island of Rein
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Aug , 2013, 02:16
2.ND sinking of SS Idefjord.U 997
The story of Idefjord is very special. April 22ND. 1945 SS Idefjord was again on her way to Murmansk to join Convoy RA 66 back to Scotland. In the morning she was spotted by Oberleutnant Hans Lehmann CO of U 997 sistervessel of U 995. First torpedo missed and hit a soviet freighter "Onega" which sunk in a couple of minute, a second shot hit Idefjord fwd. port side, she did not sink and was towed to Murmansk. This convoy was again protected by the Norwegian corvet Eglantine and 4 minesweepers.
U 997 returned to Narvik and was due for fitting of Schnorchel exactly as U 995. Hans Lehmann got his Ritterkreutz as the last U boat CO as late as May 8Th. 1945.
Thus Idefjord contributed twice to Ritterkreutz award. Source: Otto H. Naesgard Andersen.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Aug , 2013, 23:24
U 995 and Idefjord epilogue.
As a finishing touch of this incident Otto H. Naesgard Andersen mention in his booklet autumn 1992 a Norwegian group of veteran naval gunners made a trip to U 995 at Laboe. Amongst these veterans was Bard Haugland a gunner on board the naval cutter Njal laying alongside Idefjord at the time of the attack and thus barely escaped sinking. They were met by Dr. Hans Georg Hess, the last German CO of  U 995, who acted as a guide on board. There was some mixed feeling in the beginning but in the end the meeting became very amicable. At that time a few photos were taken and I am posting below a  unique photo of Hess at the U 995 periscope in 1992 and a photo of Hess as a CO of U 995 at the bridge  ( source: Otto H Naesgard Andersen). 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 18 Aug , 2013, 04:53
 :)    :)    :)  ! ! !
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Sep , 2013, 11:42
Alberich.
An interesting question was raised by falo to Simon if the pressurehull was covered by the Alberich rubber assuming the wooden casingdeck did not to be covered. My Asdic knowledge has become a bit rusty since my Asdic training course, but I guess the WW2 Asdic was based on the piezoelectro effect of quartzcrystal which then was transmitting acoustic pulses which were reflected by any object on its way. The sound "ping" was made audible to the human ear by mixing the frequencies in the Asdicset.
I am by no means  an expert on the Albricht design, but I guess the pressurehull of a sub. is not the only surface which reflects the "ping",  every surface like the pressure hull, casing, casing deck and tower would give a reflection. I should presume in order to have a sound reflectiondamping like the Alberich synthetic rubber layer, you should encase the whole sub. hence having Alberich cover on the surface encasing the sub.
Having looked at photos of the U-480 you can indeed see the she is covered by Alberich layer  on the visible outer surfaces like pressurehull, casing and deck. The Asdic acoustic "pings" would be reflected by wood, thin steelplates (casing) as well as thick steelplates(pressurehull). Those parts like pipes, ducts, vents, valves and pressurehull inside the casing would be protected by the Alberich covered casing and deck.
At last, the Asdic reflection were very often disturbed by variation in the seawater salinity, temperatures etc. The submarines made use of this by launching a bubble decoy filled with magnesium pellets which reacted with the seawater creating  bubbles giving a sonar reflection like a submarine.
Again I am not an expert on this item so just take it as an airing of my view.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2013, 13:22
U 995 KNM Kaura
During the last couple of weeks I have been busy trying to paint a correct picture of the Norwegian version of U 995, KNM Kaura. The intention of the picture is to show her as a frontline submarine in the 1953 execution when I was the engineering officer on board. She is on her way to the Barents sea pitching in a stiff northerly breeze crossing the Vestfjord well above the Artic circle and meeting the old express steamer SS Finmark going south.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Sep , 2013, 13:32
Tore, that fantastic!!!!!!!

Are you up on deck, or down below, hard at work?  ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2013, 14:26
I am probably down below in my pink pyjamas
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Sep , 2013, 14:32
Standard Norwegian navy issue  ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2013, 14:49
Sure, I was wearing my old greasy navy cap as well. ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 01 Oct , 2013, 11:20
Tore, congrats for the outfit  ;D .. and for the great artwork!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Oct , 2013, 15:43
Next few pipes...

Pink = LO Cooler to Coll & Dist Manifold
Violet = Runs toward the pump (which I can not remember it name).
Green = from LO pump to pink line.
Yellow = from reducing valve to Green line.


(http://imageshack.us/a/img854/9346/new1ce.jpg)

(http://imageshack.us/a/img803/8096/new2z.jpg)

Hi Tore

Found a small mistake in the piping this morning. I had to realign the Starboard LO Cooler to Coll & Dist Manifold (Pink) line as it was going through the Cooling Water/Corrosion System pipe :o

(http://img819.imageshack.us/img819/15/e6fi.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2013, 08:06
Hi Simon!
Nice to have you back in action. I am not 100% sure I understand how the return from the luboil pressurecontrolvalve and the stb.luboilcooler got into the anticorrosion/ coolingwaterpipe on you previous drawing as I fail to see the hook up. A bit hard to see on a small cut out of the system I guess. Mixing luboil with coolingwater is of course no good. ;D
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Oct , 2013, 12:50
Hi Tore
 
Started drawing again a few days ago, it taken me this time to remember where I was on the drawing from last summer.
 
Hoping to finish the engine room this summer it will be my third summer on the engine room (18 months in total). I will not be able to spend as much time drawing this summer as I did last summer because I also need to work on my house and I just started a Masters Degree this winter.
 
I planning to finish the last few pipes in the top view, then redraw all the piping in the side view.

Had a very interest winter here in New Zealand, started with a huge snow storm which we got over 1.5 m of new snow in a few days. This resulted in a huge avalanche in my research area, I was able to got some great data :) The avalanche run a total distance of 1,984 m (6510 feet), cover an area 29.5 hectare (72.9 Acres) and had a mass of 50,686 tons. For the rest of the winter we got very little new snow :(

Now is springtime in New Zealand and we had more new snow in the last two weeks than we got for much of the winter, and it forecast to snow again this week ::)
 
Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2013, 13:09
Hi Simon.
While we are bracing for the snow and avalances after the best summer in 25 years you are entering the season for flowers and green grass, some difference. I shall be happy to follow you through the last part of the engineroom and look forward to seeing the final product which I  am sure shall be outstanding.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Oct , 2013, 13:32
While we are bracing for the snow and avalances after the best summer in 25 years...

We had the warmest winter in over 100 years in New Zealand this year...Global warming :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Oct , 2013, 13:36
Access panel?

(http://img19.imageshack.us/img19/7740/emz7.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2013, 02:00
Simon.
I don`t think this is an access cover. The area is the casing for the centrifugal governor and linkage having ample access by the large sidecovers. I am not 100% sure of what it is, some foundation placed in the centerline and right above the camshaft. I am inclined to believe it is some "residue" from the direct reversible execution shifting the camshaft when changing direction of rotation. As you know the direct reversible mechanisms are removed from the engines as from 1943, but some minor fittings were left on the engines. I am posting a few photos showing what I mean. An interesting detail of the stb engine is the governorlinkage coming out of the casing which you see differs from the port linkage. I might have mentioned it before, but the reason is that stb engine is the "mirror" execution of the port and hence the fuel rodlinkage has to move the opposite direction.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Oct , 2013, 21:53
Tore, here a better view of this area.

(http://img407.imageshack.us/img407/4500/tcd2.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Oct , 2013, 01:30
Simon a very good photo. I don`t think it is any foundation. I f you look at the aft end drawing of the starboard engine there is nothing fitted in this empty space and on your photo are only two nuts on two studs. It migth be the studs are the fixing of the support pedestal for the governor leverarm inside the linkagecasing, I guess you should only draw the two nuts/studs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Oct , 2013, 07:09
The situation for the German submarine fleet during the last days of WW2.
 During the last months of WW2 the center of gravity for the German submarinefleet moved to  Norwegian waters. A lot of confusion exist as to of the last months and weeks of the German WW2 submarinefleet. A RAF Air commodore (rtd) Derek Waller being an UK hobbyhistorian has carried out an interesting research on this subject and the time prior to the Deadlight. 87 U boats surrendered in Norwegian ports and further 9 from sea, making the total of 96 boats surrendering. His paper name these boats and they destiny, further he disclose the circumstances how France and Norway ended up with acquiring some of these boats in their submarine fleet. I have been in contact with Derek Waller and got his permission to share his recent paper on the subject which I trust shall have  interest for some of you.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 14 Oct , 2013, 09:20
Tore this is SUPER. Excellent piece of information, thanks for sharing!

U-4706: "Sold to the Royal Norwegian Yacht Club on 14 Apr 50". Fantastic  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Oct , 2013, 15:34
Tore, I am working on the Collecting Tank system. I have added the piping needed around the engines.

I have added two funnel under the Auxiliary Lubricating Oil Pump (as seen in the drawing) and one funnel under the Hand Lubricating Oil Pump (as seen in the drawing).

Where would you also want to collect FO and LO? Maybe under the 'new' LO Filter?

Thanks, Simon.

(http://imageshack.us/a/img819/5052/uuw6.jpg)
http://www.uboatarchive.net/U-570Plate9.htm (http://www.uboatarchive.net/U-570Plate9.htm)

(http://img19.imageshack.us/img19/619/fygb.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2013, 01:24
Simon.
Basically you should have a spillcollection tray or drain on any component handling fuel or luboil. However this is not 100% so. If we consentrate on the fuelsystem, plate U 570Plate 9 is showing the MAN system and not GW. The GW system has the fueltransfer pump up front of the engine and has a driptray under the pump with a drain to the fueloil collecting tank. On the U 995  there are for some reason two different fuel drainage systems on port and stb. engines. The engine top drainage  from the port engine ends in a collecting box on the camshaftcase, whereas on stb this box is removed and the pipes goes directly down under the floorplates to ,I presume, the fueloil collecting tank. The fueloil knifefilters on  the camshaftcases have driptrays with drain on both engines. The drains goes directly down under the floorplating and I presume to the fueloil collecting tank. Strangely enough the duplex fuelfilters up front of the engines have no driptray or drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2013, 01:54
Simon
Luboil drain.
We have no drawings of the luboil filters, but I should say  driptrays for the main luboil filters would be desireable. There are some problems though. The filters are well below the floorplating and as I should assume the drainage would go to the dirty luboiltank aft in the engineroom  it would be a problem with a gravity drainage to the tank. You could use the same dirty oil handpump on the aft engineroom bulkhead which is used for emptying the dirty oiltank. I`ll check if I can  see such a connection on some photos.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2013, 06:26
Simon.
I have checked with all the photos I have, but cannot for sure see any  connection on the dirty oil handpump for a possible drain. For the removed centrifuge module (encircled within the dotted red line) you see a pipe for dirty oilsludge from the centrifuge marked to the bilge, I don`t believe this end up directly in the bilge. When the oil centrifuge module was removed and substituted by filters, it could be they kept this pipe for the drain from the filter, however to have this confirmed without any drawing or photo would be difficult and it would still remained to be seen where it ends.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Oct , 2013, 12:54
I was thinking about linking the Auxiliary Lubricating Oil Pump funnel to the FO Collecting Tank

(http://img203.imageshack.us/img203/836/fpef.jpg)
You can see a small funnel next to the pump.

(http://img23.imageshack.us/img23/4514/tl6s.jpg)
I was thinking the piping might look something like this? What do you think?

(http://img59.imageshack.us/img59/5263/dd5q.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2013, 14:55
Simon.
The aux fueltransfer pump is a reserve luboil pump as well and when you change from fuel to lub oil and vice versa you have to drain the pipes and pump properly when you change. It could be the pump is drained through "k" via the funnel to the fuelcollecting tank or "k" are sniffers which are opened to let in air so fuel or luboil can be drained via the normal pipes to either in case of luboil to the luboil storagetank or in case of fuel to the fuelcollecting tank. I don`t think the pump has an ordinary driptray drainage. In any case I don't think the system is hooked up to the pressure side of the hoseconnection for the hand pump. I shall try to figure out something tomorrow as it is a bit late now ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2013, 02:09
Simon
The reserve luboil pump can be drained to the luboil storage tanks ( when bunkering luboil) as indicated on the below system sketch. In that case the cocks "k" act as sniffers e.g. letting air into the pump for easy drainage, I guess the drain would go OK by gravity. As a fueltransfer pump however I believe the fuel in the pump is drained via the two "k"s to the fuel collectiontank. In both modes the "k" pipes would go into the funnel you have indicated. The pipes from the funnel would end up in the fuel collecting tank. I don`t think there is a connection to the handpump. As to the luboil mainfilters I am in doubt, anyhow they should not be hooked up with the drainpipes from the "k" funnel as a filterdrain would probably be to low for gravity drain. I should leave a possible filterdrain at this point.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Oct , 2013, 12:56
(http://img823.imageshack.us/img823/9484/hj5e.jpg)

Tore, do these just drained into the bilge?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2013, 13:48
Simon.
 Fueltank compensating water drain.
The pipes you indicates are drain for the seawater for fuelcompensation and goes to the bilges.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Oct , 2013, 01:11
Tore,

New layout and I have added the missing piping for the Fuel Oil Compensating System.

On plate 10, the forward pipe from the tank, is it open to the sea?

The aft pipe from the tank, where does it go? Does it goto the muffler? Valve 'E' open to the sea?

http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)

(http://img585.imageshack.us/img585/3625/fh8p.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Oct , 2013, 02:14
Simon.
The forward pipe of the headertank is the outletpipe open to the sea. The aft pipe is the supplypipe from the exhaustcooling coming from the aft end of the silencer. Valve "e" is the draincock/valve of the exhaustpipe going to overboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Oct , 2013, 13:41
Tore,

In these three photo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Oct , 2013, 14:23
Simon.
I am not sure if these pipes are the drains from the headertank.
I should think the drain and the outlet from the headertank could basically be any place within the casing and I don`t see any particular reason for having the end of the pipe flush with the casing side. I don`t remember seeing water gushing out from the casing while the engines were running. I`ll have a closer look at my photos and let you know if I have any ideas.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2013, 00:24
Simon.
I have checked with all my photos and cannot find any confirmation of wateroutlet flush  with the casing side. I would suggest you place the outlet inside the casing and not flush with the casing side as long as we don`t have proper evidence otherwise.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 13:41
Simon.
I have checked with all my photos and cannot find any confirmation of wateroutlet flush  with the casing side. I would suggest you place the outlet inside the casing and not flush with the casing side as long as we don`t have proper evidence otherwise.
Tore

Tore,

I have decided to move the position of the piping for the Port and Starboard MB & RFO Tank 2.

I decided to move this section of piping because...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 14:03
If you used a 3-way valve like below and a handle you can open/closed the valve.

In the quick 3D drawing the pipe runs just under the decking and then steps down, the small deck hatch allow access to the valve, the straight through piping run even with the side casting surface, and the other pipe run to the side of the saddle tank.

(http://img708.imageshack.us/img708/3827/0d98.jpg)

(http://www.smgvalves.com/ckfinder/userfiles/images/products/permaseal/design_bw_3.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 14:10
I am able to shorter the piping by about 6 m :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2013, 14:16
Simon.
I guess this shall work  OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 14:35
Simon.
I guess this shall work  OK.
Tore

I started to more the piping for the Port and Starboard MB & RFO Tank 2 but the Blowing System for MB & RFO Tank 2 valves is in the way :-[

So, I will keep them in there original and just realign the piping a little :) 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 14:55
Simon.
I guess this shall work  OK.
Tore

I started to more the piping for the Port and Starboard MB & RFO Tank 2 but the Blowing System for MB & RFO Tank 2 valves is in the way :-[

So, I will keep them in there original and just realign the piping a little :)

Below you can see why there no room with the small Blowing System for MB & RFO Tank 2 valve deck hatch.
(http://img844.imageshack.us/img844/1671/de15.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Oct , 2013, 15:46
Tore,

New layout and I have added the missing piping for the Fuel Oil Compensating System.

On plate 10, the forward pipe from the tank, is it open to the sea?

The aft pipe from the tank, where does it go? Does it goto the muffler? Valve 'E' open to the sea?

http://www.uboatarchive.net/U-570Plate10.htm (http://www.uboatarchive.net/U-570Plate10.htm)

(http://img585.imageshack.us/img585/3625/fh8p.jpg)

New layout  :)
(http://img15.imageshack.us/img15/589/mkxf.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2013, 00:41
Simon.
Your new layout seems OK to me. I guess you have studied the space for the crossover up front of the conningtower there are a lot of stuff there.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Oct , 2013, 20:52
Simon.
The forward pipe of the headertank is the outletpipe open to the sea. The aft pipe is the supplypipe from the exhaustcooling coming from the aft end of the silencer. Valve "e" is the draincock/valve of the exhaustpipe going to overboard.
Tore

Tore, would the line going to the silencer look something like this?

(http://img201.imageshack.us/img201/7164/1rvp.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2013, 07:03
Simon.
I am not sure the connection to the silencer is OK. If you look at the sketch below it could be a bit more forward not to interfere with the drains.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2013, 12:25
Simon.
I am not sure the connection to the silencer is OK. If you look at the sketch below it could be a bit more forward not to interfere with the drains.
Tore

Just checking a few things:
Drain for the cooling water

Drains for the exhaust side

The pipe between the silencer and valve P is found on the under side?
What are the two arrows are the very aft end of the silencer?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2013, 14:55
Simon.
Good question which made me check with the system for the Man engine. There is a difference on plate 13 (GW engines) and 13A ( MAN engines). I can`t see there is any reason for having a difference on that particular part of the system. Plate 13 GW engines, mention "o" as water drainvalves (German: entwasseren) for exhausts side (German gasraum abgassammelltg.) plate 13A (MAN) names these valves as "p" waterdrain coolingwater space silencer (German: entwassern kuhlraum) there is no reason why these two valves are different. In spite of the plates tells otherwise I would suggest the two cocks on "o"are coolingwater vent cocks  placed on the top of the silencer, cock "n" is cooling waterdrain placed on the bottom lower part of the silencer. I should say two cocks make the venting a bit more efficient. 40 mm pipes seem OK. The drain empties the coolingwater space around the silencer. The two arrows at the very far end could be for possible pressure equalising when submerged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2013, 15:21
The two arrows at the very far end could be for possible pressure equalising when submerged.

So they would be just open holes in the silencer or a very short sections of pipes fix to the silencer?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2013, 00:19
Simon.
I guess unless we get other infos we asssume short pipes. If you look at plate 13 A and B you shall see these venting openings are drawn as coming from the exhaust side whereas on the plate 13 (GW engines) they are drawn from the coolingwaterspace. I should assume the latter is wrong and that the openings are acting more like the floodholes allowing the trapped exhaustgases to  escape.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2013, 00:32
Simon.
May be I should mention valve "e" on plate 10 which is a waterdrain for the compensating water supply line. As this line ends up halfway in the compensating water tank, the tank would not be emptied through this valve, hence a separate drain as indicated, however you got to have a valve which is not shown in this drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2013, 03:02
Simon.
Why all these elaborate exhaustgas ventings? If you consider the whole external exhaust system it represent a large volume. It certainly makes a big difference in weight (trim) if it is filled with gas or seawater. A possible trapped exhaustgas would upset the trim when diving hence I believe it would be necessary to have a proper venting of the exhaustgases to ensure all the gases escapes. If these ventings are not shut on the surface diesel propulsion you shall have of course exhaustgases escaping out of the vents.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2013, 09:57
Simon.
I have checked a bit further on the venting of the exhaustgas silencer and silencer valve. On the "O" class RN submarines they have a similar arrangement with no valves shown. So I  assume there are no valves in the venting and moderate amount of exhaustgases would escape possibly right above the silencer under the casing for both components.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2013, 05:06
 The Forum is back, very much appreciated. However it seems that about 12 pages and in excess of 150 posts have been lost in the crash, I guess it is not possible to retrieve the posts but I have of course the drawings if anybody are interested.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 13 Dec , 2013, 16:34
Tore, they exist but in a file that is "poison". It's not impossible to restore them, but difficult. The restoration just to this has cost us $$$, so I don't know if we'll be able to get them safely, but they are technically not lost! Apologies.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2013, 23:30
Thanks Wink. It is of course not worth the Money and risk to retrieve the posts. The basic materiel is available in my files. If anybody misses the last month posts let me know.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 14 Dec , 2013, 18:14
You're a treasure and a gentleman!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2013, 23:58
Season Greetings to all the friends in this forum.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 23 Dec , 2013, 12:32
Hello Tore,

Best wishes to you and I hope you are keeping well over in Norway.

Merry Christmas to everyone,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 23 Dec , 2013, 18:21
And to you, Tore. Thank you fr all your hard work and contributions here, it means a lot.

Stay warm!

Cheers,
Wink
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Dec , 2013, 20:06
Hi Tore

Here the latest drawing of the piping in the engine room.

Not going to be able to do any more drawing for the next month and a half :( :(

I am just too busy working on assignments for my bachelors degree. Hope to have some more free time near the end of February.

Merry Christmas everybody and a happy New Year
Simon

(http://img802.imageshack.us/img802/4514/z5do.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Dec , 2013, 06:31
Simon.
Very good. Your absence at the Forum matches very well with my plans as well. I shall be leaving for Africa within 3weeks and stay away for a month. looking forward to return end February.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Rokket on 26 Dec , 2013, 20:27
Good luck studying NZ (stop in and say howdy sometime) and good luck in Africa Tore!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Jan , 2014, 01:43
Simon.
Very good. Your absence at the Forum matches very well with my plans as well. I shall be leaving for Africa within 3weeks and stay away for a month. looking forward to return end February.
Tore

I see you are still alive and have not been eaten by a Lion ;)

Hope you having in a good break away, missing the snow yet  ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2014, 01:49
Simon
I am not yet there, leaving early next week taking my PC along, so if not eaten by a lion I shall be able to communicate ;D Snow keeps coming down forecast 0.5 meters this coming weekend
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Jan , 2014, 01:56
Tore, are you having a big winter so far at home? I heard they are having a hard winter in North America so far. The NZ summer here has been just average so far.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2014, 04:25
Simon.
 We really didn`t have much of a winter before last week, in our area -17C up in the mountains -37C. This week we got some 70 cm of dry fine white snow which makes everything brighter in the winterdarkness you get above 60 parallel. Time to join the birds of passage to Africa! ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2014, 14:44
VIICs mainengines.
As known to most of you the VIICs  were equipped with two mainengine alternatives, either MAN 6 M 40-46 or Krupp Germaniawerft F46A6P both had the same bore 400mm and stroke 460mm. The output and revs the same and the dimension appr. the same. The main outlook difference were to be found in the supercharging system. MAN was equipped with the so called Buchi system, an early version of the exhaust turbocharging and  GW had the Roots blower a mechanical driven supercharger clutched in at the manoeuvring place . I have seen quite a few kits for modelling the engineroom and the look of some of the engines in those kits are very strange. Down below is a sketch showing the different look of the two enginetypes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 06 Feb , 2014, 13:06
Hi Tore,
 
Great work, you are a fantastic asset to the forum.
a simple stupid question I hope, the upper and lower tower hatches.
Could they both be dogged/locked so that they could not be opened from above?
 
Regards,
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2014, 12:20
Hi Jon!
 Sorry I am a bit late in answering, but I am presently in Africa and was last week in some remote area with no Internet connection. I am now in Accra and are able to communicate. Your question is not at all stupid, as you might know today it is an international standard for opening the hatches and connect a rescuevessel to same. Re the last action for trying a rescueeffort on the Kursk. In the days of VIICs there was of course no such system, but all the hatches could be opened from outside by a handwheel see the drawing below of the lower towerhatch. On photo of the tower tophatch it looks as on the museum U 995 they have removed the top hatch wheel, however you can see the a small part of the stuffing box for the spindle in the center of the tophatch. Thus apart from removing the outside handwheel the cover could only be locked by a catch inside. That catch was merely used to release the overpressure in the sub and preventing the hatch to be flung open  which might have blown the CO overboard if the hatch was flung fully open.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 09 Feb , 2014, 12:29
Hi Tore,
 
thanks for the info.
 
Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2014, 12:35
Jon's questions on the hatches recalls my memories of the procedure for opening same after a long submerging, may be 30 hours or so. On a long time submerged situation everybody except people on watch, the CO and me was in bed using minimum of oxygen. The increased CO2 content in the air made everybody panting heavily. After a strenuous day it happened that an allowance of one cigarette per man was given ( crazy ) but mostly the match would not burn anyhow. When surfacing the CO on the top ladder having a man with a firm grip on his legs, carefully put the catch of the tophatch in position, turned the hatchwheel and the hatch cracked open letting the overpressure out so you felt it heavily on your eardrums. Mostly the foul air in the compartments turned into fog at the quick pressure release before the tophatch was fully open. The overpressure in the sub was due to various air leakages and inboard venting, but mostly by using the airmotor for the outboard group exhaustvalve grinders at the moment of diving.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2014, 01:30
Falo has sheared some of his excellent photos from the Laboe U 995 showing details of the present days condition of the U 995. As we have mentioned many times before the museum version of U 995 today should not be used as reference for a correct version of a  VIIC/41 and particularly not the original U 995. I shall try ( during some time) to give some comments as to the details partly based on Falos photos. Falos photo shows a very good detail of the Kingstons (Flutklappen) for main ballast tank 3. I have seen many strange modellers interpretation of these flapvalves one is shown on the picture below. The photo shows the Kingstons shut and the nuts of the seating is clearly visible.
As you see the Kingstones of mbt 3 opens outwards because when shut they are a part of the pressurehull in contradiction to the ballast saddle tanks 2 and 4 where the Kingstons opens inwards being not a part of the pressure hull and as the tanks are used as spare fueltanks as well. So if you want to make your model in a ready for sea execution the Kingstons of mbt 3 should be open and if there is fuel in the saddletanks the Kingstons of same should be shut otherwise open. By the way the Kingstons got the name after a British engineer Kingston who invented the valve, I guess latter part of 1890
The other item I shall mention in my post today is the propeller/rudderguard which is missing. In this area you should include zinc sacrificing elements, this detail is very often forgotten and is an element for corrosion protection. They should not be painted but have the zinc colour, see my picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2014, 12:24
In December 2012 we discussed the seawatercompensating of the saddle fueltanks, particularly the two positioned footvalve in the compensatingpipe connected either to the bottom of the saddletank or alternatively to a "compartment" directly in connection with the sea. We could not trace that "compartment". I believe Falos detailed photos have revealed the arrangement. If you see on the photo below it is a fairly large rectangular grating next to the Kingstons in port and starboard no2 and 4 saddletanks. As the very detailed photo shows the pipeopening behind the grating I believe this is the described "chamber"and the pipe is the direct seaconnection to the compensatingsystem.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2014, 05:10
Some of the photos sheared by Falo shows the peculiar "hullgutters" of the museum U 995. Where the sheet plating and the saddletank fairing joins the pressurehull there are some void spaces which collect rainwaters. This obviously created some problem for the museumspeople so they made drain cutouts in the plating and to prevent rustbleeding they welded a U-shaped steelbar as gutter, see photos below. This has nothing to do with the original design of the VIIC-VIIC/41s. Nevertheless I have seen modellers making painstaking copies of the gutters which have nothing to do on a VIIC model unless it is a model of the museum U-995 of course. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Mar , 2014, 04:36
Another of Falos detailed photos shows the "Pillenwerfer"slit and reveals a rare view of the outer cap of the ejector. The "Pillenwerfer" or ejector is a common device of a submarine. It is used for many purposes and is merely a steeltube having hinged caps in both ends and an interlock prevent the outer cap to be opened unless the inner cap is shut. The tube has a drain- and ejectingair connection. Inside is a piston having a guiderod through the inner cap. The ejector is charged with different types of canisters or signal rockets making possible for the submarine to send visible signals to the surface. A common canister used during WW2 was filled with magnesium pellets which was ejected when a submarine was Asdic hunted. As the canister was ejected the magnesium pellets came in contact with the seawater and the chemical reaction created a large amount of bubbles which gave a false echo on the Asdic. During exercises very often a signalrocket was ejected indicating a torpedo shot.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Mar , 2014, 14:56
Tore/Maciek

Oxygen system within engine room. Do you guys know:
Thanks, Simon.
http://www.uboatarchive.net/U-570Plate20.htm (http://www.uboatarchive.net/U-570Plate20.htm)
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Mar , 2014, 15:12
Tore/Maciek

Oxygen system within engine room. Do you guys know:
  • Where the manifold is located?
  • Where the Exhaust Air Duct is located?
  • Where are valves 'b' are located?
Thanks, Simon.
http://www.uboatarchive.net/U-570Plate20.htm (http://www.uboatarchive.net/U-570Plate20.htm)

I was able to find the Exhaust Air Duct on some drawing on the starboard side of the boat (can not find it in any photo's of U-995 :( ). This could suggest that valves 'b' are also on the starboard side of the boat.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Mar , 2014, 03:17
Simon,
exhaust air duct is on the port side of the boat. Forward 'b' valve is on the forward bulkhead, on the port side of hatch, near the upper edge of the door (with blue handle). The oxygen manifold is located in the aft starboard corner of engine room - over the clutch piston is visible water trap and manifold itself. Over the hatch to electric motor room are visible two thin lines - I believe they are lines to aft torpedo room and to forward part of the boat. There is also one large pressure gauge - I think it also belongs to this system. I was not able to locate aft 'b' valve.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 08 Mar , 2014, 06:20
Tore you said: "although it is shocking to see what they have done to my old boat". I suppose that I now comprehend what you mean. Please look at the attached pixs. The first shows a double-page, the printed pictures displays the boat during dropping on the two fundaments in the early seventies. If you look at the bow you can recognize the torp doors and the limber holes surrounding them. If you look at my pix (as said before from 2011 or 2012) the bow looks today very basic.

Regards
falo







Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2014, 09:55
Falo.
Yes , much have been changed and I don`t understand some of the changes, the flood gates are the fingerprints of the submarine. It would not make much of an extra to put in some floodgates, they have blanked off some floodgates instead as shown on your photo. On the other hand they have put up an extra wind deflector on the radar casing which never was there on any VIIC, that cost extra and they have removed the original exhaust outlet and put in a new instead, that cost extra as well. Why if funds are short?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Mar , 2014, 13:20
Simon,
exhaust air duct is on the port side of the boat. Forward 'b' valve is on the forward bulkhead, on the port side of hatch, near the upper edge of the door (with blue handle). The oxygen manifold is located in the aft starboard corner of engine room - over the clutch piston is visible water trap and manifold itself. Over the hatch to electric motor room are visible two thin lines - I believe they are lines to aft torpedo room and to forward part of the boat. There is also one large pressure gauge - I think it also belongs to this system. I was not able to locate aft 'b' valve.


--
Regards
Maciek

Thanks Maciek for the information.

Do you have any photo's of the exhaust air duct and the oxygen manifold, I don't seem to have any photo's of them :(

The oxygen line look like 10 mm? 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Mar , 2014, 15:34
Compartment ventilating and supply systems

I image we should look after the engine room crew ;)

Let take that bad air away :)

(http://farm4.staticflickr.com/3027/13019289113_521b09b016_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Mar , 2014, 15:56
Tore, what is that small hull opening right next to the vent valve, is it a drain line?

http://www.360cities.net/image/submarine-u-995-machine-room#2.39,-64.09,48.4 (http://www.360cities.net/image/submarine-u-995-machine-room#2.39,-64.09,48.4)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2014, 00:47
Simon.
Engineroom stand by and ready to get rid of that bad air. ;D. I assume your question concerns the ventilationshaft drain as indicated on the photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Mar , 2014, 04:42
Hi Simon,


1. Forward 'b' valve.
(http://s26.postimg.org/8iitig4qx/valve_b.jpg)


2. Water trap and control manifold
(http://s26.postimg.org/sytu0of0p/manifold.jpg)


(http://s26.postimg.org/mmeoqubyh/manifold2.jpg)


The manifold itself is the same as in forward torpedo room:
(http://s26.postimg.org/zf2sqrnk9/ftr.jpg)
Back to the two lines above the door to aft torpedo room - now I think, that one of them is oxygen supply line to air exhaust duct, second - maybe the line to aft torpdo room or to control room.


--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Mar , 2014, 15:19
Thanks Maciek

(http://farm8.staticflickr.com/7309/13043456995_55d0a9629b_o.jpg)


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Mar , 2014, 02:09
Tore, was the only way to get the dirty LO off the boat was a hand pump?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 10 Mar , 2014, 02:50
"Yes , much have been changed and I don`t understand some of the changes, the flood gates are the fingerprints of the submarine. It would not make much of an extra to put in some floodgates, they have blanked off some floodgates instead as shown on your photo. On the other hand they have put up an extra wind deflector on the radar casing which never was there on any VIIC, that cost extra and they have removed the original exhaust outlet and put in a new instead, that cost extra as well. Why if funds are short?
Tore"

__________________

I think further on money is very scarce but I agree they picked the wrong priorities. But some changes has a explanation: The blanked floodgates should stop those visitors of the boat who would like to climb on the wooden deck by using the floodgates as a "ladder". This concerns for example floodgates nearby the entrance and exit.

Thanks for your attached photos with the comments.

Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2014, 03:09
Falo.
Good to hear it is a rational explanation for the blanked off floodgates. Somebody has economical responsibilities for follies moving around, that`s probably why you have a grid shutting off the access to the tower. It is easy to forget she is now a museum allowing people to crawl all over, but why did they make a hinged manholecover easy to open on the saddletank as shown on the photo below?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 10 Mar , 2014, 04:44
"but why did the make a hinged manholecover easy to open on the saddletank as shown on the photo below?"

Tore, to be honest, I don't know and I have not an explanation for that. Again the manhole looks not very accurate. Maybe this hole stores the tools and paints for the preservation team? Just guessworking about that matter.
Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Mar , 2014, 00:38
Simon.
Dirty luboiltank pump.
The dirty luboiltank has no direct connection to an electric driven pump and normally you are only able to empty the tank by handpump. However the tank was originally connected to the purifier having both suctionpump and dischargepump connected to the tank. As you know the purifier was removed on the later version of the VIIC and VIIC/41`s.
The port and starboard luboil systems were normally operated separately. Thus in case you had a massive contamination of the oil, like emulsification due to watercontamination (it could happen), you emptied the relevant systemtank by the fueloil transferpump and did not use the dirty oiltank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Mar , 2014, 02:05
Simon.
Maybe the dirtyoil tank handpump system requires an explanation. I `ll take one of Falos fresh photos as a reference. The handpump has suction via 3 way cock A, either from port or stb. systemtanks and discharge to the hose connection via 3 way cock B. Cock B has a 3rd outlet to a funnel which goes to another 3 way cock C. Cock C has two more connections  to the suctionpipe of the pump and via the cock A either to the port or stb. systemtank and an another connection to the dirty oiltank. As there are no non return valves in the system you can either fill or empty the tanks via the hose connection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Mar , 2014, 20:04
Dirty Engine Lubricating Oil

One more system added to U-1308 :)

Piping = Violet - Blue - Violet

(http://farm4.staticflickr.com/3767/13095692793_1da076ab7a_o.jpg)

(http://farm4.staticflickr.com/3782/13095691173_b697a51c0c_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Mar , 2014, 01:44
Simon.
Seems to be OK. Some small details. As usual the wooden handle of the handpump is gone , may be you should put it in. There is a small suctionhose connection right underneath the suctioninlet of the pump. My uploadfolder is full so I cannot show much pictures I am trying to see if i`ll manage after deleting a few old photos. I am notifying Wink.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2014, 02:01
Hi Wink!
Just a test of my uploadfolder.
It seems to work! thanks Wink.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2014, 01:31
Hi Tore
 
You may have noted the number of engine room drawings has slow down. I been busy sorting out my Master’s Degree. I hope to get back to it soon.
 
Was hoping to finish the engine room this summer but that not going to happen :(

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2014, 12:03
Simon.
After all we are having fun with a hobby, your education is of course more important. In the meantime I have prepared some sketches which might put some light on further details particularly in the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Mar , 2014, 05:42
Simon.
Just keep busy with you studies and look into this whenever it suits you. :D I have gone a bit further into the fuelracks and governors of the main engines as your drawings have a few items missing on this system. May be you shall have a better understanding if I try to explain the working of the system. I start with the port engine as you know the starboard is a bit different. The basic is that the engineer is the overruling factor when he place the fuelhandle in the required position. If he want a higher revs he moves the handle so the fuelcontrol rod moves towards aft, turning the fuelpump plungers and thus increase the fuelinjection. The rod push the governor servo levers as shown on the sketch below, which means the servo piston goes down to a new fixed position and the whole linkagesystem turns around the fulcrum point A. The linkage (C )pulls down the servo slide admitting oil pressure to the top of the piston and drain underneath. At this position the new required revs is obtained and it is left to the governor to keep the revs stable. As the increased revs cause the centrifugal forces to move the weigths out thereby moving a sleeve and the connecting rod coming out of the camshaftcasing goes upwards. The rod is connected to a lever having a turning point at the servo pedestal which means the other end goes down and pulls A down. A is no longer a fixed point ( it has been shifted to B) and the servolinkage turns on fulcrum B.
This means the slide linkage point C goes down and the slide shut of the oil to the top of the piston and a new equilibrium  at the new higher revs has been established. The governor and servo shall "hunt" around this revs as the load varies. The lowering of the revs follows the same pattern in the opposite way. Just remember you first move the fulcrum B and then the system obtain balance at the new revs. by moving fulcrum A. How you are going to incorporate this on your drawing is not easy but as you see there are a few things missing. The linkage from governor lever to A ( adjustable) and one of the  two adjusting screws on the linkarm from servopiston to fuel controlrod.   
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2014, 03:04
Simon.
Governor linkage starboard engine.
As we have previously discussed the starboard engine is a mirrorexecution of the port except a few items. The fuelpumps and the governors are the same. In order to have the plunger inspection ( adjustment) window towards the aisle, the fuel pumps on starboard engine are turned 180 degrees meaning the fuelrack is moved opposite to the port engine. Thus for increasing the revs the rack moves forward. The governor servo is  the same as on port and not turned, and the linkage has to be different from the port linkage. For increasing the revs the fuelcontrol rod is moved forward (opposite to port) and  connected to the servo piston  via a trunnionshaft with levers to be able to connect the servo piston rod B which is  towards the centerline of the engine, the lever lift the servopiston to a new required revs position. At the same time the slide ( C) is lifted allowing oil pressue(red) to bottom of the servopiston and the whole leversystem is turning around A as the fulcrum. The increased fuelinjection rises the revs, the governor weights centrifugal forces lift the governor shaft coming out of the camshaft casing exactly as on port engine. As the servoslide connection point C is on the same side as the the governor rod you don` t need a balance lever as on port system, but only a supportarm hinged to the pedestal which means  (C) goes up ( opposite port) now using B as a fulcrum and an equilibrium   is obtained at the new fixed point B matching the required revs. I fully realize it there are a lot of links and levers but hopefully my sketch below having dozens of arrows  rather helps to explain and not confuse the system. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 25 Mar , 2014, 07:17
Hi Tore,
 
Sorry to distract you a little bit, but I have a question, if you don't mind.
 
It concerns the pressure hull.
 
When you served in the Kaurawas the pressure hull painted? if so. how often?
 
Regards
 
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2014, 08:02
 Jon.
At the time of KNM Kaura the pressurehull was divided in two, the part which was submerged while the submarine was surfaced and thus having barnacles and seaweed growth like a conventional ship.However the saddle tanks were painted black right up to the casing and that was an antifouling painting, approximately each 6 months depending on the growth , resistance and thus speedreduction. Then you had a complete painting of the outside, both pressurehull and casing each 2 years. The ballasttanks and especially ballasttank no. 3 were painted inside with a yellow!! ( yellow submarine? ;D) anticorrosive  zinc chromate simultaneously or if needed during the 6 monthly inspection. The wooden deck was constantly inspected and painted dark by crew, more for airplanes than need for protection. In fact the German regulations said always to have a dark paint for the wooden deck on board in view of the airsurveillance. The fancy wooden look deckpainting  which some modellers are using is thus not correct, a more dull dark gray almost black, would be more appropriate.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 26 Mar , 2014, 19:58
Hi Tore
 
Thank you very much for you answer, you have solved a couple mysteries that I have been wondering about.
 
Regards
 
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 29 Mar , 2014, 12:58
Tore, after a long time and lots of hard work, I think I have added all the piping under the decking forward of the engine :) :)


(https://farm4.staticflickr.com/3757/13492933913_aaeecbea7b_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2014, 00:36
Simon.
No doubt it is a lot of hard work behind this drawing. To have a complete picture of all the systems in a sideview is almost impossible, but after having a quick look it seems you got almost everything in place. Well done.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 31 Mar , 2014, 12:32
Tore i would like to ask you 2 questions about life in a type VII u-boat.
- Is it true that humidity and being wet were a constant issue? i mean how dry a crewmember would expect to be on a ordinary day? I've seen the scenes of Das Boot when people rushed back inside from the conning tower and the shower raining from the turret hatch was a constant matter. The film also shows food moulding. Was it all really like that or it used to happen only in long patrols or in particular circumstances, for example extremely bad weather?
- Diesel smell: confined to the engine room or soaking uniforms, berths, food?
thanks in advance
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2014, 14:06
SG.
First of all Das Boot gives an unprecedented image of the real life in a VIIC. Humidity was a problem. I never took my best uniform on board in spite we sometimes had to entertain guests and attend cocktailparties on fleetvisits abroad. All the stripes and buttons turned quickly green and the cloths got mouldy. For my own sake I solved the the problem in an illegal unconventional way by letting the first electrician installing a 40 watt bulb in my closet to keep my uniform dry. We never used the uniform at sea. This however was the fringe benefit of being the chief engineer and was of course never allowed to be installed for the rest of the crew. The lovely smell of diesel was not confined to the engineroom and I am afraid there was some concentration around my bunk and battledress not food,. ;D Apart from a few drops of water coming from the upper hatch just after surfacing during normal weathercondition it was dry. However in bad weather water would come gushing down like crazy and we very often had to shut the hatch leaving the poor buggars on the bridge to the elements. A few times we had to dive to continue sometimes you could feel the swell at 50 meters.(North Sea). Moulding of the food (bread)happened only during weeks of patrolling  like our longest schnorcheling trip of 28 days.
Tore


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 01 Apr , 2014, 06:18
Thank you very much Tore! the installation of the 40 W bulb was really a great idea!   ;D
Another question: Are the missions/patrols of KNM Kaura still classified? if not: what is the the most risky mission the Kaura has ever undertaken? 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2014, 08:04
SG.
I don`t think anything is classified, more history. Risky missions are not usually planned, they just happens for various reasons. The first risky mission was probably the first dive after being mothballed for several years after WW2. During the first years of the cold war and NATO we thought it would be OK to introduce the 3 VII Cs in our submarinefleet. The VII Cs were stowed away in a Norwegian fjord with very limited drawings and instruction material. The German navy did not exist, thus no possible German info. Old submariners got the job to figure out the details and I am told the first tests were carried out in the harbour of Trondheim with the biggest available harbour crane hook secured to the hull prior to the test dive. Incident occurred and risky situations ,not mission, arise. I have experienced two. During a work up period with fairly fresh crew we should carry out a routine dive and some how the main dieselair inletvalve was not shut, luckily the inletvalve into the engineroom was, but the whole airduct from the conningtower to the engine room was filled with water app. 5 tonnes, creating an unintended deep crash dive which didn`t stop till we were well below 100 meters. A similar situation occurred during a testdive after an annual docking. You always have an accurate weight calculation prior to such a dive to be sure you have the right ballast. No 1 being the responsible officer made a mistake and at the dive we went down like an elevator. The CO very quickly took action and ordered to blow all the tanks but we were so heavy so it took quite some time before we stopped at record depth where we were "hanging" some nervewrecking seconds before we slowly started to climb to the surface. However surfacing by blowing air and not using hydroplanes at depths exceeding 100m creates a jet effect by the expanding air and you shoot out of the surface like a torpedo and hope no surface vessels are in the neighbourhood. Other wise I was in charge of the longest schnorchel research mission ever at that time in our navy. 28 days submerged which I wouldn`t put in the category risky.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 01 Apr , 2014, 11:17
Amazing, am speechless and grateful for your willingness to share your 1st rate experience with us. By the way what was the record depth KNM Kaura ever reached? did the crew experience health problems secondary to reaching sudden depth during the uncontrolled crash dive followed by subsequent fast surfacing? I Imagine you tested silent running as well. Was it effective? was it double checked by surface units hunting for the Kaura?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 01 Apr , 2014, 11:54
Wow
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2014, 12:27
SG
KNM Kaura had a pressurehull damage in main ballasttank no 3, dents possibly by depthchargers. These dents were repaired by some extra frames but we were not 100% sure she could take the max designed diving depth. We never took her deeper that 125 meters in my time. We did not have any noticeable healthproblems due to incident like sudden uncontrolled crashdives. The procedure after such event was immediately to repeat the same thing, but off course under full control.
Silent running was a must. We had annually a test at the RN noise test station in Loch Goil near Bute Island, the submarine was semisubmerged and underwater microphones were surrounding the hull picking up each  possible noise we made. This was  the only time I was fully in charge of the sub. The CO and NO 1 were ashore watching the instruments and the engineers and electricians were starting and stopping each motor and component being a potential noisemaker. Each component had the noise registered and in the end you got a certificate for each component to be used under silent running condition. We got the exact picture of the noise we were making and it was indeed effective.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 01 Apr , 2014, 13:43
A good amount of great information! thank you so much Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Apr , 2014, 00:34
U 995 and present days execution.
Falo is finishing off his excellent photos of present days U 995 revealing the details of the externals. Apart from the previous comments I have a few remarks to modelbuilders.
As the German U 995 she  never operated as a schnorchel uboat. The schnorchel was installed March/April 1945. As a museumsboat she is equipped with a hinge float schnorchelmast, the original installed mast had a ringfloat. The schnorchel exhaust deck pipe and valve has been removed. The compass casing forward of conningtower was of the old streamlined type not the present days. For an Uboat serving in the Arctic I am not sure she has the right colour and the steel forecastle and poop deck is painted in a light blue-gray colour deviating very much from the dark wooden deck. A dark casingdeck all over was very important in view of the air-surveillance. As mentioned before , a wind deflector is fitted on the radarcasing, on the original U 995 it was not. The wind deflector on the rest of the tower was smooth rounded, not as today execution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Apr , 2014, 05:37
Following up my remarks on the colour of the wooden deck I post below a page containing a translated page of the instructions to the Uboat Commanders from the German high command revised 1943.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: 42rocker on 08 Apr , 2014, 06:37
A little of topic, but
A friend of mine translates and sells the M.Dv No. 906 - Geheim!  Handbuch für U-Bootskommandanten which is the manual in the above post. If you are interested in a copy see

http://www.germanmanuals.com/REmanuals.html

John does a good job on all of his manuals.

Thanks to everyone for such a great thread.

Later Tim
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 20 Apr , 2014, 15:23
Tore,
on this page there's a list of transmitters n receivers employed on u-boats:
http://www.uboatarchive.net/KTBNotesCommunications.htm (http://www.uboatarchive.net/KTBNotesCommunications.htm)
can you recall which ones (transmitter+receiver) among them were aboard the Kaura?
Had KNM Kaura the original german radio sets changed for some more updated post-war versions or still retained the original german radios?
Thanks a lot in advance and.. HAPPY EASTER!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Apr , 2014, 06:29
SG.
Sorry I have been off line for some 9 days and not able to respond. Unfortunately I don`t know anything about the radiotransmitter and receiver on the VIICs as it was not within my responsibility and usually the radiopeople wasn`t too happy to have any visitors. Generally our communication was fully intergrated in the Nato system and I should guess our equipment was adapted to that postwar system. During long voyages submerged we had to report at given hours by to a central Natostation Rugby by extreme longwave signals. We got signals as well from this station.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 25 Apr , 2014, 02:11
No worries Tore, i've been logged off for a few days too. Thanks for the information anyway, although incomplete it's undoubtedly a great piece of information!
Cheers
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 May , 2014, 12:26
Gentlemen,


I have been reading through the post on this site subject matter and I believe I can learn a great deal.  I may post questions later if you don't object to answering some basic questions about the Type VII C...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 May , 2014, 13:51
Don.
Shoot! Basic questions or not. I`ll be happy to answer if I can.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 May , 2014, 17:37
Hello Mr. Tore,


I am in the process of setting up the Skizzenbuch for the VIIC U-Boat in a 11 x 17 leather post binder.  I have the basic outline for the manual in MS Word.  However, I find it very difficult to read the schematics so graciously provided by Captain Jerry Mason on the uboatarchive.net web site.  It's almost impossible to determine pipe line colors on the black and white copies of the original German documents.  I don't know where I found Plate17 and Plate 27 that are a light tan color and you can see the color striping on the pipes.  In addition, you can tell that when a pipe crosses another that it is not a junction.  Does anyone know where the source for those documents came from and is it possible to get the full set.  I am only having "Staples" to print one copy for my own personal library and the leather post binder is very expensive ($230.00).


I understand the Negative Buoyancy Tank is vented internally through a muffler when it is being flooded in a surface maneuver.  Are there photos pointing to the control device (Valve) and the muffler in the control room?  I believe I would like to add photos of things like that to my Skizzenbuch. 


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2014, 00:41
Don.
I am not sure I fully understand your questions correctly. However most of the systemsketches provided on the net derive from the instructionmanuals of U 570 captured by the British in Iceland September 1941, thus the system sketches are not always 100% up to date with the executions of late war VIICs. The drawings are pretty much the same as we used onboard. However  some sketches have been coloured and adjusted by different people (crew?) and some mistakes are introduced. Thus there are no sketch valid for all the VIICs allthough basically the principal  system are the same. I suggest you chose which " VIIC vintage" you would go for and we discuss each system separately and hopefully I can answer your questions. In order to make it a bit simpler I answere your first question in a separate post.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2014, 01:35
Don.
Untertriebzelle system.
Yes, the venting mufflers and pipes  are fitted on the aft part of the attackperiscope casing. See photo below, a photo of the mufflers situated down in the bilge follows I just have to find it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2014, 02:12
Don.
I finally found one of  Falos execellent photos and put up a few arrows showing the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2014, 21:15
Hello Mr. Tore,
Thank you for the information and the photos...  The photo labeled Q Tank Muffler explains a lot and I have a few questions regarding that photo and Plate 7 from the Skizzenbuch.
The Negative Buoyancy Tank side of Plate 7
1.  There are 3 muffler (k) in the drawing on Plate 7
Q1 - Is there only 1 muffler as indicated in the Q Tank Muffler photo?
2.  Plate 7 shows 3 valves on the Negative Buoyancy vent line; a valve near each tank and one valve near the muffler (no glass viewing eye). 
However, the Q Tank Muffler Photo suggests there is a separate line from each Negative Buoyancy tank which has a valve and a glass viewing eye.  These two vent lines are joined at a “Y” connection and vent through the muffler into the internal pressure hull.
Q2.  Are my observations correct?
Q2-1.  On Plate 7, should the valve (h) going to the muffler (k) be a glass viewing eye instead of a valve?  This would make Plate 7 closer to the actual piping.  Unless there are actually 4 valves; 2 near the Negative Buoyancy tanks and 2 near the muffler?  The Plate 7 just doesn’t match the Q Tank Muffler photo… 
3.  The Q Tank Muffler photo has 4 valves and 4 glass viewing devices feeding into the one muffler.  I assume 2 lines for venting from Negative Buoyancy tanks and two lines for venting from the Regulating tanks and Bunkers. 

Q3.  Am I correct?

Q3-1.  Looking at the Q Tank Muffler photo  -  from left to right; which valve controls what?

Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2014, 21:24
Hello Mr. Tore,


One of the photos you sent was of Plate 17 and the lines to blow the Negative Buoyancy Tank.  However, when I look at the 2 different Plate 17 prints that I have there is a difference.  There is an extra valve going to the Negative buoyancy tank???


I will attempt to upload the two images later...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2014, 21:47
Here is the different Plate 17 with the extra valve at the Negative Buoyancy Tanks...


Opinion?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2014, 02:28
Hello Mr. Tore,
Thank you for the information and the photos...  The photo labeled Q Tank Muffler explains a lot and I have a few questions regarding that photo and Plate 7 from the Skizzenbuch.
The Negative Buoyancy Tank side of Plate 7
1.  There are 3 muffler (k) in the drawing on Plate 7
Q1 - Is there only 1 muffler as indicated in the Q Tank Muffler photo?
2.  Plate 7 shows 3 valves on the Negative Buoyancy vent line; a valve near each tank and one valve near the muffler (no glass viewing eye). 
However, the Q Tank Muffler Photo suggests there is a separate line from each Negative Buoyancy tank which has a valve and a glass viewing eye.  These two vent lines are joined at a “Y” connection and vent through the muffler into the internal pressure hull.
Q2.  Are my observations correct?
Q2-1.  On Plate 7, should the valve (h) going to the muffler (k) be a glass viewing eye instead of a valve?  This would make Plate 7 closer to the actual piping.  Unless there are actually 4 valves; 2 near the Negative Buoyancy tanks and 2 near the muffler?  The Plate 7 just doesn’t match the Q Tank Muffler photo… 
3.  The Q Tank Muffler photo has 4 valves and 4 glass viewing devices feeding into the one muffler.  I assume 2 lines for venting from Negative Buoyancy tanks and two lines for venting from the Regulating tanks and Bunkers. 

Q3.  Am I correct?

Q3-1.  Looking at the Q Tank Muffler photo  -  from left to right; which valve controls what?

Regards.
Don_

Don.
I am sorry to confuse you as I introduced the inboard venting and muffler for the FO regulating tanks 1 and 2 port and stb. This has nothing to do with the venting of the Untertriebtank. Thus a number of your questions are based on my mistake. I am afraid the venting of the Untertriebtank is  a bit more difficult to show on a photo, but as these tanks never are used for fuel there are no sightglasses, they have Kingstones and thus they have a pressure hullvalve ( valve near the tank). The Kingstones and vents are operated from the forward end of the CR and there is a common muffler  probably situated under the floorplates. I cannot recall the exact position of the Kingstones and inboard vent pipes, but have indicated on the photo were I believe they are. The Kingstones are operated by removable handles so you only see the valvestem. Back to the questions on the FO regelzelle. Contrary to the drawing the system is connected to one muffler. As to the sightglasses, only tanks which can carry fuel are equipped with sightglasses and the piping is slightly deviating from the drawing which is normal.  On the photo I have indicated my assumption of the system, if something is unclear just ask.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2014, 06:06
Don.
Blowingsystem of the Q-tank (neg. Tauchzelle).
The two system plans 17 and 17b are indeed different. The plan 17 system is using a dualsystem, the inboard venting pipe act as a blowingpipe as well, connectionbranch marked Drueckluftanschluss (pressure airconnection).  The connection to the Q tank is via an ordinary hullvalve. The system 17b has a separate blowingair pipe no connection to a ventingpipe and is entering the Q tank via a checkvalve and an ordinary hullvalve, eg. two valves. Plan 17b is new to me, do you happen to know the year it was made? I have a feeling it could be later than  1941. It should be a drawing of the inboard venting from the same year which give an better explanation of the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2014, 08:39
Don.
Further to my to days post I assume the arrangement for the Q tank venting-blowing on the U 995 is as follows. Your system 17b is a newer version of the plan 17 possibly introduced in 1943 and indeed installed on U 995. The piping is located forward part, port and starboard of the CR. On the photo below you`ll see the venting having a hullvalve and a second valve. On the photo of the stb hullvalve you `ll see they have exchanged the T handle with the inboard valvehandle a common thing on the museum U-995. The ventpipe on starboard goes up and cross over to port side  where it goes behind the electronic boxes and down to the muffler under the flooring. The port ventpipe goes down behind the the same boxes as well and joins the stb pipe prior to the muffler. Next to the ventpipe is the blowing air hullvalve, having a round handwheel with a ball. This valve has a checkvalve in the same housing as can been seen on the photo. To sum up, there are double hull ventingvalves on the ventingpipe,no connection to the blowingair pipe and a separate blowingpipe having a double hull valve of which one is a checkvalve.This should match very well with your systemsketch 17b and possibly for most of the VIICs built from 1943, so take your pick which vintage you`ll go for. ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2014, 09:11
Don.
In order to have a better overall picture I post two of Falos photos which shows the electronic boxes as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 May , 2014, 11:42
Hello Mr. Tore,


Thank you for all your time and effort in helping me understand the drawings.  If you don't mind; I believe I will use your method of overlaying actual photos on the Plate prints.  That's an excellent means to demonstrate a point and it will make my Skizzenbuck much more impressive to view...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2014, 12:53
Don.
I Guess the Q-tank system is not Complete without your indication of the Kingstones valvespindles which in some cases can be hard to localise. The Q-tank Kingstonespindles are the second spindles from forward bulkhead as shown on the photo below. As previously told the handles are cranks which are removed when not in use.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 May , 2014, 16:29
Hi Gentlemen,

Tore, I think, that the spindles you have marked on the photos are the drive shafts for the flood valves of the Tauchbunker 4. This topic was discussed here:
http://models.rokket.biz/index.php?topic=106.msg9585#msg9585

The valves you have marked are (in my opinion) for blowing Tauchbunker 4, getting fuel and sounding the tank.
Shaft drives of the Untertriebszelle flood valves are located further aft - near the attack periscope shaft (see the attached photos).

Regard to the hull valves of the Untertriebszelle - also see photo.
What do you think Tore?

--
Regards
Maciek

PS. Welcome to the forum, Don. You did not answer my email :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2014, 01:41
Don.
It is always good to have a watchdog like Maciek, particularly when you make a hasty conclusion like I did  in my eagerness to find a system matching you plate17b. Maciek is right, the Q tank is placed on both sides of frame 45 slightly ahead of the attack periscope casings centerline. Thanks for the correction Maciek, I was too quick. Maciek is introducing a solution to the Kingston which I believe is correct, further a blow/ venting solution which I am afraid would put your plan 17b on hold and back to good old plan 17.
You suggestion of the blowing/ venting of the Q tank seems to me to be correct Maciek. Some thoughts which backs up Macieks suggestion. Apart from the obvious placing of the Q, the use of same would indicate Macieks  arrangement suggestion is correct. Q is used as a quick diving tank which mostly is needed in emergency situations like crash dives avoiding ramming, collisions or depthcharging as such it has to be easy and quick to operate and placed close to the voicepipes. So I guess Macieks photo " untertriebzelle" is a good reference to use together with plan 17. As many times before together we find the correct solution ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 May , 2014, 10:43
Gentlemen,


I really appreciate all the help in locating photos of the Negative Buoyancy Tank control devices in the control room.  I found a photo on the internet which looks to be the Kingston valve wheel on the other side of the control room.  It looks to be the round black wheel, am I correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2014, 13:30
 ;Don.
This time I have doublechecked with the frames you can be sure this is the wheel for the port Q-tank Kingstone, you see the both on my bad photo below. I am still curious to know from where you got the plan 17b. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 May , 2014, 19:38
Hello Mr. Tore,


I wish I had a clue as to where I downloaded that Plate 17 (I renamed it because I had other Plates from the uboatarchice.net).  [size=78%]Today I looking into the functionality of the Main Pump and The Trim Pump.[/size]
[/size]
[/size][size=78%]The main Pump -  The manual states it's a reversible pump...  However, I seem to get everything to function properly with the pump running in one direction by utilizing different valves to provide pressure or suction.  Am I missing something?  I will post a photo of the mail pump and could you point out how the pump is reversed and why?[/size]
[/size]
[/size][size=78%]The Trim Pump -  I believe I understand how it works.  I will post a photo of the pump and could you post a good photo of the Trim Controller.  [/size]
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 May , 2014, 19:39
The Main Pump
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 May , 2014, 22:30
Tore,

regarding to the "plan 17b" - I was able to find its origin - it comes from "U Bootskunde für U Boote Bauart VII C", which translated version is published on uboatarchive.net - which was issued on 15 July 1940.

"Skizzenbuch fur das Maschinenpersponal" coming from U-570 and published on uboatarchive.net, which contains "plan 17" - was issued March/April 1941.

I think, that this explains differences.



Tore, there is one more thing, that makes me wonder. On the "plan 17" are marked four Druckunterschiedmessers - pressure differential gauges for the regulating tanks Regelbunker 1 Bb/Stb and Regelzelle 2 Bb/Stb. They show pressure differences between the external sea water pressure and inside the tanks - what is useful when fine flooding and blowing regulating tanks. Their are also used for operations described in Tauchvorschrift ( http://uboatarchive.net/DivingRegulations.htm (http://uboatarchive.net/DivingRegulations.htm) ) - paragraph 155, 163, 185

These four gauges are gathered on the control panel above the blowing ballast tank distributor (see photo - on both sides, in the middle - pressure gauge of the main blowing valve).

In the control room of U-995 are two more differential pressure gauges - near Untertriebszelle blowing lines' hull valves. These gauges are not drawn on the "plan 17", but are mentioned in the British report on HMS Graph (table on the page 39 - http://uboatarchive.net/U-570BritishReport.htm (http://uboatarchive.net/U-570BritishReport.htm) ). 

The purpose for these gauges I have found also in Tauchvorschrift - paragraphs 131 - 133.

Reading these paragraphs I'm wondering about "residual water check" (Restwasserprufen). It became obvious to me, that main problem while blowing Untertriebszelle is to stop blowing just before they are emptied - to avoid escaping of compressed air bubbles through the bottom flood valves. For this reason, the residual water check lines were applied. But I can not imagine how they worked. Could you put some light on this topic Tore?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 May , 2014, 23:10
The main Pump -  The manual states it's a reversible pump...  However, I seem to get everything to function properly with the pump running in one direction by utilizing different valves to provide pressure or suction.  Am I missing something?  I will post a photo of the mail pump and could you point out how the pump is reversed and why?


Well, in the original text the term is: "selbstansaugende, umschaltbare 2-stufige Kreiselpumpe". I translated umschaltbare as reversible, but it rather should be switchable. Switchable - that means that pump's two stages can be connected parallel or in series - for great capacity and low head or low capacity and high head respectively. The switching took place by control valve.

The Trim Pump -  I believe I understand how it works.  I will post a photo of the pump and could you post a good photo of the Trim Controller.


I have attached photo of trim controller.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2014, 02:18
Maciek.
Thanks for you spotting of the source for plan 17b.
Your observation on the differential manometer is correct. I assume the following: The local placed differential manometers for the Q is required for a good monitoring of the diff pressure not exceeding 2 bar. being the max allowing diff pressure. The normal procedure for using Q is, if you have time, to open the Kingstons (and inboard venting) filling the tanks while surfaced, then you are about in excess of 4 tonnes heavier than normal surface condition. In the event of crashdiving, you open the normal ballastvents, this Q weight speeds up going through the surface and at about 10 meters the hydroplanes and trim of the submarine take over the further diving. Depending upon the diving angle, E-motorspeed (and depth) the order blow Q is given and Q is blown by a diffpressure below 2 bar. The water residue checksystem is a small pipe going down to the Kingstons and an internal cock in the CR ending into a small funnel, I believe you can see same on the photo of the port system. At the blowing of the Q the testcock is open and seawater is pressed out until the waterlevel is slightly above the Kingston openings, then the blowingair enter the residuewater testline before it reach the Kingston opening, air comes out of the testcock and the order stop blowing Q is given, and the Kingstons are shut. Sometimes both tanks are not emptied at the same time and you have to shut the blowing hull valve of the empty tank before the other, that is one of the reasons you have two separate "controlstations" for the Q. I have tried to make a sketch showing how I assume the system works. I hope I have understood your question correctly.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2014, 02:36
The main Pump -  The manual states it's a reversible pump...  However, I seem to get everything to function properly with the pump running in one direction by utilizing different valves to provide pressure or suction.  Am I missing something?  I will post a photo of the mail pump and could you point out how the pump is reversed and why?


Well, in the original text the term is: "selbstansaugende, umschaltbare 2-stufige Kreiselpumpe". I translated umschaltbare as reversible, but it rather should be switchable. Switchable - that means that pump's two stages can be connected parallel or in series - for great capacity and low head or low capacity and high head respectively. The switching took place by control valve.

The Trim Pump -  I believe I understand how it works.  I will post a photo of the pump and could you post a good photo of the Trim Controller.


I have attached photo of trim controller.

--
Regards
Maciek
Maciek
Trimpump.
You are of course right. As a further comment to this pump, the trimcontroller was very much in use. Prior to shifting of some weighs inside the submarine you pumped water from forward to aft or the opposite. One of the most used order from the officer on watch was: pump 400 liter from aft to forward, then you knew it would be followed by : diving station!. It happened people were on their station before the latter order was given. The weightransfer was necessary as quite a few people lived in the fwd torpedocompartment and had their divingstations in the CR. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2014, 08:58
Don.
I don`t know if you got the working of the "Trimschalter" OK so I made a sketch showing how it works in the trimpumping mode, ballastwater from forward tank to aft and the opposite. Please note that the trimpump is a piston pump, the airvessels can be clearly seen in the front, whereas  the main bilgepump is a two impellers centrifugal pump where the impellers can either be run in series or parallel as Macieck says.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2014, 12:08
Hello Maciek,


I looked at the photo closely and it looks like there are 5 pressure gauges (one under the red hand wheel) clustered around the main blowing valve.  Would that be a pressure gauge for each dive tank 1 through 5?

In addition, on your photo labeled "untertriebszelle gauges"  The large red hand-wheel is for one or both Negative Buoyancy tanks?  I don't see the same configuration on the other side...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 May , 2014, 13:06
I looked at the photo closely and it looks like there are 5 pressure gauges (one under the red hand wheel) clustered around the main blowing valve.  Would that be a pressure gauge for each dive tank 1 through 5?

There are five gauges - the one on the top/in the middle is the pressure gauge in blowing distributor, the other four - two on each side are the pressure differential gaueges for Regelzelle Bb, Regelzelle Stb, Regelbunker Bb and Regelbunker Stb. See photo.

In addition, on your photo labeled "untertriebszelle gauges"  The large red hand-wheel is for one or both Negative Buoyancy tanks?  I don't see the same configuration on the other side...

The large red wheel is hand regulating valve for both tanks. See photo.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 May , 2014, 15:48
Hi Tore,

thank you for your answer - that was exactly what I wanted to know.

The water residue checksystem is a small pipe going down to the Kingstons and an internal cock in the CR ending into a small funnel, I believe you can see same on the photo of the port system.

Are you thinking about this line? I have marked this with green color.
I also marked lines which (if I'm not mistaken) fed differential pressure gague for Untertriebszelle Bb. The red one connects with Untertriebszelle Bb, while the blue one - with outside sea.
Unfortunately I was not able to find good photo with some cock/valve visible, which would cut off the residual water check line from the negative tank.

--
Regards
Maciek

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2014, 21:27
Hello Meciek,


Would this drawing be correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2014, 00:54
Hi Tore,

thank you for your answer - that was exactly what I wanted to know.

The water residue checksystem is a small pipe going down to the Kingstons and an internal cock in the CR ending into a small funnel, I believe you can see same on the photo of the port system.

Are you thinking about this line? I have marked this with green color.
I also marked lines which (if I'm not mistaken) fed differential pressure gague for Untertriebszelle Bb. The red one connects with Untertriebszelle Bb, while the blue one - with outside sea.
Unfortunately I was not able to find good photo with some cock/valve visible, which would cut off the residual water check line from the negative tank.

--
Regards
Maciek

--
Regards
Maciek
Hi Maciek.
Yes your green line could be the residual water checkpipe. The checkvalve might be situated further up as indicated on my photo below. I am not sure about your assumption for the diff manometerpipes though. As you see from my photo it looks as if both  pipes goes only to the manometer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2014, 11:09
Hello Meciek,


Would this drawing be correct?


Regards,
Don_
Don.
I am not sure, as the  two systems blowing and venting is combined in one on board, this can be confusing as on plate 17 and 7 they are drawn as separate system see my photo below. The blowing system on plate 17 starts with the blowing valve (hand control valve) having air supply from the main distribution manifold. After this valve is the reliefvalve, a manometer connection and a drain. This is a standard package for all the airblowing system. After this system is a shut off valve. It seems to me as you have switched  the hand control valve to this shut off valve. When the drawing and the real world is not corresponding it is usually best to follow the real world. It is almost impossible to check the system locally based on the photos we have available, however we can not see any plain manometer, but clearly a differential manometer which we can assume is hooked up as on the visible port side, the reliefvalve is visible so that is OK. The shut off valve I cannot see but I am almost sure it is there together with the connection to what I would call the common venting/blowing pipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2014, 12:07
Hi Meciek,


Thanks for the quick response....  I did a little art work to enhance the previous photo.  Does it look OK?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2014, 12:44
Don
Not bad. If you follow the port ventpipe down it disappears behind a small steel cabinet right underneath i the pipe ends in a fairly large Box which I believe is the  venting muffler for the two Q tanks, see the bad photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2014, 14:01
Don.
As a final touch I should probably mention that I believe the external floodvalve for Q is  not a  Kingston, square flapvalve, as on the fuel/ ballast saddletanks 4 and 2, but rather a valve behind a large square grating next to the aft Kingston on ballasttanks 4 port and stb. On the photo below you can see what I assume, my first thoughts were that this grating was connected to the fuel compensatingsystem but I believe the above is a better theory, you can see the round valve outlet behind the grating. Thus I suggest you rename floodvalve driveshaft: Handwheel external floodvalve . As a curiosity I have found out that the flood area of these valves are 0.24 m3 and with Q fully blown you have a residue water in the tanks of 0,16m3, not much. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 May , 2014, 14:56
Hi Tore,
Yes your green line could be the residual water checkpipe. The checkvalve might be situated further up as indicated on my photo below. I am not sure about your assumption for the diff manometerpipes though. As you see from my photo it looks as if both  pipes goes only to the manometer.
Thanks for your answer, I think you are right. I did not recognize relief valve.
I am not sure, as the  two systems blowing and venting is combined in one on board, this can be confusing as on plate 17 and 7 they are drawn as separate system see my photo below. The blowing system on plate 17 starts with the blowing valve (hand control valve) having air supply from the main distribution manifold. After this valve is the reliefvalve, a manometer connection and a drain. This is a standard package for all the airblowing system. After this system is a shut off valve. It seems to me as you have switched  the hand control valve to this shut off valve. When the drawing and the real world is not corresponding it is usually best to follow the real world. It is almost impossible to check the system locally based on the photos we have available, however we can not see any plain manometer, but clearly a differential manometer which we can assume is hooked up as on the visible port side, the reliefvalve is visible so that is OK. The shut off valve I cannot see but I am almost sure it is there together with the connection to what I would call the common venting/blowing pipe.

Tore, do you think, that relief valve is on the port side? Could you point, what you call the common venting/blowing line?
As a final touch I should probably mention that I believe the external floodvalve for Q is  not a  Kingston, square flapvalve, as on the fuel/ ballast saddletanks 4 and 2, but rather a valve behind a large square grating next to the aft Kingston on ballasttanks 4 port and stb. On the photo below you can see what I assume, my first thoughts were that this grating was connected to the fuel compensatingsystem but I believe the above is a better theory, you can see the round valve outlet behind the grating. Thus I suggest you rename floodvalve driveshaft: Handwheel external floodvalve . As a curiosity I have found out that the flood area of these valves are 0.24 m3 and with Q fully blown you have a residue water in the tanks of 0,16m3, not much.

I think you are close with your assumptions. I believe that description of the negative tank's flood valves in the type IXC report can be helpful:
Quote
The negative tank flood valve is a mushroom valve opening outboard.  The valve disc is provided with a screw thread, and is raised or lowered by rotating the valve spindle which is threaded into the stem portion of the disc casting.  The spindle is fitted with a collar and ball bearings to serve as a carrier for the vent valve disc.  When turning the spindle, guides prevent the disc from turning.  The valve is operated by means of a hand crank from within the vessel.
http://uboatarchive.net/DesignStudiesTypeIXC.htm


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2014, 19:10
Gentlemen,


Just how many people were required to be in the Control Room on a dive?


1 - Captian
2 - Chief Engineer
3 - Navigator
4 - 2 x Plainsmen
5 - Rudderman
6 - 2 x Q tanks (Port & Stb)
7 - 2 x saddle tanks (D2) Port & stb
8 - 2 x saddle tanks (D4) Port & stb
9 - 1 control D1
10 - 1 control D3
11 - 1 control D5


I count 15 people; it sure looks crowded to me.  Then again, on a crash dive you have people attempting to get to the bow of the U-boat.  They sure could use a computer system with sequenced controlled servos to do all those manual functions!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2014, 21:11
Hello Mr. Tore and Maciek,


I read your comments about the Negative Buoyancy tank and the different valve system.  I made some changes to Mr. Tore's drawing.  What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2014, 22:28
Hello Mr. Tore,


"the flood area of these valves are 0.24 m3 and with Q fully blown you have a residue water in the tanks of 0,16m3, not much."

Should the flooding area of the valves be 0.24 m2 (square meters and not cubic meters)?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 00:00
Maciek.
Thanks for your finding of the description of the Q floodingvalve as executed an a IX C I think it could be approximately similar to a VIIC.
Normally you would have a reliefvalve close to each tank as a protection of the tank, so I Guess stb Q would be the same as port. Common venting/blowingline is simply the two crossover pipes on plate 7 and 17 merged in one pipe see photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 00:07
 ;DHi Don.
You are of course right, the floodarea should be in m2 not m3, my old stiff finger hit the adjacent 3 without my notice. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 00:31
Don.
I Guess manning of the controlroom varies. On your list you have missed a few. The most important man would be the NO 1 the officer second in comand of the CO, CR engineer, a petty officer who amongst other jobs is in charge of the blowingdistribution panel, thus blowing the tanks, the trim/pumpman, the chief electrician and then the torpedo officer only to mention a few in addition to your list.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2014, 01:37
Hi Gentlemen,

the number of the crew in the Control Room (as well as in other rooms) were determined by so called Rollentafeln. They were divided into two parts: seemännisch (nautical) and technisch. Each part described function of the crew member in every condition (that means Klarmachen zum Tauchen, Friedens Tauchstation, Kriegsmarsch, Freiwache, Gefechtstation, Artillerie Gefechtstation, Boje über Board, Manöver). In Kriegsmarsch condition, during dive, in Control Room there are following persons:
- forward dive plane operator
- aft dive plane operator
- vent of ballast tank 5 operator
- negative tanks stb operator
- negative tanks port operator
- vent of ballast tank 3 stb operator (also ballast tanks 2 and 4 stb when used - they were fitted with common vent)
- vent of ballast tank 3 port operator (also ballast tanks 2 and 4 port when used - they were fitted with common vent)

As the ballast tank 1 according to regulations had to be vented as last one, the vent valve could be operated by one of persons mentioned before.
Also there were persons mentioned by Tore - commanding officer (or officer of the watch), chief engineer, torpedo officer.
I believe, that blowing distributor, trim station or pump operator roles were performed by some of persons listed above.

Generally, Tore has interesting experience from the Norwegian service of U-995.

- main rudder operator was in conning tower (rudder station in control room was kind of emergency one. Although Tore said some time ago, that when KMN Kaura  was in service, the common practice was to use control room station, as it was more convenient while snorkeling)

Generally, it seems, that in control room should be much about 10 people. For comparison - on type IXC U-Boats:
Quote
When surfaced, there are five persons in the control room.  At battle stations, there are ten.
http://uboatarchive.net/DesignStudiesTypeIXC.htm

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 01:56
Don.
Your adjustment of my system sketch seems to be fine to me. If you study the original German plates you`ll see on the system sketch a 90 degrees gearcone arrangement inside the Q tank, if we assume this is right we should add same, further you valveopening seems to be a bit to large, I believe each of the nearby MBT4 Kingstons has a flood area of 0,9m2 whereas the total Q floodvalve area is 0,24 m2 for a comparison. The red dot on the photo of the grating indicates the diameter of the floodvalve inlet.
Do you have any particular reason for introducing a U bend at the end of the checkpipe? You would of course get an earlier warning but you`ll leave more residual water in the tank, but you could obtain same with the length adjustment of the pipe. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 02:53
Don.
Manning of the CR.
Maciek gave a good information of the German manning regulation, my info was based on RN and Norwegian regulation. Basically Maciek reference to the German regulation are the same, manning varies with the type of diving stations f.i.. it is a big difference with a routine surfacing while the crew are sleeping and at a battlestation situation, so it varies. The system of splitting the  crew into navigational (deck) and technical crew is normal in most navies I think. Our system was based on the RN system as our navy fought in UK exile during WW2 and our submarines were English and training was done in UK. I my shelf was trained in UK. The big difference is that in the German navy the chief engineer was responsible for the trim, ballast calculation and in command of the hydroplanes etc. In the RN and many other navies including ours this job is done by the NO1, next in command of the CO.
The chief engineer is mostly stand by if something should go wrong and engineers would be required. During battlestation in our navy however, the chief engineer worked with the CO with distance bearing/ calculation. Down below is a picture with the CO on his knees at the navigation periscope and I calculating the distances during a dummy attack just to give you an idea.
When using the attack periscope the chief engineer was not in the tower but in the CR. At the attackperiscope the CO could get a lot of info directly, however we did not trust the German fruitmachine so the CE had to do some calculation passing messages up to the tower verbally. So you see Don, as so many times before, it is not a single answer to a simple question. :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 14 May , 2014, 03:29
It's good to see you at work  8) . Also, Great info Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 06:00
Don.
Manning of the Control room.
May be a further explanation why it is a difference in the German and RN ( and other navies)  manning regulations. The VIICs was, as known to all of you, equipped with manually operated ballastvents operated by rods and levers that required a lot of People locally placed. The RN and many other navies operated boats having hydraulically (Oleo system) operated vents which were controlled  by one person, like the blowing of the tanks at one station, that saved a lot of personell, thus a reduction of the people in the CR. The CR engineer was responsible for both the HP airsystem and the hydraulic system and would take an experienced PO engineer to handle and maintain. He was indeed an important man.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2014, 06:12
Hi SG
The photo was made by a paper making a report about life on board a submarine, we were warned on beforehand, that`s why I was wearing an uniform with even a white shirt. We newer wore this at sea, as previously told my favourite dress was a pink pyjamas often covered by a greasy battledress and mostly my uniformcap . ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2014, 13:10
Hello Mr. Tore,


Would this be correct for the locations of the Q tank valve and drain funnel for testing an empty condition on the Stb. side?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 May , 2014, 15:38
Hi SG
The photo was made by a paper making a report about life on board a submarine, we were warned on beforehand, that`s why I was wearing an uniform with even a white shirt. We newer wore this at sea, as previously told my favourite dress was a pink pyjamas often covered by a greasy battledress and mostly my uniformcap . ;D
Tore

WOW... I was starting to think that the RNoN had a very high standard of dress code on there submarine ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 14 May , 2014, 23:48
Tore, now you must show us a pic of you at  work in your (in)famous outfit !!!!   ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2014, 01:24
Don.
Residue watercheck Q stb.
Your picture (green oval) seems to me as being the possible relief valve of stb.Q, Your green pipe could be the part of the residue water check pipe ending up in the funnel, sometimes these small pipes are bended and twisted. The pipe looks a bit small. I have made a picture suggesting my ideas, the reliefvalve is a bit doubtful as I cannot see the reliefvalve of the HP air distribution manifold. If you would check further please note: There are two pipes going through the hull near the blow/vent hullpipe, these pipes join in a greasenipple for greasing the external floodvalve so you don`t get confused by these pipes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2014, 02:44
Simon and SG.
Oh you guys! :D Don't forget we were 46 men who shared 2 small handwashing basins with no facilities for washing clothes and we could be submerged for up to a month. The VIICs were not fit for a prolonged submerged time as schnorcheling, so you were wearing your clothes until you almost could throw them away rather than bringing them back home. Thank god I have no photo of my pink pyjamas, however I Guess I have a photo of us coming straight from the North Sea dress as we used to be. I`ll see if I can find the photo some day ;).
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2014, 07:41
Don
Residue water check Q stb.
I have rechecked the available photos and have made an additional picture putting up my final findings. My assumptions are: Q reliefvalve OK.greasing pipes OK.Q blowing manometer is missing only bracket left, diff manometer OK.residuetest line funnel OK, residue hullvalve having round wheel marked and OK. some of the piping can be seen but missing all the way to the funnel. I have posted a photo with the additional info. Thus I guess the picture should be complete as I see it today. As we know the 4 blowing manifold diff manometers have a single common reference pipe to the sea, I believe the Q diffmanometers are hooked up to same as well, although not shown on any drawing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 May , 2014, 08:55
Hello Mr. Tore,


I was reviewing Plate 16 and I don't understand why there is an extra set of mushroom vent valves towards the back of Dive Tank 2 (D2) in the saddle tank area.  I circled the valves in question in red.  Does it have something to do with diving since the valves are towards the back of the saddle tanks?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2014, 09:24
Don
The vents are the residual airvents which are needed for the aft saddle ballast tanks because you dive with a bow down angle. By doing that air is trapped in the aft part of the tank and you need to get rid of that air by extra vents. They are operated from the engine room. For the same reason you don`t have this arrangement for the fwd. saddle ballast tanks 4 port and starboard as here the mainvents are at the aft end of the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 May , 2014, 18:44
Hello Mr. Tore,


This is a long multi-part question with reference to Plate 16 and Plate 17...


Is the Regulating and RFO tank 1 open to the Sea?  A while back I had the understanding that this tank had fuel oil floating on top of water and as the oil was used it was replaced with Sea water (a Self Regulation tank).  If so, then where is the opening for the sea water to enter the regulating and RFO tank 1?


It looks like there are 3 blowing distributor systems
1.  the Main Blowing Distributor (Plate 17)
2.  the Exhaust Blowing Distributor (Plate 16)
3.  the Emergency Blowing Manifold (Plate 16 and Plate 17)


Q1.  is this correct. where are they located in the control room
Q2.  it looks like the Exhaust Blowing Distributor only affects D1 through- D5
Q3.  It looks like the other 2 blowing distributors affect all tanks except Regulating Tank 2 because this tank has no flood valve and has to be pumped???


If there is a down U-boat and a diver hooks up the two lines in order to bring the U-boat to the surface, then all effort is for nothing if no one is conscious and able to open the Tide valves on D2, D3 and D4, and open the hull valves on ALL the other tanks???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2014, 00:18
Don.
This was indeed many questions which all cannot be answered with yes or no. I post my answers in different posts starting the compensating tanks 1 and 2.
The purpose of the compensating tanks is to compensate for the changing the weigths of the submarine. The weigth is changing all the time, extra people are coming on board, fuel, freshwater and provision are consumed etc. Thus you have to compensate this by taking water in and out of the compensating tanks fairly often. Both the comp. saddletanks 1 and 2 have no direct contact with the sea, filling and pumping is done by connection to the bilge pumping system both for filling ( fine flood) and  emptying by the bilge pumps, see plate 6.
In order to further increase the reserve FO capacity a part of the compensating tanks are made as FO. reservetanks, called 1 port and stb.. The tanks are not always used as such. When RFO compensating tanks 1 port and stb are used as fuel oil tanks , the connection to the bilge system is shut and the tanks are connected to the fueloil system. See plate 9. If you have questions to the plates 6 and 9 shoot.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 16 May , 2014, 00:39
Don,

Is the Regulating and RFO tank 1 open to the Sea?  A while back I had the understanding that this tank had fuel oil floating on top of water and as the oil was used it was replaced with Sea water (a Self Regulation tank).  If so, then where is the opening for the sea water to enter the regulating and RFO tank 1?

Regulating and FRO Tank 1 (Regebunker 1) was not self-compensated tank. It was pressure-proof, flooded and emptied by means of the flooding and drain manifold (Flut und Lenzverteiler).


It looks like there are 3 blowing distributor systems
1.  the Main Blowing Distributor (Plate 17)
2.  the Exhaust Blowing Distributor (Plate 16)
3.  the Emergency Blowing Manifold (Plate 16 and Plate 17)


Q1.  is this correct. where are they located in the control room
Q2.  it looks like the Exhaust Blowing Distributor only affects D1 through- D5
Q3.  It looks like the other 2 blowing distributors affect all tanks except Regulating Tank 2 because this tank has no flood valve and has to be pumped???

Only main blowing manifold (compressed air) is located in the Control Room - right to the aft diving plane operator station.

The exhaust blowing manifold is outside the pressure hull - (more or less) over the main blowing manifold. Through the pressure hull are passing valve spindles, and only hand wheels are available for operation in the control room. These are eight, small, red hand wheels at the control room ceiling, over the main blowing manifold.

The emergency blowing manifold would be also located outside the pressure hull - in front of the conning tower, in the magnetic compass casing. Would be - because in late-war front going U-Boats it was not fitted (U-995 was not equipped with that). In the HMS Graph report this manifold is mentioned, but from survivors interrogation reports seems, that this manifold was fitted only for the time of U-Boat crew training (that is, when the vessel operated on the relative shallow waters of the Gdansk Bay or similiar).
Here is short discussion: http://models.rokket.biz/index.php?topic=921.msg12001#msg12001 (http://models.rokket.biz/index.php?topic=921.msg12001#msg12001)

The exhaust blowing manifold indeed affects only ballast tanks.


If there is a down U-boat and a diver hooks up the two lines in order to bring the U-boat to the surface, then all effort is for nothing if no one is conscious and able to open the Tide valves on D2, D3 and D4, and open the hull valves on ALL the other tanks???

All blowing valves of the emergency blowing manifold were located external - so available for diver. The flood valves of the ballast tank 3 was almost never closed when U-Boat was at sea. If the buoyancy gained by blowing all three main ballast tanks was not sufficient to rise the boat, the other measures had to be taken.

To know, how emergency blowing manifold could like, you can sea this diagram:

http://dreadnoughtproject.org/plans/KM_Uboot_Type_II_1934//bergungsplan_100dpi.jpg (http://dreadnoughtproject.org/plans/KM_Uboot_Type_II_1934//bergungsplan_100dpi.jpg)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 16 May , 2014, 01:17
Tore,

The chief engineer is mostly stand by if something should go wrong and engineers would be required. During battlestation in our navy however, the chief engineer worked with the CO with distance bearing/ calculation. Down below is a picture with the CO on his knees at the navigation periscope and I calculating the distances during a dummy attack just to give you an idea.
When using the attack periscope the chief engineer was not in the tower but in the CR. At the attackperiscope the CO could get a lot of info directly, however we did not trust the German fruitmachine so the CE had to do some calculation passing messages up to the tower verbally.

Could you say something closer about Norwegian experience with German fruit-machine and  Norwegian practice of torpedo fire control, please?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2014, 02:22
Don
I believe Maciek has answered the rest of your questions in agood way. I would only add to the compensating tanks post I forgot to mention the air/ venting  system which we have touched upon previously as seen on plate 7 and 17,( the system with the sightglasses and muffler at the aft part of the attackperiscope casing). I guess using the dicussion on the Q system would help to understand the sketches.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2014, 02:35
Maciek.
Torpedo firing and the fruitmachine was not really under my responsibility, that was the torpedopeoples job, so I am afraid I cannot help you very much. I did only the manual calculation using graphs and tables after receiving the COs info of speed, bearing etc. We had a student on board from the technical university in Trondheim taking his master on this "computer" it was of course the prehistoric computertime, but  I am sorry I cannot contribute in any sensible way.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 16 May , 2014, 16:02
The purpose of the compensating tanks is to compensate for the changing the weigths of the submarine. The weigth is changing all the time, extra people are coming on board, fuel, freshwater and provision are consumed etc. Thus you have to compensate this by taking water in and out of the compensating tanks fairly often.
 

Tore, does it mean that you had to weight all the provisions in advance, before embarking them? What about the crew? did you know the weight of every single men aboard or you just assumed a mean weight of, for instance 70 kg per crewmember? also, did you take in consideration the possible weight loss of the people aboard or it was ininfluential?
How often did you calculate the weight change of the submarine?
thanks
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 May , 2014, 17:32
Hello Mr tore,


I now know exactly where that Plate 17 came from....  The manual "U-Bootskunde für U-Boote Bauart VII C, Stand vom 15.7.40." - this manual has an appendix in the back of the book where you will find Plate 16 and Plate 17...


5.  Anblaseleitungen, Notausblaseund Raumnotluftleitung


Translate to English?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 May , 2014, 20:28
Hello Mr. Tore,


Plate 16 = I assume the 1 vent valve in the diesel room to vent the trapped residual air in both D2 tanks is located in the roof area.  Do you have a photo of this valve?  Are the venting lines going from the back end of the tanks to the valve located internal or external to the pressure hull?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 17 May , 2014, 00:32
Tore,
Torpedo firing and the fruitmachine was not really under my responsibility, that was the torpedopeoples job, so I am afraid I cannot help you very much. I did only the manual calculation using graphs and tables after receiving the COs info of speed, bearing etc. We had a student on board from the technical university in Trondheim taking his master on this "computer" it was of course the prehistoric computertime, but  I am sorry I cannot contribute in any sensible way.
Thank you Tore for your answer. It would be interesting to take master on such piece of equipment (as well as reading such scientific description).


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 17 May , 2014, 00:40
Don,


Plate 16 = I assume the 1 vent valve in the diesel room to vent the trapped residual air in both D2 tanks is located in the roof area.  Do you have a photo of this valve?  Are the venting lines going from the back end of the tanks to the valve located internal or external to the pressure hull?


As the vent valve of the Tauchbunker 2 is located outside the pressure hull, it is hard to get photo. But if you mean the drive for this valve - one is located in the control room - on the aft bulkhead - over the hatch to the petty officers room - large red wheel on the stb side (the wheel on the port side is the drive for the Tauchtank 1). In the diesel engine room, to the driving shaft going from control room, the other wheels are attached, so the vent can be operated also from the diesel engine room.
See also here: http://models.rokket.biz/index.php?topic=106.msg13275#msg13275


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2014, 01:18
SG.
A full control of the weigths in and out is necessary. This is particularly elaborate after major refitting, preparing for long patrols,provision,fuel, torpedoes taken on board and compensating for shooting same etc. In my days a rough estimation of each person would be 75 kgs today you would probably add another 10 kgs pr. person I guess ;D. Not only the weights taken on board, but the salinity and temperature of the sea had to be taken into consideration. In addition to weights taken on board you had to know where it was stowed as the tilting moment has to be taken into consideration for the trim as well. The influences of these shifting of weigths was many times based on experiences rather than calculations. As mentioned before f.i. prior to sounding the alarm for diving stations you knew that 400 liters had to be shifted from aft to forward trimtank. You could of course compensate a lot by the hydroplanes and the movement of a single person or normal watchchanging would not require a trim changing you compensated by the hydroplanes. The need for  fairly extensive corrections  is why there are  elaborate systems of compensating- and trimtanks as you want to have an optimal boat for easy handling of hydroplanes. Tanks were sounded every day and adjustment was carried out accordingly.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2014, 03:00
Don.
Residueventing MBT 2
I believe Maciek has answered in a good way. I can only add that the drive rod from the controlroom goes into the engineroom and ends up at frame 21 in a bevelgear where it goes through the through the pressure hull. I am posting a photo showing the arrangement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2014, 05:02
Don.
Further to my previous post I am sending a bad photo showing the enginroom hand wheel for the residue ventingvalve, the rod continues to the CR.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 17 May , 2014, 08:29
Very interesting, Tore. Thank you very much!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 May , 2014, 12:40
Thank you Mr. Tore,


That explains a lot and I'm very grateful for your patients and understanding.  It looks like you have answered many of my questions before and I do apologize for being such a bother.


Several years ago, I started building an OTW Radio Controlled model of a Type VII C U-Boat "U-96" which has a fiberglass hull and a brass deck and tower.  The kit came with 2 flat tower side sheets and the laser cut out deck sections.  I had to manufacture the rest of the tower components from brass plate and rods and assemble everything with a small soldering gas torch.  It took me about 2 years to complete the U-Boat structure, but I have not installed the water tight chamber along with the all the electronics (receiver, servos. dive system, speed controller, depth controller, and pitch controller, plus tons of other stuff).  To complete my U-96 project it would take well over $3,000 and lots of time.  When it is completed, U-96 will be capable running on the surface, or diving to a predetermined depth in a lake or pool.  Today, U-96 sets on a table in my library as a huge 84 inch long accurate display model.


Sometime next week, I will take some new photos of U-96 and post them on this web site.  Oddly enough, this is the Accurate Model Parts site... :)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 May , 2014, 23:15
Hello Simon,


I was looking at your drawing new2u and now I see where you have configured in the D2 tanks residual vent valves b1 in your WorkingDrawingV03.  Could the d1 control valve wheels be in the ceiling of the diesel room?  That sounds like a Mr. Tore question, if he has not already address the issue.


My offer still stands...  Simon if you ever decide to publish a book with all your Type VIIc drawings, then I would be one of the first in line to purchase a copy.  Your work is that good!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 01:12
Don.
Some time ago we discussed these valves see page 53 thru 55 in this thread. However I better sum up: The venting system of both the main venting MBT 2 and 4 as well as the residueventing MBT 2 have all fairly long external venting pipes which are controlled from the inside by common ventvalves for quick handling. The main venting of MBT 2 and 4  port and stb from CR and  the residueventing MBT 2 port and  stb from the CR and engineroom. This implies some external piping which might be susceptible to damages which could be fatal. To overcome this risk the system has valves close to each MBTs so you can shut off  each tank separately eliminating the external vent pipe. These valves should be operated from inside.  The valves are having spindles going through the pressurehull and ending up in a removable T bar on plate 6. The valves seems not to be fitted on the residue venting system and thus no valvespindles in the engineroom.  To make it even more complicated to you, the MBT 2 and 4 port and stb. have a 3rd valve in the ventduct outside the pressurehull, these are gatevalves and used for shutting off the tanks while used as fuel bunkertanks. The gatevalves are placed outside the pressurehull under the casing and are not operated from inside the pressurehull thus not valvewheels in the engineroom which is according to plan16.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 06:56
Don.
Emergency ventvalve MBT 4 port.
Further to my post this morning I show you a bad photo of what I believe could be the valvespindle of the port MBT4s emergency shut off valve for the ventline. I Guess it`s situated between frame 47 and 48 slightly aft of the navigation periscope. The starbord valve is hard to spot as on all the photos I have, a lot of stuff are in the way.The same goes for the valves of MBT2, you shall probably find the spindles in some of the upper small cabinets in the PO mess aft of the CR.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 18 May , 2014, 10:15
Hi Tore,
To make it even more complicated to you, the MBT 2 and 4 port and stb. have a 3rd valve in the ventduct outside the pressurehull, these are gatevalves and used for shutting off the tanks while used as fuel bunkertanks. The gatevalves are placed outside the pressurehull under the casing and are not operated from inside the pressurehull thus not valvewheels in the engineroom which is according to plan16.
Accidentally I have found something related with the gate valves. See this Deutsche Wochenschau: http://www.youtube.com/watch?v=aqdvK2ZtxoA , since 7:30. The reader says something like: Bei schwerer Wetter muß ein Tauchbunker aufgestellt werden. I think, that camera operator recorded operation of converting Tauchbunker from fuel tank to ballast tank mode, when the crew member opened gate valve on the venting duct.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 11:13
Maciek.
Unbelievable what you are noticing. Indeed I guess the man on deck seems to open the gatevalve on fuel/ ballast tank 4 port. which means it is converted into a ballasttank by using a T bar on the valve from the casingdeck under bad wheather.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 May , 2014, 15:10
Great spotting Maciek!

It looks like I will need to update my drawing, from a hex shape to a square shape (7:37) peg on top of the valve  :D

Simon
 

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 May , 2014, 17:58
Hi Simon,


It looks like the crewman is holding a "T" bar tool with a collar on the end of the shaft with a recessed square for fitting over the screw to unlock the access door (the tool)in the deck to the valve below.  the crewman also has a 2nd tool in his hand that looks like a double hook with a square cut-out to access the valve (The tool 2).  I'm not sure why it was designed like that?  Am I right on this?  (see photos)


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 May , 2014, 18:11
Don, yes on the 'square'. I will need to change my drawing from hex shape to a square shape ;D

The hatch covers for these valves are different between the older and the newer style of decks of Type VII’s.
 
For the newer style of deck, the hatch cover for tank 1 valve is long/narrow because of the large lower Wintergarten (left of drawing) and tank 4 is just a key hole in the deck.

(https://farm3.staticflickr.com/2909/14214148021_2b9a3956ea_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 May , 2014, 20:12
Hello Mr. Tore,


I must have been sleeping...  I totally missed the photo of the Q tank Kingston (now believed to be Mushroom) valve spindles in the photo.  I modified the photo so that I will not miss that again.


Is it normal for the valve wheel or handle not to be on the valve shaft?  I bet the Captain would really get up set if the crewman said they can't find the valve wheel during an crash dive and they can't express the Q tanks!!!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 May , 2014, 23:05
Hi Simon,


It looks like the crewman is holding a "T" bar tool with a collar on the end of the shaft with a recessed square for fitting over the screw to unlock the access door (the tool)in the deck to the valve below.  the crewman also has a 2nd tool in his hand that looks like a double hook with a square cut-out to access the valve (The tool 2).  I'm not sure why it was designed like that?  Am I right on this?  (see photos)


Regards,
Don

I also saw the 2nd tool and was wondering what its for ???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 23:25
Don.
The spindles which you have marked are the spindles for the MBTS 4 aft Kingstons. If you look at page 111 on this thread you`ll see Maciek correction and the special mushrom floodvalve fixed wheelhandle. This valve have a much smaller floodarea than the adjacent MBT4 Kingstons as discussed.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 23:36
Don.
Valves and Kingstons spindle.
On the VIICs a number of valves end in a spindle without handle or wheels. You have several reasons for that. Spacesaving and preventing accidental opening of special important valves. It is normally used on valves not so frequent in operated. The CO don`t have to worry about the Q,  the floodvalve wheelhandle is always there. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 May , 2014, 23:45
Simon and Don.
Nice to see you are back Simon. The strange tool you have noticed is a wheelclaw. The tool is used on wheelhandles on valves which are hard to open. You put one "claw" on the spoke and the other on the wheelrim thereby you get a rod giving you a better momentum for opening the valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 May , 2014, 23:47
Hello Tore,


Simon pointed me to this great thread, I'm developing a Type VII simulation game.
It's amazing to read what kind of details you remember after many decades! I hope you could answer me some questions (unfortunately actually I have a lot of questions).


- I'm currently working on the simulation of the G.W. engine for my game.
The load is simulated with a simple calculation (propeller law) so it's like a test bed.
http://www.wolves-of-the-atlantic.com/downloads/Enginetest/Enginetest.html (http://www.wolves-of-the-atlantic.com/downloads/Enginetest/Enginetest.html)
(It will load the Unity plugin to play the simulation which is harmless. Ignore the bad graphics, it's just to give me a primitive visualization)


My biggest problem with the simulation is the acceleration of the engine itself because it's impossible for me to simulate the resistance caused by each part of the engine. I went with the power delivered to the shaft as basis of my simulation instead.
Basically the drag of the working propeller and the diameter and weight of the propeller and shaft are limiting the acceleration and revolutions per minute. The engine power itself is based on the amount of fuel per revolution (can be controlled with the slider).
It seems that the simulation matches the real world thing. But what about the time it takes to accelerate engine RPM? I have absolutely no idea how fast such an engine can accelerate to different RPMs.


- And the fuel consumption shown in the simulation, does it make any sense to you?


- Another question is the AK speed (highest continuous) which should be 470 RPM, was it really possible to run the engine at 470 RPM for longer times? And 490 RPM for something like half an hour?


- From what I've read on the Type VII manual I think the governor limits RPM to not exceed 490 RPM + 10% (which would be 539 RPM). How fast does this governor work? I think it pushes a kind of lever to limit the fuel inflow, does it have a "way" from 490 to 539 RPM or does it instantly limit fuel inflow?


- The manual says the engine can't be started with the supercharger clutched in. And the supercharger can't be clutched in below 390 RPM.
Also the fuel lever can't be moved to a higher position than something that would result in about 420 RPM unless the supercharger is clutched in. Now my really stupid question: do you have to declutch the supercharger when going from higher speed to below 390 RPM???


- What is the minimum RPM the engine can run at?


- do you remember the RPM (or loss of speed) when charging batteries (at the different drive modes)?


- Is it correct that you can engage the clutch of the diesel while the engine is running up to 350 RPM? What when you switch from diesel to E-Machines? The E-Machine operate at a maximum of 280-295 RPM, do you need to reduce the diesel RPM to below 300 RPM before you clutch in the E-machine or isn't it necessary (manual says the generator can work as a brake when propellors break through the water surface in bad weather).


- how long does it take to stop and start engines to reverse?


enough questions  ;D


regards


Mark
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 00:11
Mark.
Welcome to the thread, yes it is indeed a lot of interesting questions which I need a bit time to answer. Please be aware of the many alternative ways you can operate the engines. Singel engine, dual engine, engines declutched completely from shafting, clutched in E generators, clutched in propellers, run with different batterycharging , combination of propulsion and  batterycharging, various type of schnorchling etc. I`ll try go into  into your questions one by one if you have patience with a man going on 86. I`ll probably have a few answers ready by today. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 00:20
That's great thank you! I have a lot of patience after all the endless search on the internet before  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 03:22
Mark
The GW engine fuelinjection is controlled directly by the fuel handle on the maneuver stand, thus it is an immediately respond of the engine, a matter of 3-4 seconds from 0 to 350 rpm with engine disengaged from the shaft system. The governor is only maintaining the revs set manually by the fuelhandle and is controlled by centrifugal weights on a shaft driven from the camshaft drive. As the force for moving the fuelrack is not sufficient, there is a linkage from the governor to a slide on a hydraulic servomotor which moves the fuelrack according to the variation of torque to maintain the preset RPM, a detailed analyze of the system is discussed previously on this thread. The servomotor is a delaying element, but only at the variation of torque to maintain a preset revs. I would say a second or two. The variation of torque can be due to inertiaforces like clutching in generator/ E motor, tailshaft incl. propeller or resistance due to generator load or Emotor drive, torsional vibrations and propeller torque due to speed, waves and in shallow waters, depth under the keel etc.
The fuelconsumption for this engine would be between 157 g/bhp and 165 g/bhp, I should assume.
The max continuous rpm is 470, I guess you could run that for hours,  we usually were operating at 460. The overload rpm 490 was limited to a half hours run as far as I remember.
Increasing the rpm to 539 seems to be excessive, we never exceeded 490. By adjusting the linkages you could increase the revs beyond the preset values.
I assume you would have more questions on my answers, so just fire. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 04:01
Mark.
Supercharger GW engines.
The GW engine is basically a normal aspirated engine which had a booster(Roots blower) driven via a doublecone clutch from the camshaftdrive. At low load and rpm up to 350 rpm you clutched in the blower by moving a handle on the boardside of the engine at the maneuverstand, by doing that you shut off the normal aspirated air inlets and opened for the booster airduct from the blower thereby you increased the airsupply, the bmep and output of the engine by being able to inject more fuel.The interlocks on the fuelrack and the declutching of the blower was indeed executed as you mentioned.
You could run the engine  some 100-150 rpm I guess.
There are different battery chargingloads, starting by not cruising, only charging at very high loads when your batteries were low and very light, just topping up the batteries. As far as I remember the rpm varied with the load I can`t remember the revs. When cruising you put the chargingload according to the requirement of the speed and the timeneed for getting batteries fully charged ,up to the decision of the CO.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 06:41
Mark
Diesel engine clutch.
As the blowerclutch, the engineclutch was a double cone frictionclutch, the difference being the size and it was pneumatic/hydraulic operated. I guess you could engaged the clutch at 350 revs, but the wear and tear increases with the speed and inertia forces so we usually started with the clutch engaged. Engaging the clutch at relatively high speed created a lot of smoke allthough nobody knew about the asbestos danger, the smoke could be unpleasant in a confined space.
The starting procedure after surfacing was a bit cumbersome, you wanted to get the engine ready as soon as possible in order to exhaustblow the ballasttanks as you was semisurfaced and the  boat was in an unstable position. However you had always some seawater leakages in the exhaust system and some time these leakages could even fill the cylinders. In order to prevent waterstroke, you opened up all the indicator cocks and blow air through the cylinders to get all the water out. Then came the normal starting after shutting the indicatorcocks ,run the engine to some 100 rpm. by air before admitting fuel to the cylinders and ignition. It could take at least 3 minutes.
You question on maneuvering.
After 1942 I guess the GW VII Cs diesels were not direct reversible, the reversing mechanism was removed and the VII Cs were maneuvered by the E-motors only. Direct reversing of a diesel is slow, complicated (expensive), consumes air and is not necessary on a submarine. Most WW2 submarines were maneuvered by E motors. If this is not clear just put forward you questions.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 May , 2014, 09:39
Hello Mr. Tore,


If the crewman was using the wheel-claw tool to operate the gate-valve below deck, then in this instance the wheel-handles were present on the gate-valves.  Perhaps Simon's first drawing was correct after all...


Thanks for the answer about the Q tank missing hand-wheels...


Q tank question - the tank had its internal support structure modified with knee braces to provide support for external pressure.  However, this will not provide for increased internal pressure in the tanks.  This would be a good reason for monitoring the internal pressure of both Q tanks. 


I can think of only two reasons for Q tank to experience increased internal pressure of the magnitude required to burst the tank.


The mushroom valve at the bottom of Q tank were left open after an express.  Now, as the U-boat dives to a greater depth, the water pressure compresses the air in the tank and could causes the tank to burst.   I can see the same situation happening if the mushroom valve were leaking.  I don't believe the venting air pressure could ever cause this problem.


Diving question - as the U-boat goes to a greater depth the actual volume of the pressure hull decreases because of external pressure, and this changes the neutral buoyancy to a negative buoyancy.  Is anything done to adjust for the loss in buoyancy internally like pumping out water from Regulating tank 2?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 May , 2014, 09:49
Don,

The mushroom valve at the bottom of Q tank were left open after an express.  Now, as the U-boat dives to a greater depth, the water pressure compresses the air in the tank and could causes the tank to burst.   I can see the same situation happening if the mushroom valve were leaking. 

This is not a case - when the flood valve of the negative buoyancy tank is left open or is not tight, the pressure inside the tank is always the same as outside - so there are no forces affecting the tank.

Diving question - as the U-boat goes to a greater depth the actual volume of the pressure hull decreases because of external pressure, and this changes the neutral buoyancy to a negative buoyancy.  Is anything done to adjust for the loss in buoyancy internally like pumping out water from Regulating tank 2?

Quote
     
181.  To proceed to great depths (more than 40 meters), the Engineering Officer gives the depth order and the depth changes in increments of 10 meters to all rooms verbally man to man.
         Because the boat loses volume at greater depth, it must be made lighter by timely pumping (for type VII boats approximately 1 ton per 100 meters).  It is appropriate to pump out a greater amount, because the boat will be heavier by the accumulating leak water anyway.
http://uboatarchive.net/DivingRegulations.htm

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 10:30
Don.
Maciek has answered your questions excellent. I can only add, apart from the depth, the variation in salinity and temperature influence the buoyancy of the boat as well. This can be significant fi. when you are submerged  in a fjord like the very deep Norwegian fjords particularly when the glaciers are melting and freshwater are in layers between the seawater can give you a bumpy ride. However you can compensate a lot by the hydroplanes, but in order to keep the margins you want to correct your buoyancy as much as possible.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 May , 2014, 11:23
Maciek has answered your questions excellent. I can only add, apart from the depth, the variation in salinity and temperature influence the buoyancy of the boat as well. This can be significant fi. when you are submerged  in a fjord like the very deep Norwegian fjords particularly when the glaciers are melting and freshwater are in layers between the seawater can give you a bumpy ride. However you can compensate a lot by the hydroplanes, but in order to keep the margins you want to correct your buoyancy as much as possible.

I would add to Tore statement, that although air compressed in the tanks is harmless to the boat construction, but it is highly undesirable due to volume changes along with depth, which results in the changes of buoyancy.
That's why the residual vent of the ballast tank 2 is so important, and that's why, the Germans had special maneuver after submergning the boat - so called durchpendeln. That means slightly trim the boat bow and aft, to remove residual air from ballast tank 1 and 5.

Quote
81.  If the flooding maneuver runs normally, the order follows:
         Commander:  "Bring boat to x tons positive buoyancy and put in balance".
         Engineering officer repeats the order.
     
         The boat is brought to a positive buoyancy of approximately 2 tons by flooding the regulating tanks on the orders of the Engineering Officer initially without consideration of the trim.  Now the boat becomes sensitive in longitudinal stability and is oscillated by means of small trim adjustments to purge the residual air from the ballast tanks.
     
         The boat is brought to the ordered buoyancy by further flooding the regulating tanks.  From 2 tons of positive buoyancy the Engineering Officer continually reports decreases in the remaining buoyancy.
http://uboatarchive.net/DivingRegulations.htm

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 11:43
The starting procedure after surfacing was a bit cumbersome, you wanted to get the engine ready as soon as possible in order to exhaustblow the ballasttanks as you was semisurfaced and the  boat was in an unstable position. However you had always some seawater leakages in the exhaust system and some time these leakages could even fill the cylinders. In order to prevent waterstroke, you opened up all the indicator cocks and blow air through the cylinders to get all the water out. Then came the normal starting after shutting the indicatorcocks ,run the engine to some 100 rpm. by air before admitting fuel to the cylinders and ignition. It could take at least 3 minutes.
You question on maneuvering.
After 1942 I guess the GW VII Cs diesels were not direct reversible, the reversing mechanism was removed and the VII Cs were maneuvered by the E-motors only. Direct reversing of a diesel is slow, complicated (expensive), consumes air and is not necessary on a submarine. Most WW2 submarines were maneuvered by E motors. If this is not clear just put forward you questions.
Tore


Thank you! Those two facts are completely new to me.


After surfacing in a dangerous war situation would they have taken the risk to start the engines without blowing possible water out of the engines first?
(OK, I just have to think what kind of situation this could be… possibly makes no sense at all, the only reason to surface while being in range of enemy vessels would be to show the white flag)
I guess the U-Boat can run on E-Machines during this procedure? (or isn't that a good idea without blowing ballast tanks first?)


Then I'll will allow usage of reversed diesel in the game only if the E-Machines are damaged.


Quote
I guess you could engaged the clutch at 350 revs, but the wear and tear increases with the speed and inertia forces so we usually started with the clutch engaged.


This makes sense with the information of the seawater leakage in the exhaust system after surfacing. And I think that also means usually E-Machines were shut off until the ballast tanks were blown? Otherwise the shaft would still run at something close to 290 RPM when the diesel is clutched in which is basically the same stress on the clutch just flipped.
So you switched from diesel to electric but usually avoided to switch from electric to diesel while running?






 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 12:28
Mark.
We had our ways and means if a quick start was important, in peacetime f.i.heavy weather. It would take an experienced engineer. Before blowing the tanks (by air)and the mainclutch was still disengaged, running on E motors, you opened the indicator cocks to drain as much water as possible, then carefully admitted air ( low pressure) to the cylinders turning the engine very,very slow to blow out the water all prior to surfacing, then you started the engine as soon as the diesel air inletvalve opened. The procedure would  create some overpressure in the boat and required a very experienced crew for correct timing.  You normally used the E-motors all the time to keep the boat into correct position while exhaustblowing the tanks. When the tanks were fully blown you reduced the E-motor revs and engaged the main clutch and run on diesel.  I think nobody would take the risk of starting the engine without a watercheck as a waterstroke would damage the engine beyond searepair.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 12:44
Mark.
If you allow the usage of a reversible diesel in your games the relevant boat has to be one of the pre 1943 types, you clearly see the difference of the engine as the direct reversible engine has a dominating vertical reversingcylinder at the maneuvering place forward of the engine see photo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 14:44
Thanks Tore, it's an early VIIC in the first version of the game.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 May , 2014, 16:07
To complete Tore's detailed explanations - the German war-time description of G.W. Diesel engines gives following data:
fuel consumption during stationary trials:
overload (1/2 hour), 1612 HP, 494 RPM, 195,5 g/bhp
overload (2 hour), 1515 HP, 486 RPM, 190,2 g/bhp
full load, 1400 HP, 470 RPM, 190 g/bhp
3/4 load 1056 HP, 429 RPM, 187,4 g/bhp
1/2 load without blower, 702 HP, 375 RPM, 182,3 g/bhp
1/4 load without blower, 350 HP, 298 RPM, 197,5 g/bhp

standard revolutions: 470 RPM
highest revolutions: 515 RPM
lowest revolutions (with blower): 130 RPM
lowest revolutions (without blower): 100 RPM

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 16:36
Thanks,  ;D  I've just realized you are the one who translated the Type VII manual on Jerry's website to english and Don Prince seems to be the one who had the german original copy.


Any chance that I could I get a copy of the german original? It would be easier to read for me.


I'm currently a bit confused about the engine telegraph and correspondending RPM. Tore said they usual were operating on 460 RPM.
The manual says:



KF = 180.0
LF = 275.0
HF = 340.0
2xHF = 396.0
GF = 435.0
AK = 471.0
3xAK = 480.0


The british report on U570 wrote:



KF = 161.0
LF = 263.0
HF = 310.0
2xHF = 404.0
GF = 469.0
AK = 485.0


Any idea what's the reason for the difference?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 17:46

full load, 1400 HP, 470 RPM, 190 g/bhp



hehe, my confusion rises…

The 1400 HP at full load should be shaft horsepower (manual says 1400 SHP, 470 RPM at full load) but the fuel consumption is gramm per brake horsepower.
The manual says fuel consumption of the G.W. is 254 kg/h at full load (470 RPM, 1400 SHP) which is 0.181 gramm per SHP
I think consumption per bhp should be lower than per shp which makes the difference even worse. But actually I have no idea. :D


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 May , 2014, 18:21
Hi Maciek,


Newton and Bernoulle and a bunch of other dead people would be ashamed of me because I ignored what my High School physics teacher (Marist Brother Matthew) taught me 55 years ago...  I was just in such a hurry to get that darn Q tank to burst and ignored the basic fluid mechanics that I had known for years...


Again, thanks for the physics re-fresher course...


Don_


PS - If anybody is doing he the math, I will be 73 on June 3rd
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 May , 2014, 23:00
Mark.
Reverting to my notes on waterleakages in the exhaust system I would emphasize filling the cylinders was really exceptional and has happen to me once, nevertheless the blow thru with open indicators was a routine after being submerged.
 Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 May , 2014, 23:09
Mark.
Reverting to my notes on waterleakages in the exhaust system I would emphasize filling the cylinders was really exceptional and has happen to me once, nevertheless the blow thru with open indicators was a routine after being submerged.
 Tore


OK  :)


I've just found a website which says bhp and shp is identical? :o Is that true?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 00:02
Maciek, Mark.
Fuelconsumption, output.
The BHP is referring to the output measured at the enginemanufacturers testbed under controlled environment. BHP stand for Brake Horse Power and is referring to the testbed calibrated waterbrake which brakes the engine at various rpm in order to put up an output graph for the buyers approval according to the contract output. The other output designations like shp, is less accurate and I assume could be measured by a torque meter on the shaft at various places the output will then vary fi. if you have a liquid coupling after the engine and take readings after the thrustbearing, gearboxes etc. thus less specific designation.
Fuelconsumption is likewise measured on the testbed in close connection with the waterbrake for accurate output readings, temperature, barometric pressure etc. Then the most important detail, the reference fuel. Dieselfuel is not an accurate specification as you have many variations and I guess during WW2 it was a difference between the German diesel fuel and to days prime diesel quality called gasoil. For consumption measurement the lower calorific value is the most important, it can vary considerably like 42.000 MJ/kg to over 44.000 MJ/kg. So if you want to compare apples don't`introduce pears. So I assume without knowing the lower calorific value of the reference fuel you cannot compare the various fuel consumption figures. ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 01:43
Mark.
Deviation on the engine telegraphs rpm.
We never used the engine telegraph designation and corresponding rpm which are put up in the lists you are referring to. I believe it is strange to have stages as 396 and 471 rpm. It looks to me as composed by somebody behind a writingdesk. Whatever order was given, you adjusted the engines to an approximate rpm level and the governor kept the engine at that level plus minus 3-5 rpm. We did not use these accurate figures as this was not a science issue. The CO passed on messages verbally if some unusual outputs would be necessary.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 May , 2014, 02:05
Hi Mark,

full load, 1400 HP, 470 RPM, 190 g/bhp


hehe, my confusion rises…

The 1400 HP at full load should be shaft horsepower (manual says 1400 SHP, 470 RPM at full load) but the fuel consumption is gramm per brake horsepower.
The manual says fuel consumption of the G.W. is 254 kg/h at full load (470 RPM, 1400 SHP) which is 0.181 gramm per SHP
I think consumption per bhp should be lower than per shp which makes the difference even worse. But actually I have no idea. :D

it seems, that in the manual (that is U-Bootskunde fur U-Boote Bauart VIIC available on the uboatarchive.net) are given rounded values of the power
(1600 against 11612, 1515 against 1500 and 1400). I think, that rounded values are given for practical reasons, as the accurate value were measured
using waterbrake under test conditions (as Tore explained).

I have one note - in the original German documents, the power is nominated in the PSe units, that is equivalent of bhp. I was mistaken, translating it to the SHP as on the uboatarchive.net.

In hurry, I have given fuel consumption in the g/bhp, while in the original documents is given as g/PSe/h. I have attached the scan of the data table.
As a bonus - chart of the power and fuel consumption in the relation with the RPM.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 May , 2014, 02:52
There are different battery chargingloads, starting by not cruising, only charging at very high loads when your batteries were low and very light, just topping up the batteries. As far as I remember the rpm varied with the load I can`t remember the revs. When cruising you put the chargingload according to the requirement of the speed and the timeneed for getting batteries fully charged ,up to the decision of the CO.

The RPM loss while charging you can roughly estimate using these documents. They are valid for cruising submerged (while snorkeling), but I do not have nothing better.

http://www.ubootwaffe.pl/images/okrety/instrukcje/chrapy/preliminary_snorkel_description1.jpg
http://www.ubootwaffe.pl/images/okrety/instrukcje/chrapy/preliminary_snorkel_description2.jpg

The starting procedure after surfacing was a bit cumbersome, you wanted to get the engine ready as soon as possible in order to exhaustblow the ballasttanks as you was semisurfaced and the  boat was in an unstable position. However you had always some seawater leakages in the exhaust system and some time these leakages could even fill the cylinders. In order to prevent waterstroke, you opened up all the indicator cocks and blow air through the cylinders to get all the water out. Then came the normal starting after shutting the indicatorcocks ,run the engine to some 100 rpm. by air before admitting fuel to the cylinders and ignition. It could take at least 3 minutes.

After surfacing in a dangerous war situation would they have taken the risk to start the engines without blowing possible water out of the engines first?
(OK, I just have to think what kind of situation this could be… possibly makes no sense at all, the only reason to surface while being in range of enemy vessels would be to show the white flag)
I guess the U-Boat can run on E-Machines during this procedure? (or isn't that a good idea without blowing ballast tanks first?)


Then I'll will allow usage of reversed diesel in the game only if the E-Machines are damaged.

Quote
I guess you could engaged the clutch at 350 revs, but the wear and tear increases with the speed and inertia forces so we usually started with the clutch engaged.


This makes sense with the information of the seawater leakage in the exhaust system after surfacing. And I think that also means usually E-Machines were shut off until the ballast tanks were blown? Otherwise the shaft would still run at something close to 290 RPM when the diesel is clutched in which is basically the same stress on the clutch just flipped.
So you switched from diesel to electric but usually avoided to switch from electric to diesel while running?

For the surfacing procedure (including exhaust diesel blowing) you can read here:
http://uboatarchive.net/DivingRegulations.htm
The corresponding paragraphs - 201 - 221 and 306 - 312.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 08:51
Mark.
Deviation on the engine telegraphs rpm.
We never used the engine telegraph designation and corresponding rpm which are put up in the lists you are referring to. I believe it is strange to have stages as 396 and 471 rpm. It looks to me as composed by somebody behind a writingdesk. Whatever order was given, you adjusted the engines to an approximate rpm level and the governor kept the engine at that level plus minus 3-5 rpm. We did not use these accurate figures as this was not a science issue. The CO passed on messages verbally if some unusual outputs would be necessary.
Tore


That's extremely important info!  :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 09:17
I have one note - in the original German documents, the power is nominated in the PSe units, that is equivalent of bhp. I was mistaken, translating it to the SHP as on the uboatarchive.net.

In hurry, I have given fuel consumption in the g/bhp, while in the original documents is given as g/PSe/h. I have attached the scan of the data table.
As a bonus - chart of the power and fuel consumption in the relation with the RPM.



That's exactly the kind of data that I need :-) I've made a crude interpolation from some data of the 9 cylinder machine of the IX before (which has same bore & stroke)


PSe (effektive Pferdestärke) is the power measured at the shaft of an engine (before the gears of a car) - wikipedia says PSe is like WPS (Wellen-PS) which is equal to SHP. After seeing this website I believe SHP and bhp are really the same http://www.engineeringtoolbox.com/horsepower-d_472.html (http://www.engineeringtoolbox.com/horsepower-d_472.html)
So I think you've made no mistake in your translation (but I gave up to study machine engineering after 3 days so I could be wrong and anything from the wiki is… well, we all know what I mean) also the whole PS thing is completely outdated so it's hard to google for it.


Your document with the graph seems to show PSe with auxiliary engines clutched in (angekuppelte Hilfsmaschinen) - the other document that is just a table is different and shows PSe without auxiliary engines.
You can also see that from the results - best to see at 375 RPM which is at 701 PSe on the table and at something like 715 PSe on the graph (both with supercharger).
It's great to have both because this could possibly make it easier for me to calculate the engine.
Where do you got those documents from?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 09:32
Tore, do you remember the impact of good and bad speeds (like hump and hollow in regard to the Froude number)? The slender shape of the hull combined with saddle tanks is pretty unusual. Do you remember if the resistance was clearly higher at bad Froude numbers so that you avoided those speeds?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 20 May , 2014, 09:41
So if you want to compare apples don't`introduce pears.

 ;D ;D ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 May , 2014, 10:16

Ruptured Negative Buoyancy Tanks (Q tank)
Let me try and make a fool of myself again...




http://www.uboatarchive.net/DivingRegulations.htm


33.  The pressure difference meters are to be monitored, particularly during expressing (danger of rupture with closed flood valve) and when the boat rises.  More than 2 atmospheres higher than outboard pressure is prohibited and must be equalized.[size=78%] [/size]
Equalization takes place after previous request to the Engineering Officer (for passing on to the conning tower) by complete opening of the "Vent negative buoyancy tank" valve, appropriately up to an internal pressure of 1.5 atmospheres (external pressure at periscope depth).


I can see two ways to rupture the Q tanks and the key element is the flood valve:
1.  Fail to close the Flood Valve until at depth
2.  Expressing at depth and then close the flood valve


Instance #1 - After expressing at 10 meters and failing to close the flood valve (bottom mushroom valve) will result in the Q tank's air being compressed.  This is not a problem for the tank at this point because the internal and external pressure are the same.  However, If the crewman closes the flood valve at 100 meters, now we have a problem!  As the boat rise with the closed flood valve, the outside pressure will decrease and the high internal pressure will stress the tank structure which was braced for external pressure.


Instance #2 - expressing the Q Tanks at a depth of 100 meters instead of 10 meters.  Again this is not a problem (same reason as above).  However, if the crewman closes the flood valve after expressing at depth, now we have same scenario with the compressed air in the Q tanks.  As the boat rises with the flood valve closed and decreasing external pressure, it is likely that the Q tanks will be ruptured because of the high internal pressure.


I sure hope I got it right this time...  If not, then I'll need another post high school lesson from Professor Maciek.


The manual says to monitor the pressure difference meter.  I assume that is the meter very close to the Q tank top vent valve (black and red wheel-handle).  Does this meter have a input line going to the inside top area of the Q tank, and a second input could be just a hole in the back of the meter to sample the internal hull pressure.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 11:35
 Mark.
I cannot remember we had any problem which could be related to the Froude number. We had a small problem more related to revs of the shafting than the speed of the vessel. When running on E-motors we had no problem. Diesel running could create a minor problem as you had a complex shaftingsystem having masses at different length from the engine, like in/out of propellers and in and out of E-motors, thus you got different torsional vibration patterns creating stresses in the shafting, further I assume we got certain free moments which could excite hullvibrations. I wouldn`t say they created problems. The latter could anyhow be avoided by passsing the revs area quickly. The torsional vibrations in the shafting were diffcult to discover as no torsional meter was installed, however the engines were equipped with torsional vibrationdampers up front, but I doubt if that took care of all situations. I have seen a few photos of VIIC shafts breakages which clearly was due to torsional vibration stresses, but if these engines had been equipped with a torsional vibrationdamper I cannot tell. I personally believe the most serious rpm related problem would be pitting of the propeller. The late war VIICs were equipped with  special cast steelpropellers. At the root of the propellerblades we had serious pittings due to cavitation. Cavitation is a noise problem as well , however we never figured out which revs should be avoided. Sorry this may be a bit off the topics. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 12:33
Don.
I am not sure if your man violating every rule for operating theQ and common knowledge for a submariner would have a long career in the submarine service, using the Q as a compressor ;D. However somehow the designers have taken such people into consideration. As we discussed previously each Q is fitted with a reliefvalve as well as differential manometers both are not shown on the pipediagram nor mention in the manuals I believe. The diff man is most probably connected to a common seapipe having direct connection to the sea on port side, serving the diff.manometers for the regulating tanks (4) and the Qs (2). The other pipes to the diff man. goes to each different tank, the pressure inside the submarine is irrelevant in this case it is  the  difference in pressure inside the Q and the sea which should be shown on the diffmanometer. When the inside pressure of the Q tanks exceed a safe level, the reliefvalve opens and the Q tank pressure is released, see photo below. This has happened not on my boat, but on another in my time. I guess your man would probably be offered a job as potatopeeler on the shore  submarinestation. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 14:39
BTW:

Tore, I know it's not perfect (and by far not as detailed as Simon's awesome drawings),
also it's still untextured and some stuff still missing…
and remember it's just for a mobile game.

What do you think of my command room model?  :)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom1.png)


(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom2.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom3.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom4.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom5.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 14:41



(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom6.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom7.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom8.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom9.png)

(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/commandroom10.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 15:09
Mark.
 I am impressed, very clean and easy to see the essentials. As you say some details are missing, but I guess you have everything necessary for the game-. I guess it is one of the earlier VIICs as you have not put in the schnorchel handle, however the radarmast is in place. I am not sure when same was fitted, Simon or Maciek would know.
Well done mark.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 15:26
Yes early VIIC but some things aren't like early VIIC, Simon showed me some things that won't belong there for early boats when I already had finished them. So actually I gave up on trying to make a command room for an early boat and will start the game with some generic interior. I have no idea what most of the things are anyway, I guess the radar mast is this one? If so then it does not belong to the boat the player will be able to use  :o  …but well if someone asks then I can call this an early experimental totally secret upgrade for the boat which is currently not working  :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 May , 2014, 16:02
Hi Mark,
well done -  very nice of model of control room.


Yes early VIIC but some things aren't like early VIIC, Simon showed me some things that won't belong there for early boats when I already had finished them. So actually I gave up on trying to make a command room for an early boat and will start the game with some generic interior. I have no idea what most of the things are anyway, I guess the radar mast is this one? If so then it does not belong to the boat the player will be able to use  :o  …but well if someone asks then I can call this an early experimental totally secret upgrade for the boat which is currently not working  :D


Radar FuMO 30 entered the service in 1943. More informations you will find here:
http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats
Besides the mast, you will have to remove the electronic equipment box located between the navigator table and forward bulkhead of control room.


One interesting (but little known) detail would be the refrigerator unit, which consisted of two parts -  food chamber located in the forward part of the petty's officers room, in the stb corner (just behind the control room bulkhead) and the compressor unit , which was located in the control room - over the trim and drain manifold.
On U-995, in this place is some kind of metal basket, and in the petty's officers room is quite modern fridge.
Tore, do you remember, if the KMN Kaura was ever equipped with German refrigerator unit?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 May , 2014, 16:41

Radar FuMO 30 entered the service in 1943. More informations you will find here:
http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats
Besides the mast, you will have to remove the electronic equipment box located between the navigator table and forward bulkhead of control room.


It just takes way to much time to create the whole boat interior (for my first version), so I will go with the incorrect upgraded command room and with command room only in this version. I just had no good reference pictures of what was installed at the place of the FuMO30 before.  It's hard to find pictures of the older interiors.
And I guess the FuMO30 requires a newer conning tower… First version will be a reduced sim anyway - the later full version will support different U-Boat upgrades.


I'm already working on the game since 5 years and need to release or the people who are already waiting to play it will kill me one day   ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 May , 2014, 18:53
This web site seems to have a good deal of information on the different HP ratings for ships...


http://www.scribd.com/doc/7174460/Basics-of-Ship-Resistance


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 May , 2014, 21:38
Hello Mr. Tore,


Thank you for the information on the pressure difference meter; it makes sense to compare the external sea water pressure against the Q tank internal pressure.


Besides my crewman who should be pealing potatoes on shore...  Are there  other ways to cause over pressure in the Q tank.  In any instance, it looks like the flood valve has to be closed.  Note*  I have been reading some articles and there looked to be quite a few problems with the Q tank flood valves leaking... 


I understand that there needs to be an automatic vent valve which will release gasses over a set pressure point.  At first it was hard to believe that the small relief valve and what looked to be a 3/8 inch line was large enough to handle the volume and pressure.  Especially when comparing it to the size if the pipe coming from Q tank to vent air into the hull through muffler.  That one looks to be about two inches in diameter.


Then. I guess reality sets in...  Q tank is 2 M3 on each side oh the U-boat.  Each side is equal to 70.6 FT3, or a little over 3 times the size of my 26 FT3 home refrigerator;  Q tank is NOT that darn big to begin with!  Both thanks combined only provide 4 metric tons of negative buoyancy.


The Type VIIC U-boat displaces 769 tons on the surface and 871 tons submerged...  It's amazing how much difference that 4 tons makes...


I apologize for all the trouble; I'm like a dog with a new chew toy and won't let go until I understand it!


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2014, 22:51
 Maciek.
Yes  I believe we had the german fridge. The door was right opposite to the officers and CPOs heads. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 May , 2014, 00:08
Don.
The reliefvalve is not an automatic inboard vent and is not dimensioned as such, it is a reliefvalve which releases the max pressure and give a warning that something is wrong, more like a manometer pointing to the red part of the scale, telling you have to act immediately.
Volume of Q. I believe you should look into the way Q is meant to work, it is rather a help to get thru the surface in the first stage. When  you boat is on surface in areas where a crashdive could be necessary the tank is full,  ventvalve shut and floodvalve open. At the crashdive command you are app 4 tonnes heavier than normal, believe me for a submarine  it is substantial. Strange enough it is a certain inertia to get down thru the surface before the hydroplanes takes over, that`s where the Q helps. As soon as you have been thru that part, the hydroplanes and propeller takes completely over and are substantial more powerfull than Q. Then Q is not needed anymore and you should blow Q. This is usually at app. 10 meters for a VIIC I believe. Blowing at greater depth is waste of air and should be avoided apart from emergencies. Submerged the submarine is controlled by hydroplanes rudders and propellers and the submarine has the normal neutral buoyancy with Q empty. We never experience a leaking Q floodvalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 May , 2014, 04:08
Mark,


Radar FuMO 30 entered the service in 1943. More informations you will find here:
http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats (http://www.ubootwaffe.pl/en/u-boats/equipment/radar-of-german-u-boats)
Besides the mast, you will have to remove the electronic equipment box located between the navigator table and forward bulkhead of control room.


It just takes way to much time to create the whole boat interior (for my first version), so I will go with the incorrect upgraded command room and with command room only in this version. I just had no good reference pictures of what was installed at the place of the FuMO30 before.  It's hard to find pictures of the older interiors.
And I guess the FuMO30 requires a newer conning tower… First version will be a reduced sim anyway - the later full version will support different U-Boat upgrades.


I'm already working on the game since 5 years and need to release or the people who are already waiting to play it will kill me one day   ;)

Well, great work anyway. I'm also waiting for the release :)
Have you created all compartments? Could you paste some screen-shots?
What kind of software are you using?

--
Regads
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 May , 2014, 05:07
Have you created all compartments? Could you paste some screen-shots?



No, only the command room. I want to build the whole interior for the later full version of the game which will also include at least Type IX. It just takes way too much time to build it. The main problem is there are no drawings that are of any use to build each tiny thing and when you build some parts too large or too small the whole then the whole thing won't fit at another position. It would be much easier to take a laptop and to build it while being inside U995 ;-)


This web site seems to have a good deal of information on the different HP ratings for ships...
http://www.scribd.com/doc/7174460/Basics-of-Ship-Resistance (http://www.scribd.com/doc/7174460/Basics-of-Ship-Resistance)


Can't count the number of website about this stuff that I've visited during the last 3 weeks :( …but actually haven't seen this one before which is pretty amazing for me because I thought I've seen all the PDFs now  :D   This is the first one that explains BHP and SHP in a good way






Tore, I guess you usually haven't accelerated the boat fast because of the fixed propeller pitch but what do you estimate would be a realistically looking time of acceleration to different (standard) speeds of the boat in seconds?


You said you could accelerate the declutched engine from 0 to 350 RPM in 3-4 seconds. Currently my simulated engine can go to 350 RPM in 7-8 seconds with propeller (ignoring the boats speed, like being fixed somehow)

Another thing I haven't understood yet :(  is the use of the supercharger. I still don't get if it was used below 390 RPM at all (once it was clutched in above 390 RPM)


Related to this: the document Maciek posted shows two RPM/Horsepower lines which would only make sense if the charger can be used below 390 RPM but even then it makes no sense because the manual says above 410 (or 420?) the engine can't be used without the supercharger. Can someone explain the two lines? My guess is it's just a theoretical interpolation for each line.
The fuel consumption shown makes sense to me as it does not show fuel consumption for RPMs of the uncharged engine above 420 and RPMs for the charged engine below 420.


I sometimes need more time to understand this stuff, my only real life experience with engines is a lawn mover and even this is 20 years ago. (I have no car, no driving license etc.)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 May , 2014, 07:54
Mark.
I have not any figures on the acceleration subject so it has to be guesswork, may be Maciek has some. Anyhow as you rightly stated the VIICs have  fixed propellers, as such it has bad efficiency in some ranges. If the vessel is at 0 speed and should increase to say 17 knots, you start the engines and stir up a lot of water for the first 100 m. Then the propellers gradually improves and you increase the revs to max. and you might achieve 17 knots at some 300 m. So  a guesstimate of 400m to obtain full speed of 17 knots. Which means an acceleration from 0 to 17 knots or app 31,2 km/hours over 400m. This is a pure guesswork from my side and take it for that.
Your simulation of an engineacceleration 0-350 rpm on 7-8 seconds seems not to bad to me with all the components connected.
Roots blower.
I believe the Roots blower is not an ordinary supercharger but rather a booster which is needed for getting extra max. output. The difference being as an ordinary turbo supercharger takes the thermal waste energy from the exhaustgases and thus improve both the output and fuelconsumption, the Roots blower require energy which is taken directly from the engine via the camshaft drive. Thus it takes a higher specific fuelconsumption to boost the engines, but it was at that time a common way to get more output of the engines. MAN submarine engines had a first generation turbocharger called the Buchi system and utilized the thermal energy of the exhaustgases.
 Thus you did not want to run the Roots blower unnecessary as it took energy from the engines. The GW engines operated as normal aspirated engines up to 390- 400 rpm I Guess, then you had to make use of the Roots blowers to get more output. At lower revs like below 390 the blower did not contribute anything in fact it took only energy from the engines for doing nothing, moreover it is not an advantage to have two big rotating weights connected to the camshaft drive wear and tear, torsional vibration. etc. So it was definitely disconnected at lower revs like 390 rpm.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 May , 2014, 08:53
Within 400 meters? Wow that seems fast. I'm upgrading the "engine" to the new data from Maciek's documents and I'm thrilled to see if my simulation automatically matches that later.


Quote
Your simulation of an engineacceleration 0-350 rpm on 7-8 seconds seems not to bad to me with all the components connected.


It's the result of an idealized calculation, I feared it would be too fast. "seems not to bad to me" is great because all I want to achieve is something that looks convincing at the end :)


Doh! I forgot that U 995 has the MAN engine.


BTW what about the basic colors? Are they correct in U995 today?
My current color setup looks like this:


(http://www.wolves-of-the-atlantic.com/downloads/Type_VII_Command_Room/colors.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 May , 2014, 09:29
Mark.
Remember it is guesswork, having said that, the VIICs were reasonably fast on the surface compared to other conventional submarines as they had fairly high dieselengine output,for the tonnage. wolfpack tactic. Submerged, the speed wasn`t that great.
U 995 engine. I am afraid you have misunderstood me,  the U 995 has Krupp Germaniawerft engines and as such Roots blower. I Guess the white colours are OK however on the Laboe U 995 people have gone mad with red paint and practically every cock and switch has been painted red, it looks as if she got the measles. Don't forget they have put up fluorescentic lights for the visitors, the lightings were not that bright.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 May , 2014, 00:33
I have been thinking on yesterdays acceleration estimates  and believe an increase in speed from 0 to 17 knots over 400 meters could be a bit too much, you should probably give it another 100- 150 meter thus the speedincrease over 500 to 550 meters. Still it is a guesstimate. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 May , 2014, 07:46
Thanks again, still some steps to do here till I can test the acceleration speed.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 May , 2014, 07:52
Hi Gentlemen,

As the blowerclutch, the engineclutch was a double cone frictionclutch, the difference being the size and it was pneumatic/hydraulic operated. I guess you could engaged the clutch at 350 revs, but the wear and tear increases with the speed and inertia forces so we usually started with the clutch engaged. Engaging the clutch at relatively high speed created a lot of smoke allthough nobody knew about the asbestos danger, the smoke could be unpleasant in a confined space.

 Operating instructions state that the clutches should not be engaged when turning the shaft above 350 RPM.  They may be disengaged at any RPM.

The torsional vibrations in the shafting were diffcult to discover as no torsional meter was installed, however the engines were equipped with torsional vibrationdampers up front, but I doubt if that took care of all situations. I have seen a few photos of VIIC shafts breakages which clearly was due to torsional vibration stresses, but if these engines had been equipped with a torsional vibrationdamper I cannot tell.

The GW engines produced strong torsional vibrations in the crank shafts in the following RPM ranges: 260-290 and 360-450. The vibration dampers reduced them almost completely. The operating instructions say, that in case of damper failure, it must be removed (contrary to the MAN dampers, those in case of damage don't have to be removed) and the critical RPMs have to be passed over.

Some of the U-Boats were equipped with the Diesel Engine Torsional Vibration Indicator System. For the details see:
http://uboatarchive.net/DesignStudiesTypeIXC.htm
section S65, page 30.

--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2014, 09:13
Maciek.
It is always good to have a statement confirmed, you are an expert for finding written confirmations. The torsional vibration dampers varies in design, as your info on the GW and MAN engines mention. One is f.i.  mechanical, the other is hydraulical. I believe for the earlier boats they had a torsional vibration meter fitted. I cannot remember we had any. In the 1930 years it was not common to carry out relative complex torsional vibrations calculations for shaft systems, so I guess you had a torsionalmeter to monitor same. But as I said, there have been VIIC shaftbreakages due to torsional vibration stresses and may be they started to make more complex  torsional vibration calculations after that and installed a better tailormade vibration damper at a later stage. Just a theory from my side. The Rooths blower created torsional vibration as well and the drive had another mechanical vibration damper. After the war torsional vibration calculations became mandatory for all seagoing vessels and has to be submitted to the classification societies for approval. The barred rpm range varied considerably between a 6 cylinder and a 9 cylinder engine (IXC) as well as to which inertia masses you connected E-motors propeller etc. so you can not put up rpm valid for more than one cylinder- and mass configuration.
You mainclutch operatings instruction fit very well with my experience, but I would`t like to use 350 rpm as a standard. The wear would require frequent adjustments and even renewal of the friction layer.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 23 May , 2014, 11:00
Just out of interest, what type of torpedoes have you used with Kaura?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2014, 13:28
Mark
Torpedoes were a bit far away from my responsibility so I am afraid I cannot give you much info. We were training on using the LUT torpedoes but as the Germans had stored and left a huge amount of the ordinary "workhorse" torpedoes in  Norway, I believe some 1200, we were put up for using those. I cannot remember the the type no. I believe Maciek knows more on this than I do.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 May , 2014, 18:06
Hello Mr. Tore,


On Plate 17 there is a valve with a "T" as normal, and a line with a bubble in the end of it.  I can not find this valve in the symbol page?  Can you identify this valve and how it functions?


Photo attached....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2014, 02:32
Don.
I cannot remember the symbol so I have to try to figure out. The valve you have marked is the air blow stopvalve for the regulating tank 2 port. stb has the same. These  stopvalves are used for all the MBTs but then the housing contains a checkvalve as well.  Below is a photo of airblow hull stopvalve MBT 4 stb. For the regulating tanks I guess they look similar except the checkvalve is removed. I assume these valves  should be able to be locked open so may be the symbol indicate a lockingdevice.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2014, 03:27
Hi Gentlemen,


according to the Technisches Hilfsbuch für den Gebrauch in der Krietsmarine, this is symbol means plombierte Ventile, that is sealed valve. I must admit, that I don't understand, why sealing hull valve for blowing regulating tank. In case of Tauchbunker it is obvious - to prevent accidental blowing the fuel. It should be the same case for the regulating and reserve fuel tank 1 - but it is not.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2014, 06:04
Maciek.
I guess plombiert could mean the valve is locked in a position f.i. either open or shut. The valve arrangement is not only fitted on fuel ballasttanks but on several tanks having a blowing arrangement including MBT 3. I believe normally the ballast tanks blow valves were in a locked open position, for those to be carrying fuels the valves were locked in shut position in both cases the plombierung means locked in the position required. For reliefvalves f.i. we very often use the expression plombiert which actually mean putting a lead seal on the lock to the valve to ensure no unauthorized person change it. The authorized person can brake the seal and adjust the valve to any value. I don`t think the VIIC valves had a lead seal,  though ;D but an ordinary lockingdevice to prevent any accidental change.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 May , 2014, 11:14
A "plombiertes Ventil" should be a safety valve.


In Abhängigkeit von der Federauslegung kann der Ansprechdruck von Sicherheitsventilen in einem gewissen Bereich eingestellt werden. Der vorgegebene Ansprechdruck wird erreicht, indem über einen Gewindeeinsatz die Federvorspannung beeinflusst wird. Die Stellung der Vorspannung wird z. B. über eine Kontermutter gegen Lockern gesichert. Die Einstellverschraubung wird mit einer Haube verschlossen. Als Maßnahme gegen unbefugte Änderung der Einstellung wird diese Haube mit einer Plombe gesichert.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 May , 2014, 13:56
Mark
Exactly! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 May , 2014, 14:21
Currently my calculation gives a thrust force of 20,001.42 lbs (88,970.75 N) for a single propeller of the Type VII at 470 RPM, 1400HP and 17.7kn - does that sound OK?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2014, 14:30
Hi,



A "plombiertes Ventil" should be a safety valve.


In Abhängigkeit von der Federauslegung kann der Ansprechdruck von Sicherheitsventilen in einem gewissen Bereich eingestellt werden. Der vorgegebene Ansprechdruck wird erreicht, indem über einen Gewindeeinsatz die Federvorspannung beeinflusst wird. Die Stellung der Vorspannung wird z. B. über eine Kontermutter gegen Lockern gesichert. Die Einstellverschraubung wird mit einer Haube verschlossen. Als Maßnahme gegen unbefugte Änderung der Einstellung wird diese Haube mit einer Plombe gesichert.


Not any valve, secured with the seal? This part of text from Wikipedia describes (in my opinion) safety valve, whose overpressure setting is secured with the seal agaist accidental change.
--
Regards
Maciek



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2014, 14:36
Currently my calculation gives a thrust force of 20,001.42 lbs (88,970.75 N) for a single propeller of the Type VII at 470 RPM, 1400HP and 17.7kn - does that sound OK?


Each main thrust bearing can transfer up to 10,000 kg (22046 lbs) of thrust. So it looks ok.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 May , 2014, 14:41
Quote
This part of text from Wikipedia describes (in my opinion) safety valve, whose overpressure setting is secured with the seal agaist accidental change.


Yes, that's what it describes. Sure, any valve could be sealed.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 May , 2014, 14:46
Currently my calculation gives a thrust force of 20,001.42 lbs (88,970.75 N) for a single propeller of the Type VII at 470 RPM, 1400HP and 17.7kn - does that sound OK?


Each main thrust bearing can transfer up to 10,000 kg (22046 lbs) of thrust. So it looks ok.


--
Regards
Maciek


Thanks, this whole ship propulsion stuff is a lot like the thing with the chicken and the egg. Each time you find a way to calculate something you find out that you need another thing that might need the other etc.  :o

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2014, 15:03
Currently my calculation gives a thrust force of 20,001.42 lbs (88,970.75 N) for a single propeller of the Type VII at 470 RPM, 1400HP and 17.7kn - does that sound OK?


Each main thrust bearing can transfer up to 10,000 kg (22046 lbs) of thrust. So it looks ok.


Thanks, this whole ship propulsion stuff is a lot like the thing with the chicken and the egg. Each time you find a way to calculate something you find out that you need another thing that might need the other etc.  :o


Can you briefly describe, how you calculated thrust force?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 May , 2014, 16:04
Can you briefly describe, how you calculated thrust force?



There are several ways that I've found how to do it… and I am not happy with any of them  :(  - I'm searching since weeks for this stuff but haven't found anything better so far.


The most primitive is just a rule of thumb used by normal boat users:
For a good propeller the rule of thumb is:
HP * 20 = Thrust in LBS
would be:
1400 * 20 = 28000 lbs


well… I guess it's clear that this is nonsense


Next thing is the "pullard boll" (boat/propeller is fixed in the water and does not move)


thrust = 11.87 * (SHP * DiameterOfThePropellerInInches)^0.67 (power of 0.67)
would be:
11.87 * (1400 * 63.779527559124)^0.67 = 24631 lbs


Next estimation is (SI units):
(BrakePower * 0.5) / BoatSpeed*0.95    (0.5 is estimation of Propulsive Efficiency which is a bit low as it can be usually 0.5-0.7)
would be:
(1400*745.6998 * 0.5)  / (17.7 * 0.51444) = 57326 N or 12887 lbs


This is also nonsense because it uses the speed of the boat which is not correct, the correct calculation would use the speed of advance of the propeller


What I currently use is:

LBP (Lenght between perpendiculars at the water line) = 62.27 meters
B (Beam - I ignore the saddle tanks) = 4.7 meters
T (draugth) = 4.74 meters
Displacement = 769
Density (of Water) = 1025
StandardTon =  1016
RPM = 470
HP = 1400
VS = 17.7 kn (speed of the boat)


Volume = Displacement * (StandardTon/1000)*(1000/Density)
Blockcoefficient = Volume / (LBP*B*T)
PropulsiveEfficiency = 0.836 - (0.000165 * RPM *  Volume^1/6)      (An estimation by Henschke, 1965)
WaveFraction = (BlockCoefficient / 2) - 0.05        (Taylor)
VA = VS - (VS * WaveFraction)      (speed of advance of the propeller)
Watt = HP*745.69987158227
VA = VA * 0.5144444  (convert to meter per second)


Thrust Force = (Watt*PropulsiveEfficiency) / VA = 88970.76 N = 20001.42 lbs


usually you would also add the Coefficient of hull efficiency (close to 1) to the calculation…


HullEfficiency = 0.98


Thrust Force = (Watt*PropulsiveEfficiency) / HullEfficiency*VA = 90786.48 N = 20409.61 lbs






Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 May , 2014, 23:07
Gentlemen,


I'm have been looking at the valves for a few hours and I see the following:


D1 = HP hull valve + non-adjustable check valve
D2 = HP hull valve + non-adjustable check valve
D3 = HP hull valve
D4 = HP hull valve + non-adjustable check valve (per Mr. Tore's photo)
D5 = HP hull valve + non-adjustable check valve


My understanding of a non-adjustable check valve is the device will allow the medium (in this instance air) to flow in one direction.


My understanding of a hull valve is it is generally used in the full on or the full off state.


Then I reviewed the symbol section of the Skizzenbuch and seen a little ball on the valve wheel handle???  Could the drawing simply be indicating when there is a line with a ball on the end of it that this is a HP hull valve.  This is different form the valve handle on the Q Tanks...


See the drawing:


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 May , 2014, 02:35
Hi Don,
Then I reviewed the symbol section of the Skizzenbuch and seen a little ball on the valve wheel handle???  Could the drawing simply be indicating when there is a line with a ball on the end of it that this is a HP hull valve.  This is different form the valve handle on the Q Tanks...


You are on good track. In fact, all hull valves were fitted with the ball - I have marked them on the bottom part of attached drawing. But the symbol for such valve is quite different - see top part of attached drawing.

Generally - this ball is the part of identification system, which should allow distinction of various type of valves in poor light conditions.


Short description:
Quote
Further identification is provided at handwheels on valves.  Wheels for hull closures all have a large ball cast on the rim.  Valves for seawater lines are balanced cranks with straight handles.  For fuel oil, balanced cranks with tapered handles are provided.  Lub oil handles are five-sided.  Fresh water and hydraulic system valves are five-clover type.  Compressed air system valves are circular, with the rim slightly raised above the hub, with three spokes, and with an oval rim section.  The exhaust gas blow system valves also have three spokes, but the rim is greatly offset from the hub, and the rim is a flat oval.  Emergency vent valves have three spokes, a U-section rim and a hand grip.  Hand gear for vent valves has similar wheels with five spokes.  The main H.P. blow valve handwheel is a large flat wheel with five spokes.  The main H.P. blow valve handwheel is a large flat wheel with five spokes, and the main L.P. blow valve is similar, with three spokes.  Positions of cocks are indicated by grooves on the end of the square stern head.
http://uboatarchive.net/DesignStudiesTypeIXC.htm


--

Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 May , 2014, 02:47
Mark,
thank you for your explanaintion.


--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2014, 01:18
Mark.
Sorry I have been traveling for a couple of days and have not been able to respond. I believe you have to get the modelbasin towing graphs in order to get an accurate input you for your game, it could exist some place in Germany. However the speed/ output relations have so many variables and would f.i. change according to the condition of the hull (fouling) often related to days at sea, weather and sea. If you want to vary the prevailing circumstances in your game, you need a lot of info which I doubt exist for a VIIC. I assume the designed max load of  the thrustbearing could give a clue if all conditions were ideal, calm sea, clean hull, draught and trim etc. which hardly exist,  as you mention thrust cannot generally be empirically  transferred into speed.
In the Uboat information effective July 15, 1940, translated by Maciek there is a table put up at page P 14, Section I General. where outputs related to dieselengine / E-motor revs are put up under two conditions A and B; I cannot find the definition for these conditions, but if we assume A is the optimal and B is the a realistic unfavourable condition, you should have the same rule of the thumb input as the crew would have, may be that would be the easiest way, remembering that the revs is not necessarily identical to the output of the engines, which f.i. could be overloaded at the revs stated.
Tore
   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 26 May , 2014, 01:37
Hi Tore,

In the Uboat information effective July 15, 1940, translated by Maciek there is a table put up at page P 14, Section I General. where outputs related to dieselengine / E-motor revs are put up under two conditions A and B; I cannot find the definition for these conditions, but if we assume A is the optimal and B is the a realistic unfavourable condition, you should have the same rule of the thumb input as the crew would have, may be that would be the easiest way, remembering that the revs is not necessarily identical to the output of the engines, which f.i. could be overloaded at the revs stated.

Trim condition A - Tauchbunker 2, Tauchbunker 4 and Regelbunker 1 empty.
Trim condition B - Tauchbunker 2, Tauchbunker 4 and Regelbunker 1 filled with fuel.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2014, 02:33
Maciek.
Thanks, you always are able to put up written facts. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 May , 2014, 03:17
Don.
Hullvalves. Generally, as Maciek explained, the valve handle or wheel has a cast ball and is usually indicated as a dot or dots on the valvesign handle. The valve sign having a line and a circle I guess, as Maciek found out, is a "plombiert" valve, not necessarily a hullvalve, which I believe can be secured in a certain position. Technically this can be done in several ways f.i. like a counternut or counterhandle. The individual blowing valves are vital, but not always easy accessible and should be in a fixed secured position according to the CO order. Normally for the MBTs this would be in an open position. When MBT 2 and 4 are used as fuel tanks the valves should be secured shut. You shall find this arrangement on all MBTks including 1,3and 5 even if these tanks cannot carry fuel. In addition you shall find the same arrangement on the hullvalves for emergency airsupply and divers airconnection shown on the systemsketch but not allways installed on the VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 26 May , 2014, 11:08
However the speed/ output relations have so many variables and would f.i. change according to the condition of the hull (fouling) often related to days at sea, weather and sea.


There is a rule of thumb for fouling and different sea routes. I need to get a convincing ideal state with calculations first. But even if my thrust calculation seems to be correct (all publications I've found use it) it seems to work for a static condition only (boat has reached maximum possible speed for this engine setting) and not while accelerating.  :-\
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 May , 2014, 21:12
Hello Mr. Tore,


Trim Condition B (main ballast tanks and main ballast and reserve fuel oil tanks filled with fuel oil increased load).

I have a lot of assumptions before the questions...  If my assumptions are totally wrong, then I need to be corrected.  I am in the learning process and definitely need guidance and will not take any offense...

With this additional weight, the boat is setting lower in the water.  This is verified by the Information Manual for the Type VIIC.  The turning radius is wider and slower because of the increased drag introduced by lowering the hull.

One would think that the boat would have no problem diving since it weigh was increased.  However, since D2, D3, and D4 are filled with fuel oil which weighs 13 percent less than water.  It looks almost impossible to get the boat to submerge.

D1             30.7 - M3              Trim Condition B
D2             22.6 - M3                      22.6 - M3
D3             47.75 - M3                   47.75 - M3
D4             26.6  - M3                     26.6  - M3
D5             25.15 - M3

Lets say 1 M3 = 1 metric ton

Total     =  152.8 tons                    96.95  - tons    (96. 8 *  13% less weight FO  =  12.6 - tons)
                  -12.6 tons
Total      =  140.2 - tons

They add about 5 tons of additional supplies, which even lowers the boat further and decreases surface performance even more.  With the supplies The total weight increases.

140.2 tons + 5 tons = 145.2 tons

In normal Trim Condition A the ballast weight would be 152.8 tons and it achieves neutral buoyancy and dives using the Regulating Tank 2 for adjustment.

Regulating Tank 2 has a total capacity of 15.2 M3 /tons
[/size]to be continued....

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 May , 2014, 21:14

In Trim Condition B the weight is 145.2 tons,  or 7.6 tons less; my assumption is that the Regulating Tank 2 has the capacity to achieve neutral buoyancy and dive under these conditions.


[/size]If I haven't got things totally screwed up...

[/size]Q1.  Did the U-Boat you served on run in a Trim Condition B (fully loaded)?
[/size]Q2.  How did the weight effect the draft, generally how much lower was the boat in the water?
[/size]Q3.  With the fuel oil in the ballast tanks, did that change the handling characteristics when submerged?
[/size]Q4.  A basic fuel oil question - as fuel oil is consumed by the diesel engines is the depleted tank area pumped   with water at 87% to keep the boats weight in balance?  Tanks with compressed air would affect the boats weight and neutral buoyancy?
[/size]Q5.  Fuel oil floats on water; are the internal fuel oil storage tanks pumped with water as the oil is being taken from the tank?

[/size]Please feel free to add any additional wisdom,

[/size]Regards,
[/size]Don_

[/size]I don't know why i have the [size]??? [/size]
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2014, 00:04
Don,

One would think that the boat would have no problem diving since it weigh was increased.  However, since D2, D3, and D4 are filled with fuel oil which weighs 13 percent less than water.  It looks almost impossible to get the boat to submerge.

Only D2 and D4 were used as fuel oil tanks. So weight difference between A and B trim condition would be only 6,4 ton

Q2.  How did the weight effect the draft, generally how much lower was the boat in the water?

The KTB for U-604's 1st patrol:
Quote
28 August, 1942, 04.20:
"During the pursuit, at the suggestion of the Engineering Officer, converted
main ballast and reserve fuel oil tanks 2 and 4 for use as ballast tanks. The
remaining fuel oil, 1 ton, was transferred from the ballast tanks to the regulating
and reserve fuel oil tank. At the same time the negative buoyancy tanks were blown.
Thereby gaining about 1 knot. With the high enemy speed of 16 knots these
measures were decisive."

http://uboatarchive.net/KTB604-1.htm

There is a book "U-Boat 977 The U-Boat that Escaped to Argentina", by
Heinz Schäffer, where is described a pursuit for a tanker, then it is said:

Quote
"All our blowers and compressors are screeching for all they're worth—we keep
on blowing our diving tanks every five minutes, for we have to keep as high
above the water-line as we can, since the higher we are the faster we go.
True, the increase in our speed's only fractional, but it is an increase."

(this description is not technically strict, but it shows the idea)

Q3.  With the fuel oil in the ballast tanks, did that change the handling characteristics when submerged?

There should be no difference.

Q4.  A basic fuel oil question - as fuel oil is consumed by the diesel engines is the depleted tank area pumped   with water at 87% to keep the boats weight in balance?  Tanks with compressed air would affect the boats weight and neutral buoyancy?

All fuel oil tanks (except regulating tank 1) are water-compensated. Regulating tank 1 - as filled with the fuel oil and air - would affect weight of the boat.

Q5.  Fuel oil floats on water; are the internal fuel oil storage tanks pumped with water as the oil is being taken from the tank?

Yes, internal tanks are also water-compensated. See the plate:
http://uboatarchive.net/U-570Plate10.htm

I don't know why i have the 

You are probably using some external editor, which uses its own tags, and then you copy and paste the text into the web browser.

--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 May , 2014, 01:25
Q2.  How did the weight effect the draft, generally how much lower was the boat in the water?

It is generally hard to say without knowing the construction displacement and exact shape of the hull. But when I approximated the U-Boat hull by a cylinder and assuming the surface displacement of 769 ton, the change of draft between the condition A and B would be few centimetres.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 May , 2014, 07:08
Don, Maciek.
I am just back from 3- days travelling with limited access to the net, sorry for not answering and thanks to Maciek for the correct answers. A few reflections on the external ballast /fueltanks. We did not use the mbts 2 and 4 as well as the regulating/fuel tanks as bunkertanks a lot . The reason was that we used the VIICs more as a coastal submarine ( a long Norwegian coast up to the Barents sea, having easy access to fuelingstations contrary to the German long warpatrols which even force them to use milkcows. We used the external fuel/ballast tanks occasionally for training only.
Watercompensating. Having watercompensated fuel tanks is giving an extra benefit by eliminating the free surface effect as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 27 May , 2014, 20:32
Just in case that someone wants to know more details about the effect of hull fouling - this old 1952 document shows a lot: https://darchive.mblwhoilibrary.org/bitstream/handle/1912/191/chapter%202.pdf?sequence=9
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 May , 2014, 05:14
Next version of my engine simulation which prints acceleration over time now - I think it is almost OK (except that it is a little bit too fast at max) - seems acceleration fits to what Tore said.


http://www.hessburg.com/downloads/Engine2/Engine2.html
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2014, 05:58
Mark.
Amazing! One question, as you are using the parameters primarily in the SI system why do you have a bmep in psi? I cant get the bmep figures to match the bmep.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 May , 2014, 06:13
I'm sometimes using formulas with non SI inputs. But I've used psi when I wanted to compare the results (while using the Type IX engine settings) with the one on page 10 of this document:http://www.uboatarchive.net/DesignStudiesTypeIXC.htm
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2014, 06:24
Mark.
I am modifying my post
Come to think of it. The figures recorded ( bmep of 6,8 psi ) could match to average  bmep in the SI system (bar sq.cm) of the GW engines without Roots blower connected, I don`t have the figure at very low revs, however the MAN engine at 1/10 load  and 218 rpm has a bmep of 24 psi.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 May , 2014, 19:15
Sorry for late reply, I was offline because the router died.
I've used the MEP to compare it to the data of the Type IX. The printed MEP is based on the calculated torque and the cylinder data. It was extremely close to the IX engine when I've tested it with the IX data. I don't know if it currently prints out the correct values maybe I mixed up units during recent changes but I think it should be correct. Will take a closer look at it when I'm not tired ;-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 May , 2014, 21:47
Hello Mr. Tore,


Again some basic questions on soundings, venting, and test piping ....


Q1.  What is soundings?  Do they take a stethoscope and listen for a tank to hisses or hear drips in the compartments?


Q2.  Fuel oil tanks generally are full of fuel to start, then water gets pumped into the bottom which forces fuel oil out the top.  On plate 8 and 8a, there are vent lines at the top of each tank that feeds into a measuring bucket.  What are they measuring?


Q3.  On Plate 8 and 8a, there are lines at the bottom of the tanks that feeds up to a collection funnel and it looks like it's dumped into the ocean.  Why are they doing this?


Q4.  I can't figure out how the 3 way flooding cock with lateral inlets works on Plate 8a.  photo ttached...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 May , 2014, 00:10
Mark.
 I have slept on your bmep in psi and guess related to the 48,5...SHP the low figure is OK. I have never reflected over or noticed it takes only 48,5....SHP for each engine, thus  a total of only 97,...SHP to push a VIIC through the water at 6,2 knots, slightly more than 1/3 of the max speed.
The US figure on a  9 cyl transferred to a 6 cyl and with Roots blower at max load, I assume would be approximately:
Max cont. 1346 SHP,460 rpm,115 psi bmep, 3/4 load 1086 SHP, 126 rpm, 95 psi bmep, 1/2 load  720 SHP 383 rpm, 72 bmep  psi, 1/4 load 361 SHP, 295 rpm, 45 psi bmep, 1/10 load  (being the lowest output they registered ) 144,5 SHP, 218 rpm, 24 psi bmp.
I do not know where they got the figures. You can not transfer the load figures based on a IXC directly to a VIIC as the hull size and lines are different, but may be it could give an indication.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 02:11
No, you are right something is wrong.  :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 May , 2014, 02:14
Don.
 Q1 Sounding is measuring quantities of liquid in a containers or tank. It is done in several ways like oilchecking on you car using a dipstic. Some tanks the VIIC engineroom are equipped with a kind of dipstick. Q2. The fuel/ ballasttanks have a different system based on smaller pipes,cocks, funnels and a graded container inside the pressurehull , see discussion page 46-47 on this thread .Q3  When you are fuelling, the fuel force the seawater out of the tanks and you monitor the waterlevel by the pipe going almost to the bottom of the tank by the valves ( cocks) on the top of the tanks outside the pressurehull. As soon as fuel is flowing out of the valve (cock) you stop fuelling and prevent fuel spills and as the checkpipe stop some 10 cm above the end of the compensating pipe some compensatingwater residue is left in the fuel/ballasttanks.. I have discussed the whole system on page 47 and 46 on this thread.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 May , 2014, 02:29
Hi Don,

some time ago, Tore described this system here:
http://models.rokket.biz/index.php?topic=921.msg12479#msg12479

Q1.  What is soundings?  Do they take a stethoscope and listen for a tank to hisses or hear drips in the compartments?

The term "Sounding" is quite misleading in this context. The German, original term is "Peil-" - that means gauging, indicating, or probing.
Simply - Peilleitung - installation for measuring the amount of fuel in the fuel oil tanks (internal as well as external).

Q2.  Fuel oil tanks generally are full of fuel to start, then water gets pumped into the bottom which forces fuel oil out the top.  On plate 8 and 8a, there are vent lines at the top of each tank that feeds into a measuring bucket.  What are they measuring?

See Tore's explanation.

Q3.  On Plate 8 and 8a, there are lines at the bottom of the tanks that feeds up to a collection funnel and it looks like it's dumped into the ocean.  Why are they doing this?

These lines are used while filling the tanks with fuel oil. Initially, the tanks are filled with water. Then, trough the fuel oil transfer lines the oil is pumped. These fuel oil transfer lines have their outlets at the top of the tanks, so the fuel is gathered in the upper part of tanks, while the water is forced out through the lines, you are asking for. The crew member is watching the funnel at the upper deck - if from the lines outlet start leaking fuel instead the water, it means, that the tank is filled with fuel and the pump is turned off.

Q4.  I can't figure out how the 3 way flooding cock with lateral inlets works on Plate 8a.  photo ttached...

Based on Tore's description, some time ago I have prepared some drawings, which can illustrate the process of fuel oil amount measuring.

fot 1.jpg - forward bulkhead of the U-570 control room with visible fuel oil probing lines.
fot 2.jpg - forward bulkhead of the U-995 control room with visible fuel oil probing lines and collecting bucket.
fot 3.jpg - control valve of the probing and venting installation in the control room of U-995
rys 7.png - probing of the internal fuel tank - equalising the pressure
rys 8.png - probing of the internal fuel tank - measuring the amount of fuel


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 03:01

The term "Sounding" is quite misleading in this context. The German, original term is "Peil-" - that means gauging, indicating, or probing.
Simply - Peilleitung - installation for measuring the amount of fuel in the fuel oil tanks (internal as well as external).



Peilen is a pretty unusual word for that esp. "Peilleitung" which I've never heard before - but the german word for the oil-level dip stick is "Peilstab" or more common "Ölmeßstab" hence it makes sense that they might have used it during that time.
From the logic of the word it should be used like you said to read the amount of fuel from a nonlinear scale.
But the word Peilung and peilen is mostly used for bearing and targeting and for understanding something - "I don't peil it" means "I don't understand it" - "I have no Peilung" is "I have no idea"
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 May , 2014, 03:52
Mark,


The term "Sounding" is quite misleading in this context. The German, original term is "Peil-" - that means gauging, indicating, or probing.
Simply - Peilleitung - installation for measuring the amount of fuel in the fuel oil tanks (internal as well as external).



Peilen is a pretty unusual word for that esp. "Peilleitung" which I've never heard before - but the german word for the oil-level dip stick is "Peilstab" or more common "Ölmeßstab" hence it makes sense that they might have used it during that time.
From the logic of the word it should be used like you said to read the amount of fuel from a nonlinear scale.

Term "Peilen" is commonly used in the  Tauchvorschrift.

But the word Peilung and peilen is mostly used for bearing and targeting and for understanding something - "I don't peil it" means "I don't understand it" - "I have no Peilung" is "I have no idea"

You are right. The most common (today) usage is as bearing.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 04:53

Term "Peilen" is commonly used in the  Tauchvorschrift.

I guess the usage was dropped quickly within the last decades. Actually I can't remember someone saying that. But a quick search shows that some people still use it today. (but much more people use prüfen, messen or kontrollieren). The word Peilleitung is even more rare, just 28 results with google and I think of those only one was a real hit (about a Peilleitung in an oil tank)
I really never heard that word before today. It's funny to learn something about my own language on an english speaking forum.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 May , 2014, 05:13
Maciek-Mark.
You are much better with organising the paperwork Maciek, thanks. We use the word Peilung  Norwegian peiling just in the same way as the Germans. When it comes to larger amount like KM3 and oceandepth we use the word, sounding, like echolot sounding.
Some time ago I got a board, I guess from Maciek, showing the relation between rpm and speed for a VIIC together with the previous figures it might be of some help for checking the output, rpm, bmep and speed relations graph.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 05:15
I think the HP is possibly too low - But I've used the data from Maciek's picture:


http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=5034;image (http://models.rokket.biz/index.php?action=dlattach;topic=921.0;attach=5034;image)


and when the line get's interpolated it just has so little HP at 180 RPM - the lowest data I've used from Maciek's picture is 158 HP at 256 RPM


(http://www.hessburg.com/downloads/HPuncharged.png)




Anyway the RPM of the propeller is what's used to calculate the trust so it does not affect the speed of the boat in my simulation.
The only effect it has is (if the resulting HP is wrong) is the time how long it takes to spin up to those RPMs.


I've just found out that the torque on his document does not fit to the other data of the RPM and HP:


3456 Nm at 180 RPM should be 118.44 HP which makes much more sense
6810 Nm at 256 RPM should be 244.84 HP instead of 158


at 390 and 470 RPM both curves give pretty similar results


So my guess is the RPM/HP data on the document is not correct.


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 May , 2014, 06:09
Mark.
I see, however when you are running the engine at very low outputs I guess the graph would be unreliable as the heatlosses of the engine becomes an increasingly and very large  proportion of the  bhp so I guess you can`t just interpollate the graph  down to 0 output. ( at 0 bhp you would would require a certain indicated hp just overcome the mechanical and thermodynamical losses to get the engine idling).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 09:44
Low RPM are not that important for me anyway.
But for the 180 RPM (which I need for KF) the HP or the MEP must be wrong on Maciek's data.


When looking at the data of the Type IX from this page 10 of this website: http://www.uboatarchive.net/DesignStudiesTypeIXC.htm


490 RPM - 2470 HP
480 RPM - 2320 HP
470 RPM - 2170 HP
426 RPM - 1630 HP
383 RPM - 1080 HP
295 RPM - 542 HP
218 RPM - 217 HP


Recalculation this with propeller law is pretty close:



490 RPM - 2458 HP
480 RPM - 2311 HP
470 RPM - 2170 HP
426 RPM - 1593 HP
383 RPM - 1174 HP
295 RPM - 536 HP
218 RPM - 216 HP


So when I do the same with the Type VII engine based on (uncharged) roughly 341 RPM (511 HP) from Maciek's data I will get


KF 180 RPM = 75 HP
LF 275 RPM = 268 HP
HF 340 RPM = 506 HP


now based on 470 RPM and 1400 HP:
GF 435 RPM = 1109 HP
AK 470 RPM = 1400 HP
480 RPM =1491 HP
490 RPM =1586 HP


So the calculation based on the propeller law for KF 180 RPM 75 HP is somewhere in the low middle of what the RPM-HP and MEP-HP data shows (50 HP and 118 HP).
The lowest data I've used is already wrong (158 HP at 256 RPM - it should be more like 216 HP for 158 RPM)
I guess the best is to "fix" the low RPM data with data calculated with propeller law and to stop thinking about it ;-)
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 May , 2014, 11:52
Mark.
This sounds like a better solution and bmep would be adjusted to more familiar values.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 May , 2014, 18:56
Tore, I need a way to convert diesel fuel (in kg) to liters. But I have no idea about the diesel fuel used by the Type VII during war. Do you have a rough estimate?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 May , 2014, 23:45
Hi Mark,
Tore, I need a way to convert diesel fuel (in kg) to liters. But I have no idea about the diesel fuel used by the Type VII during war. Do you have a rough estimate?


Have you seen this: http://www.fischer-tropsch.org/primary_documents/gvt_reports/USNAVY/usn_187_45.htm


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2014, 00:00
Mark
I believe the German WW2 Navy had a special specification for the  submarine fuel. During WW2 most of the fuel in Germany would be synthetic fuel made from brown coal. There are several processes which are used. My guess would be for the navy a so called hydrogeneration process was used I, believe a common process is called Bergius process (Kohleflussigung.) I still remember the smell as it had a high degree of aromatic content.  A typical specific gravity of such fuel would be in the range 0.85-0.885. This is an assumption from my side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 30 May , 2014, 14:21
Thanks.


Do you know if there were different types of compass repeaters on the bridge? One source says the destroyed one on the picture would be a pressure proof U-Boat compass, but I never saw one like this one on pictures.






Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 30 May , 2014, 14:41
Do you know if there were different types of compass repeaters on the bridge? One source says the destroyed one on the picture would be a pressure proof U-Boat compass, but I never saw one like this one on pictures.
Check out this thread:
http://models.rokket.biz/index.php?topic=1088.0
I'm not sure if these repeaters are for helmsman or they are repeaters for bearing (navigational) purposes.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 May , 2014, 21:25
hello Mr.Tore and All,


I believe I have a basic understand of how the Header/Buffer tank works... 


1.  Heated water is pumped from the diesel engines and through the pressure hull to cool the exhaust mufflers.  Then the heated water is directed to the buffer tank and is channeled to the RFO tanks, the overflow pipe (which looks to dumped into the sea).  I believe the goose neck pipe is to provide air equalization in the tank.


2.  I had a problem with the lack of a closed pressurized tank.  The amount of water pressure provided to the RFO tanks is the result of the height of the water column form the deck of the Winter Garden to the level of water in the tanks.  I guess it's really ingenious; as the tank's water level rises the water pressure becomes less (self regulating).


3.  When the U-Boat submerges, the external tanks are open to the sea through the buffer tank pipe and as professor Maciek point out to me awhile back; the internal and external pressure is the same with an open tank.  The internal tanks are protected by a closed hull valve and should not see the external pressure.


I do have a question about the buffer tank.  the 4th pipe to the right looks like an arrow pointing down.  What is this?


I will post a drawing...


as always any comments are highly appreciated...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 May , 2014, 21:38
If the U-Boat is configured to use the RFO tanks and fully loaded with fuel, is there a sequence of which tanks are used first?  From Plate 9 it looks like fuel oil can be taken from any external or internal RFO tank.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 00:03
Don.
Compensating water headertank.
I Guess you got it OK. The headertank in the towercasing is always topped up by the attached colingwater pumps when the main engines are running and the head never exceeds the head corresponding to the watercolumn from the bottom of the tanks to the top of the waterlevel in the headertank even being submerged as the footvalves in the saddle tanks are valves which can only be placed in two positions, either to the bottom of the tanks or to the sea. We discussed this detail some times ago and Simon made one of his marvellous drawings of the system see drawing below. As you see the downpointing arrow is a drain. The fuel can indeed be taken from any fueltank and I don`t remember we followed any strict sequence, but as usual there was a communication between the engineers and the officier responsible (in our navy No 1, in the German navy chief engineer) for the trimcalculation as to which tank would be most convenient.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 00:31
Mark.
Compass repeaters on the bridge.
Sorry I was not very much involved in the compasses and I cannot remember which type of compassrepeaters which were on the bridge. I guess Macieks link can give a clue if not, I am sure there are a lot of clever guys out there having done some research on the matter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 31 May , 2014, 06:08
Some changes. RPM now closer to what I wanted to set them. Added faked cavitation (was too complicated to do it right) - overall the acceleration is slower now. Please tell me how the acceleration (and final speed per RPM) looks for you now.  :)


http://www.hessburg.com/downloads/Engine3/Engine3.html
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 07:25
Mark.
It is much better, however I cannot figure out the specific fuelconsumption. At these revs and the Roots blower disengaged, I should assume it would be more like max. 200 g/bhp hour rather than 415 g. The acceleration time 0 to 6.8 knots in  9 minutes astonish me based on my feeling, but I guess it is probably OK. so I should n`t worry.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 May , 2014, 10:43
Gentlemen,


I have been looking at Plate 13 and the cooling water flow.  It looks like plate 13 does not agree with Plate 13a and 13b.  Was plate 13 drawn wrong?


See the attached drawing...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 11:06
Don.
Your observation is correct. It is a mistake in this particular drawing and the stb enginepump , the reserve coolingwaterpump and the coolingwater handpump shall all have a connection to the crossover seacoolingwater suctionpipe. Plate 13 has a mistake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 31 May , 2014, 14:53
Hi Tore

I was just checking our cooling piping of U-1308, and I noted I have missed two things:

The Pressure Gage between the Aux CW Pump and the manifold,
And the Compressed air chambers between the CW pump and manifold.

Where would the Pressure Gage be located?
What do the Compressed air chambers look like and size?

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 15:28
Simon.
I guess plate 13 is a bit misleading. I don`t think it is a compressed airchamber in the line it is rather the airvessel on attached pistonpump driven from the engine, see drawing below. The pistonpump has such airvessel as a buffer to ease the pressure pulses from a reciprocating pump, not needed for a centrifugalpump. The manometer could be the one up on the instrument panel front top of the engines, showing the cooling waterpressure to the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 31 May , 2014, 15:31
Mark.It is much better, however I cannot figure out the specific fuelconsumption. At these revs and the Roots blower disengaged, I should assume it would be more like max. 200 g/bhp hour rather than 415 g.



It's both for for both engines but only written on the first one. I've just multiplied it by 2 for the display



The acceleration time 0 to 6.8 knots in  9 minutes astonish me based on my feeling, but I guess it is probably OK. so I should n`t worry.
Tore



If you think it's too slow then I need to change it. But thrust is pretty low at these RPM.
When I get rid of one of my new faked stuff then the acceleration curves for KF, LF, HF, GF & AK look like this, are they better?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 May , 2014, 23:14
Mark.
I am afraid you cannot multiply the specific fuelconsumption for two engines, as it is specific per bhp per hour thus has nothing to do with the total bhp as the fuelconsumption.
As to the acceleration, you are right, the thrust is pretty low for a fixed propeller at low revs and as my remark is based on feelings I don`t think you shall change it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 01 Jun , 2014, 19:40
I guess you misunderstood me?

The fuel consumption is based on the data of the curve "fuel consumption per hp" - it's calculated for one engine and this result of a single engine is then multiplied by 2 because two (almost identical) engines are running.


It's not like bhp = 100, 100*2 = 200, 200*fuel consumption@200
It's like bhp = 100, fuel consumption=100*fuel consumption@100, fuel consumption*2
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Jun , 2014, 22:42
Hello Mr. Tore and All,


I have a question about Regelbunker RFO tank 1 in the saddle tank...  Since this tank does not have a pipe from the header/buffer tank to provide a water replacement for fuel taken from the tank.  Is this tank only a storage/transfer tank and not capable of being a direct fuel source for the diesel engines?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2014, 22:57
Mark.
Sorry I misunderstood.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2014, 23:32
Don.
Yes and no. It is a non watercompensated tank, but can be used as a direct source as the other tanks. However normally it is no bunkertank in direct contact with the engines as the fuel supply pipes end in the "day tank" a double settlingtank above the engines. You top up the daytank from the fuel tanks, let the fuel settle for a while so possible impurities and water can be drain while running the engines from the other tank where the fuel has already settled.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jun , 2014, 22:21
Hello Mr. Tore and All,


Now on to the Diesel fuel system...  I believe I'm close to understanding some of the functionality.  I will attach a fuel flow from Plate 9.  However, as usual I have a few questions:


Q1.  There seems to be no fuel level control in the Gravity Tank that's mounted above the walk-way between the engines.  How do they know when the tank is full, and which valve would they normally use to shut off the flow of fuel?  The same with the Collection tank except fpr the goose neck over flow spout.


Q2.  The 4 pipes coming from the gravity tank go to a collector and then to the Collection tank (I believe this tank us below the metal walking deck).  Should all 4 pipes go to the collection tank.  I would think that 2 of the pipes would be for settlement and water draining?


Q3.  I'm not exactly sure about valve "e" the change over cock with central passage.  I know it allows fuel to enter the what looks to be a separated gravity tank.  When it's feeding the other side with the drain and tank for the Junkers compressor, I'm not sure about the 2 lines going to the gravity tank.


Q4  The small bypass line on the fuel pump...  this line has a safety valve to open if the pressure gets too high.  How will this ever work because there is a huge bypass line on the outside of the pump?


Q5.  It was stated in one of the manuals that if one of the fuel pumps failed, then the Aux. Pump could be used in it's place.  If this happened, was there the possibility to fix or replace the fuel pump?  With the Aux pump providing fuel for one of the engines, would not the gravity tank stop getting fuel?


I guess that's my quota of questions for today...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2014, 00:42
Don.
Q 1 There are two sight glasses each for port and stb up front of the settlingtanks. Q 3 Cock "e" shut the fuelsupply to the settlingtanks and is shown in shut position on plate 9.
Q 2 Fuelcollecting tank has nothing to do with the fuelsupply to the engines it is merely a collectingtank for the fuel drain and overflow pipes from the settlingtanks, filters,pumps etc . Fuel supply from the bunkertanks to the distribution box is drawn OK, from this box the supplyline goes to the distribution selector cock "e" which has 4 positions: A. shut to the settlingtanks and engines as shown on plate 9. B ,the unusual, daytank shut and fuel goes straight to the fuel supplypump on the engines,C topping up port settling tank and supply to the engine supplypumps from stb. settling tank and D, topping up stb settlingtank and supply to the engine supplypumps from port settling tank. See drawing below.  Q4 The plate 9 shows more a MAN arrangement than  a GW engine. On the GW engine the engine driven fuelsupply pump is up front of the engine. The "huge" pump bypass as you express it is normally shut and is only used when something is wrong with the pump. The relief valve has a normal dimension don`t get confused, look at the photos on the front of the engines.
Q.5 I am not sure if I understand your question right. If you mean the HP fuelpumps on the engines, the engine had to stop and a spare pump fitted, routine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jun , 2014, 00:54
Hi Gentlemen,

Q.5 I am not sure if I understand your question right. If you mean the HP fuelpumps on the engines, the engine had to stop and a spare pump fitted, routine.

I believe, that Don is asking about auxiliary lubricating oil pump - but it is only used while taking fuel oil on board.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2014, 06:09
Don.
If you assume the aux. luboil pump should be used as Maciek says, I am afraid you got the fuel transfer system screwed up. All the fueltanks are as you know seawatercompensated except the F.O. regulating tanks. This means the F.O. bunkertanks are always under the head of the watercompensating tank high up in the towercasing ( not the wintergarden as you have mentioned) assuring the settlingtanks are having a supply pressure at the tank of 2- 3 m.W.C. This means that no fuelpump to transfer the fuel is necessary. The waterpressure derive from the attached cooling waterpump on the engines and the outlet to the headertank is at the exhaustmufflers in the casing. The headertank is always topped up in this way when the engines are running and normally you top up the engineroom settlingtanks when the engines are running. If you for some reason would like to transfer fuel from the FO tanks when the main engines are not running, you use the electric driven reserve coolingwater pump or even the handpump to keep the watercompensating headertank topped up giving sufficient head to the fueltransfer. As to the reserve fueloil regulating tank, you normally use air under low pressure for fueltransfer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Jun , 2014, 15:23
Tore,

I have rather general question about operation of diesel engines. From the basic experience with car engines I know, that
color of the fumes may indicate some problems with the diesel. For example white smoke can mean leak from the cooling
system and blue smoke - that engine burns the lubricating oil. The black fumes can indicate, that there is inadequate amount
of air to fuel combustion - or to much fuel - for example due to injectors failure.
Do the marine diesel engines behave in the same way? How about GW engines? What kind of problems influence the
color of the fumes? Did you experience some of them? Were there some repairs/adjustments possible while at sea?
I know, that this was not so important while snorkeling,  but when U-Boats cruised most the time on the surface, the machine
crews paid attention to the color of the fumes.

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2014, 16:31
Hello Mr. Tore,


In addition to Maciek's question about the diesel exhaust; did they purposely run a rich mixture while blowing the ballast tanks to provide a layer of un-burned diesel fuel as a means to protect the tank's lining from corrosion?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2014, 20:27
Hello Mr. Tore,


Now I'm interested....


"Tore"
A.   shut to the settlingtanks and engines as shown on plate 9.
B.   the unusual, daytank shut and fuel goes straight to the fuel supplypump on the engines,
C.   topping up port settling tank and supply to the engine supplypumps from stb. settling tank and
D.   topping up stb settlingtank and supply to the engine supplypumps from port settling tank

The drawn position of e valve is shut (closed).  If it were rotated 90 degrees where the valve line/separator was not parallel with the tank, then we would have condition B; fuel going straight to the engines?

Now here is where I have a problem; does e valve have more than one activating lever/wheel, etc.? Something has to cause the diverting of the direction fuel can flow.  In the drawing where you are topping up the port side and drawing fuel from the stb side, how do you stop the fuel flow into the port side when the tank is full without affection the stb side fuel supply to the engines?

The one possibility I see is using the valve f ahead of the filter to the incoming fuel line. That way the one settling tank supply can be stopped without affecting the other settling tank that is providing fuel to the running engines...

Confused as usual...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2014, 02:35
Maciek and Don
 Running of the GW diesels. As both a car- and GW diesel generally are fourstroke engines, the combustion is pretty much the same. So the colours of the exhaust would be following the same rules. On a submarine however you have a wet sparkarrestor after the silencer which created some white watervapour pretty much like cooling waterleakage in a car engine. A bad atomizing of a fuelinjector or an overload,( lack of oxygen in relation to fuel) created a black exhaust. The exchange of fuel nozzles or HP fuelpumps is relatively simple on a large diesel and was a quick routine job at sea, spare fuelinjectors and pumps were always on board. Contrary to the car engine we checked the combustion in another way. Each cylinder has an indicatorcock e.g. a cock having a direct connection to the combustion chamber, every morning I personally checked the cylinders combustion by looking at the colour of the combustionjet on each and every cylinder. In this way an experienced eye could pick a cylinder not having an optimal combustion. If a further check would be required you could attach an manometer to the cock and check the combustionpressure before carrying out repair. This is a much more accurate check than looking at the exhaust. Black exhaust could be a problem when schnorcheling. Particularly when starting the engine as it was some residue water in the exhaustpipe. This water created a  backpressure in the exhaust pipe which could open the reliefvalve on the exhaustmanifold filling the engineroom with black exhaust, rather unpleasant.
Blowing the ballasttanks by exhaust. I know somewhere in the literature it is mentioned that an advantage of the exhaustblowing was rustprevention of the ballasttanks. We never paid attention to that, in fact the ballastanks were nice and clean painted with a yellow zinc chromate and very little corrosion.  Certainly we would not like to foul up the engine by running the engine with an incomplete combustion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2014, 03:17
Don.
I understand your confusion as the description of the selector cock is incomplete. The supply cock "f" is indeed used for topping up the system. The supply from the bunker fuel tank is much faster that the consumption of the engines so it goes relatively fast to top up the settlingtank and cock "f"cock is commonly the shut off cock for that operation.
A word on "closed" and "shut". In the RN submarine english the word closed is not used, in order to prevent misunderstandings for an important word, shut is generally used.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2014, 23:16
Maciek.
Combustion check.
Perhaps I should mention that in addition to the checks I mention, the GW engines were equipped with individual exhaust thermometer for each cylinder which would register any unormal combustion as well. Proper monitoring of the combustion was important for many reasons and hence the surveillance was good. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Jun , 2014, 02:29
Tore,

thank you for your answers.
When you started diesel engines after submerged cruise (that is when engines were cold) - did you run them for a some time with low load to get them warm gradually (except emergency of course)? I have met following figures: after start about 10 minutes KF, then 5 minutes LF, then 5 minutes HF and so on.

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2014, 05:24
Maciek.
From an ideal point of view it would have been nice to run the engines as indicated by you. However when you surface you normally would like to obtain full buoyancy as quick as possible, particularly at heavy weather and swell. This because the metacentric height change from negative to positive when you break the surface and you are in an unstable situation. Hence you start the engine and run same at the load required for blowing the ballasttanks with a somewhat higher exhaust backpressure rather than an ideal warming up load. Otherwise normal surface cruising, starting with cold engines, we did not use the engine telegraph with strict speed commands, but communicated with the bridge verbally leaving the gradual increase in output to the desire of the engineer on watch, only to be overruled by the engine telegraph if the bridge had to.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jun , 2014, 12:09
Hello Mr. Tore and all,


My observations on Plate 8a (venting, sounding, test piping) are as follows:


1.  Maciek provided an excellent drawings on how to measure the remaining fuel in internal FO tank 1 and 2.  No questions...


2.  I don't see any means to measure the contents of fuel oil in any of the saddle tanks (D2, Regulating and RFO tank 1, and D4) in the Type VIIC.  I believe I seen a drawing from a Type XXIII that had a means to measure the external fuel tank contents.  Am I correct?


3.  D4 has the ability to drain fuel (from the top) into a collector bucket.  Why?


4.  D2 has the ability to drain fuel (from the top) into the FO Collecting tank. Why?


I have a question about the FO Collecting tank.  It looks like there is some type of a collecting valve that permits the input lines to feed the tank.  I assume it is manually or some how opened; it can't just be an open collector?  Otherwise, the measuring gage feeding the collector from D2 would be worthless because the collecting tank has a goose neck vent.


One question specifically for Mr. Tore -  When times were difficult and the captain needed to stretch his fuel oil supply, was the fuel oil in the FO Collecting tank re-cycled and used to power the engines?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2014, 00:29
Don.
Your no 2. question. measuring fuel from saddletanks. I think you have seen some drawings either from the IXC type or XXI. The system works as follows: a relatively small diam. pipe goes almost from the tankbottom to the top. A few cm. from the top is a 3 way selector cock which i believe can be operated from inside which either connect the pipe to the upper part of the tank or to the inside of the pressurehull via a hullvalve to a graded draincontainer. When measuring, you first put the selector cock to a equalizing position e.g. connected to the fluid on top of the tank and let the level stabilize in the small measuringpipe. Then the oil level in the pipe is at the same level as the tank. Then the cock is turned to a measuring position, the connection to the top of the tank is shut and the hullconnection is open. The inside cock is opened and the compensatingwater force the oil contents in the pipe into the measuring container.The hullcock is shut as soon as the compensating water starts to come. The the container has now an accurate oil level measurement of the saddletank which by tables can be transferred into oil volume. I have tried to make a sketch below.
3 and 4. You never squeeze the last drop of fuel into your fuelsystem, f.i when when you want to drain the external fuel/ballasttanks to convert same into just plain ballasttanks all the fuel on the top must be drained. You avoid letting the last drop go overboard and create an oilslick danger, thus you drain the last drops into contaminated oil collectingtanks and containers, not into the bilge.
The VIICs did not have a fuel separator or clarifier only gravity settlings and filters thus we did not use any contaminated fuel from the collecting tank.  We did not worry about environment in those days but the danger of being traced by an oilslick was allways in our heads and great care was taken to prevent fueloil contaminating the compensating watersystem and bilges.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jun , 2014, 10:50
Hello Mr. Tore,


Thank you for your response...


Q2.  I know how it works on the Type IX and XXI, but this is not available in the Type VIIC?


Question about the FO Collecting tank -  How is the collection valve controlled?  It looks like it has to have a shut state, otherwise the pressure measuring gage could not measure the fuel pressure?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2014, 12:01
Q 2. I cannot remember we had this system on the VIICs.
Fuel drain collecting tank pressuregauge. I am not sure I understand the question, I believe the the "valve" is a connection point on the top of the tank receiving the fuel drains by gravity and otherwise having no pressure. Could you explain which fuelpressure gauge you are referring to?
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jun , 2014, 12:51
Hello Mr. Tore,


On Plate 10 left side, there are two sampling pipes from D2 port and stb that connect to a collector (one above and one below).  There is also a measuring device going to the same collector with a valve.  All of this goes into the FO Collecting tank. 


In the other drawings of the FO Collecting from the top on Plate 9, there looks to be a circle with 4 inputs.  If that circle were just an open collection point in the FO Collecting tank, then the measuring device would never be functional because the FO Collecting tank has a goose neck to equalize the tank pressure with the internal hull pressure.


Is that some type of a valve in the FO Collecting tank with the 4 inputs?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2014, 14:14
Don
If I have understood you correct this time, I believe plate 10 shows the compensating water (green) entering the pressurehull via the normal hullvalve a, drains e and d as well as reliefvalve f. then to the inner fueltanks 1 and 2. Before entering the tanks each have a overpressure and underpressure reliefvalve which for tank no 1 has a drain via a funnel to the  (yellow pipe) fuel collecting tank in the engineroom. Se my sketch below.Tank 2 has a similar drain in the control room. Would that be it? I don`t believe it is a valve (or four) on the FO collectingtank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jun , 2014, 17:42
Hello Mr. Tore,


I have marked 2 pipes as the A side and the B side on the drawing as follows:


1.  The B side looks to contain the pressure water from the Header Tank. 
2.  The A side has a collection funnel and drains directly into the FO Collecting tank. 
3.  The FO Collection tank has a goose neck vent to equalize the air pressure in the tank.


If this is the configuration, then I don't understand how the Measuring Container can ever collect anything.


If there is an over pressure event on the B side of the pipe and the over pressure relief valve opens, then the contents goes directly into the FO Collecting tank and nothing would get measured. 


Perhaps, I do not understand the function of the measuring device...


Can you enlighten this poor sole?  Do you have a photo of it?


Kind regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2014, 02:15
Don.
I see you, have mixed up the compensatingsystem with the fuelsounding. There are three ways of measuring the fuelcontent in the bunkertanks. One for the inboardtanks 1i and 2i which Maciek has explained with his drawings. The pipings,containers,valves and cocks can be seen for 1i at the aft bulkhead in the control room and for 2i at the forward bulkhead, pretty much dominating selector cocks (valves). The samples are drained into  rather large containers which used to be removable, today they look like tackwelded into the support and shut by a lid. These containers, which were not marked, and contained fuel, should not be emptied into the bilge but carried and emptied into the measuring container in the engineroom shown on the sketch for the compensating system. After the measuring, the container is drained into the funnel and to the fueloil collector tank. It is hard to see the system on the available photos but I guess you can see the funnels behind some connectionboxes on port and starboard forward engineroom bulkhead.
The saddle fuel/ ballast tanks having checkpipes going almost to the top of the tanks were only checked for compensatingwater at the top and were drained for the F.O.BTKs 2 in the fuel collectingtank in the engineroom and F.O. BTKs 4 in a container in the controlroom.
The third way is that for the F.O. bunker/ regulatingtanks which have sigthglasses next to the sightglasses for the regulatingtanks in the aft end of the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jun , 2014, 15:28
Hello Mr. Tore,


I apologize for asking so many dumb questions...  All I had to do was take a pause and think about the plumbing in my home to understand a little more about water pressure in pipes.  This is a different medium for me where I spent 46 years tracing electrical wires to components on a circuit board or schematic.


Now, I don't have a problem with venting, or sounding (measuring).  Thank you for your patients...


One question...  When a mission was completed, how was the fuel oil collecting tank emptied and cleaned out in preparation for the next mission?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2014, 00:35
Don.
Some times it is easy to get confused when different systems are interfearing, I remember ( some 60 odd years back) when I crawled all over the pipes of the VIICs to figure out how the piping worked with limited access to drawings. To know how at that time was a matter of life and death of 46 men. The VIICs have so many alternatives in the piping systems which some times was a challenge to use to its full extent. Emptying the fueloil collecting tank is one of them. It is a suctionpipe from the collectingtank to a system having hoseconnecting to a pump on shore as well as a valve connection to the suction of the handcooling waterpump which at the discharge side has a hoseconnection to wherever you want, see sketch below. As the discharge side of the handpump could end up in the galley or engine coolingwater system required a certain knowledge by the engineroom crew to prevent disaster or a furious cock on you neck. ;D
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jun , 2014, 10:18
Hello Mr. Tore,


I was wondering why contaminated oil was going to the galley...  Perhaps a chef's salad with a special oil and vinegar dressing???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2014, 12:03
Don.
The coolingwater handpump had many tasks, apart from a possible supply of dirty fueloil to the galley, a more serious task was to pump anticorrosive oil into the sea coolingwater system. As you can see it was a hose connection to the suctionside of the pump were you could connect a hose to a barrel of anticorrosive oil and a discharge via valve D1 to the cooling watersystem (Druckwasser). I am afraid the chef salad was non existent on a VIICs, in that case it would had to be made of seaweed and may be dirty fuel oil did not had to be mixed with vinegar to get the proper dressing for seaweed. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 11 Jun , 2014, 15:19
Tore or Maciek do you have any data about knots at RPM when driving astern?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 12 Jun , 2014, 07:29
Maciek, I guess this was yours? http://sourceforge.net/apps/trac/derleitendeing/wiki


What have you tried to achieve?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2014, 07:33
Mark.
As far as I remember the GW and I presume MAN were converted into non reversible engines as from 1943. Thus the power for going astern was limited to E-motors. The direct reversible diesels I guess could give the same power astern as forward. The propellers would not give the same thrust astern though. I am sorry I have no figures, may be Maciek have some. Generally submarines were maneuvered by E-motors.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 12 Jun , 2014, 07:42
Thanks, I just want to add reversed diesels because it was possible (till 43)… (and subsim players are used to it)



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Jun , 2014, 01:17
Hi Mark,

Tore or Maciek do you have any data about knots at RPM when driving astern?

Unfortunately, I do not have any data about astern drive.

Maciek, I guess this was yours? http://sourceforge.net/apps/trac/derleitendeing/wiki (http://sourceforge.net/apps/trac/derleitendeing/wiki)


What have you tried to achieve?

Well, yes, I have started this project. In the first iteration I have tried to model U-Boat and its dynamics - especially when submerged. I have created (or rather implemented) algorithms for calculating centres of mass and centroids of the tanks (with any amount of water in them), then I have calculated the centroid and centre of mass of the whole vessel, which resulted in the moment of forces. I have also taken into account the rate of flooding and blowing of the tanks. This is was I have achieved. Finally, I wanted to give the operator the control of the whole vital installations of the boat, allowing him blowing particular tanks, shifting water between trim tanks, controlling compensating tanks and so on. All this would result in the position of the vessel in the water and her movements.
The project has been stalled, as I contacted with Captain Jerry Mason and have involved in the translation work. Now I'm doing wide research in the torpedo fire control systems - when I finish it, maybe I will go back to the derleitendeing - now my knowledge is far greater.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2014, 02:17
Maciek and Mark.
You certainly are going into quite a task Maciek and Mark if you are going to incorporate Macieks studies into the game it would be a very demanding play almost like the programmes which are used for training COs and EOs final course before being commissioned. The fruitmachines and similar firecontrol "computers" were very much the first stage of our to days computers without the semiconductor technique. We used rheostats, resistors and capacitors  requiring unbelievable space for a relative simple calculation.
Final question Mark I am just curious, what would you use the astern speed figures for?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 13 Jun , 2014, 08:09
I need them to make the astern speed in the game more correct. Actually any known astern speed at a given RPM would help me to figure it out for all RPMs. Reversed propellers are totally different (hull in the way, propeller efficiency itself, drag when going backwards etc.) - even a rough guess would help me.


Interesting stuff Maciek, details like this won't make it into the first version of my game but I will try to implement it into the later main version which should be much more complex.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2014, 09:10
Mark.
I believe we only used the astern thrust very shortly in following cases: 1. maneuvering alongside, 2.turning on the spot one propeller ahead, the other astern and for 3.emergency braking, in all cases the speed would be of less importance. In cases of diesel reversing, the timedelay, the time to shift camshaft etc., would probably be a more important factor than acceleration or retardation characteristics. A longer operation of going astern I would assume would not be likely and moreover the thrust bearing is only designed for running continuously ahead. Just a few thoughts on the subject as I can`t fully understand the need for the asternspeed. :D
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jun , 2014, 19:03
Hello Mr. Tore,


Things seem to be awfully quiet on the site, perhaps we need some more basic (dumb) questions to liven things up...


To start:


When I read about blowing the ballast most times the documentation only refers to Ballast tanks 1 through 5 and the negative buoyancy tanks.  However, there are two tanks that are not mentioned; the stern and bow buoyancy tanks.  I believe these tanks are open at the bottom with slits, and have a vent valve, and a low pressure air line. They are fully equipped do do the job quite well...


It would seem if there were an emergency dive situation that these tanks would get blown besides running all the un-needed crewmen to the bow of the U-Boat???


Please let me know when these tanks are used for something other than Longitudinal stability...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jun , 2014, 19:12
Hello again Mr. Tore,


There are 2 lubricating oil tanks with a total capacity of 6.5 m3, and a dirty oil tank with a capacity of 0.79 m3.  Where does all that dirty lubricating oil go, certainly not in the much smaller tank?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2014, 00:45
Don.
The bow and stern buoyancytanks are not considered as ballasttanks, if you use the German words for the tanks it literally says watertight fo`csle and watertight stern. They are situated mainly above the normal surface line and the main purpose for the tanks are to dampen the longitudinal pitching of the vessel. They have as you say vents opened locally at the forward and aft torpedorooms. They are normally not taking part in the surfacing of the submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2014, 01:48
Don.
In addition to the tanks you are mentioning there are two  luboil system tanks, port and starboard. May be a short description of how the system works can be useful. Each engine has normally a closed luboilsystem where the system luboiltank (f.i. stb for stb engine) is intergrated. The no 1 and 2  luboiltanks are merely storagetanks. The dirtyluboil tank is pretty much like the fueloil collecting tank taking luboildrains and at the time oil purifier was installed, receiving the oil sludged from same. The tank can be emptied by a handpump on the port aft bulkhead in the engine room as well by a suction hose connection to a shore pump. The system oil tanks port and starboard can be emptied by the electrically driven reserve lub oil pump port fwd  in the engine room or by the a hose connection to pump ashore as well as by the luboil hand pump at stb. fwd. bulkhead in the engine room. Filling the systemtanks  from the luboilstorage tanks can be done by the same pump
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2014, 22:44
Hello Mr. Tore,


I was reviewing information on a web site about starting marine diesel engines...


http://www.marinediesels.info/Basics/air_start_simple.htm


Did the GW and MAN engines have the basic components discussed here built onto the engines for air starting?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2014, 00:55
Don.
The airstarting of the GW engines and almost the same on the MAN was a bit different. Referring to plate 29 below : Each engine had a starting air flask topped up from the HP system. Each cylindercover had a starting air valve which in the starting sequence was engaged with starting cams on the camshaft by a pushrod. The valve had two airconnections, one at the top for pneumatically pushing the starting valve pushrod in contact with the camshafts starting cams. The other air connection is the startingair supply to the cylinder. The starting procedure is done by the starting handle on the maneuveringstand and the mainstarting supply valve having a handwheel ( painted red on U 995). The main starting supplyvalve is opened, starting handle is put in start position , air is admitted to the top of the cylinder startingvalve, pushing the valve rod against a springpressure down to the startingcam on the camshaft. One of the cams is always in a startingair lift(open) position thus admitting startingair to the cylinder and the engine starts to run on air, by the starting valves. As soon as the engine achieve satisfactorily revs you move the fuel handle and fuelrack of the fuelpumps,   admitting fuel to the cylinders and the engine starts to run on fuel. Then you put the starting handle to "neutral" the air on the top of the startingvalve is vented and the spring pushes the valverod up and disengage the connection to the camshaft. As plate 29 shows the system of the direct reversible engine, the real execution of the modified nonreversible execution is slightly different, but the idea is the same.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Jun , 2014, 08:44
Interesting stuff Maciek, details like this won't make it into the first version of my game but I will try to implement it into the later main version which should be much more complex.


Nonsense  ;D  It's much easier to do a lot of this now, at least the basic stuff.


Where can I find info how quickly the different tanks can be filled and how quickly they can be blown?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jun , 2014, 11:20
Mark.
I cannot remember seen any such figures, may be Maciek have an idea. We were more concerned about f.i. diving time rather than surfacing time. Crash diving required a very well trained crew.   With normal preparation and a trained crew you could manage 30 seconds which is pretty fast compared to other similar submarines at that time. I Guess it could be contributed to the relatively large flowarea of the Kingstons plus the permanently submerged hydroplanes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 Jun , 2014, 13:23
OK, I might find a solution to calculate that the diameter of the vents is written on Uboatarchive,net…


Do you remember how much compressed air could be stored?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 Jun , 2014, 13:52
Found it in the manual  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jun , 2014, 14:52
Mark.
3.900 liters at 205 bar/cm2. You didn`t blow the tanks by HP air at depths greater than 14 meters normally only for emergency you are blowing tanks at greater depths. Hydroplanes and speed is a better way of changing the depth, better control and saving of air.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 Jun , 2014, 15:08
But during an emergency situation you can only blow the main ballast tank below the command room right? The other MBTs would be destroyed at higher depths if they would be blown right?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 Jun , 2014, 21:57
We were more concerned about f.i. diving time rather than surfacing time. Crash diving required a very well trained crew.   With normal preparation and a trained crew you could manage 30 seconds which is pretty fast compared to other similar submarines at that time.


My (hopefully not totally idiotic) calculation for the required time to flood the MBT below the command room (when no other tanks are flooded and the boat can still float on the surface) is something like 11.64 seconds
Do you think that could be OK?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 00:33
Mark.
Air blowing.
Emergency blowing is usually done by all the MBTks as it is the differential pressure which counts. As long as the tanks have free access to the sea and you are blowing keeping the differential pressure well below I believe o,6 bar, MBT 3 bar it is OK. As soon as the boat stop sinking and the boat start slowly to ascend, you stop blowing and the air start to expand in the tanks forcing out the remaining water out creating a fairly uncontrolled acceleration ascent which is not desirable except for emergencies.
The total air capacity of 205 bar is sufficient to to blow all the main ballast tanks and reserve fuel oiltanks totalling 155m3 at 40 meters and for the main ballasttanks only totalling 105 m3 at 65 meters. If you end up at 100 meters only 71 m3 can be blown, just to mention a few examples I found in the U boat info (1939) translated by Maciek.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 00:56
Mark.
Flooding MBT 3.
47,7 m3 including venting duct to be flooded in 11-12 seconds seems awfully fast, but with the large Kingstons I guess it could be possible. I never have been experiencing such a test. Both normal diving and particularly crashdiving was done in a more dynamic way using hydroplanes and speed in addition to ballasttanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 Jun , 2014, 01:44
When I use the standard leak formula the result is that the 47 cubic metres of this tank could be theoretically flooded within 2.29 seconds (if the tank would be completely open on top instead of having 2 valves for the air to leave) when the "leak" of a comparable size is at a depth of 4 meters.


My calculation takes the leaving air through the 2 vents into account that's why it's much slower. But 10 seconds fits with some numbers I have read yesterday about flooding a MBT on a "Tauchboot" compared to real modern submarines which flood slightly slower.
Shouldn't the MBTs already have completely filled when you've reached pericope depth? I think the positive buoyancy would be too strong to go that deep that fast otherwise. But that's just my guess…  :)







Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 01:59
Mark.
I believe it is OK. Don`t forget it is not only the MBT 3 vent restrictions, but the fairly long airducts through the saddletanks as well. You would like to have the ballasttanks filled as quick as possible and certainly at periscope depth.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jun , 2014, 10:00
Hello Mr. Tore,


I have a question about grinding (burnishing) the exhaust flapper valve seat.  I have attached a photo from the uhistora web site.


Q1.  I assume this was dome to both exhaust valve seats?
Q2.  They state this was done every 4 to 6 hours?
Q3.  Item 4 in the photo - is this a lever/actuator to start the gringing process?
Q4.  Was there some type of electric motor connected to the shaft to rotate the flapper valve, or was it a motor connected by a machinist?
Q5.  The valve seat that was being burnished (remove carbon build-up) was it a type an lining similar to auto brake lining, metal to metal would not make a good water seal?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 11:55
Don.
The group exhaustsystem consist of two flap valves, the inner which casing is shown on you photo and the outer being in a casing outside the pressure hull just before the silencer. Between these valves is a valve with the branch off to the exhaust blowsystem. The flapvalves have a valvedisc which can be rotated by means of a gearim on the disc which is connected to a wormgear. The inner flapvalve is operated by hand moving the rod seen on your photo, the outer is operated by a pneumatic motor which via rods and bevelgears rotates the wormgear on the outer flapvalve. The valve discs are rotated (in open state)once a watch to prevent carbon deposits on the rotating mechanism. When diving the valves are shut and rotated, thereby grinding the seatings which is conventional. If the valves were leaking we just waited till the water backpressure on the outer flapvalve was some 3-4 m wc giving a better pressure for the grinding. At depth greater the 5-6 m wc the resistance was too big for moving the disc. Between the two valves it is an ample drainage possibility to the bilge. I have tried to make some sketches of the system below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 12:16
Don.
I believe something did go wrong with the first sketch so here is another try.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jun , 2014, 20:23
Hello Mr. Tore,


Since this was a manual job...  Was there a crank or a hand-wheel put on the shaft to grind the inner housing flap valve seat?


In your response...  What does "wc" stand for?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jun , 2014, 21:19
Hello Mr. Tore,


a second question...  The photo from the Spanish site; can you identify items 6, 7, and 8.  Unless my Spanish-English translation really failed me.  I don't believe these items have anything to do with turbocharged gases or the control room.  I believe these lines and valves are on Plate 13 in the engine room...


I posted a part of Plate 13 where these line and valves look to be...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 22:57
Hello Mr. Tore,


Since this was a manual job...  Was there a crank or a hand-wheel put on the shaft to grind the inner housing flap valve seat?


In your response...  What does "wc" stand for?


Regards,
Don_
Don.
WC stands for watercolumn in this case the pressure on the valvedisc caused by the seawater by the distance to the surface. I cannot remember excactly how the wheel / handle was I guess more like a bar.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2014, 23:00
Hello Mr. Tore,


a second question...  The photo from the Spanish site; can you identify items 6, 7, and 8.  Unless my Spanish-English translation really failed me.  I don't believe these items have anything to do with turbocharged gases or the control room.  I believe these lines and valves are on Plate 13 in the engine room...


I posted a part of Plate 13 where these line and valves look to be...


Regards,
Don_
Don.
 I guess a part of your post has disappeared.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Jun , 2014, 00:02
Don.
Referring to your Spanish photo it is not a simple answer because I believe the Spanish explanation is a bit confusing and incomplete. The group exhaust boardcasing consist of several cast steel parts all having watercooled jackets. As these parts are flanged together the coolingwater has to bypass these flanges. This is done by coolingwater bends which you see on the photo. However the coolingwater has to flow for each flanged part: in at the lowest point and out at the highest, which make the piping a bit complicated. In addition to the cooling waterflow you have the main drain from the exhaustspace between the outer and inner group exhaustvalves, further ventingpipes and greasepipe for the valves. I think you have to study the coolingwater plate 13 to follow the flow. I have previously made a sketch trying to explain the system which is posted below. The group exhaust valve watercooled casing is in fact the main engine coolingwater overboard "pipe" as well and as such designed for full max divingpressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 Jun , 2014, 21:50
Tore,


In the german original version of the manual I've found the sentence:



"Die Regelzellen sind angeschlossen an die Fluteinrichtung in der Zentrale…"


which means:


"The regulating tanks are connected to the flood installation in the command room"


But the english translation says:
"The regulating tanks are connected to the drainage installation in control room"


…in the description of the Torpedo compensating tanks Maciek used "drainage installation" for the word "Lenzleitung" which is correct (and the opposite of a "Fluteinrichtung")


Now when looking further into all the info about the different tanks I can't find out any info about how some of the tanks will be flooded (I mean where is the flood vent, where do they take the water from) - is it possible that there is such a flood installation with a common flood vent for the incoming water for these tanks?

- regulating tanks
- regulating reserve fuel oil tanks (when used as regulating tanks)
- Trim tanks (or do the trim tanks use a kind of closed system with a fixed amount of water to pump it around?)


Another question:
The torpedo compensating tanks… in the german version of the manual they write "Die Torpedozellen nehmen das Wasser für den Gewichtsausgleich der Torpedos und Minen sowie das Umhüllungswasser auf" - Maciek forgot to translate the word "Umhüllungswasser" in the english version: "The torpedo compensating tanks are flooded to compensate for the weight of a launched torpedo or mine." - this word is pretty tricky to translate it's like "surrounding water", I guess they mean the water used when flooding the torpedo tubes?


And one more question, how much time does it takes to blow the tanks with the diesel?
Rössler wrote in "U-Boottyp XXI" that it takes 2 minutes to blow the torpedo tubes with air (0.6 atm) - then blowing tanks with the diesel should take a lot of time right?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Jun , 2014, 23:30
Mark. I am not very conversant with the torpedosystem, I never interfered with the torpedo people. We have the same word "Umhullung" in Norwegian and I guess your assumption is correct, you flood the torpedotube, launch the torpedo, the surrounding water is ejected and you compensate for the totalweight torpedo plus surrounding water.
Exhaustblowing of the ballast tanks always seemed to me to take a long time. I Guess I never recorded the time and it varied depending upon trim, exhaustpressure adjusted by the outer flapvalve,weather and how much the ballasttank were blown by air etc.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jun , 2014, 00:29
Mark.
Take a look at plate6 and you shall have a good understanding of the compensating, trim and regulating system. As you say most of the control of this system is situated in the controlroom. It is a very flexible system having its own seawaterconnection with volumecounter in the CR aft stb. Via a number of pipeconnection chests you can flood the tanks directly, or by connection to the bilge (Lenz) pumps. The regulating tanks (and Q tanks) have an inboard venting ending in a muffler down at the bilge, you can see the system with sightglasses clearly on the photos showing the aft part of the attack periscope casing in the aft controlroom. The use of drain in connection with the system is a bit confusing at least for the Europeans. In naval english we use more bilge and bilgepump (Lenzing) rather than drain, as we use drain in the meaning "tapfen".
The trimsystem is a bit different from the regulatingsystem as this is more like a pitching compensating rather than buoyancy compensating as done by the regulating tanks. thus you move the same water from fwd to aft or opposite. Although you have connections so you can adjust the amount of water you can play with.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jun , 2014, 00:36
Mark.
Regulating tank flooding/filling. draining/ empytying.
Below is a a drawing of the floodinginstallation with connection to the various systems.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jun , 2014, 12:44
Thank you! Could you give an estimation in minutes how long it took to blow the tanks with the diesel?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jun , 2014, 13:25
Mark.
Exhaust gasblowing.
As I said the time could vary depending upon how much the tanks were emptied by air, the weather (sea), trim etc. Lets assume the exhaust pressure at the control panel in the controlroom is O,5 bar and the airblown tanks have placed the boat having casingdeck slightly above the sealevel, calm sea and a good trimlevel, thus ideal condition. My guess would be some 10-15 minutes. I never recorded the time so this is pure guesstimate from my side. In a difficult situation or very bad weather you always could sacrifice some HP air to shorten the time subject to the COs judgement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jun , 2014, 13:53
great, that helps a lot  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jun , 2014, 23:31
Tore, do you know what diameter the lines of the compressed air blowing installation to the tanks had (or the inlet openings for that in the tanks itself? Or was that somehow connected to the air vents of the tank?)… I need that information to calculate the time necessary for blowing tanks at a given depth.


The pressure of the air in the air flasks was 200-205 atm - how long could you keep the pressure at 25 atm in the blowing installation? The flasks were at different positions how were they depleted, one by one or all together?


It took about 4 1/2 hours to completely refuel the compressed air flasks, is that correct?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2014, 00:58
Mark.
Ref. plate 17. The Hp air system consist of 12 HP flasks each two flasks connected into a bank thus 6 banks. Bank 1 outside pressurehull, both sides of aft ext. torpedocontainer. Bank 2 .outside pressure hull appr. above the main engines. Bank 3 inside pressurehull both side of PO mess. Bank 4 inside pressure hull port side fwd. torp. room. Bank 5 inside pressurehull stb. side forwd torp room. Bank 6 outside pressurehull one flask inside bow buoyancy tank the other stb. side torp container.
The banks are connected to a distribution panel in the controlroom and then to the various blowing distr. panels as can be seen on plate 17.
The blowing pipes to the ballasttanks are going from the blowingpanels to a NR valve and a hullvalve directly into the tank, not via ventingpipes, see photo below. I don`t have the diameter of the blow line but if you look at the photo I should make a guesstimate of 20-25 mm.
I believe each HP flask has a volume of 325 liters and the E- compressor has a capacity of 6.1 liter/min at 205 kg/cm2, the Junker compressor has a capacity of 8.5 liter/ min at 205 kg/cm2, which should make it possible for you to calculate the time for recharging the air. You could keep the pressure at 25 kg/cm2 as long as your HP flasks had a pressure exceeding that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 13:23
Thanks, maybe one day when I visit U 995 I'll measure it  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2014, 14:16
Mark.
Give her love and kisses from me. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Jun , 2014, 14:20
Hi Gentlemen,

I have not been here for a some time, so I'll try to answer for some questions in one post.

Interesting stuff Maciek, details like this won't make it into the first version of my game but I will try to implement it into the later main version which should be much more complex.


Nonsense  ;D  It's much easier to do a lot of this now, at least the basic stuff.


Where can I find info how quickly the different tanks can be filled and how quickly they can be blown?


We were more concerned about f.i. diving time rather than surfacing time. Crash diving required a very well trained crew.   With normal preparation and a trained crew you could manage 30 seconds which is pretty fast compared to other similar submarines at that time.


My (hopefully not totally idiotic) calculation for the required time to flood the MBT below the command room (when no other tanks are flooded and the boat can still float on the surface) is something like 11.64 seconds
Do you think that could be OK?


When I use the standard leak formula the result is that the 47 cubic metres of this tank could be theoretically flooded within 2.29 seconds (if the tank would be completely open on top instead of having 2 valves for the air to leave) when the "leak" of a comparable size is at a depth of 4 meters.


My calculation takes the leaving air through the 2 vents into account that's why it's much slower. But 10 seconds fits with some numbers I have read yesterday about flooding a MBT on a "Tauchboot" compared to real modern submarines which flood slightly slower.
Shouldn't the MBTs already have completely filled when you've reached pericope depth? I think the positive buoyancy would be too strong to go that deep that fast otherwise. But that's just my guess…  :)

I have also used some standard formulas for a leak into the tank with opened top. As a result I had about 10 seconds for flooding all three main ballast tanks. Taking into the consideration the diameter of the vent ducts, I think it fits into the practical times of achieving periscope depth.

In the german original version of the manual I've found the sentence:


"Die Regelzellen sind angeschlossen an die Fluteinrichtung in der Zentrale…"


which means:


"The regulating tanks are connected to the flood installation in the command room"


But the english translation says:
"The regulating tanks are connected to the drainage installation in control room"

…in the description of the Torpedo compensating tanks Maciek used "drainage installation" for the word "Lenzleitung" which is correct (and the opposite of a "Fluteinrichtung")

Literally translation of the word Fluteinrichtung is flood installation as you said. I have translated it as drainage installation, because in other parts of manual, this system is called either Flut- und Lenzeinrichtung or (more common) Lenzeinrichtung and I tried to keep consistency. This Flut- und Lenzeinrichtung was used to drain bilges and tanks or to flooding regulating tanks, as Tore explained.

As Tore said, the British English term is rather bilge system or bilge pump rather than (as in American) drain/drainage system. You can easily see this difference while reading British report  and ONI report on HMS Graph (or American reports on type IXC and XXI U-Boats). I used rather American naval terms.

The torpedo compensating tanks… in the german version of the manual they write "Die Torpedozellen nehmen das Wasser für den Gewichtsausgleich der Torpedos und Minen sowie das Umhüllungswasser auf" - Maciek forgot to translate the word "Umhüllungswasser" in the english version: "The torpedo compensating tanks are flooded to compensate for the weight of a launched torpedo or mine." - this word is pretty tricky to translate it's like "surrounding water", I guess they mean the water used when flooding the torpedo tubes?

Right you are, my mistake.

Have you seen my document on torpedo tubes?
http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats


Tore, do you know what diameter the lines of the compressed air blowing installation to the tanks had (or the inlet openings for that in the tanks itself? Or was that somehow connected to the air vents of the tank?)… I need that information to calculate the time necessary for blowing tanks at a given depth

The inner and outer diameter of blowing lines are 17 and 20 mm respectively.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 14:37
Have you seen my document on torpedo tubes?
http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats (http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats)



The inner and outer diameter of blowing lines are 17 and 20 mm respectively.



Yes I stumbled upon it yesterday.


Wow, where do you found this information about the diameter?


I'm trying a new calculation for the tanks now based on a paper from 2011 about computer controlled ballast tanks for non dynamic diving (from reading this paper it seems that they haven't introduced this at least till 2011 on submarines).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 14:42
At 25 atm (and 20°C) the mass flow of air into one tank should be 1.41145831051 kg per second  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jun , 2014, 17:07
Hello Mr. Tore,


I have a book "Type VII U-Boat" and it stated the electric air compressor was primarily used while submerged.  That statement looks to be uninformed to me!  First it is noisy and would help the enemy to locate the U-Boat, and would drain the battery.  Just where is the electric air compressor going to get its air supply to compress - from the pressure hull?  And who lives in the pressure hull - People who can be affected by no air and high negative pressure.


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Jun , 2014, 18:51
Don,

I have a book "Type VII U-Boat" and it stated the electric air compressor was primarily used while submerged.  That statement looks to be uninformed to me!  First it is noisy and would help the enemy to locate the U-Boat, and would drain the battery.  Just where is the electric air compressor going to get its air supply to compress - from the pressure hull?  And who lives in the pressure hull - People who can be affected by no air and high negative pressure.

In some cases E-compressor was used while submerged:
Quote
Excess pressure of more than 40 mb is to be pumped off with the electric
compressor, if possible, to prevent carrying away acid when opening the
conning tower hatch.

Tauchvorschrift, paragraph 202

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 19:21
Hello Mr. Tore,


I have a book "Type VII U-Boat" and it stated the electric air compressor was primarily used while submerged.  That statement looks to be uninformed to me!  First it is noisy and would help the enemy to locate the U-Boat, and would drain the battery.  Just where is the electric air compressor going to get its air supply to compress - from the pressure hull?  And who lives in the pressure hull - People who can be affected by no air and high negative pressure.


What do you think?


Regards,
Don_


no idea but my thoughts are:


1. I think the air of the quick diving tank is always released into the pressure hull, so they could compress at least 6.51 cubic meter without reducing the pressure inside the boat below standard atmospheric pressure. Not much but this would be worth 6.5 tons of weight close to the surface.


2. At an altitude of 2000 meters (which is still OK for humans) the atmospheric pressure is 77% of sea level (783.8 hPa) so for the crew itself it would be safe to reduce the pressure to that amount.
The air inside the boat is 391 cubic meter hence 89.93 cubic meters could be compressed which is 449 liters at 200 atm (the total amount of compressed air in the flasks is about 3900 liters at 200 atm)


3. at greater depths the pressure in the boat should increase due to the slightly pressed hull another light amount of air would be available to compress.


I could only imagine that they would do it in case of emergency when laying on the bottom at a great depth with damage to all saddle tanks and in case that the pumps can not overcome the water pressure (no idea how they perform at lets say 200m) - but maybe they could somehow attach the electric compressor directly to the 25 atm blowing system to speed things up?? This device should have more than enough power to do that.


But I guess the stress on the hull would increase with less air in the boat…


…and you would need to put all that air into the boat again before you could open the conning tower hatch


And of course I have no idea and talking nonsense   :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jun , 2014, 22:39
But I would not think this was the primary electric air compressor mode for operation; submerged?  This mode of operation would never replenish the air in all those tanks.  This had to be done while surfaced (I think)!!!


Regards,
Don_


PS


Does anybody have a photo of both Toggle Switch Switchboards (Port and Starboard) of the older style U-Boats?  I'm having some issues determining how the circuitry works with only half the picture (Port side only in the manual).  There seems to be a difference in switches according to the circuitry in the manual, but I want to be sure and not guess. 



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 22:43
Maciek there is another mistake in the manual (possibly at a lot of places):


On page 40 you've translated it to "The highest pressure in the installation is 25 atm"
Correct would be "The highest pressure in the installation is 26 atm" (and for the diesel 1.5 atm)
They've wrote 25 atü - atü is "Atmosphere Überdruck" which means "atmosphere overpressure" and is:


X atü = X atm + 1 atm (or more correct at instead of atm)


You will instantly understand why when you look at the 0.5 atü (1.5 at) pressure used to blow out tanks with the diesel. The 0.5 atm from the english manual would be below the atmospheric pressure and it would not be possible to blow out a tank with that, actually it would do the opposite and work like a drinking straw.
The water pressure at a depth of 5 meters is about 0.5 atm but 1 atm of the atmosphere has to be added which is 1.5 atm hence you can blow out the tanks with the diesel up to 5 meters (depth of the bottom of the tank) which perfectly fits to MBT3 which bottom is approx. 80 cm above the keel at a draft of the boat of 4.74m so it is about 4m below the water surface. So when the tank is empty you still have an overpressure in the tank of approx. 0.1 bar.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 22:45
But I would not think this was the primary electric air compressor mode for operation; submerged?  This mode of operation would never replenish the air in all those tanks.  This had to be done while surfaced (I think)!!!


Yes sure. But it seems they could use it at least to compress some air while being submerged (if that makes any sense at all is a different thing)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2014, 23:23
 Don and everybody.
The E- compressor was used when submerged and not schnorchling mainly to get rid of the overpressure in the boat which always built up. The overpressure started to build up as soon as the tower hatch was shut as the pneumatic motors for the grinding of the group exhaustvalves in the engine room were operated. Depending upon the leakages you could use a awful lot of air and you could get a substantial overpressure. Inboard venting and small leakages contributed as well. If we had time we were running the E-compressor prior to surfacing to to prevent a rapid pressure fall when the tower hatch was opened. Many gauges were influenced by the higher ( and lower) airpressure  f.i. some of the depthgauges and at last but not least the cooks preparation for the meals were highly influenced as higher pressure increased the boiling temperatures. Yes people on board a submarine got to learn the practise of the thermodynamics and particularly the Boyle-Mariottes Law.  ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jun , 2014, 23:30
I've read in "the death of the uboats" that at least one commander died when opening the hatch after (I think emergency) surfacing, he was blown out of the boat like a rocket.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2014, 23:56
Mark.
True, we always had a man with a firm grip on the COs legs in those cases we had to surface without pressure equalizing. And Mark, running the E compressor at 200m would be a bit risky. The E-compressor was depending upon a seacooling system consisting of inter stagecoolers, water jackets, pumps and valves. we never operated or opened the seavalves at great depths as blowing a gasket or getting a crack at depths like 100 m would be troublesome.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 23 Jun , 2014, 00:07
But what if you would lay on the ground at 200m and the boat has negative buoyancy (or dead engines) for some reason? Is the situation then die or blow and die?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Jun , 2014, 00:22
Don.
In desperate situations you try anything, and improvise. When I studied submarine technique a class ahead of me disappeared with the loss of HMS Affray. I remember the old Commander E`s wise words as the tabloid press screamed about building a multimillion submarine escape tank: why don`t use the money to improve the crews skill to run a submarine rather than how to escape or handle impossible situations.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Jun , 2014, 09:23
Hi Gentlemen,

But I would not think this was the primary electric air compressor mode for operation; submerged?  This mode of operation would never replenish the air in all those tanks.  This had to be done while surfaced (I think)!!!

Well, generally you are right. First of all, in the book "Type VII U-Boat" are some errors. The sentence saying about usage the compressor while submerged has sense only in the context explained above, or can be treated as another author's mistake.

Maciek there is another mistake in the manual (possibly at a lot of places):


On page 40 you've translated it to "The highest pressure in the installation is 25 atm"
Correct would be "The highest pressure in the installation is 26 atm" (and for the diesel 1.5 atm)
They've wrote 25 atü - atü is "Atmosphere Überdruck" which means "atmosphere overpressure" and is:

Mark, you are right. I had seen the difference while translating the text, and even had a discussion with Jerry, how
to handle designation of units (in English there is no simple corresponding term for atü unit). And finally, this matter
was forgotten.
I will correct errors you have spotted.

I've read in "the death of the uboats" that at least one commander died when opening the hatch after (I think emergency) surfacing, he was blown out of the boat like a rocket.

Here is interesting discussion on this topic:
http://uboat.net/forums/read.php?20,62642,62699#msg-62699

The E-compressor was depending upon a seacooling system consisting of inter stagecoolers, water jackets, pumps and valves. we never operated or opened the seavalves at great depths as blowing a gasket or getting a crack at depths like 100 m would be troublesome.

That's interesting notice indeed, Tore. I have checked, that cooling system of E-Verdichter was tested up to 15 atü.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Jun , 2014, 10:22
Maciek.
Testpressures and deep diving.
It was common, anyhow in my peacetime, not to go deep ,say down to 100m, without shutting off for deepdiving (and depthcharging), meaning boardvalves and branchvalves to systems not absolutely necessary. Air compressor was not considered being absolutely nessesary at these depths when we are talking about routine dives. In emergency situations you always evaluate all options to be taken, balancing risks against benefits. Laying stuck at 200m I guess is one of the situations where "the devil eats flies"you try everything.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 23 Jun , 2014, 18:42
Maciek,


I think something is wrong with your translation of the main drain pump:


"The drain performance by // and -- mode are similar up to depth of 57 meters.  At greater depth the performance by // mode decreases strongly.  It is practical to switch to the - - mode at a depth of 50 meters.  During trials, by connecting the auxiliary trim and drain pump (358 liters/minute) in parallel, drain performance at depths greater than 50 meters is increased by 40%."


Correct would be something like this:


"The performance of // and -- mode will cross on the graph at a depth of 57 meters. At greater depth the performance decreases strongly when operating in // mode. In practice you should switch to the -- mode at a depth of 50 meters. By the hook-up of the auxiliary trim and drain pump (358 liters/minute) in serial to the suction and pressure lines of the main drain pump, the drain performance at depths greater than 50 meters was increased during trials by 40%"


But it's possible that I just don't understand it all all  :)
Anyway "Praktisch ist ab … überzugehen" is clearly a directive.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Jun , 2014, 23:18
Hi Mark,

"The drain performance by // and -- mode are similar up to depth of 57 meters.  At greater depth the performance by // mode decreases strongly.  It is practical to switch to the - - mode at a depth of 50 meters.  During trials, by connecting the auxiliary trim and drain pump (358 liters/minute) in parallel, drain performance at depths greater than 50 meters is increased by 40%."


Correct would be something like this:


"The performance of // and -- mode will cross on the graph at a depth of 57 meters. At greater depth the performance decreases strongly when operating in // mode. In practice you should switch to the -- mode at a depth of 50 meters. By the hook-up of the auxiliary trim and drain pump (358 liters/minute) in serial to the suction and pressure lines of the main drain pump, the drain performance at depths greater than 50 meters was increased during trials by 40%"


But it's possible that I just don't understand it all all  :)
Anyway "Praktisch ist ab … überzugehen" is clearly a directive.

Right you are, these pumps should be connected in serial.

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 23 Jun , 2014, 23:27
great - helping to find mistakes is fun :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 Jun , 2014, 02:33
Tore, this simple formula is from scientific paper about submarines - you can estimate the reduction of buoyancy caused by the outside pressure compressing the hull:


B0 = buoyancy due to vehicle displacement at zero depth
B = current buoyancy due to vehicle displacement at a given depth
Z = depth


B = B0*(1 - ((0.015 / 300) * Z))     (I always use more brackets than necessary  ;) )


So at a depth of 200 meters the buoyancy is reduced by approximately 1% (8.65 tons)


What have you done to compensate that? That's almost 18.5% of the volume of MBT3. Was the lift force of dynamic diving still enough? (I haven't calculated the dynamic forces yet)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Jun , 2014, 03:05
Tore, this simple formula is from scientific paper about submarines - you can estimate the reduction of buoyancy caused by the outside pressure compressing the hull:


B0 = buoyancy due to vehicle displacement at zero depth
B = current buoyancy due to vehicle displacement at a given depth
Z = depth


B = B0*(1 - ((0.015 / 300) * Z))     (I always use more brackets than necessary  ;) )


So at a depth of 200 meters the buoyancy is reduced by approximately 1% (8.65 tons)


What have you done to compensate that? That's almost 18.5% of the volume of MBT3. Was the lift force of dynamic diving still enough? (I haven't calculated the dynamic forces yet)

Mark, in Tauchvorschrift is the following paragraph (no 181):

Quote
Because the boat loses volume at greater depth, it must be made lighter by timely pumping (for type VII boats approximately 1 ton per 100 meters).  It is appropriate to pump out a greater amount, because the boat will be heavier by the accumulating leak water anyway.

http://uboatarchive.net/DivingRegulations.htm

Compensating buoyancy reduced by 2 tons (at 200 meters) could be easily done by means of regulating tanks (of total capacity 24,6 ton).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jun , 2014, 09:55
Hello Mr. Tore,


Is there a master switch for the battery compartments in the Galley and the Officers sleep area?  Do you have any photos?


Did the battery compartments have any type of warning system about pressure or chlorine gas sensors? Was there any means of exhausting the chlorine gas while submerged?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jun , 2014, 00:12
Don.
I don`t have any photos of the automatic batteryswitches they were placed in special small rooms as indicated on the below sketch. The batteries and battery compartments were checked twice a day taking acidgravety and water topping. Looking at plate 18 you should be able to figure out the battery ventilation system which did not have any possibility to get rid of the chlorinegases while submerged except rising the schnorchel. However we had a lime installation as can be seen on plate 26. As to automatic chlorine warningsystem I can`t remember we had anything like that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jun , 2014, 09:32
Thank you Mr. Tore for the information regarding my question about the batteries...


Today, I am just about finished working on the circuit schematic for the Rotary Switchboard.  However, I'm just not completely sure about  the Field 1 and 2 hand-wheel in the center.  I believe these wheels are independent and move separately and the normal Low speed for the outer speed hand-wheel is to the left (see attached photo LOW/Niedrig is to the left).  The photos I have from U-995 shows the wheels in the center and to the right.  I guess museum traffic and people turning the Hand=wheels makes for my confusion because I don't believe they are in the shutdown position.


Does anyone have information about the smaller hand-wheel that is used to select Field 1 or Field 2 on the speed controller?  Where is the normal shutdown, not active position?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jun , 2014, 02:31
Mark.
Submarine displacement at great depth.
When you use formulas like you found involving displacement figures, depth and hullcompression you have to be aware of that the submerged displacements figures is a bit different to a surface ship. At great depth the compression of the pressure hull (displacement) is the only component which is influenced by the submergepressure. The steel, wood and other solid meterial like the superstructure,  is not significantly influenced by the waterpressure at 200 meter. Thus the diminishing of the displacement is only that of the internal volume of the submarine which you could estimated to 450-500 m3. Your 865 tonnes (1 % 8.65) is based on the totalt weight of the submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 27 Jun , 2014, 09:38
Thanks Tore, calculating it with 450 tons is still more than twice as much as the historical documents says (2.25 tons per 100m instead of 1 ton). In this case I trust the older data.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 30 Jun , 2014, 08:50
Tore and Maciek, I'm still not certain how large (effective) the air & water openings really where - I wonder if the numbers on uboatarchive take grille into account.


Could you open the kingstons or the air outlet venting valves partially? Or were they all like flaps only?


(still have no idea how a kingston really works)


BTW:
I've made a miniature "MBT" of a water bottle and recalculated openings so that the volume and openings fit to MBT3 - did that just to get a totally rough idea how fast this thing could really fill. …sure pressure difference is different and several other effects so it's worthless but it gives at least some really rough idea. This thing filled up pretty fast - 12-13 seconds (and the lowest depth is just the depth of the bottle) - If someone wants to have some fun with water: necessary holes are (I think) like 7.6 * 7.6 mm and 2.2 * 2.2 mm for a 1 liter bottle  ;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 30 Jun , 2014, 09:35
Hi Mark,

Tore and Maciek, I'm still not certain how large (effective) the air & water openings really where - I wonder if the numbers on uboatarchive take grille into account.

I have no other numbers than these on the uboatarchive.net. The MBT 3 as well as RFO&MBT 2 and 4 have no grille. MBT 1 and 5 have rather flood slots than grille.

Could you open the kingstons or the air outlet venting valves partially? Or were they all like flaps only?

The flood valves were normally opened while at sea, so you don't need consider them partially open.
The vents construction is visible on this plate:
http://uboatarchive.net/U-570Plate28.htm
I think, that only vents of MBT 1 and MBT 5 could be consider partially opened.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2014, 10:51
Mark.
Further to Macieks remarks. The Kingstons working is based on the travelling nut principle. For MBT 3 the threaded valve spindles are supported in two location- and turningbearings, the spindle ending through a pressure stuffingbox in a square end in the CR where a removable crank turned the valvespindle. On the spindle is a travelling nut fixed to a yoke moving the Kingston outwards as indicated on my sketch below. You could in fact open it in any position but as Maciek says it was normally not done. The saddletank Kingstons are operated in the same way as can be seen on plate 28 but open inwards. The MBT 3, 2 and 4 vents were directly operated by handle and rod movements and are either shut or fully open as can be seen on plate 28. All the moving parts inside and outside the pressurehull have grease connections.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 30 Jun , 2014, 12:07
tanks err thanks  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 30 Jun , 2014, 12:37
Tore, I think you mentioned the "jet effect" somewhere in this thread. How does that work?
When the tank if full of air and the boat raises the water pressure sinks so air will leave the tank through the flood port, is it just the power of the leaving air that makes such a huge difference when surfacing?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2014, 12:55
Mark.
I should probably mention that it is only the forward double Kingstons on MBT3 which is operated by a yoke as seen on my photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2014, 13:10
Mark.
It is a combination of air forcing the water out of the ballasttanks at an increased speed as the air expands due to falling ambient pressure rather than anything else. However an increasing jet of water out of the Kingstons (and floodgates) is created as well. I emphasize this is absolutely not the way of surfacing, It is a waste of air and partly an uncontrolled surfacing but of course it could be a show off. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 01 Jul , 2014, 12:06
Thanks, I've added the jet effect.  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2014, 01:26
Mark.
Watergauge regulating tanks, f.o. reg. tanks.
Below is an image of same ,stb. aft controlroom, same on port side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2014, 06:54
Mark.
Regulating tanks reduction of volume.
Below is a red mark off showing the MBT3 airduct  passing the regulating tanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 04:35
Tore,


The 4 main ballast and reserve fuel tanks 2 & 4 stb & bb… could those operated together only? In other words: were they like a single tank split into 4 tanks sharing a single vent?
And if so, what about their kingstons? http://www.uboatarchive.net/U-570Plate28.htm (http://www.uboatarchive.net/U-570Plate28.htm) shows a cross section area of flow of 3.167 m2, this is much larger than for all other tank so I guess it's for all 4 tanks together and the kingstons were opened together only?



Edit: 2 & 4 shared a vent via a duct on each side between Spant 41 & 42 - hence the pressure of air in both tanks was always equal…
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 04:53
…when looking at your model of the Kaura I see 6 Kingstons for MBT3 and 4 on each of MBT 2 & 4. The Kingstons look almost identical from their size. I think the 3.167 m2 cross section area of flow are for each of the pairs 2 & 4 (6.334 total for MBT 2 & 4 stb & bb together)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 05:58
The Type VII manual shows the distance to the center of mass for all of the tanks. But the center of mass is not static, it can move - what position (horizontally) should I use for placing the tanks based on the information of the manual? (I've tried to estimate geometrical position of the center of mass (of the tanks itself) for each tank before, but this is extremely intuitive and just a rough guess)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2014, 09:23
Mark.
The venting of the MBT 3, 2 and 4 port and stb is arranged as seen on the sketch below. 2 and 4 port and stb are opened simultaneously. MBT3 port and stb likewise.Thus you may say they are operated as one tank, however each tank venting can be shut off by a valve next to the tank in case of a possible damage to the venting duct.  I believe the flood area indicated on plate 28 is the total. If you calculate the tank volumes in relation to the floodareas you get for the MBT 3 total volume 47,7 m3/ floodarea apr. 2,76 m2 = 17,28. For the saddle ballasttanks 2 and 4 total volume 49,6 m3/ floodarea 3,167m2= 15,66. Be aware the MBT 2 port and stb has a venting in the aft end for residual venting. When diving or surfacing at an angle you shall have difference in pressure in the ballasttanks as they are at different depth.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 09:43
OK, then I'll keep them as 4 different tanks because of the pressure calculation and because each tank venting to the duct could be shut off.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2014, 09:47
Mark.
The tanks distances from the mass center.
I am not sure I understand your question properly. Do you want to have a pitch calculation based on each tank onboard, not only ballast tanks, like a calculation for the total trim at a given situation as a leakagecalculation for compensating in the event of a leakage (damage) flooding of a compartment? In that case I am afraid it would require a lot of calculations with many variables.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 10:58
My ballast tank calculation already has about 1500 lines of code.  :)  When I feed it with the correct data then I get the current trim & pitch of the boat "automatically", it recalculates the waterline, remaining air and the evolution of pressure in each tank 50 times per second based on the depth of each tank and the areas of the flood openings and air vents. (and a lot of more necessary things) My calculation script is based on a scientific paper about computer controlled ballast tanks for submarines. The resulting forces act on the boat in a similar way like the calculated buoyant forces due to displacement of water do (the boat is split into parts and I calculate buoyancy for each of those parts separately) - these forces (and thrust of the propellers, the lift of rudders and diving planes at their positions and also all forces due to different drag in all directions and rotations) act on the center of gravity of the boat causing a torque and acceleration.
What I need is the correct position of the tanks itself. (the position of their own center of mass on the horizontal axis when completely filled - during the calculation I only move the tanks center of mass on the vertical axis, I don't take the actual shape of the tanks into account because that's almost impossible)


I could add any tank if I want to but currently I want to use only those:
MBT 1-5
watertight stern and bow
regulating tank 1 & 2
regulating cell 1 & 2
trim cell 1 & 2
negative buoyancy 1 & 2
torpedo compensating tanks fore and aft


For example the manual says the MBT3 is located 2,10 meters in front of the center of mass of the boat - for me that sounds like they are talking about the center (of mass) of MBT3 - what I need to know is the position of the center of mass of the boat used for calculating those positions of the tanks in the manual (it's not clear because the boat could be trimmed etc.) - once I have the "correct" positions then the amount of errors should be as small as possible and I could start creating a virtual "lt. commander Tore"  :D  and train him to trim the boat (when the positions of the tanks are too different then it will be harder for my virtual Tore to do his job or in worst case the volume of the trim tanks could be too low to compensate the wrong positions of the tanks). Sure this all won't be 100% correct but it is closer to the real thing than any other submarine simulation game and it works "automagically" without fakes.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2014, 11:18
Mark.
Impressive! Belonging to a generation which was depending upon smell,noise,feeling and experience rather than anything else such computercalculations is really an Utopia. I am afraid we had a far less sophisticated way of doing things and I see your need for inputs. Sitting with my late Saturday drink I guess I shall wait till tommorrow before I shall see if can be of any help at all. Computergames are definitely not my speciality.  ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Jul , 2014, 12:17
I think it's still utopia or experimental because the paper is from 2011 and they wrote that today when dynamic diving in shallow waters is not possibly (for example in missions to bring in divers close to a target or whatever it could be) they still need the person who does the job based on his experience and mostly on an intuitive feeling only.
But maybe some rough computer control for the tanks is common today? I have no idea but I can't imagine it's not.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2014, 03:16
Mark
Reading the manual, it seems to me the figures given are for a standard of contents of all  tanks (stated in the manual) and two MBTconditions A all MBT empty  giving the submarine a reserve buoyancy of 155 m3. and B MBT 1,3, and 5 empty and MBT/FO tanks 2 and 4 port and stb full with dieseloil giving the submarine a reserve buoyancy of 155-49,6= appr. 105 m3. The pitch calculations are based on these two conditions using the pitch moments based on the various MBTs calculated mass centers distance from the submarines calculated mass center without giving the specific location of the center. I don`t believe you shall find any accurate calculated location of the submarine masscenter`in the manual as this book is meant as a manual for the people on board using a fairly rough calculation as usual for the 1940- 1945 technology. Sorry for not being able to give a better :( help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 06 Jul , 2014, 04:16
Well, then I use the geometric center (on the horizontal axis) - at least on the surface it seems that this also is the center of gravity (otherwise the boat would not lay in the water like it does) - submerged the position of the conning tower might change that.


Do you have a detailed picture of a kingston? Or of the venting valves? I want to know how open these things really are when opened. (if I can use the whole area in the calculation).


My boat still dives extremely fast. But maybe that's correct and I just have to add the human factor? I know there is a description on the diving procedure on uboatarchive, but could you please tell me an estimation how much time the necessary tasks took? (open vents and kingstons for example - in my simulation they they can be just open or shut, maybe I should add the necessary times for opening to the calculation (even if it's just 0.5 seconds) with a growing flooding and venting area while opening. Any information with estimated times is useful - like estimations how long from the order to dive till the first vent is open (based on a perfect crew at their best performance), how much time till the next one will be opened (really at the same time?)
The "diving procedure" on uboatarchive http://www.uboatarchive.net/KTBNotesDiving.htm (http://www.uboatarchive.net/KTBNotesDiving.htm) says the tanks were flooded while the crew was still preparing the bridge for diving but my calculated uboat sinks that fast that the hatch of the conning tower reaches the water surface after 11 seconds (after vents opened).


Also the "diving procedure" does not mention MBT1 at all, what about MBT1 when was it flooded?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2014, 06:38
Mark.
The best Pictures of the Kingstons and vent to my mind are those on plate 28. As can seen they give a good opening with a fairly low restriction. Thus I think you can use the full floodarea may be - 5 to 6%. As you know there are normally two ways of diving. The conventional way and the wartime crashdiving the latter require a well trained crew. Conventional dive is the most common. The boat is in a E-motor mode and presumed MBT 2 and 4 port and stb in ballast mode. Upon the command dive,dive,dive! the vents for MBT 5, 3, 4,2 and residue venting 2 are opened. 2,4 and 3 vents are very quickly fully opened by a swift pull down of the ventlevers in the control room.  5 and residueventing 2 take a bit longer time may be 4-5 seconds as they have to be turned open. After some 5-6 Seconds the vent for MBT 1 is opened taking again some 4-5 Seconds. The boat should now have a bow down angle about 5-8 degrees, ideal: tower windeflector should pass the watersurface simultaneously with the stern. This manoeuvre is carried out in order to prevent the propellers and rudder to brake the surface. However at an angle exceeding 8 degrees you get a substantial difference in pressure between forward and aft MBTs. and it gives a crazy feeling to see from the controlroom the large engines  hanging "high" up in the aft end.
The crash diving is an emergency maneuvering and can be risky, thus requires a fairly high degree of training. You have several crash dive procedures, while surface cruising on diesels,  having gunnery people at the bowgun, surfacing, charging batteries, exhaustblowing of tanks to mention some, they all had to be exercised.
You reading about people preparing the bridge after the diving command could be a misunderstanding. The CO. shut the top hatch soonest possible after the dive command. A possible situation could be the early war situation while carry out sinking by gunnery and a sudden air attack. I don`t know the procedure for that situation, we never had a casing gun.
Hopefully this might give you an impression and a possible time estimation of the diving time bearing in mind that a use of Q and increase of speed would improve the matter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Jul , 2014, 14:14
Hi Gentlemen,

The Type VII manual shows the distance to the center of mass for all of the tanks. But the center of mass is not static, it can move - what position (horizontally) should I use for placing the tanks based on the information of the manual? (I've tried to estimate geometrical position of the center of mass (of the tanks itself) for each tank before, but this is extremely intuitive and just a rough guess)

Mark, when I was working on Der Leitende Ingenieur project, I developed the algorithm to calculate the geometrical center of the tank (of any shape, described as set of polygons). I could assume any level of water in this tank and calculate the center of mass. Then I planed to create a 3d model of the U-Boat, which would consist of all tanks, whose shape, volume and localization would be restored as closely to the real as possible. Then I would be able to calculate moments of force for each tank (for any water level in the tank) and then for the whole boat.


Do you have a detailed picture of a kingston? Or of the venting valves? I want to know how open these things really are when opened. (if I can use the whole area in the calculation).

Try to look for the U99 photos in the dry dock.

Also the "diving procedure" does not mention MBT1 at all, what about MBT1 when was it flooded?

The MBT1 is mentioned in the paragraph 9 of the diving procedure.

You will find more details here: http://uboatarchive.net/DivingRegulations.htm
(section VII and XII)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jul , 2014, 07:16
Thanks Tore & Maciek, I finally found time to read the http://uboatarchive.net/DivingRegulations.htm (http://uboatarchive.net/DivingRegulations.htm) (slowly) again yesterday. The other page on uboatarchive is misleading, Jerry should take a look on that.


Simulating the real shape of the tanks would require too much calculations per second which is bad for the overall performance and will heat up the devices and drain the battery. I could add this to the later desktop versions. But I think it might be pretty hard to find the correct shape from the available drawings.





I don't understood how the regulating tanks and cells are operated since I've read that:


Quote
As soon as it is possible, [i.e. when the regulating and reserve fuel oil tanks have been converted for use as regulating tanks] two regulating tanks are to be cross connected ready to flood and two regulating tanks ready to pump, namely one about half-full under 3 to 4 at as a shallow pumping regulating tank, the other approximately 2/3 full under 10 to 12 at as a deep pumping regulating tank.  Boats with only two regulating tanks operate one as a flooding regulating tank, the other as a deep pumping regulating tank.



When they are filled differently (only 2 in use) they would create a torque. This makes no sense for me.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Jul , 2014, 08:07
Hi,

Simulating the real shape of the tanks would require too much calculations per second which is bad for the overall performance and will heat up the devices and drain the battery. I could add this to the later desktop versions. But I think it might be pretty hard to find the correct shape from the available drawings.

Well, you are right - the overall performance is important factor when developing on mobile devices.
I'm optimistic about modeling the shape of the tanks from the drawings - with help of the guys from this forum it should be doable :)

I don't understood how the regulating tanks and cells are operated since I've read that:


Quote
As soon as it is possible, [i.e. when the regulating and reserve fuel oil tanks have been converted for use as regulating tanks] two regulating tanks are to be cross connected ready to flood and two regulating tanks ready to pump, namely one about half-full under 3 to 4 at as a shallow pumping regulating tank, the other approximately 2/3 full under 10 to 12 at as a deep pumping regulating tank.  Boats with only two regulating tanks operate one as a flooding regulating tank, the other as a deep pumping regulating tank.



When they are filled differently (only 2 in use) they would create a torque. This makes no sense for me.

The regulating tanks are located near the boat center of gravity not without the reason - the moment of force is small due to short arm (0,1 m for regulating tank 2 and 3 meters for regulating tank 1) and small weight (up to 8 tons for regulating tank 2 and 5 tons for regulating tank 1) - consider the torpedo tube - distance from center of mass ~25 meters and weight ~1,5 ton.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jul , 2014, 08:16
I thought more of the problem on the roll-axis when only 2 reglers can be used.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jul , 2014, 10:32
Hello Mr. Tore,


I really like your Presentation Plaque and the model of the Kaura (ex - U995).  That is a unique lifetime achievement.  I ran the name KAURA through several web based translators and all I get is KAURA = KAURA.  Is KAURA a woman's name. like the passenger liner Queen Elizabeth II?


For about 6 months, I have been working on a book for my own personal use on the Type VIIC U-Boat based on the Skizzenbuck plates from Captain Jerry Mason's web site (uboatarchive.net), and addition expert information and advice from Maciek and Mr. Tore.


I'm about 3/4 done with about 272 pages (mostly drawings and explanation of systems).  At this point, I am having problems with the on-board Port Welding circuits in relation to the general Rotary Switchboard circuits presented in a Preliminary training manual.  The circuits and components don't match up in the drawings. 


Do you know of any source for the Blade or Rotary Switchboard schematic?  If I had access to either one, then I would have an excellent chance of understanding the electrical circuits of the other?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jul , 2014, 11:55

I'm confused:The watertight stern & bow are located pretty high, it looks like they are just slightly touching the surface with their bottoms under normal conditions so they should take water only in rough seas but the vents are shut then. The only difference it makes in good weather to keep them open is that they are always ready for diving.
Now I think I use the wrong draught. Could someone please make a drawing of the height of the waterline (at different trim conditions)?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2014, 12:46
Don.
The name Kaura is a lighthouse on the rugged long coast of Norway. Our 3 VIICs were called the K class after the WW2 and named:KNM  Kaura, KNM Kya and KNM Kinn all named after lighthouses at the Norwegian coast.
You electric question, about a year ago I found amongst a bunch of old paper a complete electric scheme from I guess KNM Kaura or Kya. these schemes I posted on this thread as from page 100 and 101. Have a look back and see if they are of any use.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2014, 13:04
Mark.
The watertight bow and stern are indeed above the waterline and are not a part of the submerged system, they are used to reduce the pitching in rough surface weather by improving the buoyancy when the stern and bow "take a dip" in into the waves thereby improving the life for the poor buggars at the bridge. We normally kept the vents shut at the surface and it was a routine to check same open at divingpreparations. I cannot remember the draughts at various trims, there are draught marks on the hull, may be Maciek can help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jul , 2014, 18:29
Hello Mr. Tore,


This looks to be a general wiring schematic of U-101 a Type VIIB U-Boat.  I have never seen a general wiring schematic for a U-Boat, and most likely never again (very unique)!  This will not fill in all the blanks, but it does provide a good base to piece each system into place when ever I can find them.  The schematic list U-101 and Blohm & Voss, but U-101 was built by Fried. Krupp - Germaniawerft, Kiel...  Interesting?


Do you have any idea as to the cost to copy your schematic?  If it were not overly expensive, then I would be willing to reimburse you for your cost, time, and mailing expenses for a copy.  They usually put blue prints in a mailing tube for shipment...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jul , 2014, 18:42

Do you have any idea as to the cost to copy your schematic?  If it were not overly expensive, then I would be willing to reimburse you for your cost, time, and mailing expenses for a copy.  They usually put blue prints in a mailing tube for shipment...


I would say a good high resolution scan in a copy shop would be the best solution for this - I guess that's cheaper than mailing and you could share it with dropbox or other free cloud providers.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 00:31
Don.
The drawing is pretty shot and is about 5 feet long in a roll, but I shall consult one of my grandsons who are more conversant in the present days possibilities of restoring. I believe Mark`s suggestion could be an alternative. I don`t believe it is a VIIB schematic, if you look at the title of the drawing it is stamped U 101 and a black square covering the last figure. Blohm & Voss had a contract for building a series of VIIC/41 which were listed as 1010 up to 1019 of which U 1013 up to U 1015 and U 1017-U 1018 were suspended U 1011 and U 1012 were damaged at the yard beyond repair by an airraid July 1943, U 1016 was scuttled somewhere in the Baltic I believe, but U 1019 surrendered in Trondheim Norway may 9Th.1945. I am inclined to believe the drawings were "borrowed" by the Norwegian prior to handing over U 1019 for the deadligth operation.
As I obviously has taken the drawings home for studying, some of my scribblings are on it,  while being EO on the Kaura ex U 995 I would assume they are from the B&V VIIC/41 series used at that time by me for our only VIIC/41 KNM Kaura.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jul , 2014, 11:10
Hello Mr. Tore,


I figured it was a fairly large schematic....  In 1966, I went to the NCR Company Technical Training Center in Dayton, Ohio, to get trained on the Class 450 proof machine.  The 450 was a 20 total mechanical Accounting machine with an OCR printer for encoding the amount on the bottom of a check  It also had a 20 pocket check sorter and a 20 receipt printer module unit.  This was a electro-mechanical monster that failed many of the older mechanical service engineers.  I was previously trained on the Class 390 computer system in 1963, so this was a piece of cake for me.  It had cam switches timed to enabled wired relay logic to enable other cam switches to energize solenoids to engage mechanical functions.  The schematic was 5 x 10 feet and I remember taping it to the wall at night to study the circuits.  The next day we had to demonstrate the schematic circuits section to the instructor's satisfaction!


In January 1963, I was an apprentice new hire with 9 months field experience.  When I was trained on the computer system, every Friday morning there was a "You Bet Your Job Test."  If you scored less than 90%, then you were fired that afternoon!  Our class size was 22 students and 12 months later when I completed the class our number was 11 souls.  Those were the good old days...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Jul , 2014, 11:10
Tore, from the manual:


Quote
For blowing regulating tanks, regulating and reserve fuel oil tanks, and negative buoyancy tanks a blowing manifold is provided in the control room.  The safety valves for regulating tanks and regulating and reserve fuel oil tanks are set at 13 at and for negative buoyancy tanks at 10 at.  Each regulating tank has a pressure differential gauge installed.


That means you can't blow the regulating tanks & cells at depths deeper than 130m right? Only pumping should work then.
Which pressure differential are the gauges showing?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 12:23
Mark.
Not everything is mentioned in manuals, when you are in trouble  the system is open for alternatives, if f.i. you have a lot of water in the bilges I would pump this in a non pressurized regulating tank using the mainbilge pump in parallel, filling the regulating tank. Then pressurize the regulatingtank at fi. 12 ata, put the main bilge pump in series for suctions from the regulating tank, having a suctionpressure say 110 mwc, boost that up with the pump if needed to say another 105 mwc having a capacity of 500 l/min (diff pressure  105 mwc) against total 215 mwc. overboard, hoping the pump, pipe, valve and valve stuffingbox can take it. Same goes of course if you like to pump out water already in the regulating tank. May be a VIIC/41 can survive such depth, possibly not a VIIC, anyhow this is just to give you some fantasies which may be could be built into a game ( and real life) giving the innovative players a chance to survive. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Jul , 2014, 12:50
Ah… nice! You assist the pump with pressure from the tank. Where exactly is the exit to outboard for the pump located?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 13:09
Mark.
I was carried away a bit :D, I guess the official rules are: the static pressure (difference between inlet and outlet) of the main bilge pump  should not exceed 8 atu appr. 80mwc. you could pressurize the regulatingtanks up to 14 ata (app.130mwc.) you can exceed that if you pressurize the adjacent tanks ( Q ,reg-and f.o.bunkertks1) somewhat to reduce the bulkheadstresses, say 3-4 ata.That should give you a better pumpcapacity at 210 m.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 13:25
Mark.
The connections to the sea are shown on the sketch below. Note it is an outlet to Mbt 3. as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Jul , 2014, 13:39
So you could pump to MBT3 instead and try to blow it out with hp air?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 14:01
Mark.
Remember when you are submerged the Kingstons are open and MBT 3 has the ambient sea pressure. So why MBT 3 at all? Well let assume you are pumping the oily bilges and do not want to pump it overboard because you are laying deep hiding and an oilslick is betraying you . You pump it in MBT3 and let it sit there till you blow the MBT3 for surfacing in safer water later. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jul , 2014, 21:03
Hello Mr. Tore,


I have been reviewing back post and I learned that the steam heating system is only used when in port.  That fact makes me feel a lot better because I could not find a heating source on the steam heating Plate...  However, that brings some questions to mind.


1.  When the U-Boat is running on the surface in the North Atlantic at winter time, Is the heat source the diesel engines and using the ventilation system to distribute the heat?


2.  When the U-Boat is running off the coast of Spain, or even worse yet in the Mediterranean, at late summer, doesn't it get kind a HOT!  What do you do to get cool?  I believe the water if pretty warm as well; will diving help at all?


#.  If the U-Boat is sitting on the bottom, say at 150 meters Off the coast of Norway, Isn't it really cold down there?  You can't just throw another log on the fire...?  What do you do to keep warm?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2014, 23:52
Don.
The diesel engines did not take part in the compartment heating and most of the heat dissipation went overboard, in fact sometimes it could be a bit chilly at the maneuveringstand as a huge amount of cold air was drawn in via the dieselair duct. The heating was primarily electric. I cannot remember it was excessively hot in the summertime, this was the time before airconditioning was common and allthough I remember on board surfaceships it could be hot in the Mediterranean most of the submarine was submerged all the time and the sea temperature was some 20-22 degrees C. However people 46 men, electric motors, galley, battery charging etc gives heat dissipation and the only way we could get rid of that was by running the ventilation system taking air from outside, if the air was warm it would not help a lot. 
The sea temperatures along the Norwegian coast varies a lot and particularly in the deep fjords. Offshore the Golfstream keep an average almost constant temperature and the water never excessively cold, in the fjords it varies with the seasons. Particularly in the spring when you have melting of snow and ice creating layers of coldwater with less salinity and making it difficult to keep and good trim. However the layers gave an excellent active sonar protection as the layer were acting like a reflection mirror. Today the have transmitters at different levels screening the layers horizontally. I had most of my service on board patrolling in the Barents sea but I cannot remember it was very cold.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jul , 2014, 00:15
Don,
as Tore said, the heating was primarily electric. The steam heating installation was fitted (I believe) in the early-war U-Boats and abandoned in the end of war. U995 was not equipped with such system.
The steam heaters are visible on these two photos from U570 (below the hatch):
(http://uboatarchive.net/U-570Photo23.jpg)
(http://uboatarchive.net/U-570Photo17.jpg)
The electric heaters were portable devices, which were plugged to the U-Boat electric net.
One of them you can see on this photo from U570 torpedo room:
(http://uboatarchive.net/U-570Photo10.jpg)
I have attached also two more photos of electric and steam heaters.
As far as I know, type IX U-Boats had the same heating installations as type VII.
But type XB mine-layers were fitted with steam heating system, which consisted of steam generators, whose utilized the heat from the exhaust gases.
--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Jul , 2014, 00:28
Ah… nice! You assist the pump with pressure from the tank. Where exactly is the exit to outboard for the pump located?
I have attached two photos of the port and starboard side of the boat.
On port there is visible only one hole for inlet/outlet, on the starboard - two.
I have also attached sketch made by Tore, where I marked with blue line one more opening (water inlet).
I suppose, that the "blue one" is the inlet on the starboard side, while the other inlet and outlet - on the port side.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2014, 00:42
Maciek.
Right you are Maciek, I forgot that one.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 09 Jul , 2014, 06:31
great, thanks Tore and Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 09 Jul , 2014, 09:23
Tore, at Trim A (no oil in MBTs)…


how much water was usually the trim cells when surfaced and when submerging?
Currently in my simulation it looks like there should be at least water in the aft trim cell to trim the boat when submerged.



…and how much water was in the regulating cells for the torpedoes at the beginning? (if no torpedo was used) does it carry water for the flooding of the tubes? or where the tubes already flooded?




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jul , 2014, 10:03
Thanks Mr, Tore and Maciek...


Hi Maciek,


Since they were using electric space heaters to keep warm in cold weather, does that mean at least one e-motor was running as a generator to keep the batteries topped?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2014, 11:13
Don.
Charging batteries was normally not depending upon the electric consumption, the condition of the batteries was the ruling factor. Twice a day the battery cells were checked for voltage, acid specific weight and temperatures. Normally we started charging when the values dropped below a limit. If however if circumstances were such that  fully charged batteries would be required, this was overruling the ideal charging.
A constant top charging would increase the risk for "gassing" eg. producing explosive hydrogengasses as well as batteries becoming "tardy". In order to keep the batteries in top shape we "drained" the batteries to the bottom once a month by running the E-motors alongside and starting charging immediately when the batteries were drained.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2014, 12:06
Mark.
Trimming tanks.
I don`t remember we had any specific rules how much and sorry I can`t remember the forward and aft draugth. The procedure was to take a rough calculation then  balancing dive to check the calculation and sometimes it could be wrong. Then by the regulating tanks ( we never used same as f.oil bunkertanks) find an optimal trim and by adjusting the trimtanks say half full or less. The exact amount of regulatingwater would vary almost all the time depending upon consumptions as fuel, provision, freshwater etc. As the moment arm for the pitch was very long you needed only to move small amount of water to compensate for the trim f.i, as I have mentioned before, when diving station was ordered the movement of people from the 3 watch system to divingstation would require 400 liters to be pumped (yes we pumped) from aft to forward.
I leave your torpedo questions to Maciek he is more conversant with this topic than me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jul , 2014, 21:47
Hello Mr. Tore,


I have a question about a blower vent...  I have drawn a rendition of the vent that might work.  However, the way they have drawn it on Plate 19, it looks like one blower will feed the other one and very little air would go out the vents???


Am I all wrong headed again?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2014, 01:55
Don.
I believe you have misunderstood the selectorsymbol. As you know on the VIICs , not equipped with schnorchel, you have two ventilation airducts one for intake the other exhaust, both operated from the controlroom and having airducts outside the pressurehull to the engineroom where they enter the pressurehull via a hullvalve with drain. I have made a sketch below showing the system green is intake and yellow exhaust. The ventilation situation you are referring to is both ventilatorfans operating in parallel which mean they have common inlet suction ( green) and exhaust (yellow). The fan selectorvalve select the suction from a number of alternatives and consist of two valves a circular selector slidevalve and a hull inletvalve.Likewise the exhaust selector slidevalve has a number of alternative positions as well as a hull exhaustvalve in one unit. If you study the sketches and photo I guess you shall have a better understanding. Remember there are many other valves in the ventilatingsystem which should be operated to get the alternative required not just the slide selectorvalve.
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2014, 03:48
Hi Gentlemen,

…and how much water was in the regulating cells for the torpedoes at the beginning? (if no torpedo was used) does it carry water for the flooding of the tubes? or where the tubes already flooded?

Well, from my studies of this topic (as no descriptions or manuals are available) I think, that torpedo compensating tanks (Torpedozelle) initially contained amount of water sufficient to flood tubes with torpedoes within them (that is about 370 litres per tube, that means that Torpedozelle 1 - aft - contained 370 litres of total 2350 litres volume and Torpedozelle 2 and 3 contained 740 litres of total 5750 litres each).
I think, that tubes were flooded from compensating tanks because in such case, the weight of boat did not change, and the trim changed only slightly.
When the torpedo was launched, the tube was fully flooded with overboard water (through the muzzle door). After closing the muzzle door, the tube was drained to the torpedo compensating tank (1680 litres of water).

Torpedozellen were also used as the aid to trim the boat, when some of the torpedoes were disposed.

And small interesting fact - aft torpedo compensating tank and one of forward compensating tanks could be used as storage tanks for wash water - they were fitted with piping to the wash water installation.
In middle period of war, forward tank was also used as fuel oil storage tank - to extend the operational range of the boat.
The U458 KTB says, that when the boat stayed in Saint Nazaire between first and second patrol (that means between 27 August - 1 October 1942), one forward torpedo compensating tank was modified to storage fuel. The additional 5,75 m3 of fuel extended patrol by two days (at 10 knots, both diesels 275 RPM).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2014, 05:19
Mark
Re Maciek post on torpedoinstallation.
It is astonishing to see how the germans used all opportunities to extend the patrols only by a few days. I made a calculation on having both fuel oil bunker and regulating tanks 1  filled with fuel, both tanks together would extend the running of the two diesels at max continuous load by some 20 hours. Otherwise thanks to Maciek I learned something new about the alternative use of the torpedo installation. I have mentioned previously our contribution to alternative use, ejecting garbage through the torpedo tubes on very long submerged schnorchling patrols. This happened to much dismay from the torpedopeople. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 10 Jul , 2014, 07:19
Thanks again… btw Tore it would be interesting to see an example how you calculated things aboard. I guess you had rules of thumb to speed things up?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2014, 08:22
Mark.
Contrary to the Germans, our EO. task was not involving trim calculations, that was No.1`s job, so I don`t remember exactly. We used as you say rule of the thumb in addition to tables and graphs I would believe, not much calculation. A testdive was the most important thing, that would reveal any mistakes and could be corrected by experience. But in order to prevent too much excitement you should be somewhat close to the correct figures. I must confess however we sometimes had excitement. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 10 Jul , 2014, 16:55
Thanks Tore, I still have some question about the flooding & drainage installation:
- The water inlet, I guess it worked with the natural water pressure and you don't need the pump at all to flood the regulating tanks right?
- Is the diameter of the (water) pipes of the flooding & drainage installation identical to the ones used to blow out the tanks with compressed air?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jul , 2014, 17:37
Hello Mr. Tore,


On Plate 18 - There are 3 Air Conditioning Units on the intake / suction lines...  Were those just evaporation units? They simply ran water across a filter and interior air was then drawn through the filter.  The water evaporation and chilled the air and it was then distributed throughout the U-Boat....  Although, that would increase the humidity, so I'm not sure about the evap unit???


I seen the evap units used in many locations in the High Desert State of Arizona where my brother lives.  It is very dry and arid, so evap units work.  However, if the humidity gets above 35 percent, then evap units don't work so well...

A/C back in the 40's and 50's were quite large and required Freon gas....


Also, My DVD/CD of U-995 does not seem to have good photos of the hand-wheel with the Slide Selector lever above it.  Do you have some good photos?  There are 2 units, one for the Port blower and one for the Starboard blower correct?


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2014, 22:15
Don,

On Plate 18 - There are 3 Air Conditioning Units on the intake / suction lines...  Were those just evaporation units? They simply ran water across a filter and interior air was then drawn through the filter.  The water evaporation and chilled the air and it was then distributed throughout the U-Boat....  Although, that would increase the humidity, so I'm not sure about the evap unit???

The translation is quite misleading - these three units are the carbon dioxide absorbents. The units in the control room and forward torpedo room are visible on these photos:
(http://u-historia.com/uhistoria/tecnico/visitaguiada/ventilaciones/renovacioncentral.jpg)

(http://www.ubootwaffe.pl/images/phocagallery/okrety/u995/U-995_095.jpg)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jul , 2014, 22:52
Thanks Maciek,


A/C didn't sound right, but it was spelled out on Plate 18: Air Conditioning Unit... So, these would come into use when the U-Boat is submerged and they are re-circulating the air inside the pressure hull???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jul , 2014, 23:12
That's right, Don.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2014, 00:25
Thanks Tore, I still have some question about the flooding & drainage installation:
- The water inlet, I guess it worked with the natural water pressure and you don't need the pump at all to flood the regulating tanks right?
- Is the diameter of the (water) pipes of the flooding & drainage installation identical to the ones used to blow out the tanks with compressed air?




Mark.
Surfaced, the filling of the regulatingtanks could be done by natural seawater pressure only up to the draugthline of the submarine, submerged of course all the way. I Guess the fine floodline to the distribution chest has a smaller diameter than the other pipes and as you use the latter lines for moving the water being pumped or blown I migth have misunderstood the last part of your question.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2014, 01:38
Thanks Maciek,


A/C didn't sound right, but it was spelled out on Plate 18: Air Conditioning Unit... So, these would come into use when the U-Boat is submerged and they are recirculating the air inside the pressure hull???


Regards,
Don_
Don.
In addition to Macieks answer. The CO2 absorbent canisters fitted in ventilation system were a kind of old fashioned scrubbers filled with soda lime granules as reactors. They produced heat and had a non reversible chemical reaction thus a limited lifetime and was only used at a prolonged submersible situations. The procedure at long dives without schnorchling was every man not absolutely needed goes to bed using as little air as possible. The after say some 24-30 hours it became uncomfortable as the CO2 became excessively high and you connected the "scrubbers". The excessive CO2 created a heavy panting and when the "scrubbers" worked the situation became better, then after a while you got problem with the  reduced oxygen and had to connect the oxygen flasks to the ventilation system.
Anyhow contrarily to today, the system was in use only very seldom, I believe in my time we used it once or twice a year. We did not use any sophisticated systems for monitoring the air quality, only experience.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2014, 02:37
Don.
Ventilation shaft hullvalve and selector slide.
Below is the best photo I have, showing the ventilation hullvalve and selector slide in one housing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 Jul , 2014, 03:38
We did not use any sophisticated systems for monitoring the air quality, only experience.

When on 7th May 1945 La Rochelle was surrendered to Allies, they captured decommissioned (but still afloat) U776 (type VIIC U-Boat).
The boat was overhauled and commissioned into the French Navy, where was named Laubie. She was in Service till 1961. She had three accidents:
- on 17th July 1950, during the exercises near the Morocco coast, during surfacing she was rammed by frigate La Surprise (ex HMS Torridge)
- on 2nd May 1960, near Alger, she was rammed on periscope depth by passenger liner Ville de Marseille
- on 22 September 1961 she was rammed (also on periscope depth, when schnorcheling) by submarine Espadon

Laubie also took part as a support for submarine La Creole during the Suez Crisis in 1956.
In 1958, her commander was lieutenant Bernard Louzeau, who (9 years later) became commander of first French nuclear sub - Le Redoutable.
Anyway, till 60s, French submariners also did not have any sophisticated systems for monitoring air quality. To deal with this problem, they took aboard small dogs.
Due to their small size and weight, the dogs reacted quickly on the air quality changes. When the dogs became lethargic - the air purification measures were taken.
On the board of Laubie, there was cocker spaniel name Folk. The dog loved retrieving the bottles, which were thrown away overboard by crew.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 11 Jul , 2014, 04:44
I guess Laubie Folk had some influence on how often they were surfacing… 3 times a day :D …poor conning tower
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2014, 05:04
Maciek.
We did not have any dogs, I Guess I would rather copy the miners using a canary bird. However we got the experience of foul air on the body and f.i. allowing one cigarette ( stupid) pr man. If the match did not lit, we were short of oxygen. ;D
We had in fact some cooperation with the French exchanging ideas how to run a VIIC, a couple of our officers were on board one of the french VIICs for a few days I guess this was back in 1951-52.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 11 Jul , 2014, 05:18
I will quote circumstances of the last Laubie accident. On 22 September 1961 she served as the target for newly developed homing torpedoes. She had to schnorkeling, while Espadon had to detect her and attack with torpedoes. Commander of Espadon wanted to take up the position behind Laubie stern. He detected her and estimated her course visually - through periscope, using the relative position of the Laubie snorkel head and periscope. But he forgot, that Laubie Schnorchel was (unlike in case modern subs) in front of periscope. And so he took up position in front of Laubie.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 11 Jul , 2014, 11:08
Tore, when you fill a tank with the flooding & drainage installation where does the air which is already inside the tank move to?


and when you pump water into a tank is there a back pressure valve in the line (between the pump and the tank)?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2014, 11:47
Mark.
Venting of the reg.tanks and Q.
 The Q as well as the regulatingtanks 1 and 2 port and stb have an inboard venting with sight glasses all ending in a muffler down at the controlroom bilge. The pipes and muffler from the regulating tanks 1 and 2 are fitted on the aft side of the attack periscope housing in the controlroom as seen on the sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jul , 2014, 22:41
Hello Mr. Tore,


What is the function of the black and red handles near the Main Pump?


See photo -


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2014, 00:06
Don.
On valves having difficult access you have extensions of the valvespindle to the handle.On your photo the black handle has an extensionrod which ends in the air, I guess it could be meant for the suction valve for the main bilge pump. The red handle is a seawater board handle with extension to a board valve hard to identify right now. I`ll return when I get the answer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 12 Jul , 2014, 05:19
Thanks Tore.


Maciek do you also know the diameters of the different (air and water) lines of the flooding and drainage installation?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jul , 2014, 18:59
Hello All,


It was stated that D2, D3, and D4 was the ballast system...  Could we include the Negative Buoyancy tanks in that category as well?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jul , 2014, 22:08
Hello Mr. Tore,


Did you ever have to use the port e-motor I as a welding convector?  Did you see the e-machinist set things up on the Rotary Switchboard on Kaura (U-995)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jul , 2014, 00:05
Don.
In a way may be, but I would not say Q (neg. buoyancy) tank was regular ballast tank. As you know it was a help to speed up the first stage of diving than anything else.
Tore
Hello All,


It was stated that D2, D3, and D4 was the ballast system...  Could we include the Negative Buoyancy tanks in that category as well?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jul , 2014, 00:12
Hello Mr. Tore,


Did you ever have to use the port e-motor I as a welding convector?  Did you see the e-machinist set things up on the Rotary Switchboard on Kaura (U-995)?


Regards,
Don_
Don.
We did not have welding equipment onboard. I most probably have seen the first electrician working on the switchboard,but cannot remember the reason why.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jul , 2014, 18:10
Hello Mr. Tore,


The Lime Water Plate: 26 indicate valve (a), I assume 4 different valves are used to spray lime water on the batteries.  Is the spray above, below, or where?  Where does the Lime water come from?  Is it a pre-mixes solution that's taken onboard when taking on supplies at port, or is this something that was mixed as needed?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Jul , 2014, 18:55
Hello Mr. Tore,


The Lime Water Plate: 26 indicate valve (a), I assume 4 different valves are used to spray lime water on the batteries.  Is the spray above, below, or where?  Where does the Lime water come from?  Is it a pre-mixes solution that's taken onboard when taking on supplies at port, or is this something that was mixed as needed?


Regards,
Don_

Don, I believe pre-Type VIIC/41 it was above, on the VIIC/41's they change it to below.

I also believe they added lime to a pipe opening in the Control Room and then run water through the lime and pipe.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jul , 2014, 20:58
Thanks Simon...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jul , 2014, 00:09
Don.
In addition to Simons answer, good to see you are still active Simon, I believe the limespray system is very much similar to the corrosionoil system, very seldom used and as such based on a hose connection system which could be hooked up to f.i. the hand coolingwaterpump in the engineroom. I don`t believe the lime was stored in liquid state on board, rather as a powder in canisters, which could be mixed with water. I cannot remember we carried any lime on board neither ever used the limespray. However once it was a narrow escape though. When surfacing in a bad weather a huge wave hit us at-wartship  just when our stability was at it`s worst,( metacentric hight almost 0) and we got a list, I remember looking at the inclinometer, between 35 and 40 degrees and that is a lot. Of course we checked the battery compartments but didn`t find any acidspill.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Jul , 2014, 01:29
Hi Gentlemen,

I believe the limespray system is very much similar to the corrosionoil system, very seldom used and as such based on a hose connection system which could be hooked up to f.i. the hand coolingwaterpump in the engineroom. I don`t believe the lime was stored in liquid state on board, rather as a powder in canisters, which could be mixed with water. I cannot remember we carried any lime on board neither ever used the limespray. However once it was a narrow escape though.

American report on type IXC U-Boat provides some further details:
Quote
Corrosion protection for battery wells from spilled electrolyte is provided by means of the so-called lime-milk system (Kalkmilchanlage).  This is merely a pipe fitted with a funnel or hose connection at the upper end, and with a perforated section or a bilge strainer at the lower end in each battery well.  By pouring milk of lime (slaked lime in water solution) into the upper end, an alkali to neutralize the battery acid is, in older vessels, sprayed onto the wing bulkheads of the battery wells from whence it finds its way to the bottom of the battery well.  On newer vessels the solution is delivered directly to the bottom of the battery wells.     
The solution is normally evacuated by way of the drain system.

Source: http://uboatarchive.net/DesignStudiesTypeIXC.htm

When surfacing in a bad weather a huge wave hit us at-wartship  just when our stability was at it`s worst,( metacentric hight almost 0) and we got a list, I remember looking at the inclinometer, between 35 and 40 degrees and that is a lot. Of course we checked the battery compartments but didn`t find any acidspill.

The cells of the battery could stand the trim changes up to 60 degrees and the heeling up to 45 degrees without acid spill.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jul , 2014, 11:10
Hi Maciek,


They mix a solution of Lime and water... Where is the solution held, and how does it get introduced into a water system that sprays the walls of the battery room with the diluted lime water?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Jul , 2014, 12:07
Hi Don,
They mix a solution of Lime and water... Where is the solution held, and how does it get introduced into a water system that sprays the walls of the battery room with the diluted lime water?
I don't know nothing more than quoted above. I suppose (as Tore said), that they held kali powder in canisters or cans, and mixed with water in buckets when needed. Then, the solution was poured into the funnel in the upper part of the piping. Solution flowing through the piping, was distributed over the battery compartment through the holes in the pipe (maybe the spray is too strong word). I suppose, that the piping was led around the compartment along the walls, and the solution "sprayed" the walls.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jul , 2014, 13:09
Don.
In the unlikely event of acid spill, (having a pitch exceeding 60 degrees and list exceeding 45 degrees) most of the acid ends in the battery compartment bilges and you want to neutralize that prior to pumping the bilges by the bilgepump. As Maciek says I believe the lime granulate or powder can be solved in water in any container or bucket prior to be pumped by the handpump. The lime distributionpipe close to the batterycompartments bilges has a hoseconnection where you can connect a hose to the handpump discharge hoseconnection. You can see both connections on the piping plan.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Jul , 2014, 09:08
Tore, does it really take several minutes to fill the regulating tanks completely with water?


Are there any tanks that could not be blown with the diesels? (except those that could be pumped only)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2014, 11:04
Mark.
I guess the filling time shall vary depending on how you fill them, by natural flooding the filling pressure surfaced varies between appr. 2 mWC. and 0, capacity of one reg. tank 7,6 m3. piping appr. 100 mm., if you fill with the main bilge and ballastpump you might have a filling capacity of 1,3m3/min against 15 m WC however restricted to a pipe diam of appr 100mm., the reserve fuel and reg. tanks 1 have a capacity each of 4.7 m3 and have of course a shorter filling time. Otherwise, submerged the filling pressure by natural flooding varies  with the depth. I never logged the time , but I guess with the above input you are able to estimate the time, remember the inboard venting pipe which might influence the head due to resistance in pipe and muffler.
Only the main ballasttanks 1, 2 and 4 port and stb.,3 and 5 are possible to blow by exhaust.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2014, 11:51
Hello Mr. Tore,


I have a few questions about Plate 21 Water...


Q1.  On the Skizzenbuch they list Hot Sea water --- I don't see a heating element to heat the water?
Q2.  Cold sea water is just plain sea water and not chilled?
Q3.  Below Waste Tank 1 they show a pipe connecting to the Washing Water Line...  Is this really true?  They crossed waste water with washing water???  I sure hope not!  Perhaps that line should have gone to the drain of that sink...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2014, 11:52
Post a photo....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Jul , 2014, 12:00
Thanks. Would you ever use the pump to fill the tanks when submerged?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Jul , 2014, 12:08
Q1.  On the Skizzenbuch they list Hot Sea water --- I don't see a heating element to heat the water?


maybe this?
Quote
Sea water installation.
To provide sea water collection in the galley, there is a branch off the cooling water manifold in the diesel engine room, which leads to the valve and a tap in the wash sink.
The warm sea water installation branches off from cooling water head tank in the conning tower casing and leads to the washbasins in both W.C.s and to the wash sink in the galley.
The discharge line of the auxiliary drain and trim pump branches off to the deck wash line.  A shower head can be connected to this line, attached to the net protector, and stowed again after usage.


and maybe the distilling unit produced hot sea water?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2014, 12:17
I thought about that, but doesn't the engine cooling water contain an anti-corrosion chemical for the diesel engine?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Jul , 2014, 12:24
No idea, but that sounds logical  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2014, 14:29
Don.
The hot seawater pipe is a pipe connected to the headertank for the compensating watertank up in the tower casing. The headertank is topped up by a pipe from the hot engine coolingwater at the exhaustsilencer. The engine coolingwater is not a closed circuit and has no additives. Cold seawater is just natural seawater without any cooling. The wastewater tank 1 has only two pipe connections, the drain from the galleysink and the bilgewater suctionpipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2014, 14:41
Don.
Further to my post above, on U 995 it is a horizontal electric pump taking its suction from the coolingwater of the exhaustmanifold alongside the engine and I presume discharge warm cooling water to the galley, I cannot remember this arrangement, but you can see same on photos of the forwad port side of the engine room and described by me previously on this thread. I have not seen any sketch showing this system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2014, 14:46
Mark.
I believe you fill the regulating tanks by natural flooding while submerged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2014, 22:15
Hello Mr. Tore,


Thank you - I did find information on the hot water system and the anti-corrosion system.  Those systems are cross contaminated because the hot water passes through the same components as the anti-corrosion oil.  Not at the same time, but a residue will remain...


Questions
Q1.  Did the distilled drinking water have a smell or bad taste?
Q2.  I suppose the shower was with salt water and a special soap; did it work?
Q3.  The e-motors and bearings were cooled by sea water; did it have to be shutdown at a great depth because         of external pressure?
Q4.  How much anti-corrosion oil was brought on board for a 56 day mission?  55 Gallon drum?
Q5.  Was there a means to wash your clothes? or, just burn them after a mission?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2014, 23:53
Don.
The anti corrosion oil was never used when I was on board,(almost 3 years) and I guess it was not used permanently, more like an "impregnation" of the steel/ castiron. We did not analyze the coolingwater but it it was no sign or smell of any contamination. In my part of the world direct seawatercooling was commonly used on diesels and semidiesels particularly in the  fishingvessels without any anti corrosionprotection.
I guess the distilled water was primarily used for refill of the batteries, we never used same for drinkingwater.
During the WW2 real soap was rationed and hard to get and I remember the soap was not that great even in freshwater, so I guess the Germans used the shower just to have a rinse and cooling off,  we did not used the shower, but during long missions we did most of the washing in seawater and you could have a special soap for that.
Although we had standard procedure to shut off as much as possible of the cooling watersystems going deep, I believe for the e-motors and thrustbearings the cooling circuit was open at depths down to 100 m.
We did not have any anticorrosion barrels on board.
We did not have any laundry facilities on board, however except for long missions, a submarinetender was usually in the neighbourhood which had the facilities, otherwise some of the worst clothings had to be dumped as you say.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Jul , 2014, 18:46
Hello Mr. Tore,


One of the British reports states there is a master blowing valve in the engine room for blowing the ballast tanks with diesel exhaust one at a time.  They state that the two muffler valves are shut to blow the ballast...


I see it this way...


The blowing is carried out by opening at least one of the Muffler Valves (f) in the engine room and closing its accompanying Exhaust Gas Outboard Flap Valve (e) to re-direct gases to the blowing manifold.  One ballast tank is blown at a time.  The engine in use for blowing may be running light or propelling and is run at a speed of no less than 300 RPM.  It is important that the Exhaust Gas Outboard Flap valve should not be open at this time.  If it is, the tanks will vent at a slower rate because you will loose substantial exhaust gas pressure through the muffler.  The second diesel would be re-charging the batteries after a dive...


Would you ever blow the ballast tanks with both diesel engines?  It looks like you could according to the drawing...


I do not see a master valve between the blowing manifold and the muffler valves...  Am I missing something?  What would be the proper blowing tank sequence?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jul , 2014, 01:02
Don.
When you start exhaustgas blowing, one of the diesel is started the normal way having the inner and outer (muffler) main exhaustgas valves open, when the engine is running smoothly you adjust the exhaust pressure by throttling the main exhaust mufflervalve, the inner main exhaustvalve is fully open, as you open the mainblowing valve admitting the exhaustgases to the distribution panel in the controlroom. I don`t think as a rule one  MBT is blown at the time. The ruling factor is the trim of the submarine as an excessive faulty trim would lead the exhaustgases to the MBT having the lowest resistance and upset the the trim even more, hence you adjust the distribution of the blowing in the controlroom. We used only one diesel for blowing, remember, this was usually a fairly slow process (10- 15 min) at a semisurfaced position using only 5 m WC pressure and one diesel emitted ample exhaustvolume for blowing the tanks. The US and RN submarines used electric blowers for this last stage blowing, which primarily is used for saving HP air.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Jul , 2014, 00:34
Don
Reading my yesterdays post I realize you might get the impression that the diesel exhaust blowing pipes enters the controlroom, for the sake of order it is only the distributionvalve spindles and handwheels which are in the controlroom the distribution valvechest and pipes are outside the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Jul , 2014, 14:56
Hello Mr. Tore,


Thank you for the update...  The only thing that surprised me was the Outboard Exhaust Valve was not fully closed when blowing the ballast.  I guess once you establish the correct exhaust pressure by adjusting the valve, then excessive back pressure would affect the engine performance...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jul , 2014, 00:17
Don.
Shutting the exhaustsilencer flapvalve would have led to excessive exhaustpressure almost immediately. The dieselengine acts like a piston pump having a piston displacement of 0,057 m3 for every 2.nd revs ( 4 stroke). With 6 pistons and say 300 revs/min this would be about 50 m3/min exhaust. Compressing this to 1,5 ata (max allowable blowingpressure) would give appr. 34 m3/min exhaustgas at 1,5 ata, which is far to much for blowing the MBTs. Thus the silencer flapvalve had to be partly open and as the pressure varied was constantly adjusted by the engineer maintaining the correct pressure. The exhaustblowing of MBTs required ( in the controlroom) a constant monitoring of the pressure to each tank as the resistance of the tanks varied according to the depth of the Kingstons and floodgates ( 1 and 5). I have tried to put up a sketch showing the variation at 2 degrees bow up surfacing. For the saddletanks in ballast configuration, the saddletanks Kingstons are substantially higher up than MBT 3 and having the least exhaust blowing resistance of all MBTs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Jul , 2014, 04:39
Hi Tore,

The dieselengine acts like a piston pump having a piston displacement of 0,057 m3 for every 2.nd revs ( 4 stroke). With 6 pistons and say 300 revs/min this would be about 50 m3/min exhaust. Compressing this to 1,5 ata (max allowable blowingpressure) would give appr. 34 m3/min exhaustgas at 1,5 ata, which is far to much for blowing the MBTs.

Do you think, is it doable, to blow ballast tanks using diesel engine as compressor, which is driven by electric motors?
I mean the situation, when there no compressed air left in the air flasks to blow or start diesel (other option - to start diesel engines by electric motors).

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jul , 2014, 05:41
Maciek!
Interesting twist. To my opinion using the E-motor as at starting motor would probably work. In that case I would start turning with the indicatorcocks open, then shutting same when revs are adequate for switching to fuel and you would probably get ignition. Using a 400 mm cyl.diameter 4stroke engine as an electric driven compressor would probably work surfaced,  the air pressure would be limited but probably sufficient for LP blowing the ballasttanks. If out of HP air I would rather start the engine by the E-motors and blow the MBTs by exhaust. By the way I vaguely seem to remember we once started the engine by the E-motor as a test.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jul , 2014, 11:02
Tore, I guess this is hard to tell but how fast did the depth gauges respond to changes of depth? I want to let this change look real on my gauges. Was  the 25m depth gauge needle more "dancing" in really heavy seas or was is sluggish with just a little movement of the needle?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jul , 2014, 12:06
Mark.
The depth gauge 0-25 m is an ordinary direct manometer and as such has an immediate respondtime. I cannot remember any large fluctuation due to surface waves, however at heavy swell the submarine moved up and down and the depthgauge showed  the variation of depth immediately. Under such conditions keeping the periscope depth was very challenging. You could feel the swell down to more than 50 meter during a severe storm. By the way on U 995 it looks as if somebody has pinched the greater depth gauge having coloured sections on the dial.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jul , 2014, 14:53
Thanks Tore, another thing… I've "connected" the compass to my (new upgraded) boat today and this is how the sea affects the heading of the boat at full speed - do you think that is within normal range?


http://hessburg.com/Screenshots/Heading.mov
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jul , 2014, 15:32
Tore, what exactly do they mean by "Beide Maschinen 10 weniger"? 10 what? 10 RPM? And when they set it to "Achtung" what does that mean for the people in the engine room?


(http://hessburg.com/Screenshots/10weniger.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jul , 2014, 23:17
Mark.
I tried several times times to connect your link, but somehow I can`t get connected. "Beide maschinen 10 weniger " would mean 10 rpm lower I guess we never used that. Achtung would be the same as "stand by" on any engineroom telegraph meaning the engine crew should be ready for action, being mostly for starting up or maneuvering. On a submarine it could be ready for surfacing, diving, schnorchling, batterycharging  etc. as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jul , 2014, 00:27
Tore, I've uploaded it to youtube: http://www.youtube.com/watch?v=RKR3UCv_l9I&feature=youtu.be


(rudder is set to 0°)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jul , 2014, 01:52
Mark.
Amazing. I assume it is the gyro repeater and as such I believe OK.( I am not a navigator). The general impression is as you have said previously, a simplification on the bridge to the essentials for the game. However the behaviour of the U boat in heavy sea seems a bit smooth and fast, like a hot knife through butter. The lucky buggars on the bridge in your sub. seems to be very dry, unfortunately there was a lot of spray and some times even a wave filled the bridge under the weathercondition similar to what you are showing. Usually the people on the bridge wore oilskin dress and a southwest hat during these conditions, even then they got pretty wet. :(
 I see you have introduced a RN flowerclass corvette and an US Fletcherclass destroyer as escort for the convoy, I am not sure if these two vessels operated in a joint escort on the North Atlantic convoys, definitely the flowerclass corvette was in the escort.
But anyhow I am impressed what you are able to make. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2014, 11:46
Hello Mr Tore,


Do you have a photo of the valve wheel for the Outter Exhaust Flap Valve that is adjusted to setup up the pressure for blowing the ballast.  I want to be sure which valve was used for blowing in the engine room...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2014, 12:13
Also a question on the Diesel controls...


The wheel to the right is used for turning on the air pressure to start the engine.  The next lever with a squeeze lever to unlock and the markings are Top "Dis-engage" and the bottom "Start"...  The next lever has the squeeze lever and a button.  If the squeeze level locks the lever in place, then what is the function of the button?


I assume the lever furthest to the left is the fuel control and the marking from top "0" to the bottom "55"...


Would the sequence be:
1.  turn the wheel to supply starting air
2.  move lever to start
3.  When sufficient speed - move the fuel lever to a low amount
4.  Move lever to Dis-engage
5.  Turn off starting air
6.  move fuel lever to get higher RPMs


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jul , 2014, 12:52
Don.
Main (Group) exhaustvalves.
Down below are the 6 port and stb main exhaustvalves we have discussed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jul , 2014, 13:44
Don.
Starting procedure for GW engines.
I am not sure which plan you are referring to, mentioning "disengage" on the starting lever. But basically you are right in your assumption as to the starting procedure. However in addition to this system you have some interlocks and lever for engaging  the supercharger (Roots blower) and shutting the natural aspiration. Further you can see some rudiments from the direct reversible system so it is easy to be confused. I guess the small wheel on the fuel lever is for fine control.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jul , 2014, 14:07
However the behaviour of the U boat in heavy sea seems a bit smooth and fast, like a hot knife through butter.




 I see you have introduced a RN flowerclass corvette and an US Fletcherclass destroyer as escort for the convoy, I am not sure if these two vessels operated in a joint escort on the North Atlantic convoys, definitely the flowerclass corvette was in the escort.
But anyhow I am impressed what you are able to make. ;D
Tore


Thanks


The new buoyancy is still not completely implemented. I'm currently busy with that these days.


I have the PC461 Class as small escorts in range of the american coast. The flower class will sail with british destroyers (currently only have an O class)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2014, 20:18
Hello Mr. Tore,


The one strip beside the lever reads Anlassen (Start) and at the top Detrieb (Uninstall drive or Dis-engage)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jul , 2014, 20:24

The one strip beside the lever reads Anlassen (Start) and at the top Detrieb (Uninstall drive or Dis-engage)?



Don, there is no word "Detrieb" in the german language. Do you mean "Betrieb"? (operation)
http://www.dict.cc/?s=betreiben
http://www.dict.cc/?s=betrieb
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2014, 22:29
Hi Vic,


I seen the error after I reviewed the reversing mechanism...  I could only partially read the 2 items left on the metal plate.


The lever to the right has 4 positions:


Stop       --  top
Operate
Reverse
Starting  --  Bottom


So the starting sequence would be:
1.  Turn the wheel to supply starting air
2.  Move the right lever to starting
3.  When sufficient rpm, move the left lever to a low fuel amount
4.  Move right lever to operate
5.  Turn off starting air
6.  Move left lever to higher rpm


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jul , 2014, 23:05
Don.
Almost correct, but as soon as the cylinders ignite you move the starting air handle back to shut off the air to the cylinders. and then shut the starting air supply valve. The reason is that you  disengage the cylinder startingvalves from the camshaft as soon as possible shutting the valves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jul , 2014, 23:35
Mark.
The way the VIICs behaved in the rough sea fascinated me and the pitching gave a spectacular view. As you know the designers made some effort to reduce  the pitching by introducing the watertight bow and stern as well as on the VIIC/41s, the Atlantic bow, having a flare. The floodgates of the watertight bow and stern contributed even more to the dramatic sight of spray.
I don`t know much about the graphics but as I understand you are busy with the subject right now I have adopted one of my paintings of KNM Kaura ex U 995  (VIIC/41) to show my ideas about the spray. In the game graphic, the spray is almost absent and the sea gushing over the casingdeck drains very quickly. In real life the sea was almost constantly covering the casing deck.
The movie Das Boot gives an excellent impression of the real thing. I am not sure if it is feasible to achieve these effects in a game programme so excuse me for interfering.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jul , 2014, 23:51
The mobile devices can't handle much more spray than shown in this video: https://www.youtube.com/watch?v=5PYCpmEKu5U&list=UU03RMMpKkHkZVROUHFTWYVA


Spray is transparent and everything that is transparent costs a lot of performance because screen pixels has to be drawn several times.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Jul , 2014, 00:25
Mark.
I had the feeling it was something like that ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jul , 2014, 15:09
Hello Mr. Tore,


The lever to the right has 4 positions; Stop, Operate. Reverse. and Starting.  When is the Operate position used?


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 Jul , 2014, 15:23
Tore, do you remember the color of the isolators(?) on this (colored) picture?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jul , 2014, 00:09
Don.
The starting lever has a nameplate which is a rudiment from the direct reversible dieselengine, hence  the 4 positions. First of all, plate 29 has a wrong translation "Umsteuer"does not mean "reverse" it means shifting of the camshaft to ahead or astern position. As the direct reversible engine required a lot of complicated operations as, lifting the cylinder valve rollers up from the camshaft, moving the camshaft axially, lowering the rollers down on the camshaft, starting again etc. they combined parts of these operations in the starting handle by adding links and cams, including various interlocks,  to the startinglever movements. During these timeconsuming prosesses the handle had a position "operate". On the non reversible execution the starting lever had only two functions moving the rollers down ( start) or moving the rollers up ( run) from the camshaft, thereby distributing starting air to the cylinders (start) and shutting of same (run) soon as you achieved the proper revs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jul , 2014, 00:20
Mark.
It is hard to remember such details more than 60 years back. However I thougth they were dark green when I made my model, but it could be dark brown.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jul , 2014, 08:54
Hello Mr. Tore,


On Plate 29, what does the shaft Lenkerwelle do?  The stop and the operate positions have the same valve configuration; that seems redundent?  I think I was wrong on my start sequence; I believe 1st should move lever to start, and then turn on the air.  If I turn on the air first and start moving the lever down to start; I pass reverse (or lifting and reversing) and I would not want that to start???


There is a lot to think about on plate 29...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jul , 2014, 09:15
Now, that photo I had of the engine levers where the starting lever only had two positions; Stop and Starting.  U-995's diesel engine did not have reversing...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 25 Jul , 2014, 13:51

…On Plate 29, what does the shaft Lenkerwelle do?  …


A Lenker is something for steering. Sounds like it has something to do with dive planes or rudders… or maybe the governor?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Jul , 2014, 00:23
Don.
Lenkerwelle is a shaft going along the camshaft. One of the purposes is supporting the  leverarm for the cylinder startingvalve camshaft roller, the other (for direct reversible engines) having  cranks and rods connected to the HP fuelpump camshaft rollers pulling them away from the fuelcams on the camshaft when axially moving same for changing direction of rotation, see plate 30.
I don`t think your last proposal for starting is the correct one. You first open the main starting air supply valve admitting starting air to the cylinder starting valves and startingair manifold. Then you move the startinghandle to start, on a direct reversible engine you pass the "umsteuer" maneuvering position and the run position nothing happens, the run position is only the ventingvalve open the others shut. On the maneuvering position the air is only admitted to the slide for the ahead/asternhandle which remains in the position for rotation  selected by the handle.
When the starting handle is in start position  air is admitted to the top piston on the cylinder startingvalves pushing the rockerarm down and engage the rollers to the starting cams, on direct reversible engines to the cams which are selected by the ahead/ astern handle, and the engine start to run on air. When you obtain the proper revs you move the handle to "betrieb" or "run" the valves supplying air to the "umsteuer" mechanism and top of the cylinder starting valves are shut, the vent valve on the air manifold opens and the spring under the top piston on the cylinder starting valve  is forcing the piston up which lift the starting valve rollers from the camshaft.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Jul , 2014, 00:32
Don.
Yes the U 995 as well as the other of our VIICs did not have direct reversible engines. Thus I was never operating a direct reversible GW engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Jul , 2014, 10:08
Hello Mr. Tore,


Can you please explain this sentence...


"On the maneuvering position the air is only admitted to the slide for the ahead/astern handle which remains in the position for rotation selected by the handle."

Does it mean the handle has to stay in the reverse position in order to start the reverse process?

Regards,
Don_[
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jul , 2014, 00:22
Don.
When you open the main starting supply airvalve, air is supplied to the starting air manifold. If you then put the startinghandle in the "umsteuer"/"reverse" position you open two valves in the airmanifold, 1. air supplyvalve to the  "umsteuer schieber" or slide and 2. the ventingvalve. The air is supplied to the ahead/ astern "reversing" slide, which control the displacement piston for the camshaft. This means the engine is ready for maneuvering. The reversing slide is operated by the ahead/astern handle, removed on non reversible engines but you still see the rudiments. The slide has only two position, ahead or astern and. If at the starting operation the starting lever passes the revers position nothing happens as the air only keeps the reversing mechanism in the ahead/astern handles status quo position.  Thus the starting handle has to be put in "umsteuer" position in order to be able to operate the ahead/astern handle on the direct reversible engine. Below I have tried to sketch (red) the diagram in the "umsteuer" (revers) configuration with the ahead/astern handle placed in ahead position . Further is a picture of the revers handle rudiments on the U-995 engines. Further to the basic movement,  the reversing system consist of a number of interlocks preventing the handles to be moved at the wrong times, which I for simplification have omitted at this stage.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 05 Aug , 2014, 04:31
Hi Tore!  quick noob question. On the inner walls of the upper conning tower of the VIIc. Are those wood slats or steel armor slats? If you answered this already im sorry. ive browsed through this thread but may have missed it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Aug , 2014, 04:58
Hi OldNoob.
For those VIICs operating in the Arctic I guess you had wooden slats which I assume should prevent sticking to the freezing cold steel. The armoured conningtowers were normally armoured plates often included in a shelter armoured box mostly on the starboard side as protection from air machine gunattack. I cannot remember we had any of the kind on our VIIC`s.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 05 Aug , 2014, 08:42
So Teak is wrong.
(https://farm4.staticflickr.com/3866/14649796257_1a8794d70f_c.jpg)
 Where in the world did i get the idea they were wood? LOL
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Aug , 2014, 10:24
OldNoob.
Teak during WW2 in Germany?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 05 Aug , 2014, 17:26
OldNoob.
Teak during WW2 in Germany?
Tore
Indeed. Senility on my part. Thank you for getting me straight.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Aug , 2014, 17:33
Hello Mr. Tore,


Have you ever got your general U-Boat wiring diagram copied?  I believe a great deal could be restored if it were in a digital format?


My main reason for this post....  I have completed my book "Skizzenbuch" for the U-Boat Type VIIC and I would highly regard your personal opinion about the book.  It's 75 percent diagrams and photos with a lot of your words and advice to me about technical matters.  I have been studying the U-Boat since 2003, but I have learned a great deal in the past few months from this web site and you in particular (Thank you!)...


If you could send me [donprince5207@comcast.net] your email address, then I could send you a link to the dropbox that contains the pdf file... 


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Aug , 2014, 22:36
Don.
I am  up at my farm way out in the deep forrest of Norway for the summer and I haven`t seen my grandsons for weeks, however they are coming up this week end and I shall discuss the matter then. As to your skizzenbuch I am looking forward to seeing it and shall send you an Email.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Aug , 2014, 09:20
Tore, do you remember if this symbol thing had a color? I think I've read something somewhere in the manual once about colors of these symbols.





Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Aug , 2014, 11:38

Tore, do you remember if this symbol thing had a color? I think I've read something somewhere in the manual once about colors of these symbols.
Mark, manual says about red marks.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Aug , 2014, 12:48
Thanks - the other one (rounded) has no specified color right?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Aug , 2014, 13:41
Mark.
We had only one VIIC with the old compasscasing (U 995)the others had the new version and by the way  on the present day museum U 995 they have installed the new compasscasing for some reason. We did not use these symbols, thus all the symbols were painted as the rest of the superstructure. On the new compasscasing for the other VIICs I can`t remember it was any symbols. On a black and white photo of the old U 552 it seems that the symbol has the same tint as the compasscasing which obviously is painted black . But as Maciek says manuals is mentioning red.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Aug , 2014, 14:39
It's boring without colors  ;) I'll use red.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Aug , 2014, 16:21
Hi VIC20,


I built a 1/32 model of U-96 and decided the Laughing Sawfish was a green color based on the following article by Dougie Martindale...



http://amp.rokket.biz/docs/laughing_sawfish.pdf


My Brass Tower 1/32nd model....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Aug , 2014, 16:25
FYI....  That fishie is hand painted and not a decal...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Aug , 2014, 16:49
I built a 1/32 model of U-96 and decided the Laughing Sawfish was a green color based on the following article by Dougie Martindale...

http://amp.rokket.biz/docs/laughing_sawfish.pdf (http://amp.rokket.biz/docs/laughing_sawfish.pdf)



Don, I've read the article in january and opted for black :D


The lime green metal sawfish pennant in the article is pretty funny because they think so much about the color that they don't realize those 2 pennants are not identical but they say it is the one of U 96.
Look at the rear fin to body, at the eye, at the mouth and the lenght of the "saw". A completely different thing.



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Aug , 2014, 23:42
Mark.
As you probably know the square with a cross is the marking for the hatch to the emergency ballasttank blowing and the circle with a cross is the external emergency air supply to the ventilationsystem inside the boat. The hatches were made for easy access for divers to the connections inside the casing. Like the system for valve handles and wheels having different shapes for easy identification in bad light, I assume the marking symbols were made raised.
I was a scubadiver for many years and I remember how the colours disappeared even at small depths and the red was first to be eliminated , blue the last, possibly because of the wavelenghts. I was told that nature used less energy to produce red colour hence as a camouflage many fishes were exotic red on the surface only to become black ( which required more energy to make) at modest depth. To make the identification red for divers at depth below say 8-10 meters seems strange to me as you don`t see the red, unless you have a torch of course. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Aug , 2014, 00:20
That's an interesting point. I guess some clerk decided that because of other regulations.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Aug , 2014, 01:25
Don
Q tank, your Skizzenbuch.
I guess your description of the Q tank system might be a bit confusing. Then port and starboard Q have a combined common blowing and venting pipe which is  drawn at both plate 7 and 17. The boardvalve h on plate 7 is the same as boardvalve f at plate 17.  The hullvalves h and f are the hullvalves for blowing as well as venting.The common main blowingvalve is controlled by the red wheel at stb side and the common main ventvalve is on the port side ending in a muffler under the steelcabinet. See my sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Aug , 2014, 21:49
Thank you Mr. Tore,


That is exactly what I need is someone with a close eye for my mistakes and not making a good point.  I have have added a page with your well designed illustration and comments.


As I look at Plate 7 the hull valves are labeled (h).  On Plate 17, I believe the hull valves are labeled ( i ) and not (f)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Aug , 2014, 22:13
Hello Mr. Tore,


I have a question about the Blowing Valve...  The one indicated on your drawing has another valve a little down and to the right (not Labeled)?  Is that unmarked valve the actual Blowing Valve?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Aug , 2014, 23:58
Don.
 The valve nominated f by me could very well be an i . The small valve wheel down right of the common blowing valve has nothing to do with the Q common blowing valve. The blowing air goes directly via the common blowingvalve into the common Q venting/ blowing crossoverline and has only the hullvalves of the Q port and stb. as a possible separate control valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Aug , 2014, 00:40
Don. Skizzenbuch.
Ballast tanks page 230. I guess you are mixing up MBTs 1 and 5 with bow and stern buoyancy tanks. MBT 1 and 5 are both belonging to the main ballast system and plays an important role int the diving procedure. The bow and stern buoyancy tanks are above the surfaced waterline and do not belong to the ballastsystem but is primarily used for reducing the pitching on the surface in an effort (together with the flare of the Atlantic bow) to reduce the seaoverflow and spray during surfacecruising. 
The standard diving procedure for a VIIC ( not crashdive) would be: open vents for MBT 5, 2 and 4 port and stb.( when in ballastconfiguration) and 3. Then you get your bow down angle about 7-8 degrees ( using the hydroplanes as well), then after  say 4-6 seconds open the vent for MBT1. You should aim to have the tower wind deflector at the seasurface simontaneously with the stern which would give you an 7-8 degrees bow down angle, sufficient to have enough water above the propellers and aft hydroplanes for max efficiency, thus MBT 1 and 5 are indeed very important as ballasttanks. Down below is a sketch I made for the correct diving procedure and a photo I made once from a Shackleton anti submarine plane showing my KNM Kaura ex U 995 in a correct routine diving position 8 degrees bow down.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Aug , 2014, 07:12
Don.
Skizzenbuch page 96, cooling water system main engine.
I don`t fully understand the statement: "The coolingwater has two entries per cylinder to effectively maintain the proper operating temperature". Down below is a cross section drawing of the GW dieselengine having for each cylindersection an inlet branch from the common cooling waterpipe along the outboard side of the engine, just as the green pipe on your pipescheme. The green colour indicates the cooling water entering the bottom of each the cylinderjackets, flowing upwards via a cooling waterbend to each  cylindercover having an outlet to a distribution cock with a branch off to the coolingjacket of the exhaustvalve which require only a part of the total coolingwater for each cylinder, the remainder bypasses the exhaustvalve and joins the outlet of the coolingwater for the exhaustvalve before entering the common exhaustmanifold coolingjacket and then the cooling of the groupexhaust valve etc before going overboard as mentioned by you. As this system is based on a pre WW2 technique there are no thermostates, each coolingwater pipe out from the exhaustvalve has a thermometer and the engineers had to adjust the cocks in the system to maintain the correct temperatures.
 A possible confusing part of the scheme is the rather heavily drawn second pipeoutlets from the engine joining the cooling waterbends  over the manifoldflanges, end of the manifold and the bends over the flanges for the groupexhaust coolingcasings. However these pipes are only the venting(deairation) pipes of the system. The intricate deairation is due to the fact that air in the system upset the cooling waterflow and you might get hotspots and possible cracks as a consequence.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Aug , 2014, 18:59
Hello Mr. Tore,


Again Thank you...


I have corrected the info about MBT 1 and 5...  I thought someone told me that they were not part of the main ballast system.  This was contrary to what I have always understood?  Oh well, I'm back in sync with the ballast system.


As for the water cooling for the Krupp engine, that was just my dumb mistake about 2 lines (I think I may need a new pair of glasses, and probably should have that cataract surgery that I've been putting off for several years!) .. 


Thanks for the corrections


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Aug , 2014, 09:24
Don.
Just a few minor remarks to your skizzenbuch. You have some remarks to plan 13 coolingwatersystem and  mentioning the various components getting cooling. I should mention the branch off to the propeller shaft packingboxes as well. Via valve c4 they get their cooling. 
On page 47 you are mentioning the various persons at diving station in the controlroom putting the siderudder helmsman up in the conning tower. At battlestation some COs preferred to have the helmsman in the tower however at divingstation he usually was placed in the controlroom together with the hyroplane operators. At diving it is important that the bridge can be cleared for people quickly and normally the CO and lookout rush down in the controlroom. The conningtower is quiet cramped and a helmsman is a bit in the way. At surfacing the CO is normally at the navigation periscope in the controlroom giving his orders to the helmsman prior to surfacing, it gives a better communication to have him at his place in the controlroom. Thus we normally placed the helmsman in the controlroom and only some time during battle station he was in the tower. As I said just minor remarks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Aug , 2014, 16:56
Thank you Mr. Tore,


I made the appropriate corrections and I can't thank you enough for your help with my Skizzenbuch...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Aug , 2014, 00:53
Don.
Skizzenbuch fueloil watercompensating.
The simple yet ingenious system of selfregulating seawatercompensating fueltanks might be a bit hard to understand. Basically the system works in the same manner for the internal as the external watercompensated tanks. There are several reasons for using watercompensating. 1. The compensating of weight loss due to the fuelconsumption although the seawater has a higher specific gravity, the weightcompensating being plus or minus is less. 2. The free surface effect is reduced which is important particularly to a submarine. 3. It gives a simple way of transferring the fuel in the system.
The use of the saddle ballasttanks 2 and 4 port and starboard as fueloil tanks require special precautions. The mainventing system has to be blocked and secured shut. This is done by shutting gatevalves and not cumbersome blindflanges in the ventduct between the tanks. The ventduct between the gatevalve and the mainvent has a drain/ventvalve which has to be open. The gatevalve and the drain/ventvalve are operated from the casingdeck. When diving the mainvents for 2 and 4 are open permanently and not shut while being submerged as ordinary ballastventing so you let the seawater fill the ventpipe to the gatevalve, hence the open vent/drainvalve, and the ventduct is compensated and pressure equalized.
As the tanks have a HP blowing, the hullvalves for the blowing are shut and secured to prevent structure damages.
The compensating water pipes goes from the headertank to a small chamber ( about 1,5 % of the tankvolume) at the bottom of the tank., from this chamber goes a short pipe into the tank bottom and an equalizing pipe direct to the sea. The two connections are controlled by a double seated selectorvalve operated from the casing. The valve has only two positions, either to the fueltank or direct to the sea. When in fueltank configuration the Kingstons are shut and the selectorvalve open to the fueltank and thus shut to the sea.
In the ballastank configuration  the gatevalves are open, the drainvalve shut and the main ventvalve operated as an ordinary mainvent valve. The compensating selectorvalve is put in direct connection with the sea and shut to the tank thereby the headertank is equalized when diving and submerged. The HP hull blowingvalves are opened and secured. In this way when blowing the tank air or pressureized water cannot enter into the compensating system via the selector valve. The compensatingpipes ends appr 10 cm lower than the fuel venting pipe intake, acting as a waterdischarge pipe  by fueling described by you. This allows time to stop fueling and thus prevent any fuel entering the compensating watersystem.
I know it became a long story and may be a bit complicated  so I tried to make some sketches as shown below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Aug , 2014, 08:34
Don.
 Further to my post this morning I have made an additional sketch indicating the various valves involved in a fuelconfiguration of the saddletanks. As a matter of interest I made a quick calculation of the weight compensating for the difference between the saddle fueltanks filled up with fuel and empty but compensated with seawater. The total for all 4 tanks would amount to an extra weight of about 6.5 tonnes which then had to be taken out from the regulating tanks, in case of not being watercompensated the loss of weight would have been about 43 tonnes which would have to be pumped into the regulating tanks. With a total regulating tank capacity of 24,6 tonnes this would have been impossible. If you do the same for the internal fueltanks, the total weight increase by seawater compensated tanks would be about 9,2 tonnes totalling with the saddletanks 15,7 tonnes and still possible to compensate with the regulatingtanks but without seawatercompensated tanks the loss of weight would have been about 61,5 tonnes, totalling with the saddletanks about 104 tonnes lighter which had to be compensated.  This is of course a play with figures with no realistic use but is just an example of one of the advantages by watercompensating.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Aug , 2014, 23:26
Hello Mr. Tore,


Thanks again....  You sure are a wealth of knowledge.  Updating my book..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Aug , 2014, 00:19
Don.
On page 140 you have a photo of the U 995`s GW engine. On page 141 you say: " The MAN engine looks to be the new diesel engine generation...."  It could be misunderstood as you are referring to the photo of the GW engine.
Starting procedure.
You have a description, possibly mine, of the general starting procedure on page 135 . On page 101 you are referring to a startingprocedure after surfacing, possibly mine, particularly mentioning air blowing of the cylinders prior to starting to prevent waterstroke. I would suggest you include the latter in the description on page 135 because you blew the cylinders after a long stop as well not only after surfacing and particularly after schnorchling. You would always be sure the cylinder were clean and free from water as you could have an ordinary coolingwater leakage into the cylinder as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Aug , 2014, 07:33
Don.
Skizzenbuch group exhaustvalve.
 On page 97 you are using one of my bad rough sketches to illustrate the group exhaustvalve casing passing the pressurehull and the grinding of the outer (muffler) flapvalve. This sketch might give a confusing image as it is a sideview of the aft/forward outboard system connected to a sideview of an at wartship inside system. May be you should indicate a line were the outer alongship pipe is turned 90 degrees to the aft as I have tried to indicate below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Aug , 2014, 09:35
Hello Mr. Tore,


The Black and White photo was supposed to be a MAN Diesel Engine...  Note the control levers are of the MAN design.  That is the first difference I see between a GW and a MAN design.  Am I wrong on that photo?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Aug , 2014, 10:42
Hello Mr. Tore,


The outer flap valve - what drove the gear shaft to raise the plate? Was this manual or part of the pneumatic drive?


I know the inner flap valve rotational drive was manual and I assume the raising of the plate was manual as well?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Aug , 2014, 11:01
Don.
The black and white photo is taken on board U 995 as a museumboat during the last 10 years and is showing the GW engines with a few minor modification since my time on board. The starboard engine has a new type of fuel filter, the port the original. The flooring is the museumversion having  modern floorcoverings, not original. The MAN engine is entirely different. The most significant apart from the maneuvering stand is the turbocharger in the aft end, having double inlet airducts on the inboard side from the turbocharger and the double exhaust pipes to the turbocharger on the outboard side. GW engines have common airduct directly underneath the exhaust manifold on the outboard side and the exhaust goes directly overboard as the engine has a mechanical driven Roots blower. Crankcase doors on MAN are round on the GW square. Lp fuel supplypump is on the aft end on MAN and in the forward end on the GW, so I am afraid somebody told you the wrong story. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Aug , 2014, 13:44
Hi Gentlemen,

both engines - MAN and GW were designed before war, so one can not say, that MAN engine was new generation.
Moreover, one can wonder, why Kriegsmarine chose GW engine as the primary propelling unit for type VII U-Boats
(MAN engines were installed less frequently) - especially knowing, that MAN engine was lighter and had lower
fuel consumption. The answer is that MAN engines (in the 9-cylinder version) were manufactured for type IX U-Boats,
while the other factories manufactured GW engines for type VII boats.

The photos of the MAN engines can be found here:
http://u-historia.com/uhistoria/tecnico/articulos/motores/motores.htm

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Aug , 2014, 14:46
Don.
The outer flapvalve was manually shut by a handwheel,external rods and bevelgear. The inner valve was manually operated by the same type of handwheel as well. Both wheels have holes in the  wheel circle for putting in a bar thus being able to get extra torque moment for shutting. see my picture below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Aug , 2014, 17:47
Thank you Mr. Tore,


Again, I will make the appropriate changes...  I am very surprised that U-995 had two very different control levers units on the what I assume to be the original GW Diesel Engines.  That sure confused me!


Does anybody have a good high resolution isle photo of two MAN Diesel Engines in a Type VII U-boat?  I sure don't, and I don't see one on the web so far...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Aug , 2014, 00:44
Don.
I don`t have a high resolution photo but below you see the significant difference of the maneuvering stands of the two engine types, although the MAN engine of the U 166 being a IXC  from 1940- 1941 and as such having the 9 cylinder direct reversible execution, the maneuvering stand was the same as a direct reversible 6 cylinder MAN. The MAN engine was equipped with a turbocharging system which means utilizing the kinetic and thermal energy in the exhaustgases to drive an exhaust gas turbine attached to a rotary compressor in the aft end, this system could be used over the whole output range. Although the system had been known for years, the practical use was not common in the latter part of 1930, primarily because the efficiency is depending upon fairly high temperatures which was limited by the material heat resistance of the turbine blades which at that time was a material challenge. The GW engine technique was more conventional technique of the 30this with a Roots blower which only could be used at higher output and thus required a complicated system of clutches and interlocks. Moreover the specific fuelconsumption was higher on the GW engine letting the residue exhaustgas energy disappear directly overboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Aug , 2014, 07:02
Don,
A high resolution photo of the MAN 6 cylinder engine is hard to find, below is the best image I found showing a 6 cylinder MAN M6V 40/46KBB.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Aug , 2014, 10:07
Hello Mr. Tore,


Does this look like a MAN Diesel room on a VIIC?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Aug , 2014, 12:59
Don.
It is very little engine and much of the crew on the photo, but the crew is very high up head above the engine top and it is very narrow between the engines which could indicate small engines. If you look at the framing it indicates a small hull as well. I guess this could be one of the older small submarines like  type IIB, however these submarines had MWM RS 127S 6 cyl. engines and it does not look like a MWM.
I don`t think it is a MAN 40/46 as the airduct along the engine is round and not rectangular moreover there are some internal gatevalves up under the pressurehull which does not exist on a VIIC. My guess would be: not a MAN engine and not a VIIC, possibly a smaller coastal submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2014, 09:18
Don
I was able to find a more comprehensive photo of the engine assumed by you was the MAN mainengine alternative of the VIIC engine. The MAN submarine engine underwent a number of design developments from the early natural aspirated engine ,I believe in the late 1920this, via a mechanical supercharged version, to a Buchi turbo charged version in the 1930this and to the last turbocharged,intercooled high performing version having an output for a 6 cylinder version of 2000 bhp at 520 rpm. Really an advanced modern engine I believe introduced in 1944.
I  do not think this last version of the MAN engine was used in a VIIC as 2000 bhp at 520 rpm would require  quite a few alterations in both the Emotors, shafting and propellers etc.
However I guess the engine was developed for the new "Electroboats" class XXI all equipped with MAN 6 cylinder M6V 40/46 KBB being the last type of the WW2 MAN submarine engine.
Below I have a picture explaining why I assume your picture is from a XXI boat. The people are standing on a footstep attached to the engine (on the GW engine is a similar footstep which can be folded in) which fooled me to believe it was a smaller boat. Even if the airduct from the turbocharger and intercooler is not rounded as on the picture of the MAN M6V 40/46 KBB, I believe there are so many components similar to a MAN engine which justifies my conclusion the engine is a MAN M6V 40/46 KBB in a XXI boat of which I have no knowledge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2014, 09:56
Don.
Further to my todays post. Do not to use the photo of the MAN 6V 40/46 KBB,  if not any better, may be my photo of the  IXC 9 cylinder MAN M9V 40/46 as I can`t find a good photo of a 6 cylinder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 16 Aug , 2014, 13:27
Hi tore, Don et al
 
Is this photo any good to you it is from the MAN museum where they have/had this engine on display,
 
Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2014, 13:51
Jon.
I guess it shall work, it is a 6 cylinder turbocharged MAN, it is not intercooled and has even a VIIC model at the step. Funny crankcasecovers though, I am not sure if they are expansion vents for possible crankcase explosions or not.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Aug , 2014, 18:25
Hello Mr. Tore and Jon,


I had that photo of the MAN Diesel, but I didn't notice the model U-Boat setting on the step...  Apparently Mr. Tore's eyesight is much better than mine...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Aug , 2014, 19:05
Hello Mr. Tore,


Could you post the one photo with the crewman is shorts cranking the outer exhaust flap valve hand-wheels.  I believe the photo I had with the two crewmen cranking the inner exhaust flap valves in the back of the diesel room.


Was the crewman is shorts in a VII or a IX?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2014, 23:01
Hello Mr. Tore and Jon,


I had that photo of the MAN Diesel, but I didn't notice the model U-Boat setting on the step...  Apparently Mr. Tore's eyesight is much better than mine...

Regards,
Don_
Don.
That`s possibly because I am a 1929 model ;D ;D !
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2014, 23:12
Don.
Here is the photo, but remember it is most probably  type XXI boat and definitely not a VIIC. As I said I don`t think the intercooled MAN was ever used in a VIIC as the output max cont 2000 bhp against the VIICs 1400 bhp and max. cont revs 520 against VIICs 480 rpm would be too much for the existing shafting and E-motors of the VIICs. Moreover the torsional vibrations would probably be different.
 As to the inner or outer flapvalves I cannot comment because I don`t know the XXI, but I guess they are the same valves on both photos  only that the photo of the man in shorts is taken from aft towards the bow and the photo of the two men  is taken from forward towards aft. You can see that on the intercooler of the latter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Aug , 2014, 21:20
Hello Mr. Tore,


You have discussed a normal dive with an angle of about 7 - 8 degrees...  What are the differences if this is an ALARM - Crash dive?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Aug , 2014, 01:14
Don.
The German alarm dive is a typical wartime manoeuvre and required a highly trained crew to perform, it is not a matter of divingangle alone. There are several ways to carry out crashdives, some potentially dangerous like preflooding the ballasttanks and excessive diving angles. Generally you may say a crashdive required a combination of speed (hydroplanes lifts) and flooding. Crash dives are performed under roughly 3 major circumstances 1. Dieselcruising on the surface, when you have the speed ( hydroplane efficiency), as well as the Q filled and the submarine is prepared for diving. 2. After surfacing and during exhaustblowing of ballast tanks, that`s why some COs preferred to use one of the diesels for propulsion to have a surfacespeed rather than an e- motor having much lower output. 3. At the surface, charging the batteries, some CO preferred to have a dieselpropulsion as well. Under all conditions the submarine is prepared for crashdives in hostile waters and possibilities of suprise attacks. The schnorchelling made these crashdives a bit easier.
Basically the first stage, from a divingangle point of view, is the normal 7-8 degrees as you want to have sufficient water above your propellers and hydroplanes all the time. As soon as you are below the surface and you want to go deep, you start  blowing Q at 10 meters as previously described.  At approximately 20 meters controlroom reading you turn the bow down between 8 and max. 30 degrees depending upon circumstances, watching the bow depth carefully, at 25 degrees bow down it is some 30 meters wc pressure difference between bow and stern, before eventually flatten out. See my sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Aug , 2014, 12:25
Hello Mr. Tore,


Excellent...  I will add this to my Skizzenbuch and I believe it's about finished.  I can't thank you enough for the information and the education...


Kind regards,
Don_


PS
Credits for my book...


I know Mr. Tore's full name, City?, Norway, Rank and dates from & to served on Haura (ex U-995)
I know Maciek's full name, Warsaw,Poland, I called him the Professor because he really knows the German documentation and he translated most that's available.
I know Simon's first name only.  City?, New Zealand, I used a few of his excellent drawings. He is quite talented and has an eye for details.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Aug , 2014, 13:07
Don.
For the sake of order, when U-995 served in the Royal Norwegian Navy she was named KNM (Royal Norwegian Navy) Kaura having pennant no S 309. I live in Bærum next to Oslo. Good luck with your skizzenbuch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 18 Aug , 2014, 13:35
Hello Mr. Tore,


Excellent...  I will add this to my Skizzenbuch and I believe it's about finished.  I can't thank you enough for the information and the education...


Kind regards,
Don_


PS
Credits for my book...


I know Mr. Tore's full name, City?, Norway, Rank and dates from & to served on Haura (ex U-995)
I know Maciek's full name, Warsaw,Poland, I called him the Professor because he really knows the German documentation and he translated most that's available.
I know Simon's first name only.  City?, New Zealand, I used a few of his excellent drawings. He is quite talented and has an eye for details.

Hi Don

Simon J Morris, Castle Hill, New Zealand

Don, I live in a small village in the mountain call Castle Hill (only about 20 people), Christchurch (about 1½ hours drive away) is my nearest small city (Pop. 350,000).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Aug , 2014, 16:47

Hello Mr Tore,


Past 1497, Page 140 "The gate valves and drain valves are operated from the deck casing"....


To me, it looks like the gate valves hand-wheels are located inside the pressure hull and the drain valves for the common duct must be opened from the out side under the deck casing?


Am I all wet again?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Aug , 2014, 00:53
Don.
I guess you are referring to plate 16 and understand your confusion. The drawing is a bit misleading as some valves like the emergency shutoff valves c are drawn correctly having the valvespindle through the pressure hull indicated by a double line crossing the spindle and the gatevalve spindles d not crossed by a double line, indicating to be operated outside the pressurehull eg. from the casingdeck, I guess  by a T bar, thus no wheel. However the confusion is, the Kingstons and the main ventvalves for some reasons are not marked with a double line even if they are operated from inside the pressurehull. If you look at some of Simons excellent drawings shown below it clearly indicates how the system works. I believe the valve wheels are removed and the valve spindles are operated by a T bar as  mentioned and can be seen on many photos.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Aug , 2014, 01:13
Don.
Although you are about finished with your Skizzenbuch I`ll mention a small but important detail of your description of Plate 8 page 58.  When fuelling, the seawatercompensating system is open as well, the selector valve is in fueltank configuration eg. direct connected to the fuel/ballasttanks 2 and 4. When fuelling deliverypressure is exceeding the compensating pressure the compensatingwater is forced overboard via the header tank. It is important to prevent any fuel to enter the system ( danger of oilslick) thus the compensating waterpipe in the fueltanks is at the lowest point in the tanks approximately 10 cm. lower than the the testpipe to ensure the man checking the testcock has time to shut of the fuelsupply. Due to this it is always some residue compensatingwater left in the tanks.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Aug , 2014, 12:17
Thank you Mr. Tore...


I have added a graphic and a paragraph to Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Aug , 2014, 14:18
Don.
Good. As to the high voltage general electric scheme  I got the advice to have it scanned, unfortunately in the rural remote area of my farm I have no possibilities of getting that done. When moving back to civilisation some time in October I`ll  try to have it done.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Aug , 2014, 21:08
Great news Mr. Tore about scanning the document...  That is definitely one item I would like to place in the Wallet folder in the back of my personal Skizzenbuch.


I believe scanning the High Voltage General Schematic will save something that is most-likely a one of a kind document; something like preserving a Rembrandt, or a Picasso (I may be exaggerating some what), but I'm glad to see that happen...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Aug , 2014, 23:59
Don-
Well, comparing a shabby 2nd. copy of a bad blueprint with an original Rembrandt is may be a bit far fetched. Anyhow it can`t be better than my bad drawing. But seriously these were the kind of drawings we had to use to keep the boat running at that time. If worst come to the worst we might use the good old mail, however it is my intention to donate same to the Naval Museum where the rest of my books,notes and drawings are. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Sep , 2014, 07:04
Museum U 995 schnorchel.
We have many times mentioned the differences between the original U 995 and the museumexecution. The schnorchel is one of the differences. In fact U 995 did never operated as a schnorchel boat during WW2. She was still at the yard in Trondheim , Norway installing the schnorchel May 1945. The original schnorcheltype had the ringfloat type of air intakevalve and operated with this type of schnorchel all the time under Norwegian flag. For some reasons the museum U-995 has got an incomplete execution of the hinged type float mast.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Sep , 2014, 18:06
Hello Mr. Tore,


a few questions about Schnorcheling...  (ah snorkeling)?


U-995...
Q1.  What was the top speed while schnorcheling?
Q2.  Could the attach periscope be up at that speed?
Q3.  Were they not completely blind at top speed?  (I would not believe they could listen for enemy or targets while the Diesel Engine/s were running submerged).
Q4.  Could they run both diesel engines while Schnorcheling?
Q5.  If schnorcheling and attached by aircraft, did the schnorcheling mast up present any problems while diving for safety;  depth limitations or maneuvering issues with the mast up?
Q6.  Could they lower the mast while diving or while submerged?


We need some more activity on this thread... I may update my Skizzenbuch with more great information from Mr. Tore...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Sep , 2014, 01:09
Don-
Snorting.
Schnorcheling is the German word for a Dutch system allthough known for many years before the dutch invention. In RN English the word used was snorting.
Q 1. The theoretical construction strength of a VIIC snort mast could take max. 6,5 knots I believe.
Q 2. We used the periscope while snorting.
Q 3. We were not completely blind, but one of the big disadvantages while snorting, regardless the speed,  was the diesel engine noise and you could not use the passive sonar.
Q 4. You could run both diesels while snorting but limiting factors like underpressure, backpressure and speed would not give you much advantages of doing so.
Q 5. You could could go deeper while snorting shutting down the diesel immediately. and you would lower the mast while doing so.
Q 6. We mostly raised and lowered the mast while submerged, but you could do this surfaced as well.

A remark concerning my personal experience. We had an event before my submarine training course in UK, may be you recall the disaster of HMS Affray a British A class submarine. The training class 2 years ahead of mine was on board on a final snorting training in the English channel when she disappeared with all hands lost including the whole trainingclass, totalling 75 men. She was eventually found with the snortmast raised but broken. The discussion of the reason for the disaster was at my time still going on and in spite of the German snorting instructions I was a bit cautious as to pushing limits while snorting. One of the alternative snort propulsion, direct dieseldrive, we found a bit difficult to practise as the boat was no easy to handle, so we preferred electric propulsion running one diesel and generator as battery charger.
 However as to HMS Affray I guess the conclusion was battery explosion and the broken snortmast was a secondary  damage. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Sep , 2014, 03:00
Don,

some interesting information about German Schnorchel (i.e. the operating modes) you can find in this instruction:
http://www.ubootwaffe.pl/images/okrety/instrukcje/chrapy/preliminary_snorkel_description1.jpg
http://www.ubootwaffe.pl/images/okrety/instrukcje/chrapy/preliminary_snorkel_description2.jpg
http://www.ubootwaffe.pl/images/okrety/instrukcje/chrapy/preliminary_snorkel_description3.jpg

Other useful information can be found in these operational orders:
http://uboatarchive.net/BDUOrder1.htm
http://uboatarchive.net/BDUOrder2.htm

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Sep , 2014, 22:18
Hello Mr. Tore and Maciek,


Thank you all for the information on the Schnorchel (I learned how to spell in right this time)...  I'll have to go back and correct the spelling in my Schizzenbuch!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Sep , 2014, 00:53
Hi Gentlemen,

regarding to Schnorchel, I have attached the Schnorchel Befehlsprache - list of commands used when Schnorcheling.
Some time ago, I have written article about Schnorchel in Ubootwaffe:
http://www.ubootwaffe.pl/okrety/wyposazenie/chrapy
It is in Polish (I do not have time to translate it), but maybe you will find interesting drawings or photos, and if you will get
interested in some part, I will be happy to translate or explain it.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Sep , 2014, 13:34
Hi Maciek,


Great articale...  Not a problem with the translation; Google Chrome asks if you want this page translated and does so...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Sep , 2014, 20:18
Gentlemen,


Does this photo look like the BOLD decoy launcher which is located in the Aft Torpedo room...  I believe the long red handle is to unlock the inner door and it swings open on the hinge.  The bolt decoy in loaded into the tube and the inner door is closed and locked.  Then the red hand-wheel opens the outer door and the bolt decoy is launched with HP air.  The only thing I don't see is the triggering device.  Am I close to correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2014, 00:38
Don.
It is indeed a decoylauncher which the Germans called a Pillenwerfer. The device did not have much of a trigger but rather a handwheel, the blue coloured wheel on your photo, admitting air behind a launchingpiston inside the tube. It is an interlock preventing the outer cover to be opened unless the inner cover is shut. The pipeconnection on the top is the launch airconnection, while the lower small pipe is the drain. Otherwise you are pretty much correct in your assumptions. The Pillenwerfer was used for many purposes like launching canisters filled with magnesium pellets which, when in contact with the seawater produced bubbles giving a sonar echo resembling a submarine. In peacetime we very often used small rockets indicating a torpedo launch during exercises. It could of course be used for launching distres-signals as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Sep , 2014, 01:26
Hi Gentlemen,

my small addition to Tore's info:

external photos of the Bold ejector: http://models.rokket.biz/index.php?topic=1150.msg14860#msg14860
drawings: http://u-historia.com/uhistoria/tecnico/visitaguiada/lanzasenyuelos/lanzasenyuelos.htm

Many pieces of info you can find on the uboatarchive.net website, searching the term "S.B.T." (Submarine
Bubble Target).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Sep , 2014, 01:19
Don.
Trimming pump/trimcontroller.
I just happen to check you explanation of the system on page 30 in your Skizzenbook and believe you should include the trim flowmeter in your explanation. The reason is that when the pumpman operated the pump and the trimcontroller his eyes were fixed on the flowmeter in order to compensate the correct amount which some time could be within narrow limits. F.inst. as I have mentioned before, prior to the order "Diving station" the pumpman got the order from the officer on watch: pump 400 liters from aft to forward as this was by experience the exact amount needed to compensate the movement of the crew for such an order.
The trim flowmeter is correctly marked on the sketch by the green arrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2014, 11:54
Thank you again Mr. Tore,


I have added the information to page 30.  Usually over the weekend, I update the main Skizzenbuch PDF file and copy it to dropbox and you have access to any updates. 


I just got a response to an email to the U-Boote Museum in Cuxhaven, Germany, and they have a manual that is a treasure trove of information on the switchboards and e-motors.  With a great deal of help from Maciek, I will most likely have to re-write much of the switchboard and e-motor section.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Sep , 2014, 01:26
Don.
Skizzenbuch fueloil supply pipe.
On page 67 you show a fuelsupply scheme of the fuelsupply from the daytank/ settlingtank to the engine driven fuel supplypump. This might be a bit confusing for an ordinary VIIC as the system shows a MAN engine configuration having the enginedriven supply pump in the aft end of the engine. The most common system is that of the GW engine having the fuel supply pump and filters up front of the engine. The picture below shows the GW system with cocks, filters and pump. After the double filters the supply pipe goes to a knifefilter (with drain to the dirty fueltank) behind the HP fuelpumps ( on top of the camshaft casing) and then to the common supply pipe to the HP fuelpumps.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Sep , 2014, 20:35
Thank you Mr. Tore,


I updated Skizzenbuch and uploaded the latest PDF file to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Sep , 2014, 07:49
Don.
Your Skizzenbuch page 40 give a description and a photo which might give a wrong understanding, further the plate 7 and plate 17 could give an impression that venting and blowing Q is done via two pipelines.
 Both systems are combined in one crossoverline between port and starboard Q tank. On starboard side you have the red wheel which is the main blowingvalve for both tanks and is not involved in the venting as your nomination on the photo :"air supply, ventvalve drive shaft".
 When the main blowingair valve is opened air is admitted to the common crossoverpipe and to both tanks via the hullvalves and both Q`s are blown..
 When venting, the master blowvalve is shut and the common portside ventvalve is open and vent the common crossoverpipe for both tanks into the boat via the common muffler.
Thus blowing both Q tanks is only done by the red handwheel on starboard side and venting both Q's is only done on the port side by the lower T handle ventvalve to the muffler.
Below is a sketch trying to explain my remark.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Sep , 2014, 23:38
Hello Mr. Tore,


I don't know if you have the current version of Skizzenbuch with 322 pages.  I believe we covered the issue of the Q tanks and there was an adder page 43 in the latest version.  However, If page 43 does not look good, then I will definitely go and replace it.  Can you download the latest version and let me know if you see any problems with page 43?


Skizzenbuch has started to increase in size; which is a good thing because I'm getting really good information.  Just Today, I got a response from the Uboote Museum in Cuxhaven Germany and they are going to copy an Electrical Engineering Manual with supporting drawings.  This is something that Maciek and I have been searching for in the past several years.  I can see there will be easily a dozen or more added pages.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Sep , 2014, 01:17
Don.
Sorry I missed your latest version of the Skizzenbuch where you have the correct system of the Q. A minor remark is that you have marked the handles for the diff. manometer cocks as cut off valves may be you should add " for the diff manometer". I`ll start checking the latest version of the Skizzenbuch as from now. It is quite a comprehensive work to get everything into such a book and I guess you shall end up with a few extra pages before it is finished.
Good to hear you are getting along with your Electrical Engineering Manual and supporting drawings. Kindly advice if my high Voltage scheme is still needed when I am back to civilization in October.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Sep , 2014, 17:46
Thank You Mr. Tore,


I corrected the photo labeling on page 44 and updated Skizzenbuch...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Sep , 2014, 07:17
Don.
I hope I have the latest edition of your Skizzenbuch and am referring to page 157. On your image of the outer and inner main exhaustvalves it looks as you have mixed the inner valve with the outer. The inner valve is the aftmost red wheel operating a flapvalve being fully open when the relevant diesel is blowing the ballasttanks. The outer flapvalve just before the exhaust silencer is used for regulating the exhaust backpressure for blowing.
 The inner valve has a double turning shaft one acting as a fulcrum for the flapvalve, the other as a shaft ending in a square outside the gearcasing. On this square you can put a ratchet bar for grinding the valvedisc against its seat by hand. Very much the same way as the outer exhaustvalve except the latter in driven by the pneumatic motor. See image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Sep , 2014, 17:36
Hello Mr. Tore,


I am in the process of correcting page 157...  When the engine room engineer is adjusting the Exhaust Silencer flap valve to establish the correct blowing pressure of 1.5 atm is he using the pressure gauge mounted on the back bulkhead (barely visible)?  What is the gauge ahead of it (most prominent in the photo) used for?


Thanks for picking out this error on my part.  I guess I was fixated on the pressure gauge in the center of the photo...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Sep , 2014, 00:37
Don.
I don`t think so Don, this manometer is marked for the normal LP air pressure and I guess it is used for the pneumatic/air system of the main clutches. As far as I remember, the exhaustpressure would be checked by the manometer in the instrument panel up front of the engines. I am not sure if I understand you question referring to the most prominent gauge are you referring to the fuelmeter for the day/settlingtank?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Sep , 2014, 06:38
Don.
In your Skizzenbuch page 59 you are stating: "note the internal aux. luboil pump is not used to fill the fuel oiltanks". Under normal circumstances the fuelling station is able to furnish adequate fuellingpressure, however the ¨VIIC  systems are generally  quite diversified and able to handle a number of situations. F.inst. if you are fuelling from a source not able to supply adequate pressure to force out the compensatingwater you use the aux luboil pump. Likewise if you for some reason should empty the fuel in the fueltank without being able to use compensatingwater pressure f.inst during docking or maintenance, you might use the aux. luboilpump as seen on my two sketches below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Sep , 2014, 19:43
Hello again Mr. Tore,


I made the corrections to Page 157 and that location is in the 2nd third of the book (not a problem).  I had an issue with "MS Word" crashing and corrupting my file, so I had to break up Skizzenbuch into 3 parts.  I also corrected page 59 and added your excellent drawing, but that involved deleting a print and moving things around to get everything in the 1st third of the book's 108 pages.  Pages 57 through 69 were moved or changed.  However, I believe the changes make everything flow much better as far as information and presentation goes.


I uploaded the latest version of Skizzenbuch to dropbox with all your changes to date...


I really appreciate all your extra effort in making Skizzenbuch a good source of information on the type VIIC U-Boat.  At 322 pages, I have to go back and read what I had written (I think sometimes I have a senior moment!)....


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Sep , 2014, 02:00
Don.
You idea of a Skizzenbuch is great but ambicious as it is almost impossible to incorporate every thing. To day I am referring to page 76 and your description of the saddle tanks fuel configuration plate 16. May be a short explanation of the system would be helpful. As mentioned before plate 16 is a bit unclear with regard to which valves are inside and outside the pressurehull. As a rule the valves operated inside the pressurehull have a double line crossing the valvespindle. However the Kingstons marked on plate 16 have not.
The venting system of the saddletanks has a special arrangement as the tanks a stretched over a long area of the submarine. As the tanks have a common main vent appr. midships this create a problem particulary when diving at a steep angle down as air shall be trapped in the aftermost part of saddletank 2 port and stb. ,see my sketch below. To overcome this is a small crossover residue ventpipe having a common ventvalve in the aft part of the tank. The vent can be operated both from the controlroom and the engine room. Like the common main ventpipe for the saddletanks the residue ventpipe has individual gatevalves to be shut in fuelconfiguration. These valves are, like the gatevalves in the mainventpipe, operated from the casingdeck outside the pressure hull.
The gatevalve on the photo you are assuming is the ventpipe gatevalve D1 for the residue venting, is the port forward engineroom bulkhead valve for the shipventilationsystem and has nothing to do with the saddletank residueventing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Sep , 2014, 19:15
Hello Mr. Tore,


I know I can't put everything in Skizzenbuch.  However, my idea is to create a single book that gives the reader (now me!) a good understanding of the design and functionality of the Type VIIC U-Boat.  I am especially grateful to you because I don't believe there is anyone else left with the knowledge you have on the Type VIIC U-Boat.


I have updated Skizzenbuch with your latest suggestions, and posted the latest Skizzenbuck into dropbox...


Regards,
Don_


PS:  I don't believe the U-Boote-Museum has the large ship print that you have because that came from the builder.  Their books are of the Kriegsmarine training variety...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Sep , 2014, 01:57
Don.
I have just had a quick glance on your latest edition of your Skizzenbuch and have a few minor remarks. On page 40 you have still a photo marked as valves controlling the Q tanks.The starboard main blowingvalve is marked as ventvalve drive shaft, as this is wrong I suggest you name it the common main blowing valve for Q. On the photo of the port controllingvalves for Q is the main vent valve marked as valve in the line to the muffler below, which is correct, but I believe it would be easier to understand if same is named as the common main vent valve for Q tanks.
On page 157 the handwheels for the inner and outer main (Group) exhaustvalves are interchanged. The aft wheels marked as external flapvalves are the internal, and the forwards marked as internal flapvalves are the outer flapvalves before the silencers . I guess the confusion is due to my photo where I for some reason have erroneously have marked the inner flapvave gearsegment as Casing for EXTERNAL EXHAUST FLAPVALVE SHUTTING GEAR SEGMENT, it should be internal, please correct. Sorry :-[
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Sep , 2014, 21:31
Hello Mr. Tore,


I corrected page 40 and 41 with your recommendations...  Thank you.


The right insert photo of the "Casing for the External exhaust flap valve gear segment" looks to be positioned near the aft engine room bulkhead, and you can see part of the pneumatic motor.  This looks to be correct to me???  Am I missing something?


Both the external and the internal exhaust flap valve are manually controlled by the hand-wheels which turns a shaft with a worm gear to drive a segment that opens or closes the exhaust flap valve.  Is this correct?


If so, then would this photo be OK?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Sep , 2014, 21:54
Hello Mr. Tore'


After reviewing your diagram of the flap valves, I believe there is a gear in the casing and not a segment.  I think that part needs to be changed,,,  What do you thing?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Sep , 2014, 22:49
How about this....  Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2014, 00:03
Don.
The image correction 4 you are referring to is erroneously marked external exhaustflapvalve by me and is the internal main (Group) exhaustvalve operated by the red handwheel. The handwheel turns a spindle with wormgear engaging a gearsegment attached to a hollow fulcrumshaft  , (yellow on my sketch) connected to the rotation center point of the the flapvalve disc having a geared rim. The shaft ends in a valveindicator (pointer) forward outside the gearsegment casing, showing the position of the valvedisc. Inside the fulcrum shaft is a (black) shaft with wormgear engaging the valvedisc gear rim  for turning (grinding) the valvedisc against its seating. The shaft is protruding outside on the aft of the valvecasing and ends in a square for a ratchet bar for moving (grinding) the valve disc. So the inner main exhaustvalve is ground by hand. The outer main exhaustvalve (before the silencer) has a similar arrangement but the shutting and opening of the valve is done by the wheels forward of the inner mainvalve handwheels. The operation transmission to these valves are done by bevelgears and rods outside the pressurehull and the grinding is done by the pneumatic motors driving rods and bevelgears turning the valvedisc in the valvecasing outside the pressurehull. Basically the same way as the inner valves but pneumatically driven instead of the hand ratchet rod. Thus the aft handwheels are for the inner valves, the forward handwheels are for the outer. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Sep , 2014, 13:55
Hello Mr. Tore,


Does this drawing look OK?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2014, 14:23
Don.
This looks excellent except the arrow to what you call internal flapvalve gear segment point to the pneumatic motor for the drive of the grinding rods for the main outer exhaustvalve disc.  As the combination of  shutting and grinding of the valve makes it difficult to understand I made a sketch below showing the working principle of the mechanism for the inner valve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Sep , 2014, 20:51
Hello Mr. Tore,


I made the arrow longer so it is touching the segment casing...  Uploaded corrections to dropbox...  The location of the flap valves internal and external is a bit confusion because the external exhaust flap valve casing is outside the pressure hull and farther back. However, it's the drive shafts that place the controls farther forward ahead of the internal exhaust flap valve controls in the diesel room ceiling. :o


I liked the last diagram you posted showing the internal exhaust flap valve drive segment...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Sep , 2014, 23:40
Don.
I just checked you to days corrected edition of the Skizzenbuch in the dropbox. I still think you should lengthen the arrow for the gearsegment of the inner main exhaust valve pointing at the pneumatic motor for grinding outer main exhaustvalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Sep , 2014, 12:46
Hello Mr. Tore,


I did take your suggestion and lengthened the arrow  However, I posted the old photo back into Skizzenbuch.  I posted the correct photo and updated Skizzenbuch in dropbox.  below is the photo that is now in Skizzenbuch... 


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Sep , 2014, 14:31
Don.
That`s it ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Oct , 2014, 01:38
May be we get a bit serious in the play of VIIC details. The other day I was looking into a cross section of MBT 3, suddenly this picture turn up in my head. Might be a new avatar? ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 Oct , 2014, 04:21
May be we get a bit serious in the play of VIIC details. The other day I was looking into a cross section of MBT 3, suddenly this picture turn up in my head. Might be a new avatar? ;D

Haha, Tore, great picture :)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Oct , 2014, 06:39
Don.
All of a sudden I remember a manometer for the exhaustgaspressure in the exhaustgasmanifolds which could be used for adjusting the exhaustgas blowing pressure as well. It is placed on the forward stb. side of the housing for the Roots blower. The manometer shows the pressure in ATU (overpressure) and thus have scale from 0 to 1. I am not sure but may be it was installed in relation to the schnorchel installation. In addition, the engine exhaustmanifolds have a reliefvalve up front of the manifold. Particulary during schnorcheling these valves could lift, letting in an unpleasant dark exhaust into the engine room.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Oct , 2014, 02:00
Don.
Having looked through your Skizzenbuch I wonder why you have not included a main item as the schnorchel system. Introduced in August 1943 as a counter act to the allies air superiority it was an important conversion for the German uboats in 1944-1945. As we have discussed before you can`t include everything, but I guess this is an important detail of the submarine WW2 warfare which is worth while to include.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Oct , 2014, 17:35
Hello Mr. Tore,


I am still working on the schnorchel addition and will update Skizzenbuck in a few days...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Oct , 2014, 18:02
Hello Mr. Tore,


Perhaps you can help me with this diagram...


1.  The hydraulic pressure oil cylinder has 150 and the greek letter theta?  What does that theta mean?
2,  How do they know the schnorchel mast is fully up or down?  Would that cause an increased pressure reading on the manometers so they know the mast is fully up down?
3.  Does the throttle switch control valve determine the direction of the piston drive? Mast Raise is high pressure oil and mast Lower is hydraulic oil back to the source inside the pressure hull.
4.  I believe things are reversed when lowering the mast.  Is that true?
5  Any other comments about the diagram?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2014, 00:44
Don.
1. This is the international letter for diameter in this case 150 mm.
2. It is an indicator up forw. port side in the control room see picture below.
3. Yes it is a handoperated switch connecting the "raise" side of the piston to the hydraulic pressure system and the "lower" side to the hydralic oilreturn see picture below.
4. Yes
5. The sketch is not showing the handle for lowering/ raising the mast, see my picture.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2014, 08:55
Don.
Before we go into further details may be we should discuss the basic systems of the Schnorchel. I don't`know your knowledge of the systems, so have me excused for going into the some items which might be too obvious to you.
 As a consequence of the great losses in 1943 due to allied air superiority, the germans had to do something to protect their Uboats and looked into a dutch system from before WW2  called the "sniffer" translated.  The system had to be adapted to the existing Uboats so they had to utilise the existing systems. Thus they had to make some compromises.
In the end of 1943 their system was ready to be installed in the frontline boats. The mast could not be telescopic that would require major changes, so they made a hinged type of schnorchel which could be folded down in the casing ( for VII Cs port side of the forward conningtower). The system utilised the existing exhaust blowingsystem for the ballasttanks using the same pipes up to the distribution chest outside the pressurehull  starboard side of the forward conningtower casing. Right before the chest it is a branch off to the schnorchelmast. In order to pass the distribution chest they had to let the pipe to the schnorchelmast go above the casingdeck ending in a schnorchel shut off exhaustvalve before the pipe goes under the deck and connects to the schnorchelmast.
The air intake ( for the first generation of the system) utilise the existing outboard ventilation airduct in the casing outside the pressure hull. The air enters the schnorchel mast via a top floatshutting valve being either  ringfloated or  hinged floated controlled.
Half way up at the conning tower appr. at the spray deflector the mast air pipe engages a fixed pipe on the conningtower via a rubber flange. This pipe goes to a drainvalve operated from the control room just before it enters the ventilation intakevalve inside the conning tower casing. Then it follows the ventilation duct still outside the pressurehull almost to the pressurehull inlet valve and have a cross over to the dieselair duct. The airinlet follows the dieselair hullvalve into the engine room. The reason for this arrangement was that in case of massive water intrusion, the ventilation fans could be destroyed whereas the large dieselair ducts ended near the bilges. Quite a few VII Cs had this arrangement.
This system was not quite satisfactorily and a modified new system was designed. The new system kept the arrangement for the exhaust, which is quite simple, but the air system was changed. The pipe on the conning tower was removed instead came a hollow schnorchel fulcrumshaft and the air was lead through this shaft and aft under the casing directly to the dieselair duct. One small detail though, it was not sufficient space for the bend leading the pipe aft so they had to make a hole in the casing to let the pipe turn aft outside the casing, hence it was easy to see which U boat had the new design, see my picture.
Puh! some long story, just ask if something is unclear may be I can answer ;D !
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Oct , 2014, 09:46

Hi, I'm still alive and still busy with my game. mostly working on graphics stuff and other non-simulation related things: https://www.youtube.com/watch?v=1IAL_24bfb4&list=UU03RMMpKkHkZVROUHFTWYVA

Don, the Skizzenbuch, any chance to get a copy of it?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2014, 10:24
Mark.
Good to see you are still around. I can`t stop being amazed by the graphics. One thing struck me though, to me it seems like the anchorbay is a bit high up on the U 96.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Oct , 2014, 10:31
oh  :o


you mean the dent / hole for the anchor? It's on the same position as on the drawings I've used hmmm. Will look into it when I finish the model.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2014, 11:58
Mark.
Yes it looks a bit strange to me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Oct , 2014, 12:17
Yes you are right. It's a comparable tricky part I hope I can fix it without running into new problems.


*searches for his time machine to travel back and change original pre-wwii type vii plans*
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Oct , 2014, 15:07
Hello All,


The type VIIB and early VIIC had the standard bow.  Then the Atlantic bow was introduced and that widened and raised the bow.  I have the German edition or Rossler's book Geschichte des deutschen U-Bootbaus and the included fold out schematics show the obvious difference.


Regards,
Don-
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Oct , 2014, 23:44
Hello Mr. Tore,


I just posted the latest version of Slizzenbuch into dropbox with our first attempt at including the Schnorchel,,,  I typed schnorchel so many times that I'm even spelling it your way.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Oct , 2014, 00:15
Don.
Not bad, your are learning details of the VIICs and you are picking up the German language at the same time ;D .  I`ll have a look and revert later my time today.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 04 Oct , 2014, 00:29
The type VIIB and early VIIC had the standard bow.  Then the Atlantic bow was introduced and that widened and raised the bow.  I have the German edition or Rossler's book Geschichte des deutschen U-Bootbaus and the included fold out schematics show the obvious difference.


I think I scanned the fold out schematics from those 2 Rössler books (and the plan on page 166/167 of book #1) to build the model - something must have gone wrong.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Oct , 2014, 01:47
Don.
On page 311 you have photos of the old and new version of the schnorchel  piping system. As you shall see from my text the old exhaust system was kept and only air inlet was changed on the new system. So I wondered why you had marked the airpipe on the tower and the protruding airbend out of the casing exhaust. Then I realized that I had posted  a wrong picture which should have been deleted as the bend and pipe were marked wrongly exhaust. Sorry about that but sometimes when you handle a lot of pictures it is hard to see such details in the process of posting.
On the system drawing page 312 you have copied my sketch of the old air inlet system (blue) correctly apart from a small branch off to the ventilation hullvalve. As mentioned in the text, the ventilation airduct hullvalve in schnorcheling mode is shut to prevent waterintrusion into the ventilationfan thus all the air goes into the diesel airduct/hullvalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2014, 17:20
Hi Mark,


The book page 166/167 is the (1940) General plan with the standard bow.  However, the separate large fold out plans in the back of the book Tafel IV and Tafel V are for the VIIC (1944) General Plan and this is the Atlantic bow.  My book set came with separate large folded prints just placed in the back of the book Volume (Band) 1, Tafel I through IX - and Volume (Band 2), Tafel X, XI, XII, XIII, XIV, XV, XVI, and XVIII. There was no XVII??


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 04 Oct , 2014, 17:38
There was no XVII??



This is Tafel XVII:



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2014, 21:40
Hi Mark,


I looked again and I do have XVII... Apparently I didn't check the back of XVI when I was going through the fold out sheets.


Regards,
Don.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2014, 21:54
Hello Mr. Tore,


I believe I made all the corrections to the Schnorchel section of Skizzenbuch and uploaded to dropbox.  I also cleaned up the first few pages wording, and added photos of U-995's schnorchel installation and the mast guide and holding mechanism.  When I was first doing the schnorchel write up, I was wondering what held the mast in place other than water friction when the U-Boat was moving forward.  Then when I was looking at the photos of U-995, I noticed a raised section at the inside front of the guides and a vertical shaft in back of the guide metal housing. That led me to the conclusion that the guides spread apart, then clamped around the mast under spring torsion when it was at 90 degrees...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2014, 22:05
Hi Mark,


Thanks for your effort...  By the way, I have Rossler's book in English (only a single thick book with small print size), and the drawings are bound in the back of the book and take 2 pages.  However, there are only 12 schematic.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 01:33
Don.
I checked to days Skizzenbuch on the Schnorchel which as far as the airpipe goes is OK.
 I am not sure of your description on the homing of the Schnorchel though. The U 995 has many modification from the original and the schnorchel is a major one. The mast air valve is a hingefloat, original is a ringfloat, the schnorchel lockingpin drive rod from the control room is removed, the raising and lowering system is partly removed just to mention a few items. The schnorchel installation make use of the existing hydraulic system with a branch off and shutting valves from the periscope pipes. The mast is secured in a downright position by a locking clamp operated from inside the pressurehull portside up near the CO cabin. Likewise the mast is secured in the homing guide at the towercasing. This lockingpin is operated by a wheel connected to rods from the controlroom port side up. The transmissionrod have different positions at the various boats, some goes inside the towercasing, some partly inside or in an outside protector casing but all rodversions  protrude outside the casing at the spraydeflector  before they are engaging the locking device. I have tried to incorporate most of this in the image below the schematic sketches made by me are my assumptions which might deviate from the real design.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 02:09
Mark and Don.
Atlantic bow. Simon has done some research on this and his conclusion is that the Atlantic bow start to raise at frame 104 and reach the full height at frame 111. The anchorbay is located between frame 103 and 106 so I don`t believe this has a significant visual effect on the position of the anchorbay in relation to the casingdeck.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 03:33
Somehow the whole anchor bay went to the wrong position and it is a bit smaller than the original. No idea how that could happen.
Tore is Mr. Eagle-Eye.


 

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 04:35
Mark.
This seems to be much better. The anchor bay was not a problem only to you, Revell put it quite a bit too far aft on their 1:72 buildingkit for VIIC/41 ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 07:41
fixed?


upper = repaired, lower = before



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 08:01
Mark.
Excellent. I like your two bow floodgates in the waterline on the starboard side and hope you have 3 on the port.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 08:11
unfortunately not  :(  the smaller holes are just painted and the texture is identical on both sides. I can try to add a 3rd one when the model is finalized.


I've also fixed the painting of the anchor bay to fit to the water line - I guess this is correct?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 08:38
Ok, I've made those holes real ones and added a 3rd one on the other side…



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 08:51
Mark.
Very good. May be the flood gates are a bit low in relation to the anchorbay and waterline. They are a few cm above the waterline of a VIIC/41 anyhow as can be seen on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 09:51
I think this is because of the atlantic bow - or different height of the painting of the water line?


Many WWII pictures and some models shows the holes below the waterline.

[/size]
[/size][size=78%] [/size]
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 11:36
mark.
Absolutely correct. I guess however one thing is fixed, the freeflood gates are the gates for the bow bouancy tank and as such they have to be right above the tankfloors, see my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Oct , 2014, 12:30
Looks like it needs to be a little deeper then
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2014, 14:32
Mark-
Hold on! Something was not correct as the buoyancy tank does not go all the way to the bow,  it is  a forepeak in between of which I believe the floodgates relates. To me it seems that the two floodgates would be situated at  the level of the rounded fore lower corner of the anchor bay about where my yellow line is drawn on my sketch below. Sorry about that :-\ .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Oct , 2014, 23:43
Hello Mr. Tore,


Thank you for the information about the Schnorchel locking mechanism.  I updated Skizzenbuch with that and the info about the location of the exhaust line and shutoff valve above the deck casing.  The latest Skizzenbuch was uploaded to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Oct , 2014, 01:36
Mark.
I had a closer look at the bow floodgates this morning and show you my final suggestion as per the images below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 06 Oct , 2014, 01:41
So, just a tiny bit lower - thanks. BTW is the anchor bay really that large?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Oct , 2014, 01:53
Mark.
 Your question on the variation of waterline. The difference in draught at the various images of VIIC might be due to many variables. salinity, temperature, ballasttanks configuration,
fuel, torpedoes, supplies etc.  You did not compensate the draught immediately and some CO liked to have a bow down trim, which was prohibited due to the danger of undercutting.
During warpatrols quite frequently you had the Q tanks filled for allowing quick diving. Thus no wonder there are photos showing different trim and draughts.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 06 Oct , 2014, 01:56
Yes, sorry I mean the painting of the waterline not the real physical water line.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Oct , 2014, 02:11
So, just a tiny bit lower - thanks. BTW is the anchor bay really that large?
Mark, I did not checked the anchor bay size. However  the lower corner aft and fwd corner high is between frame 103 to106.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Oct , 2014, 03:08
Hello Mr. Tore,


Thank you for the information about the Schnorchel locking mechanism.  I updated Skizzenbuch with that and the info about the location of the exhaust line and shutoff valve above the deck casing.  The latest Skizzenbuch was uploaded to dropbox...


Don.
I checked your to days Skizzenbuch update and it looks OK. One small item. The U 996 did not have a schnorchel during WW2. She came back from her last patrol in March 1945 to have a schnorchel installed and was almost ready end April. Thus she has never been operated as Schnorchel boat by the Germans.
Tore


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Oct , 2014, 17:59
Hello Mr. Tore,


I corrected the history of U-995 as per your information.  In Addition, I got an email from Maciek and he was kind enough to identify several errors on my part about the switchboard and e-motors and made corrective suggestions.   I believe I have made all the corrections and uploaded the latest version of Skizzenbuch to dropbox.  I may need to do some additional work on the speed controller...   That has proven to be a very difficult page!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Oct , 2014, 00:56
Don.
I checked the Skizzenbuch on the U 995 history OK. It might be of interest to you that her last and 9th mission during WW2 was in the Barenz Sea outside the Soviet Kola peninsula. She attacked the allied convoy JW-65 and destroyed an US freighter Horace Bushnell of 7.176 ts. 13th. of March 1945. Then she returned to Narvik and Trondheim Norway to have the schnorchel fitted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Oct , 2014, 22:42
Hello Mr. Tore,


I like that kind of information and I placed it on page 320 in the latest version of Skizzenbuch which I uploaded to dropbox.  I have been emailing Maciek about Rotary Converters and he gave me some excellent photos and information, so I just had to include that info.  Also. I decided to take his advice and changed the main control panel and auxiliary control panel back to switchboard and auxiliary switchboard.  I called the motor control units the Rotary Switchboards, so that covers all 3.


You know; the more I learn about the Type VIIC U-Boat, the more I find out that I don't know a lot!  You and Maciek are way beyond my limited knowledge, and I have the audacity to attempt to write a book!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Oct , 2014, 00:33
Don.
I guess you are about to write a book on the VIICs. On the various threads there are a lot of information which could be organized, the problem is to evaluate which info's are the right as many are assumptions.
 The WW2 story of U 995 is a story of an average Uboots operation in the Artic, focusing on the allied convoys to Murmansk. A norwegian has written a book of 97 pages on the subject concentrating on U 995, but included  parts of the other VIICs and one XXIII taken over by the Norwegian Navy.
The book is unfortunately only in norwegian, it contains many interesting details as to the U-boot warfare including  correspondence and interview with Hans Georg Hess, the last CO of U 995, at an age of 21 being the youngest CO of a VIIC ever. He became a lawyer holding a PhD after the war.  He had a meeting with some ex preys ,norwegians convoy gunners,  on board the U 995 September 1992.  I believe he died in 2009. Below a photo of the last German CO of U 995 Hans Georg Hess taken September 1992 on board the museum U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Oct , 2014, 21:10
Hello Mr. Tore,


I updated page 320 to include info about CO Hess and I made a correction that Maciek suggested as well.  I uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Oct , 2014, 00:52
Don.
The story of U-995 did not end by Hans Georg Hess 9 th. mission. She escaped operation Deadlight as she was not seaworthy for the transfer to Scotland because of the unfinished schnorchel conversion.  She was then put away in one of the small fjordbranches of the Trondheimsfjord by the norwegians. 6 th. of December 1952 she was commission as KNM Kaura by the norwegian navy. I became her chief engineer May 1953, and stayed on board during her period as front line submarine til 1955, when she got a major maintenance and conversion. After that she became a test and training submarine until she was faced out and sold to Germany for 1,- Dmark as museumsboat. Then towed to Kiel, Germany 1965 and eventually after some difficulties, restored in 1970-71 and handed over during an official sermon in Kiel  Oct. 1971 as a war memorial of the german submariners.
Down below are a few photos from my private collection. The lower is from a typical maneuvering situation at the switchboard getting alongside. Apart from the CO at the attackperiscope, I don`t think the photos have been published before.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 09 Oct , 2014, 04:31
Do you have more pictures of her at that time?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Oct , 2014, 07:25
Mark.
Yes I have a few, not all are very interesting. Most of my photos are from our missions above the Artic circle and a few from the Trondheim fjords where our submarine pen and main base was. They are all from KNM Kaura ex. U 995.
A strange photo might be that of a test torpedolaunching. We used a dummy torpedo which did not start and just tested the launching system in harbour. A few of the photos I have published before but most of them are never published before .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Oct , 2014, 10:12
Hello Mr. Tore,


Great! and the very first photo of the helmsman shows him looking at the Gyro-repeater.  Now U-995 does NOT look to have any of these instruments.  I was emailing Maciek about these instruments yesterday.  Thank you for the photos...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 09 Oct , 2014, 10:18
I've seen pictures of the Wandtochterkompass in U995 before. Guess they removed it some years ago.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Oct , 2014, 22:17
Hello Mr. Tore,


I added your photo of the Helmsman on page 300 and uploaded the latest version of Skizzenbuch to dropbox.  It getting very close to being finished once I iron out my problems with the speed controller with Maciek's help.  I updated the speed controller again and we'll see... 


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Oct , 2014, 00:09
Don.
Before you finish the Skizzenbuch, I believe there at least two systems worth while to consider, the hydraulics which include both periscopes operations and the schnorchel, and then  the rudder and hydroplane operation including the emergency mechanical hand operation with clutches. Particularly the hydraulic system have a few intricate details, but both are of course vital to a submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Oct , 2014, 11:49
Hello Mr. Tore,


I will start looking into the hydraulics and the control for the rudders and hydroplanes...  I believe the rudders and hydroplanes will be fairly easy to do, but I need to do a little research on the hydraulics...  Thanks for your suggestion.


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 11 Oct , 2014, 12:29
I still don't understand it - what exactly is the Skizzenbuch?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 11 Oct , 2014, 12:33
Hi Mark


Direct translation is sketch book, however Don's book is a bit more than what most people think of as a sketch book,


Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 11 Oct , 2014, 12:42
Hi Jon,


I'm german, the translation was not the problem  ;)  What I mean is what is the plan for this book?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Oct , 2014, 14:57
Mark.
I am not sure I know Dons plans, but he explained once the reason for making a skizzenbuch was to have a good understanding of the various systemsketches which in some cases was confusing to him. I guess as time went he seems to end up with a book which is a bit more elaborate than an ordinary Skizzenbuch in the German understanding  and hence the name Skizzenbuch could be a bit misleading .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Oct , 2014, 23:17
Hello Mr. Tore,


Since the original Skizzenbuck came from the factory for each boat and covered everything mechanical (34 plates just drawings no information).  I decided to explain the functionality of the content of the plates, and then fill in the other areas as well.  I guess I wanted a book that covered most of the basic systems in the type VIIC U-Boat.  I have about 50 books in my library and they contain about 10% of the information I have in Skizzenbuch. 


Now that I am working on the rudders and hydroplanes, I got to a point where something seems strange...  The BBC controller for the rudder is located on the control room forward bulkhead starboard side, and that makes sense.  If they want to go to port the helmsman pushes down on the left (port) button or plunger (he is facing forward).


The hydroplane operators sit in back of the helmsman and work at the BBC controllers mounted on the starboard wall area.  Here is where I get confused; the gauge towards the bulkhead has readings of 25 to 0 to 35 degrees and the other gauge for the crewman in the direction of the stern, his gauge reads 30 to 0 to 30 degrees.


The stern hydroplane has a range of 25 up to 0 to 35 down degrees.  So it looks like the stern hydroplane operator was sitting forward towards the bow???  That doesn't make sense because that would mean the hydroplane mechanical controls would have to cross each other to control the proper hydroplane.  Is that the way it was actually designed?  Or, If during the restoration the museum people swapped the Hydroplane gauges?


Please advise...


Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2014, 10:16
Hello Mr. Tore,


I believe the U-Boat Museum got the gauges swapped...  See the photo from U-570 attached  Is there a clutch lever to engage/disengage the hydroplane manual hand-wheel.  I don't believe they want the hand-wheel rotating while using the push buttons on the hydroplane controller.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2014, 12:54
Don.
I don`t think the fwd hydroplane indicator is swapped with the aft as the dial is clearly marked Vord. Tiefenruder translated forw. hydroplane.  Further the dial for the mechanical indicator (aluminum disc) goes up to 30 degrees see my photo.
If you look careful at the indicator dial it looks as if it has been erased from half of the 25 degrees markings. On some controlroom photos of the rpm repeater for stb engine (propeller) you can see some of the figures are flaking off. I believe the hydroplane indicator is the right one but the dial might have a textdamage.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2014, 18:38
Hello Mr. Tore,


I took a very close look at the bow and stern gauges and disks on U-995


The bow gauge has a range of 25 - 0 - 35, and the disk range is 30 - 0 - 40


The stern gauge has a range of 30 - 0 - 30, and the disk range is 35 - 0 - (35) (possibly -can't see it)


It looks like the gauges agree with the disks,  I believe that a manual control could get a greater degree of angle like the manual states for the rudder (33 vs 35 when manually driven).


I have come to the conclusion that the manual would be correct for most Type VIIC U-Boats, and U-996's configuration is correct as well.  The manual covers VII's built by 19.9.40.  U-995 a type VIIV/42 and was commissioned on 19.9.43, so what changed?  All the data seems to match up between the VIIC and the VIIC/42 and there seems to be no difference in length, bean, weight, etc,... 


Could the Atlantic Bow have caused a redesign change in the dive plane angles?  Did the VIIC/41 or any later VIIC with the Atlantic bow require a greater forward dive angle to get the wider bow to submerge, and match the Type VIIC dive characteristics with the narrower bow?


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2014, 21:14
Hello again Mr. Tore,


I believe you talked about clutches for the hydroplane manual controls.  I don't believe they would want the hand-wheels moving when operating electrically,  Where are they located?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2014, 00:50
Don.
I am afraid I am a bit uncertain on the hydroplane angles. The overall length of the Uboats having the Atlantic bow is about 280 mm longer than the conventional VIIC  bow. According to Simon it is in addition raised gradually 150 mm from frame 104. This alone is not much for changing the design angle of the hydroplanes. However it could be that the flare of the Atlantic bow could influence the reaction time of the boat due to resistance which again could be compensated by different angle relations in some cases. I have not seen any publication or discussion on this subject, so I have to emphasise it is only an assumption.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2014, 02:15
Don.
The air operated clutches for the hydroplanes are situated locally at the hydroplane gear disengaging the electric drive and engaging the mechanical drive. The operation is controlled from the controlroom, I assume the clutching valves are situated as marked on my image below close to the hydroplaneoperators. As far as I remember the electric and the mechanical hydroplane indicators are operating in both configurations.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Oct , 2014, 19:42
Hello Mr. Tore,


I completed the section on Rudders and Hydroplanes in Skizzenbuch on pages 168 - 173 and uploaded the latest versuon to dropbox...  Now to look at the hydraulic source for the Schnorchel.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Oct , 2014, 21:56
Hello again Mr. Tore,


Figuring out the Hydraulic plate was not a problem (I Think!)...  I will attach my understanding of it.  However, I know where most of the schnorchel components are located, but the general hydraulic components are questionable?  I believe on the hydraulic plate the two main pumps are electrically driven and the other 3 (two in the tower for training and raising/lowering the attack periscope, and one in the control room for the aerial periscope raising/lowering are oil pressure driven pumps.


I don't know the location of the 2 electrical driven main pumps, the 93 gallon oil reservoir tank, and the 3 31 gallon HP oil tanks, and most importantly where the schnorchel taps into the HP oil and Return oil.  It looks like it all may all be in the cabinet area where the schnorchel control valve is located, except for those 4 tanks...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Oct , 2014, 07:09
Don.
I guess the easiest way is I give an explanation of the system.
The hydraulic system is operating the two periscopes and the schnorchel. It consist of two IMO type screw pressurepumps, one as auxiliary, taking hydraulic oil from a system tank and controlled by micro pressureswitches within a pressurerange govern by the oil level in the system tank. The oil is supplied to three aircushioned accumulators having each a capacity of 118 liters and a pressure working range between 48 to 84 bar. All situated in the controlroom between the attack periscopecasing and  stb. pressurehull. The system is adjusted by filling the accumulators with air  at 10 bar. where upon oil is pumped into the accumulators up to the lowest level testpipe,and the air is admitted to 48 bar being the lowest pressurelevel where the pump has to start.The  accumulators are then filled with oil until the pressure is 84 bar being the max. pressure where the pressure switch is adjusted to stop the pump. The unusual with this system is that the pressure switches are controlled by the static level pressure in the system tank rather than the pressure in the accumulators.
From the accumulators the oil is delivered to a oil slide, after a branch off with stopvalve to the schnorchel, which is controlling the operation of an IMO type screwmotor ( converter) engaging the drivespindle via worm geardrive to both  winches for raising and lowering the periscopes by wire. The IMO type converter is a screwpump able to run as motor (converter) when pressureoil is supplied and the direction of rotation is determined by which inlet the oil is supplied. The oil intake is controlled by the controlslide, see drawing, which again is controlled by the raising/lowering periscope handle. On the sketch, red are the pressurelines, purple are the return. When the handle is pushed down (lowering periscope) the slide admits pressureoil to the endstopper (which is preventing the periscope to exceed the adjusted travel). The endstopper consist of a rod driven by the periscopewinch and having a threaded end engaging internal threads in a sleeve inside the endstopper casing. As the winch rotates the rod, the sleeve travels back and forth between the travel ends and the slide opens for oilsupply and return to the operating slide of the IMO converter moving same up or down allowing pressure and returnoil to the selected inlet/outlet ( selected rotation direction). At the end of the periscope travel the sleeve shut  the supply and open to return on both ends of the slide which is the pushed by the balancing springs on both ends of the slide to a shut position and the periscope stops regardless pushing the periscopehandle beyond the limit.
The attack periscope has a different raise/lower handle but the working is the same. However an additional handle is provided next to the depthgauge. This handle can be switch in by a selectorslide, see drawing. The purpose for this arrangement is to have a man accurately controlling the periscope height above the surface. The attack periscope has a direct footcontrol of the controlslide, skipping  a foothandle, for turning the periscope.
The schnorchel hydraulic system takes its supply and return from the direct supply/returnlines as can be seen on the sketch, then further to the raise and lower handle via hullvalves to the schnorchel cylinder in the casing outside the pressurehull as previously discussed.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Oct , 2014, 11:32
Hello Mr. Tore,


WOW!!!  I am so impressed with your knowledge of the technical details of this U-Boat.  Sir, you continue to amaze me!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Oct , 2014, 22:35
Hello Mr. Tore'


I updated Skizzenbuch with the latest info and uploaded it to dropbox...


Hydraulic Periscope   pages 213 - 219
Schnorchel  Pages 324 - 331


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2014, 01:14
Don.
I had a brief look into your latest Skizzenbook and have a few remarks which I shall revert to a bit later, however right now I shall just mention the hand operation of the hydroplanes.
May be you should include a description of the rather elaborate yet simple mechanical system consisting of rods, stuffingboxes, bearings with grease nipples and bevelgears going from the controlroom to the fwd. and aft torpedorooms ending at the gearboxes with clutches to the hydroplanes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Oct , 2014, 01:22
Hi Gentlemen,

here are some additions to Tore's excellent explanations.

The air operated clutches for the hydroplanes are situated locally at the hydroplane gear disengaging the electric drive and engaging the mechanical drive. The operation is controlled from the controlroom, I assume the clutching valves are situated as marked on my image below close to the hydroplaneoperators. As far as I remember the electric and the mechanical hydroplane indicators are operating in both configurations.

The valves controlling pneumatic clutches were marked by Tore correctly. As Tore said, electric and mechanical angle indicators were operating in both configurations (mechanical indicators were moved by means of flexible wire - so called Teleflex system, the electrical indicators were DC systems, utilizing the voltage divider principle).

The clutches were located near the electric motors - the forward motor with the clutch is invisible (under the bow torpedo room floor, in the bilge, between lower torpedo tubes), but you can clearly see the aft motor with the gear and clutch (with the compressed air line connected). There should be noted, that the clutches were engaged remotely from the control room (by means of control valves), but to disengage them, the crew man had to be sent to the clutch and he had to disengage it manually (by means of the handle).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Oct , 2014, 02:07
Some comments to the hydraulic system.
On the first photo you can see the control room of HMS Graph (ex-U570) - you can see, that some parts of hydraulic installations related to Schnorchel are missing (or to be more specific - in the control room of U995 there are some additional elements :) )
I have also attached the drawing, which presents the periscope winch wires.
On the second photo, I have marked the particular elements of the control room periscope winch. The markings are as follows:
1. Periscope lowering/rising "pilot" valve ("Fahrschalter" on the German drawing)
2. The periscope winch drum
3. Hydraulic motor driving the periscope winch/drum
4. The "control" valve" ("Steuerschieber" on German drawing)
5. The shaft for manual rising/lowering the periscope
6. The pulleys for the wires  rising the periscope
7. The guide for the wire lowering the periscope

I have also attached one more drawing, presenting pilot and control valves as well as limit-valve and hydraulic motor.

Finally, on the turm07.jpg photo you can see the winch for the attack periscope in the conning tower, together with the hydraulic  motor and control valve and the shaft for the manual drive.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2014, 08:51
Don.
Maciek has published some excellent drawings which I have never seen and I have included his photo of the IMO type converter with lower/raising slide and endstopper which gives a better image of the component. The IMO converter I included as I did not have the German drawings, is a double scewtype for balancing the axial forces on the screw, whereas the German type of converter is a single screw type which means you have to balance the axial forces hydraulically. On the very good cross section drawing of the converter shared by Maciek you can clearly see the balancing bore in the casing going to the balancing piston at the end of the screw. Thank you Maciek for sharing these drawings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2014, 09:47
Don .
Macieks pictures of the dogclutches for the hydroplanes gives a good impression how they work. I have made some colour on the components to explain the working. The yellow parts are the parts moving when the electric motors are connected, the normal configuration. On this shaft are two sleeves having rims with outside teeth and a bore with axial four grooves. The sleeves can be moved axially on the yellow shaft having four axial keys matching the inside grooves of the sleeve bore. In normal service the emotor is engaged by moving the left sleeve into the e motor wormdrive wheel which have a bore with rollerbearings on the hyroplane shaft and a bore with internal teeth matching the outer teeth of the left sleeve. As the sleeve is locked to the yellow shaft by the four keys and connected to the e motor by the worm gear, the e motor is the operating the hydroplanes. At the same time the other sleeve to the right is disengaged from a similar unit on the right side and the manual operation is disengaged, the manual operation sleeve is rotating free on the yellow  shaft which is supported in a rollerbearing inside the coupling flanges of the manual driveshaft. When air is admitted to the pneumatic cylinder from the controlroom two forks engaging both sleeves via sleevegrooves and moves both sleeves to the right thereby disengaging the motor wormgearwheel and engaging the internal teeth of the manual drive shaft which then is in operation. The yellow shaft is rotating freely on the roller bearing in the wormgearwheel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2014, 10:04
Hello Mr. Tore or Maciek,


On the hydroplane clutch casing where the pressure vessel is located there looks to be a pressure release cap or valve.  Is this to relieve the pressure so the disengage lever cam move back to motor control?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2014, 10:57
Don.
May be you are referring to the springloaded catch?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2014, 12:40

Hello Mr. Tore,

Oh, I see...  It's sort of like a buffer.  Restricted air in and out???

Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2014, 13:08
Don.
It is a springloaded locking pin which rest in the rodgroves keeping the rod and couplingsleeves in the two positions, electric or hand drive. As Maciek says the pneumatic piston controlled from the controlroom works only one way, disengaging the the electric drive /engaging the handoperation by admitting air to one side of the piston (green), the other way has to be set locally by hand thus no airconnection on the other side only venting bore ( blue).  The lockingpin snaps in either of the two rodgrooves by the spring.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2014, 21:00

Hello Mr. Tore,


I have a problem understanding the working of the end stopper used in the periscope wench raising or lowering.  If we use the detailed drawing provided by Maciek here is what I see...[size=78%]…  [/size]


The internal threads and the shaft look to have the possibility of just a few terns, and then the internal sleeve will come in contact with the top or the bottom of the end stopper casing depending on the drive shaft direction of rotation.  So, it looks like the periscope will not move very far before the end stopper comes to a stopping point and the shaft cannot rotate any more.


The aerial periscope eyepiece is normally in a well and below the control room floor.  Therefore, there is a fairly long distance to move up to be at eye level when standing on the control room floor.  The only thing I can figure is the gearing ratio is such that the bottom of the end stopper represents the bottom of the well and the top of the end stopper represents the maximum height the periscope can be raised.


The end stopper details of the channels on the sides of the sleeve are mostly blacked out.  Do you have a drawing with those details?  I can guess, but I don't like to do that!


As usual. I'm lost in the technical details...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2014, 22:37
I'll guess anyway...


Perhaps this?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Oct , 2014, 01:06
Don.
The endstopper controlshaft is driven by a  system from the IMO converter having rotating pto from the drive spindle via a worm gear, with ratio, engaging a gearwheel, with ratio, all reducing the rotating movement which is then transmitted to the endstopper via a chaingear, again a possible rotation reduction. I don't have a drawing of the system, but I post a sketch of the system below. As you see, apart from the internal threads in the endstopper slide there are several reduction elements in relation to the periscopetravel. As it is only an end stopper and not an indicator it does not need to have a big movement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2014, 09:43
Don.
Your Skizzenbuch.
On page 168 you are stating: However the U-boats does take on the dynamic diver characteristics when it surfaces with the ballast tanks flooded and used dieselexhaust to blow the ballast. To remain surfaced at that time, diesel power and diveplane upward angle is used.
I am afraid it is a bit different. Normally the VIICs are surfaced by taking the boat up to periscope depth by e-motors and hydroplanes, the ballast tanks are still filled with water and you have normal neutral buoyancy. Then the CO takes a periscope sweep and if everything is OK he  gives the order surface and  the ballasttanks are blown by compressed air. You don`t surface the boat by hydroplanes. At a given point in surfacing the boats metacentric height is reduced and the boat becomes a bit unstable. Depending upon the sea and the submarines relative position the CO evaluate the situation before he orders stop blowing. The reason for this procedure is that you don`t want to be hit by a major wave sideways when you are in an unstable condition hence the degree of airblowing (surfacing) is determined by the circumstances mentioned. When the submarine has semi surfaced to the wishes of the CO, he enters the bridge and if everything is OK he gives the order to start the diesel and blow the residue ballast water by exhaust. The use of diesel exhaust to blow the ballast tanks is to save HP air. You may start the other diesel for propulsion to keep the submarine up against the sea.
Circumstances in wartime might require deviation from the above procedures.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 18 Oct , 2014, 10:27
Hi Tore


Just to change to subject slightly, external torpedo storage containers, did any of the Norwegian boats still have them?, were they used at all?, if either, did they have a pressure line going to them or were they just a waterproof container?


Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2014, 11:58
Jon.
I believe they were removed on all the boats as well as some of the casing deck containers.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 18 Oct , 2014, 14:15
Hi Tore,


Thanks for the reply


Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Oct , 2014, 18:19
Hello Mr. Tore and Maciek,


1.  I added two pages 160 -161 with photos & info about the exhaust blowing manifold valves per Maciek.
2.  I deleted some info about surfacing per Mr. Tore and added info on page 163
3.  I added corrected info about rudders and hydroplanes 170 - 177
4.  I added corrected info periscope hydraulic drive on pages 217 - 225
5.  The schnorchel section is at pages 330 - 337 (I believe it has been checked out?)


Skizzenbuch has grown to 349 pages, so I had to renumber the pages in my 3 Word documents and re-merge them into a single PDF file.  Sections have different page numbers every time I make additions and the additions have to be two pages so the Plates end up on the right side of the book and on an odd page number..


However, I welcome any suggestions or corrections because I what to get Skizzenbuch right!  I have loaded the latest version of Skizzenbuch into dropbox...  :)


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Oct , 2014, 20:35
Hello Mr. Tore,


The ratchet and anti-backup pawl looks to give the crewman the possibility of raising the periscopes manually.  However, I do believe the drive shaft must be disengaged during a normal hydraulic wench operation.  How is this done?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2014, 14:40
Don.
I have looked briefly through you Skizzenbuch (13) edition and have a few remarks related to the exhaustblowing of ballasttanks. As you might have noticed, the HP air hullvalves for blowing the ballasttanks have a non return valve  or check valve as you would say, integrated. The exhaustblowing valves have not, and that calls for some care, otherwise the ballasttanks might be vented through the exhaust system. Thus when you start exhaustblowing you first start the diesel the conventional way by having the inner and outer exhaust flapvalve fully open, then you adjust the pressure to 0,5 bar before you open the main exhaustvalve to the distributionpanel operated from the controlroom. Just to be sure no venting shall occur.
As the internal pressure varies in the different tanks f.i. MBT3 require a higher pressure than the saddle tanks, you blow the tanks separately otherwise the exhaust, taking the flow where you have the least resistance, shall escape. Thus the exhaustblowing is a timeconsuming affair. By the HP airblowing you don`t get the same problem of escaping air, as you normally don't empty the tanks fully  allthough you might have more residue water in the tank having the highest resistance.
I`ll look into the other questions later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Oct , 2014, 21:05
Hello Mr. Tore,


Previously we said the blowing pressure was 1.5 atm which would be equal to 1.5 bar.  Is it OK to use 1.5 bar?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2014, 00:11
Don.
Yes, when the VIICs were at their top the German pressurenominations were  ata which means atmospheres absolute and atu which means atmospheres over. Bar is still used by my generation, but is not correct, barg is more precise meaning atmospheres gauge.  The manometers on a VIIC  usually have a scale starting at 0 meaning the atmospheric pressure. The problem is that the prevailing pressure in the confined space of a VIIC was seldom one atmosphere, usually over or when schnorcheling under. You should compensate for that by having differential pressuregauges as we have discussed before. However in the mannor of speaking amongst the crew talking about pressure, we always meant pressure above atmospheric and 0.5 bar is actually 1,5 bar absolute. The time correct nomination for the VIIC pressures would be exhaustpressure should be adjusted to 0,5 atu or 1,5 ata.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Oct , 2014, 07:45
Hi Gentlemen,

I have few words related with the hydraulic system and the diving planes.

Although most of type VII U-Boats were equipped with the diving planes driven by electric motors (as thoroughly discussed above), there were two boats, which were fitted with the hydraulic drive of the diving planes for experimental purposes. These boats were U 206 and U 207. I have no details about experiences related with this drive, but one can suppose, that electric motors driving hydroplanes were replaced by the hydraulic motors (the same as for periscope drive) controlled by pilot valves at diving planes control station.
What was the purpose of usage of the hydraulic drive - one main reason would be noise - the hydraulic drive would be quieter than electric drive.

The type XB U-boats (minelayers) were also equipped with the diving planes driven hydraulically.

The concept of the hydraulic drive was elaborated by Germans in the type XXI U-Boat, where not only periscopes were operated hydraulically, but also torpedo tubes muzzle door opening gear, torpedo reload system, forward diving planes retracting gear and finally diving planes and main rudder drive.
There should be noted, that in this case, the diving planes (and main rudder) were driven not by hydraulic motor (and then by worm gear), but directly by hydraulic pistons/actuators.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Oct , 2014, 08:16
Tore,

to continue the topic of the diving planes and hydraulic systems - in the US Navy, the Gato and Balao type submarines were equipped with the diving planes driven hydraulically (by means of the pistons/actuators). I have found no information, what was the British practice - could you present how it was done in British way?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2014, 09:50
Maciek.
Limiting my experience to V, S, T and A class British submarines I would say they used by far more hydraulics than the Germans. Apart from the periscopes,- the hydroplanes , rudders, vents and Kingstons were operated hydraulically even the capstans and windlasses. They had different hydraulic actuators depending upon the movement required and they made use of rams pistons f.i. on the vents required relatively small movements, IMO converters and VSG unites were widely used as well. For the hydraulics used outside the pressure hull the oleo systems were used. The oleo system is converting the energy transmission fluid from f.i. hydraulic oil to glycerin omitting the risk of oilslick in case of leakages. When you operated a British submarine you got the impression of a very modern vessel whereas the VIIC was a sturdy oldfashioned full of mechanical rods and gear vessel. Yet the VIIC gave a good feeling as you had direct mechanical contact with the elements you operated.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2014, 11:39
Hello Mr. Tore,


If we connected a pressure gauge that reads 0.0 bar based on the internal hull pressure as a reference, then the blowing pressure read on the pressure gauge for the blowing manifold would be 0.5 bar?   The absolute pressure would be 0.5 bar, plus 1 bar for the atmosphereic pressure, or 1.5 bar?  That seems confusing...  I would think that the exhaust pressure should be expressed as what is measurable with a pressure gauge.


My question is what pressure does the engine crewman adjust the blowing pressure to when viewing his pressure gauge?  0.5 bar...  Is this the gauge ? (see attachment)


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2014, 14:27
Don.
 In the jungle of pressure definitions it is easy to get confused. The way we used the pressuregauges was generally the figures at 0 was atmospheric pressures anything below was vacuum above was pressure. So when blowing the ballasttanks by exhaust at 0.5 at. it meant 0.5 at above the atmospheric pressure. If you were using like 0,5 at absolute you would have been venting the tanks. What sometimes could be a problem was that the overpressure in the boat could be excessive and the manometersan  would show  a higher pressure  as the 0 point could be at 0.1 or 0.2 at. When exhaustblowing this would not occur. The gauge you show could very well be the exhaustback pressure gauge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2014, 20:53
Hello Mr. Tore,


As far as exhaust pressure blowing goes, I believe I will stick with the pressure that is seen on the pressure gauge (0.5 atu = 0.5 bar)...

I was thinking (very dangerous sometime), but I never seen any indication as to the location of the hydraulic oil supply tank (over 350 Gallons).  It looks like a suitable space for that large tank would be under the helmsman and plainsmen seat???  am I close?


Regards,
Don_




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2014, 21:39
Hello Mr. Tore,


One other question...  the "Fahrtmeßanlage" speed measuring system has a dial that indicates 0 - 20 Knots.  Was it sophisticated enough to take into account for the influence of the ocean current (+ or - knots)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2014, 23:29
Hello Mr. Tore and Maciek,


I updated Skizzenbuch with added pages 204, 205 on the oxygen system with info from Maciek, and the latest version was uploaded to dropbox (modified date Oct-21-2014)...


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2014, 00:39
I was thinking (very dangerous sometime), but I never seen any indication as to the location of the hydraulic oil supply tank (over 350 Gallons).  It looks like a suitable space for that large tank would be under the helmsman and plainsmen seat???  am I close?

Under the plainsmen and helmsman seat is something like tool cabinet. The hydraulic oil supply tank is located behind the compressed air manifolds. I have attached drawing with its location marked. I have also attached photo with good view of the one hydraulic pump with driving motor. There are also visible pipe leading from the pump to the accumulators and pipe leading from the collecting tank (with large valve).

One other question...  the "Fahrtmeßanlage" speed measuring system has a dial that indicates 0 - 20 Knots.  Was it sophisticated enough to take into account for the influence of the ocean current (+ or - knots)?

No, the log operating on the principle of the Pitot tube measures speed relative to the surrounding water only.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2014, 01:16
Tore, thank you for your answer.

When you operated a British submarine you got the impression of a very modern vessel whereas the VIIC was a sturdy oldfashioned full of mechanical rods and gear vessel. Yet the VIIC gave a good feeling as you had direct mechanical contact with the elements you operated.

I wonder about diving planes. They are quite crucial elements - if they are damaged (i.e. disconnected from the driving gear) or jammed (especially in "dive" position), they can easily  cause the depth excursion incident. That's why, they are equipped with some backup system - as well driving gear (manual drive) as the mechanical position indicators (apart from electric ones). I wonder, why the German designers decided to use remote mechanical drive from the control room. It would be much safer to provide emergency steering stations locally - in the forward and aft torpedo room respectively (as in the case of the main rudder). I can imagine - that due to depth charges explosions - there are some damages to the relatively long driving shaft lines possible.

As the some kind of interesting fact I can say, that larger U-Boats (type IX and XIV) were equipped with some kind of coupling gear - the both hand-wheels on the plainsmen station could be coupled together to control aft or forward diving planes from both stations - I believe, it could be used, when aft or forward diving planes were operated so hard (due to damages), that one man could not stand it. In such situation, there was additional (third) electric console provided, which was operated by another crew member, who controlled the remaining (undamaged) diving plains pair.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2014, 02:25
Don.
The log system is explained very good by Maciek, I can only add the Pitot system is based on a static and dynamic pressure, the dynamic nozzles (two) are place on port and stb bow and the static nozzles are I believe at the forward end of MBT 3.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2014, 02:29
Don.
I have made a sketch showing the various hydraulic supply components place in the control room. Note the hydraulic tank capacity is 345 liters not gallons.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Oct , 2014, 02:51
Hi Gents,

The log system is explained very good by Maciek, I can only add the Pitot system is based on a static and dynamic pressure, the dynamic nozzles (two) are place on port and stb bow and the static nozzles are I believe at the forward end of MBT 3.

I have attached photos of the dynamic nozzles on the bow.

Note the hydraulic tank capacity is 345 liters not gallons.

I estimate its size on approximately 110 cm length, 75 cm width and 40 cm height.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2014, 06:39
Maciek.
I believe the mechanical emergency operation of the hydroplanes was very sturdy and placed inside the pressurehull could take a lot of beating from depthcharging. However the system required a lot of maintenance (greasing) to stay relyable. A local 3 positions for operations of rudder and hydroplanes would be a challenge for the immediate communication and would require further instruments for immediate response to keep the vessels  positions (angle) which is a combination of operation of fwd. and aft hydroplanes. I guess I would have preferred to maintain the system of a VIIC above three local emergency operations.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Oct , 2014, 20:16
Hello Mr. Tore and Maciek,


Thank you for the information about the location of the hydraulic system tank and the speed measuring system...  I updated Skizzenbuch and added the Hydraulic system tank location in the hydraulics section, and the speed measuring system with the rudders and hydroplanes.  The latest version of Skizzenbuch was uploaded to dropbox...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2014, 00:46
Don.
I have checked your latest additions to your Skizzenbuch and it looks OK to me. A minor comment which has nothing to do with the understanding of the system. I just accidentally stumbled over your remark in connection with the valve assembly on page 225 :" ... the valves were called a christmas tree because of the multicoloured handwheels." I have previously on this thread warned against making conclusions based on the present state of the museums U 995. The vigorous use of multi coloured items has nothing do with the original.  Today all the red paintings makes the impression that poor old U-995 got the measles.
We did not use the christmas tree expression 60- 70 years ago in Europe, I guess it came from US oil exploration and was used in the beginning as a slang for the cluster of valves on the top  of the drilling hole containing the blow out preventer. The expression reflects rather to the shape of the valve cluster having many branches and not colours as the assembly was not coloured. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Oct , 2014, 02:08
Hi Tore,

I believe the mechanical emergency operation of the hydroplanes was very sturdy and placed inside the pressurehull could take a lot of beating from depthcharging. However the system required a lot of maintenance (greasing) to stay relyable. A local 3 positions for operations of rudder and hydroplanes would be a challenge for the immediate communication and would require further instruments for immediate response to keep the vessels  positions (angle) which is a combination of operation of fwd. and aft hydroplanes. I guess I would have preferred to maintain the system of a VIIC above three local emergency operations.

Thank you for your answer. Of course, emergency steering stations located locally in aft and forward torpedo rooms would be quite challenging.

Anyway, US Gato and Balao diving planes systems were operated hydraulically. The description can be found here:
http://www.maritime.org/doc/fleetsub/hydr/chap5.htm#5A (http://www.maritime.org/doc/fleetsub/hydr/chap5.htm#5A)
As I understand, there is no other way of controlling them than hydraulic. In case of failure of the hydraulic pumps, the only emergency recovery mode is the hand pump. It seems, that in case of damaging the hydraulic piping, the whole system is broken.

On the other hand, the hydraulically driven diving planes on type XXI U-Boats were fitted with emergency hand drive (but only aft pair).
I suppose, that it is because the aft plains have more effect on the control of the submarine than forward planes.

Here is another example - the British Oberon class submarine:
http://maritime.org/doc/oberon/hydraulics/index.htm#pg26 (http://maritime.org/doc/oberon/hydraulics/index.htm#pg26)

These subs have also hydraulically operated diving planes, and it seems, that after pair has the following emergency gear - in case of damage of the hydraulic system, to the actuating piston controlling the planes can be connected high pressure air, which controls the angle of planes (or sets them to the "surface" position).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2014, 06:42
Maciek.
Interesting  information on the British "O" class which at my time was very hush,hush, allthough we had a naval architect reading a paper on the development of the class. Further it gives a documentation of the extensive use of hydraulics of the British submarines compaired to the Germans. Visually an obvious difference between the British ( and US) and the German submarines during WW2 was the forward hydroplanes. The British and US submarines had the hydroplanes well above the surfaced waterline and the Germans well below. There were many pros and cons to both systems. The German having an immediate quick active effect on the diving, the British needed to be folded out and was not active before the bow was submerged. The British was easier to manoeuvre in harbour but had an extra element (folding). The German could have a problem with dropping the anchor and the anchor cable, I have personally experienced the anchor cable being stuck between the hydroplane and guard ( deflector), but the hydroplanes could act as a stabilizing instrument cruising surfaced in rough sea. To a certain extent a similar system is used as stabilizers on large passenger vessels today. I post a photo never published before showing me jumping into the sea in shallow water divingsuit close to the forward folded hydroplane of a British T class submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Oct , 2014, 12:14
Hello Mr. Tore,


I have a question about page 164 the second paragraph... It states the compression for blowing the ballast tanks is 1.5 atm (I believe that would be 0.5 atm plus 1.0 atmosphere external pressure  that equals 1.5 atm absolute).


Since you don't specify absolute pressure, would it be wrong to substitute 0.5 atm or atu as read on the pressure gauge in the paragraph just to be consistant?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2014, 15:05
Don.
May be we should refer to your photo of the exhaust manometer in the engine room starting at 0 being the atmospheric pressure, which is app. 10 meter watercolumn fresh water at 4 degrees C. Let us assume the submarine has been surfaced by HP air up to the top of the saddle tanks and that the salinity and temp. makes the seawater specific gravity like the freshwater (not 100% correct). That means we start blowing the saddletanks at a counterpressure of 0.22 mwc,  the counter pressure shall gradually be reduced as the boat raise. If you start exhaustblowing at MBT 3 you shall have a counterpressure of almost 5 mwc which means almost no water is forced out of the tank hence we blow that tank later. MBT 1 and 5 have less counter pressure than MBT 3 so we blow those tanks before 3 as the boat rise further. If we take all at the same time  only the saddletanks are blown the exhaust disappear via the saddletanks Kingstons.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Oct , 2014, 20:55
Hello Mr. Tore,


Thanks for the info and drawing....  I got the drawing and info in by changing some wording and moved things around, but all in pages 164 through 166.  The latest Skizzenbuch was uploaded to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2014, 02:22
Don.
 I checked your last Skizzenbook (2) on the exhaust blowing which is OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Oct , 2014, 12:35
Don.
On page 59 in your Skizzenbuch you have two photographs U 570 and U 995 to show two different fuel sample collectors. I am not sure if you have noticed an even more interesting difference on U 570 being commissioned 1941 there is no wheel for venting the bow buoyancy tank whereas U 995 being commissioned 1943 you have the ventwheel next to the ventwheel of MBT 5, in the controlroom see my picture. The explanation you`ll find on plate 28, the earlier version of VIICs had a local venting wheel in the forward torpedoroom as shown on my picture.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Oct , 2014, 14:37
Hello Mr. Tore,


Interesting...  I have photos from a U-995 CD that shows two large hand-wheels above both the froward and aft pressure hull passage ways and 3 smaller ones above them. I assume one is for dive tank 1, and the others (?).


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 00:25
Don,

I can see only two small hand-wheels above - these are hand-wheels for operating gate-valves of the ventilation ducts (located behind the bulkhead).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2014, 00:32
Don.
May be you remember the residue venting of aft MBT 2 being the other ventwheel. So where is the venting wheel of stern buoyancytank? Both version of the VII Cs have local venting of the stern buoyancy tank being a barhandle up front of the steeringgear. See the photo. Otherwise I agree with Maciek the other two wheels are for the ventilation ducts.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 00:37
Tore,

May be you remember the residue venting of aft MBT 2 being the other ventwheel. So where is the venting wheel of stern buoyancytank? Both version of the VII Cs have local venting of the stern buoyancy tank being a barhandle up front of the steeringgear. See the photo. Otherwise I agree with Maciek the other two wheels are for the ventilation ducts.


Isn't this handle (marked as "stern buoyancy tank") of the Junkers compressor exhaust valve grinding gear?

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 00:44
I have attached photos of the gate valves located behind aft control room bulkhead (two red wheels). The green wheel is the valve of the HP air bank 3 - which consists of two air flask located in the Petty Officers' Room.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 01:10
Tore,

the hand wheel for the stern buoyancy tank should be located somewhere between 6th and 7th pressure hull frame - the same as the handle you have indicated.
I have attached close view of this handle - it seems quite strange for the vent valve - I think, it is manual drive for the diesel air-compressor exhaust valve grinding gear.

Anyway, I was not able to identify something else looking like the drive for the vent valve.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 01:45
To make more confusion - here is the photo of the aft torpedo room of the U-570:

(http://uboatarchive.net/U-570Photo31.jpg)

There are also two valves visible - a little different arrangement than on the U-995...

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2014, 02:52
Maciek.
I remember we came to a conclusion that this handle would be the grinding (ratchet) for the Junker. When I was looking for the venting of the stern buoyancy tank I realised it was not operated from the control room and that the local rod for the pressurehull entrance was exactly where the we assumed the Junker grinding shaft was. I forgot about the interlock confusion. I still think it has to be the sternbuoyancy tankventing as there are no other indication for this venting. The confusing element is the interlock, it could be to prevent opening the stern tankventing while the Junker was running. The two stroke opposed freepiston balancing was very susceptible to exhaust backpressure. I`ll ponder a bit and revert.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 03:00
I remember we came to a conclusion that this handle would be the grinding (ratchet) for the Junker. When I was looking for the venting of the stern buoyancy tank I realised it was not operated from the control room and that the local rod for the pressurehull entrance was exactly where the we assumed the Junker grinding shaft was. I forgot about the interlock confusion. I still think it has to be the sternbuoyancy tankventing as there are no other indication for this venting. The confusing element is the interlock, it could be to prevent opening the stern tankventing while the Junker was running. The two stroke opposed freepiston balancing was very susceptible to exhaust backpressure. I`ll ponder a bit and revert.

Tore, it is interesting. I think, you are right.

One note - on your drawing you are referring to the outer shell frames. I have marked (with green color) the pressure hull frames and the location of the valve.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 03:08
From the British report on HMS Graph (ex U-570)

Quote
5.  In the case of the Junker's air compressor exhaust valve, the valve floats on the end of the main spindle.  It is rotated by an extension from the valve passing down the centre of the main spindle and is turned by hand.

I have also searched my archive materials and found following description referring to the Junkers compressor:

Quote
Die Störungen haben zumeist ihre Ursache darin, daß zu viel Schwallwasser in die Abgasleitung des Verdichters eintritt. Um die besonders bei Seegang auftretenden Anlaßschwierigkeiten zu beheben, ist z. Zt. (April 1941) eine Hilfsauspuffleitungen den Raum und auch eine Verbindungsleitung Stufe I Spülluft bei Alle Booten in Aussicht genommen. Bei einem Boot versuchsweise zwischen Abgasein- und austritt ein Wasserfänger eingebaut. Der Verdichter koonte bei geschickter Handhabung bis Seegang 5 angestellt und in Betrieb gehalten werden.

Not all is clear for me, but I would translate it as follows:

Quote
The damages are mostly caused by the fact that too much water enters the exhaust pipe of the compressor. To remove these difficulties encountered especially in rough seas, an auxiliary spaces in the exhaust line were introduced and also introduced the scavenging air line to stage I at all boats. One boat was experimentally fitted with the water-trap between beginning and ending of exhaust piping.The compressor can be skilfully operated up to the  sea state 5.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2014, 09:19
Maciek.
Sorry about my drawing which I made in a hurry mixing the pressurehull framing with the outer hull thanks for correcting and Don don't`make use of my drawing, use Macieks green correction.
The German text indicate that they had trouble with water even entering the Junkers exhaust pipe, it seems they already in 1941 tried to make modifications. Of course the stern buoyancy tank was an important element in keeping the exhaust outlet up to prevent intrusion of water in the exhaustpipe increasing the risk of waterstroke, upsetting the balancing and the two stroke scavenging as well.
 I think we can make certain that the handle is the stern buoyancy tank venting handle converted from a conventional vent wheel to a 90 degrees turning handle with interlock preventing the Junker compressor to start ( exhaust valve to open) unless the stern buoyancy tank vent is shut, thereby keeping the stern up and exhaust pipe free from the seawater. I have made a sketch how I assume the interlock is working below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Oct , 2014, 11:12
Tore, thanks for the drawing. It looks, that this interlock also prevents flooding the stern buoyancy tank while the exhaust valve is opened.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2014, 11:56
Hello Mr. Tore and Maciek,


Wow!  It looks like one dumb question has generated a lot of good information...  By the way, over night while I was sleeping I remembered the large red hand-wheel was for venting the residual water in the saddle tanks (MBT2). 


Before I retired from NCR as a hardware and software support engineer...  If I had a problem that I could not solve during the day, then I would generally figure out the problem while taking a warm shower or while sleeping.  I guess after retirement my U-Boat hobby has replaced my NCR work load; the same thing is happening again.  This stuff is coming to me in the middle of the night again!!!


I guess we just can't stop old habits...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Oct , 2014, 12:34
Don.
It is not the first time we have figured out the working details when you have no access to drawings or further information. In fact when I was on board many detailed drawing were not available, the advantage then was on board you could start crawling around even dismantle items to make sketches for your own skizzenbuch. I wish I had mine from those days today. It is remarkable little details in the manuals available about the exhaustsystem of the Junker and on the poor old U 995 they have made a hull entrance were the piping should be. We have not yet got all the details on the outboard exhaust piping included exhaustvalve which has many parts within the pressure hull, I think I have a vague idea and shall see if I can compose a sketch within some days. In the meantime may be somebody have some drawings or photos which might give us some details. Lets hope Simon is digging himshelf out of the snow and provide us with some info. :)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2014, 16:20
Hello Mr. Tore,


You mean it snows where Simon lives?  Just joking of course...  Can you provide some information as to how they grind the exhaust shutting valve on the Junkers exhaust system?


Do you have any idea as to why they moved the bow buoyancy control to the control room?  There are no open slots in the buoyancy tanks, so as air escapes the water would have to pour in if opened while submerged.  Or, they open the vent to initially pump water into the bow buoyancy tank and then close off the valve.  Then they can use the trim pump to balance the U-Boat while surfaced?  Or, during a periscope attack they want a bow down angle of 1 1/2 degrees; is this how that is accomplished?



Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2014, 09:39
Don.
I don`t know why they move the bow buoyancy tank venting to the controlroom, but I guess it is more convenient to have the controls in the controlroom. The buoyancy tanks have freeflood holes in the bottom, when you open the vents waterflows freely into the tanks while diving. If the vents are open in surface position the buoyancy is gone in rough sea pitching. The tanks are not used for trimming, when ventvalves are shut in surfaced position they simply gives additional buoyancy when the bow or stern goes under the surface when pitching. You can use any tanks for surface trimming but you avoid the use of the ballast tanks. Large, partly filled tanks have a bad effect on the submarine called free surface effect, that's one of the advantages of having watercompensated fueltanks. Bow down angle of 11/2 degrees is usually accomplished by using hydroplanes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Oct , 2014, 16:50
Hello Mr. Tore,


I'm assuming they did not move the blowing valves for the bow or stern buoyancy tanks in their respective torpedo rooms.  Do you have a photo of these blowing valves?


For example, Plate 12 shows LP air is used to blow/force the sea water out of the buoyancy tanks through the open slots in the bottom of the tanks.


At what level of seas was the commander required to abandon the topside watch for the enemy because of concerns for the safety of the crew in bad weather?  An Atlantic hurricane can generate winds way above 100 MPH and really huge waves...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Oct , 2014, 20:24
Hello Mr. Tore,


I updated Skizzenbuch pages 90 and 91 with the info about the stern buoyancy tank lever and the interlock with the Junker exhaust valve..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2014, 05:05
Don.
LP blowing blowing of buoyancy tanks.  I don`t believe this blowing was very much used, in fact I can`t even remember them. Normally during  surfacing you left the vents open and the tanks drained nicely,I should guess in bad weather some COs would like to break the surface with ventvalves shut and then blow the tanks to to speed up the buoyancy effect. Unfortunately I cannot find any photos of the blowing valves.
The people at the bridge took a lot of beating as sometimes the sea could fill the bridge. I have experienced, particularly during the November storms, that we had to shut the conningtower hatch as we got too much water in the controlroom, once we had to navigate surfaced by the periscope and at the end we continued submerged at a depth of 50 meters. Even at that depth you could feel the swell. Thus you could have people at the bridge in quite bad weather conditions not only depending upon the wave hights, but your course  in relation to the direction of the wind and sea as well. Certainly for the Germans during WW2, not having air superiority, it was necessary to have people on the bridge under all circumstances.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Oct , 2014, 05:13
Don.
I checked your Skizzenbuch 3, OK although not yet complete on the Junker.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Oct , 2014, 08:36
Don
Junker outboard exhaustvalve.
I have looked through all my papers and cannot find any detail on the subject so I have to design the valve based on the photos available. Down below is my sketch which is an assumption/ partly shear guesswork.
The valve consist of a tube steelhousing going through the pressurehull ending in an outboard valve which connect the muffler ( sea) and the inlet ports of the Junker opposed piston dieselpart.  The valve has a free rotating valvedisc (red) and stem with a bore for the valve spindle ( yellow) on which the disc is free to rotate.
The other end of the valvespindle (yellow) has a threaded end engaging threads in the valve wheel hub (pink) which is kept in position by a rim disc in the housing. When turning the pink valvewheel the yellow valvespindle moves up and down shutting/opening the valve, the pink valve hub stays in place. As the red valvestem and disc is connected to the yellow spindle they follow the axial movement of the yellow valvespindle. At the other end of the red valve stem is a gearwheel having a hub with inside slots engaging similar slots on the red valve stem, the gearwheel is kept in place by the housing. Thus the valvestem is sliding axially in the gearwheel when the stem is axially moving by the handwheel turning.
 When the valve is shut and the sternbuoyancy tank vent is open, the Junker valve is locked by the interlock (violet) as a small cam keeps the red valvestem down (shut).
If you have to grind the valve, you shut the valve, a small shaft end protrude out of the casing as shown, and a bar is secured by a screw on this shaft and you turn same thereby rotating a worm which is engaged to the gearwheel on the red valvestem. As the gearwheel bore has slots engaging matcing slots in the red valvestem, the valvestem and valve rotates around the yellow valve spindle and you are grinding the discseat against the housing seats. The valve opens towards the seapressure and you cannot open the valve unless the sternbuoyancy tank vent is shut.
An airpipe (green)is connected to the outboard valve housing which makes it possible to blow the exhaustpipe to the sea while the exhaustpipe is shut to the Junker cleaning the exhaustpipe for water prior to opening of the valve.
I should assume it is an additional hull exhaustvalve as usual. PHU!! Confusing? read it once more and look at the sketch ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Oct , 2014, 20:53
Hello Mr. Tore,


I cut a segment from the aft torpedo room showing the Junker's exhaust valve...  Does it look like all three components are very close to the sale horizontal line?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Oct , 2014, 21:38
Hello Mr. Tore and Maciek,


I uploaded the latest version of Skizzenbuch to dropbox.  Page 345 contains info on Group Listening Devices (GHG, Balkon, and KDB), I also added exterior photos of Bold (Note* without the bird crap on the side and the spikes on the upper deck edge of the U-Boat.  I edited the photos!)...


Regards,
Don_  :)



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Oct , 2014, 02:35
Don..
When reading the page 345 I came over the photo of U 995 hanging in the big crane in Kiel at the time being converted into a museumboat page 344. At that point she had a Balkongeraet and your text  on the photo says : " showing KNM Kaura pennant no. 309 (ex. U 995) in its original configuration".
She never had the balkongeraet in my time I guess this was possibly installed at a later stage may be when she was a training/ research boat. Thus in her original configuration she was without the Balkongeraet.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 28 Oct , 2014, 06:00
Hi Gentlemen,

LP blowing blowing of buoyancy tanks.  I don`t believe this blowing was very much used, in fact I can`t even remember them. Normally during  surfacing you left the vents open and the tanks drained nicely,I should guess in bad weather some COs would like to break the surface with ventvalves shut and then blow the tanks to to speed up the buoyancy effect. Unfortunately I cannot find any photos of the blowing valves.

The location of the low pressure compressed air valves for blowing (bow) buoyancy tank also suggests, that blowing was used rarely.
I have attached the photo of the hull blowing valve of bow buoyancy tank - it is located 78th and 79th pressure hull (internal) frame,
over the upper, port torpedo tube - quite inconvenient place for operation.
I have also marked the valves on the aft (port side) bulkhead of the forward torpedo room. There is also one more valve on blowing
line - comparing these two photos, you can see, that it is also inconveniently located.

I was unable to locate the hull valve for blowing the MBT5, but I have attached photo presenting the MTB1 hull valve.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Oct , 2014, 22:23
Hi Maciek.


To make sure I understand the photos...


1. The photo with all the red arrows pointing to LP valves that lead to blowing the bow buoyancy tank.   Which valve would they use to blow the bow buoyancy tank, the hull valve, or the one down stream? Where are these valves in relation to the forward torpedo tubes?


2. The green hand-wheel is HP air and what is its purpose?


3. The photo is of the aft torpedo tube with the hull valve for MBT1 buried so deeply; am I correct?


I would imagine the hull valve for MBT5 is similarly buried in the forward torpedo room section as well. 


OK...  I have the following


1 - MBT1 and MBT5 venting valve hand-wheels in the control room
2 - The hand lever for venting the stern buoyancy tank in the aft torpedo room (VIIC/41)
3 - The hand-wheel for venting the bow buoyancy tank in the control room (VIIC/41)
4 - The info just provided about blowing the bow buoyancy tank in the forward torpedo room


I don't have info/photo of the blowing valve for the stern Buoyancy tank in the aft torpedo room...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2014, 01:34
Don.
I believe the green wheel valve is what Maciek says on his drawing. It acts as a shut off valve with watertrap for airbank 4. See my picture below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 29 Oct , 2014, 02:24
Hi Don,

1. The photo with all the red arrows pointing to LP valves that lead to blowing the bow buoyancy tank.   Which valve would they use to blow the bow buoyancy tank, the hull valve, or the one down stream? Where are these valves in relation to the forward torpedo tubes?

I have marked the location of the hull valve on the drawing.The "down stream" valve is located on the aft bulkhead of the forward torpedo room (port side).
Which one was used? Hard to say, I suppose, that hull valve would be opened (closed only in emergency) and blowing was done by opening the "down stream" valve.

2. The green hand-wheel is HP air and what is its purpose? 

As Tore answered, this is cut-off valve for the HP air bank. Each HP air bank has similar one.
See this post: http://models.rokket.biz/index.php?topic=921.msg16560#msg16560

3. The photo is of the aft torpedo tube with the hull valve for MBT1 buried so deeply; am I correct?

I would imagine the hull valve for MBT5 is similarly buried in the forward torpedo room section as well. 

That's right.

1 - MBT1 and MBT5 venting valve hand-wheels in the control room

That's right.

2 - The hand lever for venting the stern buoyancy tank in the aft torpedo room (VIIC/41)

That's right.

3 - The hand-wheel for venting the bow buoyancy tank in the control room (VIIC/41)

That's right.

4 - The info just provided about blowing the bow buoyancy tank in the forward torpedo room

That's right.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2014, 02:40
Don.
Junker exhaust assumption.
I "redesigned" my idea a bit to match the prevailing photos. To make the system complete I studied the the coolingwater scheme showing the old system which obviously has a seawatercooled hullvalve, a simplified system of the mainengine  hull exhaustvalve. The new shut of valve to the silencer (sea) is outside the pressure hull and could be seawatercooled by the blue pipe on my systemsketch. Otherwise the sketches should be pretty selfexplaining and it only remains to repeat: these sketches are not facts they are assumptions.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2014, 12:37
Hello Mr. Tore,


I have a question about the Bouyancy tanks...


1.  Was the bow buoyancy tank above the waterline?  I remember you saying if the vent were opened that it drained quite nicely...  That would eliminate the need to crawl among the fwd torpedo tubes to get to the hull valve to blow the tank.


2.  The stern buoyancy tank looks to be partially below the water line.  If they want to run the Junkers compressor, did they need to blow the tank to get the stern higher, or just clear the water from the exhaust system?


3.  I don't recall ever seeing a drawing that shows the location of the Junkers muffler and exhaust lines outside the pressure hull.  Do you have anything?


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2014, 14:00
Don.
I don`t have a drawing or even a photo of the exhaust silencer and pipes. But I am pretty sure it is situated at about the same level as the mainengine exhaust pipe and silencer, thus well above the surfaced waterline only the outlet probably below the watersurface. The buoyancytanks are marked on your drawing in the skizzenbuch, see my sketch below and the tanks are as you see above the watersurface having the freefloodgates just below the waterline.
 The problem is not the running of the Junker in calm weather, but in rough sea when the submarine is pitching, then the buoyancy tanks are moving under the surface and above the surface. The amount of water in the tanks increases as the bow or stern dips down in the water and decreases as the tanks are above the surface thus you have a pressure pulsation, a blowing shall not be of any use as air escapes as soon as the freeflood gates get out of the water, but the pitching is reduced by the extra buoyancy when the tanks are submerged as long as the vents are shut. Hence the interlock between the sternbuoyancy  ventvalve and the Junker outboard exhaustvalve. Before starting the Junker you could blow through the pipe and the silencer while the outer exhaustvalve  was shut as indicated on my outer exhaustvalve sketch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2014, 18:53
Hello Mr. Tore,


Thank you for the drawing and information... 


I believe the line of green colored valves in the control room are for blowing the ballast tanks.  I remember you saying the tanks were not fully blown and they used the diesel exhaust to complete the blowing process. 


How do they know when the tanks are at say 70% empty? Do they allow blowing for so many seconds depending upon which tank?  I could see them blowing the tanks completely empty and the pressure gauge beside the distributor would drop to indicate that tank was empty and they were blowing HP air out the tide valves.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2014, 20:59
Hello Mr. Tore,


Sorry about bothering you again...  Plate 12 Shows 2 lines going to the LP blowing distributor: one is a direct line with valves but at 205 atm, and the other one has valves and a pressure reducing valve to 12 atm.


Why the two very different pressure outputs?   The pressure at around 122 meters would be approximately 12 bar.  Normally they are blowing the ballast tanks at periscope depth.  Would using the 205 kg/sq cm that equal to 201 bar ever be needed.  201 bar would be water pressure at 2.049 meters depth; the pressure hull would be completely crushed.  I know this just an exercise with numbers.  However, could the blowing distributor and its tributaries withstand the high pressure and not blow something?  If they blew the saddle tanks at periscope depth with 205 kg/sq cm / 201 atu would there be any damage?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Oct , 2014, 02:03
Don.
The air blowing of the tanks is very much based on experience and watching the gauges and to which extent the CO want to surface on air under the prevailing circumstances. As the ballasttanks have different location in the relation to the surface they have different pressures when emptied. The normal surfacing from periscope depth is checked by the depthgauge and the CO checking the testcock of the top hatch to be sure the hatch above the seawaterlevel before he releases the hatchlocks, having the catch still engaged in view of the overpressure. If the CO want to continue airblowing, the saddletanks are watched and you are able to see air is escaping from the Kingstons. Then you continue with the MBT1 and 5, same procedure, and finally 3. As you see the tanks are blown separately in the last stage. The ideal solution would be to stop blowing the highest tank just a bit before emptied and let the air expansion take the rest when blowing the deepest tank (MBT3) but that takes a lot of experience and normally that part of the blowing is done by exhaust. The primetarget is to save precious HP air and that takes experience.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Oct , 2014, 09:12
Don.
LP air system.
A good remark, but I don`t believe there are two different pressures . The ordinary supply is the automatic reduction valve, the other connection shut. However the other connection is a back up system which has a reduction valve manually controlled, as the symbol for the supplyvalve indicates a manually controlled pressure reduction valve. You`ll find the same system used amongst several others f. inst HP blowing of the main ballasttanks. Having a manually controlled reduction/stopvalve direct connected to the HP system does not mean you are using the full pressure, it is a reductionvalve manually operated to achieve the appropriate pressure which is shown on the relevant manometer. As a safety there are reliefvalves at the end users, set at the max allowable pressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Oct , 2014, 12:22
Hello Mr. Tore,


So, if the U-Boat was sitting on the ocean floor at 200 meters, then the 12 atm blowing pressure would be useless.  At 200 meters the external water pressure would be about 21 atm   However, if they used the manual HP air reducing valve and set the blowing pressure to 25 -30 atm, then they could partially blow the MBT3 to get them off the bottom.  Does this sound logical and doable?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Oct , 2014, 13:51
Don.
When you are blowing the main ballasttanks  you are using the main blowing panel and having direct feeding from the 205 kg/cm2 airbanks. You are using the main blowing valve manually reducing the pressure to what is required up to 25kg/cm2. The main blowing valve has a special sharp valvecone which allows a very accurate pressure  adjustment  shown on the manometer for blowing. The blowing system has reliefvalves for each mainballast tank adjusted to 25 kg/cm2 being the pressure at designed crushing depth( VIIC/41). However the 3.9 m3 air storage  capacity of 205 kg/cm2 is not enough to empty the MBT 1,3 and 5 as you would, according to my calculation, need about 12 m3 of 205 kg/cm2 , at 200 meter you shall need appr 10 m3 of 205 kg/cm2. If you would like to blow only MBT3 incl ducts ( 47,7m3) at 200m you would need according to my calculation 4,65 m3 of 205 kg/cm2.
Thus at these extreme depths it is rather the capacity above the pressure which is the limiting factor. So I guess it is not a good idea to sit on the seabed at 200 meter and try to surface by blowing air.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Oct , 2014, 16:54
Hello Mr. Tore,


I went back and checked with the "Diving Requlation Manual" that Maciek translated...


231 - 239 provides some guidance on settling and breaking loose.



"After lying on the bottom for a long time all bilges are to be pumped into the ballast
tank intended for this. The filling of all bunkers and ballast tanks is to be examined,
and the specific weight of sea water is measured for comparison.



If necessary, continue pumping with the auxiliary drain pump, in order to achieve as gentle a
release from the bottom as possible and to avoid the boat shooting up too quickly.


Blowing with compressed air to release from the bottom must be avoided because of the rising
billow of air. However if blowing can not be avoided, then it must take place in the stern,
because as a result, the boat separates more easily from the bottom than by blowing the center
ballast tanks.
 
After the freeing the boat from the bottom the ballast tanks are to be immediately flooded
again. Blowing the ballast tanks must be carried out carefully, so that inadmissible
pressures in the ballast tanks are avoided, should the flood valves lie in the mud.


239. During release from the bottom the boat is to remain bow down (at least 2°), so that
rudders and screws are not damaged. As soon as the boat is bow down and free forward and aft,
the propellers may be engaged."


So again, I was WRONG!!!  All I had to do was (RTFM) Read The Fine Manual...


Also, the blowing manifold is using HP air to blow the ballast tanks.  It all a matter of the difference in volume between the HP air input pipe diameter; the HP air volume can expand within the ballast tank lower pressure environment, and the water is pushed through the bottom open Kingston/tide valves larger exit area into the sea which provides the blowing resistance according to the depth.



Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2014, 00:48
Don.
As you correctly say  the diving manual deals with being stuck  in the muddy seabottom where you are using momentum to break loose. If we play just with volumes and pressures, Boyle- Mariottes and good old Archimedes laws are the ruling factors.
 If you blow your tanks at large depth say 150 meters, not stuck in the sea bottom and the boat is balanced to neutral buoyancy by the compensating- and trimtanks, and for some reason you want to surface by air, you don`t blow the tanks empty at that depth even if you need MBT 1, 3 and 5 empty to be fully surfaced. You blow carefully with lowest possible pressure and when the boat start to rise stop blowing as you have started a process with gradually less resistance pressure allowing the air in the MBT to expand and pushing the water out through the Kingstons as you rise. If you blow to hard, the tanks empties too quickly and you loose  air through the Kingstons as you rise. In general you would avoid such a surfacing as it is uncontrolled.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Oct , 2014, 12:07
Hello Mr. Tore,



The Safety Valve settings were taken from the U-Boat Type VIIC manual published in 15.7. 40,
and do not reflect changes made to the VIIC/41.  The HP air manifold Safety Valve is set at 205 kg/ sq cm which is approximately 201.03 Bar, and the ballast tank blowing manifold air Safety Valve is set at 30 kg/sq cm (29.42 Bar).


Note, I would think the blowing air would be adjusted to 25 Bar/ ATU since all the gauges were in ATUs? That would put the blowing pressure below the safety valve setting.


Do you know is the Blowing distributor for the VIIC/41 had a different Safety Valve with a higher setting to allow blowing compressed air at a deeper depth since the VIIC/41 could go deeper?  Otherwise, If the u-boat were below 280 meters blowing compressed air would not be an option...  That Safety Valve is causing me grief!!!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2014, 13:43
Don.
Its hard to remember the figures, I was an EO for a VIIC/41 U995 and a VIIC  U(926) and cannot remember any different settings of the reliefvalves. The crush depth was really an extreme depth and we were never even near it. The max operational depth for a VIIC/41 was 120 m and a VIIC 100m we stayed within those limits. To blow ballasttanks at 250 or  280 meters would be a desperate emergency and I don`t believe the boat was designed for such an operation. I guess in a situation requiring a blowing at that depth,  you try anything and if the reliefvalve would blow, you adjust the valve. I feel like citing my old submarine teacher and RN commander (E): Why spend time, effort and money to learn how to escape from very rare and impossible situations, better to learn people how to operate the boat within the design limits preventing you to get into such situations. At 280meters you are lost anyhow and I guess it isn`t  worth while to worry about the reliefvalve setting.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Oct , 2014, 18:50
Hello Mr. Tore,


As I learn more about these valves, I believe I have to go back and revisit the Negative Buoyancy tank blowing valve.  I have labeled 3 valves related to the air pressure to blow the tanks.


A.  This valve is a manually controlled pressure valve that sets the blowing pressure to 25 Bar from HP
B.  This is the red hand-wheel valve that is used to provide blowing air to the Negative Buoyancy tanks
C.  This is a pressure relief valve to limit the air pressure


See the attached drawing...  Comments?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Oct , 2014, 19:57
Hello Mr. Tore,


Can you tell me if this is correct?



High Pressure = 200+ Bar
Ballast Tank Blowing Pressure = 25 Bar
Low Pressure = 12 Bar
Negative Buoyancy Tank Blowing Pressure = 25 Bar
Regulating/FRO Tanks Pressure= 10 Bar
Regulating Tanks Pressure = 10 Bar


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2014, 01:38
Hello Mr. Tore,


As I learn more about these valves, I believe I have to go back and revisit the Negative Buoyancy tank blowing valve.  I have labeled 3 valves related to the air pressure to blow the tanks.


A.  This valve is a manually controlled pressure valve that sets the blowing pressure to 25 Bar from HP
B.  This is the red hand-wheel valve that is used to provide blowing air to the Negative Buoyancy tanks
C.  This is a pressure relief valve to limit the air pressure


See the attached drawing...  Comments?


Regards,
Don_
Don.
The is a classical blowing arrangement for a VIIC.
  A is the mainblowing valve (red handwheel stb side) not set to any pressure but, controlled manually by the blowing man for port and stb. Q within the pressure range set by the reliefvalve C and checked by reading the manometer.
 B is not a blowing valve and has no special valvecone for pressure regulation, it is a shut off valve to the common venting and blowing pipe between port and stb. Q. This valve is shut when the system is in venting configuration.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2014, 02:42
Don.
I am not sure I understand fully what kind of figures you want to check. There are a number of different pressures figures. Operating pressures, reliefvalve pressures, testpressures and differential pressures. Fi. the MBT blowing pressure 25 bar is not the usual blowing pressure. Blowingpressure is manually controlled to the pressure required within a pressure range I believe up to 25 kg/cm2 and I guess the max ballasttank blowing panel is having a relief valve pressure set to 30 kg/cm2. I don`t remember all the figures but I guess most of these figures are mentioned in your book U boat information translated by Maciek.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Nov , 2014, 11:47
Hello Mr. Tore,
 
I was thinking again...  This setup looked like the Blowing Manifold for the ballast tanks; where there are 2 HP input lines with manually adjustable pressure valves.  A primary and a backup line in case the primary line freezes.   They reduce the HP pressure and use the individual blowing (on/off) valves for blowing the ballast tanks.  This setup looked exactly like the Q tank setup; where you could set the blowing pressure with the manually adjustable pressure valve and then use the on/off valve to blow the Q tanks.  That way you would not need to set the pressure each time you blow the Q tanks.


However, you are the expert and I am just the student who continues to ask many questions to learn about the U-Boat.  I don't believe I will ever be at the point where I don't have questions???  Thank you for the quick response...


I have just uploaded to dropbox the latest version of Skizzenbuch.


Updated pages:
90 - 91 Junkers
98 - 101 Bow and Stern Buoyancy Tanks
189 - 191 Blowing Manifold
212 - 213 Oxygen
348 Corrected U-995 Info
349 - 350 Listening Devices -  GHG, Balkon, KDB, and UT
359 added external views of Bold


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Nov , 2014, 20:05
Hello Mr. Tore,


I was looking through my photo files and I noticed several things about Kaura / U-995....


The photo at with the mountains in the background; there is no lower gun deck, only the upper one.  Was that removed when it became the Kaura S309?


There is a photo of Kaura with people lined up and assending the stair case to the stern hull entrance.  In addition, there is a Norwegian flag on the pole beside the stair case.  Was Kaura a museum boat before it went back to Germany?  It surely looks so...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2014, 02:58
Don.
When the Norwegians introduced the VIICs and VIIC/41 submarines as Nato subs. their operation would be different from the germans. The AAguns or foredeck gun would not be necessary, in addition the boats had schnorchel and spent more time submerged. The guns and wintergarden created a considerable drag submerged, reducing the underwaterspeed. So we removed both the wintergarden and guns and designed a new aft towercasing. It is not a copy of the old VIIC tower from the 1940/41 as can be seen on the photo below.
U 995 museum.
I assume the photo you are referring to is the one below. The U 995 was never a museum in Norway,after my time on board she had a refit and was not used as a frontline sub.any more, but more like a training and research vessel before she was faced out and laid up, I guess in 1962. As from 1965 there were confidential talks and plans to return the submarine to Germany as war memorial. It took a long time before it became a reality as it was still a touchy subject still close to the war. In the early 70ties she was converted to a museum in Kiel and the official handing over sermon took place at Laboe October 2nd. 1971. the photo of the event is below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2014, 07:17
Don.
 I have checked you Skizzenbuch (5) and have a few small remarks.

There is a misprint in paragraph 1 mentioning bow buoyancy tank instead of stern buoyancy tank.
On page 101 you have a double description of the Junker which is a bit confusing in addition it has become a two cylinder diesel. The correct text would be: The Junker compressor is driven by a single cylinder opposed free piston, two stroke diesel............
The whole Junker exhaustvalve arrangement is an assumption as we have no original drawing or description of  the design.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2014, 09:00
Don .
The venting system of a submarine is one of the most important systems and I just had a look into your description of the system in your Skizzenbuch. On page 281 it seems to me that you have mixed up the MBT 3 emergency shutoff ventvalves with ordinary vents. I have made a sketch based on Plate 16 and 28 below which give an explanation of the system.
The venting of MBT 3 is done via two ducts going through the port and stb. regulating tank and then outside the pressurehull to the port and stb main ventvalves operated from the controlroom. The saddle tanks 2 and 4  have a similar arrangement however the venting ducts goes directly outside the pressure hull and  2 and 4 stb merge into a common ventvalve as port tanks do as well. In the ducts, at the point where these ventducts leaves the tanks there are emergency shut off valves which normally do not take part in the venting of the tanks, they are normally always open and only used in the event of a damage to the outside duct.
A third valve is placed in the MBT 2 and 4 ducts, coloured green on the drawing. These are the isolating gatevalves, shut when the saddletanks are in fuelconfiguration. Otherwise they are always open.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Nov , 2014, 10:32
Hello Mr. Tore,


Is that page 281 of the current Skizzenbuch file loaded into dropbox currently?  Almost every time I make changes, the page numbers change.  Currently Page 281 just contains drawings from u-historia about the MBT 2 and MBT 4 hull valves, and the MBT 2 dual residual valve and hand-wheel in the control room.


Page 282 deals with MBT 3 and the commom trunk valve that is operated via a lever in the control room which is also from u-historia.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2014, 12:05
Don.
Yes, I believe you have copied the drawings and may be the text. What is confusing is probably that the emergency shut of valves are called vent valves, giving the impression that they are used in the normal tankventing operation, whereas they are practically never used for venting. They are emergency valves. See drawing below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Nov , 2014, 12:36
Hello Mr. Tore,


I am not permitted to change their drawings, byt I will add a note about the errata.  I will poat a new Skizzenbuch late this evening which will have 10 additional pages as well...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Nov , 2014, 12:49
Don.
As the emergency valves  have a purpose in the system it is absolutely worth while to explain. A ventpipe outside the pressurehull only hidden by a fragile casing is very susceptible to for inst. aircraft machinegunfire, a puncture of a ventpipe shall cause all the air to escape from the ballasttank which might have a serious consequence that's why these valves are important yet very rarely used.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Nov , 2014, 16:49
Hello Mr. Tore,


Thanks for the explanation...  I just assumed the valves were redundant vent valves.  I sure am getting an education!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Nov , 2014, 18:54
Hello Mr.Tore and Maciek,


I uploaded to dropbox the latest version of Skizzenbuch with the following changes:


Plate 17: Blowing pages 190 - 199
Plate 21: Sanitary Systems pages 226 - 227
Page 291 - Emergency valves
Page 295 - Drawing of valves and locations
Page 327 - Toggle Switchboard


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Nov , 2014, 00:29
Don.
I checked your latest Skizzenbuch and have a  few remarks. Plate 17 page 190-199 on the blowing distributing panel you have omitted the branch no 11 being the supply to the blowing panel for the regulating fo.tank and the Q tanks. On page 197 emergency blowing is just a minor thing, referring to a geographical area as the eastern sea, I guess it should be the Baltic. I  have made a sketch of the venting system of MBT 3 showing the valve arrangement and the venting ducts going through the port and stb. regulating tanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Nov , 2014, 10:42
Hello Mr. Tore,


Originally, I had an item No 11 for the blowing manifold...  I thought it was strange; the U-Boat Manual had an item 11, but only 10 in the drawing....  So, I deleted the 11th entry.  Now, I put it back...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Nov , 2014, 14:31
Hello Gentlemen,

Originally, I had an item No 11 for the blowing manifold...  I thought it was strange; the U-Boat Manual had an item 11, but only 10 in the drawing....  So, I deleted the 11th entry.  Now, I put it back...

the item 11 is hard to notice - I have marked it with red circle.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Nov , 2014, 00:33
Hello Mr. Tore and Maciek,


I looked at that blowing manifold many times and missed item 11.  Perhaps I need to get those cataracts taken care of very soon!


I uploaded a new version of Skizzenbuch to dropbox this morning...
Page 292 -  Tore's MBT 3 Drawing and info
Page 192 -  added item No 11
Page 197 -  changed to "Baltic"
Page 199 -  added Bordabschlusse und Klar Tafel - or light panel (info from Maciek)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2014, 02:17
Don.
I have checked you last update of your Skizzenbuch and it seems to be OK. Only a few minor remarks ( Can`t resist. ;D ) You have changed to Baltic one place but East Sea is still in the text. I believe the east sea nomination derive from that we who lives near the Baltic usually call the Baltic sea for the East sea, but in English I guess Baltic  would be the correct name.
You are using the word close when you are referring to items to be shut. In Royal Navy submarine English one of the first ting you are told is, never use the word close, always shut. The reason is that for a vital word on board a submarine like shut there has to be only one word for shut, any other word is forbidden to prevent misunderstanding or confusion. I am not familiar with the US submarine customs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Nov , 2014, 13:01
Hello Mr. Tore,


I fixed the one East Sea to Baltic Sea.  In addition, I did a WORD search and replace on the word "close, and closed" and replaced them with "shut"... 


I believe this will close (OOPS.. SHUT) the issue.


Latest Skizzenbuch was uploaded to dropbox.


Kind regards,
Don_


PS - if close or closed is in a drawing image, than that will remain because WORD can't read images.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Nov , 2014, 00:54
Hello again Mr. Tore,


I went through Skizzenbuch and I believe there were 6 images with the word/words "closed" in them.  I went to my images folder and modified the original images and pasted them into Skizzenbuch.  So, I believe all instances of "closed" has been removed form the latest revision of Skizzenbuch, and it's in dropbox...


Regards,
Don_


PS: So far I have learned two words; SHUT and SCHNORCHEL...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2014, 01:23
Don.
What a relief, now we don`t have a disaster by giving unclear orders. ;D
I just noticed you have in your Skizzenbuch some interesting photos on the HP blowing and exhaustblowing of the main ballasttanks. I have put same up to show a typical surfacing procedure.
To the left is the controlroom engineer  blowing all the main ballasttanks having his eyes fixed on the blowing manometers ready to shut the main blowing valve when the order from the CO is stop blowing.
The next photo shows the controlroom engineer again having his eyes fixed on the manometer adjusting the exhaust gas pressure for MBT 1 and 5 which means he has finished blowing 2 and 4 saddletanks ( if not in fueloil configuration) and is ready to switch over to MBT3 as soon as 1 and 5 are empty.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2014, 06:32
Don.
Referring to your latest Skizzenbuch I shall just mention a couple of beautyspots. Page 76 explanation of a gatevalve. The gate valve, particularly those used as isolation for the ventducts of fuelballasttanks 2 and 4, are more like a substitute for blindflanges. The advantages above a blindflange is they are easier to shut than putting in a blindflange. Yet ,when not in use, they have the "gate" out of the way thus no obstruction in the pipeflow. The construction is as can be seen on my picture below. The use of a inboard ventilation valve may be a bit misleading for an outboard gatevalve as the ventilation valve has a different shutting arrangement.
A very minor remark. On page 251 you are correctly referring to type XIV as a Milk Cow, however the German name is Milch Kuh and not Kul.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Nov , 2014, 17:58
Hello Mr. Tore and Maciek,


I corrected the spelling error for 'Milk Cow" - Kuh


I added Mr. Tore's rendition of the two crewmen using the blowing valves and removed the two lone photos.  That way I don't need to change the page numbers and the index.   The latest version of Skizzenbuch is in dropbox.


Also, I uploaded a new folder "U-Boat Museum" which contains about 40 images of wiring / e-motor / speed controller information.  Mr. Tore, you are welcome to what's there...  Maciek has access as well.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Nov , 2014, 00:14
I re-sized the files in the U-Boat Museum folder to 8.5 x 11.75 to get rid of the blank space and rotated the files to be up right...


Regards,

Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Nov , 2014, 02:28
Don.
Where do I find your U boat Museum folder? Dropbox? It is not yet there as far as I can see.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Nov , 2014, 11:29
Hello Mr. Tore and Maciek,


Sorry, I just assumed since you had access to the Skizzenbuch folder that you would have access to everything under the folder.  I just sent you all a link to the U-Boat Museum folder,


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Nov , 2014, 12:02
Don.
Got it looking forward to reading it, Working on scanning the high voltage scheme.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Nov , 2014, 23:47
Don.
Your Skizzenbuch is increasing in volume yet there are further items to consider worth while  to be included.
The VIICs are equipped with possibly one of modern technology`s last and most advanced use of mechanical transmissions. Hundreds of links, rods , traveling nuts, bearings and bevelgears installed required a substantial maintenance for safe operation. Greasing and lubrication is one of the major factors. The greasing system consist of two major greasepumps with container, one  A situated in the engineroom stb aft side next to the main engine clutch handle, the other B, in  the forward torpedo compartment stb side just aft of the torpedotubes ( next to the visitor door on museum U 995). From these grease pumps pipes goes via a hullcock through the pressurehull to a selector/distributor and then to various difficult spots outside the pressurehull. The outboard selector is controlled by a handle inside the pressurehull as can be seen on my sketch below. Please note the details on the construction are assumptions from my side as no drawings are available.
Further to the system are grease cups practically fitted everywhere there are moving parts,  travelling nuts would have a flexible grease hose as can be seen on the Kingstons on plate 28. Most of these Kingston greasing spots are fed by greasecups in the control room. Many of the grease cups of the museums U 995 are gone, only some pipes and under parts of the grease cups remains.
The system was extensive and labour consuming and we had a PO responsible for the weekly greasing routines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2014, 01:42
Don.
High voltage scheme.
I have finally been able to scan the high voltage scheme the original, as I told you, is pretty shot. Before I continue, could you make use of this quality? I am afraid the original isn`t much better.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Nov , 2014, 20:32
Hello Mr. Tore,


I believe these greasing pumps are hand operated and not electrical, am I correct?


Regards,
Don_




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Nov , 2014, 23:25
Don.
As far as the greasepumps concerns they were handoperated, you clearly see the handles on the photo below. The lubricators (Gruetzner) were rod driven by the main engines. These lubricators were supplying oil droplets to points were the dieselengine main luboil system could not be used. They a pretty easy to locate up front of the engines inboard port and stb.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Nov , 2014, 00:20
Hello Mr. Tore,


Thank you for the quick response...  I updated Skizzenbuch and the "Maintenance" section is on pages 262 and 263, and it's in dropbox.


Good night, it's 2:20 am here in Georgia.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Nov , 2014, 01:58
Don.
Checked Skizzebuch 10 page 262 and 263, OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Nov , 2014, 23:54
Hello Mr. Tore and Maciek,


After going over some of the switchboard schematics from the U-Boat Museum, I realized I was confusing the Dead Slow speed with the single switch option Crawl or Creep speed.  This may have been an option on the older switchboards, but the current manual schematic we have it looks to be disabled.  Craw or creep would have put the speed at around 30 RPM (around 0.8 knots).  I guess the Germans needed more speed while submerged, and not less...


Mr. Tore have you ever heard of the creep or crawl speed while submerged in Kaura?  I guess Maciek will be glad I have finally seen the light!!!  I have up loaded a corrected version of Skizzenbuck into dropbox,


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2014, 11:55
Don.
I never heard about creep or crawl speed submerged, apart from dead slow we had silent running.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Nov , 2014, 12:58
Hello Mr. Tore,


I have a question about "Plate 6:".... The Main Drainage Pump can pump water into a drainage port or MBT 3.  Both end up sending the pumped water into the sea because MBT 3 has the flood valves open and the air pressure will force added water out the open flood valves (Kingstons) while surfaced.  Then again while submerged any water pumped will end up into the sea as well.  So is the drainage port redundant?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Nov , 2014, 13:09
The only thing I could forsee is if some of the blige water had oil.  Then it could be pumped into MBT3 so not to leave an oil slick.  The oil would remain in MBT3 floating on top of the water residual.


Don_   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Nov , 2014, 13:19
Hello Mr. Tore,


I believe Silent Running was a test ran to determine which speed produced the least amount of noise.  Was that done with one prop or two?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2014, 22:59
Don.
Your assumption of the use of bilgewater outlet into MBT 3 is correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2014, 23:20
Don.
Silent running was not a testrun. It was an order given to be as silent as possible trying to eliminate cavitation noise ( propellers), crewnoise and shutting down noisy auxiliary machinery. Once a year we had noisetrials laying semi submerged surrounded by microphones, starting up each axillary machinery one by one, recording the noise to establish the noisepattern in view of which items could be run under silent running condition, a kind of noise certification. You could run both propellers or one depending upon you noise pattern, (Cavitation)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Nov , 2014, 20:42
Hello Mr. Tore,


On Page 82, where the crewman is using a claw tool to change the ballast tank configuration.  If the hand-wheels were removed from the gate valves, then would the claw tool still do the job or would he have to use a different tool?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Nov , 2014, 00:28
Don.
The tools you mention were not only tools for the fueloil / ballasttanks configuration, but used for many type of valves. What you call a claw tool is a valve wheel wrench used on valves having wheel and hard to move. The other tool is a T bar extension tool used on valves  having no wheel and which could have an extension up to the deck ending in a small square supported by a connection in the deck or simply a valve deep down without a wheel or lengthening rod. In the case of the gatevalves for fueloil/ ballast tanks 2 and 4 they would act as blindflanges, very seldom used and as such I guess most EO would like to remove the wheels using T bar extension to reach the valves. If you look at the picture below you shall see permanent valve extension to the  in the deck for valve frequently used. For these connections you used the T- bar as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Nov , 2014, 00:04
Hello Mr. Tore,


I added a maintenance section to the index and to Skizzenbuch.  Also, I added 2 pages to the torpedo section to get a better explanation of the firing valve and pilot valve, and I went through the complete book and corrected any wording or spacing errors.  Just about completed except for a page or two on the speed controller later...  I believe Skizzenbuch is getting very close to finished.  Also, I uploaded the latest version of Skizzenbuch to dropbox


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Nov , 2014, 01:48
Don.
As you are about to finish your Skizzenbuch I would like to mention a last item worth while to include, the clutches and the shafting system.
 In addition to the clutches described in the emergency manual operation of the hydroplanes, there are several clutches in the shafting system as well as clutches in the Roots blower of the GW engines.
The main clutches between the main engines and the E-motors/generators are double cone friction clutches pneumatic hydraulic operated and I have made some sketches and photos previously on this thread.
The double cone tail clutches, manually operated, are situated just after the E-motors/ generators and the Michel thrust bearings.
The Roots blower clutches are situated in the aft end of the main engines having  maneuvering handles extended to the maneuvering stand up front towards the pressurehull sides. The rods of same are  connected to the aspirated air inlet shut off valves and interlocks as well.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2014, 06:50
Don.
My description of the pneumatic/hydraulic clutch between the main engine and E-motor/generators can be seen on page 88 and 89 on this tread.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Nov , 2014, 21:05
Hello Mr. Tore,


You are correct and I will add the clutches. Do you have any good photos of the back end of the Diesel engines with the clutches?  I believe the drive was both manual and hydraulic???.  I pulled a photo from u-historia and they show the e-motor clutches and levers to engage.  Was this only manual for the e-motors?


Also, there is a photo of the diesel engines from the back and there are three hand-wheels shown.  My guess is the two large ones are for manually engaging the diesel drive shaft clutches...  How do they engage the Supercharger clutches and I believe they are engages while the diesel engine is running.  I will post the photo.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2014, 02:19
Don.
The only pneumatic/hydraulic operated clutches were the two between the main engines and E motors/generators. As an emergency alternative they could be operated manually by the wheels shown on your photo my sketch below shows how they works. If you need further explanation just ask. The third handwheel (small) has nothing to do with the clutches and belongs to the ventilation system.
As to the clutches for the Roots blower they are operated manually from the maneuvering stand up front of the engine. However on your photo you see the casing of the clutch
just below the blowercasing. As there are interlocks and other elements in the manual operation of these clutches I shall revert to that system in a different post. You are right in your assumption that the Roots blower is connected while the diesels are running.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2014, 07:06
Don.
The clutches for the Roots blower on the GW engines have to be interlocked for several reasons, for the direct reversible engine an interlock is needed to prevent the clutch to be engaged when the maneuvering handle is in astern position, for both reversible and nonreversible engines it is an interlock preventing the clutch to be engaged when fuel handle is in a position corresponding to, at normal load, the enginerevs are below 420 rpm. At the same time the normal aspirated inletair ducts have to be shut when the Roots blower is engaged.
All these functions are obtained via linkages from the manual clutch lever up front of the mainengines as can be seen on the drawing below. There is a slight deviation between the basic arrangement for the direct reversible and non reversible engines. The maneuvering diagram shown is a direct reversible execution. The Roots blower drive is a PTO of the camshaftdrive and having a wrap spring coupling for torsional vibration reasons and a double cone friction clutch as can be seen on the drawing. In order to save the friction lining of the clutches, you would like to engage the clutch at lowest possible revs as the inertia forces caused a heavily wear on the friction lining.
On the MAN engines these clutches were not needed as the turbocharging ( Buchi system) could operate during the whole rpm range as well as astern.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Nov , 2014, 22:46
Hello Mr. Tore,


I have a question about the distribution cock for the pneumatic-hydraulic system...  Should the cock be a change-over cock with a central passage type valve?  My reason for thinking this way;


If the non active cock position provided a path to both pressure flasks so if the pneumatic-hydraulic system failed, then the hand-wheel could be used and it would move the piston via the worm shaft nut and easily move the hydraulic fluid from one side of the piston to the flask with no air compression.  There would be no back pressure???


What do you think?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2014, 00:25
Don.
If you study the systemsketch you shall see the central passage is already there and the handle for the pneumatic/hydraulic system has three positions: In, Out and Neutral, the latter position allows the hydraulic fluids as well as the confined air to shift as there is no volumechange (external air supply) while in manual (neutral) operation position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2014, 12:44
Hello Mr. Tore,


Thanks for the response...  Would the valve cock handle be spring loaded to return back to the neutral position connecting the channel between the two flasks?  That way if there were a failure of the Pneumatic-hydraulic system, then the manual operation would not require any distribution cock lever change?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2014, 14:14
Don.
The handle for the pneumatic/ hydraulic system is springloaded but only to lock the cock in the selected position, the lock is released by pushing the knob on the top of the handle. In the unlikely event of loosing the pneumatic pressure and it was vital to have the clutch engaged, I guess you could keep the clutch in position by moving the cock as indicated on my sketch however  this was not a standard position. I never tried it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2014, 23:01
Hello Mr. Tore,


I wrote a section "Drive Propulsion Systems.pdf" and it is now in dropbox.  I quit building pages in the 3 Skizzenbuch sections because of file size.  I'm just guarding against file corruption this late in the book write-up because of MS Word problems with large files.


If at all possible would you please check the 8 pages?  And make any suggestions that you believe is needed.


Kind Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2014, 07:18
Don.
I have read your 8 pages which seems to be OK apart from a couple of obvious misprints. It looks as if you have copied some old manuals as to the various diesel  operations as there are no mentioning of the alternative schnorcheloperations which you have described in your Skizzenbuch previously.
I guess a more extensive explanation of the thrust bearing would be worth while. The thrustbearing is a Michell ( pronounced Mitchell) type of bearing having thrustpads on both sides (ahead and astern) of a forged (intergrated) disc on a shaft stub which turns in ordinary slidebearings. The pads have whitemetal slidingsurfaces towards the disc and a ridge or knob on the backside able to tilt the pad, creating a wedgeshaped oilfilm between the thrustpad and the disc during rotation. The bearing has a selfcontained lubrication system with an oilsump which is watercooled either from the central cooling pipe or from the compressor coolingwater pump, see my sketch. Red is pressureline, blue is discharge. The bearing housing has a sturdy foundation secured to the pressure hullstructure (red) able to absorb the thrustforces to the submarine. Kindly note that the British version of coolingwater plate 13 is not correct on this point, the original German is OK. Aft of the bearing housing is a PTO to the propellershaft revs counter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Nov , 2014, 23:46
Hello Mr. Tore,


Thank you for the info on the thrust bearing...  I updated Skizzenbuch and the Propulsion Drive System starts at page 352...  The latest version of Skizzenbuch is in dropbox.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2014, 00:51
Don.
I checked your latest Skizzebuch page 352 OK. However I accidentally discovered on page 312 and 313 you have two almost identical drawings of the MAN reversing system. In your cramped space I guess only one drawing of the system is sufficient and page 312 has the best copy. On page 308 and 311 you have the same for the GW engine page 308 best.
Further you better check page 315 and 317 which has the same crossection drawing as well as page 314 and 316 which alltogether would save you some 4 pages.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Nov , 2014, 11:16
Hello Mr. Tore,


Those duplicate plates were intentional...  There are the plates with some English notation and there are the original plates with only German text.  I have done this throughout the book with the English index and the pure German indexes, and the English noted plates and the pure German plates.  It was sort of a verification of the information presented to the reader.


This duplication has definitely increased size of the book.  If the book is ever published, then perhaps the publisher may want to remove the German-English duplication.  For my own personal view this will stay for when I commit it to print my one own personal copy and place the pages into my black leather covered metal post binder.  That post binder cost me just over $245 USD and is expandable to any number of pages.


Thank you for noting the pages...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2014, 23:38
Don.
I guess your Skizzenbuch shall be some book. Be aware of that some of the translated copies of the system plates have some mistakes both with regards to the text and the sketch particularly with regard to pipelines crossing. Re: cooling waterpipes thrustbearings and cooling waterpipe spare cooling waterpump main engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Nov , 2014, 22:35
Hello Mr. Tore,


When I look at the Papenburg depth gauge between the two control stations in the control room, it looks like the gauge is in two parts.  The forward water column looks to indicate the height of the periscope to a point.  Then the aft water column on the right looks to indicate the periscope head/eye at a position above or below the water surface.  Is this basically correct?


The question I have is this gauge is in the control room, and the captain is in the tower working the attack periscope.  Does the captain use/need the Papenburg depth gauge.  I would not think an experienced  captain would need the gauge because he could see when the periscope is above or below the water.


I don't recall any linkage between the periscope pneumatic-hydraulic drive and the Papenburg depth gauge...

Also, what is this device on the other end of the control room.  It is two long tubes with a perforated metal protective covering?  See photo...


The huge 0 - 25 meter depth gauge; what are the reference points? At 25 meters is that to the surface from the bridge, deck, keel?  If it were the keel, then it could never get to 0 meters...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2014, 02:16
Don.
The two long tubes with the metal covering are the level gauges for the port and stb fuel/ regulatingtanks (saddletanks) 1 and regulating tanks 2, you have 2 on each port and stb side.
All the depth gauges shows the depth from the keel bottom to the surface and the large depthgauge to 25 meters was used to navigate at periscope depth.The only time the gauge show 0 was in drydock :D  It was shut off when going deeper.
The Papenberg depth gauge is important as some time during attack you might have difficulties in keeping stable depth, thus the periscope which should not be too heavily exposed would require a constant adjustment while CO is busy with bearings and other attack parameters. I guess he could leave that adjustment to another periscope adjustment station next to a Papenberg depthgauge. If you look at the hydraulic system for the tower you are able to locate two control levers for the attack periscope one locally at the periscope and one off the periscope having a selectorvalves to choose one of the two. I guess on some of the IX types you had an indicator connected to the winch which gave, combined with the Papenberg, a direct indication of the periscope exposed above the surface. I can`t remember this device on the VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2014, 07:15
Don.
The Papenberg depth gauge, named after the inventor, a German naval engineer Heinrich Papenberg (not Papenburg)  is used for a quick response and accurate depth control at shallow depth for different purposes like accurate periscope depth and schnorcheldepth. It is a watercolumn gauge having connection to the sea via shut off valves on one side and a sealed aircushion on the other side. The scale could variy like having a sketch showing the depth in relation to the schnorchel mast floatvalve or the periscope. The sketch shown below shows the navigation periscope position and I think the air inletfloat of a ringfloat schnorchel mast. I guess in the tower it would be the attack periscope.  As far as I remember you had to shut the hullcocks at 18 meter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Nov , 2014, 22:48
Hello Mr. Tore,


I uploaded the latest Skizzenbuch to dropbox and the info on the Papenberg gauge is on pages 183 - 186...


Thank you for all your help!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Nov , 2014, 00:39
Don-
I have checked your skizzenbuch pages 183 and 186 and have a few remarks. I realize I forgot the inclinator gauge next to the Papenberg, this gauge is called the inclinator and works as you describes, the advantage of this design is that it is more accurate and easier to react on than a conventional air bubble in a curved glasstube. The instrument showing the shaft rpm is called a tachometer. The small manometer next to the 25 meter depth gauge is not the main depthgauge for larger depth, it is a check manometer for the depthgauges. I am afraid somebody nicked the big depth gauge for the larger depth on old museums U 995, but on the photo below you see the depthgauge we used at depth exceeding 25 meters.
Otherwise the pages are OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Nov , 2014, 17:10
Hello Mr. Tore,


I made the corrections to Skizzenbuch and uploaded the latest version to dropbox,,,


Also, a welcome back to Maciek from his vacation (Holiday), I hope it was pleasant and relaxing my friend...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Nov , 2014, 00:41
Don.
Your Skizzenbuch checked OK except I believe a few words have been omitted on the deep depth gauge as you state :"  when the submarine is running at depth submerged ...."   It is used for depth beyond 25 meters.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Nov , 2014, 01:02
Don.
Direction of propellerrotation.
The opposite direction of the propellerrotation is not unique for a submarine, but counter rotation ( usually outboard rotation) for a twin propeller installation is normal for any ship having twin propellerinstallation. The reason for such a counterrotation is that the torque created by each propeller is neutralised. If both were rotating the same direction, the vessel would drag to one side which  constantly had to be compensated by the rudder and you would have a loss of energy (speed).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2014, 07:38
Don.
As a professional in electrics I wonder if you have noticed the two way of cabling on the museum U 995. The neat original and the post war type. We have many times warned against copying the details in this submarine as many details are not original. The fluorescent lightning was of course not original as well as the postwar cabletrays running right through the whole interior. In the engine room these trays are an obstruction for pulling a main engine piston and the watertight bulkhead passages are just plain holes as can be seen on my photo below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Dec , 2014, 10:51
Hello Mr. Tore,


Thank you for noting the cabling...  I believe I will add that to Skizzenbuch.  In Addition, Maciek has provided me with a great deal of information after his Holiday and I'm working on that as well.  It will take awhile before the next version of Skizzenbuch is available.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Dec , 2014, 00:10
Don.
Your Skizzenbuch seems to be a never ending project. Today I just mention a simple yet important detail in the structure strength of the pressurehull. The two torpedoloading hatches creates a large oval hole in the pressure hull which implies a cut of two frames causing a severe weakening of the structure. This is compensated by introducing two strong removeable supportbeams which substitutes the cut away parts of the two frames. Sometimes during a long stay in harbour we used the forward torpedo hatch as an easy access and we removed these beams not just for the torpedoes but even for the crew and guests.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Dec , 2014, 00:16
Don.
In your Skizzenbuch page 48 and 49 you state  the measuring tubes for both the regulating tanks 2 and the fueloil/regulating tanks 1 are for measuring fuel in the tanks.
 As you know the regulating tanks 2 port and stb have only water for compensating weight changes, you need that capacity just for regulating water and thus cannot be used for fuel, whereas the smaller fueloil/regulating tanks no 1 port and stb. can be converted to fueloil tanks. The water gauges for both tanks are primarily used for accurate measuring the water contents, but can of course for fueloil/ regulating tanks no 1 port and stb. be used for fueloil measuring as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Dec , 2014, 22:51
Hello Mr. Tore and Maciek,


I just went through a major update to Skizzenbuch...  I changed the font size (smaller) on the 2 index pages so I could have more entries.  I have made the following updates:


48 - 49  fuel / Water  Per Tore and Maciek
84  Tools  Per Tore
92 - 93  Junkers exhaust  Tore
115  Aux water cooling  Per Maciek
136  Aux lubricating Pump  Per Maciek
183 - 190  Panenberg, Inclinometer, Depth, Tachometer, Telegraph  Per Maciek
265 - 259 Periscopes  Per Maciek
282 Torpedo Tube Hatch  Per Tore
352 - 353 Rotary Converters  Per Maciek
354 Update Rotary Schematic  Per Don_
366 - 374 Propulsion and Clutches  Per Tore


I placed the latest version of Skizzenbuch in dropbox and I do welcome comments...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2014, 02:24
Don.
 I have read through the Skizzenbuch pages mentioned by you and have following remarks.
Page 48-49. Fueloil bunker and regulator tanks 1. You use the expression "air is blown into the pressure hull". You are actually venting the tanks into the control room. As these tanks, when used in fueloil bunker configuration, are not connected to the compensating water system and as such have to have another transfersystem, LP air is used for the transfer. The tanks are vented trough sightglasses and muffler into the controlroom bilge.
Page 4 "T" tools you mention "....have a square socket to fit over the deckdoor screw down lock of the....". Many (most?) of the valves have an elongation of the valvespindle ending in a square up to the deckplates for easy access by the T tool. Thus no "doors" or hatches needs to be opened, see my photo of the engine room and casingdeck.
Page 92-93. As the Junker compressor is a free piston two stroke diesel it is very susceptible of accurate balancing. It is a single cylinder engine, not two cylinder as stated. Having carbon deposits on the opposed pistons due to bad scavenging and combustion creates pistoncarbon deposits (unbalance) and shorten the maintenance intervals, thus increased exhaust counter pressure should be avoided.
May be you should emphasize that the Junker exhaustsystem sketches made by me is an assumption from my side as we have no original drawings of same.
Page 136 Aux. luboilpump. The pump you describe is the fueloil transferpump which can be connected to the luboilsystem and thus used as an auxiliary luboil pump.
Otherwise  I enjoyed quite a few interesting, unknown to me, photos- Macieks ?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 04 Dec , 2014, 09:21
Tore, look at this lol: https://www.youtube.com/watch?v=MzA1brBuhFc
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2014, 09:56
Unbelievable, I`ll show it to the grandchildren. Reminding me of the longest submerged trip I ever made with good old KNM Kaura ex U-995. We were testing out long time schnorchling and was submerged for 28 days Norway-Greenland and return. We had no radio contact except Rugby and the time could be pretty boring so we let our radio operator be our entertainment man making musicprogrammes based on our stock of LPs. Just that autumn a new rock and roll was introduced on the market and we got it over the loadspeakers twice an hour during 28 days. The name of the melody: Rock around the clock tonight ! The only rock and roll I know. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2014, 12:14
Hello Mr. Tore,


Listening to Rap Music for 28 days would have been maddening!  By the way "Rock around the clock" was about the first "Rock n' Roll" songs ever, and it was performed by Bill Haley and the Comets!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2014, 20:27
Hello Mr. Tore,


I have corrected the following:


47 - Reg tanks
84 - Tools
91 - Junkers  (the 2 cylinder) that was getting ahead of myself when typing with 2 fingers.  I never learned to type, so I have limitations!  I was supposed to type "a single cylinder 2 piston diesel engine"???  also I added a note about the exhaust valve being a logical estimation...
136 - pumps



Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 04 Dec , 2014, 20:55
Listening to Rap Music for 28 days would have been maddening!


My tolerance for this kind of music ends long before a single song is over. It is only bearable when I turn on the "audio professional analyzing mode" (which means I would have to work on it) - in that mode your brain makes it possible for you to survive endless loops of the same 5 seconds over a whole day (any kind of music), something that others would call torture. After I've switched my work (sound engineer) from music to movies I've stopped listening to music at all and enjoyed the silence.
But I've also stopped watching any movies during a long period of that time. When I've first saw a full movie after 7 years (as a continuing story and not in weird loop fragments for work) the emotional influence on me while watching it was extreme. I think frequently watching movies clearly has an impact on how you brain handles emotions, maybe we are all always kind of saturated to an unnatural permanent level of emotional input.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2014, 21:40
Yep!!!


I know what you mean.  I purchased a Samsung 55 inch HDTV with 3D and a Bose sound system about 2 years ago!  We moved to the Atlanta Georgia area over a year ago and purchased a new home.  I got the basic internet package (20 mb) with just has local TV channels,  Since I have been working on Skizzenbuch, I've probably watched 2 Blue Ray DVDs in the past year. I like the quiet as well!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Dec , 2014, 00:59
Hi Gentlemen,

Page 136 Aux. luboilpump. The pump you describe is the fueloil transferpump which can be connected to the luboilsystem and thus used as an auxiliary luboil pump.

I would rather say that it is inversely. German documents say:

Quote
Auxiliary lubricating oil pump.
           
The auxiliary lubricating oil pump serves for the lubricating of the engines before start-up, and backs-up the attached engine oil pumps in case of failure.  The pump is an electrically driven vertically arranged screw pump and supplies 38 m³/hour of oil at a discharge head 50 of meters H2O with at least 5 meters suction inlet head.  The auxiliary lubricating oil pump can be used by change-over for the distribution of fuel oil.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2014, 02:16
Maciek and Don.
Maciek is absolutely right, the aux. luboil pump is primarily a luboil pump which can be used  as fuel transferpump as well. It was used as luboilpump every time you started the mainengines and when you turned the engines during maintenance. So to make it clear: due to a shortcircuit I changed the priority it is a luboil pump which can be used as fueltransfer pump not the other way.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2014, 08:44
Don.
You Skizzenbuch 16 seems to be OK. May be you should make the text on the photo of the gauge for regulator tanks 2 port and stb and regulator/ fuel oilbunker tanks 1 port and stb a bit clearer. See my picture below showing the regulating tank 2 port water gauge is aft of the port water/ fuelgauge for reg./fuel bunker tk.1. On stb. side it is opposite, the water gauge for reg.tank 2 is fwd of the gauge for fueloil bunker tk. 1
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2014, 00:20
Don.
In your Skizzenbuch no 16 page 132, you have a nice photo of a pressurehull construction showing the fwd. engineroom area. You text says: "....The two domed exhaustcasting have been bolted in place on the pressurehull." The valves shown on the photo are the pressure hull inlet- and outlet valves for the ventilation system to be connected to the respective airducts going forward to the inlet valves high up in the towercasing and operated from the control room. The system is later modified for the schnorchel system as shown on the image below.
The large duct is the Diesel air supply to be connected to the dieselair hullvalve. See photo. Another interesting detail on this photo is a clear view of the dieselengine hatch which is riveted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2014, 19:00
Hello Mr. Tore,


I have uploaded the latest version of Skizzenbuch into dropbox...


Pages 48 - 49 Per Tore: added text to the gauge drawings
Pages 344 - 345 Per Don_: added Toggle Switchboard schematic from Deutsches U-Boot-Museum in Cuxhaven, Germany.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2014, 01:10
Don.
Skizzenbuch 17 page 48-49. Measuring gauge for stb regulating/ f.o. bunker tk 1 is the aft gauge, thus opposite to the port arrangement, kind of weird as the reg./f.o. tk. 1 is the aft tank on both sides. Your image from the port side is correct. On a very sharp photo this can be seen on the scale, smallest volume 3.600 liter is the reg./f.o. tk. no 1. see photo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2014, 00:04
Hello Mr. Tore,


Page 49 corrected and the latest version of Skizzenbuch was uploaded to dropbox...


That switch was not a logical move on the part of the Germans!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2014, 06:21
Don.
Page 49 checked OK. You still insist the ventilation hullvalves are the exhaust valves on the photo page 132. See my post dec. 6th.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2014, 17:57
Hello Mr. Tore,


I corrected page 132 as per your information and drawing...  I did not forget to do so earlier, but I had to go Christmas shopping with my wife Maureen during the weekend.  It worked out very well for me;  Maureen purchased a very nice (expensive) 26 inch mother of pearl World Globe in a brushes steel cradle floor stand for my library.  I guess Santa Clause came a bit early for me this year!


I uploaded the latest version of Skizzenbuch into dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2014, 22:57
Don.
Page 132 checked OK. Finally we got rid of that exhaust in the ventilation system and can breathe fresh air! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2014, 00:15
Don.
I am reverting to page 84 in your Skizzenbuch and my photo of a T tool from an early VIIC and three of the crew is seen in the engineroom hatch opening. One of my red arrows is pointing at an assumed "T tool". Having looked at several old U boat photos I discovered some uboats have next to the entrance hatches a T support used as a supporthandle for getting in and out of the hatch. This handle was obviously made of steeltubes having a larger diameter than the "T" tools, but looks very much the same and can easily be taken for a "T" tool. I cannot remember we had this support on our VII Cs. Below is an image showing a genuine "T" tool in the engineroom and some T supports on some late and early Uboats, some of them not VII Cs. On one image you see a crew member obviously operating a T tool, however this is an IXA boat. I discussed the T tool elongation earlier on this thread with Simon and he made a sketch showing the engineroom arrangement a small part of it is shown on my image.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2014, 09:15
Don.
Two small details in you skizzenbuch. Page 69 photo of the main engine the description says fuellines goes to the front of the engine where the manual starting and throttle control levers are located-  As you know there are no throttles (gasoline system) on a diesel engine (diesel, direct injection) thus the lever is the fuelrack control lever.
On page 142 you have an interesting photo of the pressurehull and saddletanks with a slightly confusing text as it looks like the stb ventvalve and ducts for the saddletanks  two and four are not yet fitted. It seems to me that you see the connectionflanges for same and the stb duct for MBT 3.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Dec , 2014, 17:59
Hello Mr. Tore,


I corrected the item on page 69 and removed throttle to "manual starting and fuel rack control levers"...


Thank you for finding my screw-up of just pasting in old photos and info...  It sure was WRONG!!!  I have redone that entry and let me know if you think it is acceptable..


Kind regards,
Don_.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Dec , 2014, 00:50
Don.
I guess you are right in your assumption, it could be a photo of the U 995 Restoration. However I believe the stb. MBT 3 vent duct is still visible, not missing. As a curiosity I can mention this particular area just in front of the conningtower stb side was completely smashed and the whole casing was gone during a heavy NorthSea gale  November 1953. We were able to repair it temporally in UK. When returning to our base in Trondheim, Norway the damage was evaluated and the KNM Kaura ex U-995 was on the point of being scrapped.
The rest of your corrections are OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Dec , 2014, 12:29
Hello Mr. Tore,


I made the correction to page 142...  In addition, I added your comments about your November 1953 North Sea experiences.  That is what makes Skizzenbuch so unique; your first hand knowledge!  I hope you don't mind me doing so, and I really appreciate your help.


FYI -  According to the web site where I merge the 3 word documents to create the Skizzenbuch.pdf file this is my 85th version...


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2014, 00:34
Don.
Correction OK, feel free to use the November incident. A small comment on your enginetelegraph description, page 190. You are correctly explaining the order respond from the engineroom, however on the photo you are referring to, the port engine telegraph of the museum U 995, somebody has nicked the responding handle on this telegraph which might be confusing, stb engine telegraph is OK. see my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2014, 19:58
Hello Mr. Tore,


I used your photo and uploaded Skizzenbuch version 86 to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Dec , 2014, 03:25
Don.
Page 86 checked OK.
 A remark on your description of the cooling water system. May be you should deal with the cooling system continuous as you now have pages 120, 126 132 photos of pressurehull interfering with the cooling water system sketches.
As to the cooling water system you have a general central main cooling water pipe going from main coolingwater distribution chest up front in the engineroom all the way to the aft torpedoroom able to serve all coolinginstallations from all the pumps connected to the mainpipe thus it creates a very flexible system.
 The compressors are in general selfsupported by a centrifugal pump for the E compressor and a rotary vane pump for the Junker compressor. Alternative supplies are from the central main pipe and whatever pump may be connected to same. In addition to the cooling components mentioned by you it is a branch off to the cooling of the sternshaft packing boxes and to the aft torpedo compensating system.
On the sketch below I have tried to put up the aft coolingwater system, blue is the suction line, red is the outlet- and green is the supply line and Junker cooling line overboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Dec , 2014, 15:10
Hello Mr. Tore,


About pages 120, 126, and 132...  These photos and many others were inserted into Skizzenbuch in order to get the Plate diagrams on an odd numbered page.  That way when the book is opened to read, the plate text or a photo is to the left and the plate diagram is almost always on the right side (odd numbered page).


I will look into updating and adding your comments in about the water cooling system...


Thanks again.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Dec , 2014, 19:18
Hello Mr. Tore,


I placed your info on the Water Cooling System on page 112 and 113, re-indexed and uploaded the latest version of Skizzenbuch (88) to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2014, 07:02
Don.
Showing the British plate 13 of the cooling watersystem, may be you should mention the red arrow points to the mistake (no connection) in the sketch. There is no connection to the common discharge pipe from the thrust bearing coolingdischarge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Dec , 2014, 12:48
Hello Mr. Tore,


Dose the GREEN supply line cooling water that goes to the Junkers muffler exit to the sea?  It looks so, but I just want to be sure...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2014, 13:48
Don.
If you remember a few weeks back we discussed the Junker exhaust outlet in connection with the aft buoyancy tank ventvalve,  I guess there has apparently been some alteration in the system due to flooding trouble, however I believe the exhaust hullvalve has a watercooled housing where the coolingwater is discharged  in a simpler manor as the main engine system. This means that the Junker overboard coolingwater discharge is via the exhaust coolingwater jacket as indicated by the green lines. See my assumption sketch on page 155.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Dec , 2014, 17:04
Hello Mr. Tore,


I updated page 113 and uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2014, 23:47
Don.
A remark to you last update. I am not sure about the final arrangement on the Junker exhaust cooling watersystem. As mentioned it is obviously redesigned after the system shown on plate 13. As the germans experienced waterintrusion in the exhaustsystem I believe they introduced a second shutoff exhaustvalve almost like the mufflervalves for the main engines.
On the sketch below I have shown this valve in the systemsketch. We have discussed this second valve before, including the grinding , waterblowing system and interlock to the aft buoyancy tank venting. I have to emphasize though: this arrangement is an assumption from my side as I can not remember the details and have not seen any sketches or other documentation on the subject.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Dec , 2014, 10:47
Hello Mr. Tore,


On plate 13 we have valve e3 and the description below.  would that be the same as your rendition of the exhaust valve?  I have also attached a section of plate 13 which has e3 shown...


Regards,
Don_

BORDVENTIL ABGASANSCHLUSZ LUFTVERDICHTER
 
Hull exhaust valve, Diesel air compressor
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2014, 12:44
Don.
e3 is indeed the exhaust board valve which can not be found on the museum U 995. I assume both the exhaustpipe and the valve somehow is removed when making the public entrance door. Down below is a cross section of the Junker compressor, as you see the exhaust pipe is cut and removed a short distance from the exhaust outletport of the compressor diesel part.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Dec , 2014, 19:35
Hello Mr. Tore,


I guess I missed my point about the drawing I posted...  I will try again.  I cut a section from the German Plate 13.  I show a cut off of the junkers exhaust pipe as was done on U-995.  Then I point to the missing valve, and what looks to be the exhaust valve that you provided the internal working.  Is this a possibility?
There is a cooling water line from the external exhaust valve to the muffler as well....


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2014, 00:22
Don.
It is a possibility, however if you look at the internal exhaustvalve casing I don`t think there is an inboard coolingwaterpipe  connection. The waterpipe from the board valvecasing to the muffler I believe is a pipebend to pass the flanges. However it is likely that the internal exhaust pipe is not cooled and the coolingwater outlet goes from the 4.compressor stage coolingwater outlet and into a cooling water jacket of the  board exhaustvalve casing as indicated on my sketch below.
 I am on my way to Africa early Thursday morning, traveling for some 12 hours so I shall be off line for a day or two. Hopefully back on the net Saturday. In the meantime I shall have time on the plane to ponder further on the arrangement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Dec , 2014, 22:51
Hello Mr. Tore and Maciek,


I added some information about the TDC in the torpedo section of Skizzenbuch.  I didn't want to go into great detail, just a view from 20,000 feet as they say.  Please let me know if anything is not correct, or if I missed a vital part.  I did this without adding any additional pages.  The latest version of skizzenbuch is in dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 Dec , 2014, 04:56
Hi Gentlemen,

in the topic of the Schnorchel - on the web page http://www.uboatarchive.net (http://www.uboatarchive.net), few days ago
the KTB from U 480 second war patrol was published. In the end of the document, there are
gathered experiences from the Schnorcheling routine. It is really interesting reading.
http://uboatarchive.net/KTB480-2.htm (http://uboatarchive.net/KTB480-2.htm)

--
Regards
Maciek

PS. U 480 was fitted with Alberich cover.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2014, 17:59
Merry Christmas to all and a great new year 2015... :)


My Christmas decoration is a small LED lit tree with fiber optics that changes colors.  This was placed on top of my 8 year old deskside computer that's slow, but I only type with two fingers at a time.  It works for me!
My OTW Type VIIC U-Boat is 84 inches long with a fiberglass hull, and a plate brass deck and the tower was made from sheet brass and stock brass rods.  My U-96 'Das Boot" was a two year building project for me.  I believe the actual U-96 keel was laid on 16.9.39 and was commissioned on 14.9.40; 2 days shy of a year. The Germans were more efficient in U-Boat building that me.


Enjoy the photos.
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 20 Dec , 2014, 03:33
Hi Don,
 
Thanks for posting pictures. Love the boat. Not surprised it took you two years. I have a second hand OTW VIIC to build so looking forward to that. The tower looks challenging as I am sure you will remember.
I finished off a OTW Vanguard and had it sailing this year. Do you get to sail your boat often?
I liked your SubCommittee articles, on your boat and if I remember you did one on the ballast system too.
Cheers,
 
Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Dec , 2014, 11:12
Don.
You must have a very understanding wife allowing this size of a VIIC model in your sittingroom. I had to fight getting my modest KNM Kaura ex U 995 with painting, my naval sword and the crew photo on my little navy corner.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Dec , 2014, 13:20
Maciek.
A very interesting KTB of the U 480 warpatrol during the time of the invasion as well as from the long schnorcheling . It is astonishing to learn how often they put the boat at rest at the bottom and how they eventually got rid of the garbage. We never laid at the bottom but used the torpedotube for getting rid of the garbage until the plasticbag once bursted. After that the torpedo people  denied to use that procedure.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Dec , 2014, 13:49

Hello Mr. Tore and All,


My U-96 is actually in the up-stairs loft area along with my computer and flat screen TV - sort of a man cave with all my other collections and my library case of books.


Dougie, I have learned a lot in the past year about U-Boats from Mr. Tore, and I would NOT put too much faith in those past Subcommittee SCR articles.  My knowledge back then came from what little I could find in books and on internet.  I discovered early on that even some of the German sites has bad information!


I wish I had finished my OTW U-96 with a WTC, but it's been a display model for the past 10 years (my how time flies!).  I can't pry the hull apart to install the OTW wtc like Jeffrey LaRue does with his model of U-552 because I built the hull with a few internal ribs to get the hull shape correct.  I guess I could cut the aft section off like is done with the Engel type VIIC model.


It's OK for now...  I have two official photos from the French Naval Museum of the Brest U-Boat Pen taken after it was liberated by the US Blue and Grey Division framed above my U-96, and a piece of concrete from the Pen when it was bombed by the RAF during WWII in a Gold Shadow Box.  I guess like U-995, my U-96 has become a museum boat...


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Dec , 2014, 22:06
Hello Mr Tore(?) and Maciek.


Mr Tore, my wife Maureen said I was to call you "Your Excellency" since you are the Ambassador for Norway to 9 states in Africa.  She is very familiar with the correct state protocols because before she married me 22 years ago; she was the secretary to the Moroccan Ambassador in Jakarta, Indonesia. Apparently, this Chinese lady lowered her standards to marry an older (14 years) American computer engineer.


Maciek, thank you for the information on the TDC.  I updated Skizzenbuch and the latest version is in dropbox.  I updated pages 367 and 375 that had some wrong information about charging the batteries.  I hope I got it right this time.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2014, 02:20
Don.
I don't`think I deserve that title, but here I am called the Father of Her Excellency, which implies some benefits. Realising you are married to a Chinese, I can mention I worked with the China mainland Shipyards for some 10 years and over there I was called Nie Ha. Nevertheless I prefer my VIIC title, the Chief.
Approaching the season I would like to send all my friends on this thread greetings from a Norwegian, spending his Xmas in rather unusual environment, under tropical condition almost on the equator in Central West Africa.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2014, 14:28
Mark.
Your question on the location of the magnet compass projector.
 Down below is an image of the compass projector in the control room just above the helmsmans position. The red circle indicates the missing removable Anschutz gyro repeater.
The other image shows the two different magnet compass casing executions on the casing deck up front of the conningtower casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Jan , 2015, 20:03
Hello Mr. Tore and Maciek,


First of all, I want to wish all a great and prosperous New Year 2015!  I have been working on Skizzenbuch for over a year and I have come to the conclusion that most of the words were written by Mr. Tore or Maciek.  I just happen to be a editor who has assembled everything with graphics into Skizzenbuch that looks good to me.  Skizzenbuch was an original project for me to learn how the Type VIIC U-Boat worked and to have a printable document for my own personal library.  What happens now - we shall see?


I have uploaded the latest version of Skizzenbuch into dropbox with updated documentation to the "Torpedo Section."


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2015, 01:59
Don.
A happy new year to you as well.
I like your last brush up of the Skizzenbuch very well and shall revert with a few comments later. Right now I am posting an image with details of the two pitot tubes for the speedlog which might have your interest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jan , 2015, 11:11
Maciek.
I have been asked  about the Anschutz gyro repeaters and checked with your translation of your exellent VIIC manual provided by Donald.
On page 73 is stated:
" a) Gyro compass installation.
      The Gyro compass installation consists of a gyro compass ( in the controlroom) and seven repeaters-
      The repeaters are located as follows:
      1 in the controlroom
      1 in the conningtower
      2 on the bridge ( one with bearing telescope)
      1 in the radio room
      1 wallrepeater in the controlroom near the active sonar equipment
       1 in the listening room"......

On museum U 995 the helmsmans gyrorepeater in the control room which can be moved the to emergecy steering in th E-room is missing but I cannot locate the bulkheadrepeater next to the active sonarequipment. Do you happen to have any photos showing the repeaters near the active sonar equipment, radioroom or hydrophoneroom? 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Jan , 2015, 14:22
Hi Tore,

On museum U 995 the helmsmans gyrorepeater in the control room which can be moved the to emergecy steering in th E-room is missing but I cannot locate the bulkheadrepeater next to the active sonarequipment. Do you happen to have any photos showing the repeaters near the active sonar equipment, radioroom or hydrophoneroom? 

I have never seen any photo of gyro-repeater next to the active sonar equipment (that is over chart table) in the U 995 control room. I guess, that this unit was used to replace the original helmsman repeater. However, I have attached photos of this repeater from the U 96 and U 98 control room.
The gyro-repeater in the radio room is embedded into the desk, where is integrated with the radio-direction finder dial.
I have never seen the photo of the gyro-repeater in the listening room.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2015, 04:09
Maciek.
Thank you for the photos. Scrutinising the surroundings of the chart table of U 995 I cannot find any brackets for the gyrorepeater neither the connection, it is however quite logical that the navigator would have a repeater at this table. In an emergency configuration I guess it would be logical that the helmsmans repeater was moved to the emergency steering aft as this repeater was not in use at the helmsman normal place. The navigator would still require a repeater at the chartable as the navigation continues to take place on this location in a aft steering configuration. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jan , 2015, 04:07
Don.
On page 84 in your Skizzenbuch you are using one of my images showing the wheel wrench and a wrongly assumed T bar wrench. The "T bar" shown on the casing deck is a hand support for the access in and out of the hatch  May be you should change that image and use the images below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2015, 06:55
Don.

The Junker freepiston compressor
Your Skizzenbuch contains some fragments of descriptions of the Junker which in some cases are confusing due to misunderstandings in the sources you have been using. This is quite understandable as there are very few, if any at all, complete descriptions available of this unique piece of machinery. Just after the WW2 the compressor was a topic which was widely discussed amongst  the RN and other submarine engineers as it was an advanced construction well ahead of its time, yet the beginning of the development of same started during WW1 and the first engine was shown in Leipzig 1936.
In an attempt to make a working explanation I have written the following description:

The Junker free piston compressor type 4FK-115 is an opposed piston, dieseldriven 4 stage compressor and consist of a dieselpart in in the center and two stages of compressors at the ends. The dieselengine is a single cylinder uniflow scavenged two stroke engine, having a cylinderdiameter of 115 mm and a stroke which varies normally between 218 to 225 mm. The diesel pistons are directly connected to the one- and two stage compressorpiston at the scavengingport side and a second- and third stage compressor piston at the exhaust port side.
Each piston has a yoke connected to two synchronizing gear racks driving two gearwheel with stubshaft centrally placed opposite each other on both sides of the dieselengine. The rear gearwheel stubshaft is connected to a rotary vane type cooling waterpump and by external rodconnection to a swash type of lubricator having ten supplypipes to various lubricating points, including both dieselcylinders and the four compressor cylinders.
The front gearwheel stubshaft operates a Bosch plunger fuel injection pump having its supply from the day/ setling tank in the engine room and directly connected to the cylinder fuelinjection valve.
The front stubshaft is protruding out of the compressorcasing ending in a square where a crank can be connected for moving the pistons in an outer end starting position. Around this shaft is a indicatorplate showing the position of the pistonassembly in the cylinder.
The central area surrounding the firststage compressor- and diesel enginecylinder including the scavenging ports is forming a large airbox ( light blue coloured ) which act both as a scavenging air reservoir as well as a bouncing chamber having a volume about 21 liters.

Starting procedure.
Starting is done by putting a crank on the square of the rackwheel stubshaft controlled by the synchronizing gearwheel driving the HP fuel pump. By turning the crank the pistons are forced in an outer dead end position where a hand-or pneumatic controlled catch engages and locks the piston assembly in a starting position.
By this movement the underpart of the first stage compressorpiston draws air ( light blue ) from the scavenging air inlet duct to a chamber enclosed by the underpart of the first stage compression piston and a plate with several small springloaded air supply valves ( shut at this point ) separating  the scavenging air box from the enclosed chamber under the compression piston.
App. 1/3 of the first stage compressors compression stroke acts as a part air supply ( dark green) for the air box via the compressor cylinder airports through  separate channels to the airbox.
The diesel engine is now in a locked starting position where the scavenging- and exhaustports are open, the scavenging air is pushing the exhaust out of the exhaust ports and the cylinder is filled with air from the scavenging air box.
Underneath the compressor is a starting air flask connected to the air valve assembly on the compressor front consisting of an airpressure maintaining valve which can be adjusted between 140 and 210 kg/cm safetyvalves cutting the fuelsupply when pressure is dangerously high and a startingvalve manually or automatic/pneumatic operated.
Via the starting valve, air at pressure of app 35 kg/cm2, from the startingflask is supplied to the various stages of the compressor cylinders. When the airpressure of the 1 stage reaches app. 3,5 kg/cm2, the catch releases and the pistons rapidly are forced towards each other, stopped by the compression, rate about 1:40, and the fuelinjection ignites. The combustion forces the pistons appart and by that the scavenging air is drawn into the the confined space under the first stage compressor piston  as previously explained. App. 1/3 of the first stage compressor piston stroke supplies air via separate channels to the air box to assure sufficient scavenging. The rest of the stroke supplies air to the 2nd. stage compressor cylinder. At the dead outer end of the stroke the diesel pistons reveals the scavenging and exhaustports  and air under pressure from the scavenging airbox via the scavenging ports forces the exhaust out of the exhaust ports. At this point the pistons change direction as the pistons bounce back initiated by the pressure energy of the residue airpressure kept by the adjustable outlet air pressure maintenance valve ( 140-210 kg/cm2) fitted after the  fourth stage cooler, as well as some lesser bouncing chambers formed around the compressor piston rods of stage one and two, see image. they bounce back and As The pistons shuts the exhaust and scavenging ports and the diesel compression stroke starts. At the turning of the pistons, the underside of the first stage compressor piston starts acting like a compressor, forcing air through the small springloaded valves in the separating plate into the scavenging air box and fill same with fresh air. 4/5 of the scavenging air is supplied in this way ,the remaining 1/5 is supplied by the first 1/3 of the first stage compression stroke.

Prior to the end of the diesel compression stroke the fuelpump/valve is timed to end the injection at the same piston position irrelevant of the speed ( frequency). Thus any change in amount of fuel injected is done by an earlier start of the injection.
From here on the cycles are repeated and the compressor is running.
The scavenging air consumption to produce 1 kg. of HP air (205 kg/cm2) is about 1-1.25 kg of which 0,75 kg is required for combustion, the remainder is used for purging and cooling of the dieselcylinder.
The pressure fluctuation of the scavenging air varies between 0,75- and 1,25 kg/cm2.
For a proper balancing, the compressor does not deliver air before the 4th stage air pressure reaches 52 kg/cm2 controlled by the previously mentioned air pressure maintaining valve in the starting airvalve assembly.

The length of the piston stroke  is not restricted, but as the Junker compressor is a so called fixed output machine, the stroke variation is limited and almost insensitive to the load. F. inst the speed increases only slightly as the counterpressure increases.

The compressor is fully balanced, has a low weight/volume output ratio, is not hampered so much under throttled condition which all makes it very suitable for submarines. However it is noisy and susceptible to bad combustion as carbon might be formed at the dieselpistons creating unbalance hence requires frequent maintenance intervals.

The cooling
The watercooling ( green ) is normally carried out by the vane type cooling waterpump driven from an eccentric at the back side synchronizing stubshaft  The compressor is, with exception of the 4 th. stage, only partially waterjacketed ( green coloured). The major air cooling takes place outside at the bottom of the compressor for each stage in separate intercoolers which reduces the temperature after each stage and at the outlet of 4 th stage has an endcooler for the final cooling.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jan , 2015, 23:50
Hello Mr. Tore,


I will work on updating Skizzenbuch this weekend...  I spent the last 2 days recovering a corrupted MS word file (the 3rd segment of 3 files)) that I use to build Skizzenbuch into one PDF file.  I was working on the 'Torpedo Topic" and MS Word "BLEW UP!" How poetic is that!  MY MS Word file got hit by a LUT torpedo with the correct gyro-angle, distance, bend, and search pattern using the correct a + 1a, and the a - 1a values...  Go figure.......


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2015, 01:05
Hello Mr. Tore and Maciek,


I just added all the suggested info from Mr. Tore, and I updated the torpedo section and moved pages around to make it flow better.  If there are any issues, then please let me know.  I uploaded the latest version of Skizzenbuch to dropbox...


Mr. Tore, I had to Google "Bouncing Chamber" to see what you were talking about.  I learned something new...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jan , 2015, 12:43
Don.
I have read your update on the the Junker in the Skizzenbuch and have some small remarks. The first is that RN stands for Royal navy and is primarily the British navy, the Norwegian navy is nominated as R Nor. navy, but the Junker was discussed in both navies as well as others.
 An interesting note is your translation of the German text on the Junker exhaust system where your translation says a watertrap was introduced in both end for one boat. If you look at my plate 13 images  below,   for the system for the MAN engine plate 13 A there is no such trap indicated, whereas on plate 13 for the GW engine a watertrap is introduced right before the exhaust outlet of the Junker. Unfortunately nothing is shown on the museum U 995 but I would assume any requirement for a watertrap would not depend on the type of main engine. My guess is, this has something to do with the time for updating the sketches and that the GW ME system is the latest corrected, It would be interesting to see your German text as the translation is a bit unclear to me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2015, 16:57
Hello Mr. Tore,


I corrected the RN as (Royal Navy - British)...



This wasn't my translation...  Please see *Reply #2293 on:[/size] 24 Oct , 2014, 03:08 » [/color]
[/size][/color]
[/size]This was a posting from Maciek.  Do I need to change something?[/color]
[/size][/color]
[/size]Regards,[/color]
[/size]Don_[/color]
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2015, 03:35
Don.
I have read Maciecks original German text on the Junker exhaust waterintrusion problem and believe I have an understanding of the German final solution, which eventually would be found on the boats assumed delivered after 1942.
 In 1941 they obviously still were working on the problem, then according to the documentation furnished by Maciek, they redesigned a detail on the Junker scavenging system by introducing scavenging ports on the first stage compressor stroke.
 At the outer stroke the dieselpistons reveals the dieselcylinders scavenging ports as well as the exhaust ports and the overpressure left from the combustion and airbox pushes the gases out of the cylinder against the counterpressure in the exhaust line. If the sea swell fills the exhaustpipe, the counterpressure can be excessive and water intrusion occurs. The greater the swell, the higher the exhaustpressure rises, hence a limitation to the swell of 5. To overcome the extra pressure, the  first stage compressor piston is used to give a higher scavengingpressure. This happens just when the pressure in the scavenging airbox drops as the exhaust ports are open . See my image, blue indicates the scavenging air box, (green) indicates the supportpressure deriving from the ports and separate channels from 1.rst stage 1/3 stroke of the compressors piston to the scavenging air box
 In addition I assume  a second exhaustvalve was introduced outside the pressurehull which has a airconnection on the waterside,to blow the exhaustpipe between the valve and the muffler and operated from inside the pressurehull, with interlock to the aft buoyancy ventvalve as previously discussed. See my sketch below.
 As a final countermeasure a watertrap was fitted just before the Junker exhaust outlet as indicated on the system image  plate 13 for the GW. engines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2015, 10:26
Don.
Your Googled explanation of a bouncing chamber is probably not so easy to understand in relation to a free opposed piston dieselengine. In an attempt to avoid math. and thermodynamics a very simplified explanation could perhaps be : In a conventional dieselengine the mass energy stored in the piston, conrods, crankshaft and flywheel contribute to the compression stroke. A free piston engine has no rotating mass energy stored and as there are no mechanical restrictions of the piston stroke the pistons are stopped in the outer position by aircompression. As some of the compression energy is used to fill the airvessels, part of the bouncing effect is gone. However the pressure maintenance valve keep the compression pistons backpressure at a level which gives a bouncing effect and in addition you have two small bouncing chambers (red on the image below) formed around the first and second stage compressor pistonrods. The bouncing substitutes the rotating masses and create a spring effect bouncing the dieselpistons back to compression.
 You may say it is almost the " flywheel" of a free piston engine

The green text to be inserted and the old text to be deleted


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jan , 2015, 19:22
Hello Mr. Tore,


I added two pages of info in the JUnkers section of Skizzenbuck and re-indexed the book.  I uploaded the latest version of Skizzenbuch into dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jan , 2015, 06:44
Don.
 I have read you update on the Junker based on my last info and guess it is OK. One remark, on page 93 the text says:"...the interlock prevents the Junker compressor from starting because the exhaust valve can not be opened unless the stern buoyancy tank vent valve is shut..." Maybe a simpler way to say this is: the inter lock prevent the compressor to be started as the exhaustvalve cannot be opened unless the stern buoyancy vent valve is shut, thereby keeping........"
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jan , 2015, 04:48
Don.
Reading my description of the Junker i am not fully satisfied particularly concerning the so called bouncing chamber or more correctly scavenging air box ( chamber). I have  changed some of my text in reply 2450. The old text coloured red should be deleted and the new text coloured green to be inserted. Further the image of Junker last 7-1 following the text should be deleted and the image below to be inserted. Sorry about this, but I guess this is a more correct version of the Junker. I am correcting some of the text in my reply 2456 as well soonest.
Sorry about this.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jan , 2015, 21:59
Hello Mr. Tore,


I believe I got everything corrected in Skizzenbuch in the Junkers section.  It sure is hard to distinguish the green text, but I think I got it right...  I uploaded the latest version of Skizzenbuch to dropbox for your review.  Thanks again for the corrections, and that's not a problem for me to make corrections because I want to get it right.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jan , 2015, 03:29
Don.
I had a look through the Junker part of the Skizzenbuch 13 and may be we are going into too many details as it is always something which has to be adjusted or corrected. On page 90 first paragraph of the description the correct text should be... The dieselpistons are directly connected to the first and fourth stage compressorpiston at the scavenging ports side.....
Page 91 starting procedure.... Approximately (appr)..somehow you got bold letters on several places.
             3 rd lowest line ... first-  should be f. inst.
Page 93 drawing of the bouncing chamber. The arrangement of the first stage compressor cylinder scavenging air outlet ports. On the crossection drawing you see on one side the port, on the other side is a chamber wrongly coloured green. This is in fact a channel belt covering the ports going around the cylinder and should be coloured the same way as the scavenging air box.
In addition the image of the first 1/3 of the first stage compressor stroke shows wrongly a green stripe ( scavenging air) right thru the piston assembly
If you use the two images below as a substitute for the two in your book you should be OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jan , 2015, 12:17
Hello Mr. Tore,


what is "f. inst" abbreviation stand for?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jan , 2015, 12:35
Don
For instant.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jan , 2015, 16:49
Hello Mr. Tore,


I changed over the two images and I believe I have made all the suggested changes,,.  I uploaded the latest version of Skizzenbuch into dropbox.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2015, 03:36
Don.
I checked the last changes in your Skizzenbuch and it seems OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Feb , 2015, 00:26
Hello Mr. Tore and Maciek,


My write-up on the torpedo section states the torpedo tubes were vented into the pressure hull when the torpedo launch piston was pushed back by the sea water during a submerged launch.  However, a colleague of mine indicates the blisters on the front side of the hull were vents for the torpedo tubes. 


My question:  Did the early type VII U-Boats vent the torpedo tubes externally?  If so, did this not defeat the purpose of the piston to eliminate air from escaping and expose the U-Boat's location after a torpedo launch?


See Photo...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Feb , 2015, 03:31
Don.
As you know I am not a torpedoman and Maciek is much better in giving you an explanation of the system. All our VII Cs had these "blisters".  I post some images showing KNM Kaura ex. U 995 in drydock in 1954 being a VIIC/41 ( 1943) Appart from the conningtower pretty much as the original shape. Further in her 1962 shape and lifted by a crane in Kiel approximately 1970 as delivered from Norway. Finally as museum boat at Laboe 1972. You clearly see the "blisters) on the two first images whereas they are removed on the museum boat.
In 1953 we tested a surface torpedolaunch ( with a dummy torpedo) just outside the submarine pen in Trondheim I took a picture of the event as posted.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: uboatfan on 01 Feb , 2015, 10:36
Hello togehter,

some years ago they was another discussion about these marks on the hull: http://models.rokket.biz/index.php?topic=221.0 (http://models.rokket.biz/index.php?topic=221.0)

From my point of view these marks are not related to the torpedo system.

These "bumps" have a very simple work to do: They helps to get out the huge amount of water inside the free flooded structure.
This water at this position was a big problem out at sea. Water at this position results to a hard working boat.
This problem occurs first at Type I. Later also on Type VII A. They try to fix it by many different changes of the first flooding holes. At some pictures of U35 you can see that they have also opend additional flood holes just at the position of the "bums" of later Types. This helps to get out the water. But also the water could fast get in.
At development of type VII B they ad these "bumps". This are just open flood holes. But at speed foreward the water could easy get out but nothing or only slow get in.
If someone owns a smal boat he maybe used a very similar thing to get out the water. In german it calls "Selbstlenzer".

Regards,

Uboatfan

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 Feb , 2015, 14:18
Hi Don,

My write-up on the torpedo section states the torpedo tubes were vented into the pressure hull when the torpedo launch piston was pushed back by the sea water during a submerged launch.  However, a colleague of mine indicates the blisters on the front side of the hull were vents for the torpedo tubes. 


My question:  Did the early type VII U-Boats vent the torpedo tubes externally?  If so, did this not defeat the purpose of the piston to eliminate air from escaping and expose the U-Boat's location after a torpedo launch?

I also think, that these blisters are not related with the torpedo tubes (or venting the tubes).
On the u-historia.com site (unfortunately it is not working now) some time ago they published description, that this blisters were responsible for releasing the pressure inside the tube (caused by forward movement of the boat), when the muzzle doors were opened. This higher pressure had to influence for the depth-keeping apparatus of the torpedoes.

This blisters seems to be located near the breech doors of the tubes. However, when I was visiting U995 museum, I was looking for any connections passing the pressure hull in this area. I have found nothing.

So I guess that description is quite accurate:

These "bumps" have a very simple work to do: They helps to get out the huge amount of water inside the free flooded structure.
This water at this position was a big problem out at sea. Water at this position results to a hard working boat.
This problem occurs first at Type I. Later also on Type VII A. They try to fix it by many different changes of the first flooding holes. At some pictures of U35 you can see that they have also opend additional flood holes just at the position of the "bums" of later Types. This helps to get out the water. But also the water could fast get in.
At development of type VII B they ad these "bumps". This are just open flood holes. But at speed foreward the water could easy get out but nothing or only slow get in.
If someone owns a smal boat he maybe used a very similar thing to get out the water. In german it calls "Selbstlenzer".

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2015, 01:01
I am fully in agreement with Maciek and uboatfan, I can not find any system sketches showing pressurehull passages related to the "blisters" for the torpedo systems. I believe there are some void spaces in the joint between the casing and pressurehull difficult to drain/vent. The "blisters" would possibly be ejectors drainers creating a suction as the boat moves forward and improve the flooding while diving. I never pounded upon these " blisters" but have seen many  people discussing same as a torpedo venting device. Allthough not very involved in the the torpedo system,I remember while launching the torpedoes submerged we always felt it on the ears due to inboard venting.  On the image below I have tried to show the system by superimposing  a couple of sketches.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Feb , 2015, 01:49
Hi Gentlemen,

On the u-historia.com site (unfortunately it is not working now) some time ago they published description, that this blisters were responsible for releasing the pressure inside the tube (caused by forward movement of the boat), when the muzzle doors were opened. This higher pressure had to influence for the depth-keeping apparatus of the torpedoes.

The u-historia.com website is online, the problems with the connections are on my side.
Anyway, the description I was talking about can be found here:
http://u-historia.com/uhistoria/tecnico/visitaguiada/tlt/tlt.htm (http://u-historia.com/uhistoria/tecnico/visitaguiada/tlt/tlt.htm)
in the paragraph labelled as "Comunication exterior".

However, as I said before, I do not agree with it. One drawing presents the hull valve located in the forward torpedo room, at port side, near the breech doors of the torpedo tubes. It is valve used to flood the compensating tanks and to equalize the pressure in the torpedo tubes before opening the muzzle doors. It was discussed on this forum in this topic:
http://models.rokket.biz/index.php?topic=877.msg12687#msg12687 (http://models.rokket.biz/index.php?topic=877.msg12687#msg12687)
The image below, at left presents the equalizing valves, which are described here:
http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats (http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats)
(paragraph "2. Torpedo tube flooding and drainage installation")

I can not say nothing about the valve on the right drawing.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: uboatfan on 02 Feb , 2015, 08:54
Hello together,

The picture at U-historia about the valve is completly wrong! If that valve is only located on port side why all boats have these blisters, bumps or markings on both side?
The real hull opening for this valve is visible just near to that. I have made a modification to a similar picture to show what i mean.
Second question is wy did only type VII subs have these blisters, bumps or markings?
If they are related to the torpedo system in any way: Show me equivalent openings at aft torpedo tubes or at any other german sub! You will never find something...

So (after thinking a long time about this issue) the only logical solution is that these things are a special solution only for Type VII subs.

And finaly you will find at many other geman subs very similar solutions for the same problem.
By the way: Some type IX subs have very similar bumps at front and rear!

A question to Tore:
You have made an very interesting superimposing! Could you post the complete picture of that sub? Or tell me where to find.
On this picture it looks like that these blisters are not there. I see complete open flood holes instead!
Is this sub a early Type VII B?

Regards,

Uboatfan
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 02 Feb , 2015, 10:26
At development of type VII B they ad these "bumps". This are just open flood holes. But at speed foreward the water could easy get out but nothing or only slow get in.
If someone owns a smal boat he maybe used a very similar thing to get out the water. In german it calls "Selbstlenzer".


I think the Selbstlenzer was invented after WWII by Paul Elvstrøm (born 1928) 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: uboatfan on 02 Feb , 2015, 10:52
Hi VIC20,

that is absolute correct. The Selbstlenzer was invated after WWII.
The basic funktion is similar.
The Selbstlenzer mostly had a additional valve and was foldable to get a smooth hull for more speed.

Regards,

Uboatfan


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2015, 12:29
Ejector drainer VIIC.
I believe the ejector drainer is built upon a well known principle and used in naval engineering. The system was frequent used during WW2 as damage control pumping where steam ejector pumps could handle large quantity of water. In order to try to explain the reason for the position of the ejector drain ( and flood gate) I made the image below showing the horizontal crosssection of a VIIC about the level between the upper and lower torpedotubes. The pink colour indicates the MBT 5 and the blue the difficult and narrow void space between the casing and the pressurehull. When the submarine speeds ahead there shall be a suctioneffect in the "nozzle blister" draining the void difficult space. The ejectorblistesr seems to be located at the same draftlevel as the floodgates for the bow buoyancy tank. For a submarine not having a double hull I guess the VIIC has fewer flood gates than the conventional submarines of other navies  during WW2. I am posting an image of a RN WW2 S class (having 6 torpedotubes and not double hull) being only slightly smaller than VIIC,  showing the floodgates.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Feb , 2015, 22:51
Hello Mr. Tore and Maciek,


Great job Mr. Tore!  I updated Skizzenbuch on page 85 with the "Blister" information and added 2 pages to the torpedo section.  Just a little info on charging the batteries in the G7e torpedo with photos provided by Maciek.  I uploaded the latest version of Skizzenbuch into Dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Feb , 2015, 23:33
Uboatfan.
You shall find the relevant drawings on the pages of U-Historia. Tecnica, Visita Guida, Construccion. You`ll find the link in the last post from Maciek.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2015, 00:58
Don.
I checked your to days Skizzenbuch page 85 and have following minor remarks. I don`t think you are meaning the Uboats were cursing on the surface ;D . May be you should add that the drain ejectors are situated at about the same draftlevel as the bow buoyancy floodgates. As an example of floodgates on other navies WW2 subs floodgates in the area I posted a photo of me diving in the oldfashioned WW2 equipment near the bow of a RN T class WW2 sub. clearly illustrating the ample floodgates in the area.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: uboatfan on 03 Feb , 2015, 01:14
Hello,

Tore explained exactly what i mean. Great job. Thank you. Al the jears i thougt about this blisters an their real funktion. Now the riddle is solved...

I always read about a Skizzenbuch.
Where can i find this?

Regards,

Uboatfan
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2015, 01:54
The Skizzenbuch is in currently made by Don Prince who seeks advises on this tread. I don`t think the book is completed as yet and I don`t know what Dons final intentions are, but in the last year it has increased in volume and is right now a book of 432 pages on the VIIC. Don is one of the VIIC enthusiasts who collects all sorts of info on the matter as you can see on this thread. I am merely a consultant being a very old submariner and ex. EO of KNM Kaura ex U 995 and KNM Kya ex U 926 in the 50 ties.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Feb , 2015, 11:46
Hello Mr. Tore,


Very interesting...  So you served on U-995 VIIC/41 and U-926 VIIC; I believe U-926 was scrapped in 1962.  Did you serve an any of the later subs like the Ula Class jointly developed by Norway and Germany (U-Boot Klasse 210 - Diesel-electric)?  Others?

PS: Yes I can see where the blisters align with the flood gates.  If the U-Boat is submerged, then the entire bow free flood area would be flooded.  The blisters would allow a small amount of water to flow through the bow free flood area, but that wouldn't affect the drive performance. Would it?


When running on the surface, water from the flood gate will flow up over the rounded bow pressure hull approaching the level of the lower set of limber holes in the U-Boat outer side casing.  I thought the function of the blisters was to evacuate the water.  If water was allowed to pool in this area, then it would result in a slight increase in bow weight.  At that distance from the center of gravity it only takes a little weight to lower the bow, and with a lower bow the U-Boat will require more power to maintain a set speed.


Of Course, I could be off on a tangent again... Please advise!

Note* The photo you posted of U-995 demonstrating the alignment of the flood gate and the blisters, the U-Boat looks to be running very high in the water.  The flood gate and the upper torpedo tubes look to be out of the water (the waterline is way above the surface).  Is this an unusual running condition?Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2015, 14:05
Don.
I am an old submarinefart who never served on any of the submarines built after WW2. The Ula class building programme was under the supervising of my CO on KNM Kaura (ex U 995) as well as KNM Kya ( ex U 926 )and we both served together these submarines when they were  operated as frontline subs.
I believe you are basically right in your assumption . However the blister ejector effect is depending upon the forward speed, in addition you have the buoyancy tank and later the Atlantic bow with the flare effect, all contributing to lift the bow pitching in bad weather.
We have almost exclusively been discussing the draining of the void spaces, but an other important detail is to flood the void spaces in a way that no air is trapped in the difficult areas.The blistergates would improve the flooding of the difficult void spaces as well preventing a treacherous track of airbubbles.

The photo showing the uboat bow buoyancy floodgates and the blisters  is in an extreme shallow draft condition I should think the boat is possibly without batteries, normally the buoyancy tank floodgates and the blister is just below the waterline.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Feb , 2015, 18:19
Hello Mr. Tore,


I have uploaded the latest version of Skizzenbuch to dropbox.  This version contains the corrected info per Maciek with regards to the Switchboards and updated info to the two Switchboad panels; Rotary and Toggle blade.  I found this issue when reviewing the panel drawings from the U-boot Museum schematic documentation (i.e., the accelerating contactor).  I also removed the extensive word capitalization in the text on my part; that was to make it easy for me to identify what was being covered on a page.


If you see any problems, then please advise.  Maciek will be back next week and he can verify the switchboard identification info to see if I finally got it right!  I was really struggling with the concept... 


This has been a long educational process for me and I really appreciate your and Maciek's help along the way.  After I get your and Maciek's approval, then I will commit the Skizzenbuch.pdf to a printed copy for my Leather covered post binder.  That was my original goal when I started my Skizzenbuch project; to have a book that explains how a Type VIIC U-Boat actually worked.


I have 3 different publishing companies who have downloaded the final version and it may actually become a real book.  However, I am not optimistic about this prospect because I would be an unknown author, but there is nothing like Skizzenbuck offered to the public or a U-Boat enthusiast.  So. we'll see...


One additional benefit is that I have two great friends who are experts on U-Boats!  Perhaps, I may consider another Skizzenbuch based on the Type IX U-Boat.  However, I need a break for awhile before I consider another project.   


Kind regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Feb , 2015, 01:21
Don.
Having a brief check on your final Skizzenbuch I discovered a small mistake on the crossection drawing of the Junker compressor, the 1. stage compressor inlet chamber is not marked properly, only the scavenging air inlet. As this might be confusing for the reader who wants to go into details I recommend to correct this. The compressor atmospheric air inlet is via a common airfilter as indicated, however it is branched off in two inlet , one for the diesel part and one for the first stage compressor part. I have updated the drawings on page 90 and 95 accordingly as per my images below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Feb , 2015, 18:37
Hello Mr. Tore,


Thank you for the updated info...



On Page 95, I cut the old drawing and pasted the new Junkers exhaust.jpg in; not a problem...


On Page 90 I copied the changes over from Junkers exhaust b.jpg onto the existing drawing because I liked showing the cylinders and the bouncing chambers in two different positions.  If I just added the Junkers exhaust b.jpg to Skizzenbuch as another page, then I would have to add a 2nd page to sync up the rest of the book because the schematic Plates need to be on a odd page number; re-do the page numbers and the index... I would like to avoid that if at all possible.


Please let me know if what I have done meets with your approval?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2015, 00:20
Don.
Your copies are OK. Note the crossection drawing is of a Japanese  Junker made under license by Kohama and used for Japanese submarines during WW2, however they are basically the same.   One thing strikes me though, the opposed pistons on the Junker compressor have deep recesses located near the piston crowns which can be confusing on the drawing with regards to the scavenging chamber.  These recesses are simply access recesses to the fixingnuts for the pistoncrowns and have as such nothing to do with the scavenging chamber, see my sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Feb , 2015, 11:59
Hello Mr. Tore,


The is interesting, as to how the piston crown was attached to the Compressor 1st and 2nd stage.  I don't believe I want to go that deep into the Junkers compressor in Skizzenbuch.  However, for my own knowledge this access looks like a means to disconnect the piston crown from the compressor's first two stages.  The piston crown burning and carbon deposits were a maintenance issue.  Just how far did the mechanic have to go in tearing down the Junkers compressor to remove and clean or replace the piston crowns?


Regards,
Don_







Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Feb , 2015, 12:19
Hello Mr. Tore,


One more question about the Junkers Compressor...  Did it have a piston sleeve to protect from wearing out the compressor casting?



That brings up an off-topic interesting question...  Junkers licensed Kohama to build the U-Boat compressor; were companies bound by International Law to respect the copyright laws even though the countries were at war?  Could the U.S. Department of Defense tell General Electric to build the compressor for American submarines; besides the Russians had stolen the Atom Bomb secrets from the U.S.?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2015, 14:28
Don.
I believe Kohama was a Japanese professor involved in the technique and that the licence was sold by Junkers to Kobe steel as an ordinary business agreement before the war.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2015, 14:48
Don.
The Junker dieselpiston crowns were attached to the 1. and 4. stage compressor piston on one side and 2. and 3. stage piston on the other side. As the diesel piston crowns are in direct contact with the combustion and as such are exposed to substantially higher temperatures than the compression pistons they have to be of another alloy hence the separate pistoncrowns. For normal maintenance you did not have to disconnect the pistoncrowns. However the freepiston compressor was very susceptible to carbon deposit due to balancing. A clean Junker compressor could hang in a wire and run with not much movement, but in excess of 50 grammes unbalance would be almost useless as far as I remember. The piston have normal pistonrings a total of 4 and not sleeves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Feb , 2015, 23:51
Don.
Your question on "piston sleeve". As you might know the conventional engines have conrods and crankshaft which create sideforces on the cylinder walls by the combustionforces on the piston. Smaller (and lower) engines are designed as trunk engines where these forces are distributed to the cylinderwall by the so called pistonskirts of the trunkpiston. On larger diesels  as large bore mainengines for ships, you have cross headengines where the sideforces are absorbed by the separate lubricated crosshead being a slide (shoe) outside the combustion cylinder and where the conrod is connected. However on a freepiston engine having no conrod and crankshaft there are no combustion sideforces. This is the big advantage of a freepiston engine, you avoid the friction of the side forces and the rotating parts, the elimination of the friction creates a higher mechanical efficiency and a more compact engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Feb , 2015, 23:53
Don.
Following up my post of February 19Th I am posting an image  below showing the air inlets to both the 1st. stage compressor and the combusting / scavenging air intake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Feb , 2015, 21:56
Hello Mr. Tore,


The drawing does not match up well with the photo.  The savaging air filter looks to be attached to a cast manifold.  I guess the cast manifold could wrap around the back and make the connection at the bottom. The drawings indicate the savaging air intake is on the lower part of the compressor 1st stage.


In the photo there are two lines that are attached at the top; one on the forward casting air inlet 4th stage, and the other one is on the compressor 1st stage the 1st stage air outlet (or a cooling water outlet)?  Your bottom arrow is pointing to the 1st stage compressor air inlet which is at the casting location but internal beyond the 4th stage casting???


I believe the line near the red arrow is the cooling waterline to the 4th stage, and the smaller line goes to a pressure gauge (4th stage pressure?)....


How wrong am I...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2015, 08:45
Don.
No, it does not match as the sketch is possibly made by the Kobe people and differ slightly from the Junker installed in the VII Cs. It was the best I had for showing the working principle of the Junker compressor.
I have made an image of the Junker installed in U-995 and making reference to the Kobe steel drawing for localizing the various pipes. You`ll see I have removed the scavenging inlet port and the first stage inlet as they don`t match the Kobe steel execution. I assume it is hard to localise the 1 stage outlet pipe and guess it could be a pipe underneath the compressor entering the 1. stage cooler situated under the compressor and placed at the casing at the same distance from the left end as the coolingwater entrance.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Feb , 2015, 16:46
Hello Mr. Tore,


I'm not too concerned about the differences in the junkers compressor as such.  If you look at the Junkers compressor that was installed in U-570; it looks very different as well...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 28 Feb , 2015, 01:23
Hi Tore,

I have a question about the antennas (please see the two attached pictures) of the conning tower. If you see my red circles and arrows you know what I mean. My question now, is this the accurate late war style to connect the antennas with the conning tower of a (late) typseven/41?

Thanks in advance

Falo

P.S.: I have caught the two pics from my photo report thread about U995, there are also some more conning tower pictures where you can see the antennas from a different angle if necessary for you.
http://models.rokket.biz/index.php?topic=1150.0 (http://models.rokket.biz/index.php?topic=1150.0)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Feb , 2015, 10:31
Falo.
I am really not fully conversant on this matter, but to me the museums U-995 antenna arrangement seems a bit odd. I know there were different solution, but to my knowledge the most common arrangement would be to let the antenna enter a steelpipe into the wintergarten  on the later VIICs and on the aft conning towerplatform on the earlier. Posting a few photos including one of KNM Kaura to illustrate what I mean.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Feb , 2015, 12:45
Hi Tore

Here something I am sure you have see before ;D

http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7 (http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7)

Some great detail photo's

(http://i.ebayimg.com/t/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/00/s/MTU5MVgxNDc0/z/VikAAOSwBahU4LC7/$_57.JPG)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 28 Feb , 2015, 13:01
Hi Tore, thanks for the quick information and the pictures. By seeing them now the U995 antenna solution looks really a little bit odd.


Thanks again and regards
Falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 Feb , 2015, 13:07
Hi Tore

Here something I am sure you have see before ;D

http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7 (http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7)

Some great detail photo's

(http://i.ebayimg.com/t/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/00/s/MTU5MVgxNDc0/z/VikAAOSwBahU4LC7/$_57.JPG)


Just 2999,-? A steal ;-)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Feb , 2015, 13:27
Hi Tore

Here something I am sure you have see before ;D

http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7 (http://www.ebay.de/itm/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/231487213511?pt=Militaria&hash=item35e5b68fc7)

Some great detail photo's

(http://i.ebayimg.com/t/U-Boot-Steuerbord-Maschinentelegraf-aus-Typ-VII-U-Boot-Bj-1944-selten-/00/s/MTU5MVgxNDc0/z/VikAAOSwBahU4LC7/$_57.JPG)


Just 2999,-? A steal ;-)

(https://farm9.staticflickr.com/8663/16487628460_6d69f685f4_o.jpg)

OK, it look to me if we all put in $5 for the next 20 years, we should be able to build our own Type VII.
 
All we need to know who has the biggest backyard and how near is it to the sea  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 28 Feb , 2015, 14:32
 ;D ;D ;D ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 Feb , 2015, 19:22

(https://farm9.staticflickr.com/8663/16487628460_6d69f685f4_o.jpg)

OK, it look to me if we all put in $5 for the next 20 years, we should be able to build our own Type VII.
 
All we need to know who has the biggest backyard and how near is it to the sea  ;D


Someone is funding his Bf-109 Replica by building each part several times and selling the spare parts on ebay.


https://www.facebook.com/pages/Arsenal-45/129889520415326


http://www.ebay.de/itm/Rumpfteil-1-oben-Messerschmitt-Bf-109-G-/400859893995

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2015, 01:34
Simon.
Your excellent photo of the original enginetelegraph revealed perhaps one of the ways they are financing the maintenance of the poor old U-995. By the prices you achieve for old original parts no wonder why the original gauges like the depthgauges has disappeared. The photo of the engine telegraph is most probably the original telegraph for stb E motor as you see the encircled field "Laden" is on the right side. Moreover it says MT (E-motor) stb. The original telegraph in the controlroom has the astern scale on the left side and no MT. In fact if you compare the enginetelegraphs both in the controlroom and E-room you may see they are on present days U-995 exchanged by new ones deviating from the originals which can be easily identified by the outer dialrim having "dents". So all the engine telegraphs have been "nicked?"and substituted by new. 4x2999,- makes app. 12.000,- Euro a lot of temptations to remove the original parts not so good for the museumsvalue.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2015, 06:39
Simon.
The engine telegraph for KNM Kaura had Norwegian text and the encircled field Laden was substituted by Diving. Otherwise astern was on both dials inboard and ahead outboard, indeed on your photograph from the control room both telegraphs are marked MT port and stb. whereas on KNM Kaura only port and stb. so it is possibly not nicked from the U-995. The strange thing is when they changed the telegraphs on the museum U-995 they made a different marking, astern marking came outboard and thus ahead inboard. I wonder why they changed the telegraphs and the ahead and astern on the dials as it is obviously wrong.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Mar , 2015, 16:23
Hello Mr. Tore,


Well, you got me involved so beware of dumb questions... There are telegraph units in the tower, in the control room, in the engine room, and in the e-room.


Q1. I don't recall seeing any on the bridge, so was the voice tubes used with a flashing light switch or a buzzer to get the engine room operator's attention?


Q2. 2 telegraph units in all places?


Q3. Did the tower and control room telegraph units send to both the engine room and the e-room telegraphs at the same time?  I see no reason to differentiate...


Q4. I believe the telegraph units were different (design and labels) for port vs starboard units?
Q5. Were there differences between tower vs control room labels?
Q6. Were there differences between engine room vs e-room labels?

Additional info: The three-position switches on the distributing boxes made possible selecting the active
orders transmitter (in the conning tower or in control room).


- position 1 - transmitter in the control room is active; transmitter in the conning tower repeats the transmitted orders


- position 2 - transmitter in the conning tower is active; transmitter in the control room repeats the transmitted orders


- position 3 - transmitter in the control room is active; transmitter in the conning tower disabled


There were additional switches on the control boxes, which made possible disabling acoustic signaling devices (bells and buzzers) in case of silent running.

kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Mar , 2015, 00:22
Don.
Q1. There are no telegraphs on the bridge. This was quite common on naval vessels at the time as they had an open bridge not only on the submarines. Orders were passed on via the tower hatch or voicepipe, depending on circumstances and weather, generally to the helmsman in the control room who operated the enginetelegraphs and normally did not pass on orders to the engineroom by voicepipes. Every time the enginetelegraph was operated, it activated both an acoustic alarm and a flashing red light in the engine room and E-room.

Q2. Every telegraph position had a separate telegraph for each shaft.

Q3. As far as I recall yes.

Q.4 The telegraphs were identical in design however as many components on a twin engine installation, in the engine room and controlroom port was a mirror execution of starboard as f.i. the astern markings were in both inboards. In the E-room I guess it was different, the starboard dial had astern on the right ( the port opposite) side thus towards aft at the switchboard maneuvering place, hence my assumption the Euro 2.999,- telegraph is possibly from the E-room.

Q.5. I don`t recall any difference.

Q.6. Same.

One final mark though, if you look at the photo of the engine telegraphs at the helmsman place in the KNM Kaura`s controlroom, you shall see a removable nameplate stating "Diesel" hanging on the nob of the port engine telegraph which means the order from the bridge is to run on diesel. On the substitute enginetelegraphs of the museum U-995 not only the dial rimring is different but there are no maneuvering knob as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Mar , 2015, 00:50
Hello Mr. Tore,


on Q1 -  I was thinking about a night surface attack where the helmsman was on the bridge controlling the rudder.  I guess they would use the voice tube to change speed.  However, the diesel engine room is noisy and in order to listen for the commands, I believe there had to be a signaling device; like a switch on the bridge to cause the lights in the engine room to flash to signal the diesel operator to check the voice tube for speed commands...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2015, 01:08
Hi Don,

on Q1 -  I was thinking about a night surface attack where the helmsman was on the bridge controlling the rudder.  I guess they would use the voice tube to change speed.  However, the diesel engine room is noisy and in order to listen for the commands, I believe there had to be a signaling device; like a switch on the bridge to cause the lights in the engine room to flash to signal the diesel operator to check the voice tube for speed commands...

helmsman took the station at the bridge only when manoeuvring in harbour. During the night surface attack, his station was in the conning tower, and he received orders verbally through the open conning tower hatch. If he was on the bridge, it would be impractical: first - there was additional person on the crowded bridge, second - during the alarm dive, there had to be steering panel detached, moved with the cable to the conning tower, there attached again. It would take too long.

So the commanding officer passed the orders related with the speed and course verbally (through the hatch or voice tube) to the helmsman in the conning tower, and he set the issued order at the machine telegraph and change the course according to the order.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2015, 03:18
Don-
Maciek put it right. In order to make the system of passing orders by voicepipes easy to understand I made the voicepipe sketch below.  It is only one voicepipe connection to the bridge. When you was cruising on surface in bad weather the top hatch was shut as the bridge was washed over by the sea which otherwise would flush down in the conningtower and controlroom . You reduced the people on the bridge to only officer of watch and an outlook. Communication was then via one voicepipe either to the conning tower and/or the control room (three locations). In the conningtower  the voicepipe orders could be passed on by separate voicepipes, (violet) to the controlroom, radio room and sonar room, the green to the CO., the yellow to control room and forward torpedoroom, blue to control room and aft torpedoroom. It is obvious that you could communicate to the same places from the controlroom as the conningtower, however in addition there was a voicepipes connection  pink to the aft torpedo room.
It might be of interrest to include the voicepipes in your Skizzenbuch as it clearly shows the system of ordercommunications
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2015, 04:20
Don.
Your question referring to night attacks made me remembering a scene of the outstanding movie Das Boot. If you remember after the sinking of a tanker you have spectacular view of the burning tanker observed by not less than eighth people on the bridge. As far as I remember the movie should reflect on a situation in October 1941. The Royal Navy did a lot of efforts to develop counter attacks of the wolfpack tactics in the early forties. A very important element was the development of a naval 10 cm. radar for observing surfaced submarines. I guess a first test was made as early as 1938. The equipment got a priority for use on the convoy escort vessels and the first usable sets were installed on two corvettes April/May 1941. The other corvettes followed soon. I have my shelf served on one of these corvettes in 1948/49 with this radar which compared to to days standard was not great but usable within a range of 7000 meters. I don`t know how much the German submarine CO`s knew about this radar in October1941 but to me it seems like an incredible risk to observe this tanker surfaced with a crowded bridge of at least 8 people. I wonder where the Uboat tactic movie consultants have been.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2015, 07:32
Hi Gentlemen,

I would guess, that during the night attack, the following persons would be at the bridge:
4 lookouts, commanding officer and torpedo officer - that would be 6 persons.

Regarding to the German awareness of allied radar in October 1941, here is some document:
http://www.ibiblio.org/hyperwar/USN/rep/ASW-51/ASW-14.html (http://www.ibiblio.org/hyperwar/USN/rep/ASW-51/ASW-14.html)
where in the paragraph 14.2.1 is stated that:
Quote
From the start of World War II, the Germans were fully aware of the possibilities of meter ASV radar and had developed their own airborne search equipment, but it was not until the summer of 1942 that they concluded that the Allies were using radar for U-boat search and initiated a hurried program for the development of search receivers to detect the radiations. The first equipment to be installed on U-boats was the R-600 or Metox with a low wavelength limit of 130 cm. It was of the heterodyne type, thought to be the only type capable of sufficient sensitivity, and so it radiated energy, a property which eventually caused its abandonment. Nevertheless, it was used with apparent success, and the conditions of its introduction and use are of considerable interest.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2015, 08:18
Discussing about machine order telegraphs, I would like to mention one thing.
The type VIIC U-Boat manual (http://uboatarchive.net/Manual/Manual.htm) on page 181 describes the following item:
"Rudder order telegraph and rudder angle indicator system"

This piece of equipment is related with the emergency (hand) steering in case of main rudder electric control failure. In such situation, the helmsman took his station in the aft torpedo room, near the air compressors, at the emergency steering station. There was located the hand wheel for driving the main rudder. The helmsman took with him the detachable gyro-compass repeater, to know the current course.
As we know, the helmsman received two kinds of orders: heading order (i.e. "on course 71 deg" or "on east course") and rudder order (i.e. "hard port" or "15 degree starboard") related with the rudder angle. If the helmsman was in the aft torpedo room, the heading order was passed to him verbally. But rudder orders could be passed by means of the "Rudder order telegraph" which was coupled with the "Ruder angle indicator system".

The rudder order telegraph system consisted of (as described on page 181 of the manual) from the rudder angle indicator coupled with the rudder order transmitter located in the control room and from the rudder angle indicator coupled with the rudder order receiver located in the aft torpedo room.

Unfortunately, I have never seen any photo related with the type VIIC U-Boat, showing such system. Similarly, it can not be found on board of U995. I guess, that the simple rudder angle indicators (without rudder order transmitters and receivers) were installed due to cost/labour saving purposes.

However, such device can be observed on the board of U505. I have attached the photo "U505 main rudder order telegraph.jpg", which shows the rudder angle indicator with the rudder order transmitter. You can see two pointers (one above the other) - one showing the current rudder deflection, the second is the rudder order. Below, you can see the knob for setting the rudder order. The label at the bottom of the dial says: "Hauptrudder Telegrf Geber Lagenzeiger" that means "Main rudder order telegraph transmitter and indicator".

At the emergency steering station (in the aft torpedo room) was installed the similar unit, but without the knob.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Mar , 2015, 23:43
Hello Mr. Tore and Maciek,


I just could not let all the good info pass without updating Skizzenbuch.  I changed pages 186, 196, and 284.  I uploaded the latest version of Skizzenbuch to dropbox.  Please let me know if you approve...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2015, 02:38
Don.
I have no remarks. I cannot recall ever seen the rudder angle telegraph on any of our VIICs all commissioned after Sept. 1943. Contrary to the navigation order: steer or come to so many degrees, the rudderangle order was usually given during normal maneuvering and emergencies. Turning a small nob at the rudderangle dial seems to me to be a bit bothersome as the order was usually given verbally by the officer on watch directly to the helmsman requiring a quick action. As far as I recall we tested the emergency aft rudderoperation by using the telephone or the voicepipe port side aft of starboard main switchboard next to the emergency rudder helmsman.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Mar , 2015, 02:41
Hi Gentlemen,

I would like note one more thing, related with the rudder order telegraph/indicator.
If you look closer at this unit, you will see the label "Stromlos" at the
left edge of the dial. It is the "power failure (Stromlos) annunciator flag". When
the telegraph/indicator subsystem is powered, this flag is held by the electro-magnet
at the edge of the dial. When the power is off, the electro-magnet releases the flag,
which falls under its own weight to the dial centre. This simple system signalled the
operators, that the power is off, and the pointers are not necessary indicating the
desired values.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2015, 03:02
Don and Maciek.
In addition to the powerfailure remark from Maciek it is perhaps worth while to mention if the electric rudder angle indicator fails it is like on the hydroplanes, a mechanical ( teleflex) angle indicator at the emergency steeringcolumn as can be seen on the image below. The electrical rudderindicator is on the top aft of port main switchboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2015, 17:14
Hello Mr. Tore and Maciek,


I have many questions...


The rudder order telegraph system seems to only indicate the angle setting for the rudders and not the desired course.  For instance - submerged and a rudder electrical failure due to a depth charge attack.  If the command is 90 degrees to port, the rudder order telegraph only goes to 40 degrees (port or stb) and the manual states that maximum deflection is 35 degrees manually and 33 degrees under electrical power.  The rudder angle will determine the turning circle at which the U-Boat turns to port.  I believe the forward speed is a factor in this equation as well.


The commander gives the order for 90 degrees to port, but it looks like the helmsman would need to be trained to know what angle to set the rudders depending upon the forward speed to achieve the port 90 degree course with the greatest distance from the spot of the command.  Otherwise, if the command was "90 degrees hard to port", then the helmsman would know to apply full rudder angle.  Am I off on a tangent again?


The rudder order telegraph system doesn't seem as useful as I initially thought it would be and I can see where the cost/benefit analysis scrapped the system.  Besides, how often did the U-Boat loose electrical rudder control.  I'm inclined to thing that if the U-Boat lost electrical rudder control, then the phone to the helmsman in the Aft torpedo room would be the best line of communication.


Now for a few questions about the rudder order telegraph system...


Q1.  Once they send a rudder order say 15 degrees to the helmsman in the aft torpedo room.  Do they then sent a zero degree setting? 


Q2.  I was thinking about the control room sending a 2nd command for another 15 degree rudder change.  How do they accomplish this change so the helmsman knows this is a 2nd command?


Q3.  This system just provides the rudder angle...  How does the helmsman get the actual course command from the commander?  By voice tube, by phone, or by crewmen repeating the command?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2015, 22:28
Hello Mr. Tore,


I updated Skizzenbuch and used your photo of the Aft helmsman's station with the telephone (I like that info!)...


updated pages 183, and 196.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2015, 00:16
Don.
I don`think any responsible navigator would use the term 90 degrees rudderangle. The order would be hard port or starboard the helmsman who would keep the steeringknob down till the rudder limitswitch stops the rudder at the preset max angle. If you want to turn on a nickel you used the propellers one full ahead the other full astern. A change in sailing course could be just a new compass figure and leave it to the experienced helmsman to come to that course using an appropriate rudder angle. In the event of an inexperienced helmsman you guide him by giving rudder angle orders which could be 5 degrees to port, when the boat start turning and approaching the new course the officer of watch order midships followed by steer so-so many degrees. As  said before in an emergency to avoid a collision or as in my time a drifting mine, you immediately gave the order directly to the helmsman hard port (or starboard) in those cases I believe fiddling with an order knob on the rudderangle indicator could be a dangerous delay and voicepipe would be used.
I cannot comment on the details of the rudderangle knob as I never saw same on any of our VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Mar , 2015, 00:32
Hi Don,

The rudder order telegraph system seems to only indicate the angle setting for the rudders and not the desired course.  For instance - submerged and a rudder electrical failure due to a depth charge attack.  If the command is 90 degrees to port, the rudder order telegraph only goes to 40 degrees (port or stb) and the manual states that maximum deflection is 35 degrees manually and 33 degrees under electrical power.  The rudder angle will determine the turning circle at which the U-Boat turns to port.  I believe the forward speed is a factor in this equation as well.

The command "90 degrees to port" is related to the course directly. So if you are on the course 145 degrees, the helmsman changes the course to the 55 degrees. The rudder order telegraph was to be used only to pass the rudder deflection orders.
The course orders were to be passed verbally. So if you want to change the course from 145 degrees to "90 degrees to port" using the rudder telegraph only, you would have to set the value "30 degrees port" (for instance - it would depend how fast you want to get to the new course). The helmsman set the rudder to this value. Then, you (as the commander in the control room) are watching the gyro-compass and when the boat closes to the course 55 degrees, you gradually decrease the rudder deflection on the telegraph.

You have to remember, that helmsman at the emergency steering station had its own gyro-repeater (the unit from the control room), connected to the socket in the aft torpedo room (see the plan 16 in the Skizzenbuch you have received from Cuxhaven).

The rudder order telegraph system doesn't seem as useful as I initially thought it would be and I can see where the cost/benefit analysis scrapped the system.  Besides, how often did the U-Boat loose electrical rudder control.  I'm inclined to thing that if the U-Boat lost electrical rudder control, then the
phone to the helmsman in the Aft torpedo room would be the best line of communication.

Well, indeed it doesn't seem to be  very useful. However, I can imagine that it was designed to use in the combat, silent running conditions. The "U-Boat commander handbook" (http://archive.hnsa.org/doc/uboat/index.htm (http://archive.hnsa.org/doc/uboat/index.htm)) says, that when being pursued by enemy, the silent running order was issued. Then the all unnecessary machines were switched off and the main rudder and diving planes were controlled manually. All the voice communication had to be reduced to minimum. In such situation (while doing evasion manoeuvres) the exact course steering was less important than the relative course changes. So passing the rudder orders by telegraph (not verbally) would make sense. But these are only my assumptions.

Q1.  Once they send a rudder order say 15 degrees to the helmsman in the aft torpedo room.  Do they then sent a zero degree setting?

They set the telegraph to zero degree. Generally, helmsman had to always make the rudder angle indicator pointer follows the rudder order telegraph pointer.

Q2.  I was thinking about the control room sending a 2nd command for another 15 degree rudder change.  How do they accomplish this change so the helmsman knows this is a 2nd command?

As long the first command was issued (set to telegraph), the main rudder was deflected by this angle. So second rudder change was senseless.

Q3.  This system just provides the rudder angle...  How does the helmsman get the actual course command from the commander?  By voice tube, by phone, or by crewmen repeating the command?

All three ways could be used. I would prefer repeating by crewman chain (as it would be most silent way).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2015, 05:53
VIIC Telephones.
Puzzled by the telegraph question and the rudder angle order system adviced by Maciek, I checked the excellent manual Uboatinformation for Type VIIC , year of construction 1939 effective July 15 1940   donated by Don translated by Maciek. In chapter V the various communications are described, both acoustic, electronic and visual. Internal communication by loadspeaker is mentioned, but as far as I can see not the telephone system. Further when looking at photos of older VIICs on the locations where you have the telephones on the later VIICs, you do not find the phones as on the image below where you see a photo of der Fuehrer on the place where you should expect to see a phone. As the phones were a very important communication link I believe they definitely should be mentioned under communication in the manual, I wonder if same was not installed on the early VIICs but introduced in the later execution  and as a consequence the rudder angle order knob was removed on the late VIICs. As far as I could check U 570 ( commisioned May15.th 1941) had the voicepowered telephones installed allthough of a different design and placed partly on other places than on U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Mar , 2015, 13:02
Hello Mr. Tore and Maciek,


Thank you for all this great info...  Mr. Tore what U-Boat is that in the photo where the phone was not there?  And one question off topic just for my personal info; was there ever a instance where an Escort Destroyer was on a depth charge run against a U-Boat, and a second U-Boat in a Wolf Pack took the Eccort Destroyer out by torpedo?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Mar , 2015, 22:40
Hello Mr. Tore and Maciek,


After reading Maciek's info about the Rudder Order Telegraph system and the use in the silent running mode; I was convinced that the system was indeed a handy thing to have on-board the U-Boat.  I made the photos smaller on page 196 of Skizzenbuch, so I could add the text info provided by Maciek.  (Thank you again Maciek for my education lesson for the day!).  I placed the latest version of Skizzenbuch in dropbox...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Mar , 2015, 01:05
Hi Gentlemen,

Puzzled by the telegraph question and the rudder angle order system adviced by Maciek, I checked the excellent manual Uboatinformation for Type VIIC , year of construction 1939 effective July 15 1940   donated by Don translated by Maciek. In chapter V the various communications are described, both acoustic, electronic and visual. Internal communication by loadspeaker is mentioned, but as far as I can see not the telephone system. Further when looking at photos of older VIICs on the locations where you have the telephones on the later VIICs, you do not find the phones as on the image below where you see a photo of der Fuehrer on the place where you should expect to see a phone. As the phones were a very important communication link I believe they definitely should be mentioned under communication in the manual, I wonder if same was not installed on the early VIICs but introduced in the later execution  and as a consequence the rudder angle order knob was removed on the late VIICs. As far as I could check U 570 ( commisioned May15.th 1941) had the voicepowered telephones installed allthough of a different design and placed partly on other places than on U 995.

I was also puzzled, when I had not found description of the voice-powered telephone in the type VIIC manual. I'm sure I have been reading about it somewhere...

Indeed, in the document effective on July 15 1940, the voice-powered telephone is not mentioned. The only electrical system for passing orders was the "Broadcast and announcement system" ("Lautschprecheanlage"). As described in the manual, it consisted of the central control unit (with the amplifier) in the radio room and speakers in every U-Boat compartment. To the control unit in the radio room there can be connected a record player or radio-receiver and the music from the record or radio could be broadcast through the boat. In the same way, the microphone could be connected and the announcement could also be passed through the boat.

But this system could also be used for communicating between the battle stations. For this reason, in several  places of the boat were installed terminals for connecting the headphones and the microphones. These terminals were in the aft torpedo room, E-motor room, control room, conning tower, officers room and forward torpedo room.
On the board of U995 the terminals are visible, but unfortunately without the headsets.

This system required to be powered for operation.

Some details on this system you can find in the section "II. General Announcing System" of the type IXC Design Study (http://uboatarchive.net/Design/DesignStudiesTypeIXC.htm (http://uboatarchive.net/Design/DesignStudiesTypeIXC.htm)).


(http://uboatarchive.net/U-570/U-570Photo17.jpg)
(speaker in the control room of U570)

A Tore mentioned, the British report on U570 and his experience from KNM Kaura provide the information about second voice communication system (not present or mentioned in the 1940 manual) - the voice powered telephone.

Generally it consisted of several units located in the forward and aft torpedo room, control room and diesel engine room. In contrast to the broadcasting system, it did not require the power to operate. On the board of U995 you can see these units, but unfortunately, they are without the hand-sets. One note - the telephone unit in the forward torpedo room is not original (German war-time).

Some details on this system you can find in the section "III. Ship's Telephone Systems" of the type IXC Design Study (http://uboatarchive.net/Design/DesignStudiesTypeIXC.htm (http://uboatarchive.net/Design/DesignStudiesTypeIXC.htm)).

And one more thing - the report on U570 also mention about rudder order telegraph.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2015, 06:33
Maciek and Don.
I checked the voicepowered telephones a bit further. First of all a correction, on the photos taken by the US navy of U 570 the helmsmans place item B is marked as telephone. I don`t think this is correct, it is possibly an electrical coupling/ fusebox. The shutting handle could resemble a phone, see my image.
 I have, in my private collection, a photo of the lower part of the phone in the controlroom of KNM Kaura, taken 1954 and I believe this is the original phone. If you compare this to the phone of fwd torpedo room of U 505 provided by Maciek, I guess we can consider they are of the same type. U 505 a IXC, was commission in Aug. 1941and had the same phone as U 995 a VIIC/41. The phones on the museum U-995 is possibly not the original allthough they looks very much the same apart from the lower support for the microphone.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2015, 07:43
Don.
I see I forgot to answere your question which boat substituted the telephone with Der Fuehrer. Sorry I don`t know which Uboat the photo refers to it was a common photo on the net.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2015, 13:12
Hello Mr.Tore and Maciek,


I'm going to add 2 more pages to Skizzenbuch to include all the info on the announcement system and the phone system.  Obviously the announcement system with speakers and head sets required an A/C motor generator, so this could not be used during silent running.  However the phone system looks to be DC powered and could be used during silent running.  Am I correct about the differences?


The phone receivers had the small crank and was it to get the attention of the receiver calling location?  I believe it was a buzzer OR a physical indicator (light or what)?  I'm not sure about which....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Mar , 2015, 14:27
Hi Don,

Obviously the announcement system with speakers and head sets required an A/C motor generator, so this could not be used during silent running.

The power requirements can be seen in the type IXC design study: the amplifier was powered by 220 V AC.


However the phone system looks to be DC powered and could be used during silent running.  Am I correct about the differences?


The phone system is not powered by any external power source. The voice converted into the electric signal was not amplified in any way, the signaling (getting receiver attention) was done by hand-driven small AC generator at each unit.

The phone receivers had the small crank and was it to get the attention of the receiver calling location?  I believe it was a buzzer OR a physical indicator (light or what)?


From the design study: the buzzer for audible signal and in parallel with buzzer the visual indicator. The hand crank driven magnetic type generator, which was used to power the buzzer and visual indicator at receiver side.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2015, 19:38
Hello Mr. Tore and Maciek,


First, I would like to thank Maciek for the quick response to my questions about the phone receiver...  I uploaded the latest version of Skizzenbuch to dropbox.  I added pages 198 and 199 with the Broadcast and Announcement system, and the phone system.  Then I did the usual indexing and page number changes.  I believe Skizzenbuch is about completed for now.  Unless, of course, something else comes up where there is an information gap...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2015, 04:19
VIICs after WW2.
At the surrender 8. of May 1945 a total of 156 remainding U boats were scattered in various places, a substantial part of these were VIICs. The majorities of the uboats ended in Norway, a total of 96 consisting of various types. The three major allied countries kept some of  these boats mainly XXI for further investigation and were scrapped afterwards. The majority of the rest were destructed and sunk in operation Deadlight. However a few survived Deadlight and were in active service till early 1960. One VIIC in the French Navy and three in the Norwegian navy. One of the latter, KNM Kya ex. U-926 was modernized and got a "sail". Probably the only VIIC in this modern version. Below is an image showing KNM Kya in her old and new execution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Mar , 2015, 00:47
Hi Tore,


thank you for interesting information and pictures.
French type VIIC U-Boat Laubie (ex-U 766) was also modernized (after collision in 1950).




--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2015, 06:10
Maciek.
I was not aware of Laubies modernizing and thanks for the images. As far as I remember she was involved in collisions two times and the latest caused her to be scrapped. We had two of our submarineofficers sailing with her in the early 50- ties in order to exchange experiences in the VII Cs operation, but I don`t believe there was any cooperation in the modernising. As far as I can judge there is a big difference between the modern design of Kya and Laubie.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Mar , 2015, 20:42
Hello Mr. Tore and Maciek,


The type VII U-Boats that had the modern bridge/sail in the 50's; did that make any improvement in the maximum submerged speed?  I would think the modern sail would present less forward resistance?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Mar , 2015, 01:17
Don.
I don`t have any figures, but if you compare the tower and wintergarten on the late WW2 VII Cs with the latest modernisation of KNM Kya I think it is obvious that the drag is much less on the latter. To days sail or dorsal fin is highly streamlined as the rest of a modern submarine, but much of the functions of the VII Cs tower are removed into the controlroom and the fin is more like a bridge and a dorsal stabiliser rather than  tower . In my time we started in rebuilding the conventional wintergarten and removing the scepters, not only to reduce the drag but lower the noise submerged as well. However as you know the submerged speed of the VII Cs was not very high in any case.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Mar , 2015, 13:39
Hello Mr. Tore and Maciek,


The type VII U-Boats that had the modern bridge/sail in the 50's; did that make any improvement in the maximum submerged speed?  I would think the modern sail would present less forward resistance?


Regards,
Don_

I remember reading somewhere that someone run some Fluid dynamics software test on the Type VIIC’s. He said that most of the drag was causes by the open bridge of the Type VIIC’s and that the wintergarten had little effect on the drag.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Mar , 2015, 21:03
Hello Mr. Tore and Simon,


I found 3 drawings and 1 photo...  #1 - English, #2 - Italian (Work on the bridge of the KYA (U926). This aerodynamic conversion was suggested by von Haggstadt in 1959. #3 - Norwegian (K-class or conversion).


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2015, 01:20
Dorsal fin.
Simon I think it is correct that one of the main drags submerged is caused by the open bridge on the VIIC. Don has shared a few interesting images showing the design of the tower conversion by the Norwegian naval architect and engineer in chief of our submarine designs Kåre Hegstad ( not von Hegstadt) I knew him very well and he developed a new tower design including a telescopic schnorchel mast for our U (V) class UK built submarines in my time ( image below). Later he started to do the same with our VIICs only to finish KNM Kya before he involved himshelf in the development of a total new submarinedesign in cooperation with German designers ending up with our brand new Kobbenclass in the 60 ties which relieved our VIICs and U class.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Mar , 2015, 23:58
Hello Mr. Tore,


Do you know if Kya (U-926) ever has the updated sail/bridge modernized?  I found a photo of Kya, and it looks like someone doctored this photo to created Kya with a updated sail...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Mar , 2015, 00:37
Don.
I don`t know where you got your Kya 2 image but it is a fake. Somebody manipulated an old photo of KNM Kinn ex. U 1202 and put a dorsal fin on her, changed the pennant no. from S 308 to S 307 pretending she was the Kya, see my images below. The real fin of the modernised Kya was slightly different as she kept the hinged schnorchel in a recess in the fin.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Mar , 2015, 21:32
Hello Mr. Tore,


It's hard to understand why someone would fake information on the net like that.  I guess it takes all kinds of idiots!  I'm glad I caught it because I don't want false information in Skizzenbuch.  I updated Skizzenbuch and page 432 is about Kya and it's modified dorsal fin/sail..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2015, 01:15
Don.
I have read your last amendment to your Skizzenbuch and have a few remarks. I know there are information referring to different sources that U 926 surrendered in UK and later transferred to Norway. This is not true. Correct story is given by Aircommodore Derek Waller in his paper U boat in Norway post 8th . May 1945. U-926 surrendered in Bergen May 8th. 1945. All the 96 Uboats surrendering in Norway was soonest possible transferred to Scotland apart from 7 Uboats which were declared unfit for sea. Among these were U-995, U-1202 and U-926. The reason that U-926 was not seaworthy was they had overstressed her MBT 3 creating structural damage to the pressurehull. This damaged was caused by a mistake when blowing the tank by her own crew at the end of WW2. I have personally inspected the tank and the repair carried out. She was commissioned as our first VIIC and was an operational submarine (not training or research) 10. January 1949. She was my 2ND and last VIIC in 1954.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2015, 05:53
Don.
Further to my previous remarks on KNM Kya, your drawing showing Kya with dorsal fin is strange as it shows a port casingside of a 1942 execution on starboard side omitting the anchorbay and the correct floodgatepattern as well as the submerged exhaustoutlet. A common mistake made on several sideview drawings of the VIICs,  including the one you show is the Kingston arrangement for MBT 3. MBT 3 has three Kingstons on each side two in pairs forward and one aft. Somehow people like to make double pairs on both sides. See my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Mar , 2015, 11:04
Hello Mr. Tore,


Submerged exhaust outlet?  Was that something new?  I don't recall a exhaust outlet of that type on a type VIIC...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2015, 13:03
Don.
There are several types of exhaust outlets, I believe Simon has made a list telling which Uboat has the various outlets. As far as I remember all our VIICs had the submerged type.The image below shows the damaged U-510 having the submerged type and the KNM Kaura having same. However the museum U 995 was rebuild with the air exhaustoutlet which can be seen on the image below as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Mar , 2015, 18:14
Hello Mr. Tore,


Thank you for the info about Kya and the exhaust outlet below the water line.   I updated page 432 in Skizzenbuch and uploaded it to dropbox...
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Mar , 2015, 01:17
Don.
I have checked your last issue of the Skizzenbuch. I guess your assumption that the crew of U 926 deliberately damaged the U boat is not according to fact. In order to understand the cicumstances I shall give you a breafing. Following Hitlers suicide in April 1945 Grossadmiral Karl Dønitz, admiral of the submarines became the new Fuehrer. The situation in Germany was hopeless,but in Norway he had a full war equipped army of 300.000 men plus 87 fully equipped uboats being a considerable threat to the allies. Therefore as late as 4. May 1945 the orders from Befehlshaber der Unterseeboote (BdU )was issued:  Norway  is the headquarter of the Uboats operational control, the war goes on. It looked as if Dønitz had desperate plans to continue fighting out from Norway. On the continent scuttlings of uboats took place. (Operation rainbow), but not in Norway were everything was in control.
 The overstressing of U-926s pressurehull took place early April 1945 and at that time it would be a treason to deliberately destroy an Uboat. A fully functional Naval high command would prosecute the responsible person for such an action with deathpenalty as a consequence for the guilty people involved.  No such penalty took place so I guess the high command concluded it was an accident caused by inexeperienced crew and possibly a faulty reliefvalve causing the dammage.
Kindly note U 926 was not a sister uboat to U-995 as U-926 was a VIIC and 995 a VIIC/41.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Mar , 2015, 11:56
Hello Mr. Tore,


Perhaps a Step-Sister Ship - Once Removed?  I'm just joking of course...  Thank you for the correct information on U-926 Kya.  One question - after the repairs to the pressure hull, were there any diving depth restrictions imposed on Kya?


I uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2015, 00:23
Don.
Last update of the Skizzenbuch OK. Kya did not get any restriction as to max. diving depth officially. However we imposed unofficially testdiving to 100m nevertheless we accidentally touched the 115m mark without any problems.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Mar , 2015, 03:34
The big contrast from suddenly leaving the rough stormy surface and in a matter of seconds to be submerged in the calm quite sea was something you really had to experience to understand. This has inspired me to make paintings which I have put together in an image below, showing a 1953 fantasy situation of KNM Kaura crossing the normally rough Westfjord near Lofoten islands in Northern Norway meeting the old express steamer s/s Lofoten and underneath Kaura in a snorting mode in the same area, enclosed in the green Arctic sea. As the weather on the surface image was not suitable for snorting I "calmed" the lower image weather.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Mar , 2015, 12:39
The big contrast from suddenly leaving the rough stormy surface and in a matter of seconds to be submerged in the calm quite sea was something you really had to experience to understand. This has inspired me to make paintings which I have put together in an image below, showing a 1953 fantasy situation of KNM Kaura crossing the normally rough Westfjord near Lofoten islands in Northern Norway meeting the old express steamer s/s Lofoten and underneath Kaura in a snorting mode in the same area, enclosed in the green Arctic sea. As the weather on the surface image was not suitable for snorting I "calmed" the lower image weather.
Tore

Tore, great painting! Are they oil?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Mar , 2015, 12:46
Simon The upper is an oil my 2nd oilpainting of Kaura still a bit unfinished, the lower is a computersketch to be oilpainted later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Mar , 2015, 18:56
Hello Mr Tore,


Excellent art work; you are a man of many talents!  I updated page 426 and 427 of Skizzenbuch and uploaded it to dropbox.  I hope you approve...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2015, 01:46
Don.
You may use the painting, however as you have stretched it, the bow and tower is a bit out of proportion particularly the bow is far to pointed. As the sea is OK I have corrected the bow and tower on your stretched version, you better use this image for your Skizzenbuch. By a mistake of me, the steamer on the image is S/S Finmarken and not Lofoten.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2015, 20:10
Hello Mr. Tore,


Thank you for correcting my error (I do apologize!)...  At this point, I believe "Skizzenbuch" is finished!  I haven't made any large additions for quite awhile.  I have two publishers looking at Skizzenbuch; Pen and Sword (UK), and Schiffer Publishing (US).  I can't say for sure my Skizzenbuch will ever be published because of the format (Huge 11 x 17) and a quite unknown author (me!).  However. if the book gets published, I am obligated to send 2 copies to u-historia.com (Owner and Artist) for the use of their line drawings.  In addition, a copy will be sent to you and Maciek because I could not have written/assembled Skizzenbuch without all the help from you gentlemen!


I uploaded the latest version of Skizzenbuch into dropbox...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2015, 01:54
Don.
At the finishing point of your Skizzenbuch I wish you all the luck in your endeavour of a publishing attempt. It has become an unique book of a special topic and allthough not dealing with the interest of the masses, it would be a prime dictionary for those who shares the interest for the VIIC being by far the largest number of a submarinetype ever built.
Keep us posted.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Mar , 2015, 00:32
Hello Mr. Tore and Maciek,


Upon Maciek's suggestion, I have added 6 pages (290 - 295) to the Torpedo section about the TDC.  Maciek has done some extraordinary work on the web site http://tvre.org/en/home-page which covers all aspects of targeting.  I had to limit the info used to some general knowledge on the TDC because I didn't want the reader of Skizzenbuch to have to pull out his/her High School Trigonometry book as a reference.  However, I did point them to the web site if they want the in depth details.


I have uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Mar , 2015, 09:20
Hi Tore,

when you served on board of Norwegian submarines, did you sail on Arctic waters?

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2015, 09:27
Maciek.
Most of the time we operated north of the Artic circle and as I previously adviced we did a schnorchling test 28 days submerged from Bergen around Iceland almost to Greenland and back.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Mar , 2015, 10:01
Tore, do you remember the navigational issues? While schnorcheling for 28 days, I guess you have to dead-reckoning (no inertial navigation aids?).

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2015, 11:42
Maciek.
As you know I am not a navigator and my knowledge on the matter is limited, but I called my friend and No1 on Kaura during this schnorcheling and he told me the main tool for the navigation was the echosounder. We had very extensive charts showing fairly accurate depths in addition to detailed current data and occasional star observation. But the main navigation tool apart from the compass was the echosounder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 Mar , 2015, 15:22
Hi Tore,

As you know I am not a navigator and my knowledge on the matter is limited, but I called my friend and No1 on Kaura during this schnorcheling and he told me the main tool for the navigation was the echosounder. We had very extensive charts showing fairly accurate depths in addition to detailed current data and occasional star observation. But the main navigation tool apart from the compass was the echosounder.

Thank you very much for your answer. The occasional star observations were done through the periscope or while surfacing for a moment?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2015, 15:33
Maciek.
Very few starobservations through the navigation periscope, we never surfaced, that was a part of the test.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 Mar , 2015, 01:08
Very few starobservations through the navigation periscope, we never surfaced, that was a part of the test.

Tore, thank you for the answer.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Mar , 2015, 17:14
Hello Mr. Tore and Maciek,


I updated Skizzenbuch with the FAT hardware photos provided by Maciek in the torpedo section.  I uploaded the latest version of Skizzenbuch to dropbox...


Mr. Tore, your navigator must have had good maps and much better than the following navigator and captain in the US Nuclear submarine that hit a mountain....


The commander of the USS San Francisco, Kevin Mooney, has not been relieved of duty while the investigation of the accident continues.
Mooney could be relieved of duty if officials determine there is enough evidence that the accident could have been averted.
The investigation will look at the sub's speed, its location and whether the undersea formation was on navigational charts, officials said.
The submarine was traveling in excess of 33 knots -- about 35 mph --when its nose hit the undersea formation head-on, officials said.
The nuclear submarine docked Monday at a U.S. naval base in Guam, a spokesman with the U.S. Pacific Fleet said.
The San Francisco was escorted to port by U.S. Navy and Coast Guard vessels, according to Lt. j.g. Adam Clampitt. The submarine suffered "some external damage," he said.
"The injured sailors are being treated at a U.S. military medical facility on Guam and will be transferred to other facilities -- possibly Pearl Harbor in Hawaii or Okinawa in Japan -- as necessary," Clampitt said.
According to a military statement, the injuries included "broken bones, lacerations, bruises and a back injury."
The accident occurred about 350 miles (560 kilometers) south of Guam, the U.S. Navy said. There were 137 crew on board at the time of the accident.
Machinist Mate 2nd Class Joseph Allen Ashley, 24, of Akron, Ohio, died Sunday from injuries suffered in the accident, Clampitt said. "The Navy continues to offer its sincerest condolences and prayers to the family and friends of Petty Officer Ashley," he said.
Navy sources said the submarine was en route to Brisbane, Australia, for a port visit at the time of the accident. There was no damage to the sub's nuclear reactor, according to Clampitt.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2015, 03:01
Don
Yes, the charts were excellent don`t forget the area had been used since the viking times by Norwegian sailors and fishingmen for centuries, particularly the various heavy currents was known. You story of USS San Francisco raise an interesting question how much damage would a neutral buoyancy submarine suffer from a collision with a rock? I guess as the size of the impact would depend of the inertia massforces the speed would be the ruling factor and at to days submerged speeds in excess of 30 knots the massforces would be considerable. However the VIIC had a very modest submerged speed and in fact on one of the last WW2 missions, U-995 hit a rock. The story is: in the latter part of 1944, the German army retracted from Finland and into the northern Norwegian county of Finmark burning every town and house on their way. The Soviet troops followed and occupied the county. The Norwegian exile government in London decided to send freigthers with food supply to the population in the area and the cargo was unloaded in the incinerated town of Kirkenes. In February 1945, U-995 with Hess as the last German CO was in the area having orders to go after the allied convoys to Murmansk. Hess however decided  to attack a Norwegian freighter m/s Iddefjord laying in the harbour of the Kirkenes. Hess`idea was to approach the freighter semi submerged only the tower above the surface. Before they got in to position they hit an underwater rock shelf and got stuck at an big awkward angle, bow up. U-995 was not damaged but as she was in a fairly steep angle the was a risk of sliding astern and damage the propellers and rudders. She could not blow her tanks and surface as she would the be discovered. They waited in this position till dark and surfaced without being discovered and fired 3 torpedoes. Hess heard the detonations and recorded a sinking. However the torpedoes hit the rocks and m/s Iddefjord was undamaged as well as U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 26 Mar , 2015, 03:12
…how much damage would a neutral buoyancy submarine suffer from a collision with a rock?


(http://upload.wikimedia.org/wikipedia/commons/thumb/5/54/US_Navy_050127-N-4658L-030_The_Los_Angeles-class_fast-attack_submarine_USS_San_Francisco_%28SSN_711%29_in_dry_dock_to_assess_damage_sustained_after_running_aground_approximately_350_miles_south_of_Guam_Jan._8%2C_2005.jpg/758px-thumbnail.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2015, 03:21
Lucky they did`t have the Kursk type torpedoer ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 26 Mar , 2015, 05:15
hydrogen peroxide "fat girls"..
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2015, 07:36
Wooden dinghy/ containers.
Storage space under the casingdeck was cramped and one of the most suitable space for a non inflatable boat/raft was port side between the fwd. torpedoloading hatch and the capstan. As the torpedo loading hatch was placed off center to stb. and the pressurehull tapered, the height to the casingdeck was increased. As far as I can see this space was used for a wooden dinghy until 1943. As from 1944 there are no sign of the dinghy and the space is taken by four pressurecontainers of which the fwd. is the deepest. I assume this container was used for an inflatable dinghy which possibly substituted the wooden dinghy. U 995 did not have containers during WW2 but got 2 under Norwegian flag. She had 4 when she was restored in Germany 1970. Today the museum U 995 does not have containers. It is strange that the the Haynes workshop manual on their front page has a sketch showing a late war VIIc with 4 containers misplaced too far to the bow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Mar , 2015, 18:54
Hello Mr. Tore and Maciek,


Upon Maciek's suggestion, I have added 8 pages (426 - 434) covering the Echolot, Radio Equipment, the Listening Room, and the Radio Room. I placed the latest version of Skizzenbuck in dropbox. 


If there are any issues with the latest version, then please let me know...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2015, 00:22
Don. Echolot.
As you see from my answer to Maciek question on the echolot the equipment, it was an important instrument to be used for navigation. Today with satelite navigation and previously Decca and Loran, it is easy to forget the old important navigation system as sounding. In the age of the sailingship,  navigation in difficult water was carried out by lead and line by a man in the bow reporting to the captain. In the Northsea Channel as well as other difficult areas they covered the lead with grease or wax which made it possible to take samples of the sea bottom  to the surface.  They were able, by looking at the gravel,sand, clay or mud, to determine the position of the ship . As mentioned we had very good charts with depth contoure lines which made the echolot the most important navigation aid for submerged navigation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Mar , 2015, 15:33
Hello Mr. Tore and Maciek,


I added some information on S-Gerät and 2 photos on page 430 and uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2015, 05:38
Don.
Looking into your last Skizzenbuch I accidentally discovered a wrong detail on page 416. On the Schnorchelmast you have used one of Simons old drawings which shows the raising arm operated by the hydraulic cylinder in a wrong position when the mast is upright. This has been discussed earlier on this thread and corrected by Simon as per the sketch below.
I don`t think we should let Simon take the blame for a wrong drawing. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Mar , 2015, 22:18
Hello Mr. Tore and Maciek,


Great catch on the schnorchel ram arm wrong positing Mr. Tore.  Since Simon is our good buddy we'll give him a "Mulligan" on this one.  In the game of golf a Mulligan is a do-over!  I used part of your drawing and modified it.  I needed space for the combination drawing you previously did for me.


I modified the S-Gerät section per Maciek's suggestions with the info he provided.   I uploaded the latest version of Skizzenbuch to drop box, and please let me know if I got something wrong...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2015, 01:36
Happy easter!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Capt Kremin on 01 Apr , 2015, 03:22
Hi all,
That sums up the Royal  Navy K Class
Regards
Jon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Apr , 2015, 00:33
Don.
Your last update on the schnorchel seems OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Apr , 2015, 18:41
Hello Mr. Tore.


I modified the drawing of the schnorchel ram arm because it didn't look right to me...  I believe it may be closer to correct.  Your opinion?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Apr , 2015, 00:07
Don.
It is fine, below is Simons excellent drawing with my scribbles showing 3 positions of the Schnorchelmast raising.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 04 Apr , 2015, 03:18
Hi Tore,


just another type-seven question. The annotation on the drawing (red circle) stated that the capstan should be removed during war patrols (german: "demontiert bei Fronteinsatz"). Do you know if that is correct resp. if that order was followed? Because looking at u boat pictures or television documentaries many boats had not dismantled the capstans.


Thanks in advance and best regards
Falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Apr , 2015, 06:27
Falo.
The capstan was removable, however we usually kept it in place. I believe most of the VIICs removed it during warpatrol. Below is a  photo showing U 278 returning to Narvik Norway 9th. May 1945 from warpatrol having the capstan removed.  I guess many of the photos are shot in harbour and I guess most of the U boats would have the capstan fitted. In the end I should imagine it was up to the CO.to order it fitted or not. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 04 Apr , 2015, 07:38
Hi Tore,


thank you very much for the information.


Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Apr , 2015, 11:02
Hello Mr. Tore,


I believe the electric motor to drive the capstan and the windless wench was located under the floor in the forward torpedo room.  Later the motor was moved to the ceiling to make room for the LUT control panel and lines to the torpedo tubes.   


What part of the capstan was removed and where was it stored?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Apr , 2015, 21:44
Hello Mr. Tore,


U-278 does not have a KDB showing either...  And I checked some of my other U-Boat photos and some do show the KDB and others don't.  Was it possible to lower it because it was exposed to depth charge damage...?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2015, 02:10
Don
Capstan.
I guess that most of the VIICs had a pneumatic motor situated below the deck between the torpedotubes having a mechanical rod drive up to the capstan gearbox. On some drawings this motor is described as an electric motor, I guess that could be a misunderstanding. Presumeably in the effort to reduce the increased weight of the VIICs/41 the rather heavy drive of this arrangement was substituted by the electric drive shown on U 995. However on most of the drawings including crossections drawings of the VIICs/41, the pneumatic motor and rod drive is maintained. I believe this is a mistake and that all the VIIC/41s had the electric drive, see my images below. It could however be that even the later VIICs got the electric drive as well.
 As we kept the capstan in place all the time, I cannot remember how it was dismantled, I should assume it was just the upper head that was removed and a simple dogclutch or even a square connection to the drive and locking nuts. A storage would probably be under the casing deck were we stored the scepters duly secured as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Apr , 2015, 06:07
Hi Tore,

I guess that most of the VIICs had a pneumatic motor situated below the deck between the torpedotubes having a mechanical rod drive up to the capstan gearbox. On some drawings this motor is described as an electric motor, I guess that could be a misunderstanding. Presumeably in the effort to reduce the increased weight of the VIICs/41 the rather heavy drive of this arrangement was substituted by the electric drive shown on U 995.

Tore, are you sure that U995 was fitted with electric motor? I guess, that the weight reduction was not (would not be) so significant. Let's see: original, pneumatic motor: power 19HP (14 kW), weight 330 kg. Comparable electric motor (driving the main bilge pump): power 20/30 kW, weight 300 kg. I estimate, that weight reduction would be about 100/150 kg. Maybe it would be sufficent...
Moreover, the motor driving the capstan should be (was in case of pneumatic one) controlled from the upper deck. It was done by means of the shaft passing through the pressure hull, which was fitted with the handle. The shaft was driving the air control valve. I don't think that Germans would install the control switches at the upper deck.

For now, I do not have access to my photos, but after weekend I will upload photos of the device, which is (in my opinion) the pneumatic motor with some pneumatic armatures.

Tore, what is the source of the part of your drawing (the white background, with green markings)?

The piece of equipment you have marked with the red arrow (and green color) is the gyro-angle receiver for torpedo tubes. The driving motor (pneumatic in my opinion) is the next to the right (also marked with green color).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Apr , 2015, 06:12
Hi Don,

U-278 does not have a KDB showing either...  And I checked some of my other U-Boat photos and some do show the KDB and others don't.  Was it possible to lower it because it was exposed to depth charge damage...?

Not all U-Boats were fitted with the KDB. KDB was more sensitive and accurate than GHG, but it was extremaly susceptible to damage from depth charges and heavy sea conditions. So it was abandoned on the late war U-Boats.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2015, 08:04
Maciek.
My arrow to the torpedo gyroangle receiver is wrong and done in a hurry. I am not at all sure about the electric capstan motor Maciek, as I cannot remember. As I mentioned above most of the drawings available shows the pneumatic motor,  in fact all my German VIIC/41 drawings, even those after the war. When I checked with U-historia my bad spanish fooled me as I read el motor as electric motor ;D . I agree with Maciek if you move the pneumatic motor up to the top eliminating the rod drive there will be  no saving of weight with an el-motor ;) .The conclusion, the pneumatic drive is still a fact on the late VIICs as well and all of a sudden I can hear the sound of the pneumatic motor running when we were mooring, sorry about the confusion ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Apr , 2015, 11:19
Tore,

one more thing - I suppose, that mechanical characteristic of the DC electric motor is quite inappropriate for mooring work and pulling the anchor. I mean, that during these works, the motor can be installed for a long while, which could easily cause its damage.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Apr , 2015, 14:10
Hello Mr. Tore and Maciek,


I apologize for creating a mess....  In my Skizzenbuch the capstan and anchor windless is listed as a pneumatic-motor.  My question was valid about what part of the capstan was removed, but not the electric motor error on my part.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Apr , 2015, 22:34
Hello Mr. Tore and Maciek,


I corrected the following in Skizzenbuch:
Page 335 - in the drawing top line I corrected a type-o (Fuel was Fueo).
Page 425 - added some info on KDB.
Page 435 - Added info on the capstan.


I uploaded the latest version of Skizzenbuch to dropbox.  I sure hope there are not a whole lot more of my errors.  However, I'm not the best of typist (I use the old hunt and peck system!)...  I know there are people who can type without ever looking at the keyboard, but I'm not one of then.   


When I was working at NCR many years ago, one of my younger co-workers swapped some to the key tops on my computers keyboard.  The next morning, I could not get logged into my system (our screen stayed blank until validated).  Chuck came over and typed my name without looking at the keyboard and my system opened up to the support screen.  Right away I smelled a RAT, and figured out what he did to me...  Come to think about it - that was funny, but not that morning to me!  That afternoon, Chuck needed help with the IBM BIOS vector tables.  I helped him because I don't hold grudges; besides it was to help an NCR field engineer on a customer site and that was our job...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2015, 23:37
Don.
Your update seems OK to me. Don`t bader about creating confusion I am still laughing about my spanish for El motor. As to the finger dancing on the key board, when you are at my age, the nature make sure to use a two fingers dance.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Apr , 2015, 00:35
U 278.
The photo of U- 278 returning from patrol to Narvik, Norway on May 9th 1945 remind me of an incident which happened on the surrender of the Uboats in this area. 12 uboats had already returned to the area following 3 more, including U 278, on May 9th. The Western Allied High Command did not like so many advanced highly operational uboats concentrated that high up north, close to the Soviet occupied county of Finmark Norway, they agreed with the Germans to move all the Uboats still with the German COs and crew, flying a black flag,further south to Trondheim. The formidable fleet of 15 uboats, U-294,- 295, -312, 313,- 363,-427, -481, -668,-716,- 968,- 997, -1165, -278, -and -992 sailed on May 16th 1945  southwards bound. The Western Allied High command forgot however to advice the Norwegian Naval High command and one of our destroyers KNM Stord (which participated in the sinking of the German battleship Scharnhorst) was on another mission on her way north meeting accidentally this formidable submarine fleet. This created a dangerous tense situation before the matter was solved by a signal from KNM Stord to the high command. The 15 Uboats were redirected to Loch Eriboll, Scotland as a beginning of the later Operation Pledge e.g. transfer of 97 uboats from Norway to Scotland, ultimately ending later in operation Deadlight.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Apr , 2015, 01:45
Hi Gentlemen,

Page 425 - added some info on KDB.

Some time ago, I have done a query (related with the KDB) on the reports published on the uboatarchive.net site. The results are here: http://www.forum-marinearchiv.de/smf/index.php/topic,18432.msg204976.html#msg204976 (http://www.forum-marinearchiv.de/smf/index.php/topic,18432.msg204976.html#msg204976)

Generally, it seems that KDB was abandoned since mid-1943.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2015, 21:47
Hello Mr. Tore and Maciek,


I added 2 pages (434-435) to Skizzenbuch to cover RADAR briefly...  I uploaded the latest version of Skizzenbuch to dropbox for your approval.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Apr , 2015, 00:23
Hello Mr. Tore,


I only count 14....


The formidable fleet of 15 U-Boats, U-294, -295, -312, -313, -363, -427, -481, -668, -716, -968, -997, -1165, -278, and -992 sailed on May 16th 1945 southwards bound.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Apr , 2015, 00:55
Don.
Right you are, I forgot the "trigger" for my memory U- 278. As she joined the convoy as well makes the total 15. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Apr , 2015, 10:07
Hello Mr. Tore,


But U-278 is in the list....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Apr , 2015, 11:01
Don.
Indeed, so I had to check the list once more and found that U-318 is missing. In addition to this list the convoys included Grille, Hitlers former yacht, Huscarean a submarine depot ship,  Kamerun a minelayer, Stella Polaris an ex. Norwegian passengervessel and a naval tanker Kaernten. Only the Uboats continued to Loch Eriboll, the other ships continued to Trondheim. U315 CO. Zoller and U 318 CO. Will wanted to go on fighting instead of obeying order from Captain U/B northern waters, Reinhard Suhren. However upon a repeated order from Suhren they gave up.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Apr , 2015, 23:44
Hello Mr. Tore and Maciek,


Mr. Tore - thanks for the additional information.  I have 2 paragraph on page 437 concerning 'After Germany's Surrender" I added stuff like full names and rank.  I hope I didn't get it messed up...


Maciek - thanks for the email and links to the RADAR information.  I read through everything and I believe I got it better,  I made some assumptions on my own as to the location of the receiver modules.  The RADAR pages are 434 - 435.  I hope I'm not way off base...


However, if I am wrong.  Will you all please let me know...  I uploaded the latest version of Skizzenbuch to dropbox.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Apr , 2015, 01:48
Don.
Just a small correction to your last "Skizzenbuch". In addition to U 315 the U-318 CO. Josef Will was in for continue fighting in the beginning.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Apr , 2015, 03:40
Hi Tore,

during some researches I have found information, that U663, before leaving Bergen for her first war patrol, had a collision with something called Felsen. I guess, that it was either ship or underwater rock or shoal. Do you know something having this name near Bergen?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Apr , 2015, 05:12
Maciek.
To my knowledge there are no area or place in Norway called Felsen, neither is it a Norwegian name. However in the Bergen area there are many places which the Germans would name Felsen, so I guess it could be any place on the Norwegian coast.
Today 9. April  we are commemorating 75 years since the German invasion of Norway. Prior to the invasion the famous Polish submarine Orzel operating  in the RN 2nd. submarine flotilla outside the Norwegian coast, sank  April 8. the German troop ship Rio de Janeiro disguised as a cargoship hiding the invasion equipment and troops in the cargohold. As the soldiers were rescued by the Norwegians they told their story but nobody would believed  what they told. That very night to April 9. the invasion came.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Apr , 2015, 12:21
Hello Mr.Tore,


U-318 was not in the list of 15 U-Boats...  Do I need to add another U-Boat to the lost or correct a name?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Apr , 2015, 14:31
Don.
 U 318 was the missing 15 th. Uboat to be added to the list. See my post April 8th. the list is corrected by U 318. The fact is that on May 8th. it was 12 U boats in Narvik, 3 of the last Uboats came in May 9 th. namely U 278, U 318 and U-992. making a total of 15.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 11 Apr , 2015, 00:24
Hello Tore,


me again with another technical question   ;)


Please take a look at the attached pictures, showing the vents near by the kiel of the typeseven. Years ago I read somewhere that the vents were always open (as shown on the kit pictures) no matter if the boat was submerged or operating on the surface. I wonder if this information is correct? Many modelers of the typeseven kits are showing the vents closed, are they wrong?


Thanks in advance
falo


P.S.:
I caught the attached pictures a view years ago from this thread, started by member "Jan" in 2008:
http://models.rokket.biz/index.php?topic=68.0 (http://models.rokket.biz/index.php?topic=68.0)
Today sad to say the pictures of this thread are inactive.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2015, 01:19
Falo.
The Kingstons,(Flutklappen) were shut when you  was alongside for some time f. inst refitting/ repairs. We kept the Kingstons shut when f.inst we expected unauthorised people on board, like a coctail party. It could happen somebody felt like removing the locking pin and pulled one of the ventlever of the main ballast tanks. On my model I made separate Kingston in an open position, see image below.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 11 Apr , 2015, 02:09
Hi Tore,

thank you very much for you fast reply and the attached picture (by the way great looking model).

So if I understand your answer right you operated with opened "Flutklappen"/Kingstons during operations (I mean far away from harbour or yard) no matter if dived or surfaced? Resp. the opened Kingstons were standard during patrols?

Sorry for asking again.

Regards
falo

P.S.: Hence the Eduard photo etchings (1/72 scale) for there Kingstons are not correct because they offer a grid solution (?)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2015, 06:41
Falo.
 Open Kingstons was normal standard during patrol. Normally open all the time when submerged, may be pending circumstances in wartime, shutting the MBT 3 Kingstons during depthcharging. The gratings for the MBT 3 Kingstons on the Edward photo etchings is possibly based on a misunderstanding, assuming as the       " flutklappen" for the Qs have gratings, seen aft of the Kingstons for the saddleballast tanks 4 port and stb., the same would occur for MBT 3 Kingstons.
When I was on board and still a skinny guy I managed to crawl into MBT3 through the Kingstons and did not hit any gratings. :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 11 Apr , 2015, 08:40
Hi Tore,


thanks again, your professional knowledge is striking.


Regards
Falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 11 Apr , 2015, 09:31
Tore, how many Kingstons (outwards opening) per side on a VIIB?
Thanks in advance
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2015, 09:53
SG
I believe the VIIB had 4 Kingstons on each side.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 11 Apr , 2015, 12:09
Thanks a lot, Tore!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Apr , 2015, 12:50
Hello Mr. Tore,


The original list with 14 U-Boats was:


"The formidable fleet of 15 U-Boats, U-294, -295, -312, -313, -363, -427, -481, -668, -716, -968, -997, -1165, -278, and -992 sailed on May 16th 1945 southwards bound."


Then your answer was:


"Indeed, so I had to check the list once more and found that U-318 is missing. In addition to this list the convoys included Grille, Hitlers former yacht, Huscarean a submarine depot ship,  Kamerun a minelayer, Stella Polaris an ex. Norwegian passengervessel and a naval tanker Kaernten. Only the Uboats continued to Loch Eriboll, the other ships continued to Trondheim. U315 CO. Zoller and U 318 CO. Will wanted to go on fighting instead of obeying order from Captain U/B northern waters, Reinhard Suhren. However upon a repeated order from Suhren they gave up. "


In the original list of 14 U-Boats, neither U-315 Zoller's U-Boat or U-318 Will's U-Boat is included.  That's my point of confusion.  If I add U-315, and U-318 to the list, then my list has 16 U-Boats.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2015, 14:46
Don.
U 315 was not amongst the Uboats in Narvik she was already in Trondheim unfit for sea,but the CO. Zoller wanted to continue fighting, my mistake, so we leave him out. The fact is: on May 8th. 1945 following Uboats were in port at Narvik : U-294, U 295, U-312, U-313, U-363, U- 427,  U- 481, U-668, U-716, U 968, U-997 and U-1165, being 12. In the morning May 9th. following Uboats arrived: U 278, U-318 and U-992 making a total of 15. Of these 15,  CO Will on U 318 wanted to continue fighting, but was ordered by Captain Suhrer to surrender and thus the convoy of the 15 uboats mentioned above plus the previously mentioned vessels sailed from Narvik May 16th. bound for Trondheim, but the U-boats were later redirected to Loch Eriboll, Scotland, the other vessels continued to Trondheim. U 315 and Zoller remained in Trondheim. I hope we got it right by now. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Apr , 2015, 00:27
Hello Mr. Tore and Maciek,


I updated Skizzenbuch with RADAR and GSR info and I corrected the info about the relocation of 15 U-Boats at the end of WWII.  While searching the internet, I found that I did NOT have a correct photo of Buchheim, or the correct information...WOW what a screw up that would have been!  I believe I have the correct info and photo.  The younger Buchheim does resemble the older Buchheim...


I uploaded the latest version of Skizzenbuch to dropbox, all 457 pages...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2015, 05:51
Don.
As far as the 15 uboats concerns your corrections seems OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Apr , 2015, 16:06
Hello Mr. Tore and Maciek,


I received an email this morning from Schiffer Publishing stating that they will be sending me a contract for:


"Skizzenbuch: Type VII C U-Boat Design and Functionality"


This afternoon my stomach still has "Butterflies" form the news.  I guess I was always expecting a rejection and this has not set in as of yet.  However, I have you and Maciek to thank for all your help with the book, and I will ask another favor.  Please take a close look at Skizzenbuch and if anything looks wrong or questionable, then please advise me of such.


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Apr , 2015, 22:53
Hello Mr. Tore and Maciek,


I just finished updating the GSR pages in Skizzenbuch and uploaded something like the Final version pending corrections to dropbox for your approval...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2015, 23:49
Don.
Congratulation!
 As the book contains today 457 pages it would take some time to check the whole book and may be the publisher would have a saying as well. I shall revert as time permits with possible remarks as I start checking the details whithin my knowledge.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2015, 01:21
Hydroplanes.
The most common visible mistakes made by modelbuilders can be noticed on the hydroplanes, as the building kits as well as many GA drawings contains the same mistakes. On most of the GA drawings the hydroplane shafts are indicated as a shaft centerline going through the hydroplane guard as an outer support for the plane. The plane is made of welded steelplating filled with impregnated wood and the plane shaft ends about half way into the planes where a fixing nut is situated. The access is via a small bolted cover. On the aft hydroplanes it is a shut connection between the guard and the plane by a small stubshaft which has a small nut outside the guard, this is not a support, but a guard to prevent ropes or wires to come in between the plane and guard. Once we had an incident up north of Scotland during a night anchoring near Scapa Flow. When rising the anchor in the morning we discovered that the anchorchain had stuck between the guard and the forward hydroplane. No 1 had to dive in the cold water using his longjohns as wetsuit to release the chain. On that occasion it would have been handy to have a shut opening between the guard and the forward hydroplanes as well.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2015, 06:32
Don.
Skizzenbuch. I have read the page 1-31 of the buch and recommend to change on page 31 last sentence on the main drainpump starting with " when draining from the forward  and aft.... by the following:  "The pump has a capacity of 1300 l/ min against up to 15 meters head in parallel, single stage mode and up to 500 l/min against a head of up to 100m in series, two stage mode." You can of course maintain the pretty obvious comments on the suction resistance, which in addition to the pipelength is depending upon the valves and filters in the system.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 14 Apr , 2015, 10:28
Tore, thats a great clarification! I had always thought that there was a connection between the forward hydroplanes and their guards.
Outstanding, Tore, as usual!

PS. warm blankets and a hot cup of joe for n.1 after his exploit in the freezing water? 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Apr , 2015, 10:46
Tore, that's a great clarification! I had always thought that there was a connection between the forward hydroplanes and their guards.
Outstanding, Tore, as usual!

PS. warm blankets and a hot cup of Joe for n.1 after his exploit in the freezing water? 
SG
When at anchor, not leaving before the next morning the Officers were allowed one Anchor dram, a whisky shot, pro man and that`s what he got ( the  night before). I am afraid we did`t have any extra blankets so he had to use his bunkblankets. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 14 Apr , 2015, 11:02
 ;D ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Apr , 2015, 12:11
Hello Mr. Tore,


I will make the changes to page 31 (already done so just waiting before redoing the complete PDF file)...


Thanks.


With regards to the model's forward hydroplane; my OTW Type VIIC U-Boat Kit (about $1,100 fiberglass and brass 1/32 scale) has a solid brass leading faring with two heavy brass studs that extend through the fiberglass hull.  I threaded the brass studs and bolted the fairings to the fiberglass hull.  The fairings don't have the incorrect end nuts.  However, there a small stud that extends into the outside of the forward hydroplane, but that is not visible.  So I guess OTW got it right...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Apr , 2015, 01:18
Don.
Skizzenbuch page 39-46.
I have read through these pages and can`t find anything wrong but still I am afraid that the readers might have difficulties to understand the system. On page 39 you introduce the Q system by quoting the translation of the German Divingregulation. I am afraid the document has a fraction of "google translation" as might happen when the translator do not fully understand what the text describes. Furthermore these instructions are general and concerns a number of different types of U-boats.
A simpler text for the readers could be, after giving a short description of the Q (Untertriebzelle) system:


   Crash dive procedure.
 Preparing for crashdive implies filling the Q by opening the Q- floodvalves at the bottom of the tanks and the inside Q-ventvalve venting the tank through the mufflers in the control room. The boat is now floating heavy on the ballasttanks. When crash dive orders are given the boat is heavier than normal and dive quicker through the surface. Experience shows penetrating the surface is the crucial time delaying factor. As soon as the boat is submerged the normal trim , speed and hydroplanes controls the descend effectively and the Q has a smaller effect. Thus the Q is blown immediately  after boat is submerged 8-10 meter, saving HP air. Blowing is done by shutting the inboard Q-ventvalve,  now the common Q-ventpipe can be used as Q- blowing pipe and air via the common Q- HP blowingvalve is admitted to the pipe and in to the Q-tanks forcing water out of the bottom Q-floodvalves. The Q tanks are pressureproof for external pressure by internal strengthening, but have limitation as to internal pressure not exceeding 2 kg/cm2 above the ambient external pressure hence the Q system has differential gauges which are to be monitored to keep the inside tankpressure max.2 kg/cm2 above the prevailing external seapressure.
The waterlevel inside the Q tanks are monitored by testcocks. When air is coming out of the lower testpipe the Q floodvalves are shut and blowing is stopped. When the boat ascend the pressure differential gauges are monitored and possible overpressure is released into the boat.

The essentials of the above is repeated in different wording on page 39 through 44. which might be confusing. The artificial use of "express" would be confusing as well, as in RN English we use blow Q and vent Q.
Have a look at it with the eyes of a non expert reader and see if it is worth while changing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Apr , 2015, 03:55
Hi Tore,

The artificial use of "express" would be confusing as well, as in RN English we use blow Q and vent Q.

Well, I suppose, that term "express" was used to indicate that Germans used different terms related with blowing:
- anblasen - blowing tanks with compressed air
- ausblasen - blowing tanks with exhaust gases
- ausdrucken - blowing negative tanks
It can easily make confusion, as in RN English (or US Navy English) there are no equivalents of these terms.

I agree with you, that in such case, the quotation from the "Diving regulations" should be replaced with reworded description.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Apr , 2015, 22:13
Hello Mr. Tore and Maciek,


I really learned a lot form the discussion about page 39...  I updated page 31 as per Mr. Tore's previous recommendation.  I swapped page 38 and page 39 for cosmetic reasons, and updated page 38 to reflect the discussion which I found to be fascinating!  Please advise if you all approve of the new page 38.


I placed the latest version of Skizzenbuch into dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2015, 08:15
Don.
Your update seems to be OK. A small remark. On page 42 you have a cross section drawing of the Q tank, referring to the drawing at right, the drawing is to the left.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2015, 11:20
Don.
Regulating tanks.
The description used by quoting the translation of the German divingmanual resembles what we previously have discussed under Q tanks nothing particularly wrong but difficult to understand for the readers speaking English.
I have made another attempt to describe the regulating tank system as follows:
The regulating tanks are provided for compensating the submarines daily change of weight and buoyancy due to consumption, leakages, seawaterconditions (salinity and temperature) and displacement changes with regards to compression of the pressurehull during deep diving.
There are four regulating saddletanks, two ( reg. tanks 2 port and starboard) each having a capacity of 7.600 m3 and two (reg. and f.oil. tks no 1 port and stb.) each having a capacity of 4.700m3. The latter tanks can be used as reserve fueloil tanks.
All the tanks are made pressureproof having a testpressure of 14 kg/cm2. If the differential pressure between two adjacent tanks exceeds 14 kg/cm2 f. inst in the  reg. tank 2 between Q and reg./ fuel oiltank 1 the two latter tanks should be put under some pressure to avoid exceeding the max. differential pressure and rupture of the bulkhead between the tanks.
All the tanks have graded waterlevel gauges in the controlroom showing the prevailing watercontents. All tanks can be operated by the main drainage pump, aux trim and drainage pump as well as airpressure.
When diving a pair of regulatingtanks are made ready for flooding and shallow water  discharging by air. The other tanks connected to the main drainage pump in two stage configuration ready for for discharging at greater depths and the tanks are put under airpressure app. 10-12 kg/cm2.
When cruising at periscope depth a decreasing of weight is done by admitting pressure air to the tank in shallow water configuration pushing the water out of the tank thus avoiding to use the main drainage pump set to deep discharging of the deepdiving regulating tanks.
An increasing in weight is done by filling the tanks via the fine filling seavalve and flowmeter.

When going deeper the pressurehull is compressed and the displacement is becoming smaller hence the buoyancy is less. This has to be compensated by discharging water from the regulating tank in deep dive mode. The required capacity would be appr. 100l/10m, but usually more is discharged to compensate for leakages.
Plate 7 shows the regulating tank system, however the real system deviates somewhat from plate 7.
Below I have tried to sketch an image to show how I assume the system works.
The fuel/regulating tank 1 port and stb. (red) are selected as the flooding/ discharging shallow water tanks. Flooding is done via the fine flood seavalve and meter, the discharge is done by admitting air pressure to the tanks (red pipelines), forcing the water either through the normal sea valve or the seavalve to MBT 3.
The regulating tanks no 2 port and stb. (yellow) are in deep water configuration having the main drainagepump impellers in series and the tank airpressure up to 14 kg/cm2. Discharge pipe (yellow) directly via the normal overboard valve or via MBT 3.
The above suggestion is one of several possible configuration indicating the working of the system. I have left out the fuelconfiguration of the regulating/ fueloil tanks for simplification.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2015, 17:35

Hello Mr. Tore,

"the discharge is done by admitting air pressure to the tanks (red pipelines), forcing the water either through the normal sea valve or the sea valve to MBT 3."

I  believe this should be the "(GREEN Piplines)" ???


I have done as you suggested and added 2 pages to Skizzenbuch to include your excellent drawing and description.  I re-indexed the book and re-numbered the 3 MS Word sections and re-compiled them into one PDF.  I have loaded the latest version of Skizzenbuch into dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2015, 23:43
Don.
Somehow the word pipelines was added after the red. It was meant to be red, referring to the tank, if referring to the air/vent it should of course be green.  If you look closer to the system you`ll see it resembles the Q system, using the same pipeline for "blowing" (admitting air) and venting, may be you could add that in the text. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Apr , 2015, 01:35
Don.
On page 38 you have a definition of the 3 different blowing orders used by the Germans. Your definition of 3. "Ausdrucken" is blowing the negative tanks. I don`t think this is quite correct as it is more general and concerns other tanks as well. If you look at plate 7 you shall see an airpipe into the common vent/blowpipe for the regulating tanks 1 and 2 marked "Ausdruck leitung". In this connection I believe it is meant an air pipe to put the tanks under pressure. This might be for transfer of water, as well a compensating for pressure differentials. An order in RN English for that would be: Pressurize tank no... to ... kg/CM2. My revised plate 7 sketch has a minor mistake as the " Ausdruck" airpipe for port regulating tanks did not have the blue colour as corrected on the revised sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Apr , 2015, 08:15
Don.
Minor correction page 44 left photo reliefvalve. Page 46 pressure differential manometer, gauge written gage, may be you can skip the gauge. Same thing in the last sentence down the page.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Apr , 2015, 22:34
Hello Mr. Tore,

Great find of the wrong spelling of "Relief."  That would have been caught with spell checker because it was embedded in a photo.  I had gauge wrong in many places and fixed it with a search and replace...

I used your latest drawing and worked on the definition issue...  a strange thing; my internet translator does the following:

ausdruck = expression
ausdrucker = print out

That certainly is confusing!

I uploaded the latest version of Skizzenbuch to dropbox...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2015, 01:39
Don.
Your latest correction seems to be OK to me as long as you take the blame for my text you are using the word I. ;D
Language can sometimes be difficult particularly when selecting words in a complicated technical description as you have to know the subject fairy well to choose the right words. The difference between submarine anblasen, ausdrucken and ausblasen is a bit complicated no wonder you are confused when you dictionary tell you ausdrucker means print out.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2015, 15:43
Hello Mr. Tore,


That was a type-O it was ausdruchen (print out)... The translation site uses 4 different translators in its presentation (Microsoft, Google, Babalon, and Prompt-Online).


http://imtranslator.net/compare/german/to-english/translation/


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2015, 21:44
Hello Mr. Tore,

In order to eliminate any possibility of confusing the reader of Skizzenbuch, I took your suggestion and updated pages 38 through 46.  I uploaded the latest version of Skizzenbuch to dropbox.

Please advise if I got anything backwards, or used the wrong context...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Apr , 2015, 03:07
Don.
You update seems OK. to me, just a small misprint i qouting my remarks on page 38..... " as soon as the U-boat is submerged at normal trim, speed and the hydroplanes control the decent effectively.... I wrote descent but I hope the control goes decent as well ;D .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Apr , 2015, 16:30
Hello Mr. Tore,

Just for my own info....

I have a question about the regulating tanks set-up as a shallow dive tank.  When you want to decrease the contents of the tank, in this case you use air pressure to discharge some water into the sea, or MBT 3. Do you bypass the Main bilge pump with the two valve chests, or do you use the pump?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Apr , 2015, 18:14
Hello Mr. Tore,

I corrected the spelling of "descent" on page 38, and added some context to page 47.  I uploaded the latest version of Skizzenbuch to Dropbox...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Apr , 2015, 23:50
Don.
You  normally don`t discharge the water by air through the main bilgepump pump.  In this case I guess I would discharge to the main valvechest and to the sea valve ,
However if the relevant tank is the reg and fueloil tank no 1 recently used as fueltank I would discharge into MBT 3. Just to give an indication of the many aspects and alternatives you have, I guess there is no single right answer for all conditions. You can compare a VIIC with an instrument well designed and the men that plays her as musicians. There are many ways to get the best out of her, depending upon the skill of the players, a manual cannot cope with all the variables and as such tell you what to do. The standard of the boat is set by the knowledge, skill and experience of the crew.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Apr , 2015, 01:06
Transferring liquids in a confined space is in some cases difficult to understand.
May be the trim system used for compensating for weight shifting fore and aft gives an explanation.
The image of the system is shown below. One trimtank is situated forward and one aft, an approximate distance between the tanks of some 41,6 meters gives a proper correctional momentum by shifting a relatively small amount of water in the system. The water can be transferred either by the trimpump or airpressure. When the system is operated by the trimpump, water is pumped through the trimline. The volume of the shifting air and water in the confined system is constant (you don`t add air or water to the  system) and according to plate 6 you don`t have local venting, everything is centralized in the controlroom. However as the volume of  water is shifted, the air volum ("venting") has to be shifted as well. This can be done by the airpipe between the tanks by putting the blow/ venting cock in the pumping position, straight through the cock as indicated on my image below, allowing the air to move between the tanks. Thus by pumping water from one tank to the other the ventingair can be shifted to the opposite tank via the airpipe. 
   When  trimming by airpressure the valves to and from the trimpump are shut, the water distributing ( Schalter) valve is put in a middle position and you have a direct water connection  between the two tanks, shortcutting the trimpump. When selecting the tank for air pressurizing (blowing) you put the air / venting cock in the airpipe in the required position and as you pressurize one tank by the air blow valve,  you vent the other. As you admit air to the system the tanks have to be vented into the boat, which means increasing the inside pressure of the pressure hull.
We usually used the trimpump avoiding increasing the ambient air pressure in the boat.
 The above is just an example to illustrate the physics of moving liquids and air in a confined space like a submarine.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Apr , 2015, 19:15
Hello Mr. Tore,

I added some info to the compensation section and uploaded the latest version of Skizzenbuch to dropbox.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2015, 00:17
Don.
I think you put the description of the two ways of trimming just on the right place.
 When you see the VIIC system like the trim arrangement photo in the controlroom, having all the rough essentials in one place for trimming, it strikes me we did not badder to have a special place for the trimoperator who should handle the system. In to days submarines I guess the same system is installed, however the operator is probably sitting in a proper designed chair, looking at a screen, pushing coloured buttons for the same functions (and even more) as we turned the valves and cocks standing, stretching and twisting around using our ears, noses and eyes to monitor the operation. It calls for some reflections, today you put in  extra technical elements between the human operator and the piece of equipment we are controlling, are we loosing our the ability to use our senses by introducing  extra elements which might have a potential of failures? The VIICs are one of the last advanced mechanical, directly controlled submarines which made it unique though cumbersome to operate and maintain, thus having the disadvantage of requiring a large crew. To days submarines of the same size would probably have a crew of less than half of the VIICs and still a larger striking power.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2015, 09:54
Don.
Referring to page 78 having showing an image of the fueloil watercompensating system plate 10 you have a description of same underneath starting with "when the U- Boat submerges.... I believe your explanation is a bit unclear and would suggest a text some thing like this : When the U-boat submerges the header tank systempressure is kept constant, equal to a liquid column height from the compensating pipes sea inlet in the external fueltanks and the top of the header tank waterlevel, regardless the divingdepth of the U-Boat. The internal fuel tanks are shut to the external compensating system by the hull valves "a" on plate 10. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Apr , 2015, 10:40
Hi Tore,

while cruising submerged (using electric motors), did you shut the internal fuel tanks to the external compensating system? I mean, if it was common practise to isolate them from the external pressure?

In the KTB from the 2nd war patrol of U663 there are described some damages:
Quote
Schaden: 25 cm langer Riβ in TZ 3 durch Sull Mannloch, Riβstelle nach innen gedruckt. TB 1 und 2 innen ständig unter Druck. Wassereinbruch 8 t in 3 Std. im Dieselraum aus Entwässerungsschalter.

My translation:
Quote
Damages: The coaming of the manhole of the main ballast tank 3 torn. The edges are bent inside. Internal fuel oil tanks 1 and 2 remain under (external?) pressure. Water intake 8 tons per 3 hours in diesel engine room through the bilge/drain system.

From the description I suppose, that internal fuel oil tanks are somehow no more pressure resistant. And thus my initial question...

And by the way - what do you think about this torn of the coaming? As far as I know, the only manholes of the main ballast tank 3 are located in the control room, so I wonder, how they could damaged (and if the coaming is needed at all inside the boat)?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2015, 14:00
Maciek.
As a rule we shut all the boardvalves not needed when diving and for sure the compensating water to the inboard fueltanks.
With regard to the manhole and damage on MBT 3 I wander what caused the damage, was it by blowing the tank? or was it depthcharging or deepdiving. As adviced previously U 926 got a damage on MBT 3 by blowing.
MBT 3 has separate Kingstons and blowing and venting valves for starboard and port side. On several drawings the tank is drawn and  marked as MBT 3 port and stb. Between the port and starboard side of the tank there is a center bulkhead, I believe not pressureproof, you can see this on several drawings and on U-historia images the bulkhead is used for supporting the bearings for the  operating rods for the Kingstons on both sides. In this bulkhead you have a manhole see my image below, I should not expect a coaming on this cover. I guess you can easily damage this bulkhead if the differential pressure between the two sides become to large, but I am at a loss to explain how they could observe the damage . This is just a far fetched idea and bad assumption from my side." TB 1 und 2 staendig unter druck" does not give much meaning to me. The tanks have reliefvalves both for pressure and under pressure, moreover you could shut the hullvalve and relieve the pressure in to the wastetank or other inside tanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Apr , 2015, 18:58
Hello Mr. Tore and Maciek,

It looks like all the damages to MBT 3 were the results of a depth charge attack from a destroyer on the 13th and 14th of December 42 during their 1st war patrol.  Overall, U-663 was just too close to the pounding of depth charges for 2 days.  MBT 1 and MBT 5 have comb type grilling over the vents on the top side.  I could see them getting pushed inward from depth charge explosion pressure...

U-663 History
1st patrol 5.11.42 left Bergen returned Brest - Damaged 31.12.42 (repairs took about 2 months)
                4.3.43 left Brest returned 6.3.43
2nd patrol 10.3.43 left Brest returned Brest 4.4.43 - no damage reports
3rd patrol 5.5.43 left Brest - 7.5.43 attacked by aircraft Sunderland (RAAF) declared lost 8.5.43 - no survivors.

The very short life span of U-663.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Apr , 2015, 21:04
Hello Mr. Tore,

I changed page 78 as suggested and uploaded the latest version of Skizzenbuch to dropbox...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Apr , 2015, 00:01
Maciek.
The report of U 663 says "Wassereinbruch 8 t in 3 Std im dieselraum aus entwaesserungs schalter." I guess in case of depthcharging, without shutting the board valve exposing the internal compensating system for excessive pressure fluctuation like a depthcharging, the two cocks marked on the drawing might burst and you get a substantial  waterflow into the engine room via the broken entwaesserungs schalter. It t. However you could avoid exposing the internal fueltanks for same pressure fluctuations even with open hull valve by shutting the valves "c" to the tank 1 and 2. It looks indeed like they did not shut the hullvalve, neither did they shut the c valves when the increased internal pressure occurred which could be a fatal mistake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Apr , 2015, 09:34
Hi Gentlemen,

Tore, thank you for your answer.

With regard to the manhole and damage on MBT 3 I wander what caused the damage, was it by blowing the tank? or was it depthcharging or deepdiving.

The damages were caused by depth charging. While pursuing SC-123 convoy, she was spotted by HMS Vanessa (D29) and forced to dive. During the first (of four) attack, destroyer dropped eight well-aimed depth-charges.

TB 1 und 2 staendig unter druck" does not give much meaning to me. The tanks have reliefvalves both for pressure and under pressure, moreover you could shut the hullvalve and relieve the pressure in to the wastetank or other inside tanks.

I suspected, that somehow the tanks themselves or the compensating installation was not tight and exposed to the external sea pressure.

The report of U 663 says "Wassereinbruch 8 t in 3 Std im dieselraum aus entwaesserungs schalter." I guess in case of depthcharging, without shutting the board valve exposing the internal compensating system for excessive pressure fluctuation like a depthcharging, the two cocks marked on the drawing might burst and you get a substantial  waterflow into the engine room via the broken entwaesserungs schalter. It t. However you could avoid exposing the internal fueltanks for same pressure fluctuations even with open hull valve by shutting the valves "c" to the tank 1 and 2. It looks indeed like they did not shut the hullvalve, neither did they shut the c valves when the increased internal pressure occurred which could be a fatal mistake.

It makes sense to me.

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Apr , 2015, 23:30
Don
Your latest update seems OK to me. Time has come for me to move up to my summerfarm very remote in the deep forrests which means I shall be without internet from tommorrow and  for some time, may be up to two weeks, before I get a satelite connection. In the meantime I shall have a further study of your Skizzenbuch and revert to same when I`ll be on line again. 

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Apr , 2015, 10:56
Hello Mr. Tore,


Have a good vacation on your summer farm in the forest and I hope its not too far from neighbors or friends.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Apr , 2015, 18:01
Hello Mr. Tore and Maciek,

Today, I just completed my permission list from the three (3) web sites which provided the documents for Skizzenbuch:

uboatarchive.net - Skizzenbuch 34 plates, U-570 reports and B/W photos
u-historia.com - Line drawings and a few color photos
uboataces.com - Most of the high resolution color photos we used for illustrations came from their CD

I will most likely sign and return the book contract to Schiffer Publishing, Ltd., next week...  The publisher suggested I get a small photo of my contributors and a short Biography.  I plan on replacing the photo of me at the end of the book with a better photo when I was at the Chicago Museum of Science and Industry.   I'm not sure if it will happen, but I asked my friend Jak. P. Mallmann Showell who has written many books about the history of U-Boats during WWII to do a short "Forward."  If that happens, I think it would be great!

Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2015, 00:59
Don.
I am finally back on the net. Good to learn you probably shall sign the contract next week. I have checked the skizzenbook up to page 77 and have a comment on page 69 "e" valve selection on the fuel daytank. I think you somehow got it wrong. Below I have made a sketch showing how the selectioncock is working I guess is  selfexplaining. Otherwise I cannot find anything wrong. However it strikes me when you substitute  an original German manual text translated  into English with an alternative text which may be a simpler to understand for a layman, you maintain the translated text from original German documents as well . For a layman the translated manual text is not easy to read as the English text sometimes can give an impression that the translator in spite of using the correct words sometimes do not fully understand the meaning of what is translated. It is not easy to translate technical manuals as you really have to know the working of the items you describe.  I guess what I am trying to say is, you get a double text on the same subject which might be confusing for the layman reader, for a professional however the original translated text shall be OK and that`s perhaps why you kept it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 May , 2015, 08:28
Don.
Skizzenbuch.  I don`t fully understand your text on page 79 under plate 10. The system works like this: If submerged and the hullvale "a" leaks or is left open, the internal pipesystem shall be exposed to the seapressure but is protected by the reliefvalve "f" in the engineroom. The internal fueltanks 1 and 2 are protected by the shut off valves "C". If these valves are open each fuel tank has a unit consisting of a reliefvalve for overpressure "f1"and under pressure "f2", fitted with a manometer for the absolute pressure prevailing in the tanks. These units protect the tanks for both over- and underpressures.
See my answer to Maciek 2651 and 2653.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 May , 2015, 03:11
Don.
Skizzenbuch. On page 88 you have an elaborate description of the assumed waterlevel height of the compensating tank introducing the keel and the wind deflector. This might be complicated to follow for the average reader and as all the figures we have of the tank  would be approximate anyhow, I guess it would be simpler just to  introduce the approximate figures directly. As you see on my image below the watersupply pipe from the engines ends up in a pipe some 20 cm above the bottom of the tank to prevent a complete draining when the engines are stopped. When the engines are running the water is filling the tank until the overboard pipe approximately. 10 cm. from the top of the tank when the water goes overboard normally keeping the tank topped up 10 cm. from the topcover. Further the bottom of internal fueltanks are not going all the way to the lowest part of the pressurehull (see my sketch). This means that surfaced an estimated pressure of the internal fueltanks open to the system might vary  between 740 and 700 cm. watercolumn approximately corresponding to 0.74 and 0.70 kg/cm2.  or 10,5 and 9,95 lbs/sq. inch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 May , 2015, 07:25
Don.
Having checked your Skizzenbook up to page 108, I have the following last remarks: Page 109 Safety valves . You have a remark on the safety valve (Reliefvalve) on the main blowingpanel dealing with the event that you had an air pressure supply of only 25 kg/cm2 or less that you could adjust the reliefvalve or improvise. In such unlikely event you don`t have to do any thing else to the relief valve or other components but blowing whatever you got of air so I suggest you skip that paragraph.
On your description of the electric aircompressor,first line lunching to be substituted with launching torpedoes :D .
The description of the Junker compressor I believe is superfluous as you have a description on page 92 through 97.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2015, 00:17
Don.
Skizzenbuch page 116. Coolingwater. The header tank uses the water to pressurize the RFO tanks... I suggest you revise the text to: ...is used for pressurizing and watercompensating of all fueltanks except RFO 1. The excess water goes overboard via the external mufflers and headertank overflow.
On the same page you mention the coolingwater for the Junker, I suggest you change the text to:....... diesel powered unit having its own attached rotary vane coolingwater pump and external exhaust cooling watersystem via e3.

Page 123. The text starting with:  The engines were Krupp  for the VII Cs..... I think you quoted my text dealing with a description of the main engine of KNM Kaura ex U-995. As you know the VII Cs main engines could be Krupp Germania Werft or MAN the latter having the Buchi system exhaustdriven supercharger I suggest you rewrite the text to make it more general for the VII Cs.
By this your Skizzenbuch is checked up to page 133.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2015, 07:57
Don.
Skizzenbuch page 157. Starting procedure main engine. I suggest you change the sentence .....the starting handle is put in a start position...... with: the startinghandle is put in a start position, air is admitted to the top cylinder of the starting valve pushing the valverod.....
Page 170. Stb. exhaust blowing valve in the engine room. You write this as black, it is green ( not very important as we did not have these colours on the valve wheels.
You describe correctly that the bores in the  main exhaust valves wheels were  for putting a bar into the wheel for a larger torque. We did not use the bar very often but waited until we reached some 2-4 meters depth creating a nice backpressure when we were grinding the outer exhaustvalve, however when we reached 5-6 meters the backpressure would be too large for the pneumatic motors to turn the valve disc so you had to be quick.
A minor thing, you are quoting some of my remarks where I am referring what I or we experienced or did under different circumstances like page on page 157 .... I personally checked the combustion by........It might give a confusing or even wrong impression without mentioning who are behind I or we. You could rewrite into a more general form skipping the we and I or quoting who is behind the statement, otherwise you get the blame for my possible mistakes ;D .
Your Skizzenbuch has now been checked up to page 172.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 May , 2015, 14:33
Hello Mr. Tore,


Post 1752, I used your latest drawing as suggested.  Is the text OK?  I'm not sure you wanted me to change anything.  I have bee AWOL (Absent With Our Leave) for this weekend and will get back to work on Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 May , 2015, 00:12
Hello Mr. Tore,


I believe I got everything updated...  I'm not too sure what you wanted me to change on page 109...  I left the paragraph in there about the Junkers compressor because of too much open space if deleted...


I uploaded the latest version of Skizzenbuch into dropbox...


Thank you for taking your time to correct my typing errors.  I don't usually have torpedoes for 'Lunch"!!!
(http://models.rokket.biz/Smileys/default/embarrassed.gif)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 May , 2015, 01:08
Don.
Your reply #2664 I am not sure which drawing and text you are referring to as  post nos are just the a number indicating my total posts, could you refer to reply number?
I have checked your Skizzenbuch 1 before your update of today up to page 193 and have a few remarks. Page 187 clutch for hydroplanes you are quoting my description referring to the coloured sketch 2. paragraph. Somehow the green coloured part is quoted as wormwheel housing. The housing is not shown and the green parts are the e-motor worm gearwheel assembly.
On page 188 you have a funny misspelling ....... hydroplane setting while cursing ;D  on the surface.....
On page 191 you are referring to the inclinometer (along ship) as showing the tilt, we normally used trim. There is another inclinometer showing the list ( atwartship tilt) I remember looking frequently on the device in rough weather in view of the battery acidspill. I guess it was in the control room but can`t find it on U-995, may be somebody pinched it.
Page 193....... Keel depth varies slightly depending on the loadfactor.... It depends on the sea salinity and temperature as well, you see it on the classification marks on every shipside.
As to your to days #2665 I shall revert later.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 May , 2015, 21:03
Hello Mr. Tore,


I made the suggested changes and spelling corrections...  I uploaded the latest version of Skizzenbuck to dropbox.


 "Hydroplane settings while cursing on the surface" was changed to "Hydroplane settings while cruising on the surface"  I guess I misspelled 'Cruising" and word automatically inserted "cursing"…… Then after that, it passed Spell Check! ;D   Many times ???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 May , 2015, 01:46
Don.
Skizzenbuch1 of today:  page 78 text under image misprint .... height of the water column form the deck...... You are on most of the text concerning fueloil tanks as from page 78 and onwards referring to RFO tanks, you better check these texts as most of them concerns FO tanks and not only RFO (reserve fuel oil tanks).
Page 79 see my reply #2659
Page 116...... The RFO tanks and the excess water is drained back.... suggest you skip this sentence.
As far as I can see apart from the above correction everything is OK up to page 193.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 May , 2015, 06:46
Don.
Skizzenbuch page 199. You describe the man operating the engine telegraph as giving order to the electrician and that he responds after the command is completed. This not quite the case, the engine telegraph is used both for giving orders to the dieselroom as well as the E-room depending on the prevailing propulsion configuration. In this case it could f.i. be a dieselconfiguration on a surface attack and the orders would have been given to the diesel engineers. In any case the order procedure is different from what is stated by you. The speed order is given by the officer on watch, only to be overruled by the CO, in that case he takes over the command. When the order is given to the helmsman wherever he is placed, he put the engine telegraph pointer to the ordered speed, repeating the order to the officer on watch (or CO) the order is transmitted to the diesel room or E-room depending on the configuration. The engineer or electrician put the telegraph pointer to the ordered speed prior to the execution, not after the order is executed, as a sign they have understood the order correctly and the helmsman report to the officer on watch.
The "speedgauges as you calls it" are called tachometers. Skizzenbook checked up to page 199.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 May , 2015, 20:12
Hello Mr. Tore,


I believe I have everything up to date...  I re-wrote 3 paragraphs  - pages 78, 116, and 199.  I believe they reflect your suggestions.  Please let me know if they are OK.  I uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2015, 00:37
Don.
Page 78. Normally when you use the compensating water you only pressurize the fuel tanks and do not have a water consumption. Only the bunker fueltanks selected to supply fuel to the diesel engine daytanks would require compensating water equal to that of one of the daytanks, a total capacity 730 litres. The engines have at normal cruising speed an average total consumption of say 420 litres/hour, so lets assume you top up the tank once pr. hour by 420 litres you have the average compensatingwater consumption. Compared to the total cooling water supply from the diesels say 40.000 litres/hour only 10% of the cooling water is used for watercompensating while cruising by diesels. So you statement..... most of the water is channeled to the fueltanks....should be corrected.
Page 199.   ... the engine room dieselengineer or the E-room electrician will respond with his telegraph unit after the command has been completed and then the.......
The engineer or the electrician acknowledge the order prior to the execution of the telegraph order.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2015, 11:31
Hello Mr. Tore,


I have a question about the muffler spark suppressor... Does it spray water onto the exhaust to extinguish the sparks?  I thought I read something about white smoke coming from the U-Boat exhaust (possibly steam)?  If that were the case, then they would only want to use the spark suppressor at night to eliminate that tell-tale glow of the U-Boat's exhaust so not to give away its location...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2015, 12:45
Hello Mr. Tore.

Are these statements correct?

"The day tank has two sides and each has a capacity of 720 Liters"

"Compared to the cooling water supplied from the diesels approximately 4,000 liters/hour, only about 10% of the cooling water is used for water compensating while cruising by diesel."


If we top up the tank once an hour...  Then that means we switch tanks and top up the tank that was being used and we have an hour for the fuel to settle before switching again.  These sound more like hour tanks rather than day tanks...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2015, 13:26
Don.
 I don`t think you should take the daytank on a submarine literally. The expression is used by the enginecrew and comes from the merchant marine where they have the space for a 24 hours tank. You may use the expression setling tank or even headertank. I guess the total capacity for both tanks together is 720 liters in excess of 6 US barrels. If you look at the both tanks together I don`t think they have the capacity of a total of 12-13 barrels.  The tankcontent is not very much and indeed it is a short setling time, but it is better that taking the fuel directly from the bunkertanks. All these figures are only approximate figures roughly calculated by me to illustrate the working of the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2015, 13:59
Don.
Spark arrestor. I think the VIICs have a number of different exhaust outlets and possibly spark arrestors. I have put up some 5-6 versions on the images below. So I have to answer you questions more generally. The sparkarrestors for submarines may be of two executions wet or dry. In the wet execution the engine coolingwater is sprayed into the arrestor or the gases are emitted into a coolingwater well  in case same is placed above the watersurface (sea) or the exhaust is emitted below the watersurface (sea) without a special casing for a spark arrestor. The latter execution was the original U-995 design, this has been changed on today museum U-995 as shown on the image. The dry sparkarrestor has an intricate system of baffel plates to arrest the sparks inside a casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 May , 2015, 00:35
Hello Mr. Tore,

I added the info you provided on the exhaust location and the spark suppressor on page 117.  I also added your info to page 78 and I did a lot of research and add some additional info as well.  However, as always -  if I got it wrong, then please tell me so and I will correct it.

I uploaded the latest version of Skizzenbuch to dropbox...

Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2015, 07:57
Don.
Page 78. Running one diesel at full ahead on one shaft using the generator to power the other shaft by E motor at half the propeller rpm as of the "diesel shaft" was a very seldom configuration. You would get an unequal load on the propellers requiring a constant  correction by the rudders, resulting in a increased hull resistance. Depending on circumstances as when you had to be at your destination and your battery charge, you choose the configuration. I guess normally I would have run both diesels at 3/4 load if no charging was required. If charging was required, as was very often the case, I would put on the battery charging on both diesels, and adjusting the load and rpm at the lowest specific fuelconsumption of the diesels. But we did not often made to much theoretical speculation around the matter, it is so many variables like hullresistance which varies with the  maintenance, optimal variable specific fuelconsumption of the diesels, weather, sea etc. A long story on these matters in an explanation of the daytank would possibly be confusing for the reader and take the focus from the daytank.

There is one fringe benefit with the water compensating system which we have not touched upon, the hot water sanitary system. From the headertank you have a fourth connection (drain)supplying warm seawater to the galley and the lavatories, see the image below, which I guess is self explanatory. Although the water consumption is fractional it is nevertheless worth while to mention.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2015, 08:10
Don.
Your page 117 seems to be OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2015, 08:32
Don.
Page 199 misprint..... attach periscope....
Checked up to page 237, more than half the Skizzen Buch OK :) 
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 May , 2015, 12:31
Hello Mr. Tore,

I read that they used the economy method for two reasons... 
1.  One diesel was down for repairs so it could not be online
2.  They were on a search grid and fuel was a concern because of a long patrol

I found another instance....
By May 1943 surfacing was fraught with danger, and standing orders from Admiral Godt (who took command of the U-Boat Arm when Donitz became C-in-C of the Navy) instructed captains to run on the surface with the U-Boats in neutral buoyancy, with one diesel and one electric motor running, and to be ready to dive at all times.

It looks like times were getting pretty desperate...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2015, 01:11
Don.
As mentioned many times before, operation of a submarine have many options both with regards to using the flexibility of the systems as well as sailing the boat in the best possible way under different circumstances. That takes skill and experience. However when you shall explain systems related to fuel consumptions I guess normal circumstances should be the reference. An easy way of doing that is by using the engine specific fuelconsumption. Down below I have put up a graph showing the specific fuelconsumption measured on the test bed for a VIIC GW engine. The waterbrake follows the propeller law. The red graph is the non supercharged range of the engine and as you see the lowest possible specific fuelconsumption is 180/g bhp hour achieved at app. 380 rpm and slightly in excess of 800 HP. The specific consumption is then about the same until you increase the rpm to app. 425. and 1000 bhp, then you got to switch in the supercharger and the efficiency of the engine drops (the Roots blower take a lot of energy) the specific fuelconsumption, yellow graph, is then increased to 188 g/bhp starting to raise further from 470 rpm. This graph can be used when you want to run the boat in a best possible fuelsaving way, however as I said before, there are many aspects in the operation of a submarine, fuelconsumption is only one of them..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2015, 02:44
Don.
Skizzenbuch page 261 misprint ....attachperiscope.... page 262 misprint .... from the sten... . In your description of the periscopes- hydraulic may be it is worth while to mention the importance of having the periscope resting on the bottom stoppers while going deep. The reason for that is to releave the stresses on the wires. In the unlikely event of a cable snapping while the periscope is up, you`ll have an unarmed "torpedo" ramming the pressurehull bottom. Otherwise at f.i. 25 meter, the raising and lowering of the scope was an elegant way of adjusting the trim, when you only needed minor adjustment, by using the displacement of the periscopes as an adjustment tool.
Your skizzenbuch is checked OK up to page 274.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2015, 00:55
Don.
Skizzenbuch. Page 247 2nd. lowest line misprint ..... toiled......
I have not checked the pages 277 up to 321 on the torpedoequipment.
On the ballast tanks and venting you are using a lot of drawings from U-historia, nominating the various items. I guess when you translate German into Spanish and then to English you might get some strange nominations, which deviates quite a bit from expressions and nominations previously used in your book. This can be confusing to your readers, moreover in the submarine language it is vital not to use different names for the same item. Examples are Divetanks / Ballasttanks, Hydroplanes/Diveplanes,Shut/Closed, Ventilationvalve/Ventvalve, Floodvalves/Kingstons etc. As the naval expressions deviates even between the English speaking countries it become difficult. I guess you have to chose US Navy or RN English.  I fully realize this is not easy when you quote different sources, although the different words might be correct, I guess it is a bit confusing for a reader but definitely cumbersome for the editor to correct. :'(
The venting of the ballasttanks is an important part of a submarine, and you have some excellent images from U-historia, one thing is missing though. On the large handles for the vents of port and starboard MBT 3, MBT 2 and 4 the lockingpins are left out. Just imagine if the Kingstons were open and somebody accidentally grasped the handle. :o  Below is an image of the lockingpins in place.
You Skizzenbuch is checked up to page 340 except the pages mention above.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2015, 23:40
Don.
If the MBT 2 and 4 were in RFO configuration both the gatevalves and the Kingstons would be shut and main ventvalve would`t work, the same goes for the emergency shut of the ventducts. MBT3 venting would`t work if kingstons were shut. Generally in harbour for a longer period, I guess normally all the kingstons were shut. I don`t think the greatest risk would be in harbour.
When at sea the order: "make ready for diving" is given and a number of actions take place to make the boat ready and after that is done an accidental pulling of the vent valvelever could be fatal. The locking pins are simple and quick to remove and is done as a part of the diving procedure. In wartime and surfaced in hostile waters I guess they would be left out all the time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2015, 00:59
Hello Mr. Tore,

I went through a major upgrade to Skizzenbuch as suggested:
1.  I removed all references to the D designation for the Ballast tanks on both text and photos.
2.  The word Dive Tank was replaced with Ballast Tank
3.  The word Dive Plane/s was replaced with Hydroplane/s
4.  The word ventilation valve was replaced with vent valve
5.  The word flood valve for MBT 2, 3, and 4 was replaced with Kingston/s

I corrected page 199, 261, and 262 = Attack and not attach
I added periscope info on page 260
I added warm wash and shower water info on page 247
I added fuel consumption info on page 401

Mr Tore, I am very grateful for your suggestions about cleaning up all the inconsistencies...  If you see any other problems, them please adivse.

Regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2015, 06:06
Don.
Checked your correction OK. A few remarks on page 401. The accurate outputs of the engine are measured on the testbed by having a waterbrake attached, the braking is done according to the propellerlaw. The output measured is the brake horse power BHP, not break.
I do not fully under stand the figures stated in you column: Mid war diesel engine reversing gear was removed. It is of course correct that the reversing gear was removed, but that does not influence the ahead output/rpm range of the engine which is the same as on the testbed graph. It might look as if you possibly show the outputs of the engines without a superharger, but the supercharger was not removed with the reversing system.
 On the direct reversible engines it was not possible to run astern with supercharger clutched in, it could be that you are showing these diesel astern figures.
In that case I suggest you call the column Astern figures for direct reversible dieselengines to prevent confusion, otherwise use the figures in the VIIC manual page 14, A ship info. I General.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2015, 08:51
Don.
Skizzenbuch. Page 402 contains a short description of the thrustbearing, 403 a more elaborate description of same do you want both? Page 404 shaft break......- shaft brake.....Page 405 charging mode, you can run both engines in charging mode simultaneously as well. Page 406 ...the large red handwheel and the black starboard handwheel...... I believe on the museums U-995 they took fun in painting levers, handles and wheels, red for port equipment and green, not black, for starboard. Looks sometimes almost black on the photos though. Not very important in my time we did`t use these fancy colours. The propeller clutches are named differently, like Main clutch,E-motor clutch , Propeller clutch. The RN expression is Tail clutch, I personally like Propeller clutch. Anyhow as mentioned before, only one name for the thing would be preferable. Skizzenbuch checked OK up to page 410.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2015, 13:12
Hello Mr. Tore,


If running on the surface and charging with both diesel engines, would that be considered a lighter charging mode?  If one diesel engine is dedicated to charging the batteries, then would that be considered a full charging mode?


If charging with both diesel engines while schnorcheling, they still have the 6 knots speed restriction; correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2015, 13:57
Don.
Charging with both diesels could be anything, low speed, high charge or high speed, low charge depending upon the requirement. The advantage is to have the same propellerload  on both propellers which mean you do not have to compensate an uneven load on the propellers by the rudders. Whether or not you have a full charging mode depend on the state of the batteries, what charge you can put into the batteries, you have to reduced the charging at the last part of the charge to prevent gassing and not to shorten the lifetime of your batteries.
6 knots restriction has nothing to do with the mode of charging it is merely a restriction due to the bending forces created on the schnorchelmast.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2015, 00:27
Hello Mr. Tore and Maciek,

I made all the suggested corrections and the one in the Naxos section.  After thinking about Mr. Tore's comments about running both diesels engines and their e-motors as generators...  I was thinking and changed page 405.  I know me thinking is dangerous, but an I correct, or all messed up again? 

I uploaded the latest version of Skizzenbuch to dropbox for your review.  It looks like we are getting to the 400's pages and almost done...

Then I have to re-configure Skizzenbuch's pages for Schiffer, and I'm going to re-configure Skizzenbuch for my leather covered post binder.  I going to change the page layout so I don't need to worry about the binder spacing.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2015, 02:59
Don.
Skizzenbuch page 405. I believe it is OK and I don`t think you should elaborate this further as it could be a bit complicated. Instead of  making a long list of various configurations may be a general description is easier. As previously mentioned the engine performance graph is registered on the testbed waterbrake according to the propeller law. That is an ideal theoretical condition for an optimal propeller, which is useful for estimating vital engine figures. If you put a charge on top of the propeller load you upset the ideal load ( propeller load) and the engine performance both with regards to fuelconsumption and the max. load. I have made a new graph in our testbed scheme showing the max output and an assumed charging load graph (blue) showing how it would upset the performances. Kindly note these are not readings just an illustrating of my explanation. The engineers know how to avoid an overload and adjusting the fuelinjection according to the revs and exhausttemperatures, not by reading tables, as there are so many other variables like hull resistance,(draft and fouling) it is literally impossible to put everything in a list. With to days computers I presume it would be possible to make a programme, but I am that old that I trust human experience and know how before a machine ;) .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2015, 03:44
Don.
Page 404 ...shaftbreak....   Page407   Manual Clutch Drive ..... is to be engaor...... Page 411 ...... Air flow blower: Supercharger..... Mounted on the back side of the engine. Normally we refer to the back side of the engine  as towards the boardside ..We would say the supercharger is fitted on the aft end of the engine...
Checked OK up to page 412.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2015, 06:16
Skizzenbuch.
 Page 375. I just stumbled over your remark on running the E compressor submerged due to excessive air pressure quoting Tauchvorschriften. It is a lot more problems than acid problem at the opening of the towerhatch. Overpressure have a negative influence on the human body, all the gauges including the depth gauges showing the wrong depth, the galley cooking the meal at higher temperatures  etc. and  is not desireable in the compartment of a submarine. As mentioned before when diving, leakages occur particularly on the diesel main exhaustvalves which always needed to be ground by the pneumatic motors which are expelling a substantial amount of air into the engineroom, moreover the inside venting of Q and other tanks all contributes to an overpressure as well and so are leakages and drains. All told, there was always an overpressure when diving, which should be taken care of. Hence if at all possible the E-compressor was started. Opening the towerhatch when the compartment had overpressure could come up with suprises, from the CO being shot overboard to the coocks pots and pan starting to boil like crazy. I have mentioned these events before, including a crewman always having a firm grip around the CO`s  ankles in case he had no time to release the overpressure prior to opening of the towerhatch.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2015, 21:18
Hello Mr. Tore,


I corrected pages 404, 407 and 411.  I also added a paragraph with the info you provided about Over Pressure on page 375.  I uploaded the latest version of Skizzenbuch to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2015, 23:42
Don.
Page 411 the supercharger is fitted on the aft side of the engines.  Page 375 the overpressure ....you don`t have to cook at higher temperatures, it is simply that the laws of the thermodynamics makes the water starting boil at  higher temperatures. F.inst. if you put on the coffeepot it boils at 100 degrees C at normal atmospheric pressure, at higher pressures the coffee get hotter before it boils. This can have a substantial effect on the cocks pot and pans, if he has every kettle nicely simmering at an overpressure submerged and all of a sudden you are surfacing and the towerhatch is opened, releasing the overpressure, the pots and pans starts to boil vigorously spilling the food all over the galley :( .

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2015, 00:16
Don.
Skizzenbuch page  413 first generation schnorchel system. On the system sketch the airinlet pipe is coloured blue, however at the engineroom inlet valves on your sketch it is marked as if it enters the ventilation system as well as the diesel air inlet valve. As the text is saying the air enters only via the dieselair intake valve. See revised sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2015, 05:17
Don.
Page 416. Schnorchelmast head  ....... inletcap and the masy..... 3rd. paragraph.......dieselebgine.....   ..... secon dieselengine.... the commander had to surfase.....
Page 418. On the schnorchel raising lowering ram assembly you  see two rods one on each side of the pistonrod. These are the guide rods for the guide shoe taking up the sideforces when raising/lowering the schnorchel mast, see image below.
Skizzenbuch checked up to page 419.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2015, 17:38
Hello Mr. Tore,

I believe I got all the corrections done and I changed out the schnorchel drawing and added the photo of the hydraulic ram.

I uploaded the latest version of Skizzenbuch to dropbox...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 May , 2015, 23:05
Don.
Your corrections seems to be OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2015, 09:27
Don.
Skizzenbuch page 419. I see you refer to the CO of U 995 as the holder of the Knight Cross (Ritterkreutz) which is correct, but yet a bit on the borderline. Hans Georg Hess being the youngest CO ever of a U- boat was on one of his last missions with U-995 February 1945 and sighted a Norwegian freighter S/S Iddefjord of 6300 DWT in the harbour of the Norwegian town Kirkenes, unloading supplies to the inhabitants. At that time the town was recaptured from the Germans by Soviet troops. Allthough his orders were to go after the Murmansk convoys he called in his officers and said: Gentlemen how about an attack a la Prien, suggesting the should sneak into the harbour of Kirkenes and sink the Iddefjord. So they did and they launched 3 torpedoes registered 3 explosions which they recorded as hits. However non of the torpedoes were hits they exploded in the nearby rocks and Iddefjord sailed unharmed a few days later. The sinking of Iddefjord was recorded by the high command and CO Hess got his Ritterkreutz. He was confronted with this some 50- 60 years later at a meeting with some Norwegian merchant naval gunners in Kiel and answered he had been convinced he had sunk the Iddefjord.
It is correct that 8th of May 1945 U-995 was at the yard in Trondheim installing Schnorchel that save her from operation Deadlight as she was unfit for passage to Scotland.
Page 421. U 480 2ND. warpatrol. The report is very interesting and correspond to my experience during a 28 days test schnorchelling with KNM Kaura ex. U 995. The underpressure could be a bit unpleasant possibly more that an overpressure. We expelled the garbage in the same way by the torpedo tube without a piston, however we did not use cans, but bags which sometime bursted and fouled up the torpedotube much to the torpedopeoples dismay.
I have put up a table in order to visualize the effect of the pressure fluctuations by showing the changes of water boiling temperatures. The yellow parts are the normal underpressure and the green part the normal overpressure. Red are the figures at normal atmospheric pressure.
Skizzenbuch checked up page 423.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2015, 23:39
Don.
Pages 425 to 441 not checked, pages 441 up to 444 checked OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 May , 2015, 00:28
Hello Mr. tore,

I had to change the write-up on page 376; the gas law would not actually work for the boiling point of water with changing pressure.  I found a formula on the internet:

Boiling Point = a constant (K = 49.161)  x Ln  [pressure(in Hg)] + 44.932

This seems to be very close to the chart that you posted.  I used the chart and changed the text because I didn't want the reader to attempt the formula (which I did not include), and use the Windows scientific calculator to check the results.  In addition, I found some very interesting info on under pressure when running with the schnorchel.

I uploaded the latest version of Skizzenbuch to dropbox. Please advise

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2015, 00:48
Don.
I agree, the use of water in the demonstration of the ideal gas law is not very wise, as you see I deleted yesteday the formula.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 May , 2015, 01:23
Don.
I checked your page 376 and think it is better. On a RN submarine the schnorchel float valve would shut and not close :D .
When mentioning the the battery electrolyte, this was of course one of the vital elements in staying submerged. Every morning and evening the chief electrician measured the specific gravity of the battery electrolyte and wrote the figures on a blackboard in the wardroom. We all kept an eye on that blackboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2015, 00:44
Don.
Pages 442, 443,and 456 checked OK and that completes my checking of your Skizzenbuch. As to the Pillenwerfer I can briefly mention that this device was used to launch signal rockets as well, for instance during exercises and in case of emergencies .
I guess a book like yours never shall be flawless being packed with details from many sources of different qualities. Nevertheless it shall be an important source of information for people interested in submarines generally and the VIICs particularly.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 May , 2015, 08:04
Hello Mr. Tore,

Thank you for all the effort you have put into guiding me with Skizzenbuch in the current form.  I have to create a version for Schiffer Publishing with all the special characters, and one for my Leather post binder which is just a 1.75 inch binding side offset.  This is just a conversion process now that I have a final version in hand.

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 May , 2015, 08:41
Don.
Wishing you good luck with your next step.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 20 May , 2015, 06:06
Hi Tore,


just another question: Did you use the Enigma-Machine for coded radio transmitting on "Kaura"?


In a a tv documentation I saw a few years ago it was reported that the Royal Navy gave the Enigma Machines to there allies (for example India) with the evidence that they never cracked the code (as an quality attribute). From then on the Royal Navy was again able to read along the radio transmission. Unless I'am mistaken this secret was uncovered in the nineteens by the RN themselves.


Thanks and regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 May , 2015, 07:35
Falo.
This is a bit off my line, but I don't think we ever used the German Enigma Machines. As in my time we were member of the NATO having its own standard of Crypto- and Cipher systems of which I don`t know very much. I guess the bases for the German crypto-/cipher machines was developed at the end of WW1 and commercially available in the thirties. I presume the Enigma has been refined many times since then. I should assume the value of revealing the German WW2 Enigma system was not the system as such, but rather to keep the news about the revealing secret so the Germans continued to used the same system unchanged. But as I said this was definitely not my field.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 20 May , 2015, 09:41
Hi tore,


thanks for the information. Certainly you are right with the NATO standard. Funny to mention that during my army days in the mid eighties as a combat engineer I was also in touch with radio transmission and field telephone but I forgot all that NATO stuff until your answer. Maybe embarrassing to say but I thought always Norway was neutral as Sweden during the cold war. Sorry for that wrong conclusion   ;)


Thanks again and regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 May , 2015, 11:09
Hello Falo,

If you are interested in the Enigma, then this youtube video may be of interest.  It tells the story of the Bombe development by the National Cash Register Company (now the NCR Corporation) after the German Kriegsmarine went from the 3 rotor to the 4 rotor Enigma machine.

https://www.youtube.com/watch?v=v33IPQwKFKY (https://www.youtube.com/watch?v=v33IPQwKFKY)

I started working for NCR back in February 25, 1963 and retired on April 1, 2009, after a little over 46 years of service.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 22 May , 2015, 04:18
Hi Don,


thanks for the interesting youtube link.


Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2015, 07:36
Don.
I had a quick glance on your latest Skizzenbuch page 341 dealing with the venting of the MBT 2 & 4 port and stb. The residue venting valve for MBT2 port and stb. is named on your drawing as aux valve. I suggest you use residue venting valve. Likewise the emergency shut off valves for MBT 2&4 port and stb are named as ventilation valve , I suggest you name same emergency shut off valves to prevent confusion. The same goes for the emergency shut off vent valves for MBT 3.
The venting system is one of the prime systems on a submarine and the VIICs have one of the most extensive mechanical operation systems for ballast tank venting. For a quick operation of the MBT 3, 2&4 the venting of these tanks are done by large pull- push levers in the control room. The mechanical rods and links for these vents might be a bit complicated and I believe some of the drawings shown are not 100% correct. At the order Dive,Dive, Dive the levers are pulled down opening the ventvalves and as soon as the air has escaped, the vents are shut  by pushing the levers up in a more or less horizontal position. On plate 28 and the U historia drawing for some reason the shut position is shown with the levers down. In that case the levers would be an obstruction for the crew under normal circumstances. Normally they are up shut as on the museums U-995.
Down below I have tried to explain the open/shut position of these very important vents.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2015, 12:34
Hello Mr. Tore,


I have had an issue with the Vent levers ever since I seen both the u-historia.com drawings and the original German Plate 28!  Below I have redrawn both Ventilation levers...  What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jun , 2015, 13:01
Don
Somehow it says I am not allowed to enter ( enlarged) the image, but the way I see the small image it seems to be OK. In order to explain the details of this intricate rod and lever system I have made a sketch showing the principle, rather than the correct angles and length of the levers /links. May be it is selfexplanatory
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2015, 23:50
Hello Mr. Tore,


Actually your previous composite diagram was very helpful to me to get an understanding of hoe the ventilation lever works within the ventilation bridge casting. 


1.  I colored the vent valve drive plate red - it has two studs which are yoked by the 2 drive links in blue.
2.  When the ventilation lever is pulled down, the upper and lower drive arms move as one because of the common link between them.
3.  The lower drive arm swings outward pulling the valve drive shaft downward.  The drive plate studs riding in the bridge casting side raceways assure the shaft is pulled straight down, and not off to the side and the vent valve is opened.
4.  The locking pin is inserted into the holes in the ventilation bridge casting in front or the joint where the drive links are connected to the lower drive arm.  The pin will stop the lower drive srm ans conversely the upper drive ard and ventilation lever from moving.  There is no hole in the drive links for the locking pin ( this would be a point of weakness.


I updated Skizzenbuch with this information as well as all your suggested corrections to the u-historia.com drawings and the latest version is in dropbox...


Regards,
Don_. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2015, 00:57
Don.
I guess the latest correction in your Skizzenbuch is OK. However on page 339 you are referring to MBT 2,3 and 4 stating  the hullvalves are normally open at sea and these levers are used for initiating a dive for these tanks. I suggest you change the text to: the Kingstons ( Flutklappen) are normally open at sea and the ventvalves are shut by the levers immediately after the ballasttanks air has been evacuated.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jun , 2015, 23:25
Don.
I guess you correction is OK, however I wonder what you mean by .....(MBT 2 and MBT 4 floodvalves are normally open as well)... MBT 2 and 4 are as you know saddletanks and in RN English we usually call the floodvalves for these tanks the same as for MBT 3, Kingstons. Kingston valves, named after an English engineer John Kingston who died mid 1800,  were used for any type of ship hull flooding valve, however in the RN submarine language it became the nomination for the ballast tank floodvalves.
Whether or not you should name the ballasttanks by capital letters I really don`t know. I usually indicate the ballasttanks by capital letters for some reasons. Anyhow I agree you should standardize the names whatever name you use.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Jun , 2015, 23:54

Hello Mr. Tore,


I really apologize for wasting your time.... I was attempting to convert some of the Skizzenbuch files and Word keeps crashing and corrupting my files.  So I have removed all applications from my computer except for Word, and hopefully I can get this mess straightened out.


1.  I have changed the text on page 330
2.  I changed the header and text on page 339
3.  Page 340 - corrected the top left drawing - Ventilation lever up to match the valve position
4.  Page 340 - corrected the lower left drawing - ventilation lever up to match the valve position and renamed the valve to Emergency Shut-Off Valve
5.  Page 340 - corrected the lower right drawing - redrew the ventilation valve to the open position to match the lever
6.  Page 340 - corrected the text in the 2 paragraphs
7.  Page 341 - used your drawing that I modified
8.  Page 341 - corrected the text in the lower paragraph
9.  Page 342 - corrected the drawing to indicate a "Residual Vent Valve," a "Emergency Shut-Off Valve."


I have uploaded Skizzenbuch to dropbox for your review.  It is very important for me to get through this review process with you.  I have been reading through some of the earlier pages and I can see as my education evolved and some of the old stuff was just terribly written.


One question...  In order to start standardizing words;  Should it be 'MBT 3" or "MBT3" without the space for all the tanks?


Kind regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Jun , 2015, 23:57
Hello Mr. Tore,


The flood valved for the saddle tanks are normally open during a war patrol; is that not correct?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Jun , 2015, 23:58
Should the Saddle tank flood valves be called Knigstons too?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Jun , 2015, 01:52
Hi Tore,

The flood valved for the saddle tanks are normally open during a war patrol; is that not correct?

It depends on the current function of the saddle tanks. If saddle tanks are used for fuel storage, the flood valves are shut. When the fuel was used, tanks are converted into ballast tanks - the gate valves in the vent ducts are opened, the vent valve levers are unsealed and the flood valves are opened.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2015, 07:16
Don.
If we leave out the saddletanks in the fuel bunker configuration where the saddle tank Kingstons are shut all the time, the saddletank Kingstons in ballast configuration are normally open as for the MBT 3 during war patrol. The Kingstons are time consuming to operate, and you want to be able to dive quickly.
As I mention previously  in the RN English we usually call all the MBT floodvalves for Kingstons, including the saddletanks floodvalves, so if you choose to use RN submarine English in you Skizzenbuch, I guess you should use that nomination. Otherwise sometimes Kingston were used in surfacevessels for several hullvalves, but for submarines only for MBT floodvalves.
I usually use MBT 3 with space but cannot guarantee this is 100%  correct. Anyhow in order to prevent confusion stick to the same language throughout the whole book being aware that the US submarine language is most probably deviating to some extent from the RN English.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jun , 2015, 07:23
Don.
I have  checked your text and sketches on page 340 through 342 and I think your text is better and easier to understand. May be you should skip the ventilation levers for the ventlevers, as we normally use vent  for ballast tanks venting and ventilation for the compartment ventilation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2015, 02:50
Don.
My post (sketch) no 2716 of June 4 Th was not very good, showing only how the rods and levers worked, but they were all drawn in different and wrong positions which might be a bit confusing. I have tried to correct this by the sketch below showing MBT 2 & 4 stb assembly. As you probably have noticed there is a slight deviation between the A bracket for the vent valve of MBT 3 and MBT 2 & 4. this does not change the working principle for the two assemblies which are the same.

I made a bad mistake not mentioning I made use of Simons excellent drawings below to show the position of the stb ventvalves outside the pressurehull. My sincere apology Simon.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jun , 2015, 12:50
Tore, how did the German's seal the rod that went through the pressure hull? Was there a series of O-rings?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2015, 14:55
Simon.
I am  very sorry making a bad mistake not mentioning I made use of one of your exellent drawings in showing the position of the ventvalve for MBT 2 & 4 stb outside the pressurehull.
Kindly accept my apology for this regrettable mistake.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jun , 2015, 15:05
Hi Tore

No worry and you do not need apology about the using my drawing. What is why I do them so people are use them.
 
It was not what I was writing about. It was "How did the German's seal the rod that went through the pressure hull? Was there a series of O-rings?"
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2015, 15:29
Simon.
I don`t think there is a O ring packing box, more a conventional stuffing box with a laternring having a greaseinjection and gland.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2015, 15:40
Simon.
I guess more like the box below.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Jun , 2015, 15:52
Would the packing be wood?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2015, 00:04
Simon.
I don`t think so Simon, wood like Lingnum Vitae is usually used in heavy loaded rotating shafts having submerged bearing like propeller shaft. For smaller spindles like valvestems etc having reciprocating movements stuffing fibers like shown below are cut into excact length to fit the circumference of the shaft, you don`t wind it around but each "ring" are separately placed on top of the other having the cut on different place for each ring. The fibermaterial could be of different materials, even asbestos and "impregnated" with graphite. Having a lantern ring between the two stuffings allows grease to be injected both for sealing and lubrication of the reciprocating shaft.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2015, 01:34
Simon.
Knowing your likings for small details here is the greasing details. The greasing of the stuffingboxes was done by a grease gun to one common grease nipple serving two stuffingboxes as shown on the image below.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2015, 05:27
Simon.
You are a snowman getting you master on snow, make a living working with the snow on the southern hemisphere and going into your winter season,we are in my part of the world still figthing to get rid of the thing. We still have snow which shall last for months. Below is an image taken last week from the highway between our two major cities Oslo and Bergen crossing the mountains. The snow is still up to 11 meters and yesterday they had to dig out one of the skiing slopes as they couldn't find the skilift. So if you need practice come to this area. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jun , 2015, 12:57
Hello Mr. Tore,


Why don't they ship some of that snow to the US West coast?  California is rationing water use right now; Maximum 10 minute shower and 1 per day per person, and the lawns are not to be watered/just burn out.  The population kept on increasing and the environmentalist would not let then build water reservoirs because there was a smelt (snail darter) found down stream that was endangered 25 to 30 years ago.  Last year they found one snail darter in the entire river basin that dumps into the pacific Ocean.  Now about 75% of the Sierra snow melt dumps into the pacific Ocean while California burns out...  This country is all screwed-up with environmentalist and political correctness idiots gone wild!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2015, 13:35
Don.
Our dams are overfilled and all the snow would create an unbelievable flooding with spectacular waterfalls and possible damages. When all that meltingwater is ending up in the fjords it creates an interesting situation from a submariners point of view as numerous of layers of water with different salinity is acting like an Asdic mirror,a dreamarea for a submarine CO to exercise and practise hide and seek play. ;)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jun , 2015, 13:55
Tore,
I'm still here  :)
There was a gap between the periscope tube and the opening hole/shaft (the open tub like thing on the bottom of the command room) when the periscope in the command room was retraced right?


I guess it is hard to explain but could you describe the sound of both periscopes?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Jun , 2015, 14:00
I forgot that I can quickly show what I mean  ;)







Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jun , 2015, 20:39
Hello Mr. Tore,

Reviewing the text for:

GW Sequencing…

First you open the main starting air supply valve to admit starting air to the cylinder starting valves and the starting air manifold. Then you move the starting handle to start, on a direct reversible engine you pass the "umsteuer" maneuvering position; the run position and nothing happens. The run position is only the venting valve open the others shut. On the maneuvering position, the starting lever has to stay in reverse position in order to start the reversing process.

When the starting handle is in the start position, air is admitted to the top piston on the cylinder starting valves; pushing the rocker arms down to engage the rollers on the starting cams. On direct reversible engines the cams are selected by the ahead/astern handle and the engine start to run on air. When you obtain the proper revs you move the handle to "betrieb" or "run" the valves supplying air to the "umsteuer" mechanism and top of the cylinder starting valves are shut, and the vent valve on the air manifold opens and the spring under the top piston on the cylinder starting valve forces the piston up lifting the starting valve rollers from the camshaft.

Everything makes sense to me except the first paragraph, and the next to the last sentence -- "The run position is only the venting valve open the others shut."  Could you clarify this sentence?  What others shut?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jun , 2015, 23:14
Tore,
I'm still here  :)
There was a gap between the periscope tube and the opening hole/shaft (the open tub like thing on the bottom of the command room) when the periscope in the command room was retraced right?

Mark.
It is indeed an open space between the periscope well and the navigation periscope, however on the museum U 995 they put a cover on the well.
Tore


I guess it is hard to explain but could you describe the sound of both periscopes?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2015, 00:03
Don.
Would the sketch below give you an explanation? The distribution air manifold with valves is encircled in red and showing the valves in run position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Jun , 2015, 00:06
Hi Mark,

There was a gap between the periscope tube and the opening hole/shaft (the open tub like thing on the bottom of the command room) when the periscope in the command room was retraced right?

See attached picture, presenting the control room of HMS Graph (ex-U570). You can see the periscope lowered into the periscope well.

I guess it is hard to explain but could you describe the sound of both periscopes?

Here you can hear the sound when operating the periscope on USS Pampanito (Balao class submarine):
http://archive.hnsa.org/sound/pampanito/periscope.mp3
Her periscopes were also raised and lowered hydraulically.
It sounds quite similarly to the periscope sound in the Das Boot movie.

--
Regards
Maciek


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Jun , 2015, 00:29
Thanks, I know this graph picture but I totally forgot to look on it.  :D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2015, 01:03
Mark.
The sound picture of the periscopes for a VIIC is slightly different and may be variable. The hydraulic system has three large accumulators storing the hydraulic energy and prior to any planned attack this storage was filled by IMO pumps which usually was not necessary to run during the attack, sound picture no 1. The sound picture for the navigation/air periscope is that of an IMO pump running as a motor operating a winch via a geardrive. Sound picture no 2. all told not very high. The attack periscope has two sounds, that of lowering and raising the periscope (very much the same as for the navigation periscope) and the turning of the periscope including the operator which is controlled by foot pedals of the operator and driven by an IMO pump running like a motor via gear assembly. As far as I remember slightly more noisy than the lowering/raising sound and a bit more "whining". Sound picture no 3.
Otherwise I agree with Maciek, may be the movie " Das Boot" gives the best indication.
Down below is the present day U- 995 controlroom with navigation periscope well covered.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Jun , 2015, 02:24
Hi Gentlemen,

while looking for the photo of the uncovered periscope well, among the other photos from HMS Graph I have found some worth of interests.
13.jpg - the vent of the (I'm not sure) MBT3 or saddle tanks starboard. In the VOZM book, it is described as MBT 3 vent.

16.jpg - the vent valve lever of the MBT 3 port

10.jpg, 11.jpg - there are visible two handles for operating the flood valves (kingstons) of the MBT 3. As we know, there were 3 pairs of the flood valves. These handles are inserted into the slots for the forward two pairs (see the picture "flood valves.jpg").

21.jpg - this photo presents the charging the U-Boat HP air flaks (or less likely the oxygen flask). This photo is quite similar to the photo published in the VOMZ book, but is taken under quite different angle, so more interior of the magnetic compass casing is visible. What is interesting here, are the visible handles of the emergency blowing manifold. You can clearly see the handles with thickening for easier recognition by divers (see the picture "emergency blowing manifold.jpg").

Don, I think you have to revise picture on the page 218 in your Skizzenbuch and move the ovals, which marks the location of the emergency blowing manifold to the magnetic compass casing.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2015, 06:21
Maciek.
Interesting photos, 11 shows the timeconsuming operation of the MBT 3 double kingstons and 13, I agree, must be the ventvalve of MBT 3 stb. 16 shows a different view as well as giving a better understanding than the overpainted assembly from the museum U 995. Thanks a lot.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jun , 2015, 17:45
Hello Mr. Tore,


Just to verify my insanity... Would the posted drawing ID Tags be correct?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jun , 2015, 19:06
Hello Mr. Tore,

Would you please elaborate about operating the Kingstons for MBT 3?  There looks to be 2 locations in the forward control room floor (1 on each side of the keel) to operate the dual Kingston valves, and there looks to be a smaller opening for a grease gun to lubricate the valves drive structure.

I believe there would be 2 locations in the aft control room floor (1 on each side of the keel) to operate the single Kingston valves, and I would assume the same lubrication installation.

1. Once these valves for MBT 3 were set open for a war patrol, was there ever a need, or reason, to make adjustments?

2. How do you know the Kingston Valve were fully opened, was there a hard mechanical stopping point?

Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2015, 23:48
Don.
I guess your question on tagging would be answered by the image below. As far as I know the U-570 still had the rescue/markerbuoy in the casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2015, 00:54
Don.
Your assumption on the aft kingstons is correct. In the center of MBT 3 it is a bulkhead separating port and starboard MBT 3. On this bulkhead the bearings for the kingston rotating operation rods were mounted. The driverods ended in a threaded part, on this part a yoke having a central nut (inside threads) moved axially as you turned the rod, thus moved the Kingstons as shown on the image. In the outer positions the yoke nut have a stop at the end of the travel against the end bearings.
I cannot recall we ever had to adjust the Kingstons and they are either fully shut or fully open. As they open outwards, the seapressure keep the Kingston firmly shut when in shut position. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jun , 2015, 12:09
Hello Mr. Tore,


Thanks for the info...  Do you happen to have a photo of the GW Diesel engine full control panel?  I would like to see the Ahead/Astern Handle...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2015, 14:20
Don.
The photos I have are all of very poor quality. It is really not much visual changes between the direct reversible and the non reversible engines. The reversing handle was removed but the reversing plate was kept at the maneuvering stand. The most significant change was the removal of the large vertical reversing cylinder and the smaller vertical slide valve. On my image below is the removed items indicated.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jun , 2015, 22:41
Hello Mr. Tore,


I'm still having issues with the Reversing Handle....  See my attached photo.  In the Reversing Handle is on the Left side (blue arrow), then it looks like the handles interfere with each other???  However, if it were on the right side (red arrow), then it looks like the handles will work???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2015, 23:32
Don.
I believe you are mixing the fuelhandle with a reversinghandle. As your image shows the ME maneuvering stand of U-995 being non reversible engine the reversing lever is removed only the residue plate and some visible rods are left. On your photo the fuelhandle is to the far left, the starting lever is in centre and the removed reversinghandle is should be to the right.
Se my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jun , 2015, 00:20
Don.
As I have no original photo of the reversinghandle I made one on the U-995 maneuverstand don't forget it is a fake! :D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jun , 2015, 01:10
Hello Mr. Tore,


The last few drawings clears things up for me....  I called the middle handle the "Maneuvering Handle" because on U-995 there are 2 selections "Operate/Run" on the top, and "Start" at the bottom.


On a reversing engine you have; Stop, Operate/Run, Reverse, and Start.  So, The Maneuvering Handle seems to make more sense to me because it's much more than just a starting handle...  Am I wrong?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jun , 2015, 01:51
Don.
I guess it is named starting handle because it primarily operates the valves in the starting air manifold. The other positions for a direct reversible engine are required to engage or disengage the interlocks in the system to prevent major dammages. On plate 29 you see the starting system. I don`t think I would call one handle maneuvering handle as all the three handles are really handles on the maneuvering stand taking part in the maneuver.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jun , 2015, 11:49
Hello Mr. Tore,


After much consideration...  I am going to go back to "Starting Handle" as the  name.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jun , 2015, 12:42
Don.
That`s what we called it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jun , 2015, 14:38
Hello Mr. Tore,


On U-boats after 1943, the hand-wheel for MBT 1 was mounted on the aft control room pressure hull bulkhead.  Do you have any photos or drawings that showed the MBT 1 hand-wheel located in the aft torpedo room?  I assume the change was made to have all ballast tanks controlled from the control room...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 10 Jun , 2015, 23:08
Hi Don,

I guess you are wrong here.The vents of all ballast tanks were controlled from control room from beginning. The remote control for bow buoyancy tank on the forward bulkhead was added later.
The driving shaft for the operating MBT1 vent valve is going from control room to the aft torpedo room through petty officers room, diesel engine room and electric motor room. In each room, to the shaft is attached the driving hand-wheel, for operating the shaft and vent valve when part of the shaft is damaged.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jun , 2015, 04:04
Don.
I fully agree to Maciek  last post. In the aft pressure bulkhead of the controlroom you have two ventwheels. The stb being for the residue venting of MBT 2 port and stb. The rod goes all the way to the engineroom where a 90 degrees bevelgear takes the rod through the pressurehull right up front of the stb. main exhaust blowing valve and then to the two residue ventvalves. The other wheel on the port side  operates the rod to the MBT 1 ventvalve. The rods goes on port side to the engineroom. Just aft of the port main exhaustvalve a chaindrive connect the drive to stb side and the rod goes now on the stb. side to the aft torpedoroom where it goes trough the end of the pressurehull at  frame 0 and the externally to the MBT1 vent..
Both vent wheels are normally operated from the controlroom and the wheels can be locked as for the other main ventvalves levers and wheels.
See my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jun , 2015, 13:33
Hello Mr. Tore,


It was late and I just got things wrong!  The last photos put posted...  Could you provide me with the top photo only of the 2 hand-wheels for MBT 2 Residual and MBT 1 without the remarks because I use Times New Roman type set...


Thanks,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jun , 2015, 14:09
Don.
I guess this shall do.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jun , 2015, 14:27
Hello Mr. Tore,


Super fast...  Thank you!  I just notices something - The diesel maneuvering panels have the levers arranged differently on the port and starboard side.  They simply moved the fuel and starting lever assembly from one side to the other, but that changes the location relative to the center walk-way (They are not Mirrored).  They have the reversing lever on the inside of the moved assembly next to the starting air hand-wheel.


I was getting confused (very likely) when you posted the photo showing the reversing lever on the left of the fuel and starting levers, and my photo showed the reversing location to be to the right.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jun , 2015, 14:46
Don.
You shall find this done with a number of items on the engine f.inst the fuelpumps which are the same. This is much cheaper to produce and you have only one item to keep as sparepart on board.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jun , 2015, 00:39
Hello Mr. Tore,


My understanding of reverse...  If the engine was running forward, then you stopped the engine.  To go in reverse, you select reverse with the starting lever, and then move the ahead/astern handle to astern and once the cams are shifted you move the starting handle to start. at this point the diesel engine can run in reverse.


Now we stop the engine again.  To go forward again you move the starting handle to reverse again.  Now you can move the ahead/astern handle to ahead.  Once the cams are shifted, then you can move the starting handle to start and away we go in forward...


I know I skipped a lot of details, but I just want to know if I have a basic idea as to how it works...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jun , 2015, 01:22
Hello Mr. Tore,


The attached photo shows the panel on the other diesel engine and the Ahead Astern unit has a very wide space from the other levers.  That way the ahead/astern and the fuel lever handles can point toward earh other still and not interfere with each other.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2015, 01:59
Don.
If you want to simplify the description of the reversing system, may be you could use a text like this:
The starting handle has four position 1. start2. run3.  stop and 4. reversing. These different positions are necessary to release and engage the various interlocks in the reversing/ starting system.
The start position allows the starting air to enter the cylinders, and when the engine runs on air, the fuelhandle is moved to run to allow fuel to the cylinders. When the engine is running on fuel, the starting handle is moved to run position shutting the starting air to the cylinders. The startinghandle in  stop position locks the system when the fuelhandle is put to 0 fuel.
The reversing is done by placing the starting lever in reversing postion thereby engaging the starting interlocks,  releasing the reversing interlocks and admitting air to the reversingcylinder slide. When the interlocks are released they allow the reversinghandle to move into the ahead/astern position and the reversing cylinder is shifting the camshaft in the required position, when this sequence is completed,the starting interlocks are again released and you repeat the starting procedure in the new direction of rotation.
This description is not complete but gives a rough idea of the starting/ reversing procedures.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2015, 00:42
Don.
Your "discovery" of the maneuverstand not being mirrored touch upon an interesting subject. Modern warfare is depending upon access to rawmateriel, people and industrial capacity. The Nazi Germany was limited in all and in the submarine construction details you might find clever details to come around their problem. The most common submarine engine was built in two versions, 6 and 9 cylinder using as many interchangeable components as possible. This was done by making symmetrical parts which could be assembled 180 degrees avoiding mirror ( two) executions in a twin engine installation. For instance the large items as the cylinderblocks were made in 3 cylinders symmetrical units. The same casting could be assembled in 2x3 units= 6 cylinder units for the VIIC and 3x3 units=9 cylinder for the IX, being symmetrical they could be turned 180 degrees and used both as a port and stb. engine. On the image below you see the U 995 6 cyl. engine connectionflange for the two 3 cylinder blocks. Between the blocks there is an inch visible gap between the cylindercovers because of the extra space required for the cylinderblock flanges.
For the fuelpumps they followed the same system. One type of fuel pump for port and stb. engine, not mirrored on the other engine, but simply turning the fuelpump 180 degrees. By that you face  a problem as the fuelplunger is controlled by an axially movement of the fuelrack and by having the maneuverstands on both engines up front and governor in the aft you have to change the direction of the fuelrack movement on one of the engines. On the port engine the fuelrack moves aft to increase the fuelinjection on stb engines it moves fwd.
The movement of the fuelhandle and the hydraulic governor are the same on both engines, a change of the fuelrack direction is done by introducing and extra lever in the rack linkage for the fuellever and the governor on one of the engines.
The whole engine is full of such solutions, like on cylindercovers, supercharger etc. etc. and means a vast saving in production and storage.
On the raw materiel you see substitutes for brass and nickel alloy. F.inst on the U 995 all the text plates on the maneuvering stand are a very dull aluminium instead of brassplates, even the gauges have in some cases substitutes for brass.
I remember during "WW2" all the nickel- and coppercoins were withdrawn from the circulation and substituted by iron and zinc and all the brass ashtrays and handles were removed from the streetcars and trains to be used in the German warproduction.
May be difficult to understand today, but dead serious in my younger days and, as you see ,an impact on the submarine constructions as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2015, 12:17
Hello Mr. Tore,


Thank you for the information about the construction of the Krupp GW Diesel engines...  I have been working on the Schiffer version of Skizzenbuch; compressing pages and adding some of the great info provided by you lately.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2015, 19:28
Hello Mr. Tore,


Skizzenbuch page 411 - the Roots Supercharger - The yellow pipe supplying air to the cylinders - Are there 6 pipes for the Type VIIC Krupp GW Diesel engines, one for each cylinder?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2015, 00:14
Don.
The air supply to the cylinders goes via separate ducts for each cylinder. The system works as follows: When the engine is on moderate load e.g. Roots blower not engaged, the air is sucked in by the engine via several inlets on the common air manifold. From the manifold the air goes via separate airducts to each cylinder.
When the Roots blower is clutched in, the clutchhandle simontaneously turns the rotating valves at the separate normal aspirated air inlets on the manifold, shutting the inletvalves and the compressed air is supplied via the separate air inlet for the Roots blower being compressed and then discharged to the airmanifold.  The compressed air is then supply to the cylinders via the separate airducts. Down below I have tried to make an image using one of Simon exellent drawings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2015, 08:25
Don.
Another important large item is used on both starboard and port engine. The cylindercover, which is designed with starting valve, fuelvalve and safety valve in the centerline thus the cover is symmetrical to this line. However on the 180 degrees turned cover the exhaust and inlet valves  change places. This is compensated by having the valves in cages, a seawatercooled cage for the exhaustvalve and a noncooled version for the inlet valves. The outside construction and dimensions are the same for both versions and they fit in both corresponding pockets in the cylindercover, however the coolingwater outlet from the cylindercover to the exhaust valvecage must be replaced on the 180 degrees version. This is done by having two coolingwater outlets symmetrically placed on the cover, the outlet not in use, being blanked off by a blindflange. Various smaller pipes as venting- and lubrication pipes are adapted as well, but the idea of having one cover fitting both engines is obtained which simplify the sparepart storage (and cost).
Down below is an imaged where I am trying to explain the system and again using some of Simons images.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2015, 08:47
Don.
I realise may be the outlet coolingwater from the cylindercover to the exhaustvalve casing might be a bit unclear. Down below is an image which shows the system. The full flow coolingwater from the relevant cylinder enters a regulating valve where part of the water goes to the valvecage the rest to the exhaust manifold. The outlet from the cage enters the regulatingvalve and leave together with the bypassed enginecooling water to the exhaust manifold.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jun , 2015, 10:01
Hello Mr. Tore,


The drawing you provided has 2 items that I relabeled.  However, when I make the image small enough to upload it's not very readable...


1st item - Super charger clutch handle
2nd item - Foldable starting air handle


Are these the correct label?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jun , 2015, 11:14
Don.
Correct, maybe " foldable starting wheel handle" would be better. It seems as if the quality of the image is not very good, down below I am mailing a new larger image (max. allowable) may be it is better.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jun , 2015, 11:33
Hello Mr. Tore,


Thank you...  The Super charger manometer, isn't that the Exhaust pressure manometer for when blowing the ballast tanks?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jun , 2015, 12:03
Yes Don. This is an old image with a wrong text. The manometers are used for adjusting the exhaust blowingvalves (next to the roots blower) for the ballasttanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jun , 2015, 00:01
Don.
Down below is an image where I have used one of Simons images to turn the stb. main engine cylinder block 180 degrees as well as the fitting of the port exhaustmanifold.
As you see the exhaustmanifold consist of two different parts, when the cylinder block is turned, the cylinder covers air inlets becomes the exhaust outlets. The exhaust manifold aft part, being slightly longer than the other is then placed up fwd to match the new exhaust outlets, thereby the same exhaustmanifold can be used for both engines.
As previously mentioned the movement of the fuelrack is changed when the fuelpumps are turned 180 degrees as well, the direction is indicated on the image. However as you want to have the identical movement of the maneuvering handles for both engines you overcome this by adopting the linkage of the maneuveringstand for on the engines.
 As to the governors and the servomotors, they are not turned 180 degrees and same execution is on stb. and port engine, pretty much as for the maneuveringstand. The governor and servo linkage is adopted to overcome the non turning of the servo as well.  As a description of the system require an understanding of the governor and the servo which might be a bit outside the scope of your Skizzenbuch, but in case you want to go into this details just let me know.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jun , 2015, 22:14
Hello Mr. Tore and Maciek,

As you all know Skizzenbuch is composed of 3 Word document files because of crashing and corruption issues with MS Word and large dot doc files. I have gone through Skizzenbuch in the past few months and reformatted it to a MS Word standard for a 11 x 17 format and ran grammar check and spell check. I have re-sized and edited the photos for the best possible color and contrast within the limits of the original photos.

During the grammar check, I had to change some of the wording to get through the process, but not to any great extent. In the past month, I have amended several pages and added 2 others. The final page count is 459 pages, so I believe Schiffer Publishing will make Skizzenbuck a 2 volume set.

I have uploaded the last 1/3rd section into dropbox, the file name is "Skizzenbuch 11 x 17 - 3.pdf"...

Mr. Tore, would you please check pages 340, 348, 349, and 358 for a sanity check.

Maciek, would you please check pages 397, and 407, and again for a sanity check.

You all are welcome to browse the last third and make any comment. I will work on compiling the new formatted version into one complete file this weekend. That will be the version that goes to Schiffer Publishing for approval. I had to learn how to convert XLS to a DOS Text file, and then add the German special characters for the 34 Plate description pages. I had to learn to create Word columns in a document for several pages, in order to run grammar check on the document (I learned that offsets and simple spacing really screws things up).

After all this, I have to reformat Skizzenbuch again to match their publishing printer standards which does not support any formatting standard, no columns, no tables , etc.  They needed a Word formatted document as a reference.  I will find out in a few weeks how to reformat Skizzenbuch.

This is a real hassle - I can take my PDF version of Skizzenbuch to Office Depot, or Staples and have it printed for my leather post binder with NO conversion.  Their printer is compatible with an Adobe PDF formatted file and several other formats.

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jun , 2015, 00:27
Don.
The lay out looks much better. I have just read page thru 328 thru 337. And have following remarks:
Page 328 ....using ventilation levers..... ventlevers ..... located in the aft controlroom ceiling.... We don't`have ceiling
               on boad ships and particularly not on submarines. Better use upper part of pressure hull.
Page 329 In the list of fueltank capacities you have included the small fueloil collecting tank but omitted the the fuel oil
               daytanks (header tanks) I suggest you include the daytanks as well.
Page 334  .... both handwheels have a lock.... change to both ... vent handwheels ... not to mix up with the ventilation handwheels.
Page 335 .... crank to open and close..... change to shut.
Page 336 ... larger  lever for MBT 2 and MBT 4.. I guess you are fooled by the camera angle as both levers are about the same size. The levers for MBT 2&4 have bends which make it look as if they are shorter. I suggest you use: the aft levers are for MBT 3 port and stb. the fwd levers are for MBT 2&4 port and stb.
Page 337 ....saddletanks kingstons are normally open as well. May be you should add : .. when in ballast configuration.
               U-historia image.  It seems you have Googled the Spanish text, I suggest the following:
                 8  pressurehull. (14a) watergauges for regulating tank 2 and (14 b) regulating and reseve fuel oil tank 1. (15) Trim-, aux bilge and     floodpump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Jun , 2015, 10:55
Hello Mr. Tore,


Do you remember if the Day tank was directly above the Dirty oil storage tank.  If so I can use the same distance from the center of gravity in the table (-9.5)...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jun , 2015, 11:44
Don.
I believe the aft part of the dirty f.o. tank is about 1/2 a frame fwd of the fwd part of the daytank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2015, 11:45
Don.
Skizzenbuch page 340,348,349 and 358. The isometric image on page 341 does not show the centre bulkhead in  MBT 3 thus not the fixing of the operatingrod bearings for the kingstons.
Page 343 image of the bow buoyancy tank marked ventilation valve,.... vent valve.
Page 348 basic starting sequence..... 5. move the starting lever to run .... lifting the cylinder starting air rollers from the starting cams and shutting starting air to                  the cylinderstarting valve.
Page 349 GW Maneuvering Panel Sequencing. I believe you are more or less describing, in different words, the same sequence as on page 348. Suggest you give a condensed ( and incomplete) description of the reversing instead, may be as follows:
Reversing.
Starting lever is placed in the reversing position, this vent the top piston of the cylinder starting valve, lifting the camrollers free from the camshaft at the same time air is admitted to the reversing slide.  The reversing handle is then put in astern position, this movement lift the exhaust-and inletrollers free from the camshaft. The camshaft is now ready to be moved axially. Air is admitted from the reversing slide to the reversing cylinder which move the camshaft axially and placing the astern cams under the valve pushrod rollers which now are lowered on to the cams. As soon as the camshaft is in the astern position, the interlocks are released and the engine can be started now astern as previously described


Coming weekend I shall be away from the internet I hope to be back Monday.
Tore
the push rods rollers can now be placed on the asterncams, the engine is ready to run astern and starting can be done as previously described.


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Jun , 2015, 01:44
Hello Mr. Tore and Maciek,

I made all the changes as suggested, and fixed the 3D MBT 3 drawing...  I have completed the MS Word document where there are no offsets, and I used columns to get everything aligned. I re-indexed the file and had to break Skizzenbuch up into 4 files because the 3rd file got too large and was crashing Word and corrupting the file.  I uploaded the latest version "Skizzenbuch 11 x 17 - M" (M = merged) to dropbox.  This is my final version for Schiffer Publishing, Ltd; Spell and Grammar checked - pending information corrections.

Maciek - I updated the RADAR, Naxos and Wanze section with some new info.  I would appreciate if you would review it and provide any comments.  I believe you are better qualified than I on this subject matter, and most others.

Mr. Tore -  You are the expert on all things that pertains to the Type VII C U-Boat, and I value your opinion and always take your suggestions.

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2015, 02:26
Don.
I started to read the Skizzebuch all over again. Here are my remarks up to page 170.
Page 38 ..negative bouyancy tank.... In RN submarine english this is a word never used, we call it the Q tank, neither do we used the constructed word express, we simply use : blow Q!     
Page 78 .... the pipe to the right is a drainpipe.... It is a hot sea water supplypipe to the galley and the sanatary system.
Page 117 Exhaust port and spark arrestor.  .... and possibly spark arrestor... here is a capital p wrongly used.
Page 123..... or a MAN with a Bachi exhaust.....It is a Buchi exhaust... the u is a german letter having two dots on the top "u
[size=0px]           [/size][size=0px]    .......[/size] The vibration damper... better use torsional vibration damper.
Page 170 The MBT 3 blowing manifold (exterior to the pressure hull)  ..... exhaust blowing manifold ... not to be confused with the HP air blowing                         manifold inside the pressure hull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2015, 07:30
Don.
Checked up to page 176
Page 170 I believe a better image is my new one below.
Page 172 Starboard side ceiling does not exists........ stb. side upper pressurehull.
Page 173  Same as on page 172 ceiling...
               The reason for MBT 3 dual system of venting,kingstons, hp blowing and exhaustblowing is it is a center bulkhead in the MBT 3 thus you have port and                                starboard.
Page 174 Down below is perhaps a better image of the residual venting bevelgear.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2015, 11:06
Don.
Skizzenbuch comments.
Page 177  ...... aproximately 10 meter waterclolumn of fresh..... Possibly better: ... 10 meter column of fresh water at 4 degrees.....
Page 182... the forward and aft hydroplanes are mounted on common shaft... can be misunderstood, possibly better ... the port and stb hydroplanes are mounted on a common shaft...
Page 183....Possibly better: .. the large handwheel on the left is the emergency handcontrol of the fwd hydroplanes and the handwheel to the right, the emergency hand operation of the aft hydroplanes. The normal control is carried out by the electric push buttons on the BBC controlbox in the center of the handwheels.
Page 184...The two diveplane stations... the two hydroplane stations...   .... to manual at the clutch near the dive plane.... hydroplane.
Fuerungsslange mit gewinde- threaded operation rod.  Kreutz kopf -crosshead.
Page 195 ... so when silent running was needed the telegraph could be sill... still...   Last paragraph  I guess you should change this paragraph as the procedure is:  the order is given, the telegraph is set to the order, the reciever acknowledge the order immedeately and then execute the order, thus the reciever do not wait to execute the order before he answer by the telegraph.
Page 196... There are two arrows red and green, not black.
Page 197.. the engineer or electrician will answer ( as mention above) when the order is recieved before the order is executed.
Skizzenbuch up to page 200 checked.
Tore


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Jun , 2015, 03:57
Don.
Skizzenbuch
Page 206 inspection manhole MTB 3 ... this is a manhole in the center bulkhead of MBT 3 may be you should name it : inspection manhole centerbulkhead MBT 3.
The following pages up to 209 deals with the with the  Q tanks. I guess we have discussed it before, but to me using "negative buoyancy tank"for Q is strange, in fact all the ballasttanks are negative buoyancy tanks when diving. It is a long and difficult word which we never used in RN English. Untertriebzelle is a much better German word for the tank and so is Q for quick diving. As you are quite frequently using, to me, the correct name "Q", I guess you should stick to the one and same word in your book. Another word you are frequently using in the following pages concerning the periscope is "wench". I am not familiar with this word, as we in RN English use "Winch". Is it a US word?
I have looked so far through all the pages up to 320 apart from the torpedo pages and have so far not any remarks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Jun , 2015, 02:15
Don.
Skizzenbuch
Page 337.... of the controlroom there are 4 ventilation lever bridges...... venting..   Left image 4 ventpipe- ventilation pipe. 11 Shut off cock.
Page 338[size=78%] ...[/size]Image left  Ventilation of Waterballast.... Venting...Image lower left Driveshaft opening closing- shutting. ... opening closing          lever-   shutting.
Page 339 Venting ...... by large pull-push levers in the controlroom ceiling.... upper part of pressurehull. ..., and ballast tank no 4....ballast and RFO tank no 4.   .... if  the Uboat had any dammage to the airtrunk f.i.by enemy aircraft machinegunfire......
Page 342  Image ventilation valve- ventvalve.Page 343 ..... bow buoyancy tank was located in the ceiling.... upper part of pressurehull. Lower left...eliminating the ceiling mounted handwheel  upper pressurehull.
Page 344 .... with the interlocks in the ceiling ..... aft torpedo room ceiling.... upper pressure hull.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Jun , 2015, 07:34
Don continuing the Skizzenbuch.
Page 347 ... shifting shaft for forward or reverse...  astern. In RN english Reversing means the operation where the engine is shifting either to ahead or astern. Hence you can be reversing the engine from astern to ahead.
Page 349  2nd section 2nd last paragraph ....extra required space required...2nd last sentence ... the gauges having aluminium  was substituted... as substitute ...
k verblockung = interlock.
Page  352....translation of text plate 29 a.  A funny misprint Analassen-Anlassen .
The following pages up to page 400 deals with electrical details which I presume you take care of yourshelf.



Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jun , 2015, 18:15
Hello Mr. Tore,

Thank you for the excellent review work...  For my part, my spelling error was really funny and really stupid!

"Winch" is a mechanical device; as you know...

"Wench" is what pirates called women with loose morals...

and that was not picked up with MS Word Spell or Grammar Check!!!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jun , 2015, 00:02
Don.
I see, I have spent quite a few years in Caribbean waters but never met a wench, put it in your Skizzenbuch dictionary together with Analassen. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jun , 2015, 12:45
Hello Mr. Tore,


Page 337, item 3 on the u-historia drawing is a "Ventilation Pipe" correct?
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jun , 2015, 14:04
Don.
Absolutely, 3 is the port ventilaton pipe. Below I have made an image showing the two ducts stb and port.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jun , 2015, 18:57
Hello Mr. Tore,


When U-995 was caught in the North Sea gale and damaged in 1953; were the emergency shut-off valves used because of damage to the air trunks outside of the pressure hull?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jun , 2015, 23:53
Don.
The damage was primarely done to the casing and the sturdy pipings and ducts inside the casing were intact.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Jun , 2015, 11:30
Hello Mr. Tore,


The photo I had of under the deck has the common trunk missing for MBT 2 and MBT 4...  Was that a result of the storm damage?  If so, then the emergency shut-off valves would need to be used...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Jun , 2015, 14:25
Don.
There are several images of U 995 repairing the casing, however these are photos of the renovation of the museum U 995 end of the 60 ties in Kiel when they removed practically all the pipings and ducts inside the casing prior to making the museum boat. In 1953 after the severe casing damage we ended up in Londonderry and got a temporarly repair carried out on the casing alongside a RN submarine repairship where upon we were able to take part in an execise using the MBT 3. I don`t think we ever took a picture of the damage. Coming home they evaluated the damage with regards to the permanent repaircost and came to the conclusion that a permanent repair would be worth while after all.
 Down below is a photo of the renovation of the U 995 in Kiel around 69-70, as you see they pretty much cleaned out everything inside the casing. I guess your photo is from this renovation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Jun , 2015, 17:11
Hello Mr. Tore,


I assume you meant... "a permanent repair would NOT be worthwhile after all."


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Jun , 2015, 19:10
Hello Mr. Tore and Maciek,

I believe I have completed the MS Word Master Vision (spelling and grammar check, and art lay-out) of Skizzenbuch 11 x 17 - M for Schiffer Publishing.  This version is a guideline for what the lay-out for the book should look like as proposed by me.  The next phase would be to do the layout for the publishing printer which is so different and special character based.

However, I still retain the option to change the Master if there are still corrections to be made.

I have uploaded the latest version of "Skizzenbuch 11 x 17 - M" to dropbox...

Again, I really appreciate all of your help with this project, and I could not have done it without your help!

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jun , 2015, 00:44
Don.
No Don, the damage was that big that voices were raised to scrap the submarine, but after a thorough evaluation  the navy decided to carry out permanent extensive repairs. but after this event she was taken out of service and became later a training submarine and the active crew including me got another VIIC, KNM Kya ex U 926 being only sligthly different from the VIIC/41.

Still some 50-60 pages to double check, however my computer is about to give up, it looks as if some of the prossesors are gone, so I have ordered a new one which shall be ready next week.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jun , 2015, 11:36
Hello Mr. Tore,


OK, I will hold off in presenting a final Wprd document to Schiffer...  Thanks for the update.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jun , 2015, 12:07
Hello Mr. Tore,


Do you remember what year you was transferred to Kya?


I know about computer problems...  I plan on getting a new computer after the 1st of the year.  My dual processor 3 Giga Hz DELL XPS700 is about 9 years old and ready to be donated to the St. Vincent De Paul Charity...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jun , 2015, 12:31
Don.
I was transferred to KNM Kya ex U- 926 early 1954.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jun , 2015, 12:44
Don
I have a HP pavilion dv7 which is a high performance PC having a intel core i 5 prosessor 4 years old. The problem is, in order to keep the price down they sacreficed a lot on the components and the PC is very easy overheating resulting in the prosessors are damaged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jun , 2015, 17:31
Hello Mr. Tore,


I uploaded the latest version of Skizzenbuch 11 x 17 - M with your info about U-995 on page 339.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jun , 2015, 00:53
Hello Mr. Tore,


I sort of did a face lift on Skizzenbuch...  I corrected the titles to present the correct German and English listing.  I removed any reference to Plate, and Diving Plane was changed to Hydroplane.


I have up loaded the latest version of "Skizzsnbuch 11 x 17 - M" to dropbox.


Regards,
Don)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2015, 07:58
Don.
I am struggling a bit working only with one prosessor and am afraid I have to posponed my remarks until I get my new computer. However I discovered an important detail in your comments on the Junker compressor page 97 in the latest Skizzenbuch.  As to the U 570 compressor you mention : .....the airintake was definitely cleaned up and takes less space.....
I guess you have misunderstood the cross section drawing. As I mentioned in my reply post 2494 feb. 27 I did not have a proper crossection Junker drawing so I used the crossectiondrawing of a Japaneeze (Kobe steel) Junker execution which, although having a different airintake, it is primarily of the same design. The VIIC Junker air compressors intakes however are of the same execution for all the Uboats see my image. The difference is the hull exhaustvalves which were modified as the Germans had problems with waterintrusion. On your image of the U-570 installation you see the old exhaustvalves, the outer being almost on the same place as the modified version on the U 995 having interlocks with the vent valve on the aft buyoancy tank. The inner exhaustvalve is, as previously  mentioned, removed on the museum U-995. See my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Jul , 2015, 00:51
Hello Mr. Tore,


Does this image of the Junkers look OK...  The one you provided the text was fuzzy...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jul , 2015, 08:40
Don.
It is a lot better drawing, however it does not shows the air inlet ducts correctly. What is named First stage inlet is the compressor air inlet. This airinlet goes to the diesel combustion air and bouncingchamber as well. On the sketch below I have tried to show the system on your sketch. Air is drawn in via the main inlet air filter. From the filter ducts in the casing the first stage air goes via a branch off to the compressor endcover and is drawn into the first stage compressor cylinder via valves by the inward stroke, filling the first stage cylinder with air. The diesel combustion, scavenging - and bouncing air has a branch off duct in the casing to the underside of the first stage piston where it is drawn in via valves by the outwards stroke of the piston. At the inward stroke this air is forced via another set of valves into the scavenging bouncing chamber and to make it even more complicated, the first 1/3 compression stroke of the first stage compressor piston, deliver air via cylinder portvalves to the combustion- ,scavenging and bouncing chamber as well, leaving only air from the 2/3 of the stroke to the 2nd stage aircompression cylinder.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Jul , 2015, 19:30
Hello Mr. Tore,

I have a problem with the Ju compressor in the way its drawn.  I do not see it working, and here is why...  If the compressor air inlet is on top, then the two light blue chambers must be swapped from top to bottom.  Then when the first stage compressor piston is on a back stroke the valve in the top blue chamber will shut and not force compressed scavenging air out the top compressor air intake.  I have redrawn the compressor to see if you agree???

The 2nd issue is ; how do we get pressurized scavenging air into the bouncing chamber?  My best guess is that there are open ports in the first stage piston wall very close to the piston top, or crown.  When the diesel piston is fully compressed, then the compressor piston would be fully extracted from the compression chamber; the ports would be uncovered in the scavenging chamber and pressurized scavenging air can then enter the bouncing chamber.

I have attached my re-drawing and I will place the input air port on the top of the Ju compressor...  What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2015, 00:35
Hello Mr. Tore,


Here is what I think it may look like....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jul , 2015, 01:01
Don.
If you look at one of my previous drawings may be it explains the air intakes in an other way.
As you see from the image below there is in fact two inlets after the filter one to the top, first stage inlet chamber, light blue on my image, the air enters the inlet valves at the inwards stroke.
 Then there is a second air trunk inlet flange for the combustion, scavenging and bouncing chamber, this air goes into a chamber light blue on my image. From this chamber there are a number of valves the first sets of valves A  leads into the space under the first stage piston, at the outward stroke the piston draws the air in via these valves into the chamber behind the first stage piston. At the inward stroke of the piston the air filling the chamber is compressed shutting the valves A and opens the valves B and C into the scavenging, bouncing and combustion air chamber. The air is now filling this chamber until the piston is on the dead end of the inward stroke. Then the piston start its outward stroke creating a underpressure on the backside of the first stage piston shutting the valves B however the air valves C are on the top (compression) side of the piston and the air is still supplied toe the scavenging, bouncing and combustion chamber until the piston passes the valves C. and the valves C are connected to the underpressure of the piston shutting valve C.


I have tried more than 1 hour to put in the A,B and C on my old image but in vain due to my computer problems. Hopefully you are able to understand my idea without these letters. I expect to have the new computer ready by next week end.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jul , 2015, 05:54
Don.
Finally after 3 hours I manage to get into my photopaint programme, my revised image down below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2015, 12:18
Hello Mr. Tore,

1. The cooling water from the pipe enters a belt chamber around the 1st stage compressor.  Is that correct?

2, The small channel just above the water cooling belt line is the air entrance channel for the Ju and it wraps around the 1st stage piston and connects to the lower chamber and the two 1st stage inlets.  Is that correct?

That was the part I missed and ended up swapping the upper and lower chambers.  I see that was wrong...

Now, everything works for me except the part about getting scavenging air into the bouncing chamber.  It looks like there should be ports cut into the 1st stage piston center column near the piston crown.  That way when the piston is at a full back stroke, the ports would be uncovered and scavenging air could enter the bouncing chamber???

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 02 Jul , 2015, 13:16
Hello again. Tore, did the light inside the boat change when running on battery? Like always turning off "unnecessary" light or was the light always kind of reduced?
It is soon time to create the final light map for me and I think compared to old pictures that the light in "Das Boot" is that dark for dramatic purposes. But maybe the light was changed while making the pictures? It sometime looks like they have some extra light from behind and turned of some glaring lamps.


Can you please enlighten (lol) me about the general light conditions aboard the boat?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jul , 2015, 15:17
Don.
1. Yes
2. The yellow chamber on my sketch below is the first stage inlet air chamber in the endcover and the inlet air is the first flange Yellow dotted circle. The air inlet for the scavenging, combustion bouncing chamber, blue, enters at the the second flange dotted blue circle and there is no connection with the first stage compression air.


The air enters the bouncing chamber ( pink) in two ways, at the inwardstroke from the underside of the first stage piston light pink via valves B and for the 2/3 stroke via valves C, then at the outward from 1/3 compression stroke  via valves C. Valves B are shut.


Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2015, 18:33
Hello Mr. Tore,


When the 1st stage piston moves backward it uncovers the housing for the 4th stage piston.  Therefore the bouncing chamber is exposed to the compressor incoming air. and this air when compressed provides the bouncing effect.  It this correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2015, 22:12
Hello Mr. Tore,


Looking at the Ju stage 2 and 3... 


1. They don't show a connection between the input valve and the lower chamber for stage 2?
2. There looks to be no connection between the 2nd stage compressed air the 3rd stage?
3. How does stage 2 compressed air get into the 3rd stage cylinder so it can be compressed and output to the 4th stage input?
4. There looks to be a empty valve seat at the bottom of the 2nd stage piston cylinder, why?
5. There looks like there is a port at the bottom of the 3rd stage piston cylinder.  That can't be otherwise the 3rd stage piston would be useless?
6. eventually we get 2nd stage compressed air into the 3rd stage chamber, but that chamber also houses the 2nd stage input valve....


Is this compressor a 2 cycle or a 4 cycle compressor?  Really confused....


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jul , 2015, 23:27
Don.
There is no connection between the first stage and the 4 stage cylinder., the only sources for filling the scavenging- combustionchamber are as I mention, the under side of stage 1 piston via valves B and the first stage cylinder port valves C. The 2nd 3rd and fourth stages do not take part in this process.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jul , 2015, 23:58
Don.
From the compressor stage 1 after the piston passes the scavenging portvalves at 1/3 of the compression stroke the air, which from now on do not take part in the combustion process, goes via stage 1 end cover outlet valves into a pipe to the first stage aircooler under the compressor and then to the other side of the compressor where the pipe enters the inlet for stage 2, from stage 2 outlet it goes via pipe to 2 nd stage aircooler and then enters stage 3 inlet by pipe, not clearly shown,  from stage 3 outlet the air goes by pipe to stage 3 aircooler and then by another pipe to the other side of the compressor and stage 4 inlet. From stage 4 outlet the air goes by pipe via stage 4 cooler to the airbanks. Stage 2, 3 and 4 do not take part in the air supply for the diesel section.
The reason for having stage 1 and 4 at one side and 2 and 3 at the other is balancing of the free piston. Each stage has to be cooled before it is passed on to the next stage as there is substantial heat generated by the high pressures the compressor is working. All the 4 tubecoolers are placed underneat the compressor.
The supply pipes to the coolers and between the various stages are not shown on the crossection drawing only the inlet and outlet connections.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2015, 00:20
Mark.
First of all, the ligths were not that bright as on to days museums U 995 as we did not have fluorescent lights. In order not to destroy the night vision we used when needed in the control room and tower, red lights. During nights we usually reduced the lights in the living compartments.
The general lights throughout the boat did not vary during the various running condition.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2015, 01:05
Don.
The inlet pipe  for stage 2 is not shown on the sketch, only the inlet chamber in the endcover.
As stated before it is a two stroke ("cycle") uniflow scavenged four stage opposed free piston dieselcompressor.
Could you indicate on the crossection drawing the items what you are assuming under your questions 4 and 5?
I see I am returning to the bad habit of  including the bouncing chamber in the scavenging, combustion air chamber. As I explained in my reply 2456, page 164 January 18th 2015 it is not really a bouncing chamber, as the major bouncing effect is maintained in the compressor cylinders by the pressure maintenance valve in the HP pressureline. I guess the correct name should be scavenging air chamber which means it is the airsupply chamber both for scavenging and filling of combustion air.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2015, 10:46
Hello Mr. Tore,


When the 1st stage piston moves backward it uncovers the housing for the 4th stage piston.  Therefore the bouncing chamber is exposed to the compressor incoming air. and this air when compressed provides the bouncing effect.  It this correct?


Don.
I don`t think so. Down below I have tried to make an image of the piston in the inward dead end, may be this gives you an idea how it works.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Jul , 2015, 12:21
First of all, the ligths were not that bright as on to days museums U 995 …
The general lights throughout the boat did not vary during the various running condition.


 :) Yes I doubt you used such lamps. But would you say the light in "Das Boot" comes close?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2015, 12:24
Mark.
I dont think the lights in "Das Boot" is too bad.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2015, 20:37
Hello Mr. Tore,
 
I still have a problem understand how you get air into the bouncing chambers… I propose that when the diesel pistons are at full compression that both bouncing chambers have uncovered the internal piston casings and created an opening for air to enter the chambers.
 
If you examine the 1st stage piston and the 2nd stage piston, both have an undercut area on the piston face that rides over the internal piston casing. This undercut provides the space to assure the bouncing chambers are open to air from the external air supply in the case of the 1st stage bouncing chamber, and the 1st stage compressed air supply in the case of the 2nd stage bouncing chamber.
 
If this opening/condition did not exist, then there would be no way physical to get air into these chambers because they both would be sealed.  There are two other possibilities:
 
1. The seals between the 1st stage piston and the 2nd stage housing leaked and allowed air to enter the chamber, but that would most likely negate the bouncing effect as well!
 
2.  There would have to be a valve on the bouncing chamber which would allow air to enter when the 1st stage and 2nd stage pistons were drawing air into the 1st stage and 2nd stage piston chambers.  However, these valves do not exist for either bouncing chamber.
 
I have drawn what I proposed with measurements from my computer screen, and the same could be done with printed diagrams.  This looks to be a working solution to the bouncing chamber air issue.  What do you think?
 
I have attached my measured drawing to go along with my proposal…
 
Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2015, 23:12
Hello Mr. Tore,


I believe I have stages 2 and 3 figured out based on a photo of a compressor and the drawing from u-historia.com.  what do you think?

I believe those different stages of pressurized air pipes run through a water cooling system...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jul , 2015, 00:30
Don.
The U Historia image gives a better understanding of the 2nd and 3rd stage air connections, and each stage outlet goes through a tube water cooler before it enters the next stage. I agree you can use these sketches. After the air passes the four stages tubecoolers there is a pressure maintainace valve. This valve is shut until the pressure is reaching a preset level which I have forgotten, but it is quite high, before the compressor starts to deliver air to the airbanks. This pressure is, as I previously ( Jan. 18th) and repeated in my post 2826 of yesterday mention, creating the real bouncing effect.
 I shall revert to your question on the air supply to the scavenging chamber as soon as I manage to get access to my paint programme.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Jul , 2015, 03:35
Don.
I have tried to illustrate the first stage inlet stroke as follows( sketch below). When the piston is at the outward dead end and start to move inwards, air is drawn into the cylinder at a suction      ( under)- pressure via the air inlet chamber and valves D, this air is coloured yellow, piston position 1. As the underpressure is created, the first stage outlet valves E shuts.The inwards side of the piston is now creating an overpressure ( blue) shutting valves A and opening the valves B and C, supplying air to the scavenging chamber, for C via the dotted blue hatched duct.
 As the piston moves to position 2 the outward part of the piston side has still an underpressure and shuts now valve C as the piston passed the scavenging air ports, thus shutting the  blue dotted hatched connection to the scavenging chamber. The inward side of the piston is having an overpressure, valves B are still open and  in connection with the inward side (overpressure) of the piston, supplying air to the scavenging chamber.
When the piston is at the inwards dead end, position 3, I agree to your sketch showing a possibility of a leakage  from the first stage "piston pocket" however at the dead inward end the pocket is at its max. expansion and there is hardly any pressure difference between the " pocket " and the outwards side of the piston, thus no significant leakage. Moreover  a  possible leakage to the 1 st. stage piston underpressure side (yellow) would be contained due to the sealing  of the first stage pistonrings, the air can only enter the scavenging chamber when the outward pistonchamber pressure open valves C.
The fixing nut for the 4 stage piston rod is sealing the "pocket" towards the scavenging chamber.

Tore                           
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2015, 01:07
Don.
I guess it has been cut, see image below, may be you are confused by the exhaust water trap.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2015, 01:09
Hello Mr. Tore,


It was an optical illusion with the point of view...  I sent another photo showing it was cut...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2015, 11:08
Do.
The images and photos sometimes distorts the dimensions and distances to an almost unbelievable picture, don`t believe everything you see, particulary from the museum U 995 as they have in addition made several changes from the original.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2015, 20:08
Hello Mr. Tore,


I have placed the latest version of Skizzenbuch 11 x 17 - M into dropbox.  I updated the graphics and some of the text on the Junkers diesel compressor pages 92 through 97.


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2015, 02:03
Don.
Skizzenbuch.  A few comments.
 Page 93 2nd last section..... through small springloaded valve in the separating plate... and , for approximately 2/3 of the inward stroke,  via the valves in the beltchamber encircling the first stage cylinder.
Page 94 Bouncing chambers. I guess you should reduce the importance of the bouncing effect of the first and 2nd stage bouncing chambers a bit. As I previously have said the major bouncing, is created in all the compressor stages by the pressure maintenance valve situated  in the HP line after the 4 stage cooler. This valve check that the compressor do not supply air to the banks before an adequate bouncing pressure is built up in the various stages. The pressure is very quickly raised ( as the there is no airdelivery) and is adjustable.  The compressor start to supply air when a lowest pressure in the fourth stage is ,as far as I remember, 170 kg/cm2.
Page 97 The image of the Junker compressor air inlet is a bit different. As we have touched upon before  we have two inlets, one for the compressor and one for the scavenging air, both having common airinlet filter. I have tried to make an updated image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2015, 07:15
Skizzenbuch final checking.
On page 87 second section you are still cursing ;D on the surface.
Page 92. Second section .....connected to the first and forth....Fourth.
Page 339.... are only used if the U boat has been damaged as a result of a aircraft machine gun.....It is used in any event of damage to the ventduct.
Page 443 Diesel engine lubricators.  Right. The lubricators... Left.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jul , 2015, 22:20
Hello Mr. Tore,


1. I hope I have stopped "cursing" on the surface...  Page 87
2. I added your text to page 92
3. I cleaned up the bouncing chamber paragraph and came to the conclusion that the bouncing chamber NEVER goes negative. Page 94
4. I updated the drawing on page 97
5. Page 339, I added your text
6. Page 343, some day I will learn which is Left and which is Right!


I uploaded the latest version of Skizzenbuch 11 x 17 - M to dropbox and I will wait for your OK before submitting this final document to Schiffer...  After this phase begins the tedious process of re-configuring Skizzenbuch for the publishing printer.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2015, 00:34
Don.
I guess your last corrections are OK. It`s probably impossible to get such a publication flawless as you have put together a number of informations from a so many sources. Anyhow I believe your Skizzenbuch shall give a unique contribution to the understanding of the working and operation of the VIIC`s. The book is more comprehensive than any I got hold of when I started to operate the KNM Kaura ex U- 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jul , 2015, 17:56
Hello Mr. Tore,


Thank you for all your help with "Skizzenbuch: The U-Boat Type VIIC Project".... The best thing for me to hear is that the last corrections are OK, because you are the expert in my opinion and your judgement matters so much to me!


I will stay in touch as always.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Jul , 2015, 21:05
Hello Mr. Tore,


I just finished a "Prologue" in the first section...  These two pages and 6 drawings are intended to give the reader just a little of the basics of when diving and surfacing the U-Boat.  I do not cover an "emergency  or crash dive sequence.  I leave that to be covered within the book.


If you would be kind enough to review what I have done, but keeping in mind this is not intended to cover every detail.  In a few weeks, I may have a "Foreword" by Jak P. Mallmann Showell; who has written many books on U-Boats.


I have uploaded the latest version of Skizzenbuch 11 x 17 - M to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jul , 2015, 06:27
Don.
I have read your "Prologue" and have following remarks: IV  Q was normally not flooded only on warpatrols when you expected a quick dive would be nessecary. Thus Q did not participated in the normal dive.
Middle drawing: when the wind deflector on the bridge and the stern is submerged ( not flooded) simontaneously the boat is on the proper divingangle.
MBT 2 and 4... Vented through a common vent trunk..... and there is a ventvalve lever to blow.... vent.
Otherwise I think the prologue is an exellent idea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2015, 13:22
Hello Mr. Tore,


Thanks for the corrections...  I think I got it correct.  The 2 pages are in a column format and I run into spacing issues if I add a line.  So, I combined the center paragraph so I could get things right.  I'm no expert with MS Word columns..


I uploaded the latest version of Skizzenbuch 11 x 17 - M to dropbox..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2015, 18:57
Hello Mr. Tore and Maciek,


I just got an email from Jak P. Mallmann Showell with the following comments....  Should I change all the German words in the plate indexes that end with "sz" to "ß"?

In many places you use the old fashioned "sz" - this was replaced by a symbol looking like a"B" (ß) and in modern usage since before WWII was written as "ss" instead of "sz"

Regards,
Don_


In many places you use the old fashioned ‘sz’ - this was replaced by a symbol looking like a ‘B” and in modern usage since before WW2 was written as ‘ss’ instead of ’sz’
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Jul , 2015, 01:44
Don.
I am not a language expert but to me it is natural to use sz when the other letters are gothic.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jul , 2015, 13:25
Hello Mr. Tore and Maciek,


I sent an email to the U-Boot-Museium in Cuxhaven Germany and receiver the following response...


Dear Don,
since Mr.Monte is not longer on board of our team, but left for family reasons,
I can possibly help you.
In the old times the German language had a "ß" that was a combination of "s" and "z".
Since the handwritten (Sütterlin) letters resembled a "ß", it grew to one separate letter.
But in the meantime resp. since 100 years there is no more written "sz",(it would be incorrect to use it)
but always "ß" when written in small letters, but "SS" when written in capitals,
Messgefäß or MESSGEFÄSS.
We all wish you good luck and success with your certainly very interesting book.

Stay in contact, kind regards
Jutta

 
 Dr. Jutta Baberg
 Deutsches U-Boot Museum
 Lange Straße 1
 D-27478 Cuxhaven-Altenbruch
 
 
 



What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Jul , 2015, 23:12
Hello Mr. Tore,


I had to re-write page 80.  I would like to assure that I have gotten your lesson on fuel tank compensation exactly correct, just stated a little different...


The above diagram is indicating the various valves involved in a fuel configuration of the saddle tanks. As a matter of interest, I made a quick calculation of the weight compensation for the difference between the saddle tanks filled with fuel oil (87% the weight of sea water) versus the saddle tanks filled with compensating sea water. With all 4 saddle tanks filled with compensating sea water the weight increase is about 6.5 tons which then had to be taken from the regulating tanks to balance the U-Boat's weight. In the case of not being water compensating tanks, the empty saddle tanks weight loss would be about 43 tons of fuel which would require an equal weight of sea water to be pumped into the regulating tanks to balance the U-Boat's weight. With a total regulating tanks capacity of 24.6 tons, this would be an impossible task. If you do the same exercise for the internal fuel tanks, the total weight increase by compensating sea water filled tanks would be about 9.2 tons and with the saddle tanks increased weight of about 6.5 tons, the total weight gain is about 15.7 tons and still possible to compensate with the regulating tanks' capacity of 24.6 tons. However, without sea water compensating tanks over all the loss of weight would be about 61.5 tons for the empty internal fuel tanks and about 43 tons for the empty saddle tanks; the U-Boat is now about 104.5 tons lighter which must be compensated. This of course was a play with figures with no realistic use, but is just an example of one of the advantages of water compensating.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Jul , 2015, 01:18
Don.
I guess you got the idea correctly and again this is a play with figures only. The watercompensatings 2nd advantage is the reduction of the free surface effect which might upset the trim. Reverting to your last Skizzenbuch question soonest, but I am having beginners trouble with my new PC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Jul , 2015, 01:59
Don.
Your last question on the Skizzenbuch.
Page V. I have read your corrections and have following remarks: On page V 2nd section you are still blowing MBT 3 by the vent.
Page VI. 4 th. section you introduce the keel as the weight compensating for the loss of the submarine stability. I am afraid it is a bit more complicated and difficult to explain by just a few words. For a submarine surfacing the center center of buoyancy is moving in relation to the center of gravity thereby the metacentric hight is reduced causing a less stable submarine as it surfaces. As you don`t have a chapter of this theortical elements I suggest you only state the fact the the submarine stability is reduced without introducing the keel which might be confusing.
If you are interested in the theory of the submarine stability I can recommend this link: maritime.org/doc/fleetsub/chap5.htm a very interesting topic.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jul , 2015, 18:00
Hello Mr. Tore,


I found a write-up on the Junkers that explains the piston latching in the outer position...


"Starting is achieved by first locking the pistons in the outer dead position, and then admitting compressed air(at about 500 lb per square inch) to the compressor stages. When the first-stage pressure reaches a certain value (between 40 lb and 50 lb per square inch) the latching gear is
tripped and the pistons are flung together."


The key is they admit HP air to the compressor stages and not the Scavenging air box (a miss-read on my part).  I apologize...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Jul , 2015, 00:18
Don.
It is easy to get confused on the Junker, anyhow you found the correct answer. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jul , 2015, 21:35
hello Mr. Tore,


I believe the VIIC/41 has a theoretical crush depth of 300 meters with the thicker pressure hull steel plates.  I have only found that the control room plate thickness was changed from 18.5 mm to 22 mm.  Do you know what changes if any were made to the pressure hull thickness of the other 7 sections?


Also, I checked the photo that you provided of the missing depth gauge from U-995 and I can't make out the numbering, but it looks like the maximum depth indication was 250 meters.  If they dived below 250 meters, then were they off the scale, or was a different meter available that indicated down to 300 meters?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Aug , 2015, 01:00
Don.
I guess the max operating depth for a VIIC/41 was 250 meter hence both the depthgauges,  deep dive- and checking manometers, were scaled to 250 meters. The construction of the pressurehull for increased of max diving depth was mainly due to be able to take evasive depthcharge maneuvres . For the ordinary full circle pressurehull the plating was increased from 18,5 mm to 21mm. The conningtower plating I guess was 32 mm and at the tapered ends of the pressurehull the platethickness was some 3,5 mm less than the full circleplatings. The pressure hull curved endplates were some 35mm , I am not sure how much they were increased on a VIIC/41.
We normally talked about the max. operating depth rather than max. designdepth and if you was at a depth exceeding 250 meters you would consentrate on other problems than the meter being off scale.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Aug , 2015, 13:10
Hello Mr. Tore,


The trumplatte was originally 22 mm thick and I got that info from the drawing Uboottyp VII C - Eisenlängsschnitt (1944) that came with Eberhard Rössler's book "Geschichte des deutschen U-Bootbas, Band 1." I don't believe the tower thickness was changed because the diameter of the tower was not as large as the control room.


However, that 1944 General Plan still shows the control room steel plate thickness as 18.5 mm???


The Germans sure didn't pay attention to the little details in the latter war years... and that is a point of confusion for me...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Aug , 2015, 02:12
Don.
A German; I presume naval architect Køhl, has made a longitudenal drawing of  a VIIC/41 based on, I again presume, a Norwegian drawing (reference Plan 314) unknown to me, where a lot of infos are noted including the plate thickness. I have put up the figures in a table starting from the aft pressurehull frame 0.

  Frame no.         Plate thickness mm                        Distance in mm                       Schuss                         Remarks

    0                         35                                                 0                                         0                               Curved endplate

0-12                        16                                            6000                                           I                             

12- 18 appr.             17                                            3500                                          II

18 app.-27,5             17,5                                         5500                                          III

27,5- 36 appr.           18                                            7100                                          IV

36 appr.-50,5             18,5                                        9100                                            V     Turmplatte mm 22- pressurehull top plate in the tower joint area ( not the towerplating)

50,5-62,5                   18                                           7200                                          VI

62,5-75,5                   17,5                                        7900                                           VII

75,5-81                      16                                           3100                                           VIII     assuming bow curved endplate is 35 mm







The 22mm topplate in the tower area is due to the relative large openings in the pressurehull.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Aug , 2015, 15:40
Hello Mr. Tore,


Thank you for the researched data...  I will add the additional info to Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Aug , 2015, 01:19
Don.
A few comments on the diving depths.

Max. diving depth.
The diving depth of a submarine is often confusing as there are many figures mentioned without reference to what the figure represent.

Ther are generally four divingdepth figures.
1. The designed depth.
2. Testdepth.
3. Max operating depth.
4. Crushdepth.

The desinged depth is the theoretical calculated depth based on material, frames , hullopeneings and other physical factors. In this figures the designer includes a safety factor which even can be as high as 2.5
The testdepth is, as it says, the max. depth carried out at the delivery trials and can vary between  the different navies. In US navy I guess it is 2/3 of the designed depth, RN 4/7 and the German navy 1/2 of the designed depth. These depths are normally the maximum depths which the submarines in the different navies are allowed to operate in peacetime.
Crush depth is the dramatic figure used by fiction and movie writers and represents the figures where the pressurehull actually collapses. These figures may vary even for the same class of submarines and depend on the quality and workmanship of the various shipyards.
I remember we were discussing the terrible waste of Operation Deadlight were the German submarines were sunk at deep waters, listning and recording the depth when the crushing sound occurred. Unofficially I read somewhere that the collapsdepths of the VIICs were  varying between 200 and 280 meters. I wouldn trust those figures.
I don`t believe there are any accurate reliable figures and as I said before we did not spend time pondering upon same.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Aug , 2015, 21:21
Hello Mr. Tore,


I'm in the process of updating the info on the Papenberg depth gauge and I have a few questions.


Q1. The height of the attack periscope from the keel fully extended is 14.663 meters. When the captain orders the U-Boat to periscope depth; that is 18 meters and then the periscope is fully extended and under cut (below the surface).  Then the U-Boat rises and when the periscope is free (above the surface), then that depth is noted. (U-Boat Diving Manual)...


Q2. Is the papenberg water column source located at the bottom of the keel? I'm not sure?


Q3. Setting up the Papenberg - when the U-Boat ascend to 20 meters using the large depth gauge (0 - 25 m), and then they open the water valve to the Papenberg to establish the water level; then adjust the water column to read 20 meters? I would think that the u-boat's internal pressure +/- would make all the depth gauges inaccurate?


Q4. The scale on the left side displays the residual buoyancy/displacement in metric tons.  On an initial trim test I believe the U-Boat has all the MBTs flooded, the Q-tanks are empty.  The tower would most likely be above the water surface. If the Papenberg inlet valve was opened, then the water level in the tube would rise to some point on the left scale.  If they read the level it should tell them how much water needs to be pumped into the regulating tanks to get to the tower deck awash? or would it be to the tower hatch covered? There is a red marked "0" on the left scale.


I have attached a photo of the Papenberg scales.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 04 Aug , 2015, 16:34
Hello Tore,


Command Room of U 570 has a 3rd sight glass, do you know what its function was?


And what are the discs above the depth rudder control good for?



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Aug , 2015, 19:47
Hello VIC20,


The caption below the photo reads as follows...


"Control Room starboard side forward showing diving plane controllers, hand wheels for manual operation of diving planes, diving plane angle indicators, Bourdon tube type shallow diving depth gauge, closed end tube type "attack" depth gauge, closed loop inclinometers (one with coarse graduations and one with fine graduations), and propeller r.p.m. indicators - Case of deep diving depth gauge is shown at right of photograph - A mechanical diving plane indicator can be seen back of each diving plane hand wheel."


It looks like it's a 2nd inclinometer, one course and one fine...  Perhaps, the disks in back look to be the mechanical hydroplane angle indicators???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Aug , 2015, 23:07
Mark.
This is indeed a mechanical hydroplane indicator operated by a wire inside a flexible tube, a so called teleflex system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Aug , 2015, 02:46
Don.
Q1. I don`t think there is any standard attack periscope depth. The attack periscope depth is ordered by the CO and may vary depending on light conditions, sea and other prevailing parameters at the time of the attack. I believe the main thing is to hold the boat stable in relation to the surface letting the CO take the small adjustment himshelf.
Q2 and 3. I don`t see the need for going all the way to the keel for the seaconnection for the Papenberg. As long as you have a submerged connection all the time you shall have the waterpressure variables the same whether it is coming from the watersurface down to 14 meters or from 14 meters down to 28. Remember it is the compression of the air in the bufferchamber which is controlling the watercolumn. The adjustment of the Papenberger can actually be done in several ways, all based on adjusting the airpressure in the bufferchamber. F.inst. by having a cock on the top of the chamber letting air out thereby raising the watercolumn, or as the case of U 995 having a draincock at the bottom of the gauge assembly  draining the water thereby reducing the aircompression (raising the water column).As far as I can see the Papenberger on board present days U-995 has a scale which put a 0 depth at the position where the tower wind deflector is breaking the surface, which means 9400 mm from the bottom of the keel. You can of course use any reference point.
Q 4. On the left scale on the U-995 is a sketch showing the attack periscope with depthmarkings, I am not sure the scale shows the residual displacement tonnes. I cannot recall we used the Papenberger for accurate adjustment of the regulating tanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Aug , 2015, 12:14
Hello Mr. Tore,


Thank you for the update...  The only thing that seems to be a mystery to me is what exactly is the function of the index pointer that slides up and down on the rod on the right side of the Papenberg meter scale?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Aug , 2015, 07:55
Mark the 3rd sightglass is the inclinator eg. the instrument for measuring forward/ aft trim like diving angle and it work as per image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Aug , 2015, 14:55
Thanks Tore and Don, so the 3rd one of the two inclinators is identical to the one in U 995 (which comes with only one inclinator) right? The other Type VII you served on, did she had one or two inclinator gauges?


How did the mechanical hydroplane indicator displayed the angle? I don't see a gauge needle on any of the pictures. Did the mechanical hydroplane indicators always work or only when the manual wheels were used (instead of the electric motors)?


Which raises another question, the manual wheels could be decoupled right? Or did they always rotate simultaneously when a button was pressed on the electrical "BBC" controller?


The only thing that seems to be a mystery to me is what exactly is the function of the index pointer that slides up and down on the rod on the right side of the Papenberg meter scale?


I can only guess but I believe it is a marker which can be set to quickly mark a desired depth. I think this would be useful if the attack periscope is in use. The usable height of the observation periscope was very limited (operators must bend themselves if they want to lower it). So when the observation periscope was in use then the desired depth (to keep the head just low above the surface) was basically always the same. But the attack periscope was usable at almost any extension (at least this is what I understand from the description in Harry Schlemmer's book "Vom Turmsehrohr zum Optronikmast"), hence the "periscope depth" of the boat and the extension of the attack periscope could vary which makes a quick marker useful. But this is just my first thought and I bet I am totally wrong  ;D


Something different that I absolutely don't understand:
The head of older versions of the C/2 attack periscope (till 1942) were pressure proof up to 15 bar only (equal to approx. 150m) later ones up to 25 bar (250m). I think even with a fully retracted periscope the head was still visible and had no additional protection (or is that wrong?). This would mean the older boats could dive to a maximum depth of 150 meters only because above that they would risk an ingress of water through the periscope.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Aug , 2015, 20:24
Hi  Mark,


I will eventually get everyone's name right...  I found a photo that shows a lid placed over the tube casing of the aerial periscope.  I can't explain why, because if the lid is left on and they come up from a deep dive; do they just pop the lid off when they raise the periscope? Perhaps Mr. Tore has an explanation?


Perhaps the lid has a chain attached and they just pop it off the periscope tube casing when the aerial periscope is raised, and put it back in place after surfacing???


The attack periscope is located up in the tower and the captain is seated right in front of the eyepiece (no bending) the upper section of the attack periscope is what is raised and lowered..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Aug , 2015, 08:45
Mark and Don.
On the U-995 and U-926 we used only one Papenberger as far as I can remember. It looks indeed on your image that it is a 2nd. Papenberger with somewhat larger glass for higher accuracy.
The manual operation of the hydroplanes was normally disconnected by a dogclutch situated locally next to the hydroplaneshaft, thus the wheels did not turn. You could connect the mechanical drive pneumatically from the hydroplane operators place, see my image, to reset same you had to do it locally though.
On my image below I have indicated the mechanical pointer of the teleflex system frrom U-570.

I am not sure where you got the pressureproof figures for the periscopes. 150 meters was the 1939-1942 testing pressure for the pressurehull plating. I should certainly think the periscopes could take more than that. Another thing is the operation of the periscopes. If you are going deep you lower the periscope to the endplates relieving the strains on the wires. However sometimes you let the boat hang on the periscopes when you need to go absolutely silent. You shut down the pumps and adjust the bouyancy by lowering and raising the scopes, ( changing displacement) using the stored energy in the hydraulic accumulators. It could be a limiting max.factor on these operations which is rather due to the wires than the scopes.
To my knowledge we never used any pressureproof caps on the periscopes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 08 Aug , 2015, 19:27
On my image below I have indicated the mechanical pointer of the teleflex system frrom U-570.

Thanks, I first thought this is a shadow.

I am not sure where you got the pressureproof figures for the periscopes.

From a book about German Zeiss Periscopes, written by Harry Schlemmer a physicist of the Zeiss AG.
http://www.koehler-mittler-shop.de/Programm-Koehler-15/Vom-Turmsehrohr-zum-Optronikmast-Schlemmer-88.html


However sometimes you let the boat hang on the periscopes when you need to go absolutely silent. You shut down the pumps and adjust the bouyancy by lowering and raising the scopes, ( changing displacement) using the stored energy in the hydraulic accumulators.


Wow, I need to add this to the simulation of the more complex 2nd title  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Aug , 2015, 22:58
Hello Mr. Tore,
Hello Mr. Tore,

While reviewing page 340 and looking at the attached drawing of the threaded carriers to open and shut the Kingston Flap valves in MBT 3, I have come across an issue with the aft drive mechanism. the attached drawing does not provide enough detail about the threaded carriers that cause the Kingston Flap valves to swing open and shut while the threaded carrier moves up and down on the threaded drive shaft.  See my attached drawing. 

Do you have better drawings of these threaded carriers? Especially the aft carrier that only drives 1 Kingston Flap Valve...  My attached drawing seems to answer the issue where the threaded carriers and the attached drive rods have the ability to swing and follow the Kingston flap valve attachment point.  That point, besides moving down also moves to towards the keel.  See where I have marked the poor drawing with yellow circles of the drive rods swinging point. what I need is better details...

Regards,
Don_

PS - The drawing seems to indicate the threaded mechanism may be attached to the internal longitudinal bulkhead in MBT 3 at an angle - where the bottom of the screw drive shaft is further away from the bulkhead and that does make sense???

Does Simon have any drawings of MBT 3 internals?  I know he is great on details and always gets the mechanical stuff correct?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Aug , 2015, 01:06
Don.
Unfortunately I dont`have access to my paintprogramme but I believe the best image would be that of plan 28. The fixing points to the centerbulkhead would be the two endbearings. In beween these bearings is the threaded shaft located. The driveshaft up to the controlroom having two universial joints allows the shaft to operate under an angle rotating the threaded shaft between the two fixed bearings, The travelling nut ,in this case the yoke, moves up and down as the threaded shaft rotates and thus operates the kingstons. I suggest you use plate 28 as an illustration which is more correct than your  present image. I have tried to indicate what I mean on the  image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Aug , 2015, 20:45
Hello Mr. Tore,


Thanks - I updated my drawing and will post it...


I have a few questions about MBT 3.  You stated MBT 3 was nice and clean with a fresh coat of zinc chromate paint and there was a man-hole in the internal longitudinal bulkhead...  How did you get inside of MBT 3?  Through an open Kingston valve?  If that were the case, then why the man-hole?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Aug , 2015, 08:17
Don.
As far as I vaguely remember we were able to squeeze in via the Kingston openings, may be the Kingstons were dismantled. This was some 65 years back and I was at that time a very skinny guy.
I see for some reason you want to have the threaded shaft and travelling nut on the aft Kingstons placed in an angle, I don`t see the reason for that, I believe the threaded shaft and bearings are vertically fitted and the driveshafts having universal joints have an angle.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Aug , 2015, 23:18
Hello Mr. Tore,


OK, what you remember is good enough for me...  I will work on the drawing.  (Done)...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Aug , 2015, 00:35
Hello Mr. Tore,


Sometimes I think too much and forget some of the many lessons you have taught me...


any way...


MBT 3 has 6 Kingston valves normally open so the U-Boat can dive... Right? Why on earth would they ever want to close them?  If on a war patrol with closed Kingston's they can't dive, so they may as well run up a white flag because they can't out gun a destroyer and they would be ducks in a pond for aircraft?


I certainly am missing something... I did think of one thing...  make it a museum U-Boat!


Regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 18 Aug , 2015, 02:38
Hi Don,

MBT 3 has 6 Kingston valves normally open so the U-Boat can dive... Right? Why on earth would they ever want to close them?  If on a war patrol with closed Kingston's they can't dive, so they may as well run up a white flag because they can't out gun a destroyer and they would be ducks in a pond for aircraft?

The Kingstones of the MBT 3 were shut while staying in the harbour - to prevent the boat to submerge accidentally, especially, when the hatches other than conning tower hatch were opened. During the war patrol, the regulations prescribed the Kingstones to be opened.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Aug , 2015, 04:04
Don.
Maciek has already answered your question. I may add in general Kingstons are bottom valves in any ships. For submarines they are vital as Maciek explains, an additional advantage of MBT 3 Kinstons would be if you have a maintenance job on the the vents you are able to do this afloat without having to return to a drydock harbour. On the VIICs you have an additional possibility by shutting the emergency shut off vents in the vent ducts. But think about how easy somebody could pull the venting handle by just removing the lockingpin.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Aug , 2015, 22:01
Hello Mr. Tore,


U-Boats which were declared unfit for sea. U-926 had an over stressed MBT 3 creating structural damage to the pressure hull. This damage was caused by a mistake when blowing the tank by her crew during the end of WWII.


How could they over stress MBT 3?  Did they do a HP blow with the Kingston valves and the vent valves shut?  The only place where the Kingston valves for MBT 3 are shut is in the harbor area. 


That sure looks like the CO or Engineering Officer didn't like the idea of surrender...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Aug , 2015, 23:43
Don.
I never saw the report from the German navy as to the actual cause of the structural damage other than it appeared during a deep dive test in the southern area of Norway early 1945. She was then moved to Bergen where she surrender May 9 th. 1945.
Your remark of hoisting a white flag for surrender is interesting. When the German submarines surrender in Norway May 9th. 1945 ,there were 97 of them,  they were ordered to raise a black flag preferably on the starboard side by the allies when transferred to other locations. I some times have wandered why, because the white flag is international approved by the Hague-Convention of 1899 and 1907 as the official flag of surrender. Could it be the RN would not have a surrender flag which could be taken for the RN`s White Ensign?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 Aug , 2015, 01:22
Hi Don,

How could they over stress MBT 3?  Did they do a HP blow with the Kingston valves and the vent valves shut?  The only place where the Kingston valves for MBT 3 are shut is in the harbor area.

The one way to damage the MBT 3 is blowing it with HP air with the Kingstones shut. As you said, the flood valves should be shut only in harbour area. I can not speculate, if someone could intentionally shut the valves and then blow the tank.

The other way is to blow MBT 3 "too fast" - the Kingstones are opened, but the pressure inside the tank increases because the water can not evacuate through the flood valves fast enough. Theoretically you could calculate the maximum flow knowing the cross-section area of the Kingstones (I believe Mark is good in these stuff). When you exceed this maximum flow, the pressure inside tank can not be released and can damage the tank.

The similar issue is when you blow negative buoyancy tanks - the operators had to carefully monitor the pressure of the admitted air to avoid the damage of the tanks.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 19 Aug , 2015, 01:43
She became an experimental boat in Pillau on 11.11.1944. On 19.12.1945 she collided with U 1131. After repairs in Kiel she became a front boat and was transferred to Stavanger on 1.4.1945, she got attacked by an aircraft on 4.4.1945, due to bad weather (!!!!) she had to stop two times in Kristiansand (4.4. and 5.4.) and once in Egersund (7.4.). She arrived in Stavanger on 8.4.1945 and was sent on 14.4 to Bergen for repairs. On 15.4. she arrived In Bergen and repairs of MBT3 started. At the end of the war she was not transferred to England because she was unseaworthy.



from:
http://www.ubootarchiv.de/ubootwiki/index.php/U_926 (http://www.ubootarchiv.de/ubootwiki/index.php/U_926)
And a search for U 926 on http://historisches-marinearchiv.de/projekte/duikboot/ergebnis.php (http://historisches-marinearchiv.de/projekte/duikboot/ergebnis.php)


Seems it was the result of the attack of the aircraft, it is obvious that they could barely keep her afloat after the attack.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Aug , 2015, 02:11
Mark.
 This is interesting news and a bit more according to the first story I heard, what is a puzzle though is the mentioning of the structural damage to the Tauchbunkers which would mean either MBT 2 or 4, whereas I saw in 1954 the damage in MBT 3 starboard side repaired as well as some dents. I was then told it was due to a depthcharge bomb attack from an airplane, this was later corrected by some documentation from air commodore Derek Wallers to be overstressing by wrongly blowing by the crew. Unfortunately I don`t have access to these documents right now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Aug , 2015, 00:37
In a search for the black flag instructions I came across the surrenderinstruction to the German Uboat and discovered to my astonishment that the Uboats were instructed to fly a large black or blue flag, an explanation why is not given.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Aug , 2015, 18:34
Hello Mr. Tore and Maciek,

Jak P. Mallmann Showell did a quick survey of my book about 3 weeks ago and suggested that I have someone to proof read the book and fix the many issues; German "SZ" in place of "SS," many German words were spelled wrong and missing the Umlaut, etc... I have gone over the German text in the Sheet Indexes and corrected what I believe was missed or incorrect in the original text from uboatarchive.net. In addition, I have corrected some of my many poorly worded sentences.

I have uploaded my latest version of Skizzenbuch 11 x 17 - M to dropbox which will be the printed version for my Leather Post Binder.  This will be printed sometime during the first week of September, and this is what I will take to Schiffer Publishing the next week.  There are several blank pages in the first section for Publisher information and the foreword.

Mr. Tore would you please review the contributors section about you and If you approve, or if you would like to add any personal data, then please let me know, and would you please review page 340 with the changed information on MBT 3.

Maciek, If you would like to add a photo and any personal information about yourself in the contributors section, then please do so.  Your emails and postings on this web site have made a significant contribution to my U-Boat education and Skizzenbuch.

All, Please feel free to make any suggestions or corrections because I would like to get this book published in a version that is near excellent in documentation, and presentation.

Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Aug , 2015, 03:52
How much german is in your book? I could take a look on it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Aug , 2015, 11:21
Hi Mark,


There are about 34 pages of German Text, but the type is in a very large MS Word 18 point format for the indexes and some pages range from 3 lines to about 20 lines.  Not that huge...


Mark, If you send me an email, then I can go to dropbox and send you a link to "Skizzenbuch 11 x 17 - M" and I only ask that you not distribute the PDF because the Book will be published by Schiffer Publishing Ltd. here in the USA with international options.


My email address is donprince5207@comcast.net


If you have time to scan through the book, them please advise me of your opinion and if you spot any issues with the illustrations or text, then please advise me so.  The book is highly illustrated and the text is fairly brief by design.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Aug , 2015, 13:19
email sent
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Aug , 2015, 18:53
Hi Mark,


My wife Maureen and I just got back from dinner...  I went to dropbox and sent a link.  Please let me know I it does not work?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Aug , 2015, 18:59
I've got it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Aug , 2015, 20:49
Hello Mr. Tore,


While I was re-doing your info, I googled "Gosport" and found a photo of an A Class Alliance S67 which looks stunningly like a U-Boat with the sail updated...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Aug , 2015, 00:45
Don.
The "A" class was very different from the VIICs, much larger, 1385 tonnes surfaced 1620 submerged, 85,5 meter O.A. 61 crew, 6 bow torpedotubes and 4 aft, and designed after the Pearl Harbour experience for the Pacific. The dome on the bow is the Sonar.
The CO had his own cabin in a small separate pressurehull next to the tower.HMS Alliance is a very well known submarine to me as she was stationed all the time in Gosport at HMS Dolphin when I was there. The class as such never took part in WW2 as only two submarines were commissioned before the capitulation. The sail came after my time but you clearly see the folded hydroplane very much different above the waterline.
The resemblance of a VIIC might be due to the "A" class bow flare as the Atlantic bow on the later VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Aug , 2015, 07:35
Don.
Skizzebuch MBT 3 Kingstons.
I have read your page 354 on the MBT3 Kingstons. May be you make it a bit complicated and to me it gives an impression the threaded rod with the travelling nut (yoke) is fitted on a atwarthship bulkhead. I guess it is on the alongship centre bulkhead. The greaselines do not have to be flexible as they are fitted to the fixed points bearings on the centre alongship bulkhead. The Kingstons are opened into a recess in the keel, well protected. I have tried to show my idea on the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Aug , 2015, 18:44
Hello Mr. Tore,


I found a photo of the keel being constructed, so I can make a correction based on the Keel structure. Could you post the photo that you used with your drawing?  It looks like the screw jack may be raised a little by the keel structure, so I will redraw and the make a correction and post for your approval.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Aug , 2015, 21:30
Hello Mr. Tore,


Does this drawing look OK?  I added a guide bar in back of the carrier and the reasons are:
1. We don't have the real engineering drawings.
2. You don't want the carrier applying torque pressure on the Kingston drive rods.
3. It only seems logical.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Aug , 2015, 02:41
Don.
I guess you got the idea. I am not sure of your guidebar though, it could be the threaded bar has a sleeve with slots as shown on the image below. This system is used in the VIICs quite frequently on vents and flapvalves. The distance of the threaded bar from the centre bulkhead can be adjusted by putting shims between the bearing pedestal and the centre bulkhead.
I have tried to make a sketch showing the protecting pocket in the keel, my photo of the system does not show the Kingstons as it is an image of the museum U-995 where they have welded plates covering the kingston gate. I guess they don`t want have people trying to enter the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Aug , 2015, 14:07
Hello Mr. Tore,


I agree; there may not be a guide rod, they could have had a guide track welded to the longitudinal bulkhead, or a multitude of ways to keep the carriers from turning; especially since the threaded shaft is exposed to sea water and the threads could have rusted. Making the carriier drive shaft difficult to turn.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Aug , 2015, 20:14
Hello Mr. Tore, Maciek, Mark, and Simon,


I have uploaded the latest version of "Skizzenbuch 11 x 17 - M" to dropbox.  I still have to update the Contributors section with additional info when available with photos.  I have done another English Grammar and Spelling check up to page 122. After I get the German text corrections from Mark, I will be updating the German text as well.


I sent Simon a PM through this web site, and I'm hoping it works.  I would like to assure that Simon gets the proper credit for his excellent drawings.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Aug , 2015, 22:40
Hello Mr. Tore, Maciek, Simon, and Mark,


so far I have reviewed up to page 211 in Skizzenbuch and added the info about Simon. 


Simon, I sent you a link to Skizzenbuch 11 x 17 - M, and please let me know if you have any issues with dropbox. Also, let me know if I need to make any changes to your Contributors entry...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Aug , 2015, 23:22
Don.
I am right now in a remote area of the country having limited access to the net and not being able to download your latest version of your Skizzenbook, hope to be able to get back by coming weekend.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Aug , 2015, 18:37
Hi Tore

I found a little amount of free time yesterday so I took a look at my engine room drawing of the Cooling-water system & anti-corrosion oil-circulating system.

Would the valve ‘e’ be access but a small deck plate hatch or access by removing the whole deck plate?

(https://farm1.staticflickr.com/774/20315023323_8177d56bab_b.jpg)

(https://farm1.staticflickr.com/705/20314052673_1999f3c367_b.jpg)
Fig. 1. Red circle is the location of valve ‘e’ below deck.

(https://farm6.staticflickr.com/5711/20314589363_cd8b7f7128_b.jpg)
Fig. 2. Red circle is the location of valve ‘e’ above deck.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Aug , 2015, 18:48
Hello Mr. Tore, Maciek, Simon, and Mark,

I have Grammar and Spell checked Skizzenbuck up to page 275 and posted the latest version "Skizzenbuch 11 x 17 - M" into dropbox.

Maciek, I added the web site as per your request, Please let me know if it is OK?

Simon, I replaced the images I had with the new Hi-Res images you sent me = Thank you!

If anybody sees and documentation errors or errors of any kind, then please let me know so that I may correct them...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Aug , 2015, 23:50
Simon.
Good to have you back. The valve (e) is the coolingwater connection valve to the aft torpedo room. The elements there like E motors, compressors, thrustbearings and sterntubes have their own systems including pumps and back ups, thus this e valve is very seldom used. As I don't`t think this valve needs to be frequently operated,  I guess it would suffice to have access by a simple floorhatch or plate, possibly only floorplate.
I guess somehow your system drawing placed the (e) at the discharge pipe from stb main engine cooling waterpump and not to the connection pipe to the aft torpedoroom.The latter connection is a central pipe going directly aft. Kindly note the coolingwater digram plate 13 has a mistake, the suction connection to the stb enginedriven cooling waterpump as well as the electric driven reserve coolingwater pump are hooked up to the main coolingwater crossover line, on plate 13 it is marked as no connection.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Aug , 2015, 23:36
Don
Your latest Skizzenbuch. In your prologue, middle dawing diving sequence page VIII, you still have a wrong wording on the venting of MBT3.
.........there is a ventvalve lever on both sides of the control room to blow the ballast for MBT3...... As you know and mentioned before you don`t blow the ballast by these venting levers. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Aug , 2015, 14:14
Hello Mr. Tore, Maciek, Simon, and Mark,

Mr. Tore - I corrected the dumb mistake in the prologue, thanks for keeping me correct!

Maciek - I added the info you provides about the Fwd Torpedo Room Gyro Angle Receiver and thanks for the info.

Mark - Thanks for the info on the German text, I updated Skizzenbuch with what you provided and I went through the rest of the indexes.  I corrected the miss spelled that I could find (there were several) and checked them with a web German translator to verify my changes.  It would be probably best to use the latest version of Skizzenbuch in dropbox.

I updated Skizzenbuch 11 x 17 - M with the latest changes, and I have about 50 pages to verify the text for Grammar and spelling...

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Sep , 2015, 01:22
Hello Mr. Tore, Maciek, Simon, and Mark,


I have finished my grammar and text review and placed the latest version of "Skizzenbuch 11 x 17 - M" in dropbox.


If no issues are raised, then I will most likely print this version to take with me to Schiffer Publishing next week.  Wish me luck...


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Sep , 2015, 21:40
Hello Mr. Tore, Maciek, Simon, and Mark,


I have uploaded the latest version of "Skizzenbuch 11 x 17 - M" into dropbox.  This version has all the German text corrections.


Mark has done a fantastic job in helping me with the spelling and symbols in the German text in the indexes.  For over a week, Mark has worked with me on a time intensive job.  I have worked on an average about 16 hours per day, and one all-night-er, and I know Mark has done the same.  I can't thank Mark enough for his tireless effort.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 Sep , 2015, 08:36
Hi Tore,

some time ago we had a short discussion on the naval uniforms. I have a request to you: could you please identify the uniform visible on the attached photo?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Sep , 2015, 10:54
Maciek.
I am not at all very  conversant with the different naval uniforms so this is just guesswork. I guess it is a German oberleutenant zur zee looking at the cap. after WW2. If it is an east German naval uniform it must be later than 1990 as the shoulderboards are removed. As you cannot see how many buttons the are on the jacket it is hard to tell whether there is a Bundesmarine or a late east German uniform, the early east German jacket had 10 buttons whereas the Bundesmarine I guess had 8 as the later east German naval uniform. I am sure there are other people having a better founded opinion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 28 Sep , 2015, 02:16
Hi Tore,

thank you for your answer.

Best regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Sep , 2015, 23:26
Hello Mr. Tore, Maciek, Simon, and Mark,

I thought I should post an update...  My wife Maureen and I drove the 750 miles to Schiffer Publishing in Atglen PA.  It rained all the way there, but we stopped over half way there in Roanoke VA.  We met with Pete Schiffer and my managing editor Bob Bionde and their staff; they were all very friendly and are great group of people to work with in publishing Skizzenbuch.

I attended several seminars covering all aspects of creating, publishing, and advertising a book. The facility is really a huge warehouse which stores many thousands of books. Previously I printed Skizzenbuck at the Office Depot and placed it into my metal leather covered post binder.  Office Depot printed Skizzenbuck on 11` x 17, 9.5 mil, 80 pound card stock.  The book is about 2 1/2 inches thich and probably weighs 20 pounds...  Heavy Reading!!!

Bob liked the way Skizzenbuch was set-up graphically and asked that that I send the Post Binder for the graphics entry staff as a guide when entering my coding into the system.

MY CODING... I had to read a Publishing Building Guide and create a text file and a folder for all the graphic files.  The coding involved defining all the various font sizes and then listing a command any time the font changes, and a command to insert a graphic file, location, and size.  Coding is much more difficult than asking Mr. Tore, or Maciek how things work on a U-Boat.  I'm at page 100 in my coding so far...

I believe Skizzenbuch will be very close to the 11 x 17 format and it will be in a book slip cover. I still need to talk with Bob anout the 7 large sheets that I have in a wallet folder in the back section of my post binder.  Well, that's it so far....

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2015, 00:36
Don.
Thanks for the update. I am impressed by the effort you are putting into your project. Wishing you all the luck and looking forward to receiving your further update.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Oct , 2015, 14:20
Hello Mr. Tore, Maciek, Simon, and Mark,


I have uploaded the latest version fo Skizzenbuch into dropbox.  A few photos were changed and re-arranged in the U-Boat Pressure Hull Construction segment throughout the book; nothing major.


Mr. Tore, are you still at your vacation home in the country, or back in the city?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2015, 14:25
Don.
I am back to the urban life and shall study the new latest Skizzenbuch tomorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Oct , 2015, 19:11
Hello Mr. Tore,


Welcome back...  Just to be certain; page 39 - the green vent lines between Regulating and RFO tank 1 and Regulating tank 2 each have a muffler in the plate 7 drawing.  However, we stare there is only 1 muffler...  Is that statement correct? I just want to make sure.


Could it have been different for U-570 Vs U-995 or U926?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Oct , 2015, 00:37
Don.
This is a typical example how the systemsketch deviates from the real thing. The sketch shows the principle, whereas the the real execution is the practical spacesaving reality. Indeed it is only one muffler for the combined port and stb systems. As the muffler only relieve the air it has ample capacity. I guess the system is applied on all VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2015, 23:04
Hello Mr. Tore,


I believe I had text issues on page 40, so I cleaned it up to make it more accurate (I hope)! I uploaded the corrected version of Skizzenbuch to drop box for your approval.  It amazing to still find issues with the text after reading it over so many times.  I guess my mind just fills in the correction as I read the book and I miss correcting the text errors!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Oct , 2015, 00:13
Hello Mr. Tore,


The locking pins for MBT 2, MBT 3, and MBT 4 vent levers in the control room were only installed when at Port... correct?  I can't imagine they would want the pins installed when on a war patrol... They could be in an emergency crash dive situation and the locking pins removal would be an unnecessary delay.


Do you remember if the locking pins were ever used on Kaura (U-995) or Kya (U-926)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2015, 00:28
Don.
I checked your latest correction on the common mufflers OK. I have a feeling that proofreading of your Skizzenbuch is a never ending task. On page 260 you still let the naughty female raise and lower your periscope ;D . Wench on the sketch two places. On page 370 you have an image of a ship with broken back, you name the ship a tanker, it looks more like a drycargo vessel look at the cargobooms and hatches.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2015, 01:18
Don.
When a submarine leaves the harbour the CO issue an order as to the state of seaworthiness of the vessel depending upon the mission, weather etc. This order usually includes if Kingstons should be open, Q filled or vent locking pins and stanchions removed etc. the order is normally put down in the CO.s orderbook and NO1 is responsible for the execution (R Nor.N). In peace time usually the locking pins are in and only removed when the order "prepare for diving" is given. On war patrol you would always be prepared for diving hence the lockingpins are removed. In peace time we normally kept the locking pins in they were only removed at the order "prepare for diving. Note these handles were easy to grab accidentally in heavy swell for support, thus a an extra safety could be necessary. We used them all the time in peace time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Oct , 2015, 19:55
Hello Mr. Tore,


When MBT 2 and MBT 4 are in the RFO configuration, the external gate valves are shut leading to the common vent duct. 


Question - do they shut the emergency vent valves  on MBT 2 and MBT 4 also, or do they not matter since the gate valve is shut?


When MBT 2 and MBT 4 are in the RFO configuration, I believe the blowing valves for MBT 2 and MBT 4 are shut on the HP air distributor.  That would allow the crewman to use the master blowing valve on the distributor to provide HP air to the other ballast tanks MBT 1, MBT 3, and MBT 5.  Correct?


Did they ever somehow lock or disable the valves for MBT 2 and MBT 4 while in the FRO configuration on the blowing distributor; like remove the valve hand-wheel?


When MBT 2 and MBT 4 are in the water ballast configuration, then all the valves are open on the HP air distributor and the master valve provides HP air to all the ballast tanks.  Correct?


Is there a reason to selectively blow ballast tanks?


Regards,
Don_


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2015, 01:59
Don.
I would shut the emergency vent valves in order to prevent fuel being forced into the venting duct.
I guess you are right in your assumption that the HP air distributing valves are shut to the MBT 2 and 4 as you normally only blow MBT 1, 3, and 5 in that configuration.
I don`t think we took any further actions except shutting the air distribution valves. The control room engineer was a responsible PO and usually the only person operating the blowingpanel and was knowing what he was doing.
I guess the individual distribution valves were provided for being able to compensate for major trimdeviations fi.waterintrusion. The volume of the air admitted to the tanks is depending upon the resistance (counterpressure, the variable depths) of the tanks and some MBTs are emptied faster ( using more air) than others thus it it convenient to compensate this by having selective blowing of the tanks and you get a very flexible system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2015, 13:40
Don.
On blowing the MBTs by exhaust you are even more susceptible to the resistance in the ballasttanks as you are blowing with much lower pressure than HP air. In extreme situations MBT 2 and 4 might take all the exhaust leaving it impossible to blow the other tanks as the exhaustgas escape via the saddletank Kingstons unless you are able to carry out selective blowing.
Tore.
   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2015, 22:15
Hello Mr. Tore,


I corrected all the issues that you pointed out.  Previously, I did a word search but that will not find text in a graphic.  Thanks for finding those errors...  I uploaded a corrected version of Skizzenbuch to dropbox.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Oct , 2015, 02:57
Don.
Checked your corrections OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Oct , 2015, 22:38
Hello Mr. Tore,


While reviewing the latter part of Skizzenbuch, I find that there are several instanced where the starting lever is called a Starting handle and vise-versa.  However, I believe both identifiers are correct...


If I place the following comment in Skizzenbuck, then do you agree that this will eliminate any confusion?


"Note:  (ANLASSHEBEL = Starting Lever) - The lever has an attached grip/handle (ANLASSGRIFF = Starting Handle) and the handle must be squeezed in order to change the lever position; both are considered to be the same integral component. This same logic applies to all the levers on the diesel engine operating panel."


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2015, 00:47
Don.
Yes, the handle is the last component of a linkagesystem consisting of levers and rods. You "grab" ( almost the same word in German "griff") the handle to move the linkagesystem.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Oct , 2015, 21:32
Hello Mr. Tore,


I uploaded what I believe will be the last version of Skizzenbuch into Dropbox...  I added a 6 page walk through of U-995  to the prologue to provide the reader with a physical reference point...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Nov , 2015, 01:08
Don.
Your 6 pages tour of the U-995 is a good idea. What do you mean by NCO room?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Nov , 2015, 15:26
Hello Mr Tore,


NCO = Non Commissioned Officer
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2015, 00:06
Don.
Shortcut on my side. The reason is that we normally used the name Petty Officers mess (PO mess) for this compartment and CPO mess (Chief Petty Officers mess) for the compartment between the wardroom and forward torpedo room. Your nomination should be OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: David83 on 06 Nov , 2015, 03:17
Great new Book .

Hi Guys i want to point in here there is a great new book on the market about the Persicopes on german submarines at Company Carl Zeiss .
There is everything inside how it works ,technikal specs ,Drawings how the mechanic to rise and lowering the periscope works ,assembly of it ,factory pictures and many more .
you can get it via amazon or ebay .

maybe a good addition for the technical guys here

wbr David
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 06 Nov , 2015, 12:51
Great catch David, thank you for sharing it!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 11 Nov , 2015, 22:11
Hi Tore,

I have a question concerning the two spare torpedo containers of the typseven/41 stored under the wooden deck (bow and stern) and the layout of the planked or slotted deck.

Please take a look at the attached picture: I have read that the late VIIC/41 had no spare torpedoes because of the continuous Royal Air Force threat it was a dangerous thus needless purpose. So when the spare containers (blue layers on the drawing) were removed, I suppose that the layout of the wooden deck was also fitted and the cutouts (red layers) vanished too?

The reason behind this questions is that the (well known) underlying drawings from Koehl/Niestle ("Vom Original zum Modell) are showing a late VIIC/41 with slotted deck and spare torpedo containers. The refueling bow is IMO a indication that this is a "late" VIIC/41, so the deck should be planked and the spare torpedoes removed. It is no reflection on Koehl and Niestle work – I suppose they drew a general plan and had to consider a wide range of different u boat modifications – it is just for my understanding.


Thanks in advance
falo


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Nov , 2015, 01:09
Hi Falo.
U-995 was launched July 1943 and not fitted with torpedo containers in the casing but with wooden planking deck. The GA drawing from Koehl/Niestle is dated 1948 and shows a slotted deck, no torpedocontainers and four storage containers having hatches on deck. The containers as well as the wooden planking hatches were easy to remove and install. Below are some photos I took back in 1953 of the U 995 were you can see the wooden deckplanking. As far as I can see there are no wooden hatches for the torpedo containers, it might be two hatches used for storage of mooring equipment and a rubber dinghy as far as I can remember. I guess the wooden deck and hatches varied particularly towards the end of the war. In spite of the GA drawing of Koehl/Nietsle, the U-995 during the war did not have any storage containers in the casing, 2 containers were later installed by the Norwegian navy. Other Norwegian VII Cs had three and four containers.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 12 Nov , 2015, 13:47
Hi Tore,


thank you very much for the information.


Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2015, 16:17
Hello Mr. Tore,


I made some changes in the U-Boat dive angle drawings.  The location of the aft hydroplane should be located very close to the rudders.  Do you approve of my changes?


Regards,
Don_


Original...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2015, 16:18
Changes...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2015, 16:20
Changes....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2015, 16:22
Changes...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 21 Nov , 2015, 16:48
WOW didn't realize the diving angle was that steep.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2015, 22:29
Battery design...


The air entrance opening is designed in such a way that during a boat’s inclination up to 35° in any direction no acid is spilled from the cell.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2015, 01:46
Don.
Diving angle and depth difference.
I am afraid you have misunderstood my sketches of illustrating the relation between diving angles and pressure differences (depths). On my first sketch (below) my idea was to show the Kingstons in MBT 3 marked green as an indication that the green marks are the free flood gates of the MBTs, meaning the points where the seawaterpressure set the differential hullpressure in relation depthdifference caused by the diving angle. So the green markings fwd. and aft are only markings of the freeflood areas of MBT1 and 5. as you know there are no Kingstons on these inlets. At even keel you would notice there is a higher pressure in MBT 3 than MBT 1 and 5. A practical consequence of this is that it would require more air per M3 tank volume to empty MBT 3 than MBT1 and MBT 5 at even keel. Under normal circumstances this would have impact when blowing the tanks by exhaust gases. You start to blow the saddletanks having the Kingstons at the highest position ( lowest counterpressure), continue blowing MBT1 and 5 having the next lowest counter pressure until you are that high up that your MBT3 gets an acceptable low counterpressure for the exhaust. Thus it is no attempt to indicate the position of the hydroplanes by green markings as they are irrelevant in this case. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2015, 03:16
WOW didn't realize the diving angle was that steep.
This is a crash dive angle which normally is not common. It requires some skill as you have to watch, what in the Royal Navy submarineservice is called the Duchess Ass, which is the ultimate aft end. If this part is too high above the surface you have a problem with the thrust of the propellers. The ideal angle is when the wind deflector on the bridge and the Duchess Ass is descending the seasurface simultaneously.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Nov , 2015, 18:45
Hello Mr. Tore,


The labeling on the first drawing "Free Flood Gates" resolved the issue for me! I think it was needed to help the reader as well...


I uploaded the latest print version of "Skizzenbuch 11 x 17 - M" into dropbox...


Thanks you!
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2015, 00:41
Don
Your last Skizzenbuch uploading is correct.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Nov , 2015, 21:33
Hello Mr. Tore,


I have completely gone through Skizzenbuch for hopefully a last time looking for any words that should not be used when describing anything within a U-Boat.  Those words which you have impressed upon my newly learned vocabulary such as closed/shut, dive tanks/ballast tanks, ventilation valve/vent valve (2 very different systems), flood valve/Kingston, dive plane/ hydroplane, and of course wench/winch.  (Wench) Obviously we don't want women with loose morals on a U-Boat; except in a crewman's romantic dreams.


The only thing I don't have yet is the foreword written by Jak P. Mallmann Showell. I believe he wants to wait until the publisher produced an approved version of the book. He liked the book's general idea and format, but took issues with the German text, and perhaps my writing skills.  I got help from Mark Hessburg with the German text, and I have attempted to improve my writing skills.


I have uploaded the version of Skizzenbuch 11 x 17 - M that I will send to Schiffer Publishing along with my Leather bound metal post binder to be used as a general layout guide for the publishing entry personnel.


Again, thank you for all your help with Skizzenbuch...
Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Nov , 2015, 21:47
I have attempted to improve my writing skills...


Hi Don,

I know that you mean :D

I have spend the last fours weeks writing, rewriting and some more rewriting my thesis for my Master's.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Nov , 2015, 00:00
Don.
I guess a book like yours is never finished, but I admire your stamina and courage to go through the whole process. Looking forward to seeing the complete book. Same goes for Simon, you two have contributed a lot to improve the understanding of the VIICs constructions and operation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2015, 22:43
Hello Mr. Tore,

The regulation tank configured for the deep diving configuration discharges about 100 liters/10 meters when diving using the main drainage pump in the 2 stage configuration.  The initial air pressure in that tank was set to 10 to 12 Kg/cm2, and the tank design is for a maximum of 14 Kg/cm2. While diving, the tank's internal air pressure will be reduced, but this is of no consequence. The opposite actions take place when the U-Boat ascends to periscope depth and the water is pumped into of the tank and the internal air pressure increases to the previous state.

If the dive was to escape an enemy depth charge attack, then I would head off in a desired direction to assure I escaped the surface vessels.  Every once in awhile I would stop and listen to assure I'm not being followed. Then at some point, I would initiate a surfacing procedure. My reason for this thinking is that I don't want surface vessels waiting for me to bring the U-Boat up to a ramming depth or a shallow depth charge depth. If the U-Boat were coming up to the surface and the enemy was setting quietly waiting, then they could possible listen and hear the pumps taking water into the deep diving regulation tanks. Does my thinking make sense?

The regulation tank configured for the shallow diving configuration may take in water by allowing the tank to vent internally into the pressure hull, or remove water from the tank by increasing the tank's internal air pressure.  I believe these maneuvers are done while running at periscope depth; they don't want to run the pumps and create noise.

When the U-Boat tanks are in the Reserve Fuel Oil configuration only one regulation tank is available, a Port and Stb saddle tank.  I thought they could use one side for the deep diving configuration, and one side for the shallow diving compensation.  Is that correct?  Was there any preference as to which (port of stb) tank was assigned to the deep diving configuration?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2015, 00:50
Don.
Tne way of operating a VIIC during various attacks and counterattacks varies depending on the time and the technical development both with regard to the air superiority,Sonar and Asdic. On the net San Fransisco Maritime National Park Association you shall find the submarine commanders handbook ( U.Kdt.Hdb.)for a VIIC issued in 1942 in force as from 1943. You shall find the German Navys recommendation to the CO for maneuvering under various circumstances, including escape of a depthcharge attack.
I guess at that time the advice was to change depth dynamically by speed and hydroplanes not by using regulating tanks pumping or flooding and use the diminishing displacement without regulating to speed up matter. When required depth is obtained I guess you eventually had to compensate by careful pumping/blowing the regulating tanks depending upon the CO`s judgement.
When you are surfacing, you would use dynamic forces and not pump in regulating water, you rather use flooding without using the pump and venting the tanks inside the submarine. I guess I would use both tanks simultaneously preventing atworth list.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Dec , 2015, 00:48
Hello Mr. Tore,


Is atworth list a roll or tilting effect? I google atwort list and I only find a location for Atworth in the UK...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Dec , 2015, 02:31
Don.
I am afraid it`s a bad spelling for athwart, used for a list either to port or starboard .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Dec , 2015, 13:23
Hello Mr. Tore,


Thank you for the info...  No problem with the bad spelling.  That's a problem that I have been dealing with for decades along with my dyslexia.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2015, 23:39
oo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: OldNoob on 23 Dec , 2015, 00:06
Nice artwork tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Dec , 2015, 10:08
Hello Mr. Tore,


Merry Christmas and Happy New Year to all...  The best thing about the New Year is Old Friends!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Dec , 2015, 10:14
Hello Mr. Tore,


Is that a new paint program?  The frame in your Christmas Card image is in a 3D format; Great job!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Dec , 2015, 23:02
Don.
No it`s the same old programme, I just downloaded the frame from the net. Wish you all the best for the year to come hoping your Schizzenbuch would materialize.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 Jan , 2016, 03:07
Hi Tore,

I have got question about trim pump. I know, that it is electrically driven, two-cylinder, double acting piston pump with vertical worm shaft.
However, I'm not able to locate the pump cylinders.
Here:
(http://oi64.tinypic.com/15yer0x.jpg)

I have uploaded two views of the pump. What are the two "bulbs" at the front? Are the cylinders located behind?

--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jan , 2016, 06:25
Maciek.
Good to have you back. The trim pump is as you say a double cylinder piston pump, I don`t recall it as a double acting though. The casings for the piston cylinders are difficult to see down behind, but what you see in the front of the pump are the two "bulbs" which are only two buffers (called airvessels) having an aircushion on the top to equalise the reciprocating pump pressure fluctuation in the water both to  avoid pulses and noise in the pipeline. The two smaller "bulbs" are the Valvechambers for the suction/ discharge valve chambers. Unfortunately I don`t have a cross section drawing, but may be a cross section of the double cylinder coolingwater pump for the main engine will do for an explanation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Jan , 2016, 03:48
Hi Tore,

good to hearing from you.
Thank you for the answer.

On the drawing below I have tried to mark the components of the pump - in my
opinion at least.

(http://oi64.tinypic.com/95o7pz.jpg)

Does it make sense?

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jan , 2016, 06:36
Maciek.
I believe you have got the idea, anyhow for a singleacting pump, for a double acting pump it is a bit more complicated as you got to have crosshead to be able to utilize the underside  of the piston which would imply a somewhat higher pump. It could be there is a mix up with a double pistonpump and a double acting pump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 09 Mar , 2016, 08:19
Hi Gentlemen,

I hope you are doing well.

Here is the link the to the page, where is described story of the U534 conning tower replica:
http://www.modelartanddesign.com/page23.htm

Though U534 was type IXC U-Boat, I let myself to post this link in this sub-forum (:) ),
because one of the photos presents interesting technical detail: interior of the diving planes
(or main rudder) console:
(http://www.modelartanddesign.com/USERIMAGES/Helm%20as%20arrived.JPG)


And the photo of the renovated console:
(http://www.modelartanddesign.com/USERIMAGES/Helm%20complete.JPG)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2016, 10:14
Hi Maciek.
Doing fine thank you! Just renewed my driving licence which is not an easy job in this country when you are 87. In fact to day I feel I could go down to Kiel and crank up good old U-995 any time if she would float.
The tower of U-534 seems to have been excellently restored I am sure for a considerable price and the rudder/hydroplane console is a beauty  however i don`t believe we had a two colour version, I guess the whole thing was dull grey. Even the handles and knobs were not shiny.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 11 Mar , 2016, 08:49
Maciek, many thanks for the link: plenty of great shots. The console new look is outstanding too. And yes, doing pretty fine
Cheers
SG
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 17 Mar , 2016, 14:56
"In fact to day I feel I could go down to Kiel and crank up good old U-995 any time if she would float."


Hi Tore,
it seems that your old maid "Kaura" (Ex U-995) will be dressed up for your proposal: Please look at attached pictures, visited Laboe yesterday and have taken same photos. The deck section around the snorkel cutouts is covered by a tent. I suppose the upper pressure hull underneath the cutout is rusty and has to be renovate.You can recognize a compressor on pic "0014". IMO a sure sign that this section is provided for a accelerated drying.


Regards
falo


P.S: If you need a mate for cranking up U-995, it would be a honour for me to enlist as a volunteer under your command, Sir!   
;)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Mar , 2016, 15:42
Falo.
Thank you for sharing recent images of my old lady. I guess she needs some Botox to cover her wrinkles and scars. For all you guys who fancy canning, the light on falos photos reveals the susceptible platings for the saddleballast tanks 2 and 4. You clearly see the dents in those areas whereas in the pressure proof area of the Q, regulatingtanks 1 and 2 you hardly see any dents. Canning and denting is not only to start carving the hull and saddle, it needs knowledge where to put it as well. Excellent photos Falo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 18 Mar , 2016, 14:18
Hi Tore,

yes you are right your old lady needs a little make up, because she is a bit rusty (see attached pics "0009", "0013", "0026" and "0029".

I suppose preservation is very difficult because U-995 is not an indoor presentation like U-505 in Chicago. So the ravages of time won't reprieve the boat.

I haven taken two pictures in addition which assist your thinkings about model scale, rivets, carving, canning and denting. If you have look at picture "0006" (stern) you can recognize how small the rivets are. Picture number "0022" is a very rare one from the flood holes at eye level. You can see clearly the frames of the inner structure through the flood holes. The drip channels at the lower left side are not accurate because they just for draining the rain and dampness (as you've mentioned before).

Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2016, 01:35
Falo.
Interesting details of the present condition of U 995. Indeed an illustration of the small almost invincible rivets on the casing. The real steelrivets occur only in those area where you need strength like the riveted hatch for fitting the main engines into the pressurehull. I guess the majority of the corrosion damages of the pressurehull was done while she was laid up afloat almost five years prior to the Restoration. As you might see from the image below she was in bad shape at that time, having practically no antifouling and corrosionprotection. The casing was very susceptible to corrosion even in my time and as I have told before almost half the fwd starboard casing was swept away in a gale crossing the Northsea to Scotland in November 1953.
I still maintain my point of view, it is a pity that modelbuilders overdue the canning, rivets and the pressurehull corrosion inspired by the museum U 995 as an operational Uboat would never have such damages.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Mar , 2016, 23:12
Hello Mr. Tore, Maciek, and All,


Maciek, I really like the photos of the BBC unit; a great find...


Skizzenbuch, seems to be going along OK with the publisher.  I have not had any return emails or notices for issues with my original text file, or the printed Metal Leather Covered Post Binder Book (11 x 17).


During the past 30 days, I have gone through eye operations for cataracts in both eyes.  I didn't realize my eyesight was that bad.  However, while writing Skizzenbuch, it became more difficult to focus on my computer screen.  When I first went to the eye doctor, they attempted to measure the thickness of the cataracts running down the center of both eyes with a light reflecting instrument.  However, on one eye they had to use a device with water and sound (i.e., ASDIC/SONAR) to measure the thickness; it was that bad.


After the first eye lens replacement, it was amazing - I could see clearly and the colors, they were so bright and vivid.  I could cover the now good eye and the other normal eye still had the wide cataract streak down the middle, but the other areas of sight was like looking through a glass of iced tea.  I didn't realize my eyesight was so deteriorated over the years.  Three weeks later, the other eye lens was replaced in the Laser Assisted cataract surgery.  I was far sighted so I had the astigmatism corrective lenses installed which cost me $3330.00 total and worth every penny.


I will keep everybody updated on the Schiffer Publishing progress with Skizzenbuch...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2016, 01:26
Hi Don
Sorry to hear you had eyetroubles. I have been through the same thing and experienced no further troubles afterwards. I have been using the skizzenbook a few times and I miss an easy way to find what I am looking for. Would it be an idea to have a register?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2016, 17:22
Hello Mr. Tore,


I thought about an INDEX in the back of the book, but never got around to it.  The CONTENTS on pages 4 and 5 generally get you into the ball park.  If I need to search for something, I generally use the PDF edit tab and then use FIND to locate a specific word... Although, this is not an option for the printed book.


I just looked at the Skizzenbuch PDF with my new implanted lenses and it is really bright and colorful; I didn't notice that aspect before...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2016, 23:58
Hello Mr. Tore,


I found a piece of free software which allowed me to build an index from Skizzenbuch... The file name is Skizzenbuch Index.pdf and I uploaded it to dropbox at the Skizzenbuch folder.  Please let me know what you think and feel free to make any suggestions.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2016, 01:52
Don.
I just downloaded your index software and it seems to me it is exactly what I am looking for. Let me test it for a few days and I`ll give my comments if any. May you have a colourful Easter with your new lenses.
Regards
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Mar , 2016, 10:24
Hello Mr. Tore,


Glad to be of assistance...  You certainly have an eye for the outstanding Easter image with the chocolate eggs and Kaura S309 in the magnifying glass...


Happy Easter to you and All,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Mar , 2016, 00:50
Don.
I have tested your index system a few times and have a few remarks. The idea is very good and very handy for f.inst. modelbuilders who can look up whatever item they require to get detailed information. However somehow the system does not pick up several important items as tanks , regulating tanks , ballasttanks, Q tank, negative buoyancytanks etc.  Further fuel,trim,tower,vent, exhaust, pressurehull, rudder and several other important items are not picked up. The idea of an index would definitely be an asset if it is possible to improve same.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Mar , 2016, 18:42
Hello Mr. Tore,


I created a new index file and uploaded it to dropbox... I have some limitation parameters when I search for words to index; no double words, and I set the word length to 3 letters or  more.  Q Tank may be found by just searching for tank.  However, I added most of the words you suggested.  What do you think of the latest index?


Skizzenbucvh 11 x 17 M1.Index


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Mar , 2016, 00:42
Don.
It is indeed better, however I guess somehow you have to get around the problem with double words as you get in excess of 100 pages containing, hull, tank, tanks etc. I have no idea how to overcome that problem, but I bet with your expertise you`ll find a way. I still think it is worth while, there are many out there looking for such a manual.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Mar , 2016, 19:16
Hello Mr. Tore,


I spent more time with the index generator and I have created a much better index with linked words.  The only thing I can't get around is the "Q Tank"...  I would need to use a 1 letter search and every word in the book would appear as a index optional entry.  However, I did get Negative Buoyancy Tank as an entry...


The latest file uploaded is INDEX.pdf...  How does this one look?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2016, 00:54
Don.
Again an improvement, however f.inst. if you are looking at the word bow you get almost 50 pages with the word bow, of which more than 2/3 are containing   "unimportant" words like bow vents, bow tanks  etc not really the bow itself. I guess more than 10-15 pages containing the relevant word makes it a bit cumbersome to use,  it would be an advantage to get rid of this problem f. inst. by making a search instruction like if you want an info on the bow design like Atlantic bow, bow flare, bow hawser etc you use linked words to limit the pages. I guess by checking all the words giving a search result of more than 10-15 pages it might be possible to find a system to overcome this problem. It exists probably a solution made by others somewhere out there as it ought to be a common problem I guess.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Mar , 2016, 12:56
Hello Mr. Tore,


It looks like I can get around most of the issues you have brought up by refining the word list to multiple words instead of one word.  I have incorporated many of your suggestions in the latest uploaded INDEX.pdf to dropbox.  I even did a separate index project with 1 letter and created a two word index for Q Tank/Q Tanks, then I copied it into the final Word/PDF files...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2016, 23:47
Don.
Much better and very usable. Somehow a few items like Papenberg, IMO, Roots (blower), galley,MAN, Krupp Germaniawerft are missing whereaes you got f. inst. Telefunken. It could be many more of course, may be you are able to fix this and you`ll have an approved handy system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Mar , 2016, 18:31
Hello Mr. Tore,


I spent several hours going through the index and eliminated most of the long page entries with further word extensions.  However, I did leave a few of the long page entries because this was pertinent data.  I believe the latest INDEX.pdf in dropbox looks fairly usable with all your help.  Thank you sir for your expert assistance...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2016, 00:07
Don.
I guess you got the index solution. The Skizzenbook has become an unique hand book for everybody who wants to dive into details of the VIIC`s. Most of the questions raised over several years in my mailbox would be answered by your book I look forward to seeing the final printed result.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Mar , 2016, 16:00
Hello Mr. Tore,


I went through Skizzenbuch and refined the index to the point that I believe this will be the final version which I uploaded to dropbox.  I also look forward to seeing the Schiffer Publishing version of Skizzenbuch. 


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2016, 08:04
I sometime get questions on the emergency escapes from U boats.
In general I can can only say the survival statistic is not very impressive and I only know about a handful successful attempts of the German boats. In the last accident in the RN I remember in my time the RN T class submarine HMS Truculent which collided with the Swedish tanker M/S Devina at the entrance of the Thames January 1950. There was quite a number of people on board as she had some yardpeople in addition to the normal crew. I guess some 57 people managed to surface but were taken by the strong tidal current and perished in the cold water some 20 were picked up. The escape is one thing, but survival on the surface depends on what kind of support is available. The WW2 standard of escape equipment was by no means comparable to to days standard.
In general the VIIC`s pressure hull is divided into 4 separate pressureproof compartments, the control room separated by pressureproof bulkhead from aft and fwd compartments and conningtower separated by the  pressurehull including by lower tower hatch. In addition you have the aft torpedo- and E- room, main engine room, the compartment consisting of galley and PO messroom, the compartment consisting of the sonar,radio, wardroom and CPO mess, and forward torpedoroom separated by watertight bulkheads. The watertight bulkheads have doors a bit low from the upper part of the pressurehull and the pressure hullhatches are equipped with a coaming.
In the event of an emergency escape, the lower doors and coamings all keeps the residue air in the compartments stable when flooding. The whole boat has to be flooded and the pressure tight compartment shut. You have now three separate escapehatches of which all if possible should be used as you have limited escape time, both with regards to pressure (bends) and chlorine gas emission from the flooded batterycompartments. When the uboat is flooded you pull down the escape hatch coamings lengthenings trunks which now ends submerged in the floodwater as the pressure equalizes with the ambient seawater pressure, at the same time the watertight bulkheads keep the trapped pressurized compartmentair up towards the pressurehull.
The crew is ordered to put on the Draeger breathing- and escape vest. This equipment is used both as and breathing apparatus or as an ascend/lifevest having an oxygen canister and a hydrosodium cartridge for CO2 absorption. In case of excessive chlorine gases the vest is used as a breathing apparatus otherwise the crew is waiting above the waterlevel breathing the trapped compressed compartmentair. A man dives under the hatchcoaming up to the escapehatch which now can be open as the pressure inside the u boat is the same as the ambient seawaterpressure. He has to be aware of the danger as the trapped air in the duct escapes as the hatch might slam shut when the airbubble collected at the top escapes. Now the waiting crew can take a deep breath of the compressed compartment air, dive under the coaming and have a continuous column of water up to the surface. While ascending the crew has to exhale all the time to let the compressed air out otherwise you might experienced a lungburst. Usually you are told to start whistling when escaping and due to the risk of "bend" you should adjust the ascendspeed ( by adjusting the air in the Draeger vest) to that of a small following airbubble. Normally a successful escape depends on the support you get on the surface almost everybody needs a decompression chamber treatment. The effect of having a human body exposed to high airpressure might be compared to a sodapop bottle, as long as it is kept under pressure it stays calm, but when you open the cork it start bubbling. The same happens to the human blood and can cause a fatal embolism hence you have to release the ambient airpressure slow ( in a pressurecamber).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Mar , 2016, 19:45
Hello Mr. Tore,


Excellent information; thank you for sharing your years of knowledge and experiences, and please continue to do so...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Mar , 2016, 00:39
Escape equipment.
Further to my yesterdays post I may enlighten you a bit on the escape hatch details and coaming. The main escapehatch would be the upper conningtower hatch and the lower conning towerhatch having a permanent coaming ending in an expandable lengthening which could be pulled down to some 1650 mm above the controlroom floorplates . I guess this expansion coaming was originally made of 3mm sheetplates, however in my time we used a canvas trunk normally stowed up toward the permanent coaming as can be seen on the image below. As can be seen on the image they have removed the expandable coaming on to days museums U-995 and put a grating over the hatch opening.
As previously stated when flooding the tower, air shall be compressed and trapped towards the conningtower top hatch. By opening the hatch this air shall escape causing a pressure fluctation which might slam the hatch shut. The  hatch is provided with a catch normally to protect it from being flung open by the normal overpressure in the boat, this catch now allows the hatch just to open a crack to release the air. In addition you have a small checking cock which could be used for venting the air, however it is too small for practical use.
The time you are exposed to high airpressure ( the trapped air) is crucial with regards to bend and you have to reduce same by make the flooding and waiting time for the escape as short as possible.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Apr , 2016, 01:27
A well known discrepancy between the real VIIC and the Revell building kit 1:72 is the position of the anchorbay, which Revell has placed app. 1,5 frames  aft of of the real design. As seen on the modell kit the anchor would hit the fwd. hydroplane when lowered. Accurate modelbuilders would have to replace the anchorbay approximately one frame ahaed of the centerline of the fwd.hydroplane guard.
On the museum U 995 they have done another modification by introducing, for some unknown reason, a stopper for the anchor fluke, see image. As so many other details on the museum U-995 this should not be introduced on an accurate model.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Apr , 2016, 03:36
As probably known, the Royal Norwegian Navy took over 4 ex German uboats after WW2. Three of these were VIICs. Early 1960 we had plans to modernize the VIICs and KNM KYA ex U-926 was partly converted. Below is an image of the submarine after getting a new sailtower. An interesting detail is that the old hinged schnorchelmast was kept in a new homing in the sailtower thus no telescopic schnorchel.

Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 03 Apr , 2016, 08:40
Thanks for the information about the correct position of the anchorbay, Tore (and about all the other untold-before details). You're a gold mine, Sir. I'd suggest to celebrate the 200th page in your thread, it's quite an achievement!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Apr , 2016, 02:38
I have been involved as a VIIC and IXC technical adviser for a Canadian fiction author writing a WW2 uboat novel on uboatoperations in the Artic. In this connection I have tried to advise the author about the sonar mirror layer which you experience in these waters.
Apart from the problems of operating a VIIC under the polar ice, you have the well known WW2 submarine trick of hiding under the sonar reflection layer. In my time we had problems with unidentified submarines operating in the deep Norwegian fjords, like the Swedes we never caught one. Our theory at that time was that somebody used the fjord for training submarine COs of hiding under the sonar reflection layers which was quite frequently existing in the fjords. When rivers from the mountain lakes ends up in the salty fjordseawater it creates a layer of different salinity, eg. gravity, which reflects the sonar beams and hence acts like a sonarmirror protecting the submarine. If you in addition are able to stay dead silent under such a layer you would be fairly safe as neither the active sonar nor the hydrophones would pick up anything. However it requires some skill to place the submarine in such position. When you have found the layer by taking temperatures and watersamples, you used the regulating tanks to adjust accurately the submarine to neutral buoyancy, shutting down almost everything, placing the boat under the reflection layer. By topping up the hydraulic system on beforehand you are able to silently adjust the minor variation in buoyancy by lowering and raising the periscopes by using the hydraulic accumulators thus silently adjusting the displacement and buoyancy. This required some training and we were in my time of the opinion our fjords were used for that purpose.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Apr , 2016, 00:16
Hello Mr. Tore and All,


While I was working on the INDEX FILE file I discovered 19 duplicate words with different spellings in the index generator file??? IN other words wrong spellings! I corrected the spelling errors and uploaded the latest Skizzenbuch 11 x 17 - M.PDF file into dropbox and the INDEX FINAL.PDF...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Apr , 2016, 03:00
Don.
Finally the site is back. My reply to you disappeared in the commotion. I had a quick glance at your last index and it seems OK to me.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Apr , 2016, 14:13
Hello Mr. Tore,


Do you remember about a year and a half ago when I had a wrong understanding about the Regelzellen external fuel oil saddle tank.  I believed the saddle tank was open at the bottom which allowed the fuel oil to be pumped in and float on top of the sea water in the tank; as the fuel oil was consumed/burned the water level would rise in the tank.  At that time, the only issue I had was what stopped the tank from being dumped in rough seas with an open bottom?


In the first chapter of "Type VII U-Boats" around page 16 this was stated as the self-compensating fuel Oil tank design open at the bottom to the sea.  Originally, I got that idea from a German U-Boat web site, so I don't know which started that design idea. It looks like that wrong idea was put forth because there was no experienced U-Boat EO to explain the actual Header Tank Water Compensating System and the Regelzellen tank design which was backed up with the actual Type VIIC U-Boat engineering drawings!


Experience definitely comes in handy...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2016, 01:12
Don.
I cannot specificly remember the discussion, but the system works as follows. The regulating and fueloilbunker tank 1 stb and port are as you are saying, external saddle tanks. They are not watercompensated as the normal fuel tanks and as the capacity is limited to  4.700 m3 each, the surface effect is small. As fueltanks they are filled like the other fueltanks but instead of forcing the compensatingwater out of the tanks you can either drain the residue water, if any, by the ballastpump or/and vent the tank through the mufflers in the controlroom. As you see from my image below the tanks are connected to the fuelsystem as any other fuelbunkertanks but as it is no compensatingwaterpressure to squeeze out the fuel, you transfer same by airpressure supplied by a LP air (0.5 bar) pipe to the tank, as an alternative you might even use the spare luboilpump in the engine room to transfer the fuel as can be seen on the image.
 It goes without saying that when the regulating tanks are switched back to regulatingtank configuration, the tanks are contaminated by fuel which might leave an oilslick when in use. That is the reason why the regulating tanks are able to discharge the regulatingwater into the MBT3 while submerged keeping it on top of the MBT waterlevel until surfacing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Apr , 2016, 16:20
Hello Mr. Tore,


I have some questions about the early Type VII U-Boat that had the stern torpedo tube mounted in the upper deck area  In that configuration:


1. Could they only launch the stern torpedo while submerged and not while surfaced?
2. While submerged did they use the piston to launch the stern torpedo as to not create air bubbles to give up the U-Boat's location?
3. Was the gyro angle set in the stern torpedo, or was only a straight shot configuration available?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Apr , 2016, 00:18
Don.
As you know I am not a torpedoman, in fact I stayed away from it as much as I could, I guess Maciek is the right guy for answering your question. In my time we never fired a real shot with the aft torpedotube. I cannot see anything which should prevent you from launching a torpedo both submerged and surfaced, and using a piston the same way as in the forward tubes. We occasionally tested the launching bubbles usually in surfaced condition using a dummytorpedo as can be seen from a photo I took back in 1953 outside the submarinepen in Trondheim. Not much of lauchingbubbles as far as I can see. The setting of the gyroangle I am afraid I have to leave to Maciek.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 30 Apr , 2016, 03:39
Hi Gentlemen,

Don, you have asked interesting questions regarding the aft/external torpedo tube on the first version of the type VII U-Boats, known later as type VIIA.

1. Could they only launch the stern torpedo while submerged and not while surfaced?
2. While submerged did they use the piston to launch the stern torpedo as to not create air bubbles to give up the U-Boat's location?
3. Was the gyro angle set in the stern torpedo, or was only a straight shot configuration available?

I have researched this topic some time ago and I think I have the answers to two of them.
Based on the Schussmeldung from torpedo attack conducted on 6th December 1939 by U31 (http://uboat.net:8080/boats/u31.htm) (on Estonian merchant Agu (http://uboat.net:8080/allies/merchants/ships/131.html)), I can say, that torpedo was fired from aft torpedo tube, on the periscope depth (13,5 m), with the gyro angle 61,5 deg.
Regarding the piston, I do not have any direct information, but I suppose, it was also used in case of external torpedo tubes.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Apr , 2016, 11:13
Mr. Tore and Maciek,


Thank you all for the info...  Due to the placement of the aft torpedo in the deck casing; I highly doubt the aft torpedo could be launched during a surface attack on the Type VII A.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 May , 2016, 01:04
Hi Don,

Due to the placement of the aft torpedo in the deck casing; I highly doubt the aft torpedo could be launched during a surface attack on the Type VII A.

I guess you are right. However, one should review available Schussmeldungen to tell for sure.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 May , 2016, 17:05
Hi Maciek,


OK...  By the way you will need to re-upload your image as a jpeg to get the image right.  I had to do that to get my image corrected...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2016, 12:02
From time to time discussions pops up on the two "blisters" which are seen on both sides of the VIICs bow approximately between frame 77-78 or about the same location as the capstan. I have seen many fantasic speculations particulary related to the torpedo launching system. The " blisters" can be seen on the VIIBs as well. I have studied the arrangement and can not say my conclusion is 100 correct, but I assume the "blisters are the venting/ flooding gates for the very narrow difficult freeflood space between the pressurehull and the casing in this area. The flood/venting gates have a streamelined cover having outlet towards aft which creates a ejector effect when sailing ahead which facilitates efficient draining.
On my image below I have tried to explain my idea. On several drawings I have seen MBT 5 is including this void space, however on the original drawings MBT 5 has a bulkhead shutting off the space between frame 80 and the weldingseam for the fwd dome of the pressure hull. This bulkhead goes from the top to the centerline for the lower torpedotubes and from there slopes down to the aft floodgates at frame 76. Hence the void space between the pressurehull and the casing is a freeflood area which has to be drained (and flooded). The area is marked blue on my images. I have not yet seen modelbuilders considering this detail on the Revell kit.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 May , 2016, 13:45
Hello Mr. Tore,


I like the new Avatar you have chosen for your online image...  I believe the Revell Type VII C U-Boat model does have the ejection ports you are describing.  At least according to the image I was able to pull from the internet (Ejection Port image), and  perhaps a bit too low.  My OTW 1/32 model had the ports in the fiberglass hull which called for them to be cut out (Ejection Port 2 image).  It took weeks to cut out all those holes in the fiberglass hull and seal them with epoxy glue so water would not wick up the fibers and ruin the finish...

Note the Revell model has an attachment between the fairing and the Fwd hydroplane, and the OTW model does not.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2016, 14:29
Don.
Yes for sure all the Revell kits have the blisters, may be a bit too small, what I ment is up till now I haven`t seen somebody drilled a hole for the outlet of the blister. I took the opertunity to make a new avatar while the site was down I am happy you liked it, it`s more a navystyle.Unfortunately quite a few images disapeared I talked to Wink about it but unfortunately he can`t recovered same but mentioned possibly to make a gallery if I could find back all the hundreds I made I am glad you downloaded what you needed for the Skizzenbook.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 May , 2016, 17:59
Hello Mr. Tore,


I still have all the images that I downloaded from the web site; plus many of the images with a series of changes until the final version in Skizzenbuch. In addition, I have 100's more form the net, Maciek, and you.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2016, 23:12
Don.
Good to hear I`ll revert if Wink consider to make a gallery.
Torel
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2016, 06:07
Don.
Got a message today, they are going to invest money to make a gallery within the site. I`ll guess we`ll get the info when same is ready. I think such a gallery would be of great interest and value to Uboat enthusiasts around the world. Allthough not yet fully aware how it would work I am looking forward to using it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: zhuravlik on 09 May , 2016, 09:10
Hallo zusammen,
i'm the idiot who photoshopped the Kya picture.
I'm converting Revell 05100 to KNM Kya and I needed that photo for reference and showing purpose.
Since I can't open those photos at page 169 and 170 of this thread( get error "bogus dqt index 10") would you please upload them again?


Thanks in advance,


Frank.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2016, 10:26
Frank.
The conversion of KNM Kya startet about 1959 I left her 1956. Our submarine designer had just finished his work converting our old british U class submarines which did not had a schnorchel, hence modernising the U class involved a major rebuild not only a sailtower but a telescopic schnorchelmast as well. Prior to our major newbuildingprogramme 15 submarines in Germany we looked into the possibility of modernizing our 3 VIICs. Our chief designer Kaare Hegstad used pretty much his experience with the rebuilding of what we called the Ula class eg. the British U (V) class but choose to keep the hinged original german schnorchel which got a homing into the sail. A few faked photoshopped Kyas exist but only one was actually rebuild showed on the photo below.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2016, 10:31
Frank.
A Photo of the KNM Kya in my time shows the old norwegian tower, three deckcontainers and she had of course three Kingstons on MBT 3 on both sides as all the VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: zhuravlik on 09 May , 2016, 10:44
Te Deum laudamus!
Thank you very much, Mr Tore!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2016, 11:21
For your interest, here is an image of one of our U class submarines with the new sailtower, including schnorchel. As you see it looks very much like the sailtower of KNM Kya, same designer.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: zhuravlik on 10 May , 2016, 09:39
Mr. Tore, you are great, really!

I don't know how to manifest my extreme gratitude for your photo.
If you want to follow my WIP, please see:
http://forum.sub-driver.com/forum/builder-threads/2938-1-144-u-boat-type-viic-41-knm-kya-ex-u-926
I'm converting that Revell kit (05100) into a R/C model.


I begun to look for infos about this boat in March 2015 and, after a while found that double profile drawing with "K-klasse etter ombygging" writing below.
That convinced me the boat was really converted because Eberhart Rössler's U-boot (ISBN8840373810) is vague about this.
So i started the project, still lacking some infos but looking hard for them in the www.
Found several U-klasse sub photos and, recently even this one:
http://digitaltmuseum.no/021015532143/motiv-k-klasse-undervannsbat-knm-kya-s307-med-ombygget-bro-1960-skipssjef-kapteinloytnant-h-b-ellingsen
Some photos of this database are not available and, guess wich?
http://digitaltmuseum.no/search?rows=72&type_filter=Photograph&query=kya


Best regards,
Frank
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2016, 10:51
Frank.
I see there is another thread discussing the KNM Kya. Kya Ex U-926 was a VIIC and not a VIIC/41 class. But she had an Atlantic bow and was the first VIIC  serving in the Norwegian Navy as from January 1949. We had three VIICs operating in the Norwegian Navy, one was a VIIC/41, KNM Kaura ex. U995. All three VIICs were modified before entering into the norwegian navy. One of the most visible change  was changing the conningtower casing allthough many believe this was just the old 1939 tower, it was different as can be seen from my image below.
I served as the engineering officer (chief engineer) on both KNM Kaura ex. U-995 and KNM Kya ex. U-926. and knew ltn.cmdr. Bjørn Ellingsen very well.
Neither the U 995 nor the U 926 were fitted with the balkongeraet when in frontline serving in the norwegian navy, they were fitted later, anyhow after 1956.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: zhuravlik on 10 May , 2016, 12:06
Mr. Tore,
Disregarding tower, wintergarden and hull thickness, wich are the main differences between VIIC and VIIC/41?
My intention is to build KNM Kya as the maximum evolution of a type VII i.e. with an idrodynamic sail and balkongerat.
Sort of european GUPPY program.


Best regards,
Frank
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2016, 13:09
Frank.
For a layman it is hard visually to see any outside differences between the two types VIIC and VIIC/41. The latter some tens of cms longer overall, mainly due to the atlantic bow which I guess is incorporated in the Revell Kit. The main difference is, as you say the stronger pressurehull and increased max. divingdepth. The stronger pressurehull increased the weight and as no change was made as to the mainengines some efforts was made to compensate this by removing and/or make lighter equipment whenever possible, but again no visible items. It might be that the max speed would be a fraction of a knot lower, but we did`t notice much difference. Some are of the opinion that the VIIC/41 had the new compass housing in front of the tower, generally not so, U 995 had the old rounded type although they have substituded this with the new type on the museums U-995, don`t use the museums U-995 as a reference as many details are unfortunately not correct.
The trouble to upload the images on this site is due to an upgrading they just had whereby all the images disappeared. They are busy with the problem, but I guess  it`s difficult to resolve. As a substitute they are going to make some sort off a gallery they told me.
 If you are in need of any images on my thread let me know and I get it for you.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: zhuravlik on 11 May , 2016, 06:46
Mr. Tore, you are very kind.
So, the hull's mold lines are the same.
I would need every sail picture you have because i need to draw a plan for Kya's hydrodynamic sail.
You say that balcongerat was added after 1956. Was the boat still in frontline service?


Best regards, Frank.





Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2016, 07:58
Frank.
The ex German VIICs finished in our navy as operational submarines 1960 and are since then was used for training and research. Unfortunately I don`t have any images of the new tower of Kya, but am aware of you needs and shall react if I get some. 
 As to the difference between the old standard VIIC bow and the Atlantic bow you may study the images below to check your buildingkit. Basicly the bow was raised a few cms and they put in a flare to the bow to improve the pitching behaviour in heavy sea. I guess there were several steps before the final solution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 May , 2016, 15:04
Another view of the "Atlantic Bow" on U-995...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2016, 23:34
Frank.
I just checked the Revell 05100 kit which is a VIIC/41 so it shall fit your requirement very well. Only make sure the schnorchel has a ringfloat air inlet on top, not a hinge type as they put on the museums U-995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2016, 00:41
As next step in the developement of the Kya sail (or fin as we say it) I am posting an image of the testing of the tower on the class which relieved our K class (VIICs). The name of my old Kaura S 309 ex. 995 was transferred to the new submarine S 310 KNM Kaura developed in cooperation with the Germans and named the Kobben class ( Seal class). Below is the final solution, this class is later relieved by the Ula class, which now is planned to be relieved by another new class. Submarines warfare is expensive.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2016, 03:12
One of my most read topics which disappeared during the last upgrading of the site was the effect on ballasttanks pressure related to the diving/surfacing angle of a VIIC. The standard correct divingangle should be about 7 degrees. An easy check on the correct divingangle would be as the top of the bridge wind deflector is at the watersurface the top of stern (in the RN called dutchess ass) should be at the surfacelevel as well. The relativly high pressuredifference between MBT 1 and 5 can easely be seen on my image below. At a moderate diving angle of 7 degrees there is a pressure difference between the floodgates of 0.7 kg/cm2. At a divingangle of 25 degrees you get a pressure differerence of 2 kg/cm2. Why is this important? Appart from the difference in stresses on the pressurehull, the requirement of blowing the ballasttanks changes, in case of an emergency blowing the MBT 5 would need 2 kg/cm2 higher airpressure (thus more air) to blow the same amount of water as on MBT1. If not adjusted the boat would get even a worse trim which might be dangerous.
When surfacing the ideal surface angle would be about 2 degrees by that the floodgates of MBT1 and 5 would be at the same level, 3.5 meters. This means when you start blowing the MBTs by exhaustgas  the counterpressure in boths tanks are the same, the saddletanks counterpressures however are the lowest so you start blowing these tanks ,then you switch over to the MBT 1 and 5 until you get the deepest MBT3 at an acceptable counterpressure.
When blowing the ballasttanks the air/gas takes the easiest way eg. the lowest counterpressure thus you have to compensate for the pressuredifference otherwise you bagger up your trim. This is why you have all the individual adjustingvalves in the controlroom for each ballasttank, both for exhaust and air blowing.
Tore



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 May , 2016, 18:48
Here is another one of Mr. Tore's drawings...
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 May , 2016, 00:29
The sketch shown in Dons post indicates another problem with a submarine as well. Apart from the obvious disadvantages of trapped air in tanks which might leave treatcherous bubbletracks you have the dangerous and undesired effect called the free surface effect. As long as a tank ( or compartment) is either full or empty there is no such effect, however when partly full of liquid there is an unstable situation as the center of gravity moves back and forth as the pitch, heave, roll, surge, sway or yaw varies. The effect might create a larger problem for a submarine than a surface vessel. To avoid this, the submarine is designed to limit free surfaces as much as possible, hence you have watercompensated fueltanks and try to keep the ballasttanks either full or empty. The residue venting of MBT 2 helps to fill the tank completely and thus to get rid of the free surface effect as well.


Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jun , 2016, 19:04
Hello Mr. Tore and All,


I uploaded "Skizzenbuch 11 x 17 - M + Index.pdf" to dropbox.  I added the Index to the back of the book and places the Index Page 461 in the Contents listing.  This website section looks to be fairly quiet for awhile.  I guess some time this fall I will be working with the publisher on the Type VII book.  Once finished, I may start another book on the Type IX C.  I currently have the drawings for the electrical schematics, and I have ordered the mechanical schematics from the Bundesarchiv via the Silke Archive Service in Germany... I believe we can make this website come alive again!  :) :)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jun , 2016, 01:30
Don.
I read you last version of the Skizzenbuch and like your pages having roman figures describing diving and surfacing procedures, which is correctly understood. One detail though, when diving and surfacing using the tanks, you normally are manning the diving stations. This means a lot of people are moving around particulary from the crew quarters in the fwd. torpedo room to the aft control room, engineroom and aft torpedoroom. This has influence on the trim and you have to compensate this by using the fwd and aft trimtanks. So prior to giving the orders divingstation, you pump water from aft trimtank to fwd. trimtank, our experience was you needed approximately 400 liters, to compensate for the moving of people. Hence the trimtanks take a part in the diving and surfacing procedure as well. Likewise when the battlestation (which are almost the same as divingstation) orders are given. When the situation is cancelled you operate the trim tanks in the opposite way. In fact when being submerged you reacted on the first order: "pump 400 liters from aft to fwd." realizing it will soon be followed by diving station.   
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jun , 2016, 09:18
Looking through old papers in my files I came over this cut I made from the french newspaper Le Figaro March 16. 1972. I remember it well, I was on  a business trip in France and with my hotelbreakfast I got the le Figaro morningpaper, to my astonishment I saw my old submarine KNM Kaura ex-U995 hanging in the air on the frontpage. I cut it out and saved it. For those of you mastering french you can read the story bearing in mind in spite of 27 years had passed since the end of WW2 there was still some feeling of the event of placing the submarine on the concrete foundation at Laboe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Jun , 2016, 15:26
Hello Mr. Tore,


During a dive you have people moving to their dive stations and you seem to indicate that 400 liters of water is pumped from the aft to the fwd trim tank to compensate for the change in the U-Boat's trim.  I believe I understand these trim adjustments.  all personnel will remain at their assigned locations while submerged.


However, during an emergency dive addition crew personnel may move to the fwd torpedo room to give the U-Boat an additional bow down trim to accelerate the diving process. 


1. Who gives the orders for that movement, or is it an understood procedure during an emergency dive?
2. Would they ever pump more water from the aft trim tank to the fwd trim tank for additional bow down trim?
3. Who would give such an order?
4. Who would act upon those orders?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Jun , 2016, 00:44
Don.
It could depend on the cause for the emergency. F.i. if the officer on watch while the sub being submerged has to make an evasive dive (collision or ramming danger) at periscope depth, there is no time to change  people,and you can`t use dynamic (hydroplanes) diving, steep angle, the officer of watch would order fill Q! An extra weight in excess of 4 tonnes gives a pretty good sinking effect and as Q is placed about midhips, there is no trimming moment and as people remains where they are, you don`t need to compensate using trimtanks.
If the officer on watch are free to to use dynamic diving he order the hydroplane angle and goes dynamically deeper and order pumping out water from the compensating tanks. Only in extreme using Q.
Thus emergency actions would not necessarily be carried out by diving station manning, but handled by the people of watch. But I can assure you, the CO and EO as well as the controlroom engineer would be in the controlroom  in a split of a second to take over.
Such procedures would be laid down in the CO orderbook and usually every CO would require to be called in immediately to take over.
Using the trimtanks to get a bow down for going deeper would normally not be done, you can do a lot by hydroplanes and it is very smooth.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jun , 2016, 22:28
Hello Mr. Tore.


I was thinking about adding this info to the Prologue: diving sequence...  What do you think???



"Using the trim tanks while diving or surfacing


During a normal dive procedure there are lots of people moving around particularly from the crew quarters to the fwd. torpedo room, the aft control room, the engine room, and the aft torpedo room. This movement has an influence on the U-Boat's trim and you have to compensate for this by using the fwd. and aft trim tanks. So prior to giving the order diving station, you pump water from the aft trim tank to the fwd. trim tank; our experience was you needed approximately 400 liters of water to compensate for the movement of people. Hence, the trim tanks take part in the diving and surfacing procedure. Likewise, when battle station order is given (which are almost the same as diving station) similar actions are taken. When the situation is cancelled you operate the trim tanks in the opposite way.


While on the surface, if the officer of watch orders an emergency dive, then we would have several things happening at once. There would be an order to pump 400 liters of water from the aft trim tank to the fwd. trim tank to balance the U-Boat, and then the crewmen are quickly manning their assigned diving station. In addition, there would be a mad rush of non-assigned crewmen to the fwd torpedo room. This would be the added weight of the human ballast to assist the U-Boat's bow in breaking the ocean's surface and getting the emergency/crash dive started expeditiously. The Q tanks would be of no additional assistance because they were already flooded while on the surface.


While submerged and the U-Boat is in a trim state; if the officer of watch has to make an evasive dive (collision or ramming danger) at periscope depth, there is no time to move people, and you can`t use dynamic (hydroplanes) diving, steep angle, the officer of watch would order fill Q! An extra weight in excess of 4 tons which gives a pretty good sinking effect and as Q is placed about mid-ships; there is no trimming moment and the crew remains where they are.  If the officer of watch is free to use dynamic diving, then he orders the hydroplane angle and goes dynamically deeper. Only in extreme conditions using Q. Thus emergency actions would not necessarily be carried out by diving station manning, but handled by the officer of watch. However, I can assure you, the CO and EO as well as the control room engineer would be in the control room in a split second to take over. Such procedures would be laid-out in the CO order book and every CO would require that he be called in immediately to take over. Pumping additional water into the fwd. trim tank from the bow trim tank, even in an emergency, to get the bow down for going deeper would normally not be done because you want to maintain the U-Boat's trim; you can do a lot by hydroplanes and it is a very smooth process."


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Jun , 2016, 01:28
Don.
The various procedures  on surface and submerged varies depending on the situation like weather, risk of be spotted, (airsuperiority) and are difficult to put down in a general rule. In the German navys Submarine commanders handbook for submarine ( U. Kdt. HDB) 1942, published by the San Francisco Maritime National Park Association, you`ll find the German Navy`s advices to their submarine commanders as of 1942.
I don`t think you should emphasize too much on adjusting the trim in emergency situations as time is the ruling factor. You are able to compensate the trim dynamically, and then using the trim tanks at a later stage.
Operating with the Q filled , I should think a risk of undercutting would exist. As you know the VIIC/41s and the some of the VIICs got the bow buoyancy tank and the Atlantic bow to reduce the undercutting risk, however with a low trim they encountered problems with the Junker compressor exhaust, all told, I would guess the use of low trim could vary between the various boats depending on their year and design. This is another discussion and may be it would be confusing to introduce in your Skizzenbuch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Jun , 2016, 14:49
Hello Mr. Tore,


How does this re-write look?



"Using the trim tanks while diving or surfacing


During a normal dive procedure there are lots of people moving around particularly from the crew quarters to the fwd. torpedo room, the aft control room, the engine room, and the aft torpedo room. This movement has an influence on the U-Boat's trim and you have to compensate for this by using the fwd. and aft trim tanks. So prior to giving the order diving station, you pump water from the aft trim tank to the fwd. trim tank; our experience was you needed approximately 400 liters of water to compensate for the movement of people. Hence, the trim tanks take part in the diving and surfacing procedure. Likewise, when battle station order is given (which are almost the same as diving station) similar actions are taken. When the situation is cancelled you operate the trim tanks in the opposite way.


While running on the surface, if the officer of watch orders an emergency dive, then we would have several things happening at once. The crewmen would immediate man their assigned dining stations, and there would be a mad rush of non-assigned crewmen to the fwd torpedo room. This would be the added weight of the human ballast to assist the U-Boat's bow in breaking the ocean's surface and getting the emergency/crash dive started expeditiously. The Q tanks would be of no additional assistance because they were already flooded while on the surface. Once they achieve the desired diving depth and dynamically level-off, then they can worry about balancing the U-boat when time permits. While silent running, compressed air instead of the trim pump motor is used to move water between the trim tanks if needed, thus eliminating the motor's noise.


While submerged and the U-Boat is in a trim state; if the officer of watch has to make an evasive dive (collision or ramming danger) at periscope depth, there is no time to move people, and you can`t use dynamic (hydroplanes) diving, steep angle, the officer of watch would order fill Q! An extra weight in excess of 4 tons which gives a pretty good sinking effect and as Q is placed about mid-ships; there is no trimming moment and the crew remains where they are.  If the officer of watch is free to use dynamic diving, then he orders the hydroplane angle and goes dynamically deeper. Only in extreme conditions using Q - this emergency action would not necessarily be carried out by the officer of watch. I can assure you, the CO and EO as well as the control room engineer would be in the control room in a split second to take over. Such procedures would be laid-out in the CO order book and usually every CO would require that he be called in immediately to take over."


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jun , 2016, 01:23
Don.
During normal diving procedure people take their divingstations which means people are moving from their quarters  to the divingstations, generally this means from the fwd. torpedoroom to the controlroom and engineroom. Thus people are not moving to fwd. torpedoroom, I assume this is a misprint in your text.
While running on the surface the general German instructions for crash diving advises no special trimming to be done as a VIIC  normally has a short diving time of 30 seconds, which you would need for disengaging and shutting down the diesels anyway, quicker than any preparation like moving people. Surfaced in enemy waters 1941 you had to be prepared for crash diving. Latter part of the 1944 you would be schnorchling.
During surface dieselcruising  I should think using the surface dieselspeed inert and hydroplanes would contribute to the shortest crash dive.Normally you would probably hold the venting of MBT1  a bit to assist the bow down angle. However it is up to the CO`s judgement to issue  the standing orders he may require in his orderbook. We usually kept the Q empty filling it only when needed.
I assume that your statement that the crew would immediate assume their assigned "dinnerstations" is a misprint. ;D
I guess as I said before, the various way to handle the sub depends on circumstances, experience and the CO.`s judgment, as well as the development of the strategical situation which is changing. Thus I don`t think you should going into accurate details how to handle the sub under various situations in your skizzenbook.
 In certain rare situations you may use people for trimming, I never felt the need for it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jun , 2016, 17:00
Hello Mr. Tore,


Understood, I will leave it as original...


Thanks,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2016, 07:18
Don.
Ok. As an additional info. I guess the submarine service of the German and the Royal Navy used Q differently, filling Q while cruising on the surface was seldom used in the RN, even if the RN submarines had forward folded hydroplanes above the waterlevel. Some CO`s might be tempted to cruise on the surface having the ballast tanks partly filled, a risky chance as the stability is reduced and the risk of undercutting is great. In the german navy partly filled ballast tanks was forbidden while cruising surfaced.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 09 Jul , 2016, 00:43
Hi Tore,


I have a question about the "wasserdichte Back" (bow buoyancy tank). Do you have a picture or a drawing how the tank looks in three dimensions? (please see attached jpg).


I find on eBay a photo of a damaged type seven bow maybe it would be helpful to answer the question:
http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-302-NACH-DER-BUGKOLISION-KOMMANDANT-HERBERT-SICKEL-/231999050226?hash=item36043891f2:g:JV0AAOSwxvxW7dgu (http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-302-NACH-DER-BUGKOLISION-KOMMANDANT-HERBERT-SICKEL-/231999050226?hash=item36043891f2:g:JV0AAOSwxvxW7dgu)


Thanks in advance and best regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2016, 02:27
Falo
I am sorry I don`t have a 3D drawing of the bow boyancy tank. Looking at the sketch you posted I guess you have reduced the wasserdichte- back a bit too much. In general the tank is placed between frame 102 and 113 and goes out to the bowcasing.This means that the HP flask is inside the tank and I guess the anchor chain goes via a chainpipe to the anchor bay. As you probably know the tank has freeflood slits in the bottom and vent on the top. Right fwd of the tank is a forepeak, kind of small collision peak. See my sketches below. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 09 Jul , 2016, 04:27
Hi Tore,

thank you very much for your fast and detailed reply.

Sometimes I wish I could drive to Laboe with a big can opener in my instrument case to open the outer hull of U-995 and photographing every small part of the inner structure. After that project I will post a very detailed photo report here, promised  ::)

Thanks again and egards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2016, 05:07
Hi Falo.
Crawling inside the casing of U995 would not give you much info. I believe it i is almost an empty space as painting and maintaining this space is very difficult. When I was the EO of U995 I crawled all over and as I used to be a skinny guy, I got access to everything, today age and kilos would effectively prevent this even with a can opener! ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Jul , 2016, 14:33
Hello Mr. Tore,


Well, I'm starting a new project "Skizzenbuch: U-Boat Type IX C Project"...  I have attached Image 045.jpg which looks to be very similar in design and functionality to the Type VII C compensating water system with the water source coming from the Diesel Engine cooling water.  What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Jul , 2016, 00:53
Don.
IXC type is of course a bit outside this thread and I have never served on a IXC, but still it is interesting to make a comparison between VIIC and XIC. When comparing the watercompensating system, I agree there are a lot of similarities however as can be seen on my sketch below the external compensating water of the IXC seems to have a common supply pipe from the silencer/sparkarrestors to the headertank and the external fueltanks, which simplify the system. The internal system is basically the same.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Jul , 2016, 16:02
Hello Mr. Tore,


My Type IX project will take a year, or more, to completion... Can we use the current mail box, or should there be another Tore's mail box created for the Type IX U-Boat? There doesn't look to be anything really different between the two types of U-Boats.  I'm sure with my new found knowledge and input from you, Maciek, and others, we could have an interesting topic and great informative discussions. What is your advice?


Regards,
Don_   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jul , 2016, 00:25
Don.
I have of course no objection to include IXC in this thread. As to my contribution, I am afraid it would primarily be theoretical, based my VIIC and general submarine knowledge as I don`t know the IXCs in details. However as I said it might be of interest to have a discussion about the difference between the two types VIIC and IXC. As I have practical no manuals, drawings or books on the subject it might be convenient if you put forward the topics you would like to discuss enclosing the relevant attachments. You could perhaps start with the basics like development history, physical dimensions, GA plans, rudder and hydroplanes, periscopes, torpedo arrangement, main engines and E-motors etc. if you have details of same. I am sure apart from our old friends, there are people out there having substantial knowledge of the IXC, and although very similar, a discussion of the difference between the two types could have some interest I guess.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 31 Aug , 2016, 03:21

Hi Tore, Don, Maciek.  I am new member to this forum and hope if you don't mind for me asking a lot of silly question about the operations of VII.


A little introduction about me. My name is Karel and i am in the same situation like Mark, i am also developing a submarine game. Only i am not trying to recreate physics and 1:1 since my experience will be a bit different. It is a game that is played trough virtual reality headset (Oculus Rift and HTC Vive) and will have a multiplayer element. What i am trying to achieve is to recreate the feeling of being inside the submarine. For the past 2.5 years me and my team have been recreating the Interior of VII u-boat. Since the game is built ground up for virtual reality, we had to turn a lot of attention to all these small details. Of course we cannot recreate 100% of the interior details with the top visual quality because no computer would be able to play them. (VR game needs to run 90 frames per second) 


As for the gameplay. Since the game can be played alone, or with a friend we wont put player trough heavy process of an actual submarine control. Its too complicated and would need more people. Since players are in virtual reality and have hand controllers they have to physically turn all those Valves and vents. So instead we are going for the easier and fun route where 1 player can manage the control of the U-boat if he needs to. But.. this opposes another problem, since we want the u-boat interior to feel authentic we still want to model at least 60-80% of all the control elements and. Easy fix for them would just to have these as props, an eye candy that cannot be interacted with. Again problem is that in virtual reality if you already have some interaction build for certain valves, then user automatically will assume that everything is intractable. So we decided that every valve has to have some sort of meaning, so when player turns a valve that regulates oxygen levels in different compartments then he/she is able to do so. We can easily add some sound feedback, like a hissing sound that travels trough the oxygen pipes. This will give no affect to gameplay itself but still adds agency to the player making him/her feel that every action has a meaning (even if this meaning has no gameplay value)


Other aspect would be purely educational. They could walk around the boat and learn the meaning of every operation that was done inside the u-boat.  What i would like to avoid is making a gross errors like confusing flood valves with oil valves and etc.


https://www.youtube.com/watch?v=hYMoLe5ZSaQ (https://www.youtube.com/watch?v=hYMoLe5ZSaQ) - here is the video of the game.  It is still a very much a work in progress. Also do not mind, no operation there is historically correct. I needed a prototype asap and many of these things were made up for speed purposes. Now that our u-boat is in the finishing stages it is time to start researching about the controls.


So this is the reason why i joined this forum. I found you brilliant people and was hoping to ask many many questions about what some or other instrument inside the u-boat does. Then i could use this information to create a "semi-realistic" virtual tour of the u-boat that has all the objects intractable.
I am aware about the book that Don is making and it would save me months of research work but sadly it is not available yet.
So i am hoping that you gentlemen do not mind if i stick around and ask many questions.


----Questions


My first question about all those lost image materials that come before page 200. Are all these lost, i cannot see them? When i download the attachment they seem to be broken. Seems that the site was offline and after coming back all this information is lost?


My second question is about attacking other boats. As i understand that neutral buoyancy was almost impossible to achieve. Does that mean all attacks trough the periscope must be done when boat is moving because then hydroplane operators can fine tune the depth?


Third question is about the ballast. When i am filling all MBT1,2* MBT2, MTB3, 2* MTB4 and MBT5 100% and not touching the negative buoyancy tank.  How deep does the boat go until it starts to approach its neutral buoyancy?


Thank you. And i apologize for the wall of text :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Aug , 2016, 09:36
Karel, welcome to the forum and my mailbox, I admire you intentions and shall try to help where I can. I am afraid the lost images up to page 200 is lost due to a crash of the system but the knowledge is  here and I have quite a few of the images in my file so just shoot you questions and we`ll see what I can do.
Second question. Neutral buoyancy is not necessary for attack in fact sometimes not even desireable. If your submarine is weightless it requires a small force to move it and your are unstable. As in open sea you generally have swell and waves moving the submarine you want to counteract these movements by dynamically controlling ( by hydroplanes and speed) the submarine. Attacking at periscope depth is the most common attack and you are relying on your hydroplane operators and the trim. The trim (regulating tanks are filled according to experience, calculation and weather) and the hydroplane operators using their hydroplanes watching the Papenberger, a depth gauge having a scale where you can read the position of the attack periscope in relation to the sea surface. See attached image. I guess the only time you are using a accurate neutral buoyancy is when hiding either for escape or observation. You search for an interface between to different densities of water ( sonar mirror), put you submarine under the layer, adjusted to neutral buoyancy trim, shut down all machinery (dead silent) and adjust minor differences in displacement by lowering and raising the periscopes. This can be done silent if you top up your hydraulic accumulators and use the stored hydraulic energy to lower and raise the periscopes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Aug , 2016, 15:06
Karel, I realize I forgot your third question. When the main ballasttanks are not used for fuel, they are only used for diving the submarine and do not participate in the trimming. Prior to the diving, the regulating tanks are adjusted to the calculated desired trim submerged at the requested depth. When diving requesting a quick dive you use the Qs ( Untertriebzelles) to overcome the "surfaceresistance" for the first part of the dive. The Qs are blown as soon as you are submerged, generally at some 8-10 meters and the submarine is at the right trim at the required depth if the regulating tanks are adjusted correctly, if needed the regulatingtanks can be corrected when submerged by the main ballastpump. If you want to take the submarine further down, the pressurehull is compressed and the displacement is reduced and you loose buoyancy, this has to be compensated by pumping out water from the regulatingtanks 1 and 2 port and stb. corresponding to the loss of buoyancy. For a VIIC this would be about 100 liters seawater per 10 meters. As you probably know, a pair of the regulatingtanks 1 can be used for fuel, which reduces the flexibility of the regulating tanks when in fuel configuration. The same happens when MBT 2 and 4 port and starboard are in fuelconfiguration, which means the ballasttanks are partly filled with diesel fuel having a specific weight less than seawater. You have to compensate this by using regulatingtanks 2 port and starboard which cannot be used for fuel. All told, the regulating tanks plays an important part in the trimming of the submarine and not the MBTks as long as they are not in fuelconfiguration.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 02 Sep , 2016, 06:41
Thank you Tore. Based upon your feedback i think that i have made pretty good diving system for my game. Its not 100% realistic, but still has some complexity and is not "push one button to dive" system.

About the tanks itself. I read somewhere (possibly in this thread) that all the diving tanks had to be empty or full. There was no in-between solutions like only flooding 50% of a certain tank. Why was it that way? Did the boat become unstable?

Another theoretical question about neutral buoyancy. It may be confusing but i try to explain. I apologize if i do it badly :)

Lets say commander achieves near neutral buoyancy with the slight force that moves the boat up. Is the upward momentum a continuous force and the boat will eventually reach near the surface? Theoretically i think that the upwards movement should continue to happen until the boat reaches shallower depth where pressure is smaller, and the weight from ballast tanks will become an issue again and makes the boat sink again.
Is this right?

Thank you.  Btw. I love your name. Tore in my native language means the word "great" :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Sep , 2016, 10:02
Karel.
The reason for having the tanks either empty or full is to avoid what we call the surface effect. When you have only partly filled liquid in a container which is moving you get a rapid shifting of the center of gravity of that tank as you create a local wave in the container and a submarine is susceptible to these movements. To avoid that, you keep the tanks for liquid either full or empty. As a consequence of this effect all the fueltanks are always full eg. seawater compensated, meaning you let the seawater fill the empty space left when you are consuming the fuel. The fuel " float" on the top of the compensating water as seawater has a higher specific gravity. In those cases where you cannot avoid partly filled tanks, like regulating tanks, you "chop up" these movements by fitting ripple/splash bulkheads in the tank allowing the liquid to move but only in smaller quantities. Further you try to place these tanks as close to the submarines gravity/buoyancy center as possible reducing the impact moments. There is no in between solutions, but as you gradually fill the fuel tanks and the ballasttanks in fuel configuration with seawater, the weights and moments changes thus you have to calculate and adjust that by the regulating tanks and some times even trimtanks.
If the submarine is having a slight positive buoyancy at a certain depth, it don`t only ascend, but shall have a slight acceleration upwards as the hull is expanding increasing the displacement. If any residue air is left in the ballasttanks this air shall expand as well and force the ballast water out of the Kingstons increasing this acceleration. Eventually the submarine shall break the surface sometimes higher than equilibrium due to inertia forces before she rest on a surface draft corresponding to the weight /displacement balance. This could be an uncontrolled  stability position as the MC (Metracentric centre) is changed. As you know this procedure take place when surfacing, you raise the submarine dynamically to periscope depth, then by HP air blow your MBTs only partly to save HP air resulting in being only semi surfaced and unstable before you start blowing, by the diesel exhaust, the main ballast tanks at a certain sequence until you are fully surfaced.
As to my name your native tongue is not far off. The name is from the Viking god Tor, who is the God of thunder and lightning. I guess he was pretty big. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Sep , 2016, 12:45
Hello Mr. Tore and All,


My wife, Maureen sent me this link from her cell phone...  The final resting place of U-576 a type VIIC that was lost in 1942 off the North Carolina coast.

http://www.dailymail.co.uk/news/article-3774630/The-ghosts-U576-German-U-Boat-30-miles-coast-North-Carolina-72-years-sank-Nazi-campaign-terror-44-soldiers-entombed-inside.html


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Sep , 2016, 15:00
Don. Reading the newsarticle I noticed they state the wreck was located August 24. 2016. I guess it has previously been published she was located 22. October 2014. One of her ballasttanks was damaged, hampering her diving and surfacing capabilities prior to her last attack. I guess the damaged tank could probably  have been one of the saddletanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 07 Sep , 2016, 06:46
Tore.

Thank you for explanation. I added this behaviour to my diving system. I have read the word "Kingston" here a lot but since pictures are gone it is hard to put it into context. Is this some kind of valve? Do you have a picture of it?

Also trying to figure out submarine speed. Wikipedia says that under water the max speed was 7.6 knots. Was that speed always constant or did it decrease when submarine went deeper? Could it actually run at 7.6 knots when at 155-200 meters?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Sep , 2016, 07:41
Karel. Kingstons are named after a British engineer living in the latter part of 1700 who invented the valvetype. It is merely a bottom valve allowing sea water to enter into any ships hull. For a submarine this means specifically the bottom seavalves of the ballasttanks allowing seawater to enter the tanks when diving. Kingston are usually always open when the submarine is at sea and shut when alongside in the harbour for safety. They are cumbersome to operate by removeable cranks which are placed on the square of the valvestems, usually in the controlroom. Theoretically you could sink a submarine if laying alongside by opening the ballasttank vents if the kingstons were open. Sometimes you would shut the Kingstons when depthcharged preventing the shock waves to enter the ballastanks. Below is my model of KNM Kaura ex U-995 showing the Kingstons in this case square flapvalves in the bottom of the saddletanks and MBT 3.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Sep , 2016, 08:13
Karel. Speed of the VIICs submerged . Speed submerged (or may be the water resistance) is not changing noticeably within the submarines operation depth range, and depends thus primarily on the power available at the propellershafts. The VIICs and many of the WW2 submarines had a low submerged speed as the e motors did not have the powers to exceed the speed mentioned by you. The German submarine tactic "Wolfpack"  would be to gather several Uboats where they assume a convoy would pass, carry out the attack requiring slow speed. After  the convoy passed, reload the torpedoes, when ready, proceed on surface at high speed 17-18 knots overhauling the slow convoy  (7-12 knots) by powerful diesels, dive ahead of the assumed course of the convoy and repeat the attack. Modern submarines of today are differently designed and adopted to different tactics which requires higher speed submerged.
The E-motors were not a constant power motors and the speed and direction of rotation varied, in fact as the diesels of the VIICs after 1942 had the reversing removed, the E-motors were the only motors used for maneuvering able to revers and having variable speeds. Finally the e-motors were used as generators as well, driven by the diesels charging batteries solely or combined when diesel cruising on the surface.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 08 Sep , 2016, 02:15
Great piece of intel, beautiful uw footage shots and original b/w pics, Don. Thank your wife on my behalf!
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 08 Sep , 2016, 08:58
Really good information  ;)


So i think that my diving system is pretty good at the moment. Played in virtual reality today and the new diving system added a new dimension to the gameplay. Instead of going to x depth and calling it a day, i know have to keep the boat in balance and in trim. If i constantly do not watch and adjust my bearings i risk to sink the boat or surface. Lets just say that evading a depth charge became much more complicated. Hopefully i can get multiplayer working correctly so people could divide up the tasks in the sub. Running alone in sub, adjusting instruments, keeping track of the enemy and evading, even though it is all super simplified it can be a daunting task to handle alone.


Tore. Are you able to tell me how fast did those tanks filled up with water? I guess different tanks had different speeds since their size were not the same.  I am mostly interested in tank3, tanks 4 and 2, tank1, tank5, and negative tank. These tanks are represented in my game.
I also have a trim tanks represented in the game that shifts gravity from one end to another if needed. As for gameplay reasons i had to add another "special unrealistic cheat compensating tank" that just holds the boat at neutral buoyancy at periscope depth. Otherwise it would be impossible to play this game as a single player experience since you would need to constantly jump between the hydroplane controls and periscope.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Sep , 2016, 11:47
Karel. You cannot fill the ballast tanks independently as you shall upset the trim both atwartship and alongship. What matters in real life is how fast you can dive in emergency. The ballasttanks 2, 4 port and starboard as well as MBT 3 have all Kingstons dimensioned  for the capacity of the tank and a quick filling, MBT 1 and 5 have no Kingstons but free flood gates with ample dimensions, adopted to the quickest diving time. All the MBTks particularly MBT 2 and 4, and MBT 3 have quick vents by pull down handles, MBT 1 and 5 by hand wheels, all situated in the controlroom.
 An optimal quick dive can be obtained by following a special procedure. When approaching hostile waters you fill the Qs and increasing the draft, but primarily to assist to overcome the "surface resistance", the regulating tanks adjusted to the COs request for a buoyancy at a particular depth. At the order for an emergency dive you open the vents for MBT5, MBT3,MBT2 and 4 port and stb, for MBTs 2 you open the residue air vent waiting to vent MBT1 to assist the bow down angle. When the boat start to dive bow down you normally open the vent for MBT1, the boat is controlled dynamically ( by speed and hydroplanes)at angle of 8 degrees to prevent the stern to be  too high above the surface, a rough control by the periscope would be the towers wind deflector is at the sea surface simultaneously with the aft end of the boat. At 8-10 meters you blow the Qs and the boat has a required buoyancy at f.inst. periscope depth. By following this optimal procedure you can obtain a diving time of 30 seconds which is pretty good and considerably quicker than f.inst. a IXC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 13 Sep , 2016, 05:06
Really appreciate your input Tore.

Few questions about regulating tanks. When you need to correct your regulation when submerged, you can do it so at the main ballast pump. Can you give me a brief explanation how this was done? I am looking at the screenshot and see bunch of red valves lying on the floor. Did these Valves all work in a combination? Lets say i need to pump more water to aft and thus only rotating certain Valves.
Also doing trim when you are surfaced. Did you use same valves or was the trimming on surface done differently?

Thanks,
Karel
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2016, 08:39
Karel.
The regulating tanks are used all the time and the operation of same is in the controlrom. The regulating tanks can be operated in many ways by:
1. The main ballast/bilge pump being a two stage sentrifugal pump. The 2. stage used to discharge to sea at greater depths. 
2. The trim/aux. bilge pump being a pistonpump.
3. By hp air.
Further regulating tanks 1 can be used as fueltanks as well.
This require a somewhat complicated pipe and valve systems to handle all the alternative and fairly confusing to a layman so I guess I should start with alternative 1. being the most common.
 On my image below you see the pipesystem for the main ballast pump, capacity 1300/1465 liters / min. against 15 meters. and the 4 regulating tanks in seawater configuration, green regulating tanks 2 and yellow regulating tanks 1. Corresponding pipelines coloured as the tanks. On the photos you see the valve chests with valves. If you want to pump out regulating tank 2 port and starboard with say 100-200 liters, you probably would like to use the smaller aux. bilge/ trimpump having a capacity of 300/360 liters pr min. You open the valves for the yellow pipeline, and discharge to sea, via the boardvalve b , in this case you may read the amount discharged on the watergauges  for reg.tanks 2 port and stb marked off per 100 liters, indicated on the image below. In case you are afraid of leaving an oilslick on the surface you don`t discharge to sea, but into MBT 3 s boardvalve (dotted pipeline) on the drawing.
If you want to fill more seawater into the tanks, you don`t use the pumps but merely open the sea valve "a" and follow the volume on the water meter in the pipeline till you have the correct amount into the tanks. The regulating tanks are vented into the controlroom as can be seen on the system drawing.
The above system is used both on the surface as well as submerged.The valve are indeed used in combination, but not mechanically interconnected.The forward aft- trim is a separate system and although you use the same pumps, you have forward and aft trim tanks, the pipelinesystem is different but interconnected. Both systems can be operated by compressed air as well.
It might require some studying of the of the different systems to have a full understanding. I fully understand the difficulty to have a 100% correct understanding, but these systems are very important in a correct operation of a submarine so just ask your questions.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 13 Sep , 2016, 11:31
Hello Tore!

I joined this forum so I could say "hi" to you and to say thank you for participating in this forum and thread to tell us what it was like operating a German u-boat!

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2016, 11:42
Steve thanks, if you have any questions, shoot I am going on 88 so don`t hesitate ;D !
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 13 Sep , 2016, 13:12
Hi Tore!

Thanks!  To be honest, one of the reasons I jumped in here so quickly when I discovered this thread was to be able to say hi and thanks before you were gone!  I am 46 years old and over the years there have been so many people of historical note that I wished I had had a chance to speak to that were gone before I realized I had the chance to do so. 

For example, I have been trying to get an address for Rienhard Hardegan, who is like 103 years old and supposedly still resides in Bremen, to send him photographs of the Silent Hunter 5 u-boat simulation program, to show him what people are up to these days in remembrance of their deeds of long ago. 

I have long been a fan of the Silent Hunter series of PC uboat simulations, having played them for a decade or more now.  Plus other uboat sims before that.  I have just now undertaken building the Revel VIIC/41 Atlantic Version and so have been inspired to hunt down internet sources for ideas.

I have opened up the long flood opening above the saddle tanks and am adding ribs as many modelers do.  I want to replace the "box" around the snorkel recess area with appropriate deck support structure.  Are there any pictures that show this area of the uboat without the decking in place?

I am slowly working through this long thread - I am on page 8.  Sadly many of the referenced links and even attached pictures no longer work.

Thanks and nice to meet you,
Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 13 Sep , 2016, 14:50
Another question:

On many models, and on the U-995 museum ship, at the point of the saddle tanks is shown a "drip rail" with holes just above it for draining.

It would seem to me that this would be underwater at all times while the boat was in service.  Is the drip rail something added after permanent dry-docking?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2016, 15:07
Steve, do away with the gutters installed on the museums U 995 they were of course not on the original. Reverting tomorrow with the schnorchel details in the casing, do not copy the museums U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2016, 23:56
Steve.
Recess for schnorchel mast. I dont think you should make a box for the schnorchel recess. I have seen a couple in the IXC casing. just a box around the schnorchel head, made of plain thin steel plates having drilled holes, I can`t remember we had such a box. When the schnorchel mast was lowered, it rested on cradles fitted on the pressure hull, right above the COs cabin you had a lockingclamp entering an eye on the mast. The clamp had a spindle going into the top of COs cabin ending in a handle to lock the mast in resting position. Otherwise the space around the mast was pretty empty just surrounded by angled thin steel girders and steel supports for the casing and wooden deck.
 The raising cylinder and crank was quite different from to days museum U- 995 mock up as can be seen on my image below. The whole thing was half way above the casing deck. As a bonus I post an mage of me inspecting the original schnorchelmast of KNM Kaura ex. U 995 some time in 1953.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 14 Sep , 2016, 02:45


Thanks. I think got enough out of it (after reading carefully 5 times) in order to figure out how to fit a simplified version to the game. So i have been trying to research about all the valves that are located in command room. We have most of them modelled out in game and i would like to know what did they do so i could give them a right functionality.

This is from my research from all various sources. Sometimes they conflict badly and they are probably wrong.

On screen1
1) Flood ballast tank2 stb
2) Flood ballast tank2 port
3 and 4)  No idea. Something to do with oxygen?

On screen2
1,2,3,4 Somekind of emergency flood crank to quickly fill up tanks. I think one of them were MBT3 or MBT4&2
5,6 - Valves to close/open air intake pipe that goes into engine room? The one that almost caused a serious accident on your patrol when someone forgot to close them and added 5 tons of water when the boat was diving.

Again, many many thanks. For these past few weeks i gathered more information from you than any other source where i did research for months.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 14 Sep , 2016, 07:32
Quote
Recess for schnorchel mast. I dont think you should make a box for the schnorchel recess. I have seen a couple in the IXC casing. just a box around the schnorchel head, made of plain thin steel plates having drilled holes, I can`t remember we had such a box. When the schnorchel mast was lowered, it rested on cradles fitted on the pressure hull, right above the COs cabin you had a lockingclamp entering an eye on the mast. The clamp had a spindle going into the top of COs cabin ending in a handle to lock the mast in resting position. Otherwise the space around the mast was pretty empty just surrounded by angled thin steel girders and steel supports for the casing and wooden deck.

So basically the floor of the "box" is just the top of the pressure hull, right?

In this version of your photograph, which I found in Foxbat's build thread, you can see a little bit more of the snorkle.

It appears that there might be some kind of platform that the snorkle is lying on elevated just slightly above the pressure hull?

(http://i.imgur.com/gfyawft.jpg

Steve)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Sep , 2016, 12:21
Karel.
It is not easy to go into valve and vent details in the control room. I am afraid you got it a bit wrong. May be we should go back to the basics. What makes a submarine dive are the main ballast tanks, they are therefore controlled from the control room. For a VIIC you have 8 main ballasttanks MBT1, 2 port and stb. 4 port and stb, MBT 3 which is having a central bulkhead making it port and stb although it is basically the same tank and MBT 5. At the same time we have two buoyancy tanks situated in the bow and the stern. They are not considered as ballast tanks as they are originally designed to give extra buoyancy on the surface to reduce pitching, nevertheless they have to be vented when diving, so you have to open the buoyancy tank vents as well. Contrary to many other submarines the VIICs was  equipped with mechanical operated vents , and when you would have the controls in the control room this means that the forward and aft vents had to be operated by long rod transmissions  going through bulkheads and compartments. A cumbersome arrangement which require a lot of maintenance and greasing. Below I have made a drawing using one of  Simon Morris excellent images as a base in order to explain what I am trying to say. Hopefully the image and text shall give you the answer. Unfortunately I had to split up the drawing as the file is too large. Just ask if something is unclear.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 00:48
Karel.
I realize the residue air might be a bit unclear. When you have a steep angle bow down diving , it is difficult to vent the aft MBT 2 port and stb as air would be trapped in the aft part of the tanks, colored yellow on my sketch below, hence an extra venting pipe ( yellow) and a common port and stb vent for the aft part of the tanks, operated by a long rod from the control room.
I forgot your assumption on the smaller bulkhead wheels, this has nothing to do with the diving, they are the shut off bulkheadvalves for stb and port ventilation ducts.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 01:38
Steve.
Schnorchel mast recess in casing. Below is an image showing the original U 995 execution VII/C 41 of the schnorchel with locking pin in lowered postion as well as raised.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 02:51
Karel.
Finally, your screen2. You are right in your assumption as to valve 6, this is the diesel air supply main intake valve going via a pressure proof duct outside the pressurehull to the board valve in the engine room ending near the bilge on each side of the diesels. The smaller wheel is for the ventilation system going in the same way to the ventilation intake valve and ventilation fan in the engineroom. The reason for having two air intakes is the diesel air system was susceptible to seawater flooding in bad weather hence the outlet ending in the engine room  bilges, a complete separated system with ample draining was used for the ventilation system to prevent seawater penetration and damaging the electric fan motors.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 15 Sep , 2016, 05:39
Tore.
Just to make sure i understand right. The "long rod transmission"  this means these rods (1,2,3,4) that are on the upper hull on screen2?

I hope that i am getting this right.  The rods number 1 and 3 are for opening vents for MBT 2&4 port and stb. The rods 2 and 4 are opening MBT3 port and stb.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 06:36
Karel.
I am afraid, not these are pull down handles for MBT 3 stb and port, the long rods for mechanical opening of the forward and aft vents are indicated on the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 15 Sep , 2016, 07:28
Thank you for explaining the rods. Now i understand the context better and am able to fully understand your description.


Do you have pictures of handwheels for aft buoyancy tank?
I am also unable to locate the handwheels for negative buoyancy tank port&stb. If i am not mistaken then these tanks itself should locate between regulating tank and MBT4. I guess their handwheels should also be in command room somewhere.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 08:21
Karel. You could not pick a more complicated item. When the Junker free piston compressor was installed in the aft torpedoroom of the VIICs they experience problem with the exhaust back pressure of the Junker compressor. In order to solve this, they made an interlock with the aft buoyancy tank vent so you could not open the exhaustvalve unless  the buoyancy tank vent was shut, preventing the stern to be too low in the water, hence the complicated arrangement as can be seen on the image below. However your question as to the location of the vent handle you`l see same on my images, as you see, this vent cannot be  operated from the control room.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 08:47
Hi Tore!

Thanks for the replies on the snorkel.

So if I am interpreting the illustration correctly, the snorkle rests directly on the pressure hull when in the lowered position.

So, on my Revell 1:72 model, I am building the pressure hull and saddle tanks under the deck in that region, and I will omit the "box" structure provided with the kit, except for the hinge section.  I will build in appropriate deck supports around the opening.

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 08:55
Steve, I guess you`ll be well off with such a solution.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 08:57
So what would you say is a ballpark number of valves that had to be manually opened/closed every time you dove or surfaced the boat?

It seems very complicated!

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 09:04
Steve. All the valve were manually operated. Kingstons, vents, exhaustvalves etc. I guesstimate some 30- 40 vents/valves altogether including valves for HP blowing and exhaust blowing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 09:07
Quote
Steve. All the valve were manually operated. Kingstons, vents, exhaustvalves etc. I guesstimate some 30- 40 vents/valves altogether including valves for HP blowing and exhaust blowing.

Cool.  How many people were required generally to operate all the valves?  Seems like a lot of coordination is required!

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 10:52
Steve.
 Diving would require some 7-10 people operating the vents manually, further 3-4 men in the engine room shutting the hull valves. Surfacing, one man, the control room engineer at the blowing panel as many of the HP air valves were adjusted on beforehand allowing only the main blowing valve to be operated. No men at the vents as the vents are shut when submerged, however in war time the vent operators would be stand by at diving stations. Each man knew exactly what he should do, the drill was done during the work up periode and you did not give any other order than dive, dive, dive, the coordination was done on beforehand. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 11:58
Quote
Diving would require some 7-10 people operating the vents manually, further 3-4 men in the engine room shutting the hull valves. Surfacing, one man, the control room engineer at the blowing panel as many of the HP air valves were adjusted on beforehand allowing only the main blowing valve to be operated. No men at the vents as the vents are shut when submerged, however in war time the vent operators would be stand by at diving stations. Each man knew exactly what he should do, the drill was done during the work up periode and you did not gave any other order than dive, dive, dive, the coordination was done on beforehand.

Fascinating stuff!  Did the German u-boats have a "Christmas tree" like the US subs to indicate the status of all the valves?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 14:39
Steve.
Christmas trees were common on the VIICs, below is an image of the blowing panel, as you probably know the VIICs used HP air for blowing the ballast tanks, the blowing christmas tree consisted of a common blowing valve for all the ballasttanks, each tank could be individually adjusted  as nessesary by a separate valve after the main blowing valve, which of course resulted in a lot of valves. In order to save HP air you only blew the main ballast tank partly by hp air and continued blowing the residue by exhaust from the main diesels. The system required a constant adjusting of the exhaustblowing as the resistance varied because the ballasttanks were situated at different depth and thus the counterpressure varied, if not adjusted the exhaust would only work on the tank having the lowest counterpressure. Thus you must be able to distribute the exhaust to the right tanks. This panel or christmastree if you like, is situated outside the pressurehull having the adjusting valve wheels on top of the blowing panel as can be seen on the image.You started to exhaust blow the the MBT 2 & 4 being closest to the surface (least resistance ), then shut the valves to MBT2&4, continued with 1 and 5 now having the lowest resistance and as the submarine ascended shut the  MBT 1 and 5  and finishing up with the MBT 3 the (deepest tank highest resistance ) now having an acceptable resistance, until you was completely surfaced. This required a constant surveillance by the operator and a frequent adjustment of the valves in the exhaustblowing panel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 15 Sep , 2016, 14:43
Quote
below is an image of the blowing pane


Your forgot to add the image.  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 14:49
You was too quick, I had the image loaded but it was too large and I had to make it smaller hope everything is OK now.
tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 14:59
Hi Tore,

That is not the kind of Christmas Tree I was talking about - on US subs they had a series of red and green lights (like are on a Christmas tree, thus the name) that indicate the open/closed status of hull valves.

Here is one from the USS Drum (Gato class):

(http://www.drum228.org/img/drumchristmastree.jpg)

Steve

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 15 Sep , 2016, 15:01
Tore:

In your picture of the VIIC Christmas Tree, why do some valves have rope windings on the handle?  Do they get hot/cold from the air passing through them?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 15:31
Steve. I thought you used the same valvecluster nomination as the offshore oilexplore people which is a stack of valves on top of an underwater oilwell. No the VIICs did not have your type of xmastree the closest I can get is the light controlpanel for the essential hullvalves as on the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Sep , 2016, 23:52
Steve. The valves on the blowing panel were of a special construction having a valve cone designed as a reduction valve. The green handle wheels were the HP group valves direct connected to the HP flasks max. 205 bar. or slightly in excess of 2900 lbs/sq.inch. The main blowing valves reducing the pressure from max.205 to max. 25 bar and the distribution valves reducing the pressure to appropriate adjusted pressure for the relevant ballast tanks. The rope windings on the handles are insulation, this can be seen in particular on the exhaust blowing panel. The dieselexhaust valves gets hot, the HP air reduction valves get cold.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 16 Sep , 2016, 02:10
The name christmas tree was also confusing for me when i started my research. In U-boats the christmas tree was referred as the blowing panel. In US submarines the christmas tree was the indicator panel.


Tore
The last picture that you posted. I see one big red handwheel on upper hull. Between the green and grey valves. Do you know the purpose of that handwheel?
Also about the red blowing valves. Currently my game the main blowing valve working but i would also like to add the functionality for these smaller adjusting valves for individual ballast tanks. Can you help me identify them?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 02:51
Karel.
The large red wheel is the common blowing valve of the stb. and port Q tanks ( untertriebzelle). The wheel with a black rim is the stb Kingston ( floodvalve) for stb. Q. A similar Kingston is used for the port Q as well. The system consist of a cross over pipe to the port Q tank and is, in addition to blowing, used for venting the Qs inside the submarine via silencer as well. The port Q has a separate Kingston (flood valve).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 03:09
Karel.
 I discovered you ask me a question in another thread on canning. I guess you asked for the image of U 995 taken May 1945 in Trondheim. Below is same and practically no visible canning occurs in spite of a heavy war duty for almost 2 years in the Barentz Sea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 16 Sep , 2016, 03:27
Karel.
 I discovered you ask me a question in another thread on canning.


Tore.
It probably was not me asking that. I have only been active in this thread.

About q tank floodvalve. You mentioned that similar valve was at the port side. I added a screenshot. Is this the valve for port Q tank flood?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 04:35
Karel.
Although the image is a bit dark but it looks like the port Q kingston. I am posting a new image showing the Q pipe/ valve arrangement at port side next to the chart table.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Sep , 2016, 05:57
Tore, could you explain how the light panel works and how its appearance change when in use?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 16 Sep , 2016, 06:06
Yes, that was the one. Thank you. So i now have the handwheel and lever locations tanks 1,5,3,2-4 stb&port,Q stb&port.


I am looking trough 360 panorama pictures and seeing tons of unidentified handwheels. I attached the screenshot, this one seems important due to its size. Very near to observation periscope. Do you know what it is for?


Also i realise that there is a good possibility that you may have already discussed this information with others to a great detail and with illustrative pictures. If this is so, and you still have these pictures which i cannot access due to forum crash then feel free to upload these again. I would love to take a look at them and learn as much as possible.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 06:51
Hi Tore,

I'm not seeing a picture for the oilcanning reply.

These responses are so awesome!  Thank you for telling us all about these u-boats!

I have another question:

On the Revell model, on the bottom of the saddle tanks there are two rows of 4 framed panels of some kind.  I am guessing they are drains of some kind for the saddle tanks.

I don't know if you know what these look like since they were usually underwater.  :)

Should they be grills or something?  I've seen some modelers make them as grills and others just leave them filled in as they come on the kit. 

Revell shows one grilled opening right next to them so if they were grilled I am surprised Revell did not mold in grill detail.  Perhaps they are copying U-995 in its restored state and maybe at Laboe they just covered the grills over.

Steve

(http://i.imgur.com/dNjhHt5.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 06:52
Hi Karel,

What game are you working on?  Is it the new multi-player one they are talking about over on subsim?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Sep , 2016, 07:42
I think he is working on completely different game for the Rift, at least that was what he showed me 2 years ago. (If he is the same Karel who contaceted me)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 16 Sep , 2016, 08:00
Hi Mark

Yes, that is me who contacted you years ago. Still hard at work and can really relate to you as i see how gigantic work this is to make a submarine game.

Hi Steve.
I am working on different game but since the guys who are making Marulken recently pivoted and started working on German U-boat then our game will probably have similarities and overlapping features.
Here is a year old article about hands on for our game vr demo. http://www.theriftarcade.com/hands-on-with-displacement-theory/ (http://www.theriftarcade.com/hands-on-with-displacement-theory/)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 08:15
Tore, could you explain how the light panel works and how its appearance change when in use?
The light panels serves two purposes the upper indicates by light and text if the most important hullvalves are open or shut. The lower panel is a report panel from the various compartments if they are ready for diving. I am not 100% sure which lamp refer to which compartment except engine room and conningtower.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 08:41
Hi Tore,

I'm not seeing a picture for the oilcanning reply.

These responses are so awesome!  Thank you for telling us all about these u-boats!


Steve.
The images you are showing are the kingstons on the saddle ballast tanks 2 and 4. The inlet with a grating is the kingston ( floodvalve ) for the Q tanks.
(untertriebzelle).See my image below and ask questions if any. For a model I believe it is probably correct to leave them open as can be seen on my model the should not have a grill.
Tore


I have another question:

On the Revell model, on the bottom of the saddle tanks there are two rows of 4 framed panels of some kind.  I am guessing they are drains of some kind for the saddle tanks.

I don't know if you know what these look like since they were usually underwater.  :)

Should they be grills or something?  I've seen some modelers make them as grills and others just leave them filled in as they come on the kit. 

Revell shows one grilled opening right next to them so if they were grilled I am surprised Revell did not mold in grill detail.  Perhaps they are copying U-995 in its restored state and maybe at Laboe they just covered the grills over.

Steve

(http://i.imgur.com/dNjhHt5.png)
Hi Tore,

I'm not seeing a picture for the oilcanning reply.

These responses are so awesome!  Thank you for telling us all about these u-boats!

I have another question:

On the Revell model, on the bottom of the saddle tanks there are two rows of 4 framed panels of some kind.  I am guessing they are drains of some kind for the saddle tanks.

I don't know if you know what these look like since they were usually underwater.  :)

Should they be grills or something?  I've seen some modelers make them as grills and others just leave them filled in as they come on the kit. 

Revell shows one grilled opening right next to them so if they were grilled I am surprised Revell did not mold in grill detail.  Perhaps they are copying U-995 in its restored state and maybe at Laboe they just covered the grills over.

Steve

(http://i.imgur.com/dNjhHt5.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 08:46
Steve
The photo of the U 995 May 1945 showing the hull without any significant canning is below I guess it has vanished on other posts
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 08:49
Hi Tore!

So the Kingston valves are basically big flaps, and on the ones on the saddle tank they open inwards, and on the bottom they open outwards?

So if they were closed, then the Revel kit should be fine as-is, I think.

That is great news - I saw one model builder's page where they had gone to great effort to make the Kingston openings on the saddle tanks have grills made from wire to look like the Q Inlet Valve. 

See about half-way down this page:  http://u-552.blogspot.com/2008_02_01_archive.html (http://u-552.blogspot.com/2008_02_01_archive.html)

 Glad I don't have to do that!

Karel:  Your video demo looks great!  I would love a Silent Hunter game with those kinds of graphics and interaction!

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 08:51
Hi Tore,

Thanks for the non-canning photo.

Sadly I have already followed many other modelers on my hull and completed this effect.  However I was already aware of your comments on it so I tried to go lightly.

You can see my build progress here:

http://www.shipmodels.info/mws_forum/viewtopic.php?f=28&t=163319

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 14:21
Karel.
The black valvewheel close to the navigation periscope belongs to the shut off valve of the schnorchel exhaustmast system.
When the schnorchelmast was installed they used the ballasttank exhaustblowing pipe as the schnorchel outletpipe. branching off directly before the exhaust blowing panel outside the pressurehull. The branch pipe goes up above the casingdeck following the towercasing and ends in the schnorchelmast shut off valve having a valvspindle down in the controlroom connecting to a black valvewheel as shown on your image. Again I have to use one of Simon Moriss excellent drawings to illustrate the system. The other smaller black wheel next to the periscope is the locking pin wheel for the schnorchel mast homing on the tower casing.
This pipe on the deck is often forgotten by the modelbuilders as it is not incorporated in the Revell kit
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 14:47
I think I have downloaded this "working drawing V05.pdf"  - can't remember the guy's username.

Ah, yes, it is Simon Morris' drawing.

But I only see a top view.

Is there a way to get a side view?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Sep , 2016, 14:57
Simons username is usually NZsnowman (his profession is snow & avalanches)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Sep , 2016, 15:04
Steve.
I believe the lower part of Simons image shows the side view, including the exhaust blowing panel valvewheels and the schnorchel shut off valve wheel in the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 21:23
Quote
Steve.
I believe the lower part of Simons image shows the side view, including the exhaust blowing panel valvewheels and the schnorchel shut off valve wheel in the controlroom.
Tore

Hi Tore,

Yes, I see that.  I am talking about his entire drawing of the uboat.  I have downloaded a PDF (version 5) of his drawings, but when you open it all I see is a top view.

From your picture, I gather there is also a side view.  I'm wondering how to access that - is it in the same PDF file or is it a different one?

Thanks,

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 16 Sep , 2016, 21:39
Hi Tore,

I have been looking at this picture and I have just realized from your version of it that what I thought was the snorkle head is actually the hydraulic cylinder; the snorkle is actually either raised or missing in this picture:

(http://i.imgur.com/HC7nQ62.jpg)

I have drawn a dotted outline where the snorkle would lie when lowered.

My question is:  The lateral braces that I have drawn arrows to - I assumed that these were the deck support struts/braces.

But there is no cutout for the snorkle!

So instead, are these braces below deck, running from the top of the port saddle tank to the top of the starboard saddle tank?

Are these braces what the snorkle lies on when lowered?

It is hard to see the perspective here. 

If I am seeing correctly, the casing is missing above the saddle tanks.  It appears to be cut off just behind the life raft cannisters.

So I think the braces we see from the life raft canisters forward are for the wooden deck, but the braces we see aft of there are below-deck.

But maybe this is just an illusion and I can't see the casing over the saddle tanks because it is being viewed edge-on.

But if the braces are for the deck, how does the snorkle get through them to lie down?

The more I look at it (follow the starboard side of the deck line) it looks like the casing over the tanks is in fact there.

So if all those horizontal braces are at deck-height, how does the snorkle lie down?

Thanks,

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Sep , 2016, 00:14
Steve.
I should not go into details of the image you are referring to as it shows the U 995 in Kiel during the first stage of the rebuild and to me it looks as if the girders and deck beams are of wood. The Germans ripped of the old original Schnorchel arrangement and installed a different type of schnorchel making a mock up of a raising cylinder etc. Below is a cross section view located at frame 55 about the area above COs cabin. I guess it gives a good impression of the casing sidesupports as well as the flood slit and knee plates between the casing side and saddle tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Sep , 2016, 01:25
Steve.
Simons drawings isa massive job which I guess would still take years to finish. I don`t think he has a complete sideview of a VIIC as yet. Below is an image, not complete, which I got so far.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 17 Sep , 2016, 12:06
Thanks, Tore, great stuff.  Thanks for the clarification on the snorkel. 

I have done mechanical design work for 20+ years, using 3D CAD software.  In fact I currently work for Solid Edge, a leading maker of CAD software.

Simon's drawings are fantastic, but it breaks my heart to see that much effort put into a 2D drawing when an actual 3D model could have been made instead.  :)

Imagine the potential!  Accurate computer game/simulation models.  The ability to 3D print actual scale components of a uboat for model making at any scale you desired.  The ability to make cross-sectional views at any desired point.

Perhaps some day another Simon will come along and do it in 3D.  :)

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 17 Sep , 2016, 12:45
Simon already works on the 3D model.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 17 Sep , 2016, 21:43
I'm glad Simon is working on a 3D version!

Tore:

I have updated my build progress here:
http://imgur.com/a/Z6K9m

I have laid in saddle tank extensions (which will be trimmed back greatly) and crafted a false pressure hull roof.  I did not go to the trouble to model the sharp ramp transition from the saddle tank down to the pressure hull.  I did not feel it worth the effort for the little view through the snorkel slot.

At the front of the Revell snorkel "box" there is another solid area where the head of the snorkel would rest.  I have also removed all of that so the entire opening gives a straight shot down to the saddle tanks/pressure hull.

Does this look acceptable?
(http://i.imgur.com/5inWBXZl.jpg) (http://i.imgur.com/5inWBXZ.jpg)
(http://i.imgur.com/9fzkrIYl.jpg) (http://i.imgur.com/9fzkrIY.jpg)
(http://i.imgur.com/fRBQtLNl.jpg) (http://i.imgur.com/fRBQtLN.jpg)
(http://i.imgur.com/7yZTdGBl.jpg) (http://i.imgur.com/7yZTdGB.jpg)

Thanks,
Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Sep , 2016, 23:57
Steve.
I guess your schnorchel recess is OK. There are of course limits how far you want to go as to the details using a commercial kit, the Revell kit is  not accurate in the details. For instance the anchorbay is, if not corrected on the newer kits, too far aft, the consequence would be the anchor is hitting the fore stb. hydroplane when lowered. I am afraid it is too late for a correction on your model. However the flood gates as we consider are the fingerprints of a VIIC can be corrected. The most significant would probably be the fore flood gates of the peaktank which on the real VIIC are asymetric as there are two on the stb. side and three on the port, not three on each side as on the kit. As for the ejector drains may be you should drill the holes in the aft end. Otherwise there are small deviations to various details depending on at which yard and year the Uboat was built.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 18 Sep , 2016, 11:06
Hi Tore,

Thanks for the comments!

Yes, there are many details that I have seen people do, like moving the anchor bay forward as you note.  Fairly significant surgery that requires re-adding rivets, etc.

I may plug the flood as you indicate on the starboard side, as that is pretty easy to do.

My intent with this kit is to build it fairly out-of-the-box (hah, famous last words).  I do not want to go too crazy with modifications and/or upgrades.  I burned out of model making 20 years ago when I kept raising the bar higher and higher to where I could never undertake anything because it was too overwhelming.

I'm probably going to display this as a "generic" VIIC/41 rather than label it as a specific uboat.  This gives me some "out" for inaccuracies.  :)

What do the ejectors eject?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Sep , 2016, 13:05
Steve.
I see your point of view but you are nevertheless deviating from the box with regards to the schnorchel casing recess, in that case I  would perhaps make the schnorchel lay- out correct as well, adding the missing deck exhaustbend and schnorchel shutoff valve both very visible on the stb front side of the tower casing, se my image below.
As to the ejector draining, there are very narrow free flood areas between the casing and the pressurehull, aft of MBT 5, marked blue on my image. When diving, a submarine should not leave a trail of bubbles on the surface thus you want to get rid of the trapped air in the void spaces as quick as possible. I guess the "blisters" on both side next to the difficult areas are creating an ejector suction effect to fill difficult the free flood area  with water when diving eliminating the bubble trails.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 18 Sep , 2016, 13:36
Quote
I see your point of view but you are nevertheless deviating from the box with regards to the schnorchel casing recess, in that case I  would perhaps make the schnorchel lay- out correct as well, adding the missing deck exhaustbend and schnorchel shutoff valve both very visible on the stb front side of the tower casing, se my image below.

Yes, having seen this snorkel detail from the Simon's drawings you posted, I think I am going to attempt to add it.  It does not look terribly difficult.

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 19 Sep , 2016, 07:08
Here is one fellow's work at moving the anchor well forward 7mm:

http://u-552.blogspot.com/2008/01/anchor-well.html

This is major surgery to the hull and would obliterate a lot of detail that would have to be added back in.  I'm going to live with the stock location. 

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Sep , 2016, 07:58
Steve. The correction wasn`t too bad, I did it on my model. Below is a photo I made during drydocking of KNM Kaura ex U-995 in 1954 when we "dropped the anchor" for inspection which illustrate the chain well clear of the stb. forward hydroplane guard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2016, 14:17
Hello Mr. Tore,


Here is what the bow section of my 1/32nd scale (about 7 feet in length) OTW U-96 looks like...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2016, 15:33
The U-96 tower is made from brass plate and brass rods - only the seats and and attack periscope shear are from resin.  It took over a week shaping the brass plate and using a butane torch to solder all the parts together.  The kit only included two flat brass tower sides and the two piece tower deck.  The rest of the parts had to be hand made by the builder (me)!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Sep , 2016, 23:32
Don.
Have you any idea how many hours you used building this model? It is huge what would the weight be?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Sep , 2016, 01:42
Hello Mr. Tore,


It took 2 years of every other weekend and 2 years of my 5 weeks of vacation.  I figure about 1,400 hours and I will attach some building photos...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Sep , 2016, 01:54
again
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Sep , 2016, 01:58
The last photo shows the brass nuts holding the brass forward hydroplane to the hull.  Originally the fairings has only studs.  I threaded the studs and bolted the fairings into place and then covered the nuts with fiberglass resin to perminately seal everything into place..
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Sep , 2016, 03:46
Don. You are a true U boat enthusiast having the stamina to spend almost every week end and vacation on a model project for two years.
 Seeing the shiny brass propellers reminds me of the VIIC propellers which I guess up 1942 were of a propeller brass alloy, afterwards  the VIIC propellers were made of a special steel. Submarine propellers are a special science, the VIIC propellers were not of a particular advanced design, they were susceptible to cavitation on the tip of the blades as well as towards the boss. The pittings were bad, but cavitation is noisy due to the implosions of the vapour bubbles.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Sep , 2016, 20:15
Hello Mr. Tore,


Several years before building U-96, I built a Me 109 Messerschmitt (48 inch wing span - 5 weeks to build) and a Focke Wulf 190A (54 inch wingspan - 6 weeks to build).  Both aircraft are made from pieces of white aspen wood (no knots) and not a kit; just weeks of sanding (scratch built)...


I was very interested in aircraft form my teen-age years until 2003; when I got interested in U-Boats. A Long time ago, I had a private pilot license and taught aeronautics to high school kids at the Civil Air Patrol when I was a college student. Going to work for the NCR Corporation and computers changed all that because I had to support a family.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 21 Sep , 2016, 02:41
The other smaller black wheel next to the periscope is the locking pin wheel for the schnorchel mast homing on the tower casing.



Tore. The other black wheel that you mentioned. I tried to locate it on panoramic pictures. I found bunch of black wheels near the periscope. Can you identify their purpose? Are they all tied to schnorchel mast control system?


Many thanks.
Karel
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Sep , 2016, 09:12
Karel.
Identification control room valves. Below is an image which I guess should be the relevant valves.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Sep , 2016, 09:20
Hi Karel,


In addition - These are the images that Mr. Tore provided to me a while back.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 21 Sep , 2016, 20:24
I have used a detailed Type VIIC schematic on the web to show what the keel looks like behind the bottom floods at the bow of the boat:

(http://i.imgur.com/YV8tAl9.png)

I used this to make a template to make a matching piece to put into the hull of my model.

I am looking for something similar for the stern floods.

Does anyone have a suitable picture?

Thanks,

Steve

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Sep , 2016, 01:10
Steve.
I don`t think the VIIC has much of a keel in the aft end, the keel begin at about frame 14. Aft of that a double skin hull takes over before it gradually is transferred into a skeg. May be my images below gives an indication. A detail which seems to be forgotten by everybody is the zinc anodes which are protecting the area from galvanic corrosion. You might see the steel fixing straps on the A brackets. The zinc anodes were only plates of zinc app. 20x35 cm 20-30 mm thick fixed to the propeller A brackets as sacrificing elements for the galvanic corrosion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 22 Sep , 2016, 11:36
Ah-ha, but your blueprint does show the frame/baffle with holes in it above the skeg.

The schematic I was looking at does not show it:

http://files.balancer.ru/forums/attaches/2013/03/31-3107743-planstypeviic.jpg

But yours does - do you have a larger version of your schematic?

Thanks,

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 22 Sep , 2016, 11:42
This is the piece I need to create:

(http://i.imgur.com/0RSFePp.png)

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Sep , 2016, 14:29
Steve.
May be one of Simons excellent drawings would clarify the matter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 22 Sep , 2016, 17:35
Hi Tore,

Unfortunately, Simon's drawing does not show the central keel baffle that is in your schematic above.

You can see where I highlighted it here:

(http://i.imgur.com/0RSFePp.png)

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Sep , 2016, 22:02
Will this help?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Sep , 2016, 01:29
Steve.
I guess I finally understand your question. I don`t think it is  an alongship bulkhead in the skeg, only atwartship frames and skin. What you see on my crossection drawing is an indication for a doubler in the way where you have support for the propellers-, rudders- and hydroplanes- guards. I guess Simon has indicated the doublers very well on his drawing.
Further you`ll see the crank for the aft hydroplanes operation is fitted in the center of the skeg.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 23 Sep , 2016, 06:08
Hi All,

What I am trying to do is make the section of the keel that is behind the lower floods, fore and aft.  I have achieved the forward ones.

This is the effect I am trying to duplicate, from another modeler:

(http://4.bp.blogspot.com/_AQZRtRcYS54/R6O6AG2-uZI/AAAAAAAAAR0/aDkADw21zzg/s1600/ribs+002.jpg)

In Tore's earlier post he showed this picture:

(http://i.imgur.com/lsYDDqh.png)

In this image, on the aft end of the pressure hull, both above and below you can see a frame with flood holes in it, presumably along the centerline of the hull.

I have highlighted it in this close-up of the same image here:

(http://i.imgur.com/0RSFePp.png)

The purpose of this detail on the model is simply to make it so you don't see straight through the floods from one side of the ship out through the other side without seeing a mock-up of the internal structure of the ship.

All subsequent schematics posted do not show this detail. 

Perhaps it is not really there?

I believe at this point I will simply fake something in; the detail is not actually important as no one will be able to directly see it.

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Sep , 2016, 06:40
Steve.
You are not the first one who makes effort in preventing that you should not "see through the free flood gates. For some reason there are aversions to this possibility. The fact is you are able to "see trough" on the real VIICs as there are no center bulkheads, so why make up something which are not there in real life? You should never copy the details on the museum U 995, but in this particular case you may, see my images of the area below, on one of the original photos you are actually able to see through the freeflood area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Sep , 2016, 07:37
Steve.
My image showing a longitudenal cross section of the stern is probably not a very good one as the doubler is drawn as a square box which might be mistaken as a floodhole. However Simons drawing is correct and he has drawn the doublers as they looks. A doubler is an additional steelplate riveted in places to increase the strength locally, in these cases to support the propeller-,hydroplane- and rudder guards connection to the hull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 23 Sep , 2016, 08:34
Hi Tore,

The issue is not being able to see through the floods, but to see through unobstructed.  There should be something seen partially blocking the view if you look through the floods.

However, looking again at your picture, the piece that is missing from Simon's drawing may be above the floods anyway.

(http://i.imgur.com/fWjV5CQ.png)

Though it is not clear to me what this framing structure would rest on if it does not go all the way to the keel.  It would be like a "fin" welded to the aft end of the pressure hull attached to...what?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Sep , 2016, 11:54
Hi Steve,


I believe you are looking at stringers with holes (baffles) which are internal to MBT 1. So I believe Simon's drawing is correct (but doesn't show the lower internal stringer) and Mr. Tore pointed out the heavy metal strip which the post was attached.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 23 Sep , 2016, 12:12
Oh, I think I see what is going on here now.

These stringers are not on the vertical cross section of the hull.

It looks like they are at an angle. 

So instead of going straight down from the pressure hull to the keel, they go radially out from the pressure hull to, it seems, the outer hull, intersecting just above the floods.

I think this is the correct interpretation?

(http://i.imgur.com/aT6zaRj.png)

So there appears to be nothing in between the floods looking straight across the hull.  So the previous modeler's interpretation was incorrect.

Thanks,

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Sep , 2016, 08:44
Steve.
May be my image below illustrates how the double skin hull is attached to the pressurehull, the image is of a IXC but the system is the same as on the VIICs.
I don`t think there are any floodholes in the skeg.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 25 Sep , 2016, 14:31
Hi Tore,


regarding the discussion about type IXC buoyancy tanks in the next thread, I would like to ask you, how these tanks were used on KMN Kaura? Did you cruise at surface with tanks flooded or blown? Or depended it from the sea state?
If flooded, with vents permanently opened?




--
Thanks, regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Sep , 2016, 21:53
Hi Steve,


In my humble opinion - I think the skeg keel has a heavy metal lower base where the metal vertical rudder protection structure is attached besides the hydroplane drive shaft and the dual prop support.  The skeg keel only has internal vertical frames and flooding holes on each side.  There are no stringers internal to the skeg keel...  It looks to me that Stringer #1 is only internal to MBT 1 and attached to the aft pressure hull.


The 1st image Stringers 1 shows stringer #1 and it looks to be at an angle (possibly several stringer #1's).  The 2nd image MBT 1 shows a vertical slice of the U-Boat at frame +2 and the stringers are all internal to MBT 1, and at frame -6 there are no stringers visible.


I hope this helps,


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Sep , 2016, 23:44
Maciek.
The buoyancy tanks did not participate in the surfacing procedure as they are primarily used to improve surface buoyancy to prevent ( bow tank) undercutting. To a certain extent there are selfdraining (more timeconsuming than blowing) as the tank is situated above the surface.   When pitching I guess the waterlevel in the tanks pulsated thus compressing the air in the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 26 Sep , 2016, 07:49
Quote
In my humble opinion - I think the skeg keel has a heavy metal lower base where the metal vertical rudder protection structure is attached besides the hydroplane drive shaft and the dual prop support.  The skeg keel only has internal vertical frames and flooding holes on each side.  There are no stringers internal to the skeg keel...  It looks to me that Stringer #1 is only internal to MBT 1 and attached to the aft pressure hull.


The 1st image Stringers 1 shows stringer #1 and it looks to be at an angle (possibly several stringer #1's).  The 2nd image MBT 1 shows a vertical slice of the U-Boat at frame +2 and the stringers are all internal to MBT 1, and at frame -6 there are no stringers visible.

Hi Don,

Yes, the images you have posted are quite helpful.

Stringer #1 is what I was after.

From the images you have posted, I believe that Stringer #1 does not lie on the centerline of the boat.  It probably radiates away from the pressure hull to the outer hull at angles, probably roughly in-line with the prop shaft supports, as I had previously guessed and illustrated here:

(http://i.imgur.com/aT6zaRj.png)

I think thiis is corroborated by your image:

(http://i.imgur.com/2eE86g1.png)

So the stringer #1 that I thought I was seeing in vertical section as lying on the section plane is actually placed radially out from the pressure hull.

This means that the skeg is hollow and there seems to be nothing in between the floods on one side of the boat to the other.

The modeler I was following on the U552 blogspot site was incorrect.

I think I understand now. 

Steve



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 26 Sep , 2016, 10:08
From another thread:

Quote
Hydroplanes.
The forward hydroplanes have no connection to the outer part of the hydroplaneguards. On many drawings it looks indeed as if there is a throughgoing shaft ending up in the hydroplane guard, however the hydroplane shaft end up in a fixing point about half way into the hydroplane, I guess you`ll find a bolted accesshatch at the fixingpoint.
The aft hydroplanes are slightly different although the shaft and fixingpoint are the same there is a small connection to the guard at the outerpoint. As far as I remember it is not a support shaft and bearing at the point rather a small bar shutting the gap to prevent ropes or other objects to enter the propellerarea.
The jumping wire on the fwd hydroplane guard was removed sometimes I guess at the time when the netcutters were removed. This reminds me of an event we had near Scapa Flow when we anchored waiting for orders over the night. In the morning raising the anchor we experienced the anchorcable was stuck between the forward hydroplaneguard and the hydroplane. We had to free dive  in the cold November sea (wearing longjohns) to release the cable.

So, I gather that the guard on the front hydroplanes should not physically attach to the hydroplane itself?

Also, the guy wire running from the hydroplane guard to the hull was ommitted about the time the net cutters were removed?

I have a question about the radar.  Did it emit harmful radiation to the watch crew?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Sep , 2016, 11:30
Steve.
Below are the images of the fore hydroplane as you see no connection with the guard, contrary to the aft having a nut. Yes I guess they did away with the wires around end 1942.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Sep , 2016, 11:39
We did not use the radar very much as it wasn`t any good. To my knowledge nobody was hurt by radiation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 26 Sep , 2016, 12:26
Quote
We did not use the radar very much as it wasn`t any good. To my knowledge nobody was hurt by radiation.

But the watch crews had uncanny eyesight after their third eyes grew in!  :)

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Sep , 2016, 13:54
Hi Steve,


I believe you've got it... The one thing I had a hard time understanding at first was MBT 1 (AFT) and MBT 5 (fwd) were designed very similar to the saddle tanks (MBT 2 and MBT 4) and all being exterior to the pressure hull.  Where the U-Boat's outer sheet metal casing is the ballast tank's exterior. In the lower drawing, the frame that makes a full loop is inside the interior of MBT 1, and the U-Boat's sheet metal outer skin/casing is the exterior of MBT 1. When I first started studying the Type VII C U-Boat, I had in mind that MBT 1 and MBT 5 were ballast tanks inside the exterior hull casing. The only tank that is different is MBT 3 where this tank is inside the pressure hull under the control room floor. However, the lower portion of MBT 3 is the pressure hull which is the under belly of the U-Boat's exterior mid-section.


If I have made any incorrect statements, then I sure hope Mr. Tore or Maciek will jump in and correct me on this subject because I'm still learning from these gentlemen!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Sep , 2016, 23:27
Don.
No need to jump in. The lower aft part of the skeg has space for the the pull/push rod, crank and fulcrum shaft bearings for the aft hydroplanes operation being able to move 30 degrees up and down.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Sep , 2016, 04:29
Studying the many photos of the aft part of the skeg I guess it is possible that this is cast steel riveted to the outer hull by a double row of rivets. The casting incorporate the support for the aft hydroplanes fulcrum shaft as can be seen on the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Sep , 2016, 18:08
Hello Mr. Tore,


When you surface a U-Boat one diesel is used to power the U-boat on the surface...  I guess the 2nd diesel is used 1st to exhaust blow the ballast tanks, and then charge the batteries. Is it possible to do both at the same time with the 2nd diesel?


Regards.
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Sep , 2016, 00:29
Don.
The possibility exsist, adjusting the charging load, I would probably prefer to put the charging on the propulsion engine shaft. When blowing the ballastanks by diesel exhaust the ruling factors are the bmep ( break mean effective pressure)and exhaust backpressure as one diesel is producing ample volum for blowing the tanks. The total exhaust backpressure is constantly monitored by an engineer in the engineroom keeping an eye on the exhaustmanometer and adjusting the pressure by the outer group exhaustvave  designed for the purpose. The bmep is monitored by an engineer at the engine maneuvring stand. The distribution and pressures for the induvidual tanks are monitored by the controlroom engineer at the exhaust control panel. If for some reason the pressure becomes too high there is a reliefvalve on the engine exhaustmanifold which release the exhaust into the engineroom. I have experienced that a few times and it is very unpleasant.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 04 Oct , 2016, 10:24
Tore


Do you if there is any source online where i could locate the lighting of the boat? I am looking trough museum panoramic  pictures and am able to see lightbulbs but they seem to be too few in numbers. They have been probably removed. I would like to keep my lightbulbs more or less at the same places where they were originally.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2016, 00:39
Karel.
Unfortunately I have no cabling plan or images of all the original accommodation lamps/bulbs of the U-995. My best advice would be to look at the various images particularly the kubische panorama.de of the U 995 at Laboe. The museum boat has of course different lights and modern cabling racks as can be seen on my image below. The orgininal fittings are shown as well. Note the lightbulbs had a thick glassprotection as shown.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Oct , 2016, 01:18

Karel.
Following up your VIIC lampquestions. A few lamps had lampshades, like in the wardroom, CPTO mess and PO mess.The Bavarian Filmstudioes made a good research on the lamps, shades and colours for the execellent movie das Boot. Below is an image showing the various lamps.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 10 Oct , 2016, 11:52
In 'Das Boot' during the Alarm they the crew is shown running forward and swatting a hanging light/shade out of the way.  I was amazed that it could tolerate that without blowing the bulb or damaging the cable.

Realistic?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Oct , 2016, 14:12
Steve.
Battlestations or divingstations as we called it, would generally imply mostly people moving from forward compartment to aft. This would mean the officer on watch would give the order to the trim man prior to the divingstation order:" pump 400 liters from aft to fore". When you heard that order you would  anticipate the next order:" divingstation". In the CPTOs mess and the wardroom you usually could hear pretty much of the orders given in the controlroom and the lamps in the CPTO,and PTO messes were usually moved to the side, in the wardroom the passageway was on the stb side leaving the lamp hanging over the table undisturbed. When the order was given, contrary to the Movie, the rush of people was not as noisy and dramatic. But of course the movie people wanted to have some drama.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 11 Oct , 2016, 13:18
Quote
Battlestations or divingstations as we called it, would generally imply mostly people moving from forward compartment to aft.

Hi Tore,

I assume you mean people moving from aft compartment to forward?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Oct , 2016, 14:39
Hello Mr. Tore,


I'm having an issue about (rethinking) how to describe the ballast tanks...


In the type VII U-Boat the forward, center, and aft tanks are described as Tauchzelle or diving cells, and the saddle tanks are described as Tauchbunkers or diving bunkers.


Diving cells are strictly water ballast tanks, and diving bunkers are configurable to a reserve fuel oil (RFO) or a water ballast.


When did these tanks become Main Ballast Tanks and labeled MBT 1, MBT 2, MBT 3, MBT 4, and MBT 5? Was this done in translation to eliminate the confusion between the Gerrman diving cells and diving bunkers?


Which is correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2016, 00:04
Steve.
The largest accommodation for the crew was the fore torpedoroom having 12 fixed bunks as well as hammocks,  the majority of these people had their divingstations aft of the accommodation. The officers and CPTOs had their divingstations aft of their accommodations as well and even most of the PTOs, engineers and electricians had to move aft , to the engineroom and E room, hence the the trim of the boat had to be compensated by a larger trimming moment pumping 400 liters from aft to fwd. trimtank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2016, 01:09
Don
I Guess the RN English nomination derives from the translation done by the RN when they got hold of the VIIC documents during WW2. I am pretty sure the Germans used the expressions mentioned on the original GA drawings. The problem could be that the various tanks were used to a certain extent differently by the German Navy and RN. F. inst the Untertriebzelle in RN English we used the nomination Q tank for quick diving whenever you had to change depth quickly (e.g. not dynamically) as f. inst. in the case you had to avoid ramming. The German used the Untertriebzelle to assist a quick diving from the surface ( to overcome the "surface resistance") and got the name for that purpose, Unter ( under) trieb (force) zelle. The Germans did the numbering for frames, tanks, dieselengine cylinders etc starting from aft we did the opposite. The Germans were not consistant though, as the fore torpedotubes have the nos 1 & 3, 2 & 4 and the aft no 5. It is hard to state what`s correct I Guess describing a german piece of engineering would be using the German system, for a non german speaking english person it might give a better understanding using the RN English. But I really have no idea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Oct , 2016, 00:03
Hello Mr. Tore,


During a submerged torpedo attack, how many people would be in the tower?


I count three (3)
- the captain
- the helmsman
- and someone to input the TDC data?


Or was that a 2nd job for the helmsman?


Regards,
Don_


P.S. I have until December 1, 2016, to make any changes to Skizzenbuch according to my managing editor.  I should be finished in about two weeks with the clean-up and changes and will upload it to dropbox.  I believe I should use FBT 2 and 4 instead of MBT 2 and 4 because of the different German wording - Tauchbunker Vs Tauchzellen.  The US and British reports on different U-Boats use the FTB term for the RFO or Ballast Tanks...


If you have any suggestions, then please let me know???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2016, 00:42
Don.
I assume you are referring to submerged launching of torpedoes at periscope depth. We usually had two men in the tower and kept the helmsman in the controlroom. However our CO preferred to carry out most attacks (simulated) from the controlroom as can be seen from the image below.
I guess it is a good idea to change the saddleballasttanks to FBT instead of MBT.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Oct , 2016, 11:20
Hello Mr. Tore,


If it were a submerged torpedo attack and the CO was using the attach periscope in the tower, then there would be another person involved in the operation; a helmsman, the CO, and who would the person be handling the TDC? Who would normally input the info into the TDC on any type of torpedo attach scenario? I thought the No. 1 Officer handled a torpedo attach from the bridge using the UZO... Could they all fit into the cramped tower space, or would the helmsman need to take his station back in the control room?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2016, 11:33
Don.
I don`t remember 100%, but I Guess the helmsman would be in the controlroom. We very seldom had the helmsan in the tower. He was generally either on the bridge during surface harbourmaneuvre or in the control room.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Oct , 2016, 12:13
Tore, can you remember how the wooden deck hatches were fixed to the deck so they would not float away?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Oct , 2016, 13:49
Simon.
All the wooden hatches had hinges and were locked in place, a typical example is the hatch adjacent to the hydraulic cylinder of the schnorchelmast seen on the images below.( U 968). For the wooden deckhatches connected to the pressurehull hatches was a special arrangement whereby you opened the wooden deckhatch simultaneously with the pressurehull hatch by a system of hingerods as can be seen on the image. Note the wooden deckplanks were bolted to the steel supports shown on the image. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2016, 02:41
Simon.
All the wooden hatches had hinges and were locked in place, a typical example is the hatch adjacent to the hydraulic cylinder of the schnorchelmast seen on the images below.( U 968). For the wooden deckhatches connected to the pressurehull hatches was a special arrangement whereby you opened the wooden deckhatch simultaneously with the pressurehull hatch by a system of hingerods as can be seen on the image. Note the wooden deckplanks were bolted to the steel supports shown on the image.

(https://c6.staticflickr.com/6/5807/30484303765_bc862f6937_o.jpg)
This images has been resized. Click to view original image.

(https://c1.staticflickr.com/6/5685/30367422072_638fbfd5d7_o.jpg)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Oct , 2016, 06:04
Simon.
I can`t remember the exact details, but below is an image of KNM Kaura 1953 showing some details of the wooden casingdeck hatches may be i can be of some help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Oct , 2016, 11:12

Hi Don,


If it were a submerged torpedo attack and the CO was using the attach periscope in the tower, then there would be another person involved in the operation; a helmsman, the CO, and who would the person be handling the TDC? Who would normally input the info into the TDC on any type of torpedo attach scenario? I thought the No. 1 Officer handled a torpedo attach from the bridge using the UZO... Could they all fit into the cramped tower space, or would the helmsman need to take his station back in the control room?


During submerged attack, the TDC was operated by (Ober)Bootsmann, CO was at the attack periscope. There was space for three men in the conning tower. Between helmsman saddle and attack periscope was hatch to the control room and ladder to the bridge. The TDC operator was on the most inconvinient position.


As you said, IWO was at the UZO sight column duiring surface attack and in the control room when submerged.


--
Regard
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2016, 12:33
Simon.
I can`t remember the exact details, but below is an image of KNM Kaura 1953 showing some details of the wooden casingdeck hatches may be i can be of some help.
Tore

There seen to be a huge variation in deck hatches layout between the boats. I will use the normal layout for U-1308.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Oct , 2016, 00:11
Hi Maciek


Damaged Armature and the use of Field Sw-I and Field Sw-II


Skizzenbuck page 398


Would this be accurate?


"The motor on the left is disabled mechanically by uncoupling the direction switch control with field switch I (off position). Two switch commons will be in an open position, while a resistor is used to discharge the shunt windings from MI by a third set of contacts (upper). With this failed condition, the motor on the right MII may only be run in the parallel configuration.  However, the thing to remember is both e-motor armatures are housed in the one motor casing and pinned to the same armature drive shaft; one armature is powering the common drive shaft while the damaged armature is free spinning.


Do you know if the direction switch had to be in off position in order to uncouple MI or MII with field switch I or field switch II when an armature was damaged.


The older switchboard they could uncouple the switch blade actuators in any position.  However, I'm not sure what they had to do to the wiring for the armature induced current in the shunt windings???


Regards,
Don_


PS - I personally went into the Comcast email and disabled their spam filter, so my Comcast e-mail account should pass any email to my home MS Outlook e-mail account on my system.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 Nov , 2016, 13:23

Hi Don,

Would this be accurate?


"The motor on the left is disabled mechanically by uncoupling the direction switch control with field switch I (off position). Two switch commons will be in an open position, while a resistor is used to discharge the shunt windings from MI by a third set of contacts (upper). With this failed condition, the motor on the right MII may only be run in the parallel configuration.  However, the thing to remember is both e-motor armatures are housed in the one motor casing and pinned to the same armature drive shaft; one armature is powering the common drive shaft while the damaged armature is free spinning.

It is ok and accurate. I only wonder if phrase "disabled mechanically" does not suggest that the half of the double-armature motor is mechanically locked.


Do you know if the direction switch had to be in off position in order to uncouple MI or MII with field switch I or field switch II when an armature was damaged.

Well, I'm sure that direction switch should be in off position. However I do not know if direction switch is interlocked somehow with field switches or it is the operator responsibility to switch them while in correct positions.

I rather think that Germans interlocked them in such way that the field switch could be toggled only when direction switch is off. In other case, it could be fatal, when while running both armatures, the field switch was toggled accidentally.


The older switchboard they could uncouple the switch blade actuators in any position.  However, I'm not sure what they had to do to the wiring for the armature induced current in the shunt windings???

I have to think about this.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Nov , 2016, 14:27
Hello Mr. Tore and Maciek,


Thank you for the info about the Field Switches...  I have been working on a re-write of several sections of Skizzenbuch (text, photos and drawings), and I still need to verify the text on my 3rd section (I'm about 70% done); there are 5 Word/PDF sections to Skizzenbuch.  However, I have re-compiled the DPF files into one document and uploaded what will be presented to my managing editor on December 1st to dropbox. Possibly one more re-compile before Dec 1, if any of the text in section 3 needs to be changed, or if I get any suggestions form you all.  I think this process has improved the final product and I took Jak Showell's suggestion and verified all the German text and found several spelling errors on my part.


The latest version "Skizzenbuch 11 x 17 - M + Index.pdf" is available in dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Nov , 2016, 02:32

Hi Don,

The older switchboard they could uncouple the switch blade actuators in any position.  However, I'm not sure what they had to do to the wiring for the armature induced current in the shunt windings???

I have been analyzing the schematic of the lever switchboard and in my opinion, the Feldschalters in this older type of switchboard do not have the same function as in the rotary type switchboard (i.e. disconnecting field winding while respective armature is damaged).

When I gather my comments and make some sketches, I will post them here.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2016, 07:13

Don.
I have started to look through your latest Skizzenbuch and have some comments to your page 28 plate 6. You have added the english text for the icon of a sea boardvalve as used in the translation from german to english. I guess this might be a bit general for an important valve. The valve a is the main seaboard inletvalve for the trim/regulating and evaporator systems having the standard LPairconnection for seaweed blowing and a branch of to the evaporator valve, a 1, as well as a connection to the finefilling valve, a 1, for the regulating- and trimtanks as can be seen on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Nov , 2016, 15:18
Hello Maciek,


Page 380 - there looks to be a lock-slide between the Sw1 and Sw2 Direction Switch Assembly. Also, I have attached a photo of the Type IX switch panel where this is visiable...


Mr. Tore, I need time to look at your comments...


I completed the review of section 3 and re-complied and uploaded the latest to dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 02 Nov , 2016, 16:36

Hi Don

Page 380 - there looks to be a lock-slide between the Sw1 and Sw2 Direction Switch Assembly. Also, I have attached a photo of the Type IX switch panel where this is visiable

Could you please mark this lock-slide on both drawings? (you can send them to me by email)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Nov , 2016, 20:55
Hello Mr. Tore,


I added the info you provided on page 31...  Re-compiled the book and placed the updated version in dropbox.


Thank you,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Nov , 2016, 01:57

Hi Don,

ok, now I know what you mean. Yes, this lock-slide was used to couple direction switches of each armature together, so when the E-Motor was klar, both armatures were powered in the same way. When one armature was damaged, the lock-slide was removed, respective switch was set in the Aus (middle) position, and the other switch could be operated independently.

However, this lock-slide was not coupled with Feldschalters, and I think that these Feldschalters were used during normal operation (not in case of damaged armature). I will post more details soon.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2016, 03:00
Don.
Checked page 31 OK. Page 38 plan7. Your text on plan 7 dealing with the use of Q is a bit unclear and as you have a full description of the use on the following pages it might be an idea to ommit same and give a general description of the Q, may be something like this: The negativ buoyancy tanks stb. and port are located outside the pressurehull in the saddletanks, they are provided to reduce the divingtime. The tanks are pressureproof. Each tank is flooded by a floodvalve operated from the control room. The tanks are vented inside the boat through a common muffler and blown by HP air from the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Nov , 2016, 13:55
Hello Mr. Tore,


I made the changes to page 39, page 38 has the discussion about the Manual No. 381 (Tauchvorschrift).  I also corrected a spacing problem on page 52  -  4.700m3 to 4.700 m3 - Note, I didn't use the sup option to raise the 3 (cubic) because I can't seem to get out of that option when once in...


I uploaded the updated Skizzenbuch into dropbox...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Nov , 2016, 22:39
Hello Mr. Tore and Maciek,


Maciek, I took all your suggestions with reference to the G7e torpedo heating and charging, and the info you provided about the Switchboards...


Pages - Torpedoes
283 - added text
284 added graphic and text
312 - worked on text
314 0 added a paragraph


Pages - Switchboards
Page 378 - changed item (e) Starting Contactor, and (f) Motor Circuit Breaker
Page 379 - corrected labels on drawing
Page 380 - corrected drawing, added a photo and text
Page 381 - corrected drawing added text
Page 390 - Corrected drawing added Starting Contactor and item 1
Page 391 - corrected item 1


I have a question about the photo on page 396 - the items on top of the e-motors are described as converters.  However, they do look different.  Is the description accurate?


I uploaded the latest version of Skizzenbuch with all of these changes into dropbox. I sure hope I haven't made a mess of things...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Nov , 2016, 02:35
Page 380 is wrong!!!  I will re-post a update to Skizzenbuch tomorrow...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Nov , 2016, 03:32

Hi Don,

I have a question about the photo on page 396 - the items on top of the e-motors are described as converters.  However, they do look different.  Is the description accurate?

Yes, it's accurate. They look different because they are different type. The converters differs one from another due to different output voltage, frequency (i.e. rotary speed), output power, number of generator windings. All these things cause that the look different.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Nov , 2016, 15:52
Hello Mr. Tore and Maciek,


Maciek, thank you for the info about the photo of the E-Motors...


I have uploaded Skizzenbuch to dropbox with the fixes to page 380 and hopefully my confusion about un-coupling the speed controller hand wheels is now correct for the Type VII C U-Boat...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Nov , 2016, 18:31
(https://c3.staticflickr.com/6/5712/30170937554_cf442aa47d_o.jpg)
Plate 16: Flooding, venting, low pressure exhaust gas and emergency blowing systems http://www.uboatarchive.net/U-570/U-570Plate16.htm (http://www.uboatarchive.net/U-570/U-570Plate16.htm)

Hi Tore

I have a few questions:

Valve C - Emergency vent (flap) valve
Valve M - Drain valves
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Nov , 2016, 01:21
Hi Simon,


Here is what I have...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2016, 01:39
Hi Simon,


Here is what I have...


Regards,
Don_

Thanks Don.

Do you know if the Valve M - Drain valves, drain into the open ocean?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2016, 03:27

Simon.
As you know there are extensive ventducts under the casingdeck and for the saddletanks you have even gatevalves in the ducts to be shut from outside the pressurehull when in fuelconfiguration. As the saddletanks venting ducts are interconnected in a stb and port system they are susceptible to damages like shrapnels, machinegunfire etc. If the ducts are damaged you are in fact damaging port or/and stb saddle ballasttanks, hence you have an emergency shutoff valve at the ventduct entrance to the tanks. The emergecy shut off valves are operated inside the pressurehull but as the handlewheels are usually removed they are hard to see. The double line on the plate is indeed indicating the pressurehull.
On some photos you might be able to see the valvespindle and the traditional valveindicator right above the chart table on the fwd. port side of the controlroom,as on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2016, 03:37
Simon.
The drains m are situated in the ventingducts for the saddle ballasttanks under the casingdeck and has nothing to do with the RFO tk.1 or neg boyancy tanks.The drains are operated from outside the pressure hull to the sea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Nov , 2016, 05:56
Simon.
The drains m are situated in the ventingducts for the saddle ballasttanks under the casingdeck and has nothing to do with the RFO tk.1 or neg boyancy tanks.The drains are operated from outside the pressure hull to the sea.
Tore

What diameter do you think the drain would be?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2016, 06:58
Simon.
I guess you found the diameter of the exhaust silencer drains previously and that diameter would probably match the vent duct drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 22 Nov , 2016, 08:15
Hi guys. Been super busy trying to get the multiplayer to work. Good news is that everything seems to be syncing correctly. I can pull levers and dials and information gets transferred trough the network to another player.


So i have been trying to figure out how the speed command system worked on u-boat.  I see that there is engine order telegraph in command room and there is engine order receiver in motor room.
If i had to guess then someone from command room dials in the command and it gets copied to the engine room telegraph? Then this information is used to adjust the motor speed manually by machinist?
But i also see a hand lever on order telegraph that is in the diesel room and i am not sure what is the reason. How did this all work exactly?


Many thanks.
Karel
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2016, 10:44

Karel.
The engine telegraph system consist of the order telegraphs, e.g. the telegraphs setting the orders. You have two sets (port and stb) of telegraphs one set in the conningtower and one set in the control room transmitting the COs or officer of watchs order to the dieselengineroom or e-motor room.
The orders given can be both direction of propellerrevs and the speed. For the dieselengines on the VIICs built after 1942 there was no reversing hence the dieselengine telegraphs could only order ahead revs and speed. As can be seen on the image below the telegraph could order increase of revs by 10, diesel engine operation  or e-motor operation as well as batterycharging. Maneuvring of uboats delivered later 1942, like alongside the jetty, you  used solely the E-motors.
When the engine order is given by the CO or officer of the watch, the helmsman put the orderlever in the ordered position which is transmitted to the diesel engine- or E-room. Prior to the execution of the order the engineer answeres, acknowledges, the order by putting the lever in the same position as the orderlever and adjust the engine. Likewise in the E- room where the electricians carry out the order in the same way.
When an order is given, a sound is made and a red light is flashing only to be stopped when the oder is acknowledged by the engine telegraphhandle.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 22 Nov , 2016, 11:16
Thank you.


Just to make sure if i get this correctly on how the information is switched between telegraphs.


When i give an order from command room and put the handle on full forward, when will the needle on my telegraph move to the forward position? Will it move only after the machinist has acknowledged the order by moving his handle?


So when i move handle on my telegraph the needle moves on diesel room telegraph. Machinist then acknowledges that order by moving his telegraph handle to the needle position.  And by doing so he activates the needle movement in the command room. This way the CO will get confirmation that the order has been carried on.  Is this right?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2016, 11:38
Karel.
I Guess you got it. When you put the telegraph handle in the control room  to full ahead, the pointer on the engineroom telegraph moves to full ahead and the alarm is sounding and red ligth is flashing. When the acknowledgement handle on the engineroom telegraph is overlapping the new order pointer position, the flashing light and the audioalarm stops and the engineer is executing the order. In the controlroom the enginetelegraph aknowledgementpointer is moved simultaneously to match the orderhandle signalling the correct understanding and the audio alarm stops.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 22 Nov , 2016, 12:41
That is wonderful :) I am coding this behaviour into my game.


And thank you again so much. Not just for this, but for all the information that you have given in this thread over the years. Discovering this knowledge source has made my job so much easier. I really appreciate it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2016, 10:09
Hello Mr. Tore and All,


Today is Thanksgiving here in the USA and I have a lot to be thankful for this year... I am very grateful for all the new friendships that I have made on this website. This past year, I went to Schiffer Publishing in Atglen, Pennsylvania, who will publish "Skizzenbuch" this Spring 2017.  This book would not have been possible without the help from all of you.  Mr Tore, without your knowledge and experiences, Skizzenbuch would have been just another book of facts and drawings about U-Boats.  Your personal life experiences added the "Special Effects" to the book and will make a huge difference for the reader. As I said before, I have a lot to be thankful for this year...


Kind regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2016, 12:02
Don.
Thank you for the kind words and greetings which I Return by sending you my card from my farm in the deep forrests of Norway. I wish you all the luck with your Skizzenbuch and judging from the many questions put forward on this thread I guess there is a marked. Looking forward to seeing the final result.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 30 Nov , 2016, 20:15
Hello again Tore and all others,


what about the telegraphs and audioalarm when running silent on E-Machines?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Dec , 2016, 02:49
Tore, we know that the Germans do not used Tab Washers on the internal pipe flanges bolts but used Tab Washers on all pipe flanges bolts that penetrated the pressure hull.

Do you think the Germans used Tab Washers on all the external pipe flanges outside the pressure hull or only on the pipe flanges that penetrated the pressure hull?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 01 Dec , 2016, 03:06
Hello again Tore and all others,


what about the telegraphs and audioalarm when running silent on E-Machines?




Not sure if i remember correctly but reading the u-boat manual when you were in silent mode there was no audioalarm at all. Only the light was blinking. There was a switch somewhere where you could control this.  3 modes. Off/Audioalarm & light bliking/ blinking only.   I may be wrong. Have been reading so much information that it all becomes a mess in my head :) 


But in game i this could be a cool extra layer of management. If you forget to manage telegraph switch modes when in silent run and give a new order with alarm then your noise level goes trough the roof and enemy could potentially locate your position.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2016, 03:53
Tore, we know that the Germans do not used Tab Washers on the internal pipe flanges bolts but used Tab Washers on all pipe flanges bolts that penetrated the pressure hull.

Do you think the Germans used Tab Washers on all the external pipe flanges outside the pressure hull or only on the pipe flanges that penetrated the pressure hull?
Simon.
I cannot remember for sure, but would be inclined to think they would use tabwashers or other locking devices on essential pipeflanges like fuel compensatingwater and ventducts.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2016, 05:04
Karel.
You remembered right, in silent run mode the enginetelegraphs had  switches on the controlbox in the controlroom enabling to disconnect the audible singnal system. In fact we used this system during night not to disturb sleeping crew under normal circumstances. Down below is an image of the control box which I picked from Dons Skizzenbook which I guess comes for sale next year.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Dec , 2016, 15:21
Hello Mr. Tore,


While surface running there is an air inlet ventilation stack and an air outlet ventilation stack... I guess the inlet stack is on the Starboard side in back of the tower under the bridge deck, is that correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 Dec , 2016, 15:55

Hi Don,

While surface running there is an air inlet ventilation stack and an air outlet ventilation stack... I guess the inlet stack is on the Starboard side in back of the tower under the bridge deck, is that correct?


You are right, the ventilation inlet trunk is at starboard side, behind the conning tower, inside the conning tower casing, under the Wintergarten platform.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Dec , 2016, 00:11
Don and Maciek.
The dieselair intake is as you said on stb side and the  large airduct goes  outside the pressurehull to the main dieselair hull  inletvalve. In the engine room it splits in stb and port duct ending at the bordsides behind the engine towards the bilges. Surfaced in bad weather the seawater from the ducts gushed down to the bilges which was the purpose for the design. I once experienced on U 926 KNM Kya after a refit during a testdive we had a severe leakage on the dieselair intakevalve, filling up the whole duct to the hullvalve being shut. The effect was we went down like an elevator and we had to blow all the ballasttanks before we finally stopped at 117 meters.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Dec , 2016, 21:01
Hi Tore,

Any idea that valve 'b' could look like, on Plan 10 : Fuel Oil Compensating System?

http://www.uboatarchive.net/U-570/U-570Plate10.htm (http://www.uboatarchive.net/U-570/U-570Plate10.htm)

PS. Don have you see any photo's of this valve?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2016, 19:13

Hi Simon,




I don't have a sure answer to your question...  Only an unsure opinion - I have attached a photo as a possibility (Note I highlighted the valve in question). I believe the valves in question are a three way cock with a 'T" plug and a means to limit the valve to only 2 positions...




The image attached seems to qualify for the "b" valve going to FBT 4 port side because it is far enough ahead of the Q Tank. It looks to be low enough to fit into the scheme of things, and it has a means to limit the valve movement.  There is a red metal stake that extends into the valve hand wheel spokes which will limit the valve selection...  Hopefully Mr. Tore or Maciek will have a definitive answer to your question instead of my 'SWAG"...




Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Dec , 2016, 21:55
Hi Don

From what I know valve 'b' is outside the Pressure Hull.

To me the valve in the picture look like a high pressure air valve.

It like you said we will need to wait for Tore or Maciek.

Simon
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2016, 00:22
Hi Simon,


I believe you should wait for a response from Mr. Tore or Maciek... I was just thinking of a drawing in Skizzenbuch where a valve for the header tank or sea water selection was located at the bottom of the saddle tanks.  If they had to change the selection, then the valve stem would need to come through the pressure hull to change from the fuel oil mode to the ballast mode.

Skizzenbuch -
"The compensating water pipes goes from the header tank to a small chamber (about 1.5 % of the tank volume) at the bottom of the tank, from this chamber a short pipe goes into the tank bottom and an equalizing pipe directly to the sea. The two connections are controlled by a double seated selector valve operated from the casing. The valve has only two positions, either to the fuel tank or direct to the sea. When in the fuel oil tank configuration the Kingstons are shut and the selector valve open to the fuel tank and thus shut to the sea."

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Dec , 2016, 00:47
Hi Simon,


I believe you should wait for a response from Mr. Tore or Maciek... I was just thinking of a drawing in Skizzenbuch where a valve for the header tank or sea water selection was located at the bottom of the saddle tanks.  If they had to change the selection, then the valve stem would need to come through the pressure hull to change from the fuel oil mode to the ballast mode.


Regards,
Don_

That very interesting! I had always presumed that the valve was under the deck and not in the saddle tank. I have even draw this valve under the deck in my 2-D drawing :-[

Don, have you come across any diameter of the pipes of the Fuel Oil Compensating System? Tore and I talked about this a few years back, and guessed something about a diameter of 75 mm but I am worry if this is too big ???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2016, 01:13
Hi Simon,


I have no idea as to the pipe diameters...  I only know from what I have learned from Mr. Tore and Maciek plus a little research on my own.


Hello Mr. Tore,


Down like an elevator aye!  And the problem was caused just by water in the inlet stack and the inlet line?  Was Kya equipped with the later Schnorchel where the inlet pipe went crossed-over to the diesel air trunk? If that was the case, then the diesel air trunk above the pressure hull could also get flooded and that extra weight increase would be huge???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2016, 02:26

Simon- Don.
Sorry being late in answering. We  never or very seldom used the fuel mode of the saddle ballasttanks, as we operated the VIICs as Coastal submarines. Hence I have not a personal experience of operating same. Transfering a ballasttank into fuelconfigurating requires some preparation. Of course the ventducts have to be shut, the blowing pipe both HP air and exhaust has to be locked shut, but nevertheless the compensating water pipe is in place and in ballasttank configuration you have to take measures to prevent blowing air into the compensating system.
In the bottom of the external ballast/fuel tanks the compensating water is checked by a selectorvalve D on the plan 8 this valve has two positions either open directly to the bottom of the tank and shut to the sea (fuelmode) or (in ballast mode) via a recess in the tank ( to prevent possible oilspill) to the sea and shut to the tank. My rough sketch below might explain the idea.The selector valve sits on the top of the pipe in the tank like some of the fuel testingvalves but are operated from outside the pressurehull ( not in the controlroom). The system prevent, in ballast mode, that  the compensating system don`t get higher pressures than the head of the compensating expansion tank in the towercasing regardless of the depth of the submarine and is not influenced by HP airblowing of the ballasttank.  Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Dec , 2016, 02:31
The image attached seems to qualify for the "b" valve going to FBT 4 port side because it is far enough ahead of the Q Tank. It looks to be low enough to fit into the scheme of things, and it has a means to limit the valve movement.  There is a red metal stake that extends into the valve hand wheel spokes which will limit the valve selection...  Hopefully Mr. Tore or Maciek will have a definitive answer to your question instead of my 'SWAG"...


The red medal stake is the drive shaft of the FBT 4 flooding valve.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2016, 12:54
Hi Maciek,


I believe you are not looking at the red metal stake that I was referring to...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Dec , 2016, 15:19

Hi Don,


I believe you are not looking at the red metal stake that I was referring to...


Indeed, I was looking on wrong stake. However the element you are referring to is (in my opinion) the MBT 3 blowing line check-valve.


Note that this element is located at the (curved) top of MBT 3 (it is not pressure hull). If it would be stake for the selector valve in question, it had to penetrate MBT 3 walls two times (it would not be desired).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2016, 15:55
Hi Maciek,


Your photo is much better than mine.  However, I was thinking of something like this...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Dec , 2016, 18:59
Hi Maciek,


Your photo is much better than mine.  However, I was thinking of something like this...


Regards,
Don_

From this viewpoint, the line look like its working its way up pressure hull.

(https://c5.staticflickr.com/6/5595/31303520332_893ed3d819_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Dec , 2016, 20:03

Simon- Don.
Sorry being late in answering. We  never or very seldom used the fuel mode of the saddle ballasttanks, as we operated the VIICs as Coastal submarines. Hence I have not a personal experience of operating same. Transfering a ballasttank into fuelconfigurating requires some preparation. Of course the ventducts have to be shut, the blowing pipe both HP air and exhaust has to be locked shut, but nevertheless the compensating water pipe is in place and in ballasttank configuration you have to take measures to prevent blowing air into the compensating system.
In the bottom of the external ballast/fuel tanks the compensating water is checked by a selectorvalve D on the plan 8 this valve has two positions either open directly to the bottom of the tank and shut to the sea (fuelmode) or (in ballast mode) via a recess in the tank ( to prevent possible oilspill) to the sea and shut to the tank. My rough sketch below might explain the idea.The selector valve sits on the top of the pipe in the tank like some of the fuel testingvalves but are operated from outside the pressurehull ( not in the controlroom). The system prevent, in ballast mode, that  the compensating system don`t get higher pressures than the head of the compensating expansion tank in the towercasing regardless of the depth of the submarine and is not influenced by HP airblowing of the ballasttank.  Tore

Hi Tore, Don & Maciek.

Does this valve need to be in the saddle tanks?

If you place this valve under the deck and right next to the saddle tank this seem to me a have a few advantages than being within the saddle tank (Fig. 1). Can be easily accessible and easier for maintenance.

I also checked my U-boat plans and there an opening in the saddle tank between frame 38 & 39. You can see this opening on U-995 (Fig. 2) (It has been welded up in the photo). This is very likely the opening to the sea.


(https://c8.staticflickr.com/6/5680/30641885583_7d2a8c9783_o.jpg)
Figure 1.

(https://c1.staticflickr.com/6/5701/31304414752_7b00bf983c_o.jpg)
Figure 2.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2016, 22:36
Hi Simon,


That all looks like a possibility...  However, I am very concerned about conjecture at this point.  I still can't understand the hand wheel gear driving a worm shaft that seems to go to a pipe.  That makes no sense to me. To say the least, I'm very confused at this point about the selector valve for the saddle tanks... 


Hello Mr. Tore,


While searching through my U-995 CD I found the drive shaft for the FBT 2 saddle tanks Kingston valves.  I have attached the image.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Dec , 2016, 00:00

Hi Gentlemen,


Your photo is much better than mine.  However, I was thinking of something like this...

From this viewpoint, the line look like its working its way up pressure hull.

(https://c5.staticflickr.com/6/5595/31303520332_893ed3d819_o.jpg)


The HP line goes up and then to stb, to the blowing distributor.


That all looks like a possibility...  However, I am very concerned about conjecture at this point.  I still can't understand the hand wheel gear driving a worm shaft that seems to go to a pipe.  That makes no sense to me. To say the least, I'm very confused at this point about the selector valve for the saddle tanks... 


This is not a worm gear. This is how the valve is constructed. I have attached the photo of another valve from the bow torpedo room and another from control room (FBT 4 hull blowing valve stb).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2016, 00:52
Hi Maciek,


Thanks for the info about the valve...  I was thinking of a mechanical hand wheel with a worm gear shaft.  It looks like you are right about the valve in question, and it's attached to the upper area of MBT 3; I'm not sure where it goes? Perhaps to an air pressure gauge? That would be one means to know the pressure inside MBT 3 when blowing the tank...  Is what looks to be a red spring latch just a reminder that they had better know what they are doing before changing the valve setting?


I'm still not sure where the selector valve is physically located for FBT 2 and 4; inside the saddle tanks or above and under the deck like Simon suggests?  I guess I have a lot of questions...  It seems the more I learn about the Type VII, then there is the more I don't know...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Dec , 2016, 01:38
It looks like you are right about the valve in question, and it's attached to the upper area of MBT 3; I'm not sure where it goes? Perhaps to an air pressure gauge? That would be one means to know the pressure inside MBT 3 when blowing the tank... 


This is line going to the blowing manifold. See the attached drawing (I marked the line with green color).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2016, 01:53
Hi Maciek,


Great work...  You convinced me that this line is for blowing MBT 3! It seems like such a small air line to blow such a huge ballast tank (MBT 3).  Comparing the size of the blowing line to the size of the venting valves (2) for MBT 3 in the venting trunks... Since the blowing line is such a small diameter have you ever read as to how long it took to blow MBT 3 (even partially blow)?

With the differential in vent and blowing diameters, then diving time would be faster, and surfacing time would be much slower...


I see there are two blowing valves for MBT 3 Port and Starboard...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Dec , 2016, 02:16

Don,


Great work...  You convinced me that this line is for blowing MBT 3! It seems like such a small air line to blow such a huge ballast tank (MBT 3).  Comparing the size of the blowing line to the size of the venting valves (2) for MBT 3 in the venting trunks...


The diameters of the blowing lines: internal 17 mm, external 20 mm.
As a point of interest, the regulating tanks and Q-tanks blowing lines diameters are: internal 22 mm, external 26 mm.


Since the blowing line is such a small diameter have you ever read as to how long it took to blow MBT 3 (even partially blow)?


No, as I recall, I have never met such data. But knowing the flooding holes cross-area and blowing air pressure and amount, the time could be possible to estimate.
If I remember correctly, Mark has made such calculations.


With the differential in vent and blowing diameters, then diving time would be faster, and surfacing time would be much slower...


I'm not sure if flooding cross-area did not have greater influence on blowing and flooding time than vent and blowing lines diamater.


I see there are two blowing valves for MBT 3 Port and Starboard...


Yes, you are right. I was not able to locate stb valve. If both valves were located symmetrical, the stb one should be located near the aft diving plane operating station. But there are oxygen bottles on the deck. So I guess, that the stb valve is located near (under) the blowing distributor.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2016, 02:39
Simon.
I guess you are right in assuming the selectorvalve for the compensatingwater could be outside the saddletank.In spite of an extra pipe it is much simpler and eliminates the stuffingbox for the valvespindle. You suggestion for the valvecasing could be correct I enclose an image of a selector valve in the fuelsystem.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2016, 02:54
Don.
The image of your blowingvalve is indeed the port blowingvalve for MBT3. As you know you have a central bulkhead in MBT3, allthough the bulkhead is not  pressure/watertight the tank still requires two blowingvalvs as well as two ventvalves.
 What you assumed was a wormdrive is the housing for the checkvalve which is incorporated in the blowing valve casing. This is the classical ballasttank blowvalve and all the blowvalves have a non return/checkvalve.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2016, 06:38
Simon.
Compensating water selector valve saddle fuel/MBT 2&4. May be an execution as below and possibly a removable T bar extension?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Dec , 2016, 10:33
Simon.
Compensating water selector valve saddle fuel/MBT 2&4. May be an execution as below and possibly a removable T bar extension?
Tore

This was how I had always imagined it was. Under the deck and with a removable ‘T’ handle. I got the idea a few years back after seeing the same valve in your other post.

I will try to do some drawing of my idea and post them this weekend.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2016, 13:51
Hello Mr. Tore and Simon,


I looked at the starboard side of U995 and the hole for the compensating water to the sea are questionable... I have attached the images...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2016, 14:54
Hello Mr. Tore,


I have a very dumb question that is bugging me since this current discussion began...  Please see the drawing and straighten me out again. What am I missing?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2016, 00:13
Don, It is not a dumb question and the arrangement of the two pipes is an assumption. The only answer I can give is the footvalve of the system is a double seated valve with two possible positions either to connect the fueltank with the header tank in the fuel configuration to provide compensating water or to put the ballasttank in connection with the sea. The only reason I can see for the latter configuration is to have a relief/safety arrangement for a possible blowing of the ballast tank with the Kingstons shut thus prevent overstressing the tank. Otherwise you are right in you statement about the fuelcontamination prevention of the sounding system during fuelling.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2016, 00:41
Tore, does the opening to the sea needs to be at the bottom of the saddletank?

In the photo below you can very clearly see a pipe opening (Blue arrow).

(https://c2.staticflickr.com/6/5567/30669838833_225deb22ab_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Dec , 2016, 01:01
Hello Mr. tore,


I have a NAVPERS 16160 manual for the US Fleet Type Submarine and they have Ballast and Water Compensated RFO tanks as well.  They have a valve inside the pressure hull that channels the water to a pipe that extends to the bottom of the tanks.


I have a problem with Skizzenbuch pages 81 through 83 where  I'm not sure if it is accurate? I possibly need to change the drawings on all 3 pages and the text on page 83.


"The compensating water pipes goes from the header tank to a small chamber (about 1.5 % of the tank volume) at the bottom of the tank, from this chamber a short pipe goes into the tank bottom and an equalizing pipe directly to the sea. The two connections are controlled by a double seated selector valve operated from the casing. The valve has only two positions, either to the fuel tank or direct to the sea. When in the fuel oil tank configuration the Kingstons are shut and the selector valve open to the fuel tank and thus shut to the sea (see the diagrams on page 78)."


1. Indicates a small chamber near the bottom of the tank
2. A short pipe that goes to the bottom of the saddle tank
3. A equalizer pipe directly to the sea
4. The two connections are controlled by a double sealed selector valve from the casing
Plan 10 shows the selector valves (b), but there is no indication that the valve is internal to any tank. Thus the thought of the selector valve being under the deck casing, but I'm not sure...
I did a guess drawing with 1 pipe and the selector valve under the deck.  The selector valve has 3 positions:
1. Off
2. Water to the tank
3. Test/water overboard
What do you think?




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Dec , 2016, 01:11
Hi Simon,


Could you please email me that photo without the arrows if you have one?  I need a larger size for resolution if possible...

I pulled Skizzenbuch from my dropbox so I could make changes on pages 81 - 83 (I don't want my managing editor getting it yet)...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2016, 01:43
Don.
I Guess 4.    ...... double sealed selectorvalve......is a misprint. I am not sure of the three positions of the selector valve 1. Off?
I guess you have only two positions either to the tank or to the sea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Dec , 2016, 02:01
Hello Mr. Tore,


OK, I changed the drawing...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2016, 02:11
Hi Simon,


Could you please email me that photo without the arrows if you have one?  I need a larger size for resolution if possible...

I pulled Skizzenbuch from my dropbox so I could make changes on pages 81 - 83 (I don't want my managing editor getting it yet)...

Regards,
Don_

Sorry Don, that is the only one I have :'(

I got it from Siara (http://models.rokket.biz/index.php?action=profile;u=44 (http://models.rokket.biz/index.php?action=profile;u=44)) many years ago. I never seen it in a book or anywhere on the Internet.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2016, 02:17
Simon.
I don`t see any particular reason to have the outlet at the bottom of the tank, might be you have found a solution by your photo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Dec , 2016, 19:56
Hello Mr. Tore,


I uploaded Skizzenbuch back to dropbox.  If at all possible would you review pages 81, 82, and 83 because I modified your drawings and updated the text to reflect the changes... Actually there was not that much to change.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Dec , 2016, 21:26
Here are some early modelling of the valve.

(https://c1.staticflickr.com/1/324/30657732984_8478f66ced_o.png)
Fig. 1. Top view. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/262/31352349552_1493d67aba_o.png)
Fig. 2. Port view. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/751/30657744544_857e7cfc02_o.png)
Fig. 3. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/200/31461122716_ba397e8c45_o.png)
Fig. 4. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/63/31383157721_585832e6cf_o.png)
Fig. 4a. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/57/31498725705_a5b2d62363_o.png)
Fig. 5. Deck hatch closed. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/676/31352334952_68dc8b6e85_o.png)
Fig. 5a. Deck hatch open. Images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/199/31352331152_49497fee72_o.png)
Fig. 5b. Deck hatch open. Images has been resized. Click to view original image.


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2016, 00:05
Hello Mr. tore,


If I remember correctly, you said U-926 Kya had a damaged MBT 3 which was done by accident...


OL Hellmut Rehren was the CO who joined the Kriegsmarine back in 1939 and worked his way up the ranks until 1943 when he became a OL. He was given command of U-926 in February 1945 and had to surrender his 1st command on 9 May 1945.  I'm willing to bet that he or his EO were NOT very happy about that prospect.


The type VII C has 12 HP storage canisters and it would be very simple to shut the Kingstons and the emergency vent valves and vent valves, and then blow MBT 3 while running on the surface to surrender with the hatches open.  If the pressure of 16 bars from the 1st attempt didn't blow the end caps off the ballast tank (not likely), then recharging the HP canisters and the 2nd 16 bars surely would do the job...


Formula...


PV = PV


Canister pressure is 201 bars at 3.936 m3
MBT 3 volume is 47.75 m3 (Pressure would be = 16 bars) if all is blown into the tank.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2016, 01:19

Don.
I`ve checked Skizzen book page 81 thru 83 and have marked off my findings as per images below. I guess a misunderstanding has ocurred as to the gate valves in the MBT 2&4 ventingsystem. You don`t have both gatevalves and cumbersome blindflanges in the system, you have gatevalves instead of cumbersome blindflanges. As you know a gatevalve is almost  an easy removable blindflange.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2016, 02:22
Don.
Kya`s  ex. U 926 structual damage. 12 Storage containers seems a lot, we had only 3 when I was onboard. I am a bit confused as to HP blowing of the storage container as you know the containers are not equipped with any HP airconnection and are simply a pressureproof container with lid like the ammocontainers. Anyhow Boyle Mariottes low is valid and Storage containers might be a confusion with the HP air flasks or airbottles as we say. 205 bar with an expansion to 10-25 bar makes a considerable volume increase, but a detail which is forgotten is the temperature drop according to Boyle Mariottes P1xV1/T1=P2xV2/T2. Such a temperaturdrop during a long blowingtime might cause freezing of  the blowing valve which is one of the reasons the main blowing panel in the controlroom has an emergency blowing valve shortcutting the main blowing valve in case of freezing.
Back to U 226 and the structural damage. it is a long story which I might revert to if any interest, but the conclusion was, in late April/ early May grossadmiral Dønitz ordered all the operational uboats to Norwegian ports as Norway was going to be the center for the German submarine high command for the last desperate fight. More than 100 boats arrived causing a capacity problem at the surrender and the Allied forces decided  to remove these boats to Scotland sailing the boats by the german crew. The operation was named Pledge, and a Norwegian naval submarine delegation took part in an investigation as to which Uboats were fit for the crossing to Scotland. I guess all but 11 were fit and amongst those 11 were , the U-995, U-926 and U 1202 which later were reconditioned and operated by the Royal Norwegian navy. The whole story is long and last year I wrote an article on the event in the main newspaper in Oslo, I have translated same to English.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2016, 02:50
Simon.
It`s a delight to see you are back with you amazing drawings, as many times we have to improvise and assume as no reliable images exist. I am still in doubt of the selector valve, not the position outside the tank. The selectorvalve is a double seated valve and we have such a selector valve in the trimsystem placed in the controlroom. It might be this valve is closer to the prevously indicated.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Dec , 2016, 11:20
Hi All

Yesterday I think I found the valve and piping on U-534.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2016, 11:47
Hi Simon,


Those photos seem to verify that the selector valve was below the deck... Great investigation and find!  It's amazing that some of the tanks internal surfaces are not rusted like the internal pressure hull. Perhaps they stayed in tact and were not flooded after all those years at the bottom of the sea.

Hmmm... I just noticed that the kingstons are shut.  That would mean they were in a fuel oil storage configuration.  That could account for the better condition of the tank's internals.

Mr. Tore,


Just for my own personal knowledge, what is the difference between a selector valve, a sealed selector valve, and a double sealed selector valve?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2016, 12:10
Hello Mr. Tore,


I made the suggested changes to pages 82 and 83 and uploaded the Skizzenbuch update to dropbox.  Thank you for reviewing the text...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Dec , 2016, 00:38

Don.
A double seated valve is probably not a precise name as f.i. a gatevalve can be double seated using both side of the "gate". However in this specific case of a compensator selector valve it means a valve having two seatings which can only be put in either-or position. The image below is a double seated valve having one inlet and two outlet. For smaller pipes such a "valve" would be a three way cock, in the case of the valve below, the valve has to be operated to the end stops, up or down like the selector trimvalve in the controlroom shown below. I don`t think there is any mentioning of a double sealed valve in this connection, I guess this might be a misunderstanding.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Dec , 2016, 02:06
Hello Mr. Tore,


What is this lever for located near the GW Diesel engine on U-995?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Dec , 2016, 05:05

Don.
As you know U 995 is equipped with Krupp Germaniawerft main engines. Contrary to the MAN engines the GW engines were only partly supercharged in the upper outputs by a mechanical driven Roots blower. The blower is driven from the camshaft assembly in the aft end of the main engine and switched in at a given output and revs by a doublecone clutch. The handle you refer to is the handle for same. Simultaneously to engaging the blower is the shutting of the natural aspirating air inlets for each cylinder in order to accommodate the common airduct for the supercharging air to the cylinders. This is done by rotating the natural aspirating inlet valves by the same handle. May be the image below is of some help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Dec , 2016, 23:11
Hello Mr. Tore,


It looks like there is no interlock for reversing since U-995's GW Diesel engine is non-reversing, and the handle is different from the drawing Plan 30 with the reversing interlock.


It looks as if the handle is down (Aspirater mode), and raised up (Supercharged mode) is that correct...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2016, 00:13
Don.
As you know the plate 30 as published is from the manual of U 570 later HMS Graph, comissioned in 1941, and as such shows the GW engine in a direct reversible execution. The later non reversible GW engines had most of the maneuvring gear removed and simplified so the plate 30 is not relevant to every detail for the U 995. I believe the lever for the roots blower was raised in an engaged position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Dec , 2016, 15:42
Tore, I noted on the early Type VIIC's, there are small bass labels next to the deck hatches. Most likely identifying the hatches. Do you think they carried on this practice with the late war U-boat?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 10 Dec , 2016, 18:54
Simon.
It`s a delight to see you are back with you amazing drawings, as many times we have to improvise and assume as no reliable images exist. I am still in doubt of the selector valve, not the position outside the tank. The selectorvalve is a double seated valve and we have such a selector valve in the trimsystem placed in the controlroom. It might be this valve is closer to the prevously indicated.
Tore

Hi Tore

Here are the new drawings of the Selector valve (Figure 1). I cannot get it to fix in the space available on the post side of the main ballast and reserve fuel oil tank 2 :(

Looking that the pictures of U-534, my original Selector valve (Figure 2) looks more correct. I might leave the Selector valve till later, until we get better pictures or after I add the saddle tanks to my model, to see how much real space there is.

Simon

(https://c1.staticflickr.com/1/658/31190153150_e8b10d52a0_o.png)
Fig. 1. New Selector valve. (Images has been resized. Click to view original image).

(https://c1.staticflickr.com/1/277/31562308605_2a357bd81c_o.png")
Fig. 1a. New Selector valve. (Images has been resized. Click to view original image).


(https://c1.staticflickr.com/1/288/30753048773_6d9eee05f9_o.png)
Fig. 2. Original Selector valve. (Images has been resized. Click to view original image).


(https://c1.staticflickr.com/1/600/30753046833_82fdca9b6b_o.png)
Fig. 2a. Original Selector valve. (Images has been resized. Click to view original image).
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2016, 01:05
Simon.
Your selector valve fig two is probably correct for an inboard fuelvalve but for an outboard valve your fig 1 would probably be better with a few modification. The stuffingbox should be a bit different. Below I have tried to indicate my idea. The threaded part of the valvespindle should be on the top of the spindle whereas the spindle should be without threads in the valvehousing where the packing materiel is located. I can not remember any brassplates for identification on the later VIICs, in the latter part of the war the Germans hardly used any brass.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2016, 11:47
Tore, the hull valves ('h') for the low pressure exhaust gas for main ballast and reserve fuel oil tank 2 & 4 http://www.uboatarchive.net/U-570/U-570Plate16.htm (http://www.uboatarchive.net/U-570/U-570Plate16.htm)

Which valve do you think is best figure 1 or 2?

Figure 1.
(https://c2.staticflickr.com/1/404/31579257585_109fb9d071_o.jpg)
Figure 2.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2016, 11:47
Simon.
Your selector valve fig two is probably correct for an inboard fuelvalve but for an outboard valve your fig 1 would probably be better with a few modification. The stuffingbox should be a bit different. Below I have tried to indicate my idea. The threaded part of the valvespindle should be on the top of the spindle whereas the spindle should be without threads in the valvehousing where the packing materiel is located. I can not remember any brassplates for identification on the later VIICs, in the latter part of the war the Germans hardly used any brass.
Tore

Hi Tore,

Thanks for the information on the stuffingbox, I have always wonder about this detail. Below is the updated drawing.

(https://c1.staticflickr.com/1/95/31432337902_437be8e1d8_o.png)
Image has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2016, 13:05
Simon.
I Guess your figure 2 would be the appropriate, just remember not to have any threads on the valvespindle going through the stuffingbox.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2016, 14:14
Simon.
I Guess your figure 2 would be the appropriate, just remember not to have any threads on the valvespindle going through the stuffingbox.
Tore

It’s not perfect, but it came out much better than I thought it would. Hard to improve the model until we get some better photos or a diagram of valve.

(https://c1.staticflickr.com/1/435/31544727356_9a720576b1_o.png)
Image has been resized. Click to view original image.

(https://c1.staticflickr.com/1/609/31435819512_27433bc948_o.png)
Image has been resized. Click to view original image.

(https://c1.staticflickr.com/1/109/30772610183_db1275ba31_o.png)
Image has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2016, 14:32
Tore, according to the Kriegsmarine Color Codes for piping, bunkers, cells, tanks and pumps & the Design Studies - Type IXC, valves were marked with the same color code as the piping. Do you think the outboard valve handle were painted or was it a waste of time?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2016, 14:38
Simon. Looks fine,  but might be you should make the flange bolts a bit shorter, the protruding threaded part outside the flange is of no use and make the dismantling more cumbersome than necessary.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Dec , 2016, 15:18
Simon. Looks fine,  but might be you shold make the flange bolts a bit shorter, the protruding threaded part outside the flange is of no use and make the dismantling more cumbersome than necessary.
Tore

Thanks, with update  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2016, 23:00
Simon.
As far as I remember I don`t think the outbard valves had any colour code.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Dec , 2016, 14:23
Hello Mr. Tore and Simon,


Is this the general idea behind the water compensation valve... My $0.02..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 01:08

Simon, Don and others.
I woke up this night realising I have been conducive to a massive sabotage of the VIIC construction and am urging to come to a rescue. :-[ The simple design of the compensating valve having an outlet under the casingdeck would probably act as a modest vent for the fuel ballasttanks 2 and 4 when shutting the valve to the compensatingtank and simultaneously open the ballasttank to the atmosphere while surfaced. My previouse (but  not so elegant :) ) arrangement having the outlet by a second pipe down to the bottom of the saddletank in contact with the sea, prevented such venting. I like the idea of the compensating watervalve outside the saddletank, but I guess we have to have a second pipe down to a seawater connection at the bottom of the tank thus maintaining the ballast tank pressure while surfaced. The system has to be intergrated in the ballasttank by having a connection to the sea at the bottom of the tank in order to keep the ballasttank pressure. The seapressure at the bottom of the tank while surfaced would do this just as the open Kingstons are doing. I am sorry about this and as many times before I am afraid we probably have to find a new solution by the small expansion tank having seaconnection in the bottom of the tank. Does anybody have an image of the small bottom expasiontank?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 02:12
Hello Mr. Tore,


I'm staying up so we can discuss the compensation system...  Plan 13 for the GW Diesel engine and the water circulation system seems to indicate that the cooling water:


1. First the cooling water goes to the exhaust muffler.
2. Then the cooling water looks to have some vents to allow the water to go to the sea.  I assume that don't want non-circulation water in the muffler because that would not cool the muffler. Therefore some of the cooling water must escape from the muffler.
3. Then the remaining cooling water goes to the header tank under the winter garden.


At this point we have cooling water in the header tank under pressure because the flow volume exceeds the leakage volume through the mufflers. 


On Plate 10 we see where the cooling water is distributed to all the internal and external fuel oil tanks. 


1. I see no problem if all of the tanks are in the fuel oil compensating mode because none of the tanks are open to atmospheric pressure and the cooling water system is closed.
2. If the 4 saddle tank compensation valves had a 3 position  "OFF" then that would eliminate opening the water compensation system to the atmosphere.
3. The 2nd position on the 4 saddle tank compensation valve would be for "Testing" the water pressure and flow of the compensating water.


This solution would only require 1 compensating water pipe in the saddle tanks... What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 02:38
Hello Mr. tore,


Back to the valve above the saddle tank. 


1. In the water compensation mode - the line is not open to the atmosphere but from the header tank to the saddle tank (Closed system).
2. Saddle tanks not in the water compensation mode - the valve has the saddle tank pipe shut (Closed system), and the valve has the header tank water flowing from the 2nd valve pipe to the sea...

If the water pressure from the diesel engine is not adequate to allow the drainage from the 4 saddle tank valves and maintain adequate water pressure to the internal tanks, then we would need an "Off" position on the water compensation valves under the deck.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 03:21
Don.
I see your point of view, but my problem is if you look at the compensator water plan,  the  headertank outlet for the compensating water to the compensatigsystem is at the bottom of the headertank (no pipe up in the tank) and if the supply pipe to the saddletanks in the ballast configuration goes direct to the sea you`ll  drain the headertank in surfaced position..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 03:43
Plan 10


Let's discuss Plan 10

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 03:52
The inlet pipe is up in the header tank...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 03:57
If the surface position will drain the header tank, then the 4 water compensation valves need to have an "OFF" position....

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 07:38

Don do you ever sleep? ;D
I am convinced we shall eventually find a good solution within our free design, however as we are looking for a solution which should be as  close as possible  to the real design  we would have to use the resources available. The only reliable material I have at hand, as I explained previously we did not use the system, is plan 10 and a report on the system made by RN after an examination of U 570 later HMS Graph. An extract is below as well as plan 10. To me it seems obvious that the selectorvalve is a double seated valve ( not a cock) having three connections (positions): 1. from the compensating headertank. 2. compensating water to the bottom of the fueltank and 3. to the sea. It is only possible to select either 2 or 3. This was behind the rather un-elegant two pipe solution I proposed in the beginning.
I welcome any other solution within the basic infos available.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 07:50
Hello Mr. Tore,


Where did that text come from?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 09:06

Don.
From www. uboat archive.netU-570/British report.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 10:57
Hello Mr. Tore,


How does this look?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 12:02
Don.
This was my idea from the beginning, but we are not able to locate the expansion tank and the access to the sea.
My idea about the headertank is below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 12:20
we are not able to locate the expansion tank and the access to the sea...

From C.B. 4318 report "The tanks are build of light plating..."

I rechecked my drive photos of U-1021 and U-352 and I cannot found kind structure in these areas. The tanks must be the first thing to rot away at the bottom of the ocean :(

I will keep looking.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 12:41

Don.
From www. uboat archive.netU-570/British report.
Tore

Hi Don & Tore

I never thought about looking at this report for pipe dimensions. I have always estimated the pipe dimensions by plans and photographs. I was just flipping through the report and notice on page 40 "The diameter of the ventilation pipes leading into the ship from the conning tower fairwater is approximately 9 - 3/4"." which is 247 mm. I just checked my 3-D model and I had estimated this pipe dimensions as 246 mm :D Sorry about the inaccuracy of my model I will fixs this and will do better next time ;D ;D

This can give us confidence that we are heading in the right direction to workout how a U-boat works and is constructed!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 13:35

Don.
From www. uboat archive.netU-570/British report.
Tore

Hi Don & Tore

I never thought about looking at this report for pipe dimensions. I have always estimated the pipe dimensions by plans and photographs. I was just flipping through the report and notice on page 40 "The diameter of the ventilation pipes leading into the ship from the conning tower fairwater is approximately 9 - 3/4"." which is 247 mm. I just checked my 3-D model and I had estimated this pipe dimensions as 246 mm :D Sorry about the inaccuracy of my model I will fixs this and will do better next time ;D ;D

This can give us confidence that we are heading in the right direction to workout how a U-boat works and is constructed!

 I found two more measurements in the report.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 15:37
Tore & Don,

I think I found the expansion tank ;D

Couldn't the small round shape at the very bottom of the saddle tank which is also right next the compensating pipe and the kingstons be the expansion tank??

It has a smaller diameter pipe coming out of it (its been cut in half but you can see it above and heading forward to the compensating valve).

(https://c2.staticflickr.com/1/379/31396301001_3c29011c41_o.jpg)
Images has been resized. Click to view original image
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 15:55
Maciek & Don, have you seen any size measurements for the high pressure gas bottles?

I also found these pictures of U-106 high pressure gas bottles  :)

(http://www.britainatwar.com/central/images/gallery/1644.jpg)

(http://www.machuproject.eu/machu_cms/media/Wreck_id_256/luchtfles.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2016, 17:57
Hello Mr. Tore,


I updated pages 81, 82, and 83 text and I modified the 6 drawings to match with our latest discussions about the header tank water compensating system.  I uploaded the latest version of skizzenbuch into dropbox. If you have the time would you please review what I have done and let me know if anything is not correct, or needs some changes to those 3 pages.


I was a little worried that my Schiffer managing editing would look for the files which I removed from dropbox... So I stayed up over night changing the drawings and struggling with the text.  Then I had to redo the text files (schiffer specific files), update section 1 of skizzenbuch, re-join the 6 PDF files, and add the new drawings to the image folder, and finally upload all the files back to dropbox...


Just another day in paradise!


Good night to all,
Regards,
Don_


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2016, 23:36
Simon.
I guess the assumed image of the expansion tank of the IXC cutaway is probably the echosounder, I have previously been fooled by this image.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Dec , 2016, 23:54
Simon.
I guess the assumed image of the expansion tank of the IXC cutaway is probably the echosounder, I have previously been fooled by this image.
Tore

What make you think its the echosounder?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Dec , 2016, 00:08

Simon.
I found a description in some documents a few years back when I was looking for the expansion tank, unfortunately I do not remember the name of the source.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Dec , 2016, 13:31
Hi Simon,


This is a modern echo sounder used by fishermen...  Look familiar?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Dec , 2016, 13:50
Don, you found the echosounder! On a type IXC it is probably a good place to put it as shown on the cutaway image, a similar place in the saddletank on the VIIC would be wrong. Keep looking for a small expansion tank and a seaconnection in the saddletanks of a VIIC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Dec , 2016, 15:08
Maciek & Don, have you seen any size measurements for the high pressure gas bottles?

I also found these pictures of U-106 high pressure gas bottles  :)

(http://www.britainatwar.com/central/images/gallery/1644.jpg)

(http://www.machuproject.eu/machu_cms/media/Wreck_id_256/luchtfles.jpg)

Estimating off the U-Boat plans the measurement are.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Dec , 2016, 16:58
Hello Mr. Tore,


Echolot info taken from the German Type VIIC training manual...



"Each device consists of: transmitter, receiver and amplifier.  The shallow depth sounding device works noiselessly, while the deep depth device sends sound impulses which are audible.  Both devices are powered by the AC shallow and deep depth echo sounding converter located in the E-motor room.


The deep depth sounding device has three transmitters and three receivers which are mounted in the keel. The shallow depth sounding device has one transmitter and one receiver. Both are mounted on bottom of the hull, on the port side, near the munitions magazine."


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2016, 00:38
Don.
I should have remembered the position, but I don`t, in spite of sleeping almost on the top of it for 3 years. ;D My bunk, light blue, and the echosounder, red dot on the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Dec , 2016, 01:38
Hello Mr. Tore,


I had got a copy of the book which was in German about 5 or 6 years ago and struggled with the translation.  I Faxed each page to Captain Jerry Mason of the uboatarchive.net and he had Maciek to translate the book and it's on Captain Jerry's website. It took me several hours to find where I got the information in the first place.  Besides getting help from you about U-Boats, I need to start documenting where I got the info so I can find it again...  I don't have all that experience like you do in your head, and there is no one else around with the knowledge and who actually lived in the Type VII C U-Boat.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Dec , 2016, 02:27
Don.
The funny part of it is when we did a schnorcheling test in 1953 being 28 days submerged towards Greenland, the echosounder and good drafts with sounding contours was one of the major navigation instruments at that time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2016, 14:26

Hi Simon,

Maciek & Don, have you seen any size measurements for the high pressure gas bottles?


All high pressure air flask at type VIIC U-Boats have following dimensions:
capacity: 325 l
length: 2650 mm
diameter: 450 mm
Dehnung: 12% (it translates to lengthening but I'm not sure what it can mean)

so your estimation is very accurate.


Estimating off the U-Boat plans the measurement are.
  • Bottle width: Average 458 mm, SD = 21 mm, n = 9.
  • Bottle length Type VIIC’s: Average 2492 mm, SD = 20 mm, n = 4.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2016, 14:58

Hi Simon,


Simon.
I guess the assumed image of the expansion tank of the IXC cutaway is probably the echosounder, I have previously been fooled by this image.
Tore


What make you think its the echosounder?


In the book "Die Sonaranlagen der deutschen U-Boote" by Eberhard Rössler there is a description of the Echolot (Echosounder), which says that three sonic transmitters were located at port side, at the height of the Diesel engine room (just behind the bulkhead between control room and Diesel engine room).
On the photo attached by Simon we can see (if I'm not mistaken) the Diesel engine room, looking aft. In my opinion, the marked element is the most aft of the three sonic senders.


Note, that at the bottom of the opposite fuel tank, this element does not exist (if it would be expansion tank, it had to be there).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2016, 15:07
Don.
I should have remembered the position, but I don`t, in spite of sleeping almost on the top of it for 3 years. ;D My bunk, light blue, and the echosounder, red dot on the image below.
Tore


On page 429 of the Skizzenbuch there is visible location of the ultrasonic transducers.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2016, 15:44
Simon.
I guess the assumed image of the expansion tank of the IXC cutaway is probably the echosounder, I have previously been fooled by this image.
Tore


What make you think its the echosounder?


In the book "Die Sonaranlagen der deutschen U-Boote" by Eberhard Rössler there is a description of the Echolot (Echosounder), which says that three sonic transmitters were located at port side, at the height of the Diesel engine room (just behind the bulkhead between control room and Diesel engine room).
On the photo attached by Simon we can see (if I'm not mistaken) the Diesel engine room, looking aft. In my opinion, the marked element is the most aft of the three sonic senders.


I have attached the view of the bulkhead between Diesel engine room and control room (looking forward). The other (middle) sonic sender is visible there.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Dec , 2016, 16:29

Gentlemen,


regarding the expansion tank, reading the description of the ballast and fuel oil tanks in the German documents, I have found the following fragment:


Quote
Für Tauchbunker 2 und 4, Bb und Stb bei Betrieb als Tauchzellen.
Je 1 Sicherheitsrohr. Ist der Druckwasserschalter zu, stellt das Druckwasserrohr von Restwasser der Tauchzelle über Druckwassserschalter nach außenbords das Sicherheitsrohr dar.

Bei Betrieb als Treibölbunker ist ein Druckausgleich über die Druckwasserleitung bei offenem Druckwasserschalter möglich. Zur Vermeidung von Ölspuren ist die Druckwasserleitung in den Tauchbunkern in einen abgeschlossenen Raum zwischen zwei Spanten geführt. Verbunden ist dieser Raum mit dem Bunker durch ein gebogenes Übertrittsrohr, an diesen höchster Stelle ein Entölungsrohr angeschlossen ist.


I would translate it as follows (however please correct me if something is wrong):


Quote
For tanks 2 and 4, port and stb, used as ballast tanks.
Each tank is fitted with safety tube. When the pressurized cooling (compensating) water selection cock is closed, the residual water in the ballast tank overflows through the selection cock and safety tube overboard to the sea (my note: I guess - but I can be mistaken - that this description refers to the surfaced condition, when the pressurized cooling water is fed to the blown ballast tank).


When operating as fuel oil tank and when selection cock is opened, the pressure is equalized through the pressurized cooling (compensating) water system. To avoid the trail of the fuel oil, the pressurized cooling (compensating) water piping in the tank is enclosed in the space between two frames. This space is connected with the tank by means of the curved pipe (my note: maybe U-shaped pipe?). At the top of this curved pipe the de-oiling tube (my note: fuel oil venting/sounding/testing pipe?) is connected.


Maybe it somehow helps in further researches of the expansion tank.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Dec , 2016, 23:03
Hi Maciek,

That information could be interpreted is several ways... While running on the surface in the ballast mode:


1. The selector valve is in the Ballast configuration
2. The selector valve compensating water to the Ballast tank is shut
3. The selector valve now sends the compensating water to the Expansion tank at the bottom of the Ballast tank.
4. The small tube (Safety Tube) from the expansion tank is connected to the sea.


The "REPORT ON U-570 - H.M.S. GRAPH" on page 64 states...


They refer to the header tank under the tower as an expansion tank, and they also refer to a small tank at the bottom of each FBT (ballast tank) as an expansion tank. However, we refer to the tank under the winter garden as the header tank. Now their sentence makes sense...


"The expansion tank is always in open connection with the sea and thus the fuel tanks are always equalized and the only compensating water pressure which can be applied is due to the head of water in the expansion tank (Header Tank). This arrangement is necessary where direct blows are fitted and avoids the possibility of straining the tanks due to high pressure. The tanks are built of light plating and are tested to 15 lb. per sq. in."


Drawing attached.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2016, 07:40
Based on the info we have right now I have tried to put up  a sketch showing my assumtion of the ballast/ fueltank compensating system. The small "expansion" box of thin sheetmetal in the saddletank bottom is located between two frame lenghts remains the image documentation and I assume the fuel "drain" from the expansion box is connected to the testcock system under the casingdeck. The outlets under the casing deck shown on Simons image could possibly be the outlets from the sample funnels in the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2016, 12:17
Hello Mr. Tore,


The British report on U-570 states...  "The expansion tank is always in open connection to the sea..." In your drawing; If you are running in the ballast mode and submerged, then it looks like there is a possibility of having HP air entering the water compensating system with the small tube through the compensation tank at the bottom of the ballast tank when blowing the ballast.

I agree that the pipe in Simon's photo is most likely connected to the collector funnel on Plan 8a...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2016, 12:38
Don, if you follow the blue line on the image showing the ballast configuration you`ll see the ballasttank is in direct connection with the sea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2016, 12:44
The "compensation water box" in your drawing...  Is that the expansion tank at rhe bottom of the ballast tank?  Why would it ever have fuel oil at the top?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2016, 13:03
By having the expansion tank pipe connected to the fuel oil venting pipe...  As soon as the tank is full of fuel oil, then the fuel oil will enter the expansion tank during refueling?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2016, 13:25
Yes, the blue line through the selector valve does have the expansion tank connected to the sea in the fuel bunker configuration.  However, in the Ballast tank configuration the expansion tank is not connected to the sea other than through the open kingstons...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2016, 15:23

Don.
I guess we have a misunderstanding. On the image below I have marked a violet 1 for the ballast tank configuration, the selectorvalve is shut to the headertank and open to the sea. Seawater flows by a seapipe to the double seated selector valve and then to the small "expansion" tank, further by the bended (inverted U) pipe (shut drain cock) from the "expansion" tank into the ballasttank which then is in connection with the sea, thus acting as as "safety" line, relieving a possible excessive pressure in the ballast tank if the Kingstons are shut.
In the red circle marked fig 2 you have the system in fuelconfiguration having the selector valve shut  to the sea and open to the headertank, thus suppling compensating water at a pressure(head) from the headertank thru the "expansion" tank into the fueltank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Dec , 2016, 01:57
Hello Mr. Tore,


I see where you are correct as usual...  Could we compromise on the connection between the expansion tank and the fuel oil venting pipe.  See my attached drawing, or explain the reason for that connection.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Dec , 2016, 02:09
Hello again Mr. Tore,


I was thinking (Bad Don_ again)...  When the U-Boat is running on the surface with the saddle tanks in the fuel oil configuration, the internal and external pressure would be about 2 atmospheres. Water or fuel oil are not compressible. Let's say the U-Boat dives to 100 meters. Now, the external pressure is about 10 atmosphere and the saddle tank were sealed.  So the internal pressure is somewhat less than the external pressure I think???


Therefore, the expansion tank is open to the sea via the header tank and it provides the path for the saddle tanks pressure to equalize.  Since the liquids in the saddle tank are not compressible, perhaps the the expansion tank just applies the equalizing pressure (no expansion if any)...


Am I way wrong?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2016, 03:06

Don.
I guess you got it, and your fueloil venting ( draining) is workable, however the basics for my assumed design is the documentation available and Macieks reliable german source says: Verbunden ist dieser raum (expansiontank) mit dem bunker durch ein gebogenes Uebertrittsrohr an diesen hoeghster stelle ein entoelungsrohr angeschlossen ist. A bit freely translated:  the expansionbox is connected to the fueloil bunkertank by a bended overflowpipe which has a "deoiling" (oildrain) pipeconnection at the highest point. Hence the drain/venting connection on the top of the inverted U pipe. Macieks source could of course relate to an older design of VIICs but I guess we better stick to what is documented. We still lack an original image showing the arrangement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2016, 03:26
Hello again Mr. Tore,


I was thinking (Bad Don_ again)...  When the U-Boat is running on the surface with the saddle tanks in the fuel oil configuration, the internal and external pressure would be about 2 atmospheres. Water or fuel oil are not compressible. Let's say the U-Boat dives to 100 meters. Now, the external pressure is about 10 atmosphere and the saddle tank were sealed.  So the internal pressure is somewhat less than the external pressure I think???


Therefore, the expansion tank is open to the sea via the header tank and it provides the path for the saddle tanks pressure to equalize.  Since the liquids in the saddle tank are not compressible, perhaps the the expansion tank just applies the equalizing pressure (no expansion if any)...


Am I way wrong?


Regards,
Don_
Don.
When you are on the surface in fuelconfiguration the saddle tanks are via the selectorvalve in direct connection with the headertank and shut to the sea, Kingstons shut. Hence the pressure in the saddletanks is only that which is obtain by the head, hight of the headertank, above the saddletanks as for a normal fueltank. Submerged the pressure difference between the saddletanks and the sea shall still be only that of the headertank hight as the headertank is then connected to the sea by its overflowpipe as well as the swan neck on the top of the headertank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2016, 05:25
iquote author=Don Prince link=topic=921.msg19928#msg19928 date=1482005001]
By having the expansion tank pipe connected to the fuel oil venting pipe...  As soon as the tank is full of fuel oil, then the fuel oil will enter the expansion tank during refueling?


Regards,
Don_

When you are fueling, the fuel supply pressure forces the compensating water out of the saddletanks thru the compensating waterpipe, the compensating waterpipe ends about 10 cm above the residue water in the saddletanks. Close to the end of the fuelling you are all the time checking the compensating water outletflow from the testcock arrangement discussed. As soon as your testcock is showing fuel, you stop the filling. Possible fuelrests in the compensating watersystem is collected on the top of the inverted U pipe and "expansionbox" and can be drained later, when settled, by the test/draincocks. The headertank pipe ends in the bottom of the box,the possible fuel is on the top, thus you have a considerable, almost 1,5% of the tankvolume buffer to prevent fuel contamination of the compensating water system. This elaborate and complicated system has nothing to do with the environment people, they did not exist in the time of the VIICs, but at all cost to prevent an oilslick which might betray the submarines position.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Dec , 2016, 17:37
Hello Mr. Tore,


You convinced me about the design of the expansion tank piping in the saddle tank...  However, the actual function of the expansion tank is another question?


In the fuel oil configuration mode; the expansion tank seems to do nothing.  When diving at depth equalization is done from the header tank through the expansion tank and to the venting pipe at the bottom of the saddle tank.


In the water ballast tank mode; if there was no expansion tank just a pipe at the bottom of the saddle tank, then in heavy seas the Kingstons could be exposed above the water line.  This action removes the header tank back pressure and may flush the header tank.  To eliminate the possibility of flushing the header tank, the expansion tank was added.  Therefore in heavy seas where the Kingstons were above the water line, the pipe to the expansion tank is exposed, but the water in the expansion tank maintains the header tank back pressure.


Is this a bad conclusion?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2016, 01:59
Hello Mr. Tore,


Does this rendition look OK?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2016, 02:43
Hello Mr. Tore,


I uploaded Skizzenbuch to dropbox with the updated version of page 83 on water compensating system and the selector valve.  When you have time would you please review page 83 and let me know in it is OK?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Dec , 2016, 03:25
Don.
In fuelconfiguration the expansion box act as a possible oilspill buffer in the safety (relief) pipe to the sea, trapping possible fuel contaminated compensating water allowing to settle for a later drainage. As for your theory of while surfaced exposing the Kingstons to the surface  in heavy wheather I guess it is a bit far fetched. A list exposing the Kingston to the surface would possibly cause battery acidspill and should be avoided and a possible short drainage of the headertank would not cause much of a trouble as surfaced you top up the tank by the dieselcoolingwater continuously. I guess you should only maintain the purpose of the expansion tank would be to prevent oilcontaminating of the compensating water to prevent possible oilspill regardless of the reason.
I discovered there is a text mistake in my sketch  comp. water selector valve: The violet fig. 1 is fuelconfiguration and 2 is the ballast configuration as corrected on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Dec , 2016, 03:30
Don, I Guess so but may be you should add the selector valve in ballast position as well.
Tore
Hello Mr. Tore,


Does this rendition look OK?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 19 Dec , 2016, 05:11
Hi Gentlemen,


because we do not have detailed documentation of the fuel compensating system, I have started searching any pieces of information related with this subject.
In the attached pdf file I have transcribed the description of the fueling process (in German). It is interesting itself, but also it can provide some clues regarding the fuel system. I did not translate it because I didn't want to make mis-interpretation. You can easily copy text and use some online translators. We can also discuss some parts of text here, on the forum.


I have also attached the drawing with the external fuel tanks and ballast/fuel tanks at the type IXC/40 U-Boat. In my opinion, especially interesting is the drawing of the fuel tank (Treibolbunker), whose piping is similar to the installation given by Tore. On the other side, the arrangement of the ballast/fuel tank (Tauchbunker) is simpler than the corresponding, hypothetical piping of the ballast/fuel tank at type VIIC U-Boat.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2016, 14:06
Hello Mr. Tore,


I believe I have missed something with regards to the selector valve...  Does the selector valve have the header tank as its source and distributes compensating water to the saddle tank or to the sea (My drawing)? Or is the expansion tank the source and it is switched between the header tank or to the sea (Your drawing)?


1. In the ballast configuration you are shutting off all compensating water flow and the results would be an overflow at the header tank.


2. When surfacing, the ballast is blown to a point with compressed air, and then the diesel exhaust completes the blowing process.  It looks like there is a possibility for the expansion tank to get blown as well?


I thought we originally wanted the compensating water either going to the saddle tanks or to the sea?


However, your selector valve configuration makes sense where the compensating water flow stops at the saddle tank in the RFO Configuration, and stops at the selector valve in the water ballast configuration. 


Which is correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Dec , 2016, 15:29
Don.
Your first question yes.
Your second question. As indicated on the image the pipe to the expansion box ends in the residue water in the ballasttank. When you are blowing the saddle ballasttank by exhaust you always look for the bubbles indicating the tank is empty. However you cannot empty the tank completly , there is always some residue water in the ballasttank as the Kingston opening is higher up than the end of the expansionbox pipe and as the pipe to the expansion box ends in this residuewater you would not exhaustblow the expansionbox. In ballast configuration the compesating watersystem is sealed off from the tank and is not involved in the ballast configuration.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2016, 16:16
Hello Mr. Tore,

Since Maciek has posted what looks to be a Type IX C/40 fuel oil tank (left) and ballast tank (right)...  Should we reconsider the connection between the venting pipe and the compensating water pipe coming from the expansion tank? I would think the German U-Boat engineers would keep the same concept for both U-Boats...

One thing to note*


1. IX C  fuel oil bunkers "a" could not be converted to a ballast tank
         tanks FBT 2, FBT 3, FBT 4, R1, FBT 6, and FBT 7 could be fuel oil or water ballast


2. IX C/40 fuel bunkers "1a and 2a" could not be converted to a ballast tank
             tanks FBT 3, FBT 4, R1, FBT 6, and FBT 7 could be fuel oil or water ballast


3. IX C/40 ballast tank design that could be converted to a fuel oil tank has the compensating water line going to the bottom of the tank, and the venting pipe 100 cm above the Kingston and no expansion tank.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2016, 21:50
Hello Mr. Tore,


Wow, I apologize for being such a difficult student...


1. When the saddle tank is in the ballast mode; we have the compensating water line going through the selector valve to the sea through the saddle tank.  Why do we need the line going through the saddle tank to the sea, the Kingstons are already open? It looks like we only need one water compensating line going into the saddle tank?


2. The expansion tank will capture fuel oil at the top during fueling.  As long as the fuel oil is not forced into into the lower pipe in the expansion tank, then that's not a problem. later the fuel oil in the expansion tank will be forced back into the saddle tank by compensating water when the fuel oil is transferred internally.


3. I think the expansion tank is exactly that... during a hot day the fuel oil will expand and apply pressure on the compensating water and the water in the lines may overflow at the header tank.  If the U-Boat dives to a depth where the sea water is much colder, then the fuel oil will condense and additional compensating water will enter the expansion tank from the header tank line. (Here in the US, they say to full up your auto tank in the morning - the gasoline is cooler, in the afternoon the gasoline is warmer and has expanded, so you get less for the dollar).


4. I have attached the drawing of the Type IX C/40 FBT selector valve, If it's the same valve in the Type VII C...  Can you describe how it works?

Maciek, thanks for the drawing...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Dec , 2016, 01:14

Q. 1. I guess you forgot the base for our assumptions which are confirmed German sources. Maciek quoted previously a German source: Je Sicherheitsrohr. Ist der Drueckwasserschalter zu, stelt das Drueckwasserrohr von restwasser der Tauchzelle ueber Drueckwasserschalter nach aussenbords das sicherheitsrohr dar.
Translated: Re safety pipe. If the selectorvalve is shut would the compensating pipe (in the tank) be connected via the selectorvalve to outboard ( the sea?) acting as a safety (relief) pipe. Hence to prevent venting, the outlet pipe takes the shortest way to the sea thru the tank as you would not have the pipe outside, .
Q.2. When the tank in the fuelconfiguration is recieving fuel, the compensatingwater is forced back via the selectorvalve to the headertank. As you know the filling of the tank is monitored by the check cocks above the compensating pipe end in the tank, particularly towards the end of the fuelling, which is stopped when fuel reach the testcock prior to the fuel reach the compensating watersystem ( expansionbox).
Q.3. If the tank is in fuelconfiguration, the expansion box is in contact with the sea via the headertank and the differential pressure sea/ tank at bottom of the tank would be equal to the weigth of the liquid (seawater) column up to the header tank. regardless the depth. The pressure in the expansionbox and tank might vary depending on the liquidcolumns temperature, salinity etc. but a differential pressure shall always persist.
Q.4. This icon of a selectorvalve is unknown to me, and is not shown on any VIIC plan. I am not familiar with the IXCs, but if you have a selector valve in the position shown on the IXC plan having the outlet to the sea, (outboard), on top of a ballasttank, the selectorvalve would act as a vent. Somehow this selectorvalve must prevent venting, I cannot tell how. In the VIIC system we have assumed a venting prevention by putting the outlet to the sea at the bottom of the tank mentioned above, not confirmed though. It could be worth while to check this item how it works as it would have been a better solution having the outlet under the casingdeck, avoiding the pipe thru the tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Dec , 2016, 12:52

Hi Gentlemen,

I have also attached the drawing with the external fuel tanks and ballast/fuel tanks at the type IXC/40 U-Boat. In my opinion, especially interesting is the drawing of the fuel tank (Treibolbunker), whose piping is similar to the installation given by Tore. On the other side, the arrangement of the ballast/fuel tank (Tauchbunker) is simpler than the corresponding, hypothetical piping of the ballast/fuel tank at type VIIC U-Boat.


To the drawing, I will add the related description from the Type IXC Design Study (http://www.uboatarchive.net/Design/DesignStudiesTypeIXC.htm):
Quote
A compensating water system is used with all fuel carrying tanks with the exception of the auxiliary tanks. Pressure on the compensating system is through the medium of a head box in the superstructure. The compensating lines to the individual fuel ballast tanks run directly to the bottom of the tank while the line for the outboard normal fuel tanks (my note: that is Treibölbunker a) leads into the small salt water niche (1.5% of fuel tank's volume) in the bottom of the tank; a line then leads from the top of the niche to the bottom of the fuel tank. [...]. Test piping with an overboard discharge leads from the bottom of all the normal fuel tanks, and from a point approximately 4 inches above the top of the flood opening on the fuel ballast tanks (my note: that is Tauchbunker). These test lines are normally used as salt water discharge lines when fueling - not only to indicate when the tank is filled with oil - but mainly to prevent possible contamination of the compensating water lines with fuel oil. All piping runs external to the pressure hull.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 20 Dec , 2016, 13:25
Q. 1. I guess you forgot the base for our assumptions which are confirmed German sources. Maciek qouted previously a German source: Je Sicherheitsrohr. Ist der Drueckwasserschalter zu, stelt das Drueckwasserrohr von restwasser der Tauchzelle ueber Drueckwasserschalter nach aussenbords das sicherheitsrohr dar.
Translated: Re safety pipe. If the selectorvalve is shut would the compensating pipe (in the tank) be connected via the selectorvalve to outboard ( the sea?) acting as a safety (relief) pipe. Hence to prevent venting, the outlet pipe takes the shortest way to the sea thru the tank as you would not have the pipe outside, .


These assumption are also confirmed by British report on HMS Graph (http://www.uboatarchive.net/U-570/U-570BritishReport.htm) (ex-U 570), quoted previously by Tore:
Quote
The compensating water pipes are led from the expansion tank (head tank in fact, my note) in the conning tower casing through double-seated valves to the small expansion tanks fitted at the bottoms of the fuel tanks. The double seated valves must be either in connection with the expansion tank (head tank in fact, my note) or with the sea. The expansion tank is always in open connection with the sea and thus the fuel tanks are always equalised and the only compensating water pressure which can be applied is that due to the head of water in the expansion tank (head tank in fact, my note). This arrangement is necessary where direct blows are fitted and avoids the possibility of straining the tanks due to high pressures.

and
Quote
The water passes down to the tank through a double-seated valve which admits water to the tank either from the expansion tank (head tank in fact, my note) or from the sea.


However British made some confusion, using the "expansion tank" term for the head tank in the conning tower as well as for expansion tank at the bottom of the fuel oil/ballast tank. I have made some annotations to point which tank is which.


Don, I would also think that German engineers would keep the same concept for both types of U-Boats, however there are clues that they wouldn't.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Dec , 2016, 18:54
Hello Mr. Tore and Maciek,


I would like this iteration of the expansion tank system to be the final change to Skizzenbuch on this subject.


1. I went back to Mr. Tore's latest drawing.
2. I re-drawn the selector valve in the Fuel Oil Mode and the Ballast Mode.
3. I got the expansion tank pipe below the Kingston's highest point (the pipe is always in the water).
4. In the Fuel Oil Mode the expansion tank is in connected to the header tank through the selector valve, and while submerges it is in contact to the sea at the header tank.
5. In the water Ballast Mode, I corrected the selector valve and Identified the Safety Pipe.


If I understand the function of the safety pipe in the Ballast mode; during a HP blow the ballast water is forced out though the open Kingstons, and into the expansion tank as well, and you don't want that thin metal tank damaged!  So the connection at the selector valve to the safety pipe which drains to the sea provides the means for pressure relief. Excessive pressure from the HP Blow forced water into the expansion tank through the compensating water outlet pipe (backwards water flow)...


Gentlemen, If anything is not correct; text or the drawing, then please let me know!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 21 Dec , 2016, 03:42
Hello friends.  Just wanted to leave a screenshot here of the game that we are building. Again, big thank you for all of you here for helping me to build this thing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2016, 05:41

Karel.
Amazing atmosphere. The handwheels of the exhaustblowing panel is a bit on the large side. When you are blowing the tanks by exhaustgas the tophatch is normally open and people are on the bridge. During daytime you`ll get a welcome faint glimse of daylight coming down to the hatch opening.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 21 Dec , 2016, 06:58
Thank you Tore.


Yes, we had to exaggerate a little bit because of today's state of technology. Having bigger handwheels makes it more comfortable for a person to grab this object with motion controllers and also helps keeping physics a bit more stable. Game engine physics tend to go nuts with these kinds of interactions. Just to give better context. The game is going to be played on this virtial reality device https://www.youtube.com/watch?v=qYfNzhLXYGc&t=135s (https://www.youtube.com/watch?v=qYfNzhLXYGc&t=135s)


As for daylight. This was another sacrifice we had to make. Virtiual reality game must run minimum at 90 frames per second in order to avoid jitter in the headset. This means that to keep the visual quality that we want, we have to cheat here and there. This includes all lighting which will be baked into the environment. This sadly means no realtime light, when i open the hatch i am not going to get sunlight. These are just sacrifices that we must take in order to make it able to run on current gaming PC. But years from now, down the road we can change all that when gaming PC will become more and more powerful.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2016, 07:35
Karel.
Interesting problems. Anyhow operating an Uboat in the artic would never offer a sunlight down the hatch, only dim daylight, but nevertheless highly appreciated after being days submerged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Dec , 2016, 08:24

Don.
I am afraid we have not yet achieved a complete confirmed arrangement of the saddle tank fuel arrangement. Maciek has provided a few interesting informations although I agree to his comments you cannot copy details from a IXC to a VIIC, I am tempted to discuss the details of the crosssection of the fuel/ballast arrangement on the imaged shown by Maciek. On the image below I have tried to show details which might be applicable for a VIIC.
The "oil drain" from the inverted U-tube might not go up to a drainvalve below the casing deck,  we have no german confirmation of such arrangement, I guess the arrangement with a small swan-neck shown on the IXC cross sectiondrawing is possibly an appropriate alternative, simple and reliable. The possible oilcontamination is lead by a small swan neck pipe from the  overflowpipe from the expansion box ascending and eventually  merge with the fuel in the tanktop. A fuelling check is done with the standard fuel checking.
The expansion box arrangement, light blue on the sketch, could very well be used on the VIIC saddletanks as it matches the written descriptions.
The selector valve arrangement is a puzzle as the icons on the systemplans are not identical, the IXC plans have obviously another selectorvalve design allowing the valve to act as relief valve without venting the tank thus avoiding the long pipe down the sea. Our latter pipe with sea outlet has yet to be confirmed for the VIICs.
Hopefully somebody might come up with some info/images allowing us to have a confirmed arrangement for your Skizzenbuch, until the our assumption remain unconfirmed assumptions. Sorry about that.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Dec , 2016, 14:51
Hello Mr. Tore,


I have been confused about the pipe going to the sea from the selector valve...  After Maciek came up with the type IX tank configuration, I created a drawing and then deleted it because of our further discussions. However, I went back to my MS trash basket and restored the image. 


This is the drawing... Do you think this could be the basis for a different approach?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 21 Dec , 2016, 17:03

Hi Karel,

Hello friends.  Just wanted to leave a screenshot here of the game that we are building. Again, big thank you for all of you here for helping me to build this thing.


Great work. However, if you want to model type VIIC U-Boat (not a museum boat in Laboe), you should pay attention to some modern modifications, for example the control room periscope. The current periscope in the U 995 control room is a post-war type ASR C/13 attack periscope, taken from U-Hai or U-Hecht.
And not only ocular box is replaced, whole tube, together with periscope head is from the attack periscope.
See the attached drawing.


The original ocular box can be visible on this photo (provided by Tore):
http://models.rokket.biz/index.php?topic=921.msg19664#msg19664




More details in this article (http://tvre.org/en/aiming-with-the-periscope).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Dec , 2016, 22:37
Hello Mr. Tore,


What do you think about this version of the saddle tank compensation system?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2016, 00:51
Don.
Some how I have trouble to post my mail, I`ll revert as soon as it is fixed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Dec , 2016, 01:43
Hello Mr. Tore,


Just an Idea...  After reading the U-570 Report several times; here is my idea...


1. It works OK in the Fuel Oil Configuration.
2. In the ballast Configuration the selector valve is open to the sea.  The valve is above sea level so the sea water only comes up to the sea level in the pipe in this mode.  When the U-Boat is submerged, the expansion tank is equalized through the open selector valve...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Dec , 2016, 03:02
Hello Mr. Tore,


This is the full detail drawing...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Dec , 2016, 16:18
Hello Mr. Tore,


additional drawing...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Dec , 2016, 04:25
Hello Mr. Tore,


When the ballast tanks are in the fuel oil configuration, would they open the residual valves for FBT2 to allow the pipe between the shut gate valves to flood?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2016, 07:32
Don.
I am happy being back.I am not sure I understand you idea 3 correctly. If you have an arrangement as on your sketch in ballast configuration having the ordinary double seated selector valve shut to the headertank and open to an outlet under the casing deck you are venting the tanks if the Kingstons are open. which means you are loosing almost 50M3 buoyancy and do not have sufficient surface draft. I agree you are in conformity with the text and documentation, but unfortunately with a lousy draft. Normally when you are operating an active submarine at sea you`ll have the Kingstons open and ready to dive.   The only time this would work is if the Kingston are shut thus the documentation should have mention these restrictions to my opinion. We have then to assume a remark to the design : the selectorvalve in ballastcondition can be open to the sea only when the Kingstons are shut thus acting as a safety/relief connection to the sea. I am still in doubt if that is the correct arangement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Dec , 2016, 07:50
Hello Mr. Tore,


When the ballast tanks are in the fuel oil configuration, would they open the residual valves for FBT2 to allow the pipe between the shut gate valves to flood?


Regards,
Don_
Don.
The residue venting of fuel/ ballasttanks 2 have  gatevalves pretty close to the ventpipe outlet from the tank. I assume these valves are shut in fuel configuration.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Dec , 2016, 20:15
Hello Mr. Tore,


Referring to the attached drawing...


1. In order to establish the final air pressure inside the saddle tanks while on the surface; The diesel exhaust blowing pressure is 0.5 atmospheres above atmospheric pressure of 1.0 atu. Therefore, the saddle tank internal air pressure will be 1.5 atu after the exhaust blowing.


2. The water level inside the saddle tanks will be just above the top of the Kingston ports; the saddle tank's Kingston valves are open to the sea while the U-Boat is on the surface or submerged (water ballast configuration).


3. The air in the saddle tanks will remain captured in the saddle tanks until the vent valves located at the top of the saddle tanks are opened, then and only then will water level rise inside the saddle tanks while the U-Boat is on the surface.


4. It is established that the compensating water outlet pipe is positioned near the very bottom of the saddle tank and well below the standing water level inside the saddle tank. So, there is no means for the ballast tank air to escape from the saddle tank unless the saddle tank is vented.


5. If we compare the water pressure from the surface to the water level at the bottom of the saddle tank where the Kingstons are open to the sea, and then to a point outside the ballast tank at the same water level; the water pressure would be exactly the same.


6. Therefore, the water level inside the compensation pipe going to the selector valve which is open to the atmosphere would be at the sea level.  This would be the water line established by the U-Boat's buoyancy (displacement) Vs the weight of the U-Boat.


This would be the same principle with the following test; if we took a water glass and drilled a hole through the bottom center and placed a straw through the hole until it lined up with the top edge of the glass, then we turn the water glass upside down and partially submerge it into a bath tub filled with water. The air in the glass would be slightly compressed as we forced the glass into the water, and the water level in the straw would match the water level in the bath tub. If we had a means of balancing the glass, then it's weight would establish the water line for the glass in the tub...


What do you think?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2016, 02:25
Don.
When the ballasttank is open to the sea, the seawaterlevel rises in the tank until the counterpressure of the air/exhaustgas is equal to that of the seapressure. When the system is in ballance,  the pressure is the buoyancy pressure. When the ordinary vents are opened, the pressure is released and air /exhaustgas escapes from the ballasttank, allowing the seawater filling the tank.
When the selector valve outlet is open to the air as in the proposed system, the deplacement pressure is released as for normal venting. The only difference is, as the pipe for the selector valve  ends in the tank residue water this water shall be forced out thru the selectorvalve outlet in stead of air/exhaustgas, followed by the seawater thru the Kingstons. When the water enters the tank it compresses  the air/gas on the top leaving a small volume air/ exhaustgas in the top of the tank having the ambient seapressure when the system is in ballance. This means that when you release the deplacement pressure in the ballasttank thru the selectorvalve with open kingstons, seawater is filling the tank and you loose you deplacement buoyancy. According to Archimedes you are sinking with a small volume of air/ gas compressed on the tanktop.  The only way to avoid this is to shut your kingstons which is not wise for an operational submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 03:17
Hello Mr. Tor,


If the expansion pipe outlet is below the water line in the saddle tank, the how can the tank vent through the selector valve to the atmosphere? There is NO path to vent the ballast tank???
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 03:28
Just like the Glass in the bath tub...  the air pressure in the glass has not escaped, so the water pressure will force the water up the straw until it matches the tub level...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 04:12
"When the selector valve outlet is open to the air as in the proposed system, the displacement pressure is released as for normal venting."

(1) The water from the sea through the open Kingstons goes up the pipe to sea level. The ambient pressure inside the saddle tank maintains the current water level in the ballast tank as set by the displacement Vs the weight of the U-Boat.


If the Kingstons were shut, then I would agree that the 1.5 Atu ambien air pressure would push the water up the pipe if the water column weight were less than the upward pressure differential.  However, in this instance the ballast tank is being vented, but the U-Boat still maintains the same water line because we have not changed displacement with the shut Kingstons.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 04:55
Hello Mr. Tor,


Would you please review the modified reply #3356


I'm staying up to work with you on this subject...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 06:09
Hello Mr. Tore,


Just for conversation...  Lets say we closer the selector valve.  Then we got a hose with a shut-off valve at one end, and place it at the deck height.


1. We then have a diver to take the other end of the hose down to the level of the internal compensating outlet pipe height. However, several feet away from the Kingston open port outside the U-Boat saddle tank.  then we open the hose valve. I believe the water will be forced up the hose to sea level. correct?


2. Now, we have the diver to take the hose right up next to the Kingston open port outside the U-Boat at the same height and perform the exact same experiment.  The results should be exactly the same. correct?


3. Finally, we have the diver to place the hose inside the ballast tank, and place it next to the compensating valve outlet. Then we open the hose valve and vent.  I believe the external water pressure will push the water up to sea level and stop, just like the other experiments.  The internal saddle tank air pressure of 1.5 atu has established the water level inside the saddle tank.  The venting hose is filled with water from below the saddle tanks internal water line, and that water came from the sea.


Where am I wrong with this logic?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2016, 06:10
Don.
1. When the selectorvalve is open to the air (sea) the seawater enters the saddletank thru the kingstons as the displacement pressure is released, the tank is no longer a buoyancy tank as no  counterpressure prevents the water to enter, if you put the selector outlet pipe down into the sea at the level of the kingstons you`ll have a counterpressure equal to the inletpressure and the system shall stabilize keeping the deplacementpressure and no air/ exhaustgas shall escape.
2 You assumption with shut Kingstons is correct appart from the 1,5 atu. The displacement pressure in the saddle tank would probably be less as the Kingston are about 2,2 meters below the sealevel at normal draft. The 1,5 atu is the limit for the exhaustgaspressure and relates to the mainengines backpressure limit rather than the saddletank deplacement pressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 06:24
The displacement pressure has established a water level in the saddle tank.  The compensating water outlet only sees the water pressure from the sea water below the ballast tank's established water level.  And this pressure is dependent on depth..
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2016, 06:32
Hello Mr. Tor,


If the expansion pipe outlet is below the water line in the saddle tank, the how can the tank vent through the selector valve to the atmosphere? There is NO path to vent the ballast tank???
If the tank has pressure, in this case deplacement pressure, this pressure forces the residue water thru the open selector valve, the air/gas remains on the top being compressed. As the residue water is drained the water entering the kingstons is partly following the residuewater up thru the selectoripe and overboard. The tankbuoyancy is gone and the submarine sits deeper in the water and eventually sinks (dives).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2016, 07:06
The displacement pressure has established a water level in the saddle tank.  The compensating water outlet only sees the water pressure from the sea water below the ballast tank's established water level.  And this pressure is dependent on depth..
Don, yes but when you release the displacement pressure via the selector valve there is no counter pressure and the water rises in the tank as you have lost the buoyancy. Loosing buoyancy means the boat sinks deeper and if all the saddletanks have lost their buoyancy it means you loose almost 50 tonnes. If you should do this operation on only one tank you create a surface list and upset the surface trim.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 07:49
Hello Mr. Tore,


The best way to show my point is with a drawing...


We have two drinking glasses forced into a pool of water where both drinking glasses are partially flooded (we now have compressed  air in the drinking glasses).  We put two (2) glass tube in the water with my finger over the top end of each tube; one outside the drinking glass on the left, and one inside the drinking glass on the right. 


Now, I allow the glass tubes to flood (this would be like opening the selector valve).  The results would be that both tubes would flood up to the pool's water level.  The water in the glass tubes came from the pool and there no connection or affect on the air pressure level inside either drinking glass air pressure area.


The water pool pressure acting inside both drinking glass enforces the water level in both scenario. Taking water from below the waterline in the drinking glass on the right changed nothing... With respect to the drinking glasses because the water came from the pool!


See my drawing!


When I inserted the two tubes into the pool of water, the pool's water level increased by the volume of both plugged water tubes. When I allowed the tubes to flood, then the pool water level decreased by the volume of water inside of both tubes. 

Basically, when the selector valve is opened in the U-Boat, the water is coming from the sea because of the open Kingstons.

The U-Boat is not going to decrease the sea's water level when opening the selector valve and allowing the selector pipe to flood...


I hope this all makes sense???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 11:24
Hello Mr. tore,


Please review my updated reply #3363


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Dec , 2016, 22:44
Merry Christmas to all, and to all a good night my friends...
Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Dec , 2016, 23:40
Don
The same to you and all our VIIC friends. My wife  and family think I am crazy sitting here with VIIC questions. Don I think your water glass gives a brilliant demonstration of the problem. Below I have modified your sketch a bit to demonstrate my thougths.
I guess the estimated deplacement pressure in the saddletank is appr. 0,22 atm. overpressure, which is appr. 2,2 m watercolumn. When you put a bended tube into the bottomwater in the tank leaving the other end of the tube in the atmosphere I guess the tankpressure push the water in the tube up to a pressure equilibrium when the watercolumn in the pipe is 2,2m above the sea surface, more or less as a watergauge where the watercolumn is showing the pressure in the tank.
If you place the selectorvalve at the top of the saddletank, I believe the outlet is less than 2,2 m above the seasurface. In that case the water in the tank is forced out of the tank allowing the seawater in thru the Kingstons.
May be this explains my theory a bit better.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Dec , 2016, 02:47
Don.
I guess I am going crazy ( just too old), my watergauge theory is all wrong, eliminating the pipe watercolumn in the sea. I must confess your system works and the matter is solved, thanks to your persistent stamina. The selectorvalve can have the outlet to the sea under the casingdeck and the outlet indicated on Simons image is most probably the selectorvalve outlets.
Sorry about the confusion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 25 Dec , 2016, 17:44
Tore, in the British Report on U-570 on page 36 on the H.P. Air Lines (http://www.uboatarchive.net/U-570/U-570BritishReport.htm (http://www.uboatarchive.net/U-570/U-570BritishReport.htm)). Do you think they still used copper on the late war U-Boats?

"2.  The working pressure is 205 atms. and the air line is made of copper, external diameter 11/16 in., internal diameter 7/17 in."
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Dec , 2016, 21:55
Hello Mr. Tore,


Not a problem as Maciek would say...  We all are getting older! However, I keep telling my wife Maureen that "I'm 17 going on 76"...  I just don't recognize that old person when I look into a mirror!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Dec , 2016, 12:13
(https://c6.staticflickr.com/1/533/31894640085_488dba5ef8_o.jpg)
This images has been resized. Click to view original image.

Hi Tore, Don & Maciek.

I know must of the openings above the exhaust maniford, but what is the Yellow opening?

White = Vent valves Opening - Main ballast/Reserve fuel oil tanks.
Orange = Main Exhaust Gas Blow Valve.
Green = HP air line.
Blue = Grease Distributors Opening.
Red = Exhaust Gas Flap Valve, Outboard Opening
Yellow = ??
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 26 Dec , 2016, 15:12

Hi Simon

I know must of the openings above the exhaust maniford, but what is the Yellow opening?

White = Vent valves Opening - Main ballast/Reserve fuel oil tanks.
Orange = Main Exhaust Gas Blow Valve.
Green = HP air line.
Blue = Grease Distributors Opening.
Red = Exhaust Gas Flap Valve, Outboard Opening
Yellow = ??


The yellow opening is the HP line hull valve for the air bank 2 (two flasks above the diesel engine assembly patch).
I'm not sure about green opening - the valve handle looks like the valve used in the oxygen installation.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Dec , 2016, 16:05
Hello Maciek and Simon,


White - Is this the beveled gear assembly that activates the dual vent valves above the pressure hull; the ones that vents the residual trapped air in the main ballast/reserve fuel oil tanks (FBT 2) port and starboard side?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 26 Dec , 2016, 16:10

Hi Don,

White - Is this the beveled gear assembly that activates the dual vent valves above the pressure hull; the ones that vents the residual trapped air in the main ballast/reserve fuel oil tanks (FBT 2) port and starboard side?


Right you are, Don!


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Dec , 2016, 16:29
Also here is a image of what I believe are the grease selectors in U-505 that didn't get covered with white paint like in U-995...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 26 Dec , 2016, 16:33

I know must of the openings above the exhaust maniford, but what is the Yellow opening?

White = Vent valves Opening - Main ballast/Reserve fuel oil tanks.
Orange = Main Exhaust Gas Blow Valve.
Green = HP air line.
Blue = Grease Distributors Opening.
Red = Exhaust Gas Flap Valve, Outboard Opening
Yellow = ??


The yellow opening is the HP line hull valve for the air bank 2 (two flasks above the diesel engine assembly patch).
I'm not sure about green opening - the valve handle looks like the valve used in the oxygen installation.


Regarding the green opening, I was not able to locate the similar valve at the port side - I'm almost sure there is only one valve.
Maybe it is the grease line for the FBT 2 residual air vent valve? Maybe the grease distributor nearby does not cover this one greasing point?
As far as I was able to trace both lines (from the unknown valve and grease distributor), they are going to grease hand-pump at the aft bulkhead of the diesel engine room.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 26 Dec , 2016, 20:03
Tore, we know that the Germans do not used Tab Washers on the internal pipe flanges bolts but used Tab Washers on all pipe flanges bolts that penetrated the pressure hull.

Do you think the Germans used Tab Washers on all the external pipe flanges outside the pressure hull or only on the pipe flanges that penetrated the pressure hull?
Simon.
I cannot remember for sure, but would be inclined to think they would use tabwashers or other locking devices on essential pipeflanges like fuel compensatingwater and ventducts.
Tore

and


Don.
From www. uboat archive.netU-570/British report.
Tore

Hi Don & Tore

I never thought about looking at this report for pipe dimensions. I have always estimated the pipe dimensions by plans and photographs. I was just flipping through the report and notice on page 40 "The diameter of the ventilation pipes leading into the ship from the conning tower fairwater is approximately 9 - 3/4"." which is 247 mm. I just checked my 3-D model and I had estimated this pipe dimensions as 246 mm :D Sorry about the inaccuracy of my model I will fixs this and will do better next time ;D ;D

This can give us confidence that we are heading in the right direction to workout how a U-boat works and is constructed!

 I found two more measurements in the report.
  • The diameter of the opening of the vent valves of Fuel-Ballast Tank No's 2 & 4, U-570 was 401 mm, I had estimated 385 mm (4% error).
  • The diameter of Engine air induction pipe on U-570 was 546 mm I had estimated at 502 mm (8% error).

Today I fix the Engine air induction pipe diameter from 502 mm to 546 mm. So I added the tabwashers today ;D ;D

(https://c1.staticflickr.com/1/758/31902588255_4306686b2e_o.png)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 27 Dec , 2016, 10:30

I know must of the openings above the exhaust maniford, but what is the Yellow opening?

White = Vent valves Opening - Main ballast/Reserve fuel oil tanks.
Orange = Main Exhaust Gas Blow Valve.
Green = HP air line.
Blue = Grease Distributors Opening.
Red = Exhaust Gas Flap Valve, Outboard Opening
Yellow = ??


The yellow opening is the HP line hull valve for the air bank 2 (two flasks above the diesel engine assembly patch).
I'm not sure about green opening - the valve handle looks like the valve used in the oxygen installation.


Regarding the green opening, I was not able to locate the similar valve at the port side - I'm almost sure there is only one valve.
Maybe it is the grease line for the FBT 2 residual air vent valve? Maybe the grease distributor nearby does not cover this one greasing point?
As far as I was able to trace both lines (from the unknown valve and grease distributor), they are going to grease hand-pump at the aft bulkhead of the diesel engine room.


--
Regards
Maciek

Thanks, Maciek.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Dec , 2016, 03:23

Simon.
Sorry I have been away during the xmas season and coming back I experienced my PC is not working properly. Anyhow I read your last question and shall try to sum up the answers as per my image below. As to the green valve it is obviously an oxygen valve, if you look at the oxygen plan you`ll see at the port aft end is a oxygenvalve marked off as an oxygen supply to " rescuedivers". I guess you shall find a similar installation in the aft controlroom stb side next to the aft hydraulic pump. In the engineroom the complete fillinggear is not shown, it could have been removed later. As the the system plan shows only the valve it could even possibly be that the complete installation was not installed originally, only the connection. I cannot remember this Equipment, and the manual do not mention any outboard connection at this point.
It might be I shall not be able to communicate for some days as my computer have to be checked and serviced,. it is still under guaranty.
Whishing everybody a happy New year and see you hopefully some time early next year!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 30 Dec , 2016, 08:19
Hi Tore,


it's good to hear from you again.


In my opinion, the valve in question can not be oxygen supply for the Drager rescue gears.
According to British Report on HMS Graph (http://www.uboatarchive.net/U-570/U-570BritishReport.htm): (page 35)
Quote
To supply the oxygen bottles contained in the German equivalent of D.S.E.A. sets.  This is fitted in the control room.
On the attached drawing I have marked the fitting for connecting the Drager sets and "d" valve (with red color).

There are three other valves marked with letter "d" (I have marked them with blue color), but they are for cutting-off the branching lines supplying the oxygen to ventilation intake duct.
In the Diesel engine room the valve "d" as well as pressure-gauges and regulating valves are located at the aft bulkhead, at stb side.
The oxygen lines are thinner than the line leading to the valve in question.


Moreover, the shape of the valve-handle cannot be used for determining the function of the valve: in diesel engine room, near the cooling water intake hull valves are similar valves (see attachment).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 01 Jan , 2017, 13:30
Re: Plate 13: Cooling-water system. http://www.uboatarchive.net/U-570/U-570Plate13.htm (http://www.uboatarchive.net/U-570/U-570Plate13.htm)

Valve 'o' - Drain valve should be on the bottom of the muffler?

Valve 'n' - Vent valve should be on the top of the muffler?

► Does anyone know what Valve 'n' - Vent valve look like?



Re: Plate 10: Fuel oil compensating system http://www.uboatarchive.net/U-570/U-570Plate10.htm (http://www.uboatarchive.net/U-570/U-570Plate10.htm)

► Does it matter where you take the hot water from the muffler for the Fuel Oil Compensating System?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Jan , 2017, 12:42
Tore & Don,

I think I found the expansion tank ;D

Couldn't the small round shape at the very bottom of the saddle tank which is also right next the compensating pipe and the kingstons be the expansion tank??

It has a smaller diameter pipe coming out of it (its been cut in half but you can see it above and heading forward to the compensating valve).

Images has been resized. Click to view original image

The last time I thought I’d found it, but this time I have really found it this time, the expansion tank  ;D ;D ;D

Checkout this video https://www.youtube.com/watch?v=lWXyNY_MHfo (https://www.youtube.com/watch?v=lWXyNY_MHfo)

At 1:35 the driver swim along the casting and we see the two MB & RFO 2 & 4 control arms.

At 1:42 you get a clear view of the expansion tank with the compensating pipe.

At 1:44 you get a great overview of the tank and pipe.

(https://c8.staticflickr.com/1/773/31248255263_2bbbe3d707_o.jpg)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jan , 2017, 13:06

Hi Simon,

Possibly the location of the drain valves "o" Vs. the vent valve "n" may have something to do with the temperature of the water in the muffler...  The hotter water will be on the top and the cooler water will be on the bottom.  That's my take on the valve locations, until Mr. Tore comments...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Jan , 2017, 15:03
I been checking more drive film.

Below is I believe the Fuel oil compensating system Pressure hull opening.

(https://c7.staticflickr.com/1/608/32156490246_8c6862c873_o.jpg)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Jan , 2017, 18:51
Hi Tore, Don & Maciek.

These are the best pictures of the Fuel oil compensating system & expansion tank, I have found so far.

(https://c3.staticflickr.com/1/734/32070927722_df6a421be9_o.jpg)
To see fill size click https://www.flickr.com/photos/57740585@N04/32070927722/in/album-72157657431277710/ (https://www.flickr.com/photos/57740585@N04/32070927722/in/album-72157657431277710/)

(https://c1.staticflickr.com/1/411/32181580976_14e2b9e1b5_o.jpg)
To see fill size click https://www.flickr.com/photos/57740585@N04/32181580976/in/album-72157657431277710/ (https://www.flickr.com/photos/57740585@N04/32181580976/in/album-72157657431277710/)

(https://c4.staticflickr.com/1/744/32100839051_61aaf6ef3a_o.jpg)
To see fill size click https://www.flickr.com/photos/57740585@N04/32100839051/in/dateposted-public/ (https://www.flickr.com/photos/57740585@N04/32100839051/in/dateposted-public/)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2017, 19:51
Hi Simon,


I have labeled items on one of your images as to what I believe they are...  I am not sure about the rectangular opening in the lower area of Regulating Tank 2? Just for my own knowledge - How do you upload a huge file to this website and display a smaller image?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 12 Jan , 2017, 03:43

Hi Don,

I have labeled items on one of your images as to what I believe they are...  I am not sure about the rectangular opening in the lower area of Regulating Tank 2?



The rectangular opening is the flood opening of the port negative buoyancy tank (Q-tank). See where it is located relative to the FuMO 30 antenna shaft. Both visible gears (you have marked one as FBT 4 flood valve and second as Q-tank flood valve) are in fact for the flood valves of the FBT 4 port.


Just for my own knowledge - How do you upload a huge file to this website and display a smaller image?


Simon is using external image hosting service (flickr.com), after uploading the image he places the url to image in the message text between [ url ] [ /url ] tags.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Jan , 2017, 11:23
How do you upload a huge file to this website and display a smaller image?

Don, you can see all my photo's and pictures here https://www.flickr.com/photos/57740585@N04/albums (https://www.flickr.com/photos/57740585@N04/albums)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jan , 2017, 15:50
Hi Maciek and Simon,


Two images attached...  The Q Tank section is very narrow and the Q Tank grill is square...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Jan , 2017, 01:00
Hi Don,

Two images attached...  The Q Tank section is very narrow and the Q Tank grill is square...

Indeed, U996 has square grill, however it can not mean anything, the grill shape could depend on the yard.
Look at the position of the radar antenna shaft and Q-tank position, they are almost at the same height.
Moreover, the driving shaft for the FBT is mounted horizontally, while for Q-Tank - aslant.

Look at the plating of the U 995 tanks. In the area of FBT you can see dented plates (because this tank is
not pressure-proof), while in the are of Q-tank (and regulating tanks) the plates are intact (because these
tanks are pressure-proof). Similarly with the wreck of U 352. I guess that we can look at the FBT interior now
because non-pressure-proof plating corroded, while the adjoining Q-tank is intact.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Jan , 2017, 10:52
Look at the plating of the U 995 tanks. In the area of FBT you can see dented plates (because this tank is
not pressure-proof), while in the are of Q-tank (and regulating tanks) the plates are intact (because these
tanks are pressure-proof). Similarly with the wreck of U 352. I guess that we can look at the FBT interior now
because non-pressure-proof plating corroded, while the adjoining Q-tank is intact.

Maciek, do you think the plating thickness is different between the two tanks?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Jan , 2017, 11:36

Hi Simon,

Look at the plating of the U 995 tanks. In the area of FBT you can see dented plates (because this tank is
not pressure-proof), while in the are of Q-tank (and regulating tanks) the plates are intact (because these
tanks are pressure-proof). Similarly with the wreck of U 352. I guess that we can look at the FBT interior now
because non-pressure-proof plating corroded, while the adjoining Q-tank is intact.

Maciek, do you think the plating thickness is different between the two tanks?


Yes, I'm sure that pressure-proof tanks plating was thicker than the non-pressure-proof tanks and outer shell plating.
Apart from the notes from the post above, I have the quotation from type IXC Design Study (http://www.uboatarchive.net/Design/DesignStudiesTypeIXC.htm):
Quote
Outer shell plating is steel 42 (60000 psi tensile) specification KM 9104, except in the way of the variable tanks and negative tanks, which are specified to be of steel 52, (74000 psi tensile) specification KM 9104
The term variable tanks mean regulating tanks, and the term negative tanks mean Q-tanks.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jan , 2017, 19:08
Hello Maciek and Simon,


Maciek is 100% correct about the different thickness of sheet metal on the saddle tanks:
1. R1, R2, and Q Tank outter sheet metal is 11.5 mm thick
2. FBT 2 and FBT 4 outter sheet metal is 6 mm thick
3. The internal walls of Q Tank are 13 mm thick


However, let's examine the sunken Type VII U-Boat in question...
1. I would say the missing sheet metal cover on the port side of FBT 4 and Q Tank was the result of a depth explosion and not the effects of salt water corrosion over time. The reason for my conclusion is there are no internal support structures; they seem to be torn-off from the pressure hull and saddle tank.
2. If you look aft, the saddle tank FBT 2 port side, it looks to be intact.
3. If you look at the attached drawing, Q Tank was designed to withstand internal pressure because of the aft concave and forward convex sides.
4. When the depth charge detonated; the port FBT 4 was ripped open and the forward wall of the Q Tank was designed for the opposite stress forces.  Therefore, the port Q Tank was ripped open and exposed the mushroom valve actuating mechanism.  Q Tank has 1 internal rib type support structure mid  way in the tank, but I highly doubt that it would hold under such devastating pressure.
5. I conclude that both FBT 4 and Q-Tank on the port side were completely blown apart and the complete devastation stopped at the aft Q Tank internal wall which was designed to withstand a force in that direction.


Now as to that rectangle hole in question - I don't know? Did I go wrong on my conclusions as to what we see on this sunken U-Boat? Please advise...


Regards,
Don

PS - after looking at mt trusty steel ruler with inches on one side and mm on the other side; we're not talking about sheet metal. The 6 mm plate steel for FBT 2 and FBT 4 is a little under a 1/4 inch, and the 11.5 mm plate steel for R1, R2, and Q Tank is a little over 7/8 inch steel.  This plating would have to be rolled to fit the framing.  You are not going to bend that into place...
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 00:33
Hi,


maybe my plating consideration were going to far, however there are still issues of the flooding valves driving shafts orientation (which is horizontal for FBT 4) and their location relative to the conning tower (radar antena shaft).
In my opinion, the rectangular opening is located exactly where Q-tank is located.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jan , 2017, 00:44
After doing a map of the damage...  It looks like FBT 4 and Q Tank on the port side was completely blown apart when a depth charge detonated very close and  below the open Kingstons on the port side and through the metal grill leading to and protecting Q Tank.  The internal force blew the welded seams on FBT 4 and collapsed both the forward and aft walls of Q tank.  It looks like the destruction went in as far as one vertical frame structure into R 2.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 02:36
Don,


on the wreck photo (in this post (http://models.rokket.biz/index.php?topic=921.msg20064#msg20064)) with dashed line I have marked (approximately) the frame going through the Q-tank (which also crosses the radar antena shaft).
If the Q-tank was much forward and was blown away as you said, it had to be at the height of forward periscope (and this is not possible).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 02:44

Don,

After doing a map of the damage...  It looks like FBT 4 and Q Tank on the port side was completely blown apart when a depth charge detonated very close and  below the open Kingstons on the port side and through the metal grill leading to and protecting Q Tank.  The internal force blew the welded seams on FBT 4 and collapsed both the forward and aft walls of Q tank.  It looks like the destruction went in as far as one vertical frame structure into R 2.


On your map of the damage, the four flood valves are operated by two driving shafts (valve mechanisms), that is two flaps are operated by one shaft and the other two are operated by second shaft.
On your map you have marked one mechanism for all four flaps.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jan , 2017, 02:49
Hi Maciek,


I know that I am only guessing at this point... But since the destruction is into R 2 (I think?), then could that rectangular opening (if it is within R 2) be an inspection plate to permit servicing the Emergency Shut-Off Valve for venting MBT 3 within the air shaft? If you examine the previous image of U-995, they have a huge steel plate welded on what looks to be the outside area of this section...


I believe there would need to be a service plate to permit access for repairs to a damaged Emergency Shut-Off valve when in dry dock in a U-Boat pen...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jan , 2017, 03:00
Hello Maciek,


Now I have a real problem...  In my Skizzernbuch page 335 I have images of the drive shafts for the Saddle tank Kingstons and there is only one drive shaft for each tank (photos) of U-995... Am I wrong?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 03:07

Don,


the venting shaft of the MBT 3 is located behind the attack periscope and behind the conning tower. I have marked its approximately location on attached drawing (with green color).


However, I think you have right regarding the access opening to the emergency vent valve. I have found the photo (the shot from the movie (https://youtu.be/lWXyNY_MHfo?t=1m26s)) from opposite direction, when something like rectangular cover is visible (see attachment). If this is the access opening in the regulating tank, then the next rectangular hole is the flood valve of the Q-tank.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jan , 2017, 03:11
Hi Maciek,


I only see one shaft in the control room...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 03:17
Now I have a real problem...  In my Skizzernbuch page 335 I have images of the drive shafts for the Saddle tank Kingstons and there is only one drive shaft for each tank (photos) of U-995... Am I wrong?


See attached photos.


In the U-boat Information for U-boat Type VIIC (http://www.uboatarchive.net/Manual/Manual.htm) you can read:
Quote
For Flood valves for main ballast and reserve fuel oil tank 4 stb. and port   4

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Jan , 2017, 03:27
The second pair (first pair you have located correctly in petty officers room) of the shafts for FBT 2 flooding valves is located in galley. See attachments.
The third photo presents red linking shaft (at the right edge of photo) going through the WC cabin.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Jan , 2017, 11:49

Maciek is 100% correct about the different thickness of sheet metal on the saddle tanks:
1. R1, R2, and Q Tank outter sheet metal is 11.5 mm thick
2. FBT 2 and FBT 4 outter sheet metal is 6 mm thick
3. The internal walls of Q Tank are 13 mm thick

PS - after looking at mt trusty steel ruler with inches on one side and mm on the other side; we're not talking about sheet metal. The 6 mm plate steel for FBT 2 and FBT 4 is a little under a 1/4 inch, and the 11.5 mm plate steel for R1, R2, and Q Tank is a little over 7/8 inch steel.  This plating would have to be rolled to fit the framing.  You are not going to bend that into place...
 

I not see this drawing before, but you know if you look at this drawing, you can see all four expansion tanks for the Fuel oil compensating system marked on it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Jan , 2017, 11:54
If you download this picture of U-352, you can coun the framing very easy.

The damage look to me to start at No. 57

http://www.olympusdiving.com/wp-content/gallery/U352-Breakout-Gallery/U352_19border_copy.JPG (http://www.olympusdiving.com/wp-content/gallery/U352-Breakout-Gallery/U352_19border_copy.JPG)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Jan , 2017, 12:26
Hi Don & Maciek

I am trying to model the top of the CT, do you guys have any good photo's?

(https://c1.staticflickr.com/1/557/32158505802_6b66d5b999_o.png)
This images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/543/31466282644_3a36400370_o.png)
This images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/490/32268711236_99501ed7a8_o.png)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jan , 2017, 00:02
Hello Mr. Tore and Maciek,


Wow! I had it completely wrong in Skizzenbuch about the design of the drive shaft mechanism for FBT 2 and FBT 4.  I just ran into this misunderstanding on my part yesterday when discussing the sunken U-Boat with Maciek.  That 2nd screw jack mechanism led me to believe that Q Tank was blown apart. I didn't know that there was two (2) screw jack mechanisms in each saddle tank blister (FBT 2 and FBT 4, Port and Starboard).  I sure hope I don't have anymore of these lightning strikes...


Simon,


I have photos in books showing the tower in detail at the factory when being built.  After I get Skizzenbuck straightened out, I will copy the photos and email them to you...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jan , 2017, 01:57
Hello Mr. Tore and Maciek,


I have corrected Skizzenbuch to reflect the correct information about the number of drive mechanisms for FBT 2 and FBT 4.  Would you all please review pages 334 and 335 and let me know if anything needs corrected or changed in any way?


The new file Skizzenbuch 11 x 17 - M + Index.pdf in in my dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 16 Jan , 2017, 01:43
Hi Don,

I have corrected Skizzenbuch to reflect the correct information about the number of drive mechanisms for FBT 2 and FBT 4.  Would you all please review pages 334 and 335 and let me know if anything needs corrected or changed in any way?

I would change the sentence in bold.

Quote
The Type VII C U-Boat schematic below has the port Kingston Flap valves highlighted to show their location within the lower section of the saddle tanks for FBT 2 and FBT 4. Of course, there will be similar Kingston flap valves on the starboard saddle tanks. The four (4) individual Kingston flap valves are controlled (open or shut) by two (2) removable hand crank that attach to the drive shaft which passes through the pressure hull and engages the screw jack mechanism for each of the four (4) tank (FBT 2 and FBT 4, port and starboard). The locations of the drive shafts are designated by numbers 1 through 8 in the schematic. The mechanical diagram to the left shows the hand crank attached to the Kingston drive shaft which turns the screw jack external to the pressure hull, but within the saddle tank structure. The saddle tank Kingston flap valves open inward and swing from the bottom of the flap. The image of U-995 shows two (2) of the Kingston flap valves highlighted in YELLOW, and the protective grill for the Q Tank mushroom valve to the right. It may be difficult to read the numbers, but the saddle tanks have two different metal cover plating thicknesses; FBT 2 and FBT 4 have 6 mm thick outer plating, while R1, R2, and Q Tank have 11.5 mm thick plating because they are pressurized.

Maybe something like this:

The four (4) individual Kingston flap valves are controlled (open or shut) by two (2) removable hand crank that are attached to two (2) drive shafts which passes through the pressure hull and engage two (2) screw jack mechanisms (one for mechanism for two (2) flaps, two mechanisms for four (4) flaps).


The label at the bottom of the drawing:
Quote
Drive Shafts for the Kingston Flood Valves (2 per shaft)

Drive Shafts for the Kingston Flood Valves (2 flood valves per shaft)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jan , 2017, 02:12
Hi Maciek,


I will make the changes as suggested...


U-352 Q Tank grill is correct; only half was blown away...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jan , 2017, 19:44
Hello Mr. Tore, Maciek and All,


I updated the the image of the saddle tank/expansion tank on page 83 after viewing the photos that Simon posted.  I believe the current version better reflects the actual design (drawing attached).


Thank you Simon...


Maciek, I made the text changes to page 334 and the image change.  I did a little re-wording and made the long sentence into two shorter ones and eliminated all the brackets.


Let me know if it's OK...



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 17 Jan , 2017, 02:59
Hi Don,


now it looks good to me.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 17 Jan , 2017, 12:35
Simon,


I have photos in books showing the tower in detail at the factory when being built.  After I get Skizzenbuck straightened out, I will copy the photos and email them to you...


Regards,
Don_

Don, here the update top of the CT.

(https://c1.staticflickr.com/1/268/31994481200_c75fc70ff2_o.png)

(https://c1.staticflickr.com/1/667/32221409402_b4b98da526_o.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Jan , 2017, 14:39
Port Side Main Exhaust Valve

For the last several weeks I’ve been working on the exhaust valve, and for the first time I feel like I’ve made some significant improvements on the section of the U-boat. The drawings below are based on U-352 and are as accurate as I can make them base on the imaging of this boat. There are still details that are missing that I will have to guess.

I have also modelled all the internal structure, or was much as I can :D

Detail that I’m missing or cannot find are:

(https://c1.staticflickr.com/1/456/32467432645_1366e8e18b_o.png)
Fig. 1. Looking Inboard, to the stern.

(https://c1.staticflickr.com/1/596/31624000324_42c7227ecc_o.png)
Fig. 2. Looking Inboard, to the bow.

(https://c1.staticflickr.com/1/716/31655715003_ac5eb1d185_o.png)
Fig. 3. Looking outboard, to the stern.

(https://c1.staticflickr.com/1/754/32089181020_e7ff041306_o.png)
Fig. 4. Top.

(https://c1.staticflickr.com/1/638/32427118946_8e4512cee2_o.png)
Fig. 5. Looking to the stern.

(https://c1.staticflickr.com/1/453/31623972194_9a0716f36b_o.png)
Fig. 6. Looking outborad.

(https://c1.staticflickr.com/1/391/31655708033_955c3ceda6_o.png)
Fig. 7. Looking inborad.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Jan , 2017, 14:43
Cross-section Views

(https://c1.staticflickr.com/1/759/31655697313_46f1bb2675_o.png)

(https://c1.staticflickr.com/1/544/31655699993_3c705750e7_o.png)

(https://c1.staticflickr.com/1/580/31655701993_75767a2da0_o.png)

As always all can be resized, by clicking on the original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Jan , 2017, 00:39
(https://c1.staticflickr.com/1/580/31655701993_75767a2da0_o.png)

Don, Tore & Maciek.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jan , 2017, 20:38
Hi Simon,


This is what I have in Skizzenbuch from Mr. Tore...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 27 Jan , 2017, 12:07
Hi Tores,

Do you have any knowledge about how to obtain/compute firing solution information?  I am trying to use the RAOBF (range and angle on bow finder) and other tools playing the Silent Hunter 5 simulator on 100% realism.  I'm am finding the finding of target speed, range, and AoB tricky.

Generally I opt for 90-degree approaches so that range is irrelevant.  I use a "fixed wire" method to compute speed by adjusting my heading to match target bearing (0 degree bearing) and then use the stopwatch to measure how long it takes the target to traverse the vertical reticle in seconds.  If I know the ship length from the recognition manual I can then calculate target speed.

How did you guys come up with the target information?

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Jan , 2017, 12:18
Hi Steve,


for historical methods of determining target data check this site:
http://tvre.org/en/acquiring-torpedo-firing-data


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Jan , 2017, 16:33
Hello Mr. Tore and All,


Tuesday morning my Post Leather Bound First issue of Skizzenbuch was delivered to my doorstep via UPS. There was a litter inside the box taped to the binder stating that Schiffer Publishing LLC has decided not to publish the book. After a year and a half, now 2 months before the release date they canceled the book! They say the niche market is too small at this time.


To say the least; I'm a little %$*&T#, and I'll have to think about the situation...


Don_   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 29 Jan , 2017, 14:22
Hello Don,

Really sorry to hear this news, Don, this must be intensely frustrating for you. I'm hoping another publisher picks it up at some point. Keep your chin up if you can.

Best regards,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jan , 2017, 20:25

Hi Dougie,


Thanks for the encouragement...  I tried several other publishers and I get the same old line; too much cost to publish the book with the current readership base.  It looks like the book publishing market is shrinking each year because of printing costs and the availability of e-books.


However, the e-book readers have limitations to the document's format. I looked into Skizzenbuch in a e-book format, but none have that capability. Besides, every e-book device is dependent upon the sponsor and have a different format. I am thinking seriously about applying for a publishing company LLC here in the state of Georgia. I could then create a named publishing company and distribute a CD/DVD with a PDF book format and sell them on Amazon.


I am looking into PDF protection software where the file can not be copied from the CD/DVD, but I am considering the option of allowing the customer to print the file. I have a second Skizzenbuch book on the Type IX C & C/40 in the pipeline with over 100 pages completed. 


AS you can see, I have a lot of options to consider.  I could chuck it all and have my Skizzenbuch: U-Boat Type VII C Project with its leather post binder in my personal library, and create the 2nd book for my library as well...  Either way; I am very content!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 30 Jan , 2017, 06:03
 :(


Oh no. So sorry to hear about that. I was really looking forward for the release of Skizzenbuch since it contains valuable information for my game development efforts.
Hang tight Don Prince. I am sure that you will find an acceptable solution for your publishing problems. This unique historical knowledge needs to exists. I have wasted hundreds of dollars on various u-boat books that all contain the same generic information.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jan , 2017, 06:45
My PC crashed three weeks ago leaving me out of touch with my mailbox which has been very frustrating and I am truly sorry not having been able to participate in the discussions and able to answer the questions put forward. However I got my PC back this week and used a few hours to  get updated. Don, I regret very much that your Skizzenbuch has been rejected, so many hours of your enthusiastic work not to be published. However a substantial part of the work is available on this thread, hopefully for some use of the many interested enthusisasts.
Again sorry for my absence.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 30 Jan , 2017, 13:12
Hi Don,

There are some really average U-boat books out there, with some authors unable to tell the difference between a VIIC and an IX. So it gets really frustrating when properly researched material such as yours is prevented from book format simply due to financial reasons. I think I am going to have the same problem when I finish my U 47 book - the 200k+ word count and over a hundred images and drawings will not find favour with many publishers. So I guess I will be in the same boat as you.

The medium - whether printed book, E-book download or CD - is not as important as getting your research to be appreciated by enthusiasts. The CD via Amazon should accomplish this. It would also allow you to make updates as required and keep full control.  The only issue with the CD is that someone might try to rip it off and pass the files off as their own so the protection software for the pdfs sounds essential. 

Cheers,

Dougie

 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jan , 2017, 19:54
Hi Dougie,


If I decide to go ahead and publish Skizzenbuch, then I will do the following:



1. I plan to purchase the "CopySafe PDF Converter" application which is to prevent copying anything from the original PDF file and changing its contents. I plan on embedding the CopySafe Reader into the encrypted Skizzenbuch distributed document. You can copy the encrypted file, but that's it...


2. I will create "Kristall-Klare Publishing, LLC.  This will be done in the State of Georgia.  The LLC protects the single owner in legal matters. The only assets at stake are the publishing company assets.


3. Each PDF book published will have a US eBook Copyright.


I am seriously thinking about making this happen...


Dougie - some advice on publishing your book about your U-47. 


1. Keep the book in a standard format - publishers don't like to work too hard!
2. Keep a limit on the number of font sizes (preferably 2).
3. The legal stuff will drive a sane person crazy! - publishers want the profits, but won't legally have your back!
4. Your royalties (a low percentage) will be on the wholesale set price, not the retail price.
5. A PDF file may not be accepted by your publisher depending on their staff size. I had to create a TEXT File that had embedded print commands; <Insert image ###, Size, Location> / <TEXT: size, bold> / etc. All your drawings and photos must be in a separate folder and numbered to match the text file, or it could be something completely different.


I guess I may come off as a bit jaded (I hope not).  Best of luck my friend...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 31 Jan , 2017, 01:08
Hi Don,

I'm also really sorry to hear that your publisher cancelled publishing your book.
This book is one of the few that really introduces something new into the topic
of U-Boat technology. I hope that you find another way of publishing your work.

Tore, I'm happy to hear from you again.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 31 Jan , 2017, 11:45
Hi Don,

Thanks for your advice, I will have to make some adjustments as per your point 5.

When you are really to sell please let us know and we can put a link on the AMP website towards the CD.

Cheers,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2017, 16:35
Hi All,
 
I am looking that the internal framing of the saddle tanks, and it looks like that the Germans changed the design of the internal spars sometime during the war. The ‘late war’ design looks more simpler and stronger than that early drawings from 1940.

Has anybody come across this before or can confirm the change in the design for me?

Thanks, Simon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2017, 17:08
Hello Mr. Tore and All,


Tuesday morning my Post Leather Bound First issue of Skizzenbuch was delivered to my doorstep via UPS. There was a litter inside the box taped to the binder stating that Schiffer Publishing LLC has decided not to publish the book. After a year and a half, now 2 months before the release date they canceled the book! They say the niche market is too small at this time.


To say the least; I'm a little %$*&T#, and I'll have to think about the situation...


Don_


Don, sorry about the late reply, I have had my head down working on the saddle tanks (have already spent over 60 hours working on them already). Sorry to hear about your Skizzenbuch. I think it’s the way of the modern world that books etc. are becoming more digital.

Perhaps using a PDF could have some benefit as you could embed multimedia into the file, to better illustrate your point of view or what you are explaining (e.g. 3-D imaging, sounds, animations, overlays/ multi layered pictures, Spreadsheets).


I think I am going to have the same problem when I finish my U 47 book - the 200k+ word count and over a hundred images and drawings will not find favour with many publishers. So I guess I will be in the same boat as you. 

Dougie, a pdf could be great option for your book, as you could link pictures directly to the text and add animation (e.g. the path Prien took etc.).


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Feb , 2017, 20:41
Tore, Don & Maciek.

What is the smaller tank within the Regulating Tank 2, is it part of the Fuel oil compensating system?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2017, 00:03
Simon.
The rectangular drawn inside the regulating tank2 port and stb is a crossection of the venting duct from MBT 3 port and stb. passing through the regulatingtank 2 to the main vent boxes on top of the pressurehull as tried to show on my image below. The regulating tanks 2 port and stb have no connections to the fuel compensating system as they are only used as regulating tanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2017, 00:23
Simon.
The rectangular drawn inside the regulating tank2 port and stb is a crossection of the venting duct from MBT 3 port and stb. passing through the regulatingtank 2 to the main vent boxes on top of the pressurehull as tried to show on my image below. The regulating tanks 2 port and stb have no connections to the fuel compensating system as they are only used as regulating tanks.
Tore

Thanks Tore.

I just got a email from a friend that translated for me 'Luftschacht'  = 'Ventilation shaft'   :D

Two questions:
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2017, 00:36
I might be a little confused, so it vents from MBT 3 tank?

Tore, Don't worry about me just got a little confused, for some reason I was thinking it was venting the saddle tank not from MBT 3  :-[ :-[ :-[
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2017, 00:54
Tore, Don & Maciek,

Anybody has any idea about the size of the emergency shut-off valves for MBT 3?

Thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Feb , 2017, 02:05
Simon.
My guestimate would be 600mm x 450mm.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 07 Feb , 2017, 17:19
Simon.
My guestimate would be 600mm x 450mm.
Tore

Thanks, Tore.

This could be very close was there only about 555 mm between the frames.

Is could be the opening (forward Pressure Hull section)
(https://c1.staticflickr.com/1/568/32731892656_c3203ccec9_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2017, 00:37
Interior framing for the MBT 3

(https://c1.staticflickr.com/1/511/32737244176_b338e20ff5_o.png)
This images has been resized. Click to view original image.

(https://c1.staticflickr.com/1/585/32397848770_5a65789ebb_o.png)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 08 Feb , 2017, 02:58
@Simon.Your work is amazing, i understand that this takes years to be finished but storing this historically accurate information in this way is super amazing. The educational value of this will be tremendous. Also noted your feedback about my game periscope. Luckily in our case we are not building an exact historical replica since people will be playing this while wearing VR goggles. We have to make many modifications to accommodate their comfort levels and interactions.

Also i hope that it is ok to post it here. Our submarine game got featured in UploadVR. There is also a little video there. What makes me especially happy that it has even gained attention from people who were not previously interested in submarines. http://uploadvr.com/atlantic-ghost-submarine/ (http://uploadvr.com/atlantic-ghost-submarine/)

@Don Prince
I was thinking about your Skizzenbuch situation. It is not much but i can offer to recreate a virtual prop version of your book and place it inside the sub. It would fit into game narrative since our main protagonist is not part of uboat crew and has a valid reason for owning that book. I know that it is far from having it out in real life but who knows, maybe in future it will prove as an useful item for "marketing purposes" if you do find a solution to your publishing problem.

Karel
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Feb , 2017, 06:37
Simon.
I guess you got the idea
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2017, 11:32
@Simon.Your work is amazing, i understand that this takes years to be finished but storing this historically accurate information in this way is super amazing. The educational value of this will be tremendous. Also noted your feedback about my game periscope. Luckily in our case we are not building an exact historical replica since people will be playing this while wearing VR goggles. We have to make many modifications to accommodate their comfort levels and interactions.

Karel, how many poly can you push through the VR gear?

My model is now around 8 million poly ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 08 Feb , 2017, 18:52
The bulkhead between Reg tank 2 and Neg Buoy tank. How did they curve the bulkhead?

(https://c1.staticflickr.com/1/684/32412594570_f371a24462_o.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2017, 00:18

Simon.
I don`t think it is only the bulkhead between regulating tanks 2 and the neg. buoyancy (Q)tank which is curved. In fact regulating/ fuel tank 1, regulating tanks 2 and the Q tank have all curved bulkheads as they are pressureproof. As the differential pressures between these tanks might vary considerably depending on their independent operation, the separation bulkheads have to be curved to resist the pressuredifferential. In spite of that, the regulating tanks have differential manometers indicating the differential pressure enabling a monitoring that the max differential pressures are not exceeding the max. allowable values.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 09 Feb , 2017, 00:32

Simon.
I don`t think it is only the bulkhead between regulating tanks 2 and the neg. buoyancy (Q)tank which is curved. In fact regulating/ fuel tank 1, regulating tanks 2 and the Q tank have all curved bulkheads as they are pressureproof. As the differential pressures between these tanks might vary considerably depending on their independent operation, the separation bulkheads have to be curved to resist the pressuredifferential. In spite of that, the tanks have differential manometers indicating the differential pressure enabling a monitoring that the max differential pressures are not exceeding the max. allowable values.
Tore

Thanks, Tore.

Just finish the other side of the Q tank, next the regulating/ fuel tank bulkhead 1  :)  It take me a while to model each frame within the saddle tank as each one is totaly different :(

One thing that is worrying, on the plan you used there are three (4 four in total) additional supports that run horizontally that look ‘C’ shape from above. However on the more detailed plans there is only one of these horizontal spar :o

You might find it interesting, the thickness of the steel for each bulkhead is 13 mm.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Feb , 2017, 01:21
Hi Simon,


Only one "C" shaped support seems to make sense... The steel plate thickness of the exterior metal plating is 11.5 mm for R1, R2, and Q Tank (.45 inch). If the internal longitudinal supports, and the internal bulkheads were the same thickness as the outer plating, then all would have to be formed at a steel pressing plant and be assembles/welded together on site.


The saddle tanks FTB2 and FTB4 were 6 mm thick (.23 inch) for the outer shell. 


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Feb , 2017, 01:28
Simon.
A possible better image of the extra strengthening of the regulating/fueltank 1 and regulating tank 2 bulkheads belows shows there are only one bulkhead strengthening on each of the reguator/ fuel tank 1 and regulatore tank 2, hence in total of only three bulkheads. I guess these bulkheads were susceptible to damages hence extra strengthening. As far as I remember (vaguely) U 926 ( Our KNM Kya) had some signs of damage in this area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Feb , 2017, 01:39
Hi Simon,


One image shows the air shaft and the other image shows a different cutout of the ribs ((I guess for RFO 4).


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Feb , 2017, 22:05
Hello Mr. Tore,


I have a question about the Lubricating oil flow for either the GW or MANN engines?


On each side valve e1 selects the oil return tank port or Starboard, but the port diesel engine's oil pump only draws oil from the port side and it's the same for the starboard pump and diesel engine on the starboard side. I don't understand the reasoning behind this setup.  You could drain one tank and overflow the other tank with a non selective source and a selective return???

Also, I see no means to get the dirty oil into the dirty oil tank?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Feb , 2017, 02:59


Don.
The return of the lubeoil can be selected to either of the luboil system tanks (port or starboard). In the case of contamination, mostly seawater, you are able to isolate and clean the contaminated oil. This system is based on a lubeoil sentrifuge cleaning system which was removed on the later VIICs. However you are  able to draw lubeoil from either of the system tanks by using the fueltransfer pump as a spare lubeoilpump as indicated on my image below.
The original sentrifuge system  had two pumps, one for dirty lubeoil from the  system tanks to the sentrifuge and one for supply of clean oil from the sentrifuge to the systemtanks. On the later arrangement the sentrifuge installation was removed and a larger filter installed in the system eleminating the sentrifuges and pumps, I don`t have a systemsketch of the latter system. On the aft engineroom bulkhead is  a handpump which enables emptying the contaminated oil from either of the systemtanks including dirty oiltank to overboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 11 Feb , 2017, 16:34
Tore, Don, & Maciek.

Q. Would there be a wire mesh over the opening for the MB3 valve? (I just noted there a dotted line above the opening of the MB & RTO Tank, which has a wire mesh over the opening. There no dotted line above the opening MB3 valve :-\) http://www.uboatarchive.net/U-570/U-570Plate28.htm (http://www.uboatarchive.net/U-570/U-570Plate28.htm)

Q. Was there a gasket on the venting valves, or just metal on metal?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Feb , 2017, 19:28
Hi Simon,


I don't have anything to prove there is a wire mesh above the vent for the Type VII, but I believe there was.  Your, 2D drawings show the mesh.  I do have a quad-vent valve set for the Type IX that has the mesh.  I got that from Maciek...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Feb , 2017, 22:54
Hello Mr. Tore,


I change the Oil and filter on my car every 3,000 miles...  Do you remember how often they changed the 2 lube oil filters on the Type VII C diesel engines?


Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Feb , 2017, 23:51
Hello Mr. Tore,


Your opinion about the text and diagrams...


Regards,
Don_


"Lower Left - The return of the lube oil from the diesel engine can be switched to either of the lube oil system tanks (port or starboard). In the case of contamination (possibly seawater) you are able to isolate and clean the contaminated oil. This system is based on a lube oil centrifuge cleaning system which was removed on the later VIICs. However, you are  able to draw lube oil from either of the system tanks by using the fuel transfer pump as a spare lube oil pump as indicated on the image below.


Lower Right - The original centrifuge system had two pumps, one for dirty lube oil from the system tanks to the centrifuge and one for supply of clean oil from the centrifuge to the system tanks. On the later lubricating oil two (2) larger oil filters eliminated the need for the centrifuge purifier and the pumps. I don`t have a system sketch of the later system showing the exact location of the filters. However, the photo shows the two (2) filters in close proximity of the engine control panel. The hand pump mounted on the aft engine room bulkhead is used to dump contaminated oil overboard from either of the system tanks or the dirty oil tank.


Blown Head Gasket


Engine misfire with a gasket head-to-head leak causes lowered compression which results in a rough idling engine. Damage of this type may not cause overheating, coolant in the oil or any other outward sign. Overheating from a blown gasket when a head gasket fails between a combustion chamber and the cooling system, a loss of coolant and overheating are often the result. Oil in the coolant and coolant in the oil; head gaskets may also fail between the coolant passages and the lubrication system. This type failure may show up as oil in the coolant or coolant in the oil. Unfortunately, this failure will destroy the ability of the oil to lubricate and change the viscosity of the oil. The results could be a ceased up diesel engine."

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2017, 01:33
Tore, Don, & Maciek.

Q. Would there be a wire mesh over the opening for the MB3 valve? (I just noted there a dotted line above the opening of the MB & RTO Tank, which has a wire mesh over the opening. There no dotted line above the opening MB3 valve :-\) http://www.uboatarchive.net/U-570/U-570Plate28.htm (http://www.uboatarchive.net/U-570/U-570Plate28.htm)

Q. Was there a gasket on the venting valves, or just metal on metal?
Simon.
I believe the MBT3 vents had a protecting wiremesh on top. I  think the vent seatings were metal to metal.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2017, 02:57




Hello Mr. Tore,


I change the Oil and filter on my car every 3,000 miles...  Do you remember how often they changed the 2 lube oil filters on the Type VII C diesel engines?


Regards,
Don_ 
Don.
I don`t think you can compare a disposable car luboil filter with a complex large marine diesel luboil filter. Normally a marine luboil cleaninginstallation have sentrifuges. Such installation add weigth and require space which make it difficult to accommodate in a submarine. When the VIIC/41 was introduced weight become a problem as the increased diving depth required a heavier steel plating and every possible excessive weight had to be removed. The lubeoil sentrifuge and the reversing of the diesel engines were sacrificed and a large sofisticated lubeoilfilter was installed. Such a filter do not have a disposable insert as on the car engines, but are of a "selfcleaning" type, either by means of a reversible oilflow,back wash type, flushing the contaminations to the dirty oil tank or  a "knife filter" which has a long rotary steel knife ( brush) along steel steel filter insert which skims off the contamination dropping it to the bottom of the filter where it is drained to the dirty oil tank. I guess the VIIC had the first type for the lubeoil- and for the fuel the "knife" type filter after the fuelfilters. In your text showing the filters on the front of the engines it seems to me you are mixing up the double fuelfilters with the lubeoil filters. The VIIC lubeoil filters are single,  much larger, some 400 mm diameter and 600mm long,  and not generally visible, placed under the floorplating forward engineroom in the area where the  sentrifuges used to be.
As to the fuelfilters attached on the front , you have a port and starboard fuel knifefilter placed behind the hp fuelinjection pumps as shown on the image below. 
The drawback with lubeoilfilters is watercontamination, quite common on a submarine. You had to rely on a certain settling in the systemtank, however if the lubeoil emulsified you are lost, it happened once in three year with me.
Otherwise I believe the text is OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Feb , 2017, 03:47
Simon.
I am not sure of you text under blown head gasket and watercontamination. A leakage of water into the lubeoil system is not possible by a "blown gasket" between the cylinder liner and coolingwater system. As you`ll see from my image below, the upper part of the cylinderliner is raised uncooled in the way of the cyliderhead joint with the liner. Yet we had quite often the cylinders filled with seawater which in some rare cases caused emulsificaton of the lubeoil. The main reason for the waterintrusion was a leaking main hull exhaustvalve. These valves although equipped with a pneumatic grinding machine had a tendency to leak, some times filling the exhaust manifold and the cylinders with seawater submerged. As previously told, our starting routine was always to blow through the engine with the indicatorcocks open to blow out the water prior to starting, to prevent waterstroke. We even did that after diving to prevent water accumulating just after the dive, however as this increased the internal pressure in the boat we had to restrict such procedure. Yet seawater contaminations happened by leakages through the pistonrings down to the luboil systemtanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Feb , 2017, 15:20
Hello Mr. Tore,


The 'Blown Head Gasket" was my post...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Feb , 2017, 00:46
Vent valve for MB & RFO 2 Tank (Stb)

(https://c1.staticflickr.com/3/2520/32031603534_b7ce724b55_o.png)
Fig. 1. Vent valve for MB & RFO 2 Tank.

(https://c1.staticflickr.com/3/2433/32059950573_e0e1e24ef2_o.png)
Fig. 2. Vent valve for MB & RFO 2 Tank.

(https://c1.staticflickr.com/3/2083/32031607244_b12417c70b_o.png)
Fig. 3. Under deck view of the vent valve for MB & RFO 2 Tank.

(https://c1.staticflickr.com/1/503/32059952603_b0941cfa16_o.png)
Fig. 4. Deck view of the collection for the valve for MB & RFO 2 Tank.
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2017, 01:20
Simon.
I guess the gatevalves are ok, but may be you should make som strengthening ribs on the valve casing and a bit heavier stuffing Box, see my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2017, 02:14
Simon.
As far as I remember the gatevalves did not have valve spindle extensions to the casingdeck. Wooden  deckhatches would be more appropriate. Particularerly for the isolating gatevalves, as at sea the casingdeck was awashed  all the time, operating the valves was difficult.  Hence a conversion to the fuel storage mode was usually done alongside in harbour.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 13 Feb , 2017, 03:45
@Simon.


To answer your previous question. We currently have a command room in our build and it's triangle count is at 1.6 million. But it will quickly add up since in VR you need to render for both eyes. So 3.2 million for command room. Adding to some custom texture compression techniques that needs an extra geometry pass and the triangle count goes around 5 million. We are baking all our lighting but if we used realtime lights with realtime shadows then the triangle count for one room would easily reach over 10 million. But we are not going to use realtime lights. Also added minimal visual effects like bloom and slight color correction (https://www.dropbox.com/s/03y2dw06ry6hn8j/Screenshot%202016-12-30%2018.27.54.png?dl=0 (https://www.dropbox.com/s/03y2dw06ry6hn8j/Screenshot%202016-12-30%2018.27.54.png?dl=0)  <-- here is me trying to achieve Das Boot film LUT) and the pixel fill gets more expensive.


Then there are PBR materials, every material has a separate texture for albedo, specular, roughness, normal, ao, metallness and they all need to be as high as possible since you don't want visuals break down when inspecting object up close. Final touch is using 4xMSAA to get rid of all the pesky geometry alias and rendering this all becomes quite challenging. We need to keep it at 90 frames per second.  Luckily current generation GPU-s can chew trough triangle count pretty easily but trying to add this other stuff and the bottle neck will be quick to come.


That's the biggest challenge, how to balance this all that it would still look and run good.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Feb , 2017, 05:14
Karel.
I have of course no idea about creating a submarine game,but could`t resist to compare the Das boat scene, which I assume indicates das boot is under attack, with a journalists photo of me on KNM Kaura ex. U 995 demonstrating a submerged dummy attack. I guess the photo is pretty close to the area shown in the moviescene. Note the periscope on my photo is of the original type not the type fitted on present days U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Feb , 2017, 05:35
Simon.
As far as I remember the gatevalves did not have valve spindle extensions to the casingdeck. Wooden  deckhatches would be more appropriate. Particularerly for the isolating gatevalves, as at sea the casingdeck was awashed  all the time, operating the valves was difficult.  Hence a conversion to the fuel storage mode was usually done alongside in harbour.
Tore

Tore, you are correct.
 
While researching the deck of the late war Type VIIC’s. I did noted that the German's had replaced these two small metal hatches, with wooden hatches on the late war Type VIIC’s.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Feb , 2017, 12:04
Simon.
As far as I remember the gatevalves did not have valve spindle extensions to the casingdeck. Wooden  deckhatches would be more appropriate. Particularerly for the isolating gatevalves, as at sea the casingdeck was awashed  all the time, operating the valves was difficult.  Hence a conversion to the fuel storage mode was usually done alongside in harbour.
Tore

Tore, you are correct.
 
While researching the deck of the late war Type VIIC’s. I did noted that the German's had replaced these two small metal hatches, with wooden hatches on the late war Type VIIC’s.

Tore, I was thinking about this hatch last night.
 
I am starting to think that they used this metal hatch throughout the whole war. We must remember that this section of the deck on KNM Kaur was rebuild, and I found this metal hatch on U-826 that was launched March 1944. It thinks I can see this metal hatch also on very late war U-boat like U-1305 & 1306, but the photo are very poor and impossible to be 100% sure.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Feb , 2017, 23:04

Hello Mr. Tore and Maciek,


While reviewing the German Diving Regulation Manual I found the following in Section I, Page 5:


"When orders concerning the operation of shut off valves are given only the words "open" and "close" are to be used.  In feedback about the position of the valve only the words "on" and "off" are to be used.  Words such as "shut, tight and opened", are prohibited"


Is this a translation issue, or is this a German Navy Vs Other World Navies?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2017, 01:22
Don.
Orders, particulary on a submarine have to be clear and not to be misunderstood, the various navies have a standard vocabulary  to be used in their own language in order to prevent misunderstandings. It is a challenge to translate a submarine manual into a correct naval wording, as you got to have substantial naval submarine experience in both relevant navies to use the right wordings. In our navy we experienced this difficulty during WW2. Before the war our submarines were designed based on German technology and a substantial part of our submarine wordings derive from the german language. During the German occupation of our country, the Norwegian navy continued to fight the war out from UK, eventually getting British submarines and training. Our submarine language was thus very much "anglofied" and adapted to the Roayl Navys (RN) technology. After 5 years of exile our navy returned to Norway and eventually took over some VIICs, again the manuals were translated based on German naval language into Norwegian UK navy language.  A typical difficult translation is the order for the use of "Untertriebzelle" which is a bit different from the UK submarines "Q" ( quick diving tank).  A german submarine, operating in hostile waters very often have the "Untertriebzelle" filled and used  to overcome the "surface resistance" during a quick diving.
The "Untertriebzelle" was blown at some 10-14 meters to save air. At that depth the order "Aussgleichen" was given and the "Untertriebzelle"s kingston was shut and an inboard venting relieved the pressure in the "Untertriebzelle".  Such procedure was not used in the RN and thus no relevant RN english word exist for the "ausgleichen",  some English translator have made a word for "ausgleichen" calling the order "Express" which for me is a strange word for the procedure. We used " vent Q", meaning shutting the Kingston and open the vent, relieving the air through the silencer into the control room. Sorry for the long story, hopefully it might describe the problem of finding adequate naval words for translating. I guess the similar problems exist between the US and RN english, the worst would be to mix the two languages, to my opinion any manual or technical book on submarines should mention which naval language is used.
In a RN submarine training course it is emphasised, no use of the word close, only shut is to be used.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Feb , 2017, 13:08
Has anyone see a photo(s), or know the pipe diameter of the Exhaust Gas Blowing Manifold? http://www.uboatarchive.net/U-570/U-570Plate16.htm (http://www.uboatarchive.net/U-570/U-570Plate16.htm)
 
It was tight the first time I added the Manifold, but now after adding the Vent valve for MB & RFO 4 Tank (Stb), I would not say not tight no more, I almost look imposable ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Feb , 2017, 16:14
Tore, I imagine the drain valves for the piping of the MB & RFO tanks 2 and 4 will be at the lowest point? http://www.uboatarchive.net/U-570/U-570Plate16.htm (http://www.uboatarchive.net/U-570/U-570Plate16.htm) (valve 'm')

Plus, any idea that it may look like?

(https://c1.staticflickr.com/3/2010/32865234286_83797a5b59_o.png)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Feb , 2017, 00:01
Simon.
I guess placing the ventduct draining valves close to the gatevalves would be OK. I don`t have any images of same but I think the look would be pretty much like the drainvalves on the outboard exhaust cooling system (silencer) which I presume you have drawn previously.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Feb , 2017, 02:52
Hello Mr. Tore,


Are the dual fuel oil filters mounted on the maneuvering panel on the GW Diesel engine the last filters before the fuel oil injection pumps.  I would think so, but I guess I need to consult the expert...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Feb , 2017, 03:10

Don.
I am afraid not, after the dual fuelfilters you have a knifefilter placed between cyl 1 and 2  just behind the HP fuelpumps. From this filter you have a drain to the dirty fueloil container placed next to the crankcase cover 1. See image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Feb , 2017, 14:32

Hello Mr. Tore,


Do you know how often the duel fuel oil filters were replaced?  They seem to be a pre-filter for the knife canister fuel filter which can drain its contaminant...


The fuel oil cleaning stages are as follows:


1. the gravity tank (contaminant separation and drainage)
2. the dual filters (replaceable cartridges)
3. the knife canister filter (contaminant drainage)


and finally to the 6 fuel oil injection pumps.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2017, 01:57
Don.
I don`t think the fuelfilters were replaced like disposable paper inserts, only cleaned. The double filter allowed one filter to be in operation while the other filter was cleaned. I cannot remember the exact frequency of cleaning.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Feb , 2017, 02:36
Don.
May be more complete fuelcleaning stages would be as indicated on plate 9 where the filters in the supply lines to fuel bunkertank and the day- (setling)tanks are indicated.
The system plan 9 might be a bit confusing as they have not used a GW arrangement but the fuelpipe arrangement of a MAN engine having the engineattached fuel supplypump and filters placed aft. The final knifefilter in the supply pipe to the HP fuelpumps is not shown.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Feb , 2017, 02:27

Fuel filters.
In order not to create confusion it might be good to mention that the first filters in the fuelling pipe were not really filters but mainly strainers having a coarse mesh basket. We used to call it the nuts and bolts filter. Sometimes you could really be astonished as to what some fuelling stations could "supply" and the nuts and bolts filter really caught nuts and bolts.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Feb , 2017, 18:36
Hello Mr. Tore,


I believe the diesel engineer is facing the maneuvering panel and the stern of the U-Boat with either diesel engine; GW or MAN.



The last drawing has me slightly confused...  Plan 9 shows the cap and the fuel oil loading connection which is on the port side of the U-Boat.  Your Plan 9 photo inserts seem to indicate the loading strainer/filter is located on the forward starboard side of U-995 against the bulkhead, although close to the diesel engine room walk-way???


Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Mar , 2017, 02:45

Don.
I agree with you it seems confusing, as you have two fillingpipes on each side of the engineroom door. May be we should not focus on the placing of the pipe on pipescheme. Below I have tried to indicate the system. The port hullvalve and strainer is for luboil bunkering. High up on the port side of the engineroom door you may see the plate on the strainercasing (difficult to read)  but seems to be mot. oelfilter (motoroelfilter) English "motoroilfilter". If the filter was a fuel filter the sign would read Trieboel, german for fueloil. Allthough the sign is doubtful I cannot make the nameplate read Trieboel. As the spare electric driven luboilpump can be used as a fueltransferpump, the fuel pipescheme shows a connection to the luboilsystem, however when fuelling, the shore fueldelivery usually had sufficent pressure to force out the compensatingwater and this pump was normally seldom used as fuel transfer pump when fuelling. I guess the fuel intake and strainer is on the starboard side having a short crossoverpipe from the strainer under the floorplating, going under the engineroom doorstep to the fuledistribution chest under the writing desk on port side.
I have tried to put up the idea on the sketch below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Mar , 2017, 21:29
Hello Mr. Tore,


If water got into the lube oil system/collection tank 1 or 2 through the piston rings...  Was there a drain cock that would allow you to drain the contaminating water from those tanks?

on second thought, after looking at Simon's drawing of those tanks, I don't believe there are any drain cocks for those 2 tanks...  if water got into one of those tanks, then how did you get the water out???


Possibly a access cap at the top to get access to the tank contents, and then use a hand pump with a flexible hose to evacuate the water???

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Mar , 2017, 00:44

Don.
When the Germans removed the luboil sentrifuges of the VIICs they installed under the floorplating large filters with water drain , I guess something like my image below. In addition they kept the handpump system shown on my 2. image below. As you can see when the lubeoil settled in the system tanks, water would be collected in the bottom of the tanks and could be pumped out by the handpump on the aft port engineroom bulkhead and discharged either to the dirty oiltank or overboard. The main problem was that in some rare cases the lubeoil emulsified and the water integrated in the oil, making a homogenius mixture with the oil and impossible to separate. In such cases you had to change the oil completely. It happened to me once.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Mar , 2017, 12:34
Hello Mr. Tore,


Do you have this image without markings?  Also, I believe valve "C" is in the shadows below.  Do you have a photo without the dark shadow? Was the lube oil hand pump on the aft Stb side?


Question - When you had the lube oil to emulsify; did you have to shutdown the diesel engine on that side? Was the results damage to the bearing journals, and most other moving parts? Or was you able to dump the emulsified LO and pump uncontaminated LO in to recover the engine?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Mar , 2017, 14:41

Don.
I don`t have the same photo, but almost a simular taken by falo as shown below. The handpump is on port side aft engineroombulkhead.
 In answer of your emsulsify question. Yes we had to shut down the engine immediately and did not have any dammages. We limped back to the base on one engine. And pumped the contaminated oil ashore.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Mar , 2017, 21:34
Hello Mr. Tore,


Thank you for all your help...  One more question - was the lube oil purifying centrifuge pump located near the forward diesel room bulkhead on the starboard side of the early U-Boats?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2017, 01:59
Don.
I never saw the luboil centrifuge, but I assume it was placed somewhere up front of the engines.  It was possibly an unit where the pumps and valves were intergrated in a fairly small module.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Mar , 2017, 02:49

Hello Mr. Tore,

These two photos make me believe it was on the starboard side because if the white vertical tubes in back of the purifier...   What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2017, 04:51
Hi Gentlemen,

Don, I believe that purifier was located in the port-forward corner of Diesel engine room.
At the attached photo you can see the British sailor operating stb engine (of HMS Graph).
As you can see, he stands rather freely.
On the other photo:
(http://uboatarchive.net/U-570/U-570Photo25.jpg)

you can see the port engine. In the bottom-right corner of the photo you can see the rounded cover of some device
(which - I believe - is not present in the stb corner). It can be the top of the vertical cylinder, the part of purifier, also
visible on the photo of the device from U 505.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2017, 05:14
Don.
The white purfyer on your image seems to me to be an installation on a merchant vessel, definitely not on a VIIC, but could indicate how a centrifuge module would look like.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2017, 05:33
Tore,

The white purfyer on your image seems to me to be an installation on a merchant vessel, definitely not on a VIIC, but could indicate how a centrifuge module would look like.

The white purifier is installed in the U 505 engine room.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Mar , 2017, 05:53
Maciek.
I guess you found it. The device encircled in red would probably be the luboil purifier. On the museum U 995 this equipment is not fitted. Instead you have a horizontal electric waterpump which I guess supply hot seawater to the galley and other sanitary seawater systems.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Mar , 2017, 14:38
Hello Mr. Tore and Maciek,


I don't believe I came up with the photo of the White Purifier that I posted.  However, after doing some searching through my photos scattered between two hard drives (I need to organize this mess!!!), I found a photo of U-505 which seems to indicate the White Purifier belongs to U-505.  I have posted the photo below...  What do you all think about my theory?


Is the gray item close to the bulkhead a electric pump, or the electric water heater that was part of the LO Purifying system.  If that is not the electric water, then where is it on this image of U-505?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 03 Mar , 2017, 14:44
Don,


the purifier for sure belongs to U 505. Here is the link to virtual tour, where you can see it (you have to have QuickTime plugin installed):
http://archive.msichicago.org/exhibit/U505/virtualtour/vr_tour/movie_diesel.html


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Mar , 2017, 22:21
Hello Mr. Tore and Maciek,


I just had to understand how the lube oil purifier worked and why we needed the hot water heater.  I understand the reason for the preheating of the lube oil is to assist in separating the water already in the lube oil besides the contaminants. The reason for the electric water heater is for cleaning the centrifuge bowel of sludge that has collected on the sides of the internal bowel.  I found a video that does an excellent job of explaining how the process works with a modern centrifuge. 


https://www.youtube.com/watch?v=00eVuhB7aTQ


However, the centrifuge in the U-Boats was designed in the 1930's and they didn't have the computerized control unit ti initiate the various cycles, but I bet there was some type of control switch or valve where this was done manually.


Comments?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2017, 00:41
Don.
The 1930 marine technology was not so automated as todays. The separators as we called it, had to be cleaned manually and I assume the VIIC separators was cleaned manually as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2017, 01:37
Hello Mr. Tore,


The separator was designed by "Ramesohl and Schmidt, Westfalia., Oelde


GEA Westfalia Separator Group GmbH with head office in Oelde, Westphalia is a German manufacturer of separators and decanters which is affiliated to the GEA Group. The company develops procedures and processes for the mechanical clarification and separation of liquids for the food industry, chemicals, pharmaceuticals, biotechnology, energy, shipping and environmental technology.



1931–1940


In 1931 the company presented the first self-cleaning separator. Co-founder Franz Schmidt died on 18. March 1937. In 1940 the turnover surpassed the 10 million Reichsmark limit for the first time.


Patent DE470723C Filing date Jun 7, 1925 - Publication date Jan 25, 1929

Standing fluid centrifugal drum with upper supply and removal of the material to be centrifuged by axial pipes

I found this on the internet,
 
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2017, 03:12
Hello Mr. Tore,


I updated pages 140 - 143 in Skizzenbuch and posted the latest version in dropbox.  When you have time would you please review those pages and let me know what you think...  This version of Skizzenbuch has had a lot of updates and superficial changes; like moving pages to make things more logical in sequence.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 04 Mar , 2017, 06:56
Don,


according to British report on HMS Graph:

Lubricating Oil Separator, Type 2 LHD 2/20
Capacity:   300 litres lub. oil/hour at 1 atm. at a speed of 1350/1,750 r.p.m. (66 galls./hr. at 15 lb./sq. in.).
Makers: Ramesohl and Schmidt, Westfalia, Oelde.
Motor Makers: Werdohler Pumpenfabrik, Werdohl, I/W Paul Hillebrand G.M.B.H.

In the type VIIC manual there is a chapter that describes the purifier:
An electrically driven purifier with a capacity of 250 liters/hour is provided in the diesel engine room for purifying dirty lubricating oil.  The purifier is equipped with an electrical oil pre-heater and a hot water pre-heater.  Directly coupled with the drive shaft are the pure oil and dirty oil feed pumps.  These two geared pumps arranged one after the other.  The attached dirty oil pump sucks the contaminated oil from the lubricating oil collecting tanks and passes it over the oil pre-heater into the lubricating oil purifier.  The cleaned oil is then pumped by the pure oil pump.
The waste water from the oil purifying process drains into the bilge.  A hot water pre-heater is provided for better cleaning of engine lubricating oil.

The correct manufacture name is: Ramesohl & Schmidt A.G., Ölde i. Westfalen.


Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Mar , 2017, 07:18

Don.
I just had a brief look at your latest Skizzenbuch new text starting from page 141. On page 142 you are showing the lube oil cooling system naming the coolers luboilcannister filters. On this drawing the filters are not shown. I guess I made a mistake when I commented on your mixing up the double  fuelfilters with the luboilfilter posting the wrong image of Simons luboil system. Down below is a right image from Simon and the traditional lubeoil scheme where I have tried to indicate the positions of the lubeoil filters. I guess you should reduce the dimension somewhat down to say 200 mm  diameter. The filters are usually placed before the coolers as you have less resistance when the oil is warm. To show all the systems on top of each other makes it difficult  to read and understand and might be confusing. Reverting hopefully tomorrow.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2017, 22:23
Hello Mr. Tore,


There are two electric piston pumps located on the right top and bottom of Simon's drawing (look like round circles). I believe these are the diesel engine water cooling pumps.  If one water cooling pump fails, then can 1 water cooling pump cool both diesel engines?  It looks like they could function in that way...


The basket type filter on the initial lube oil loading line serves to catch the nuts and bolts.  So, did they replace the 2 basket type filters with 2 knife type filters that were placed very close to the valve chest?

Does the labeling look correct on the attached photo?  What is the large red cap for at the bottom of the photo?

Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 00:43

Don.
In order not to get confused I take one question at the time. The "round circles" on Simons image are not electric driven pistonpumps, but the well known port screw "Imo" spareluboil/ fueltransfer pump and the other the spare electric driven seawater centrifugal pumps as indicated on my image below. Please note that the original seacoolingwater scheme has a mistake as the suction for the electric driven seawaterpump has a suction connecion to the main crossover seawaterpipe . The pump can indeed be used as spare coolingwaterpump for both engines.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 00:56

Don.
The attached piston coolingwater pumps are located well below the floorplates and are not easy to see. Below is an image of the double pistonpump driven off a gearwhweel on the crankshaft just aft of the vibrationdamper on the front of the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 01:06
Don.
 Basket strainers. If you mean the lubeoil filter before the lubeoilcoolers I don`t think they are replacement. In the old systemplan you`ll see there is a differential manometer to survey the pressuredrop over the filter, so I guess it could be classified as the main lubeoilfilter.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Mar , 2017, 01:48
Hello Mr. Tore,


These filters and pumps are really getting to me.


1. I now understand the water cooling pumps (location) are an integral part of the diesel engine.
2. I now understand the lube oil pumps (location) are also a integral part of the diesel engine.
3. Is there a way to disable the lube oil pump mechanically so it's not running when you want to change it out?
4. Did you change out a lube oil pump while the diesel engine was running?
5. If so, is the lube oil pump configured in a by-passed, or isolated mode, so it may be changed and not get pressurized lube oil feed from the aux. Lube oil pump if it's supplying lube oil to the running engine?
6. What are those 2 electric lumps for in the opposite corners of the forward bulkhead used for?
7. If a water cooling pump fails can it be replaced on a war patrol?
8. Is there any possible valve chest switching to allow one pump to supply cooling water to both diesel engines?


I should know or be able to figure this out this stuff on my own, but I just don't want to get this wrong...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 02:11
Don.
Labeling photo. I am afraid you have to correct the labeling. Below you`ll find my corrections, but you really have to go into the lubeoilsystem to have a correct understanding.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 02:23

Don, your last questions. Again you have to study the whole lubeoilsystem to have a complete understanding as there are many options to operate the system. You can indeed run the main engine disabeling the attached coolingwaterpumps, I have done that myshelf when the port engine coolingwaterpump broke down. If the drive of the pumps are mechanically OK, you can operate the valves so you are able to connect one of the systems to the other f.i. operate the port engines attached pump to serve the stb as well or to operate the system by the electric centrifugal seawaterpump. Normally you dont`carry a complete pump with drive and casing as spare due to spaceproblems, we had to get a new from base as the piston conrod got loose, smasing the casing. You cannot be sure to be able to continue a war patrol on two engines if you have a brake down, it all depends on the collateral damage, that is the drawbackof attached auxilliaries.

Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 02:47

Don.
I am not sure if I understand your question 6. about two electric lumps?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Mar , 2017, 05:29

Hi Don,

6. What are those 2 electric lumps for in the opposite corners of the forward bulkhead used for?


If you mean electric pumps in the forward port and forward stb corner of the Diesel engine room, the one in the port corner is auxiliary/emergency lubricating oil pump (and transfer fuel oil pump). This pump was used to force lubricating oil through all friction surfaces of the engine, before it is started up (and when the individual lubricating oil pump driven from the crank shaft is not running). Of course, it was also used when the crank shaft driven pump is out of order.
When used as fuel oil transfer pump, this pump transfers fuel from external fuel oil tanks (tankers, depot ships and so on) to the boat's fuel oil tanks.


In the stb corner is the auxiliary cooling water pump, used when the individual cooling pumps driven from crank shafts are out of order and to cool down the diesel engines after they were stopped (and when individual cooling pumps also were not working).


These pumps are vertical shaft, centrifugal pumps. The parts visible above deck plating are the electric motors, the pumps themselves are below deck. Such arrangement (similar to all other pumps) is to protect motors from splashes and water (even if pumps are flooded due to high water level in bilges, the motors are safe).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Mar , 2017, 09:00
Done.
I guess I did not answer your question on the atteched luboilpump which is a gearpump. It goes the same way as for the attached piston coolingwater pump. you can remove the pump in case of damage and isolate the pipesystem connected to the pump. In such case you use the electric driven screw lubeoilpump on the port side and direct the oilflow as indicated on my image below shortcutting the attached gearpump.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Mar , 2017, 16:29

I would like to make some comments to my previous post:

6. What are those 2 electric lumps for in the opposite corners of the forward bulkhead used for?


If you mean electric pumps in the forward port and forward stb corner of the Diesel engine room, the one in the port corner is auxiliary/emergency lubricating oil pump (and transfer fuel oil pump). This pump was used to force lubricating oil through all friction surfaces of the engine, before it is started up (and when the individual lubricating oil pump driven from the crank shaft is not running). Of course, it was also used when the crank shaft driven pump is out of order.
When used as fuel oil transfer pump, this pump transfers fuel from external fuel oil tanks (tankers, depot ships and so on) to the boat's fuel oil tanks.


One more use: taking the lubricating oil into the boat's tanks.

These pumps are vertical shaft, centrifugal pumps. The parts visible above deck plating are the electric motors, the pumps themselves are below deck. Such arrangement (similar to all other pumps) is to protect motors from splashes and water (even if pumps are flooded due to high water level in bilges, the motors are safe).


The auxiliary lubrication pump is not centrifugal type (as I have written before) but worm type pump, with one main rotor (driven by electric motor) and one auxiliary rotor (rotated in the opposite direction), both in vertical arrangement. The oil is pumped up from the bottom.



The auxiliary cooling pump is centrifugal type pump, not self-suction, i.e. it has to be flooded to work (but it is not a problem, because the water level is always above the pump).


--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 05 Mar , 2017, 16:33
Regarding the previous post about filters, I have attached some images of the filters (not necessarily used on U-Boats, but from that period).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Mar , 2017, 18:38
Hello Mr. Tore,

Page 123 - The Büchi turbo charger was never used at lower loads; the tuning of the exhaust/inlet cams was adapted to higher exhaust pressure even on U-Boats without a schnorchel.

1. Should that be the roots supercharger was never used at lower loads?
2. I thought the Büchi turbo charger was always engaged on the MAN diesel engines
3. Did the Germans tune the exhaust/inlet cams to adapt to higher exhaust pressure for schnorchelling?
4. I believe a MAN diesel engine would have the Büchi turbo charger engaged while schnorchelling, but I'm not sure that a GW Diesel engine would have the Roots supercharger engaged while schnorchelling because of the 6 knots speed restriction (stress/snap the schnorchel mast).

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2017, 01:10
Don.
I guess it is a misunderstanding stating the Buchi turbocharging system was never used at lower loads. This relates to the Roots blower. The Roots blower required a lot of energy to operate and did not contributed to a higher efficiency of the GW diesel to compensate for the higher power requirement,  hence you only increased the fuelconsumption, so you disengaged the blower at lower loads. The Roots blower was merely a device to boost the max. power of the engine when higher output was required. The MAN turbocharger utilised the energy in the exhaustgases thus using the waste heat energy to operate and hence contributed to a general higher efficiency e.g. lower fuelconsumption and could not be disengaged.
On the non reversible GW engines you had only one set of valvecams. I don`t know for sure but assume on the MAN turbocharged engine you possibly had two sets of cams using adopted cams on the reversing shaft, this might be due to the exhaust gas turbine.
When schnorcheling you primarily was charging the batteries, using low speed propulsion on E motors  as we had speed restrictions.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 06 Mar , 2017, 06:47
Hi Tore.


Can you tell me  how did the crew know when the boat was in balance? I am looking trough panorama pictures and cannot seem to find any indicators that would show this kind of information.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2017, 08:31

Karel.
Getting the submarine in balance can be many things, in fact a VIIC submarine was very seldom in 100% ballance as temperature, watersalininty and the daily life of 46 men altered the parameters all the time. The first step would be to calculate the estimated deadweight and adjust the regulating tanks accordingly prior to the test diving. At the first testdiving you checked how close your calculation was and made adjustment by the regulating tanks checking the Papenberg depth gauge. The alongship trim was checked by the inclinometer and adjusted by the forward and aft trimtanks, and a possible atwartship list was checked by a simple inclinometer weigth hanging on the atwart bulkhead and adjust the port and starboard regulatingtanks. Down below I have made an image of the systems. Next to the Papenberg column we had an image of the periscope so you could see the position of same relative to the seawatersurface. On some submarines you even had an image of the schnorchelmast top relative to the seasurface. You very seldom was "hanging" motionless in perfect ballance, mostly the balance ( within limits) was kept dynamically by speed and hydroplanes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Mar , 2017, 08:32
Hi Karel,

check this thread (http://uboat.net/forums/read.php?3,92539,92539#msg-92539).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Mar , 2017, 11:19
Hello Mr. Tore and All,


Does anybody have good photos of the Aux Water Cooling Pump/Transfer Pump in the diesel room, and the Water Cooling Pump for the e-motor bearings and thrust bearing cooling? Mine are not too good...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 06 Mar , 2017, 11:46

Hi Don,

Does anybody have good photos of the Aux Water Cooling Pump/Transfer Pump in the diesel room, and the Water Cooling Pump for the e-motor bearings and thrust bearing cooling? Mine are not too good...


Check your mailbox. The electrically driven cooling water pump in the aft torpedo room (behind the main switchboard port) was also used (primary) to cooling E-motors (or to be more strict, cooling the air used to cooling the motors) and cooling (and lubricating) the shaft strut bearings.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2017, 15:23

Don.
I guess you mean the aux. coolingwater pump on stb side, forward end of the main engine. Which is a vertical centrifugal pump of Odesse, Oscherleben type G 80/180 capacity 800 l/min against 3 kg/cm2. Unfortunately I have no photo of same. Might be you are able to find an image on the net.
The centrifugal coolingwaterpump in the e-room is of a different type than the stb aux. coolingwaterpump in the engine room  as it operate against a higher head, 12 kg/cm2. The reason is cooling of the propeller shaft seals,main thrustbearings , aircoolers and bearings of the E-motors/generators. Make Klein, Schanzlin & Becker. The pump is on the image below.
The aux. luboil/ fuel transferpump is of a vertical screw pump make Leistritz, Nuremberg. Capacity 38m3 against 50m WC. Suction 5m WC.
The lubeoil system plate 14 has a wrong icon for the aux lubeoil/ fueltransferpump marked as a centrifugal pump, below I have made a correction.The reason for using a screwpump for the lubeoil/ fuel is a centrifugal pump create cavitation and gas bubbles in the oil. Most probably the screw pump would be a triple screwpump having one center drive spindle and two outer idle.. The manufacturer is still in existence and on their webside you`ll find images of their screwpumps, they still make pumps for submarines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Mar , 2017, 20:51
Hello Mr. Tore and Maciek,


Do you all have a better photo of the auxiliary water cooling pump then what I have? Perhaps a little wider?
... And it is a centrifugal type pump correct? Also, what is that drive shaft above the pump?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Mar , 2017, 23:51

Don.
The aux. coolingwater pump is, as I stated, a vertical centrifugal pump of make Odesse, Oscherleben, type G 80/180 with a capaciy of 800 l/min against a head of 3 kg/cm2.
The driveshaft  shown on the top of your image is the mechanical driveshaft for the hand operation of the aft hydroplanes.
Kindly note the original coolingwater plan 13 has a mistake omitting the suction connection to the crossover pipe both for the stb engine attached piston coolingwater pump and the suction for the aux.centrifugal pump. I have corrected the plan 13 below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 00:09
OK, I will make sure it is fixed on my Plan 13...  Do you have a wider photo of the aux water cooling pump that shows some of the engine and the bulkhead?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 00:36
Hello Mr. Tore,


I have a general question about the lube oil with sea water contamination... From what I understand the intrusion path for the sea water is through a leaking exhaust valve during a dive (lets stipulate one side). If the lube oil collection tank has sea water at the bottom, then that means the sea water passed through the piston rings, the engine crank case. and finally ended up in the lube oil collection tank.


1. After blowing out the sea water from the cylinders, do you make any other checks before starting the diesel engine?
2. I believe before starting the diesel engine you would use the aux. lube oil pump to press oil through the diesel engine.  Perhaps the pressed lube oil will force any sea water from the crank case (I don't believe there would be any oil emulsification with that procedure)?
3. So, at this point the sea water would be pumped into that diesel engine's collection tank.
4. How did you know if there was sea water in that engine's collection tank, was there a procedure to check things out once it was determined that water was in the cylinders? or even still remaining in the diesel engine's crank case?
5. Could there ever be an issue with sea water below a good set of the piston rings that passed a compression test?


What I'm attempting to understand is how the diesel engine mechanic recovers form this situation...
6. He could start up the good diesel engine, but the problem side needs his love and attention.
7. How would you resolve the problem on the contaminated side?


Kind regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Mar , 2017, 01:51

Don.
Before the automation of the engineroom the engineers used hands, eyes, ears and noses to detect irregularities of the engines. Water in the lubeoil  as well as fuel might enter the system in many ways. The most common was the leaking of the main hull exhaustvalves. Leaking pipes in coolers/heaters and some times in watercooled exhaustvalves in the cylinder cover. Each leakage gave different indications. It would be impossible to list up all the different aspects, that`s why you got to have experienced engineers. F.inst. waterleakage in the exhaustvalve casing would be seen on the colour and temperature of the exhaustgas, water in the lubeoil could be detected by condensation droplets in the crankcase. When the oil settled in the systemtanks the hand pump could be used to have a visual check by looking on the discharge in the funnel.
You always would run the engines on air ( no fuel injection) prior to starting. Emulsification happens over some time, we checked the oil visually and when we saw sign of emulsification, the oil turned gray, became like mayonaise, we had to drain it from the system. This did not happen all the time, I experience this once in three years.
Piston rings can have a water leakage even if a compression test is OK. As piston rings have a split (gap) water can pass when the engine is not in operation. The main tigthening of the pistonrings do not come from the initial spring effect but from combustionpressure and compressionpressure leaking into the pistonring groves at the back side of the compressionrings, forcing the pistonring towards the cylinder wall.
Whenever the engine would be turned by air or manually you would start the  aux.lubeoilpump to protect the bearings.
The diesel engineers have many means to detect watercontamiation of the lubeoil, experience is the key and not everything can be put down on paper.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 12:28
Hello Mr. Tore,


Thank you for the detailed info on my questions about sea water in the lube oil...  It looks like the bottom line is when this happens and there is some emulsification, then it's time to end the war patron and head back to your home port for some needed repairs!


From what I understand, if there is a failure of the attached gear driven lube oil, or fuel oil pumps, then the aux pump may be activated if the situation requires both diesel engines running. Since these are driven by the diesel engine with metal gears pumping the oil, then what generally would be the failure mechanism? Once the diesel engine is shut down, then the mechanic may replace either pump, is that correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Mar , 2017, 14:45
Don.
Failure of attached pumps might be any thing. Normally a gearpump is very reliable, however on the direct reversible engines  the attached pumps did reverse as well and you got to have intricate valve systems to make the pumps work running astern. These complications are only related to the gearpumps like the fuel and lubeoil pumps and not the reciprocating pumps like the piston coolingwaterpumps. so you might experience trouble with the valvesystem. On the front of the engines you`ll see the pipesystems for both the fuel and luboil where you can operate the systems alternatively shortcutting filtes and pumps by shutting cocks and valves.
Usually you could repare or exchange the pump easy, the nightmare would be to have a major damage to drive from the crankshaft. However every system has many alternative operations and you would almost always find an emergency solution thanks to the flexibility of the systems.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 16:18
Hello Mr. Tore,


You would only change-out a failed attached gear pump when the diesel engine is shut down, is that correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 17:19


Hello again Mr. Tore,


I have come to realize that this engine lubricating system is so complex with many variables... I was studying the hand pump for manually pressing lube oil through a selected diesel engine. I don't know why they would use a hand pump when they have that huge aux. lube oil pump sitting on the port side?


1. I have colored in the pipes for when the hand pump is being used to press USED lube oil to a diesel engine (BLUE - is suction, and RED - is pressure). Valve "a" is open to allow the hand pumping to draw oil from the selected collection tank, and valve "c2" must be shut because we don't to draw CLEAN oil from the storage bunkers. Then through the hand pump, and valve "n" is shut because we don't want the oil going to the tank for filling oil cans, and finally valve "b" is open to press the lube oil to the diesel engines.


- It looks like that works OK (YES or NO)?


2. I have also colored in the pipes for when they want to pump CLEAN lube oil to the tank for filling oil cans (GREEN - is suction, and YELLOW is Pressure). In this instance I think valve "c2" must have 3 positions (left - off - Right). The left or right positions permit the selection of a CLEAN oil storage tanks, and the "off" position relates to the above procedure when pressing oil to the diesel engine. Then through the hand pump, and valve "b" must be shut to direct the CLEAN oil into the tank for the oil cans.


- It looks like that works OK (YES or NO)?


The only thing I question is Valve "c2" because it looks like an "L" type valve, but I believe it has to have an 'OFF" position. Also, it looks like there is a possibility to draw USED oil to the tank for the oil cans by having valve "c2" shut and valve "a" open?


- Did they ever want USED oil for the oil cans?


Drawing attached...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Mar , 2017, 21:26
Hello Mr. Tore and Maciek,


I believe I resolved the problem of a photo of the water cooling pump on the starboard side.  It's really impossible to get a good wide angle shot of a pump that's a bit down below the diesel engine room floor and large horizontal pump blocking the view.  So, I improvised...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2017, 00:06
Hello Mr. Tore,


You would only change-out a failed attached gear pump when the diesel engine is shut down, is that correct?


Regards,
Don_
Don, yes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Mar , 2017, 01:36
Don.
The large aux. lubeoil pump would require electricity which in spite of batteries was not always available, hence a small handpump to handle small quantities during maintenance work.
Q 1. It works for drawing ( green) fresh luboil in small quantities from port lubeoil storagetank the way cock2 is positioned. Would probably be used for filling the small daytank.
Q 2. It works. But remember the pipes are small, low capacities. it would probably be used for maintenance work on the engines like turning the engine manually.
Cock "n" to the lubeoil daytank could be shut. Generally fresh oil was used for the oilcans but if you would need larger quantities for maintenance work you would use used oil, but not contaminating the daytank with such oil. Indeed you could draw lubeoil in small quantities from the sumptank of each engine, remember the engines are of the dry sump type, but if you would take a sample of the luboil in the system of a relevant engine, you could use the handpump.
As I have stated before there are numerous ways to operate the systems describing one on the cost of others might be confusing and should be mentioned as an example of many.
Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 08 Mar , 2017, 01:41
Tore and Maciek. Thank you for answering my question.

I have another one about rudder gauge. I attached the screenshot and you can see there are red lines marked at number 25.  https://www.dropbox.com/s/hijz49wot1x8y4a/rudder.jpg?dl=0 (https://www.dropbox.com/s/hijz49wot1x8y4a/rudder.jpg?dl=0)
Can you tell me what this means? If i had to guess then rudder max turn angle was 25 degrees?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Mar , 2017, 01:44
Hi Karel,

I have another one about rudder gauge. I attached the screenshot and you can see there are red lines marked at number 25.  https://www.dropbox.com/s/hijz49wot1x8y4a/rudder.jpg?dl=0 (https://www.dropbox.com/s/hijz49wot1x8y4a/rudder.jpg?dl=0)
Can you tell me what this means? If i had to guess then rudder max turn angle was 25 degrees?

 The rudder maximum deflection is 25° when electrically driven and 35° when manually driven.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 08 Mar , 2017, 03:00
Hi Maciek. Thank you. This makes sense.
 
Can you tell me where the manual rudder was located?  In the aft torpedo room?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Mar , 2017, 03:04
Hello Mr. Tore,


Last question on the engines and oil, How do you turn those huge engines over manually?

I think I going to bed...  It's 5:05 AM!  I'm like a vampire, I sleep all day and work all might!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 08 Mar , 2017, 03:12
Can you tell me where the manual rudder was located?  In the aft torpedo room?

You are right, the main rudder manual control station is located in the aft torpedo room. There is an hand-wheel provided, which is coupled with the rudder drive shaft. When not used, the control column and hand-wheel is moved to the stowed to the port side (between the electrically driven air-compressor and main switchboard port), as currently on U 995 display (white slanted column and red hand-wheel):
(http://l7.alamy.com/zooms/4e4c0c6642f14a5982556e31d43d89ea/aft-torpedo-room-of-museum-submarine-in-laboe-ammrfw.jpg)

See also this photo from U 570 aft torpedo room.
http://uboatarchive.net/U-570/U-570Photo32.htm
Here, the hand-wheel is detached from the column.


If there was a need to use manual control, the column was moved to the center-ilne, as on this photo from U 505 aft torpedo room:
(http://rs288.pbsrc.com/albums/ll171/satanaka4711/356_zps3d3b8d19.jpg~c200)

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 08 Mar , 2017, 04:12
Much appreciated Maciek :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Mar , 2017, 02:59
Hello Mr. Tore,


I was reviewing Skizzenbuch and I came across the info on the day tank and the fuel oil system.  We noted that valve "e" had an unusual position that allowed fuel oil to go directly to the attached fuel pump on the diesel engine.


Could it be possible... If the attached fuel pump failed, then the auxiliary lube oil pump could draw fuel oil from a selected fuel oil storage tank. Then fuel oil is directed by valve "e" to the by passed attached fuel oil pump and on to the fuel injectors to fire the cylinders and keep the engine running.


Of course, the attached fuel pump would need to be changed when the engine is shut down.


Does this sound logical?


Image attached.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Mar , 2017, 05:27
Don.
I guess you should consider the fueltransfersystem independently from the daytank/headertank system. You filled the daytank normally by the compensatingwaterpressure using the head of the compensatingwater tank in the wintergarten casing, thus no use of the electric driven aux.luboil/fuel transferpump. As soon as the day-headertanks were filled the tanks were shut off from the compensatingwatersystem, hence no compensating pressure in the system. Usually one tank was selected  for supply, the other for setling. The daytank in the engine supplymode would generally initiate sufficient natural supplyhead to the attached gearpump. If the attached gearpump failed, the head of the daytank would probably not be sufficent for to overcome the pressuredrop over two filters in series and you would use the compensating system pressure as an emergency substitute for the attached fuelsupplypump. In that case you are shortcutting the day/setlingtanks and have a direct supply connection from the fuelstorage tanks to the dieselengine fuelsystem at the cost of no setlingtank.. Of course you might use the emergency fueltransfer pump as well but as you have to add compensatingwater anyhow I guess that would be superfluous.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Mar , 2017, 13:04
Hello Mr. Tore,


I obviously forgot to consider the header tank into the equation in the instance of a fuel pump failure.  That's why I have you as the expert! I didn't realize they turned off the header tank pressure to the internal fuel oil storage tanks on the surface (I only thought they did that when they dived the U-Boat); that would make sense because that would be one less valve to worry about when a dive situation is called for! However, the header pressure to the external tanks in the compensating mode to FBT 2 and FBT 4 can not turned off. (I don't think?).

I need to STOP guessing!



Mr. Tore, I have searched the internet for many hours today and I cannot discover what the head pressure from the fuel oil pump is to the injectors.  If you know the answer to that question, then you can set me straight. It looks like the header pressure can vary depending upon the height of the water in the internal fuel oil storage tanks. So this may affect the head pressure to the injectors as well???  Internal tank 1 has the height level much higher because of the side walls, but Internal tank 2's height is limited to the control room's deck.  Would Internal tank 2 be the only tank to select to by pas the fuel pump if it provided adequate head pressure to the injectors?


Regards,
Don_


PS - I did fine this gem of info...

A standing order states that when using Schnorchel U-boats may only use fuel from the external tanks.  Fuel is pumped from the internal tanks by using diesel cooling water, the pressure varying with the depth of the boat; if the boat is at 14 meters (46 ft.) the pressure is 1.4 atmospheres.  If fuel is pumped from the internal tanks with cooling water at this pressure the tanks are subjected to a pressure greater than that for which they are designed.
 
By approximate and experienced handling, however, ("cracking" the appropriate valve) fuel can be pumped from the internal tanks, but accidents are likely to occur and this may have been the reason for the order.

 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2017, 01:49

Don.
In order not to create confusion I guess you should have a correct understanding of the system. The fueltanks (bunker)are for storage and are seawater compensated from the diesel engine coolingwatersystem. The compensating pressure when the submarine on the surface is obtained by the head of the compensating tank in the wintergarten casing and do not relate to the coolingwaterpressure. When the submarine is submerged, the higher differential pressure in the external fuel storage tanks is still only obtained by the headtank. However if you open the compensating water board valves to the internal tanks you introduce the external ambient sea pressure to the internal tanks which might exceed the designed pressure for the internal fuelstorage tanks. For safety reasons the internal tanks have reliefvalves to prevent damages in such events. You might however, if you are experienced, be able at schnorchelling to crack the compensating water hullvalves so you throttle the pressure within safe limits in the internal fueltanks.
The fuel in the bunkertanks is generally transfered by using the compensating waterpressure, say to the day/setlingtanks in the engineroom. The latter tanks are not watercompensated and thus have a venting into the internal pressure of the submarine. Hence the supply to the gearpump on the main engine is done by the head of the day tank. The attached gearpump purpose is only to supply fuel by a common fuelpipe to the independent HP fuel injection pumps for each cylinder. As you have the double fuel filters on the front of the engine and the knife filter before the supplypipe to the HP pumps, the attached gearpump has to force the fuel through these filters.
Below is an image of the venting pipes of the fuel day/head tanks in the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Mar , 2017, 03:11
Hello Mr. Tore,


What you stated makes sense and I believe that I grasp your explanation...  The only question I have is does the internal storage tanks (especially Tank 2) have enough head pressure to permit fuel to skip the gravity tank and flow through the valve "e" central passage and supply fuel oil to the engine with a by passed failed pump? The failed pump can no longer draw fuel from the gravity tank, so this flow path does not exists anymore for that pump...


Kind regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Mar , 2017, 06:31

Normally the attached gearpump has sufficient pressure (some 2 m. wc.)from the daytank head at the suction side to supply the required amount fuel. Storage tank 2 has compensating waterpressure just as the other storagetanks, controlled by the head of the compensating tank in the wintergarten casing as long as the hullvalve for the compensatingwater is open. Surfaced the head in the storage tanks (some 5 m. wc.) would be sufficient to fill the daytanks.
 If the attached gearpump has a failure and had to be short cutted, the head of the daytank is probably not sufficient to force fuel through the filters in the supply pipe to the HP fuelpumps, hence you use the full compensating pressure ( some additional 2.m wc. to the daytankhead) to force the fuel through the fuelfilters and you to use the compensating water head directly to the fuelsupply pipe shortcutting the daytank, a indicated on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Mar , 2017, 13:36
Hello Mr. Tore,


That's what I was looking for, thank you...  After getting a good 7 hours sleep, my head is much clearer now!


I realize that the water column head pressure from the internal fuel tanks is about the same, and the water column head pressure would be less from FBT 2, R 1, and FBT 4 when in the fuel oil configuration.


I was thinking about fuel tank usage and this is how I perceive it would go:
1. R 1 for better/easier full ballast control when diving or at periscope depth
2. FBT 2 and FBT 4 converted to full ballast control, for better fuel economy (less resistance from a deep hull)
3. The Internal tanks in an alternating method as not to disturb the U-Boat's horizontal balance


What do you think?


Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Mar , 2017, 00:31
Don.
Within limits I agree. However the way the Germans used the VIICs I don`t think they had so many options. Before leaving for a warpatrol they had to store up as much fuel as possible. As previously stated we very seldom used the MBTs for fuel as our strategy was mostly coastal defense, having access to fuelling stations all along the coast.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Mar , 2017, 02:24
Hello Mr. Tore,


I know that the clutch may be disengaged between the e-motor and the propeller drive shaft when charging the batteries.  And I remember that the drive shaft break is applied when charging the batteries with that e-motor.  The only thing I have forgotten is why was the break applied?


Regards
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2017, 03:18
Don.
I don`t believe you had to disengage the tail clutch when charging the batteries as we used to top up the batteries while using the diesel for propulsion. Of course the engineers kept an eye on the load of the engines and adjusting the battery charging within proper limits.
When you are running on one engine the drag cause the other propeller to rotate. In the event that you did`t want the motor/ generator  to rotate you had to apply the break.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Mar , 2017, 03:23
Hi Gentlemen,

Patent DE470723C Filing date Jun 7, 1925 - Publication date Jan 25, 1929

Standing fluid centrifugal drum with upper supply and removal of the material to be centrifuged by axial pipes

I have found the this patent document (in attachment).

I have also attached two others patents that may bring some light to the solutions developed by Ramesohl & Schmidt A.G., Ölde i. Westfalen.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Mar , 2017, 03:55
Hello Mr. Tore,


I believe a full current charge at 1660 amps they just had the diesel connected to the e-motor as a motor-generator, and the prop was disconnected.


However, I believe your answer is correct about stopping prop spin on a side that is not running... (Thanks!)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 Mar , 2017, 05:09
Regarding various scenarios when different elements of the fuel oil/lubricating oil/cooling water systems are out of order (based on German manuals):
Lubricating oil:
normal operation: attached lubricating oil pump forces oil through the lubricating oil distribution box, lubricating oil cooler to the engine.
attached lubricating oil pump out of order: connect together lubricating oil systems of both engines at the distribution box. Connect together both lubricating oil collection tanks.
both attached lubricating oil pumps out of order: force the lubricating oil (by means of the auxiliary lubricating oil pump) from both lubricating oil collection tanks through the distribution box to the engines.
lubricating oil cooler out of order: bypass damaged cooler, both attached lubricating oil pumps force the oil through the working cooler

Cooling water:
normal operation: attached cooling water pumps force the outboard sea water through the distribution box, lubricating oil coolers, engines, blowers to the exhaust manifolds.
attached cooling water out of order: both engines are cooled by one attached cooling water pump.
cooling by auxiliary cool water pump: when both attached cooling water pumps out of order.
cooling down by hand pump: when the engines are shut down after running under high load (i.e. during alarm diving), it is necessary to cool them down by means of the hand pump
circulating the water by hand pump: used to circulate the water with anti-corrosion agent through the cooling water system (outboard sea water intake and outlet have to be shut).

Fuel oil:
taking the fuel oil by means of the external (depot fuel oil) pump: through the fuel oil hose, fuel oil meter and fuel oil transfer system to the fuel oil tanks.
taking the fuel oil by means of the auxiliary lubricating oil: the auxiliary lubricating oil pump can be used as fuel oil transfer pump, pumping the fuel through the fuel oil meter to the fuel tanks.
giving the fuel oil by means of the auxiliary lubricating oil: outboard, from the fuel oil tanks, through the fuel oil meter.
filling the fuel oil tank from the fuel oil tanks: by means of the pressurized cooling water
transferring the fuel oil from main ballast and fuel oil tank to the internal fuel oil tank by means of the auxiliary lubricating oil pump:
transferring the fuel oil from the internal fuel oil tank to  main ballast and fuel oil tank by means of the auxiliary lubricating oil pump:
draining the internal fuel oil tank by means of the trimming pump: the trimming pump can be used to drain the internal fuel oil tank by means of the auxiliary hose connection between the fuel oil compensating system and the pump.
draining the internal fuel oil tank by means of the cooling water hand pump: by means of the auxiliary hose connection between the pump and compensating system
draining the internal fuel oil tank by means of the auxiliary cooling water pump: by means of the auxiliary hose connection between the pump and compensating system


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Mar , 2017, 21:38
Great info Maciek...


Hello Mr. Tore,


I found the following in the British U-570 Report... Is this correct?



Circulating Water System
 
   
The circulating water pumps are fitted in pairs at the forward ends of each engine.  They are engine driven from the crankshafts.
 
   
2.  The main inlets are fitted at each side of the starting platform and are in duplicate, the inner valve being a sluice.  There is a common suction to each pair of pumps and there is also a common delivery pipe and a common air vessel.  A relief valve is fitted in each discharge, the water from this relief passing to the bilge.
 
   
3.  A throttle valve is fitted in the suction side in order to regulate the amount of water pumped.


Generally, was the diesel attached water pump replaceable at sea or was it a depot job?
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2017, 00:55
Don.
Below is an image of the attached double coolingwater pumps driven from the front side of the crankshaft. As you see the pumps are placed well below the floorplating and are not easy accessible. When we had the broken coolingwater pump, we were able to inspect the collateral damage and change the parts by the engineroom crew.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Mar , 2017, 01:48
Hello Mr Tore,


OK, its a double piston pump not actually two water pumps... The word "pairs" confused me!
If one piston or one set on valves fail will the pump still be functional enough to cool the engine?

Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2017, 02:15
Don.
I guess it depends on the failure as you have common discharge and no isolating shut off and common gearwheel pto on the crankshaft. I guess the capacity of the pump would be OK, but I would prefer to shut of the damaged pump completely and using other cooling alternatives.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Mar , 2017, 02:33
Hi Maciek,

I'm having some problems with the Fuel Oil: Info...

Using the Auxiliary lubricating oil pump to transfer fuel oil from one tank to another?  If you are taking fuel oil from a saddle tank, then the fuel oil goes through the tank selection valve chest then to the fuel oil valve chest and finally to the aux lubrication oil pump...  Now, what path does the auxiliary lubrication pump use to get the fuel oil back to the internal fuel oil tank? It looks like the tank selection valve chest is a one-way street, unless depot refueling where fuel only flows in the opposite direction?

Draining the internal fuel oil tanks? That U-Boat ain't gonna dive?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Mar , 2017, 03:06
Don.
Pumping fuel from the fuel/ballast saddletanks might be a problem if you use the internal fuel system as a suction system. The reason would be that the deliverypipe, now acting suction pipe, ends on top of the saddletanks to prevent watercontamination. Without a compensating waterpressure the aux fuelpump suctionpipe would end up in the air.  If for some reason you would have to transfer fuel from the saddletanks in fuelconfiguration by the aux.fueltransferpump you would use a hoseconnection possibly via the man hole.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Mar , 2017, 03:09
Hi Don,

Using the Auxiliary lubricating oil pump to transfer fuel oil from one tank to another?  If you are taking fuel oil from a saddle tank, then the fuel oil goes through the tank selection valve chest then to the fuel oil valve chest and finally to the aux lubrication oil pump...  Now, what path does the auxiliary lubrication pump use to get the fuel oil back to the internal fuel oil tank? It looks like the tank selection valve chest is a one-way street, unless depot refueling where fuel only flows in the opposite direction?

I have to correct myself.

Fuel oil:
[...]transferring the fuel oil from main ballast and fuel oil tank to the internal fuel oil tank by means of the auxiliary lubricating oil pump:
transferring the fuel oil from the internal fuel oil tank to  main ballast and fuel oil tank by means of the auxiliary lubricating oil pump:
[...]

These two lines should look as follows:
transferring the fuel oil from saddle tanks to the internal fuel oil tanks by means of the auxiliary lubricating oil pump: the pump takes the fuel oil from the saddle tanks through the fuel oil transfer system and pumps it through hose connection of the fuel oil valve chest (I guess b1 or b2) to the internal fuel oil tank (I guess the hose connected the fuel oil valve chest and the compensating system of internal fuel oil tanks (drain connections c1). The water would be removed by fuel through the test lines.
transferring the fuel oil from saddle tanks to the internal fuel oil tanks by means of the auxiliary cooling oil pump: the pump is configured to pump the water to the the saddle tanks, the saddle tanks and internal tank is connected by means of the fuel oil transfer system. Shut the cooling water discharge to the internal tank, open the vent lines of the internal tank. The oil is forced from the saddle tanks to the internal tank by means of the pressurized water.

Draining the internal fuel oil tanks? That U-Boat ain't gonna dive?

Why would the U-Boat dive? Draining the water would be the scenario to make the internal tanks empty (i.e. to make inspection).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 Mar , 2017, 03:13
Pumping fuel from the fuel/ballast saddletanks might be a problem if you use the internal fuel system as a suction system. The reason would be that the deliverypipe, now acting suction pipe, ends on top of the saddletanks to prevent watercontamination. Without a compensating waterpressure the aux fuelpump suctionpipe would end up in the air.  If for some reason you would have to transfer fuel from the saddletanks in fuelconfiguration by the aux.fueltransferpump you would use a hoseconnection possibly via the man hole.

Right. While pumping the fuel from the saddle tanks by means of the fuel oil transfer system (Treibolforderleitung), Germans simultaneously admitted the pressurized water by means of the compensating system.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Mar , 2017, 16:16
Hello Mr. Tore and Maciek,


The fuel transfer that I want to document would be from internal fuel storage tank like 1 IB. The reason for my interest is that when schnorchelling the cooling water pressure head to/from the internal fuel tanks is too high for the gravity tanks (14 mwc). So a directive was issued that when schnorchelling only the saddle tanks may be used as a fuel source to the gravity tank.


During the late war period, U-Boats with schnorchels were pretty much below the surface bound. Therefore, a fuel oil saddle tank low situation may exist, and then a the need to transfer fuel oil to the saddle tanks.


On Plan 9, internal tank 1 IB has a hose connection "b3" where the source is the internal storage tank 1 IB. If there was a hose connection between "b3" and "c" at the Auxiliary lubricating oil pump head, then could the pump transfer fuel through the tank selection valve chest and then to the saddle tanks? The cooling water pressure head already exists for the internal storage tank, and it's always available to the saddle tanks.  It looks to me like this would be sort of a refueling situation for the saddle tanks, and the cooling water in the saddle tanks would be forced to exit at the header tank overflow...


Does this drawing look OK?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2017, 02:36

Don.
I am not familiar with the German schnorchelling instructions and give my comments based on my experience. In general the internal fueloil tanks are designed for watercompensating which have many advantages. The high compensating water pressure while schnorcheling is of course a problem as the testpressure for the internal fueltanks is 8 mwc. However I don`t see the need for using the saddle ballast/fuel tanks while schnorcheling. Although your proposed system I guess would work, I don`t think it would be nessecary. What you really need is to top up the header settling/day tank in the engine room. The volume of this tank is appr. 365 liters. I would prefer to use the watercompensating system isolated from the external headertank in the wintergarten, using the handcoolingwater pump in the engine room to allow compensating water to enter any of the two internal fuel storage tanks, using the system already installed and cracking the intakevalve c1in the crossover line as per my sketch below. I estimate it would take about 1/2 hour to top up the daytank. Kindly note the external fueloil storage tanks have  reliefvalves both for overpressure and underpressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Mar , 2017, 02:41
Hi Don,

The fuel transfer that I want to document would be from internal fuel storage tank like 1 IB. The reason for my interest is that when schnorchelling the cooling water pressure head to/from the internal fuel tanks is too high for the gravity tanks (14 mwc). So a directive was issued that when schnorchelling only the saddle tanks may be used as a fuel source to the gravity tank.

During the late war period, U-Boats with schnorchels were pretty much below the surface bound. Therefore, a fuel oil saddle tank low situation may exist, and then a the need to transfer fuel oil to the saddle tanks.

I can not find the source right now, but I remember that I was reading somewhere (standing order, KTB?) that when the U-Boat was fitted with Schnorchel, the over-pressure and under-pressure valves of the internal fuel oil tanks were adjusted to make them usable  during submerged cruise.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Mar , 2017, 02:54
Hello Mr. Tore and Maciek,


Mr. Tore - how often would you have to spend 1/2 hour hand pumping water on a Gravity Tank cycle? Also from what I remember, you did not usually have fuel oil in the saddle tanks...


Maciek - the article is at  www.uboatarchive.net/U-413INT.htm (http://www.uboatarchive.net/U-413INT.htm)  and on page 19.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Mar , 2017, 08:22

Don, you are right we did not use the saddletanks as fueltanks and I have tried to remember how we transferred the fuel from the inner tanks to the settlingtank in the engineroom while schnorcheling. I guess we used the normal compensatingwatersystem, which by schnorcheling is estimated to have an additional 0,6 m WC pressure to the normal surface cruisingpressure.
The internal compensatingsystem and fuelstorage tanks have as previously stated a safetyvalve at the pressurehull intake, this valve can be adjusted, but I guess we cracked the hullvalve throttling the pressure when filling the settling/daytank at a volume of half a barrel, this was done in a short time. In addition to the intake pipe reliefvalve, each internal fuel storagetank were equipped with another safety arrangement consisting of a valvechest containing an overpressure and an underpressure reliefvalve to prevent damage to the tank.
As far as I could estimate the fuel consumption of one diesel at schnorcheling would be appr. 220 litres/hour which would mean a topping up of the settlingtank a little more than twice a watch. I think Macieks indication of seeing an info on adjusting the safetyvalves migth be correct as we are talking about minor pressures.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Mar , 2017, 01:49
Hello Mr. Tore and Maciek,


I have done a major rewrite of Skizzenbuch where information has been updated and the pages are arranged to follow a logical sequence. I have backgrounds for all the plan pages of either photos or colors.


The latest version of Skizzenbuch 11 x 17 - M.pdf has been uploaded to Dropbox.


Herrn Klaus Mattes and Jak P. Mallmann Showell are working with two German Museums and several German U-Boat Interest Groups about Skizzenbuch.  They seem to be impressed with the scope and depth of our work.  I may have more info in a week or so.


Regards,
Don_


PS - Klaus Mattes wrote a book "Die Seehunde"...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 16 Mar , 2017, 11:27
Great book, I have it in my little U-boat library.  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 17 Mar , 2017, 03:22

Don Prince.  Is there any way i could buy an early access for Skizzenbuch from you?
I could really use it as a technical reference for my game. Originally i planned to wait until spring and buy from publisher, but that option is not there anymore. Having an access to Skizzenbuch would help me make a better game. I would also be happy to credit your name and book in my game if this is something that would be an interest for you.

VIC20. We spoke over email 2-3 years ago when i asked you for some technical advice. I have not forgotten my promise. If the game quality holds up from your perspective and if you wish, i can credit your name also.

Tore and Maciek
Would like to make you an exact same offer. Would be an honour to have your names also there.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Mar , 2017, 15:34
Hello Karel,


Give me about a month, Klaus and Jak are working with several German U-Boat support groups and two museums promoting Skizzenbuch. I don't believe there will be any legal distribution issued because I am not asking for any monetary compensation for Skizzenbuch; my work stands on its own merit! Several years ago when I started compiling Skizzenbuch, it was intended only for my personal library; I am not the U-Boat expert like Mr. Tore and Maciek. I purchased a leather covered metal post binder for my library with gold lettering on the front cover. The binder determined the 1.75 inch spacing on the 11x17 inch binding side page layout.


My requirement: The Skizzenbuck PDF file is not protected form modification. This was done intentionally, so Mr. Tore and Maciek could modify Skizzenbuck if they so desired. However, I have only made changes to the Skizzenbuch 6 Microsoft Word files which are converted to PDF files. and then the PDF files are merged into 1 PDF file. If I give you access to my Dorpbox folder account which contains the "Skizzenmbuch 11x17 - M.pdf" file, then this file will not be distributed without my permission.


Later, I plan on purchasing "CopySafe" PDF protection software (very expensive) which encrypts the PDF file and embeds a viewer in the file. Also, it provides the PDF author with a host of other options.


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Mar , 2017, 20:00
Hello Mr. Tore,


I believe it was mentioned that the cooling water pump in the e-room had some fittings to allow the introduction of anti-corrosion oil...  I can see a direct path through the cooling water valve chest, but it looks like the anti-corrosion oil only makes one pass through the pipes and the diesel engines. Then it goes through the cooling water system; the mufflers and to the header tank and out to sea.  Is that correct? How often was the anti-corrosion treatment done?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Mar , 2017, 03:03

Don.
In spite of a few pipebends having severe corrosions I can not remember we used anticorresion oil. I believe the oil was pumped into the coolingwatersystem by the coolingwater handpump stb side in front of the mainengine, a spesial armed oilresistent hose was used, diameter 38mm  and length about 2 meters. Below is an image showing the system, as the plate 13 for the GW engine is not showing a correct system, I include the plate 13 a which is the  MAN system however the anticorrosion oil inlet is the same for both enginetypes. . As far as I know the anticorrosion oil came in a barrel and the end of the hose was put in the barrel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 20 Mar , 2017, 09:07
Don.

Thank you. I can wait a month, no problem. I am shifting some stuff around and work on sound and lighting for a while and shall return back on to systems when i have access to Skizzenbuch.
Just let me know in private message if you are ready. I am really excited for this and thank you again, this makes my life so much easier.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Mar , 2017, 17:08
Hello Mr. Tore,


It looks like they could hand pumped anti-corrosion oil into the cooling water valve chest while the diesel engines were running. The hand pump's pressure head would be greater than that of the two attached diesel cooling water pump's pressure head, so the anti-corrosion oil would be mixed with the cooling water as it is pumped into the cooling water valve chest; then its piped to the lubricating oil coolers and on to the diesel engines.


Is my summery correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2017, 01:40

Don.
I guess your understanding of the anticorrosionsystem is correct. The procedure was to start the engines and let them idle, then "injecting" the anticorrosion oil by the hand pump. The oil used was an emulsifying oil having the German naval specification Zd M17. The "contaminated" coolingwater could be drained via cock f1 to the dirty luboiltank aft of the luboil systemtanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2017, 21:48
Hello Mr. Tore and Maciek,


I have made some additional changes to Skizzenbuch and added an "Index." The new file is in my Dropbox account folder...


Skizzenbuch 11 x 17 - M + I.pdf


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2017, 02:33
Don.
I have started to look through you latest Skizzenbuch and it strikes me you are gradually going into more details of the VIICs which might require an upgrading of the prevous work done. While reading page 122 dealing with the engineroom exhaustsystem I guess the exhaustblowing of the ballasttanks has been a bit neglected. The outer main exhaustvalve has a task of being a damper,  operated by the engineroomcrew to adjust the exhaustback pressure of the dieselegine in operation. I have made an image on the subject. Kindly note that the outer exhaust system including the branch  to the exhaustblowingpanel is turned 90 degrees in relation to the inner system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Mar , 2017, 04:09
Hello Mr. Tore,


Thank you for taking the time and looking at the latest version.  I will be glad to make any changes that you deem necessary or should be changed. I know I have made many changes throughout the book form the discussions I had with you and Maciek. It always good to have a 2nd opinion by an expert! Also, I have made changes to the electronic documentation that Maciek provided (and we worked on) to get a more precise English wording. I sure hope that I have not made the info wrong or misleading.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Mar , 2017, 04:43
Hello Mr. Tore,


The outer exhaust grinding system and muffled run horizontal above the pressure hull (I believe that is correct).  Does the 90 degree rotation mean this is related to the inner exhaust grinding system.  If I rotate the inner exhaust grinding system 90 degrees counter clockwise, then the exhaust pipe coming from the diesel engine would connect to the inner exhaust grinding system at the back side near the pressure hull? (that looks logical) But I need your advise on that???


I don't want to change the middle drawing to reflect the physical 90 degree turn because we would loose the clarity of the information presented. However, I will note the physical equipment relationship for accuracy.


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2017, 05:46
Don.
I made the sketch showing the inner main exhaustvalve atwartship and outside the pressurehull, the exhaust flapvalve (damper) and  silencer alongship, thus turned 90 degrees, just to make it easier to understand the working. The exhaustdamper is primarerly used while exhaustblowing the ballasttanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2017, 08:22

Don.
On page 143 of your Skizzenbuch I am afraid you have misunderstood the luboil system as you have connected the gravity drain from the main engine to the suctionside of the stb.attached lubeoilpump. I guess a description of the luboilsystem would clarify the matter.
The luboil system is based on two independent systems, for each engine, being able to  interconnect if needed. It works on a dry sump principle, meaning each engine have a separate systemtank under the engine. Below is an image of the normal and alternative operations. Normal operation of the port engine is as follows: the port systemtank holds the lubeoil for the port engine and the attached lubeoil pump takes its suction (green) via a normal NR footvalve in the tank. The discharge ( red having a reliefvalve with drain (blue) to the systemtank), goes to the distribution box between the engines passing a NR valve b. Valve a1 is open and allows the oil to flow via the main oilfilter with differentialmanometers to the port oilcooler having a dirty oil pipe(blue) via cock f to the port systemtank. After the cooler the oil passes a selector cock c1, in this case normally selecting the port engine. After that cock is a small pressureline to the servomotor for the governor on the camshaftdrive side (aft) of the engine. The servomotor shuts down the engine in case of lubeoilpressure failure and assists the governor in moving the fuelrack. The discharge pipe continues on the front of the engine to a pressure reductionvalve,( rembember the small red wheel?) reducing the pressure from 3kg/cm2 to 1,5 kg/cm2 before it branches off to the main bearings, camshaft drive and supercharger. When the lubeoil has passed the enginecomponents, gravity takes the oil through drainpipes (blue) to a selectionbox to port or stb systemtanks, where port in this case, normally is selected. The attached lubeoilpumps can not take suction via the drain system.
In case of an attached luboil pumpfailure, the quickest and easiest way of an alternative would be to use the aux. electric driven lubeoilpump. The system on my image is self explaning, I guess, and as a last alternative you are able to use the stb. attached lubeoil pump, which system you`ll find on my image as well.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Mar , 2017, 21:55
Hello Mr. Tore,


I have a lot of work to do... I have a question about the Pneumatic Motors that drive the valve grinding for the external exhaust valves... Are the pneumatic motors started automatically when the hand wheel is turned to close the exhaust valve, or was some other action required to start the pneumatic motors?


Also, I don't believe I see any reference to the pneumatic motors on the mechanical or electrical German shizzenbuck PLATTs either?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Mar , 2017, 01:13
Don.
The pneumatic grinding motors for the outer exhaust dampers were connected to the LP system as German plan 12 shows on my image below. There is no automatic starting, just  opening of the small LP air valves as shown. As prevously told, when diving, the dampers had to be fully shut and you experienced always some carbon deposits on the seatings. Our procedure was to start the grinding at some 3-4 meters to obtain sea backpressure on the valve disc for better grindingeffect. As the air used was released into the engine room, you had to limit the grinding as much as possible to prevent excessive overpressure in the submarine, buggering up the reading of the gauges.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Mar , 2017, 19:56
Hello Mr. Tore,


The cooling water pump in in the aft e-room...  Was there a hardware setup that would permit anti-corrosion oil to be admitted into the seawater to the cooling blowers, e-motor bearings, thrust bearings, etc.?


By the way...  What does the abbreviation "NR" stand for in your write-up about the lubrication oil system?  "Normal" - something, I guess?


Why is there a return line through cock f to the collection tank? Would something be wrong with the oil cooler when using this line?


What is the big box the the left in the schematic? Is that the pump that is driven by a rocker arm that dispenses lube oil through small tubes to those hard to reach areas?


What is the function of valve g? and what is the return line directly ti the left of the pump for?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2017, 03:15

Don.
I don`t think there is an anticorrosion oil "infusion" in the E-room coolingwatersystem, however it is an anticorrosion connection at the stb engine groupexhaustvalve cooling system as indicated on the image below. The yellow line indicate the system entering the Junker compressor cooling water system. It is a possisbility to connect this system to the E-motors cooling systems shown by the broken yellow line as well as a more doubtful purple broken line to the e-compressor. The broken lines indicates I am not sure of these systems. Kindly note the E-room system is copied from the MAN coolingwater system as the plate 13 of the GW system is of bad quality. Both systems in the E room are the same.
NR stands for non return eg NR valve is a non return valve.
Cock f on the pipe from the lubeoilcooler is for draining the cooler, the pipe connects with the other draining pipes like safetyalve and reducing valves.
The rectangle on far left in the lubeoilsystem is the supercharger.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2017, 03:41
Don.
I forgot your last question. Valve g and the small branch off pipe in this system is for lubeoil to the attached gearpump in those cases the pump do not work, but still is attached idling.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Mar , 2017, 03:53
Don.
The two drainlines in front of the engine is 1. the forward sumpdraining and 2. the draining of the pto lubrication of the attached equipment in the front of the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Mar , 2017, 20:24
Hello Mr. Tore,


Thank you for the info... There looks to be a 2nd thermometer and an oil pressure gauge on the oil pressure line after the oil cooled. Do you know their location? Photo?


Schematic attached...

Also, I have been reading about the difference between oil reducing valves and oil safety valves.
1. The reducing valve uses a spring and hand wheel to set the output pressure to a fixed value. However if the source pressure increases, then so does the output pressure.
2. The safety valve uses a spring and hand wheel to set the limit for its out pressure. If the source source pressure increased, then the excessive oil is drained off to hold the output pressure limit.


Valve h is definitely a safety valve (h          SICHERHEITSVENTIL )


Valve d is listed as a pressure reducing valve (d          DRUCKMINDERVENTIL)
 but has a drain line which makes me believe that the Germans were actually using a safety valve as a reducing valve - most likely to eliminate back pressure in the line.


What do you think?
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2017, 01:52

Don.
The placing of the thermometers are indicated on the image below. Normally the temperature readings were done locally, except the cylinder exhausttemperatures, whereas the pressuregauges were assembled in an instrumentpanel for both engines placed high up between the engines, on the museums U 995 almost hidden behind a fluoroscent light tube. 
A pressurereducingvalve or more correctly pressurecontrol valve, is placed in the pipesystem to control the operating pressure in the system. The pressurecontrol valve is designed to open or shut to modulate or regulate the operating pressure. A pressure relief valve or safety valve is designed to open fully at a preset value and then shuts or resets when the pressure falls below the design maximun pressure. You should never used a pressure reducingvalve as a pressure reliefvalve to protect a structural integrity of a system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2017, 02:25
Don.
Below is a crossection image of a oilpressure reduction valve. As you see it is an intricate design with hydraulic ballancing bores having a drain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Mar , 2017, 02:50
Hello Mr. Tore,


OH!!! Then the pressure regulating valve is a double chambered valve with a drain...  very interesting! I was only reading about a single chambered regulating valve...


The safety valve attached to the oil pump's output...  The diesel engine's rpm will increase with speed. Therefore, the oil pump's pressure will increase as well.  This makes be believe that the oil pump cannot over pressurize the lube oil system and pop the safety valve. The only way to pop the safety valve is to have a valve shut that should be open for the lobe oil flow (a screw-up) or something got blocked like a filter or cooler.  Then the safety valve would pop and dump the oil back into its collection tank...


Am I making any sense?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2017, 02:50

Don.
You impression of the Germans used the pressure reducing valve d as a safetyvalve is probably based on a misunderstanding reading the pipescheme. As the drawn drainpipe from the valve looks rather big it is actually a very small drainpipe which by no means would be able to drain the system. It merely takes the small leakages from the ballancing bore in the reducing valve as can be seen on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Mar , 2017, 03:05
Hello Mr. Tore,


lets assume there is a plugged oil filter... If you are cranking the engine on air, then is there is no lube oil going to the engine. Would there be anything that notified the mechanic of this problem before the safety valve pops?  Would they ever get to the point of injecting fuel?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 26 Mar , 2017, 03:38
Don.
Humans can always overule the interlocks. You are able to crank the engine by air without luboilpressure as well as starting the engine without coolingwater etc. The fuel rack can be moved irrespective of the governor servo.  The system is based on qualified engineers operation and it is a limit as to how many interlocks you want to install and how much complications you  would introduce.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Mar , 2017, 02:42

Hello Mr. Tore,


For the GW diesel engine - would it be fair to say the safety valve works as follows:
1. The safety valve provides for high pressure relief seen at the lube oil pump head.
2. If the oil filter was getting plugged then the oil pump would see an increase in back pressure.
3. At some point the safety valve would reach the 'Cracking Point" where there would be a small flow of lube oil to the collection tank. The cracking point is generally far below the popping point.
4. If the oil filter problem continues to get worse, then at some point the safety valve will do a full vent flow or "Pop."
5. The pipe for the safety valve is not huge, but it should be large enough to create a pressure drop.
6. The safety valve is designed so that it will not recover from a full vent flow (Pop) until the pressure went down below the cracking point.
7. The lube oil pipe to the servomotor and the governor should sense the pressure drop and react by shutting down  the diesel engine.


The MAN diesel engine uses the safety valve to short the lube oil pump output to the lube oil input. I believe they are achieving the same result (a pressure drop). I have the schematics for the type IX U-Boat and the MAN 9 cylinder diesel engine and it does not have a reducing valve 1.5 < 3.0 atu in the lube oil system schematic.


I have done a lot of research on the safety valve...
 
If I assume the the GW 6 cylinder engine is at mid range rpm, then the attached lube oil pump pressure head is about 3 atu... Is that correct?


The reducing valve at 1.5 < 3 atu will create some back pressure when reducing its pressure output without an adequately sized vent line, but I guess the system can handle that back pressure with pipe lengths and passing through various components.


What do you think?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2017, 06:43

Don.
The attached lubeoilpump is of a gearwheel type meaning a positive displacement pump,  delivering a fixed volume pr. revolution. All such pumps for non compressible liquids require a safety valve to relieve the full max. volume to prevent damage in the event of fi. a shut discharge valve. As the pump is a positive displacement pump the safety valve has to open proportionally with the pressure. Generally such a safetyvalve is an integral part of the pump.
The servomotor of the governor forces the fuelrack to stop in the event of a pressuredrop below a preset minimum luboilpressure, irrespective of the cause.
Allthough they are drawn slightly diffent, there is in principle no difference between the GW and MAN systems. Below are the two systems, both system have an attached gearpump having a discharge pressure of 3 kg/cm2 and a reduction valve prior to the engine inlet to 1,5 kg/cm2. A branch off to the governor servo on the MAN engine is marked trieboelv.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Mar , 2017, 20:14
Hello Mr. Tore,


Thank you for all your patients...  I have always tended to ask questions to gain a better understanding as to how things work (a personal flaw I guess)?


In order to access and change valve settings in the lube oil distribution valve chest, it looks like a center section of the floor panel must be raised. Was this section of the floor panel hinged for ease of access? Perhaps that shinny steel screwed down floor plate on U-995 is not original?

Also, when you are injecting anti-corrosion oil into the cooling water valve chest, I believe you would select each engine side separately.  Is that correct?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Mar , 2017, 00:02
Don.
Don`t worry, I guess asking questions is an instrument for learning. The floorplatings were raised in the way of the lubeoil valvechest between the engines as you can see on my image below. The floorplatings have been changed on the museum U 995 as you can see and they differ from the original as shown on the top photo. I don`t think the platings were hinged.
You could flush the anticorrosion oil in many ways including each engine separately.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Mar , 2017, 19:18
Hello Mr. Tore,


I noticed something on your upper photo just posted...  Those pipes had the 3 band markings like the color bands on Plan 3. That would make it much easier to troubleshoot problems.  It looks like when U-995 was refurbished for the museum that the pipe color bands got painted over!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 28 Mar , 2017, 19:32
Hello Mr. Tore,


I noticed something on your upper photo just posted...  Those pipes had the 3 band markings like the color bands on Plan 3. That would make it much easier to troubleshoot problems.  It looks like when U-995 was refurbished for the museum that the pipe color bands got painted over!


Regards,
Don_

You are correct, most of the Colour Bands have be  painted over! There a few colours bands left in the Control Room also. It has taken me quite a while to figure out the correct colour band.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Mar , 2017, 01:23

Don and Simon.
I guess the museum U 995 being short of funds are depending upon a lot of voluntary maintenance work, unfortunately a lot of painting is done without proper guidance. This result in overpainting items which sould not be painted at all. I guess the worst case is in the engine room which got red spot all over, blue valve pushrods which never was painted and the moving fuelrack including the HP fuelump rods which are ever moving items and  rather should have lubrication than a thick layor of glossy green paint.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Mar , 2017, 02:28
Hello Mr. Tore and Simon,


The US Navy deck personnel (Swabbies) had an old saying "If it doesn't move, then paint it!" I guess the diesel engine wasn't running at the time... So, we now see what happened!!! Ha ha..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Mar , 2017, 02:37
Hello Mr. Tore,


FYI... I did find a partial image of the Q Tank muffler.


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Mar , 2017, 04:37

Don.
Very good I guess we now have an image from two angles.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Mar , 2017, 23:22
Hello Mr. Tore,


If a U-Boat makes a very deep dive and the pressure hull will then be compressed. Then, when the U-Boat resurfaces will the pressure hull stay compressed because there is no internal pressure to expand the pressure hull back to its original size?


If the pressure hull steel flexes inward between the round pressure frames, then I could visualize a return to the original displacement. However, as I look at U-995 there are some dimples here and there...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2017, 01:24

Don.
Normally the steel tensile strength of the pressurehull expands back to its original shape, however if the steel is subject to stresses exceeding the tensile strength you arrive into to the steel yield point and the steel begins to flow which means it would not retract to the original shape. The dents you see on the museum U 995 are primarily dents in the weaker part of the saddle tanks which migth derive from mooring collision. On some surface vessels hullplatings you migth see dents between the frames which might derive from weatherbeating or weldingstresses. If you see the pressurehull of a submarine you normally would`t  see such dents. A lot of modellers love to imply such dents, known as canning, I guess this is overdone particulary on the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Mar , 2017, 03:34
Hello Mr. Tore,


When docking and during maintenance - if the fuel oil transfer pump was used to drain the fuel storage tanks, and no diesel engines are running so this source of water cooling compensating water is not available. How would they get the fuel oil from the storage tanks. The transfer pump is trying to draw fuel oil from the top of the tanks, I don't see what pushes the oil up??? unless they use the Auxiliary water cooling pump to force water through the diesel engines and then on to the header tank....

this issue was discussed on page 75 of Skizzenbuch.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Mar , 2017, 05:29
Don.
In the unlike event of a major docking/repair with full fuelbunker tanks, the easiest way to empty the  fueltanks would be to use the aux, coolingwater pump to pressureize the compensating system as indicated on the image below, prior to entering the drydock. If this is not done while afloat, you might use a hose suctionconnection on the aux coolingwaterpump to a watersupply (yellow). The last oportunity would be to use the aux. luboil pump hose connection via the manholes.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Mar , 2017, 20:03
Hello Mr. Tore,


U-93 through U-97 had 2 e-compressors
U-98 and above had 1 e-compressor and 1-Junkers compressor


Did U-92 and below only have 1 e-compressor?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2017, 00:16
Don.
As you know the VIIC was a further developement of the VIIB, the last VIIB submarine was commissioned in 1941 I guess.  You had an overlapping periode when the VIIC was introduced in 1940. I assume the first VIICs had two E compressors as the VIIBs and when the Junker freepiston compressors were introduced, they had quite some trouble related to the exhaust backpressure resulting in various exhaust outlet alternatives. In the transition periode the  VIIC boats U 93 through U 97 were equipped with two e-compressors. The highest pennant no. of the VIIB class was U-102, but it is no relation with the German pennant no. and commission year.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Apr , 2017, 15:43
Hello Mr. tore,


In 1943 the Germans moved the hand wheel for venting the bow buoyancy tank from the forward torpedo room to the forward control room pressure hull above the hatch on the starboard side.


This was a significant and intentional change... I assume that the Germans wanted to vent the bow buoyancy tank to decrease the diving time; especially on a U-boat with the wider Atlantic bow. They would not need to vent the bow buoyancy tank on a standard dive, but in an Alarm Dive it may be advantageous...


In order to keep the horizontal balance, then I assume they would vent the aft buoyancy tank as well. The bow buoyancy tank would not need to be blown when surfacing because of the bow angle and height and with the open slots at the bottom of the tank; it would naturally drain. The only issue would be blowing the aft/stern buoyancy tank in this scenario, and that should be a normal function for the aft torpedo room crewman who have to assure the aft buoyancy tank is blown before starting the Junkers air compressor...


Comments?

Where is the stern buoyancy tank blowing valve located it the aft torpedo room?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Apr , 2017, 01:14
Don.
I guess the developement of the buoyancy tanks is a bit more complex and has to be seen in conjunction with the VIICs developement from the VIIBs. When the VIIC was designed they lengthened the pressurehull to be able to accommodate more equipment. At the same time they were able to introduce the Untertriebcelles (Q Tanks) in the saddletanks. At the time these changes were made a submarine was still a surfacevessel able to dive, rather than a true submarine, and as the radar was still not an instrument regulary in use surface cruising was done to and from the battlefield and an improved surface condition was neccesary. As a concequence of the improved surface behaviour, the buoyancy tanks were a problem as they increased the "surface resistance" when diving, which lead to filling the Q tanks while cruising on the surface to overcome the surface resistance in the event of crashdiving. In case of bad wheather, this would make life hard for the people on the bridge and empty buoyancy tank as well as a later introduced Atlantic bow  would improve the matter. It is important to emphasize that the buoyancy tanks are not ballast tanks but merely tanks for surface improvements and do not take part in the diving/ surfacing procedure thus the are to be considered as free flood areas when diving.
I agree with your conclusion on the blowing of the buoyancytanks as well as the aft buoyancytank blowing when operating the Junker compressor. As you know an interlock was installed in the Junker exhaustsystem preventing to open the exhaustvalve unless the vent for the aft buoyancy tank was shut.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Apr , 2017, 21:41

Hello Mr. Tore,


I don't believe there is any need to blow the stern buoyancy tank if they vented the Atlantic Bow buoyancy tank because the buoyancy tank's effect on the longitudinal balance becomes insignificant with depth.


Bow Buoyancy Tank Vol (m3) - Versus Depth (m)       Stern/aft Buoyancy Tank Vol (m3) – Versus Depth (m)
                 8                                  sea level                                       4.28                               sea level
                 1.34                             50                                                 0.72                               50
                 0.73                             100                                               0.39                               100
 
At 100 meters depth, the volume of the air in the aft buoyancy tank is 0.39 m3 and this calculation has not considered the volume change due to cooler water temperature with depth (reduces the volume again)!


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Apr , 2017, 02:17
Don.
As I said before the buoyancy tanks are not ballasttanks and do not participate in the diving and surfacing procedure, when  diving and surfacing the vents are open and the tanks are to be considered as freeflood areas. Surfaced they are elements in reducing the pitching of the submarine by shutting the vents.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2017, 03:03
Hello Mr. Tore,


Do you or Maciek know which valve in the aft torpedo room is used for blowing the aft buoyancy tank?


Also, what is this hand-wheel for in the attached photo in the red circle?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2017, 04:01
Hello Mr. Tore,


On page 420 in Skizzenbuch you are talking about a uhistoria.com image...  Where is this image?


"The linkage consists of a bell crank lever which snaps the cones in a locked in position. On the u-historia.com photo you see the worm rod and the piston rod fixed to a yoke having two guide rods. At the ends of the guide rods are some peculiar "nuts." These are spring loaded end stoppers; when the linkage snaps into position they push the actuating lever a fraction back to release the engagement at the shaft slide to prevent a possible hot running."


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Apr , 2017, 07:11
Don.
The U historia images are found on the U historia homepage, look to Visita Guida then Sistema Embrague which is the mainengine clutch. Since I wrote my comments on the clutches I got hold of Falos photos which are at least as good if not better. A small correction could be nessecary with regards to the hand operation of the clutch. I introduced a key and a sliding slot, as Falos images are better I discovered a locking bolt which might be used to fix the travelleing nut to the yoke assembly in case of handwheel operation.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Apr , 2017, 07:22
Don
Blowing of buoyancy tanks. I cannot find the LP air valve to the stern buoyancy tank. The buoyancytanks were not connected to the tankblowing system, but had a branch off from the ordinary LP system, like weedblowing and mainengine clutches, if you have images showing the LP pipes from the aft engine room it might be possible to trace the valve for the stern buoyancy tank. The handwheel in the red circle I cannot identify, may be Maciek has a clue.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Apr , 2017, 10:19
Tore, what means LP?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 07 Apr , 2017, 10:54
Tore, what means LP?


I will answer this question: LP means low pressure air.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Apr , 2017, 11:40
Thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2017, 14:49
Hello Mr. Tore and Maciek,


The hand-wheel for operating the stern buoyancy tank vent valve; it's position (between 6th and 7th frame) corresponds with the drawing:



http://www.uboatarchive.net/U-570/U-570DTPlate28.jpg (http://www.uboatarchive.net/U-570/U-570DTPlate28.jpg)


That means that the level near the Junkers exhaust valve (and interlocked with it) is not for operating the buoyancy tank vent valve, but for something else. Moreover, this lever (as well as exhaust valve) is located between 7th and 8th frame) and it does not match with the plate:


http://www.uboatarchive.net/U-570/U-570DTPlate28.jpg (http://www.uboatarchive.net/U-570/U-570DTPlate28.jpg)


So it has to be for something else. It is definitely interlocked with exhaust hull valve. I guess maybe it is some external flap of the exhaust duct?


1. The hardware in U-995 indicates the stern buoyancy tank hand-wheel still exists and is operational.
2. Linkage between the lever actuator and the stern buoyancy tank hand-wheel looks doubtful.
3. What is the lever actuator/interlock function?
4. The interlock lever drive shaft goes external to the pressure hull to control something?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Apr , 2017, 03:42
Hello Mr Tore,


I have taken what you previously provides and made some changes...



Drawing attached
 
1. 1st State - Junkers compressor not active - Exhaust flap valve shut and the grinding plate valve is shut (submerged)
2. 2nd State - transitional
3. 3rd State - Junkers compressor active - Exhaust flap valve open and the grinding plate valve is open and the diesel exhaust is directed to the external water cooled muffler

What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Apr , 2017, 03:26
Hello Mr. Tore,


I have been working on the Junkers exhaust system and came up with what I believe may be the internal drive of the outer segment. This doesn't look to be a difficult gearing design since I had to work on NCR mechanical cash registers when I was 22 years old.


However, I have ran into a problem with the exhaust system.  It looks like the intermediate disk up near the upper pressure hull is out of time or sync...


I will attach a photo and the problem is marked.


Please advise...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Apr , 2017, 14:52
Hello Mr. Tore,


I believe I know what happened to get the upper drive segment out of sync...  The hand-wheel provides a great mechanical advantage when applying force to its drive shaft. Then you can multiply that force times 10 with the final stage gear drive.


The final stage drive gear is taper pinned (heavy) to the drive shaft along with the lighter upper drive segment (smaller) taper pin. If for some reason the lever that locks the intermediate gear was not moved to the unlock position, and there was driving force applied to the hand-wheel, then you have a situation.  The force applied to turn the final stage gear, is applied to the segment meshed to the intermediate plate gear which can not be turner and will result in the small taper pin holding the segment to the drive shaft to shear.


Now, the relationship between the final stage drive gear and the upper drive segment no longer exists and there is no drive to the segment (it's broken)!!!


What do you think?


Regards,
Don__
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Apr , 2017, 16:09
Hello Mr. Tore and All,


If you zoom on my image, then it looks like the intermediate wheel is missing some teeth.  If someone has a better resolution image, then this can be confirmed...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Apr , 2017, 16:24
Hello Karel,


I will provide you with a link to Skizzenbuch once I get the junkers exhaust issue settled.  However, this version of Skizzenbuch will be in a PDF format and is not copy protected.  Therefore, on the condition that you will not distribute this version, then you are welcome to it.  Eventually I will get a program called "CopyProtect" which will allow the distribution of a PDF, but under the writers control (it encrypts the PDF and comes with an embedded viewer)...


The next time I post a new version of Skizzenbuch to my dropbox folder, then I will send you a link.  Please send me an email so that  I may use it to send you the link.


My email address is:


donprince5207@comcast.net


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Apr , 2017, 00:24
Hello Mr. Tore,


I have worked on an Junkers exhaust system based on the outer photos that are available...  Please advias as to your opinion which is highly valued.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 13 Apr , 2017, 01:32

Hello Don.This is wonderful news. I have sent you an email.


Thank you

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Apr , 2017, 02:03
I posted the latest version of Skizzenbuch 11 - 17 - M + I.pdf in the dropbox folder.


I expect there may be some changes after Mr. Tore and Maciek review the latest version.


Regards
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Apr , 2017, 16:47
Hello Mr. Tore,


The GW diesel engine had an RPM counter that looks to turn over at 1,000,000 rpm...  If the diesel engine was running at an average of 390 rpm, then it would take about 42 and 3/4 hours for the counter to turn over.  Was there some sort of a maintenance scheduled at a turn over? If not, then what is the purpose for this counter?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Apr , 2017, 08:22
Don,

to be strict, this is revolution counter, not RPM counter.
In my opinion, the turn-over value indicates that it was supposed to read off every 24 hour, and then the values were sum-up.
I cannot give you any schedule-periods, but engine revolutions as well as working ours were recorded in the KTB Maschine.
Some U-Boat KTBs had attaches: radio logs, maps, torpedo reports or engineering logs (KTB Maschine). In the engineering logs were recorded all information related with mechanical equipment of the U-Boat (among the others data related with diesel engines: fuel consumption, working time and so on). At the uboatarchive.net website are available some engineering logs.
For example:
http://www.uboatarchive.net/U-107/KTB107-6KTBMaschine.htm
PortMotorStbMotor
DaysHoursMinDaysHoursMin
Total operating time since commissioning:22018332211530
Total operating time during the last patrol:37737372215
Revolutions since commissioning:8314859684922374
Revolutions during the last patrol:1339818014144920

http://www.uboatarchive.net/U-518/KTB518-2KTBMaschine.htm
stb engine
operating time since commissioning: 2603 hours 4 min
operating time during last patrol: 943 hours 56 min
revolutions since commissioning: 33,349,060
revolutions during last patrol: 11,341,510

port engine
operating time since commissioning: 2598 hours 10 min
operating time during last patrol: 960 hours 28 min
revolutions since commissioning: 36,043,720
revolutions during last patrol: 11,412,440

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Apr , 2017, 10:00
If you zoom on my image, then it looks like the intermediate wheel is missing some teeth.  If someone has a better resolution image, then this can be confirmed...

Maybe this photo is better.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 Apr , 2017, 14:23
Hi Gentlemen,

while looking through the KTB Maschine, in this document (http://www.uboatarchive.net/U-107/KTB107-6KTBMaschine.htm) I have found the following (the section regarding the issues with Junkers compressor):
Quote
After disassembly of the internal exhaust gas valve, it was found that the seat of the valve was burnt or ground out over half of its perimeter.  Repair was not possible by on board means.  The external valve is tight.

This fragment indicates that Junkers compressor exhaust hull valve consisted of internal and external part (what was not so obvious for me).
Maybe it looked as follows: in the early years of war, both valves were driven by two hand-wheels. This hand-wheels are visible at this photo taken on U 570:
(http://uboatarchive.net/U-570/U-570Photo31.jpg)
Left hand-wheel drives the internal valve (water-cooled casing with thermalinsulation) while the right hand-wheel drives external valve (and that's why it does not have thermalinsulation, it is just a shaft going through the hull). Both valves are driven by hand-wheels and are fitted with valve state indicators. To close or open the valves, many turns are required, so one can recognize them as "slow-working" valves. That means that it took long time to open both valves fully, and before it was done, seawater breaks into the exhaust system.

When German recognized this problem, in the later U-Boats (like U 995) they interlocked the external and internal valves in such way that external flap could only be opened when internal valve was opened previously. In this design, hand-wheel driven, "slow-working" internal valve would be opened fully, and only then, external flap could be opened by "fast-working" lever (this lever could be rotated by ~330 deg, so it has lower radio-gear, requiring a greater force, and that's why long lever was provided). In the same time when the external flap was opened quickly, the Junkers compressor was started, and exhaust pressure did prevent water intrusion.

Generally, this idea is concurrent with Don's idea presented in his post (http://models.rokket.biz/index.php?topic=921.msg20466#msg20466).

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2017, 07:06

Don and Maiek.
Regret I had to leave my mailbox for a while due to some family matters. I am just home for a few days before I leave up to my summerfarm for the year on late tuesday. My problem is then I am not sure when I get access to the internet, hopefully in a few days, may be wednesday/ thursday  April 26/27, sorry about this. I have briefly read the various proposals on the Junker and as I remember some of the " designs" I made on the exhaust system was, as I mentioned at the time, pure guesswork in lack of documentation. In the meantime Maciek has come up with an interesting image which together with Dons  sketches might give a better understandings on the matter. I shall look into this again, just a preliminary remark Don, the hull exhaustvalve normally shuts having the seapressure behind the valvedisc which means, I guess, the valvedisc on you sketch should be in the top chamber on you image.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 16 Apr , 2017, 12:32
Hi Tore,

it's great to hear from you again.

Gentlemen, if I recall correctly, some time ago we had discussed briefly (however I cannot find particular posts) about safety pins (or safety seals) securing the vent valves from being accidentally opened.

I have found few photos taken aboard of HMS Graph. They are showing the MBT 5 vent hand-wheel secured with locking pin, and MBT 3 port vent lever secured and unsecured.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2017, 13:34
Thank you Maciek.  Nice images of the vent locking pins.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2017, 18:03
Hello Mr. Tore,


 I hope all is well with you and your family... Happy Easter!


I thought about the location of the exhaust valve plate and the shutting direction.  There were three reasons for this particular proposed design:


1. I drew it with the shaft raising upward and shutting the valve because when you turn a valve clockwise the hand-wheel and valve stem would generally move into the valve housing to shut the valve (grind the valve plate and seat in this instance). Also, the valve was mounted upside-down in the exhaust system.


2. When the hand-wheel is turned counter clock-wise to fully open the plate valve, then the rotating hollow valve stem shaft moves downward into the housing, and is not exposed to the exhaust heat or a carbon buildup.


3. When the external flap valve is shut, then it has the external water pressure applied to it. Therefore, the exhaust plate valve should not experience these water pressures.


What do you think?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Apr , 2017, 00:11
Thank you Don.
If you look at the main engine exhaust hullvalves you see the principle, and I guess it is possible they followed the same system on the Junker exhaust. Allthough the outer Junker exhaust valve was not used as a damper, you would experience carbon deposite on the outer exhaustvalve causing leakages as the Junker was a two stroke diesel and more susceptible to carbonization. I agree with your philosophy of shutting valve by turning the handwheels clockwise. I guess we could overcome that by using anticlockwise threads operating the valvestem.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Apr , 2017, 21:22

Hello Mr. Tore,


After reviewing Maciek's info from a U-Boat KBT log which states the following:


"After dis-assembly of the internal exhaust gas valve, it was found that the seat of the valve was burnt or ground out over half of its perimeter.  Repair was not possible by on board means.  The external valve is tight."


It would be virtually impossible to take apart the exhaust valve system and separate it from the outer exhaust casing if the exhaust valve plate extended up into the upper chamber; the valve plate would have to move through the valve seat.


When the valve seat was damaged, they could see that burned and worn out areas. The valve seat must have been face downward because I don't believe they would have disassemble the outer exhaust casing.


However, they could separate the lower exhaust valve system from the upper pressure hull and exterior exhaust casing to inspect the valve plate and the valve seat from inside the pressure hull.


What do you think...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2017, 01:23

Hello Mr. Tore, Maciek, and All,


Mr. Tore - I have checked the Type VII C training manual and the word "Grease" is not there...  With the initial supplies was there some type of container of grease brought on-board?


Maciek - I made the changes suggested on pages 71, and 314, is this OK?


Mr. Tore - When ever you have the time (there is no real hurry for this because I have to do some yard work at home that I need to catch up on).


I hope I have my understanding of the Lubrication Oil problems resolved this time...


Page 72 - 73
Page 85
Page 97 - 99
Page 108 - 109
Page 125 - 126
Page 142 - 150
Page 176 - 177
Page 180
Page 429


I just uploaded the latest version of Skizzenbuch into my Dropbox folder...


Mark and Karel - I believe Skizzenbuch is very close to a finished product, and most likely there will be a correction version.  However, If you all see anything wrong, no matter how trivial, then please let me know. I would like Skizzenbuch to be accurate and easy to read and understand as possible.


Mr. Herrn Klaus Mattes will meet with Annemarie Bredow (Uboot-Museum) and with members of the German IMMH on April 22rd, and the day before that he attend a meeting and will present Skizzenbuch at the annual meeting of Uboat Wilhelm Bauer where he hopes to be re-elected to the board.


Skizzenbuch will most likely become a Website book and not a printed book because of the expense incurred with a printed edition.  However, my final version of Skizzenbuch will be encrypted with an embedded reader; it will not allow changes, but will permit printing the book...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2017, 01:40

Don.
The only reliable source we have for the old exhaustsystem of the U 570 execution, is plate 13 showing the coolingwater system. By comparing that with the U 570 images shown by Maciek I guess the KTB is refering to the inner exhaustvalve ( inside the pressurehull) which has its inner casing flange inside the pressurehull hence it is possible dismantle the valve disc into the compressor room. As shown on the plate a leaking outer exhaust valve shall fill the space before the inner valve, just as on the main engine system, hence a proper draining of that space as shown is nessecary. Contrary to the main engine system when we got the cylinders filled water, we turned the engines with open indicatorcocks, this is not possible with the Junker and as a last precausion a watersaparator was installed just before the compressor . A burned valvedisc as reported in the KTB might very well derive from a carbon deposit on the seating creating a local leaking jet acting as a burner on the seating. This is one of the reasons for grinding the deposits away as soon as possible. As I told before if you had such a difficult deposit on the seatings  we very often allowed the seapressure to act on the valve disc to increase the pressure against the seatings while grinding. This is one of the advantages to have the valves shutting with sea backpressure. On the image below I have tried to explain the system. I agree with Macieks theorie.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2017, 03:55
Hello Mr. Tore,


Did the old original Junkers exhaust system have the ability to grind the inner valve  and seat? 


http://uboatarchive.net/U-107/KTB107-6KTBMaschine.htm
War patrol from 21.4. to 11.7.1942 (6th War Patrol)


The KBT came from U-107 which was a Type IXB that was commissioned on 8.10.40. Would  U-107 have been upgraded with the new exhaust system?


U-107 was lost on 18.8.44 and no survivors...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2017, 04:27
Hello Mr. Tore,


I just thought about something that is very obviously different about the GW Diesel engine exhaust system design and the proposed Junkers exhaust system design:


The GW diesel engine exhaust design uses a beveled gear to swing a large valve shut with not a great deal of force. Therefore, the valve grinding and external seawater pressure is needed to force shut a fairly large diameter valve.


The Junkers compressor valve (proposed design) would be a fairly small diameter plate valve and it is being driven positively shut by the hand-wheel at the bottom of the internal exhaust casing. This type of valve shutting would not need the seawater force to help shut the valve...


What do you think?


Good night it's 6:27 AM...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2017, 05:31
Don.
I don`t know much about the developement story of the Junker exhaust system. As they had a fairly long history of troubles before they came to the last construction, I assume there are several alternatives fitted on the various boats. I don`t know, but I would be astonished if they skipped the grinding possibility of the innervalve.  I guess a grindig connection could be as proposed on my image below.
It was never a problem to shut the main engine exhaust dampers by operating the handwheels and no need for any external force. However when a carbon deposit was formed on the seating, external force (seapressure) helped the grinding pressure as a possible strong shutting force exerted by the valveshutting mechanism would increase the pressure resistance on the valvedisc pivot. As told before at some 3-4 meters the sea backpressure prevented the operating of the pneumaic grinding motors without a pivoting shutting force.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2017, 13:38
Don, Maciek.
I am moving to my summerfarm tomorrow morning, which mean I shall be without the net fo a few days reverting as soon as I can.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Apr , 2017, 23:37
Hello Mr. Tore, Maciek, and All,


I have been struggling with the Junkers Exhaust System...


The first issue was getting the gearing to match up with what is present locking segments in the upper pressure hull --- and the fix was to add another gear to my gear assembly and now I have a match when the internal exhaust grinding valve is shut and the segments on the upper hull. Nothing is out of time or sync!


The second issue was getting the segment to line-up with the external exhaust flap valve locking cam  on the upper pressure hull.


a) with a new grinding valve and seat - no problem
b) with a worn grinding valve and seat - big problem because everything moves too further.


I believe the resolution to that problem is to have a very heavy compression spring to close the grinding valve and allow the gear assembly to move to the point where the exhaust flap valve needs to lock the movement. I believe the use of the compression spring buffers the valve wear issue.


I searched the internet and there are die and clutch springs that are rated at 1200 - 1500 pounds. So these springs are good for a depth of 250 -300 meters and beyond...


I have attached the new images - what do you all think?


Kind regards,
Don_
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Apr , 2017, 03:07
Hello Mr. Tore and Maciek,


I placed the latest version of Skizzenbuch in my Dropbox folder...  Maciek, I corrected pages 431 and 438, thanks again....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Apr , 2017, 06:36

Hi Don,

I placed the latest version of Skizzenbuch in my Dropbox folder...  Maciek, I corrected pages 431 and 438, thanks again....


Page 431 looks good, but on page 438 you have mistakenly marked the valve for closing Schnorchel air intake duct as "Schnorchel Locking Pin Hand-wheel". I have marked (with green color) the position of this valve on the attached drawing. Without this valve, when the Schnorchel is lowered, while the boat is submerged, the diesel engine intake duct would be flooded.


BTW, on page 425, on the sketch of the 1st generation Schnorchel system, number 6 means "Schnorchel flooding valve", not "Schnorchel draining valve". This valve was needed to flood the part of air intake duct (between ventilation mast air intake and Schnorchel mast) prior to lowering the Schnorchel mast (to equalize pressure inside the duct with the outside sea water pressure).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 22 Apr , 2017, 09:49

Hi Don,

I have been struggling with the Junkers Exhaust System...

[...]

I have attached the new images - what do you all think?


If I understand correctly, in your design you assume that external exhaust flap (driven by lever) is interlocked with grinding plate?


Personally I think (as I tried to explain in this post (http://models.rokket.biz/index.php?topic=921.msg20476#msg20476)) that external exhaust flap is interlocked with internal exhaust valve. However I do not have any hard evidence to support this opinion.


Regarding the Skizzenbuch: page 97
Quote from: Sizzenbuch
In addition, I assume a second exhaust valve was introduced outside the pressure hull which has an air connection on the water side to blow the exhaust pipe between the valve and the muffler and operated from inside the pressure hull, with interlock to the aft buoyancy vent valve as previously discussed. As a final countermeasure a water-trap was fitted just before the Junker exhaust outlet as indicated on the system image Plan 13 for the GW engines (See partial plan below right).
In this fragment you are talking about interlocking the exhaust valve with aft buoyancy tank vent valve. I guess that part was not corrected during your latest updates.
Quote from: Sizzenbuch
However, for U-995, it looks like the external exhaust control lever next the Junkers compressor exhaust valve grinding mechanism works with the interlock which prevents shutting the grinding plate exhaust valve while the Junker compressor is operational and passing its exhaust gases to the water cooled muffler.
As I mentioned before, I have different opinion on this matter, however I cannot proof it.
One note: the design you propose prevents shutting the grinding plate while external exhaust flap is opened (which is not exactly equivalent to the Junkers compressor running).


And final note: we are still missing the proposal, how and where exhaust duct from Junkers compressor was connected to the housing of the valve.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Apr , 2017, 17:23
Hi Maciek,


How about this for a proposal of the entire system...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Apr , 2017, 01:22

Hi Don,

How about this for a proposal of the entire system...


Where the compressor exhaust duct penetrates the pressure hull?


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Apr , 2017, 01:54
Hello Maciek,


Where does the exhaust pipe penetrate the pressure hull...  Hmmmm! I thought that you or Mr. Tore would be the better person to answer that question.  I would think it would be somewhere near the back side of the Junkers compressor close to the water trap.  I sure hope it wasn't at the location of what is now the entrance door. The short answer is "I Don't Know"... 


I just uploaded a corrected version of Skizzenbuch into my Dropbox folder...


Page 98 - Internal Exhaust Valve = Internal Exhaust Grinding Plate Valve
                External Exhaust Valve = External Exhaust Flap Valve


Page 438 corrected, My fault I circled the wrong valve...  Now I identified both valves.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Apr , 2017, 02:13

Hi Don,

Where does the exhaust pipe penetrate the pressure hull...  Hmmmm! I thought that you or Mr. Tore would be the better person to answer that question.  I would think it would be somewhere near the back side of the Junkers compressor close to the water trap.  I sure hope it wasn't at the location of what is now the entrance door. The short answer is "I Don't Know"... 


It was a bit tricky question.  I'm pretty sure that exhaust duct was connected to the upper part of the inner valve casing (similarly as on attached photo from U 570 - marked with red dots).
There is no reason to make another opening in pressure hull (which of course also has to be protected with hull valve - most likely also water cooled).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Apr , 2017, 02:51
Hi Maciek,


The approach to the junkers exhaust exit looks to be much simpler in the Type IX C built 7.8.43,  They have a selector valve that dumps any water from the exhaust pipe to the bilge...  There is no water separator, and the internal exhaust goes to the internal exhaust valve casing, but nothing is shown at the exterion of the pressure hull...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 Apr , 2017, 04:15

Hi Don,

The approach to the junkers exhaust exit looks to be much simpler in the Type IX C built 7.8.43,  They have a selector valve that dumps any water from the exhaust pipe to the bilge...  There is no water separator, and the internal exhaust goes to the internal exhaust valve casing, but nothing is shown at the exterion of the pressure hull...


This diagram shows only that valve casing is water-cooled. The piping does not drain the exhaust valve. The f2 selector valve is primarily used for injecting anti-corrosion agent into compressor cooling system and secondarily for draining the cooling system.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Apr , 2017, 23:08
Hello Mr. Tore and Maciek,

The exhaust separator on U-995 looks a little more advanced than the one on U-570.  U-570's separator looks to be positioned higher, but it looks like U-995's separator had a pressurized drain system... I believe there are two drain pipes at the top of U-995's separator.


There may be a sight glass and a valve cut-off on the upper drains, or some type of a float valve inside the separator because they don't want exhaust fumes going to the bilge and then throughout the pressure hull...


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Apr , 2017, 23:33
After seeing this image from SUBSIM, It looks like the separators on U-570 and U-995 ate at the same height.


...and, Maciek notice there are two (2) tanks below the Junkers compressor.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Apr , 2017, 22:23
Hello Mr. Tore,


I hope all has gone well with you and your wife moving to your country home.  I myself would not have the will or stamina to take care of two homes and maintain the grounds.  Do you have someone to stay in either home while you are in the other one? I would think that your country home in the winter may have water pipes freezing unless the hearing is maintained at a decent level in the home. Although, being in a country home during the Spring and Summer is a welcome way to relax and enjoy life. However, my wife Maureen is from the over crowed city of Jakarta, Indonesia, 10 million people and growing and she does not like to live in the country. Before moving to Georgia, we lived just outside of Lexington, South Carolina, with a population of about 20,000 people; she called it the village! Now, we live about 30 miles north of Atlanta, Georgia, where the congestion is creeping north ever so slowly...


I have updated Skizzenbuch with the latest info from Maciek, and added a colored cover and trailer page like many hardbound books. Sometimes it's not expansive to go first class...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Apr , 2017, 01:28
Hi Don,

The exhaust separator on U-995 looks a little more advanced than the one on U-570.  U-570's separator looks to be positioned higher, but it looks like U-995's separator had a pressurized drain system... I believe there are two drain pipes at the top of U-995's separator.


There may be a sight glass and a valve cut-off on the upper drains, or some type of a float valve inside the separator because they don't want exhaust fumes going to the bilge and then throughout the pressure hull...

On the photos from U 570 you are considering water separator of the Junkers exhaust system, while on the photos from U 995 there is another separator: at the output of the air compressors.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 27 Apr , 2017, 01:40
...and, Maciek notice there are two (2) tanks below the Junkers compressor.

You are right Don, there are two flasks under Junkers compressor. Maybe these are flasks with starting air?

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Apr , 2017, 03:31
Hi Maciek,


Perhaps one (1) is the oxygen tank in the aft torpedo room that we could not find?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 May , 2017, 08:50

Hi Don, Maciek and all others.
I am finally back on the net after an eventful openening of my summerfarm. Putting an old  farm in the freezer for the winter require precautions and a lot of actions based on years experience.The trouble being an old man however is  your require some help to do the job and with helpful grandchildren, we thought we managed last year.Unforntunately not so, and we had a few frostbursted pipes, iceblockage of the water main supplypipe and quite a few other things as well, however now it seems everything is back to normal and we are on the net, touch wood! I see there are still a number of questions and I shall try attend as soon as possible. I guess the  starting air vessel for the Junker is as on my image below. The oxygenflask at the bottom stb boardside is found and as far as I know the Junker exhaustpipe and internal valve is removed due to the accessdoor made in the pressurehull of U 995. The further arrangement have to be guesswork and I shall revert with some proposals in a while.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 May , 2017, 14:15
Hello Mr. Tore,


Glad to see you're back online...  You answered a lot of my questions about the country farm home, and I guess all the preparations my men and mice can not foresee all the obstacles created by mother nature.  It's great to have help from your grandsons...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 May , 2017, 08:37
Don.
As far as I can see the Junker exhaustsystem has been of considerable consern and changes since it was introduced. The two stroke, opposed piston engine was susceptible to exhaustgas counter pressure and carbonisation due to the ballancing of the free pistons and I guess there are a number of executions as the developement occurred. Again we don`t have much drawings available thus we have to assume some of the solutions based on photografic images. Below is my proposal of the plain exhaustsystem were cooling piping and casing are omitted as well as the intricate interlocks and the grindingsystem. To prevent waterintrusion in the Junker through the scavenging ports which are open in the starting position is of course of paramount importance, hence the watertrap and drainage is placed at the lowest point just before the Junker. The starting procedure would be as follows: The opposed pistons are cranked in the outer starting position, the stern buoyancytank vent is shut, allowing the outer exhaustvalve to be opened, however prior to opening the valve, LP air is admitted to the space between the inner and outer shut exhaustvalves. When opening the outer exhaustvalve the airpressure is forcing the possible water into the silencer and overboard whereupon the inner exhaustvalve is opened, and possible residue water is drained at the waterseparator and the Junker can be started. I guess the extra exhaustvalve after the boardvalve on the old plan would not be nessecary with the assumed U 995 execution. Unfortunately both the boardvalve,drainage, watertrap and most of the exhaustpiping is removed on the U 995 presumeably to make visitors access through the door in the pressurehull .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 May , 2017, 22:56
Hello Mr. Tore,


Is the aft buoyancy tank venting hand-wheel located on the upper pressure hull (between the 6th and 7th frame port side) in back and above the e-compressor.  I don't see how the lever with the interlock segment connects to the aft buoyancy tank or the hand-wheel?


Maciek had provided an image that showed the aft buoyancy venting valve hand-wheel located between the 6th and 7th frame, and the hand-wheel for blowing the aft buoyancy tank with LP air located between the 7th and 8th frame.


I also noticed there is a step in back of the e-compressor for the crewman to reach these valve hand-wheels.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 May , 2017, 13:53
Don.
I have checked the pages in Your Skizzenbuch as requested and have following remarks.
Page 72.....Reason-to maintan the u boats correct buoyancy..... With such small amount of fueltransfer mentioned there is hardly any changes in the submarines buoyancy,or, the difference in weight between fuel and seawater is roughly 0.15 kg pr. kg water and if you only top up the day tank of say 175 kgs this means some 25-30 kgs weight difference. Apart from pressurerizing the internal fueltanks, one of the main advantages of the compensating water is to reduce the surface effect of a partly filled tank by keeping the tank full all the time.

Page 85..... normally it is the engineroom staff checking the compensatingwater when fuelling, not the depot personell.

Page 97-99  I Guess we should need a bit more Research on the Junker exhaustsystem as it is currently too many loose ends.

Page 108-109  I believe you have to vent the buoyancy tanks at any diving as otherwise shall introduce fairly large tanks with considerable variable buoyancy and free surface effect. I assume replacing the venthandle ( Wheel) from fore torpedoroom to the controlroom was a consequence of the alleys air superiority in 1943, increasing the need for crashdiving and a quick control of the bow down diving in the controlroom.
The Atlantic bow was introduced as you say in 1943 to improve the surface condition of the submarine by reducing the longitudenal pitching. I don`t think the wider beam bow is describing the Atlantic bow, rather a flare bow.

I guess the buoyancy tanks might influence the submerged condition if not vented. The air volume of the bow boyancy tank at 50 meter is compressed from appr. 8m3 at the surface to 1,33 m3. Which means theoretically a loss of 6,67 m3 displacement at the bow and 3,567 m3 at the stern. A total displacement loss of 10.237 which has to be compensated. Generally you want to avoid large displacement variations by having easy compressible gases (air) taking part in the descend. In this case of not venting the buoyancy tanks you would have to compensate for the loss of displacement by pumping out some 10.000 liters regulating waters whereas to compensate for the total pressurehull compression you need only 500 liters. Of course the temperature influence the calculation, but assuming the cooling effect of the lower temperatures at 50 meters would compensate for the compression temperatures. At 50 meters the compression of the airdisplacement in the bow and stern buoyancy tanks would upset the buoyancy and the trim of the submarine as well as introducing an undisireable surface effect.

Page 125-126. The aux coolingwater pump.... is located on the fore bulkhead port side... stb side.

Page 143 Using the other engines lubeoil pump is possible, but not the first choice. It is far easier and quicker to use the electrically driven aux. lubeoilpump by that you are able to use both systemtanks.

Page 144-145 As discussed earlier, the easiest way to transfer fuel from the submarines fueltanks is by submitting compensating water under pressure to the tanks. The aux.fuel tranfer pump is primarily used for draw fuel from another source (submarine?) to the fuel storage tanks.
Luboil hand pump. Normally the electric driven aux. pump was running before starting or turning the engines. The luboil handpump was as you say mainly used for maintenance jobs as well as for topping up the systemoil by fresh oil from the storagetanks.
Page 148. In the event of a failed luboilpump my first choice would be to use the electrically driven aux.lubeoil pump in stead of hooking up to the other engines luboil pump.
Page 429 Transfering fuel from inboard tanks to saddletanks. I am not familiar with not using the internal fueltanks and not cracking the while schnorcheling and not cracking the compensating water board valve. The reasoning that the engineroom gravety tank ( daytank) might be based on a misunderstanding as this tank is an open tank with 6 overflow pipes. May be you are refering to the interanal storagetanks?
The transfering of fuel from the inboard tanks to the saddletanks is a bit complicated to me as by pumping out fuel without watercompensating you introduce a fairly heavy surface effect in the large fueloil storage tanks during schnorcheling which you absolutely do not want. If you neverteheless should choose to pump fuel from th inboard fuel tank to the saddle tank you could just as well pump it to the gravety tank in the engine room.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 May , 2017, 22:23
Hello Mr. Tore,


Thank you for reviewing the many pages...


Page 72 - I was attempting to get across that compensating water always had to replace the fuel oil forced into the day tank.  Eventually, the internal tank would be half empty; in other words half fuel oil and half compensation water.  Possibly the U-Boat would not be able to dive if the internal tanks were half fuel oil and no compensating water.  Was my attempt too awkward?


Page 85 - I changed form "depot personnel" to "engine room personnel" in two places on that page...


Pages 97-99 - I agree...


Pages 108-109 - I changed the word "wide beam bow" to "flared bow"


Type VII C/41
surfaced displaces 759 tons
submerged displaces 865 tons
increased displacement when submerged 106 tons


This is the displacement (106 tons) from anything above the water line; pressure hull, tower/bridge, deck and casing, cannon, etc. I don't believe there is any weight gain by flooding the ballast tanks, just a loss in buoyancy because of venting the air volume in the ballast tanks.


Therefore, when the U-Boat dives and doesn't vent the buoyancy tanks, the air is compressed with depth to a greater extent and has little effect on buoyancy the deeper the U-Boat dives, but the water displacement gain in the buoyancy tanks does not need to be compensated for by pumping water from R1 or R2.


Where have I gone wrong again? I don't believe we need to counter the water weight in the flooded ballast tanks...


Pages 125 - 126 That was a dumb error, I had it correct on the drawing...


Page 143 - I added another line to the page with your sentence...


Page 148 - I think page 143 may be sufficient... What do you think?


Page 429 was taken from a U-Boat KBT from the uboararchive.net web site...

Note - the attached drawing seems to indicate there was the ability to hand pump the dirty oil tank contents overboard into the sea.  The current U-995 only has that short pipe with an end cap. That looks modified or wrong to me?

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 May , 2017, 08:01
Don.
The displaced water of a surfaced submarine is equal to the total weight of the submarine including equipment and crew. This displacement creates a positive buoyancy which makes the submarine float at required draft adjusted by the regulating tanks.
As a submerged submarine displaces the superstructure with pressurecontainers, ducts etc., above the surface waterline in addition to the surface weight deplacement, the submerged displacement of a submarine is larger than the surface displacement. This submerged displacement consist of components with variable compressabilities of which the gases (air) has the highest and steel the lowest. For a VIIC the pressurehull compression would be about 100liter per. 10 m, steel and other solid practical nil and possible air in tanks connected to the sea according to Boyle Mariottes Law: P1V1/T1=P2V2/T2.
As the submarines ballast tanks are vented, the displacement air is substituted by seawater and the displacement caused by the air is removed. The buoyancy created by this displacement is gone causing he submarine to have a passive descent if the regulating tanks are adjusted to a weight slightly larger than that of the deplacement loss.
During the descent the ambient waterpressure increases and a  compression of the compressable components start. As a consequence the submerged displacement decreases. This has to be compensated by discharging an equal amount of regulatingwater .
The pressurehull compression at 50m depth has to be compensated by 50 l.and a possible non vented bow buoyancytank of 8m3 would get an air compression to some 1.33m3 which means 6,67m3 less than the sealevel volume, thus the displacement of that tank would result in a buoyancy loss of 6,76m3 which has to be compensated to maintain the required buoyancy at a given depth. The easiest way to avoid such correction would be to vent the bow and stern buoyancytanks when diving and let the tank act as a freeflood area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 May , 2017, 20:03
Hello Mr. Tore,


Thank you for the info about displacement when diving the type VII U-Boat...


"possible non vented bow buoyancy tank of 8m3 would get an air compression to some 1.33m3 which means 6,67m3 less than the sea level volume, thus the displacement of that tank would result in a buoyancy loss of 6,76m3 which has to be compensated to maintain the required buoyancy at a given depth."


The bow and aft buoyancy tanks are above or at the waterline when the U-Boat is running on the surface... Therefore, the weight of these empty tanks (except for air) is compensated for at the U-Boat's waterline.  In a non-emergency dive the non-vented buoyancy tanks only present an air pocket which will slightly inhibit the U-Boat's diving rate, but as depth increases the air pocket is compresses and the overall diving resistance becomes nil at greater depths.


I don't see a buoyancy loss where any compensation is required in this scenario for the buoyancy tanks...


In an emergency dive the buoyancy tanks may be vented to eliminate the air pocket resisting the diving rate.


I apologize for my constant doubts, but I would like to fully understand this diving process.


Regards,
Don_


PS - This post of mine is numbered 666 - I guess the Devil is in the details... Ha ha!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 May , 2017, 23:44


Don.
I guess we  talk about Archimedes in this case and variable displacements and buoyancy: a body immersed in a fluid partly or wholly is boyed up by a force equal the weight of the fluid displaced by the body.  Just below the surface the volume of a not vented bow buoyancy tank displaces 8m3,  hence the submarine is buoyed up by a force equal to the weight of 8m3 seawater. As the air trapped in the tank is substantially compressed at 50 m depth to some 1.33 m3, the buoyancy force is still equal to the weight of the displaced seawater, however the displaced sea water, practically not compressible, is now decreased to 6.67m3 hence the buoyancyforce of the tank is 8-1,33= 6.67m3 less. The same happens to the pressurehull which is far less compressible than the trapped air in the buoyancy tanks. You can`t use Boyle Mariottes Law on the pressurehull, but an experience figure says the pressurehull is compressed by 100 l. per 10 meter diving depth corresponding to 500 l at 50m depth. As for the increased displacement due to the superstructure, the displacement changes are practically nil because it is not compressible as long as you don`t have airpocket trapped somewhere.
The basic for a submarines passive changing of diving depth  is changing the buoyancy force, diving by reducing the displacement (buoyancyforce) by venting the ballast tanks and surfacing by increasing the  displacement(buoyancy force) emptying the ballasttanks.  The buoyancy tanks are not listed as ballast tanks and do not participate in such diving procedure thus should be vented at the surface prior to diving and considered as a  freeflood area when submerged. to overcome the surface "resistance" you should use the Q tanks (Untertriebzelles).

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 May , 2017, 01:37
Being practically fully installed in my summerfarm, I have been able to pickup my painting hobby and brushed up my old painting of KNM Kaura ex U 995 on an immaginary crossing of the westfiord in Northern Norway around 1953. The old steamer in the background is the "expressship" S/s Finmarken southward bound wheraes the KNM Kaura is going north to the Barentz sea.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 May , 2017, 20:23
Hello Mr. Tore,



"Just below the surface the volume of a not vented bow buoyancy tank displaces 8m3,  hence the submarine is buoyed up by a force equal to the weight of 8m3 seawater."


Yes! I understand that statement...


"As the air trapped in the tank is substantially compressed at 50 m depth to some 1.33 m3, the buoyancy force is still equal to the weight of the displaced seawater, however the displaced sea water, practically not compressible, is now decreased to 6.67m3 hence the buoyancy force of the tank is 8-1,33= 6.67m3 less."


The 2nd sentence seems to emphasis the negative...
So the U-Boat at 50 m is buoyed up by the force equal to the weight of 1.33 m3 seawater (The effective buoyance displacement was reduced with depth). The 8m3 bow buoyancy tank was never part of the displacement balancing equation (Not Part of the Ballast System). When the U-Boat is on the surface; there is no positive buoyancy created by the bow buoyancy tank because it is above the waterline. Hence no compensation was required especially for air...


I think we both agree with that statement (Yes/No)?


The weight of the U-Boat prior to the dive is the same at 50 meters, or at 200 meters... However, the displacement (Volume) may be less because of hull compression and some water may be pumped from the regulation tanks to compensate and balance the U-Boat.


THE BOTTOM LINE____


I could see the U-Boat taking in 1,330 liters of water at a depth of 50 meters to compensate for the air contents in the bow buoyancy tank. However, if the U-Boat went down to 200 meters depth, the they would need to pump out about 1,000 liters of water to balance. That would not be desirable in an emergency situation and required to use the batteries to pump out the excess weight.


From our previous discussions, the buoyancy tanks were not considered as part of the ballast system. Mr. Tore - do you know if your Karua crewmen utilized the buoyancy tanks during a dive? I would think (Given with my lack of expertise) that the buoyancy tanks were only vented during an emergency dive situation...


What do you think?


************ Your Latest painting *******************


Excellent work, the airbrushing really makes thing pop out from the canvas.  My wife's (Maureen) father (Johannes) took painting lessons after he retired and did water color paintings before they moved to the US. He passed away about 3 years ago at the age of 89, her mom just turned 90 and is in good health. Did you take any painting lessons? Again Excellent work my friend!!!


Do you mind if I just use your latest painting in Skizzenbuch?


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 07 May , 2017, 21:58
Tore, the painting is great. Waves and sea are masterfully rendered. Congrats!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 May , 2017, 11:58

Don.
I guess a graphic could explain my ideas better that the poor wording, see below. I think we are in agreement with your first paragraph.

The weight of the submarine prior to the dive is the same at 50m or at 200m. I agree if you dont`t pump out any liquid or discard any objects from the submarine.
However the volume, displacement may be less because of hullcompression and some water may be pumped out of the regulating tanks to compensate. The water pumped out of the regulating tanks has no influence upon the volume/displacement but on the weight of the submarine, however if you blow out some water from the buoyancytanks it shall increase the submarines volume and thus the buoyancy of the submarine.
I could see the Uboat taking in 1.330 liters at a depth of 50 meters to compensate.
I assume you are referring to buoyancy tanks not vented. I guess you are missing a 0 here as at 50 m you have a total loss of buoyancy of 12,22m3- 1,33m3= 10,89m3  pluss the pressurehull compression 0,5m3 alltogether 11,39m3 water equal to 11.390 liters, a considerable amount of water to be pumped out against 50m.
At 200m the total regulating water which is required to be pumped out of the two regulating tanks would be some 15.200 liters to compensate for the aircompression in the buoyancy tanks if not vented. In case they are vented, nil. This is one of the main reason that the buoyancytanks should be vented prior to diving
The ballast tanks are normally not used for ballancing and trimcontrol. We use the regulatingtanks and the trimtanks as they are easier to control for such purposes. Again, a partly filled ballastank/ buoyancy tank create a fairly large free surface effect momentum. The regulating tanks are centrally placed and small length which minimize these unfavorable elements.
On the surface the buoyancy tanks have the vents shut, this is increasing the bow and stern buoyancy when the submarine is pitching, sometimes immersing the buoyancy tanks, hence together with the flared bow reducing the pitching which is the purpose for the tanks. At calm sea they have no function.


Re Graphic below.
If you don`t vent the buoyancy tanks submerged, the light blue area e.g. displacement becomes smaller as the seawater intrusion (dark blue) get larger( representing loss of buoyancy). A VIIC having a displacement variation between 6 and 11m3 not compensated would get trouble with the dynamic control of the submarine. Thus you have to compensate this decrease in buoyancy force by reducing the submarines weight, this is normally done by discharging regulatingwater by less extreme volumes..
On Kaura we kept normally the buoyancy tankvents shut at the surface and open as a routine in the divingpreparation.
In the event of a crash dive all the tankvents were opened including the Qs starting with the bow tanks.
 Both Q tanks corresponds to a buoyancy of 4m3. If the buoyancy tankvents were shut they would represent a buoyancy force of 12,22 -4= 8,22m3 displacement, a hopeless figure for crashdiving and destroying the normal exellent short divingtime of 30 seconds for a VIIC.
the buoyancy tanks were not only vented in emergency cases, but always when diving .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2017, 16:14
Hello Mr. Tore,


I searched through the entire "German Diving Regulation Manual," and not once are the Aft or Bow Buoyancy tanks discussed. However, they do cover the Negative Buoyancy Tank...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 May , 2017, 01:28

Don.
The Germans did not use the wording tank or buoyancy for these tanks, they simply called it for what is was, watertight bow and watertight stern. Wasserdichte  bug and heck.
In the hand book for the uboatcommander you shall find the watertight bow and stern mentioned as per my enclosure. The English translation is a bit wierd trying to make german words english, but anyhow I guess it would explain that the germans did as we, leaving the buoyancy tank vents open submerged.
By the way I forgot to answer you question on my recent painting, of course you are free to used it in your Skizzenbuch. Allthough I am as old as your father in law was, going on 89, I never took any painting lessons.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 May , 2017, 14:05
Hello Mr. Tore,


OK... So, If I understand the functionality of the bow ans stern buoyancy tanks, then the following statements are true.


1. Technically the bow and stern buoyancy tanks are not part of the ballast system because they are normally above the waterline and not affecting the U-Boat's overall displacement.


2. The bow buoyancy tank's primary function is to counter under cutting.


3. The stern buoyancy tank's primary functions are to assure the bow is in a down angle during a dive, and it's above the waterline for the Junker's air compressor operation.


4. Both the bow and stern buoyancy tanks are vented after a dive is initiated to eliminate the air pocket which will impact the decent rate slightly.


Comments?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2017, 01:13
Don.
Buoyancy tanks. In reply to your last post.
1. Yes, in bad weather surfaced having vents shut they increase the bow displacement when pitching, submerged vented, they are neutral as any non compressible material.
2. Yes, and reduce pitching movements.
3 No, the primary function of the aft buoyancy tank is to reduce pitching and increase displacement( buoyancy) , surfaced in bad weather, to counter act flooding of the Junker exhaust pipe.
The bow down angle assistance at passive diving is executed by main ballast tank 1 which is vented a bit later than the other main ballast tanks. The total bow down angle is achieved by speed and hydroplanes, dynamic, and the main ballast tanks ,passive. Both buoyancy tanks do not participate as they are vented prior to the diving order.
4. Normally both buoyancy tanks do not have any airpockets submerged as they are vented. The vents are shut after they are drained on the surface. If the weather  is bad you might speed up the surface drainage by shutting the vents and blow the tanks by LP air.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 May , 2017, 14:49
Hello Mr. Tore,
Hello Mr. Tore

I believe I read somewhere that the Junkers air compressor could be operational up to Sea State 5 - Wave height 2.5 to 4 meters, and swells moderate/long. I don't know if sea state 5 was the cut-off limit or was included in the operational zone?

Diesel Engine Starting

The second thing that became apparent to me was when you are starting either the GW or the MAN diesel engine with compressed air. According to the Diving Reg. Manual, the tail clutch should be dis-engaged and the clutch engaged between the diesel engine and the e-motor, so the e-motor can acts as a flywheel... Is this always the case when starting the diesel engine?

When running on starting air, at what rpm was fuel injected?
At what RPM do you engage the tail clutch to the prop?

How is the change over done when diving the U-Boat?

1. Do you shutdown the diesel, disengage the clutch between the diesel engine and the e-motor (both not running) and then start the e-motor to drive the prop?

OR -

2. Do you start the e-motor, then dis-engage the clutch (both running) to the diesel engine and then shutdown the diesel engine?

Conclusion - It looks like option #2 could be done in parallel with both diesel engines. While option #1 needs to be done serially because you don't want a sudden drop is speed.

When surfacing from a dive, what would be the diesel engine starting procedure?

3. Would you stop one e-motor, engage the Deisel/e-motor clutch and dis-engage the tail clutch to start the diesel engine, and then engage the tail clutch?

OR -

4. How???

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 May , 2017, 23:25
Don.
I don`t believe you can put up accurately a sea state where you could not operate the Junker, it all depends on different circumstances like the trim, how you place the submarine in relation to the waves, the speed and course of the submarine etc.
The main engines were started both with the mainclutch engaged or disengaged as well as  with propeller engaged and disengaged. Of course when you were charging the batteries alongside  at the quay, you disconnected the propeller clutch. Before they removed the reversing of the diesels, the engines were started and stopped many times during maneuvring ahead and astern with propeller engaged.
The injection of the fuel during start was a matter of the engineers feeling and experience. I should think some 30-50 revs. depending how much massforces were engaged on the propellershaft.
You engaged the clutches preferably at stop, otherwise at the lowest possible revs. Again, it was depending on the massforces connected on the shaft. The higher the speed and massforces, the more wear and tear on the double cone clutches. If you engaged the mainclutch even at moderate revs, the friction forces created smoke from the friction layors.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 May , 2017, 02:32
Hello Mr. Tore,


Thank you for the info...


One question


If during a dive and while on the surface, could you bring the diesel engines rpm down to 290, and at the same time fire up the e-motor to the maximum at 290 rpm, then could the main clutch be disengaged with out any friction or burning issues, or would there be a problem with mechanically disengaging a clutch while running (centrifugal force issues)? Perhaps the diesel engine would have a problem with suddenly no load? I guess that may kill that idea...


Just a thought...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 May , 2017, 03:15
Don.
Disengaging the engine clutch did not create a problem with regard to the heating of the friction lining of the double cone mainclutch, but a sudden loss of load could be hard on the governor of the dieselengine and would probably need an engineer at the fuelhandle. I Guess such crash diving action was taken when attacked by plane during diesel surfacecruising. The real problem with switching in and out rotating masses on the shafting is the torsional vibrations creating very large stresses in the shaftings which might break crankshaft as well as propellershaft. The primary part of the mainclutch ( attached to the dieselengine) act as a flywheel running disconnected at normal load, but when you switch in the e-motor/generators and  disengaging the propeller, you introduce a different torsional vibration scenario, which again is changed  switcing in the propeller shaft ( propeller) and for a GW engine connecting the Roots blower at high outputs.
In the earliy stage before you calculated the torsinal vibration stresses in the shafting quite a few broken propellershfts and crankshaft occurred. This resulted in a thorough calulation and an installation of a torsional vibration damper on the front of the crankshaft " chopping " up the worst vibrations.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 May , 2017, 23:47
Hello Mr. Tore,


Thank you for the last posting...


I have updated the following pages:


Prologue - pages XVI and XVIII - concerning the diving and surfacing sequence
Pages 108 - 109 - concerning the buoyancy tanks
Page - 414 - concerning an emergency/crash dive sequence


When you have time, would you please review and correct any problems?


At this point, I believe Skizzenbuch is in the final stage of being complete; unless, something comes up that is wrong and needs to be corrected. Everything I have added has been by making page lay-out changes and I haven't been adding any pages for several months because I don't want to have to re-index the entire book again. However, If something needs to be corrected, then I will do what ever is necessary.


I have uploaded the latest version of Skizzenbuch into my Dropbox account folder...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 May , 2017, 00:31
Don.
I have scanned your new skizzenbuch only and shall revert if any remarks. I think your Skizzenbuch is a never ending project as you go into more and more details, hopefully it would be more interesting for the reader. I am busy with the Junker exhaust and I have a few new inputs coming up in a few days I hope. I don`t like our present "solution" very much, so I assume your text has to be revised.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2017, 01:53
Hello Mr. Tore,


OK...  The only thing that must be considered with the Junkers internal exhaust valve mounted on the upper pressure hull is that it has to rotate the bottom external shaft segment and drive shaft extends to the upper segment which drives and intermediate segment (the interlock).  Also, it close/open the the grinding valve plate and position the intermediate segment so the lever may be enabled to lock or is disabled.  All of which must be accomplished by turning one hand-wheel...


That gearing ratio system was the only thing that I could come up with that would fit within the constraints of the outer casing.  Also, what does that 90 degree lever actually control when rotated or locked-out?


Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 May , 2017, 12:02
Hello Mr. Tore,


Is the Skizzenbuch 12-5-2017 PDF File that you uploaded to dropbox the file that you were going to modify?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 May , 2017, 00:21
Don.
I am sorry not being able to give you a quick answer on the Junker exhaustsystem, the reason being I am utterly confused as I can not remember the stern buoyancy venting system with interlocks  launched as a possible system for the venting of the stern buoyancy tank and exhaust valve of the Junker. I am afraid I have to switch to another assumption. In Bremerhaven is a  museum submarine of type XXI laying alonside afloat I have in fact seen it several times but not being onboard. This submarine was commissioned just at the end of the war and was never on war patrol. She was scuttled at the surrender but raised and recommissioned by the Bundesmarine in 1960 when Germany became a member of NATO and became the mother of the future modern submarines of the german navy as well as the Norwegian navy. Willem Bauer ex U 2540 was serving in the German Bundesnavy till 1980. Long story short, I stumbled over a photo of what looked exactly like our "Junker exhaustvalve and buoyancy ventingvalve" fitted aft in this XXI boat. To my astonishment the test stamping on the housing was in English and checking further I registered  this was an English design of a Bold ejector. My therory is that Nato has a standard type of decoy cannister used by Nato long after my time and the ejector was installed in U 995 after my time as a NATO standarization. Sorry I guess it is back to the drawingboard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2017, 02:13
Hello Mr. Tore,


I don't believe that device is not a Bold device... It is an exhaust valve for the Junkers compressor.  I believe you can clearly see the exhaust pipe in the upper right corner. I have a Type XXI schematic print that shows 2 junkers compressors located in the aft area of section 3 where the 2 - 6 cylinder diesel engines are located. I will post copies of the Type XXI schematics later. Also, I see dates stamped in the one area that look to be 11 8 43, and tested to 1000 lbs???  I believe the current Type XXI has only 1 junkers and 1 battery powered compressor.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 May , 2017, 11:13
Hi Gentlemen,


Tore, great spotting. I like your theory very much.


Don, according to US Navy Report on type XXI U-Boat (http://www.uboatarchive.net/Design/DesignStudiesTypeXXI.htm), this vessel was equipped with:
two Junkers compressors located in the aft part of the diesel engine room;
one electric compressor located in the pump room under the control room.


The "exhaust valve" visible on the photos provided by Tore is located in the aft room, on stb side:
https://www.flickr.com/photos/clemensv/9447842743/


I don't think that Germans led the exhaust duct from diesel engine room, through electric motor room, to the aft room.


I have attached photo of the original bold ejector installed in aft room (at stb side) of U 2518.
I think that post-war version of the ejector (as Tore suggested, of NATO standards) was installed in place of it.
It could be used as bold ejector as well as signaling flares ejector.


The question is, why Norwegians did not remove the Junkers compressor, when they decided to put the bold/flares ejector in place of the exhaust valve?


Generally, such post-war ejectors were called (at least in RN) Submerged Signal Ejectors.
Here you can find description of three types of ejectors: MK 2, MK 4 and MK 7:
https://maritime.org/doc/oberon/weapons/part2.htm
In my opinion, S.S.E. MK 4 is slightly similar to the arrangement found in aft room of U995 and U 2540.


At the bottom of the page, you will find some drawings of the "items" ejected from this device.


--
Regards
Maciek

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2017, 20:18
Hi Maciek,

Nice photo of the Type XXI's original "BOLD Device"...

OK.. I assumed wrong when I seen a photo of the e-compressor in the Type XXI. Now, I believe the current Wilhelm Bauer should have 3 air compressors; 2 Junkers and 1 electric. (see attached image 3372a)

I also don't believe the Germans ran the Junkers exhaust from the diesel room to the aft room because that makes no sense.

However, the photo c4834_o (attached) from the Wilhelm Bauer shows a Junkers exhaust valve in the aft section, in place of the original Bold ejector (your photo).  That looks to be dead wrong!


I believe that I understand everything you posted except the following:

"The question is, why Norwegians did not remove the Junkers compressor, when they decided to put the bold/flares ejector in place of the exhaust valve?"

At the beginning of your post you state that Tore's photo is of the exhaust valve (I think so).

1. The current bold ejector on U-995 above the Junkers compressor looks to be correct, and it matches up with the outer hull casing. Is this correct?

2. The current exhaust valve in the upper pressure hull looks to be original in U-995, but the junkers exhaust pipe was cut off. So we don't see the exhaust pipe to the water separator or the exhaust pipe from the separator Which should go to an exhaust hull valve (I think). Is this correct?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 May , 2017, 21:04
Type XXI Image


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 13 May , 2017, 23:54

Hi Don,

However, the photo c4834_o (attached) from the Wilhelm Bauer shows a Junkers exhaust valve in the aft section, in place of the original Bold ejector (your photo).  That looks to be dead wrong!


No, I think (the same as Tore) that it is not a exhaust valve. In my opinion this is post-war ejector of bold/flares, installed in place of the war-time bold ejector.

What would be the reason to install the exhaust valve in the aft compartment, with no exhaust duct (from Junkers compressors in Diesel engine room) connected?

I believe that I understand everything you posted except the following:

"The question is, why Norwegians did not remove the Junkers compressor, when they decided to put the bold/flares ejector in place of the exhaust valve?"

At the beginning of your post you state that Tore's photo is of the exhaust valve (I think so).


In my post I put the exhaust valve in quotation marks, to indicate that this item (supposed to be a exhaust valve before) should be explained in different way.
I'm sorry, if it was not clear enough.


1. The current bold ejector on U-995 above the Junkers compressor looks to be correct, and it matches up with the outer hull casing. Is this correct?

Right. The question if this is original, war-time ejector or was it altered after war too.

2. The current exhaust valve in the upper pressure hull looks to be original in U-995, but the junkers exhaust pipe was cut off. So we don't see the exhaust pipe to the water separator or the exhaust pipe from the separator Which should go to an exhaust hull valve (I think). Is this correct?


I state, that in U 955, in the upper pressure hull is post-war bold/signal ejector (submerged signal ejector). It was installed in place of the Junkers compressor exhaust valve. So the exhaust pipe from the compressor had to be removed (as well as water separator).
My question was, why they did not removed Junkers compressor also. Without exhaust valve, exhaust pipe and water separator, the compressor was useless.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 00:55
Hello Maciek,


Let's tackle this issue one item at a time...


First - the original German Bold ejector is mounter on the pressure hull above the Junkers compressor, and it aligns with the external slot in the external hull casing. There is a hinge on the Bold so that when the ejector is opened internally an new cartridge may be inserted.


In back of the junkers compressor is the water separator which is the exact same separator that you Identified in the U-570 photo.


See image


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2017, 01:10

Hi Don,

First - the original German Bold ejector is mounter on the pressure hull above the Junkers compressor, and it aligns with the external slot in the external hull casing. There is a hinge on the Bold so that when the ejector is opened internally an new cartridge may be inserted.

Right, however I'm not 100% if it is original German design, or was it altered by Norwegians after war (the design is quite different than ejector from U 2518).

In back of the junkers compressor is the water separator which is the exact same separator that you Identified in the U-570 photo.


No, the marked item is not the same separator as on U 570 photo. This is water separator of the hp air system, see the drawing.


You can trace the line going to Junkers compressor (the last fragment missing) as well the line going to the electric compressor). It is also possible to trace the connection to the hp line (with strainer attached).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 01:32
Hi Maciek,


We do have a water separator on the exhaust...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2017, 01:43
We do have a water separator on the exhaust...


Of course, but the exhaust separator is NOT present on U 995. The connections of the separator on U 995 clearly show that this is water separator on output of the air compressors.


In other words, there should be two different water separators originally, but now, only one is present.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 01:52
Hi Maciek,


Don't these photos look the same?


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2017, 01:59
Don't these photos look the same?
In my opinion, the exhaust separator on U 570 photo is closer to the boat's centerline, while the HP air separator on U 570 is just at the hull.
I think that there is some space visible between the hull and exhaust separator on U 570.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 02:05
Does this photo help with the space issue?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2017, 02:14
Does this photo help with the space issue?


Yes, this photo presents a little different angle view.
However, as I said before, the line connections suggest clearly that is HP compressed air separator.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 02:21
Hi Maciek,


The only thing that bothers me is that the Wilhelm Bauer Type XXI has that device in place of the original Bold. It does not in any way look like the SSE Mark 2 or the SSE Mark 4.


The device in U-995 does not look to have the ability to swing open like the Mark 2, nor does it have the ability to hinge open like the Mark 4 because of the pipe and the segment shaft to the interlock.


Mr. Tore cold resolve the question about the junkers compressor...
*********************************************************************
Mr. Tore - do you remember if the Junkers air compressor was ever used on U-995?
*********************************************************************


If the Junkers compressor was used by the Norwegians, then changes were made during the Museum renovation; But what changes?


See the 3 images for a comparison...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 14 May , 2017, 08:44

Hi Don,

The only thing that bothers me is that the Wilhelm Bauer Type XXI has that device in place of the original Bold. It does not in any way look like the SSE Mark 2 or the SSE Mark 4.


In my opinion, in case of Wilhelm Bauer the matter is clear: the war-time bold ejector was replaced with post-war SSE. Where could they put the new ejector? In the place of the old one.


I didn't say that it looks like SSE MK 2 or MK 4, I said it looks slightly similar to the MK 4.


At first, in my opinion, the ejector on Wilhelm Bauer is the same type (or maybe not of the same type but the same design) as ejector installed in place of the Junkers exhaust valve on U 995.
Here is the comparison:


(http://i66.tinypic.com/e8ahkn.png)


1. shaft (for opening the external flap)
2. gear for driving interlock (to prevent opening the internal flap when external flap is opened and vice-versa)
3. shaft for driving interlock
4. blanked connection
5. line connection for flooding/draining the ejector
6. the hinge
7. the shaft for opening internal flap




I'm not sure if you agree that these are the same devices or not?

The device in U-995 does not look to have the ability to swing open like the Mark 2, nor does it have the ability to hinge open like the Mark 4 because of the pipe and the segment shaft to the interlock.

OK, this is how it supposed to work (according to me, at least):
The shaft (1) driven by hand-lever is for opening the external flap. The flap is opening against the sea pressure.
The flap is interlocked (by means of the gear 2 and shaft 3) with internal flap, to prevent opening both flaps at the same time (similarly as in case of the torpedo tubes).
To open the external flap (with charge loaded into the ejector), the pressure inside the ejector has to be equalized with external sea pressure. Otherwise, the sea pressure forces the external flap (opening outwards) to be closed. The equalization is done by means of the line (5), which makes possible to flood the ejector with external sea water (similarly as in case of torpedo tubes).
When charge was ejected, the external flap is closed and the ejector can be drained by the same line (5).
The piping on U 995 is missing, however on Wilhelm Bauer the piping seems to be complete: there is visible line branching to small hull valve and the branch to drain/vent the ejector.

And the most important thing: how the internal flap was opened (to load anything into ejector)?


I think that internal flap (or breech) was opened similar to the S.S.E. MK 2, the breech was moved/slid aside horizontal (unlike the MK 4, where the breech is opening downward).


(http://i66.tinypic.com/2mriooi.png)


The hand-wheel can drive some kind of dog-catches (as in case of the normal hatches).

Mr. Tore cold resolve the question about the junkers compressor...
*********************************************************************
Mr. Tore - do you remember if the Junkers air compressor was ever used on U-995?
*********************************************************************


If the Junkers compressor was used by the Norwegians, then changes were made during the Museum renovation; But what changes?


The brief history of KMN Kaura:
01.12.1952 - commissioning in Royal Norwegian Navy
1957 - overhauling and modernization
12.1962 - putting into reserve


Removing of the Junkers exhaust could be done by Norwegians in 1957. They could use it before 1957 and could abandon using it after 1957. During the renovation/restoration to the state from May 1945 (in 1971) there would be no sense to install new ejector in place of the Junkers compressor exhaust valve.


In the book U 995 by Eckard Wetzel, on page 144 there is a small photo of the aft torpedo room, taken on 1965, when U 995 was moved to Kiel, before any restoration work. I think that on the photo the present arrangement is visible. I mean that the device in place of Junkers exhaust valve (I assume that it is S.S.E) was present there in 1965.
It supports the assumption that it was installed there during overhaul in 1957.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 17:33
Hi Maciek,


I am wrong...  It looks like you and Mr. Tore are correct!  When one has so much time invested in a theory, then it's hard to let go.


Please go to this web site and review the posts because it looks like the bold device in U-995 and Wilhelm Bauer is from a Klass 205 U-Boat.


http://www.forum-marinearchiv.de/smf/index.php?topic=13257.15


See the photos...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 May , 2017, 19:44
Hello Mr. Tore and Maciek,


The Bold in U-995 and the Wilhelm Bauer Type XXI may be a Dutch or German design because the original Bold cartridges were very short "like a can of beans" but the newer Bold devices ran a distance and did a burst of bubbles or an explosion (Bang). so they were most likely longer.


They replaced the original bold in the Type XXI (after the war), I don't understand why they didn't replace the Bold in U-995 (unless the older cartridges wouldn't fit or launch in the newer Bold, so they kept both).


FYI (Maciek) - according to documentation I read; they replaced the 2 junkers compressors with e-compressors post war on the Wilhelm Bauer.


Rergards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 May , 2017, 00:37
Don and Maciek.
Sorry on my place in the world remote in the Norwegian forrests I lost my internet connection for some 24 hours. I am back and can answer the easiest question first, we used the Junker in my time, but it was very nosiy and needed frequent overhauls like cleaning of carbon deposites from the diesel pistons to prevent unballance. We definitely preferred the E-compressor. After I left the Kaura she had a major overhaul and I guess they the installed quite a few gadgets like the balkongeraet, a few US electronic devices which I assume was related to submarine traffic detection/registration etc. I have only seen these devices by photos and can not comment further on that. It could very well be they removed the Junker. My point is, I fully support Macieks theory, after my time a lot has been changed on ex.U 995 since my time onboard was terminated in 1954.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 15 May , 2017, 14:11

Hi Don,

I am wrong...  It looks like you and Mr. Tore are correct!  When one has so much time invested in a theory, then it's hard to let go.

Please go to this web site and review the posts because it looks like the bold device in U-995 and Wilhelm Bauer is from a Klass 205 U-Boat.

http://www.forum-marinearchiv.de/smf/index.php?topic=13257.15 (http://www.forum-marinearchiv.de/smf/index.php?topic=13257.15)

See the photos...


Nice photos. Indeed, they were taken in the Klasse 205mod U-Boat. However, this ejector is a different type than the ejectors from Wilhelm Bauer and U 995. Generally, the shaft for opening the external flap is very close to the ejector tube (on Wilhelm Bauer and U 995 it is a little more distant from the tube, to accommodate the interlock gearing).
The interlock is realized in a different way: the handle of the shaft for opening the external flap is removable. It can be placed at the shaft (to open the flap) only when the breech doors are in close position.


By the way, I must correct myself:

1. shaft (for opening the external flap)
2. gear for driving interlock (to prevent opening the internal flap when external flap is opened and vice-versa)
3. shaft for driving interlock
4. blanked connection
5. line connection for flooding/draining the ejector
6. the hinge
7. the shaft for opening internal flap


Of course it should be:
2. gear interlock
3. shaft (driven by breech doors) for interlock


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 May , 2017, 19:31
Hello Mr. Tore and Maciek,


It looks like the aft torpedo room in U-995 is presently in a modified state where the Junkers compressor was not usable because of the removal of the junkers exhaust system. If the junkers compressor were usable, then the setup would be similar to the one as seen in U-570.


They installed a different version of the bold launcher in U-995. Do we know if there was an issue with the newer bold decoys and the older bold launcher. I don't believe there is an issue of horizontal launch Vs vertical because the Wilhelm Bauer does a horizontal launch.


I will search the internet to see if I can find a layout for the junkers compressor in a type VII...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 May , 2017, 18:25
Hi Maciek,


Can you copy the photo form the U 995 book.. Or do you have another of the same era?
On the Bold device, I see how it gets flooded and drained, but how does the internal canister get launched?
On the Old Bold Launcher it looks like a piston on a guide/limit shaft was used and driven by compressed air?

Regards,
Don_.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 May , 2017, 01:04
Hello Mr. Tore,


I believe that U-995 (Kaura) a Type VII C/41 had the same aft torpedo room Junkers exhaust configuration as U-570 a Type VII C. Then in 1957 the modernization disabled the Junkers compressor and they installed the second Bold Ejector.


I understand the functionality of the original side launch ejector with the piston and the attached long rod to create the end point for ejection.  This is the same design as the torpedo launch piston groves which only allow the piston to travel so far down the tube.


I don't quite fully understand the functionality of the vertical launch ejector because it does not have the original launchers piston with a capture rod which also prevented the launchers gases from escaping to the surface and giving up the U-Boat's location.


Since this device was installed in 1957 (Peacetime), could it be that they just use compressed air to launch a distress signal and they really don't care about the launch gases reaching the surface?


At this point, I really don't think it matters because the 1957 renovation and modernization was never part of the original German wartime U-Boat Type VII C, or the Type VII C/41!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 May , 2017, 00:28
Hello Mr. Tore, Maciek, and All,


I have updated Skizzenbuch and placed the latest version into my Dropbox folder...  I decided only to cover fully the Original German WWII version of the BOLD ejector, and not the version that was installed into U-995 (Kaura) in 1957. Besides, the air and drain lines have been cut-off so we can't see where they went and to what they are connected to, so it would only be guessing on our part. I don't want guesses in Skizzenbuch, only the facts and correct information...


Kind Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 23 May , 2017, 00:54
Hi Don,


regarding the post-war ejector: I think we should use term 'signal ejector' (as in the Oberon type sub manual) instead of 'bold ejector'. The signal ejector was used to indicate the position of submarine by means of flare (at parachute) or smoke. So ejecting the cartidge by means of compressed air was the simplest way, and the air bubbles appearing on surface were not a problem.


I think that in those times submariners did realize that Bold (being a active sonar counter-measure) was obsolete, because cold war was dominated by passive hydrophone arrays.


The Bold type counter-measures were later developed into torpedo decoys.


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 May , 2017, 02:19
Hi Maciek,


I agree...  It looks like they took the bold ejector like the one that was installed into the Wilhelm Bauer Type XXI and modified it for the use as an emergency signal ejector, and they don't bother to capture the launching compressed air.


Regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2017, 02:56

Don
I guess Maciek got it right.  During my submarine training ( early 1953) the device was only briefly mentioned and named SSE (submarine signal ejector) and as far as I remember not installed in RN submarines before the new O class which in my time was on the drawing board and very hush,hush. We only learned about a "bubble decoy" which as far as I remember was like a small torpedo containing magnesia pellets generating air bubbles in contact with sea water. I guess it was launched like a torpedo. The pillenwerfer launched up to 4-5 cannisters of 10 cm diameter simultaneously resembling pills in a row hence, pillenwerfer. In my time (peacetime) we used the ejector for Veris flares to indicate torpedo firing during exercises and was handled by the torpedopeople. I think in the beginning (my time) the ejection was done by air not bothering by the bubbles. Today the SSE is developed to a complex device by the Nato navies which are totally different from the pillenwerfer. I don`t think the todays SSE has anything to do in a Skizzenbuch for the VIIC.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 May , 2017, 16:53
Hello Mr. Tore, Maciek, and All,


I updated Skizzenbuch with the info about our final discussions concerning the "Ejector" for emergency signals in U-995's aft torpedo room upper hull.


MY latest version of Skizzenbuch is in my Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 23 May , 2017, 23:20
Hi Don,
excuse me for the request: can you post the link to your Dropbox folder ? Is it available to anyone ? ( I never used Dropbox, and so I'm not very versed on it...).
Thanks in advance.
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 May , 2017, 03:12
Hello Filippo,


"Skizzenbuch: U-Boat Type VII C Project" has not been finalized yet and I rely on Mr. Tore and Maciej to proof read the book and provide corrections and suggestions. However, I can state that it is very close to finalization...


Skizzenbuch: U-Boat Type VII C Project - 503 pages in an 11 x 17 inch format with an Appendix of 7 large pull-out document/schematic sheets


I had a contract with Schiffer Publishing to print the book, but they backed out in January of this year. If I end up with no publisher, or no internet sponsor, then I will purchase software to copy protect the Skizzenbuch PDF file from any unauthorized changes, and also an LLC to protect me. At that point, I may provide a copy protected file with an embedded reader to many of the U-Boat websites for distribution, including this one.


Maciej Florek has translated many U-Boat related manuals and documents for years, and we all have had the great fortune to see and download his excellent work.


Also, Dougie Martindale has provided U-Boat docmentation on the interned for years for us to enjoy, and I understand that Dougie is working on a book that he would like to see published. I believe his chances are excellent because of his knowledge on the subject, and it would be in a publisher's standard book size format.


Kind Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 May , 2017, 03:19
Hi Maciej,


I must apologize... Ever since you translated my U-Boat Type VII C manual for the uboatarchive.net, I have been typing your first name as Maciek like it was written above the manual credits. I have been wrong all these years and you didn't correct me?


I guess my first name would be Dumb and not Don?


I will need to make this correction is Skizzenbuch...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 24 May , 2017, 04:03
Thanks Don,
I did'nt knew anything of what you told, and I heard now the ( right ) intention of publishing all thing in a book.
Obviously, I'm really interested to buy that book, or the PDF files if it will not possible to print a book.
I'm looking forward to see any news about that...
Thanks.
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 24 May , 2017, 08:32
Hi Don,


your first name is absolutely Don.


My first name officially is Maciej (used in documents and so on). However, the other form (maybe not diminutive, because it is not shorter) is Maciek, used by family and friends (because all you guys from this forum I consider as friends).


--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 May , 2017, 13:28
Hi Maciek (My Friend),


I will not change the spelling of your first name in Skizzenbuck, unless you would prefer the Official Document spelling. It's not a big deal to make that change, I just a search and replace in 5 of the word documents and then join the 9 PDF files to create the Skizzenbuck 11 x 17 - M + I.PDF file.


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 May , 2017, 19:49
Hello Mr. Tore and All,


Maciek provided me with a photo of U-995 taken in 1965.  There is no Junkers air compressor in the aft torpedo room, and the emergency signal ejector is installed in the upper pressure hull...  Therefore, when the Germans restored U-995, they installed a Junkers air compressor, but I don't believe there is an exhaust or HP air connection.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2017, 02:46
Don.
I guess this confirms our assumption. Somehow after 1955 the Junker was removed. In 1953- 1954 for sure the Junker was in place although not very frequently in use. As far as I remember we had to clean the dieselpistons every 75 hours due to carbonization causing unballance vibrations, no wonder they removed it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SnakeDoc on 01 Jun , 2017, 08:33
Hi Don,

maybe you will find this photo interesting. It presents loading torpedo to the aft torpedo tube of U 564.
The Junkers compressor, as well as part of exhaust duct and two exhaust valves are visible.

--
Regards
Maciek
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2017, 09:19
Hi Maciek.
Interesting photos it looks as if they used the pressurehull opening for the Junker outer  exhaustvalve for the SSE.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jun , 2017, 15:43
Hi Mr. Tore and Maciek,


I added the images to Skizzenbuch page 98 and the latest in in Dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jun , 2017, 23:59
Don.
I am afraid I have lost the general view of the pages I should check as it has been so many changes, is it possible for you to give a survey over which pages in your Skizzenbuch you want me to check?
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2017, 01:21
Hello Mr Tore,


I believe we are current on pages to be verified...  Your post number seems to be stuck at 2,249??? and mine is stuck at 697???  I have just updated page 98, 99, 464, 465, and 466 and I am going to update Dropbox in about 10 minutes.


I do have one question...


Which spelling is correct?


Reinhard "Teddi" Suhren


- OR -


Reinhard "Teddy" Suhren


I see both spellings for Teddi - Teddy on the internet?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jun , 2017, 01:28
Hello Mr. Tore,


The latest version of Skizzenbuch is now uploaded into my Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 04 Jun , 2017, 04:34
Hi Don,


the correct spelling is "Teddy".


I have read his autobiography "Nasses Eichenlaub", according to his own memories he was nicknamed "Teddy" because of the flabby kind he walks.


Regards
Falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jun , 2017, 15:44
Hello Mr. Tore,


There is a Index.pdf file in the Dropbox folder... Is this some corrections?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jun , 2017, 00:10
Don.
Sorry Don, I guess it was accidential put there by me in my effort to get to get a picture of which pages I need to check. Just a proof of that I am really not belonging to the IT generation. I am gradually starting to read the complete Skizzenbuch and I am afraid it shall take some time before I am through the book in this rural remote area of the world. I shall keep sending my comments as I read the book, but right now I got a message that my connection is reduced to 64 bits / sec.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jul , 2017, 19:02
Hello Mr. Tore, Maciek, and All,


I uploaded the latest version of Skizzenbuch into my Dropbox folder yesterday.  I corrected a spelling error in a graphic on page 390 "DESIGN"...  The word spell checker would not find that error in a graphic JPG!  I also changed any reference to myself as the author and replaced it with Managing Editor.


Two reasons:
1. You all provided the information in Skizzenbuch and I just rearranged the words and graphics to follow a readable format. You all contributed to my education and knowledge about the Type VII U-Boat and I am eternally grateful.
2. It may take me awhile before I distribute Skizzenbuch to all at no cost as an educational resource... I must establish an LLC for "Krystall Klare Publishing" and then Copyright "Skizzenbuch as a Multiple Source Book" and finally purchase "CopySafe Software" to protect Skizzenbuch from any unauthorized changes or modifications to the released form.


This will cost me a little over $500 USD; It's amazing that you must follow this procedure just to give away a book/document. I believe I may be able to get all this done later this year, or sometime early next year.


Therefore, we all still have time to make changes to Skizzenbuch until I get it copyrighted...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2017, 02:57

Don.
This answered my latest question which mean I can proofread your final Skizzenbuch. I shall start reading but I am afraid it shall take some time depending how many rainy days we get during the summerholydays of my children and grandchildren. I particulary liked you changed name on your publishing company and shall revert if I have some comments to your Skizzenbuch. Sorry you encountered so much trouble for you enthusiastic work.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Jul , 2017, 19:35
Hello Mr. Tore,


I had to correct page 356 because the top photo and paragraph was wrong! This still had the old info about the signaling device being the Junkers exhaust valve and lever.


I uploaded a corrected version of Skizzenbuch in the Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Jul , 2017, 16:51
… "Krystall Klare Publishing“ …


Do you mean kristallklar? Or is that a kind of play of words?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jul , 2017, 22:00
Hi Mark,


I didn't mean it to be a play on words... 
What should it be correct for Kxxxxxxx (German) Publishing (English)?


Krystall Klare
Kristall Klare
Kristallkar


I ran all 3 through my German Translator and they all come out the same; Crystal Clear???  I wanted Crystal Clear (to be in German) + Publishing..


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 23 Jul , 2017, 00:13
Kristallklar Publishing would be perfect. (It would be a good name too)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 23 Jul , 2017, 12:25
Hi guys, when it's expected the publishing of your book ? I'm looking forward to buy it....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Jul , 2017, 13:51
Hello All,


[The Bad News]
I had a committed publisher who cancelled about a month before the printing date.  Their reason for the cancellation was that they perceived the book was too expensive to print in a possible 11 x 17 format (about 500 pages) and the readership audience is too small and specialized to meet their required profit margin. Also, there are over 700 images (photos and drawings) which are mostly in color.


[The Good News]
Late this year, or early next year, I will get an LLC for "Kristallklar Publishing" and have the book Copyrighted, and purchase CopySafe software to encrypt "Skizzenbuch: U-Boat Type VII C Project" and the "Appendix Image Folder"... Once this is done, then the book may be downloaded as a viewable and printable file.


[The Best News]
I have spent the last 3 years learning about the Type VII C U-Boat from my great collaborators/friends on this web site. This is justifiably their book; I'm just the editor who assembled the information! We now have some time to review Skizzenbuch and assure to our best efforts that all the contents are 100% accurate.


Once all my milestones are met, then I will make the downloadable book file "Skizzenbuch: U-Boat Type VII C Project" available. I still have to work things out as far as distribution on several Websites, and I don't believe there will be any cost to the reader...  Free!!!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Jul , 2017, 14:12
Hello Mr. Tore, Maciek, Simon, and Mark,


I corrected the publishing name to "Kristallklar Publishing, LLC USA" and that was the only change I made to the latest uploaded version of Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 24 Jul , 2017, 00:43
Hi Don,
excellent news....
I would like to have a classic paper book, but a free download printable file is maybe better, mostly in this economic crisis with few money circulating.....
Let us informed about the date of extimated availability of the file.
Respect to you and to all the book's authors....
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jul , 2017, 00:41
Hello Mr. Tore and All,

Dougie Martindale has provide me with some historical Info where I had incorrect info for several U-Boat photos.

I made corrections to the following pages:

127, 151, 170, 181, 210, 378, 440, and 446.

Also, Dougie has graciously said he would create replacement maps for pages 436 and 437. I may have a legal issue using Google Maps.

I still have an open issue on page 210 - The pitot tubes were underneath the bow torpedo tubes up through the U-Boat Type VII B. They were moved form underneath the bow torpedo tubes on the U-Boat Type VII C and beyond. The only issue I have is; where were the pitot tube/tubes located on the Type VII C U-Boat? Obviously, they must be below the waterline, and I can visualize - If a U-Boat Type VII B is sitting on the bottom, then the pitot tubes could get damaged, or plugged with debris (thus a good reason for the relocation).

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jul , 2017, 02:10
Hello Mr. Tore and All,

I just uploaded the latest version of Skizzenbuch into my Dropbox folder...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jul , 2017, 23:49
Hi Filippo,


Dougie Martindale has written the following:
http://amp.rokket.biz/docs/u-boat_colours_with_photos_5.pdf

U552 netcutters were removed between March and April 1941. For an accurate info to modellers about Type VII modifcations: [amp.rokket.biz (http://amp.rokket.biz/reference.shtml)] scroll down to "U-BOATS: Type VII Modifications" an awesome work by Dougie Martindale


Plus,
http://u-552.blogspot.com/2008/07/outside-of-ct.html (http://u-552.blogspot.com/2008/07/outside-of-ct.html)


I hope this helps...  Skizzenbuck doesn't get into the details about specific U-Boats. I attempt to explain how everything works internally and externally.


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Aug , 2017, 20:08
Hello Mr. Tore and All,


It is my sad duty to inform you all that I have received an email this morning from Maciek Florek's wife, Olga Florek, that he had recently passed away. I will truly miss my very dear friend. However, a friendship is forever, so I look forward to seeing Maciek later!


Kind regards,
Don_




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 05 Aug , 2017, 20:12
I’m really shocked. He was such a great Uboat enthusiast with awesome projects. He was one of those I hoped to work with in the future.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 05 Aug , 2017, 23:12
Hi Don, if the file is available in your Dropbox folder, how can I have access to it ? Or it is still in preparation and not available for download ?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 06 Aug , 2017, 01:29
Hi all, I realized now the content of the message about Maciek: I didn't know him, but I'm so sad for the lost of an U-Boat enthusiast.....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Aug , 2017, 07:28
Hello Mr. Tore and All,


It is my sad duty to inform you all that I have received an email this morning from Maciek Florek's wife, Olga Florek, that he had recently passed away. I will truly miss my very dear friend. However, a friendship is forever, so I look forward to seeing Maciek later!


Kind regards,
Don_





Very sorry to learn the bad news, Maciek was a man of great VIIC knowledges, yet very modest in promoting his theories. It was a pleasure getting to know him and exchanging ideas as well as theories on the VIICs. Maciek, on my last post to you:  R.I.P.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 06 Aug , 2017, 15:00
Hello everyone,

Thank you, Don, for informing us of this dreadful news. Maciek was always very helpful and kind and I have been particularly appreciative of his help in my U 47 book. Without doubt he was a highly respected expert in his field. As a talented researcher, he was kind enough to share his comprehensive knowledge with us. He will be very sadly missed by us all.

If anyone is not aware, Maciek is the author of the Torpedo Vorhaltrechner Project, which can be viewed here -

http://www.tvre.org/en/home-page

He also wrote the following page -

http://www.ubootwaffe.pl/en/u-boats/equipment/torpedo-tubes-of-german-u-boats

Best regards to all,

Dougie

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Aug , 2017, 17:02
Hello Mr. Tore and All,


I have uploaded my latest version of Skizzenbuch into my Dropbox folder... I only changed page II and made a few spelling corrections.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 07 Aug , 2017, 01:51
Hi Don,
excuse me for my insistence, but I don't understand if you uploaded the file Skizzenbuck on your Dropbox folder just for the insiders, or if it's vailable for all interested on U-Boats....
Consider that I have not any experience of Dropbox....
Thanks in advance for answer.
Cheers.
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Aug , 2017, 10:22
Hello Filippo,


I (The Managing Editor) had four (4) contributors to Skizzenbuch; Mr. Tore (The Main Expert), Maciek (Now Deceased Expert), Simon (Art Work), and Mark (Help with German Text Translation). Anytime I make a change to Skizzenbuch, I notify my contributors so they may review the content in my Dropbox folder and suggest any needed corrections or changes. This is the process that we have followed for over three (3) years while I have written/managed Skizzenbuch.


Skizzenbuch is not a released book as of yet... Currently, I sent a book proposal to the Naval Institute Press, but I am not naive about the prospects. So I have two (2) alternative plans as well; publish the book on my own or distribute the book as a encrypted PDF free over the internet. The most expensive option for me is the free PDF file over the internet because of the cost of the encryption software. I will not allow Skizzenbuch to be changed without my control of the content!


So, this is where I stand on the distribution of Skizzenbuch to date! I believe that "Skizzenbuck: U-Boat Type VII C Project" is about finished and very few changes will occur after today. I am in a situation where I am waiting on a Publisher's decision, or if that fails; I must come up with the cash needed for one of my other two (2) options.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Aug , 2017, 21:28
Hello Mr. Tore,


I have a question for my own personal knowledge about resupplying fuel and lub oil to the U-Boat.
1. I assume they can use the resupplying port's pumping pressure, or use the U-Boats Aux lub oil pump to fill the lub oil tanks.
2. Do they press lub oil through the diesel engines, or do they fill the lub oil tanks by pressing clean lub oil through the diesel engine's normal supply lines?


Last question...  My U-570 Plate 9  (fuel oil) and Plate 14 (lub Oil) show the filling lines on the port side. However, the attached photos and Simon's drawings show the U-Boat accepting the resupply on the starboard side.  Are the plates wrong?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Aug , 2017, 01:21

Don.
I am right now up in the mountain for a couple of days under slight pressure of my wife to  attend som Plays, thus limited access to my papers.
However the lube oil of the VIIC GW engines without lubeoil centrifuges are based on a so called dry sump principle which means each mainengine has generally its own separate system with system tank. Normally you don`t fill up the systemtanks directly by shore supply, you top up or fill the lubeoil storage tanks I or II (port &stb) and take a possible luboil supply to the system tanks from the storagetanks.  In case of need you can indeed use the aux luboil/fueltransferpump to distribute the oil internally.
You never take fresh luboil from ashore directly through the engines, always to the storage tanks through the course filters.
As to the lubeoil filling pipe, I  guess the external hose filling cap is slightly to the starboard almost on the top of the presurehull. The downpipe inside the pressurehull follows the starboard side of the fore enginroom bulkhead door and the coursefilter ( nuts and bolts) underneath the floorplate starboard side having a crossover to the valvestchest on the port side. So use Simons drawings as far as I remember they are correct. I`ll revert as soon as I can find my images.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 08 Aug , 2017, 05:21
I just read about Maciek, and am shocked and deeply sad. The Forum has lost a precious source of information, a most fine researcher, one of its cornerstones in fact. He seemed to know every single part of a Uboat, and he was always available to provide information, even the apparently unanswerable information, for the ones in need. A major blow to the Uboat enthusiasts worldwide and to my morale. But, as Don said, we'll catch up with him sooner or later and will have the most pleasant technical conversations about uboats in those vast oceans up there somewhere, i have still a lot of unanswered questions to ask.
Farewell Maciek, you will be greatly missed!




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Aug , 2017, 08:29

Don.
I guess it would probably be easier to have a look at plate 14 and 9 simultaneously as plate 14 only indicate inlet and outlet of the fuelling and lubeoil supply. I have tried to combine the two on my image below. You`ll see that both  hose connections for fuelling inlet and lube oil supply are situated almost at the top of the pressurehull eg nearly at the center. Contrary to my memory the downpipe and strainer for the lubeoil supply is on the port side of the engine room front door whereas the fuelling pipe is on the starboard side going under the floorplates to the strainer before crossover to the distribution valvebox.
Hopefully the image is selfexplanatory.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Aug , 2017, 20:41
Hello Mr. Tore and All,

Thank you for the quick response about re-supplying the lube oil and the fuel oil to a U-Boat Type VII C.

I have made changes to the following pages: 123, 151, 171, 178, and 243 (replaced a photo). I changed these pages with new 3D images from Simon who has done outstanding work! The latest version of Skizzenbuch has been uploaded to Dropbox...

Mr. Tore - Your wife has been with you for over 50 years, and she deserves your full attention! Keep focused on the most important relationship in your life, and the rest will fall into place...

Kind regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Aug , 2017, 00:53
Don, we are just on the way to the high mountain theater raining and temperatures hoovering around 8 centigrade, open air theater for 6 hours and 3 hours driving. Indeed my wife deserves the effort, we actually married in 1953 when I still was the chief of U 995 KNM Kaura and got a week off for marrying. Reverting in a small week.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 15 Aug , 2017, 04:42
Hello all. Just came back from my vacation and learned this terrible news :(   

I sitting here shocked, i had a few conversation bits with him and he was clearly a fantastic person. I have spent countless of hours on his websites and reading his input on this forum.
A really valuable, friendly and open community member.

R.I.P Maciek.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: David83 on 16 Aug , 2017, 13:13
Rip Maciek      :'( :'( :'( :'( :'(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Aug , 2017, 23:07
Hello Mr. Tore,


I have been reviewing the bow hydroplane clutch and drive mechanism; How does this drawing look to you?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Aug , 2017, 03:11
Don
Exellent images. I guess it shows the arrangement of the old VIICs The latest executions did not have the atwartship shaft going right to the hydroplanguard and the shaft ended in a nut fixing halfway on the plane having an accesshatch right on the top where the nut was situated. As far as I remember the void space of the plane was filled with some sort of epoxy or recine. There was no contact between the hydroplane and the guard.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Aug , 2017, 22:50
Hello Mr. Tore,


Here is my 2nd attempt at the drawing...  What do you think? Also I found a photo that shows a hydroplane removed...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Aug , 2017, 00:56
Don.
Again excellent images, the hydroplanes are fixed by a nut, not bolt. I remember once being submerged the fwd. hydroplane operator had trouble operating his hydroplane which according to him did not respond and the hydroplane seemed to be locked in a down position. When I crawled in to the narrow space i discovered that the mechanical connection from the motordrive to the transmitter for the resistive network was broken and the electric indicator in the controlroom showed full up whereas the plane was full down. Otherwise your images shows one of the drawbacks of mechanical operations, the numerous greasing points required.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Aug , 2017, 16:41
Hello Mr. Tore and all,


I updated pages 194 - 198 and uploaded Skizzenbuch 11 x 17 - M + I.PDF into my Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Aug , 2017, 19:53
Hello Mr. Tore,


After doing a little more research...  It looks like David Westdood's book "Anatomy Of The Ship - The Type VII U-Boat" the forward and aft hydroplane drive motors are a hydraulic type motor.  I could see this type of motor because the hydroplane arm comes up against a metal stopper. Therefore, I would assume that the dual rudder motor is also an hydraulic motor as well...


However, there is nothing in the German Plans 1 thru 34 to indicate electric or hydraulic motors driving/controlling the hydroplanes or the dual rudders.


I checked the electrical plans for the Type VII and Plan 10 shows electric motors.


Could David Westwood's book be wrong?


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Aug , 2017, 22:30
Hello Mr. Tore,


I think definitely electric motors...  I was wondering if they had stall motors when the planes reached their limit - I found out there were 'Limit Switches" for all three planes and rudders.  I have attached the translated drawing...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Aug , 2017, 00:26
Don.
Hydraulic operation of the hydroplanes ,and rudders, were the most common systems for submarines in my time, and I remember coming back from my submarine education in UK and onboard a VIIc, the most stricking exstensive differerence was the use of electric driven hydroplanes and rudders. You are right in your assumption both hydroplanes and rudders were electrically operated on the VIICs.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Sep , 2017, 12:30
Hello Mr. Tore,


When will you be leaving your country home and heading back to the city? From your description, it looks like the fall and winter months at the country home location will get very cold and tons of snow...


Here in sunny Georgia, my summer project in 90 degrees plus weather was to re-do my back yard hillside. The builder placed burlap covering on the hillside which rotted away within 2 years and allowed the weeds to grow around the plants. So, I stapled down a heavy fiber covering to prevent erosion and to stop the weeds from growing. I built a 150 foot stone retaining wall, and had a contractor to place Railroad Ties on the upper part of the hillside, and red mulch covering the hillside area.


This project took about 2 months and I told my wife Maureen that my "Honey Does" were all used up for this year...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Sep , 2017, 12:32
MY last photo...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Sep , 2017, 13:38
Don.
Amazing garden, way out the wilderness where we are living. We are just in the final stage of harvesting, primarily, mushrooms and berries before shutting up the farm for the winter. The last item is very complex as i have to drain about a mile waterpipe, washing machine and dishwasher, internal waterpipes etc etc. Plus filling up the waterlocks with antifreeze and blow all the pipes by compressed air before eveything goes into winter freezer. Hope to be able to return to the civilization and proper broadband by end this month. In the meantime the moose hunting has started in our forest and it is safer to stay at the farm enjoying the autumn colours.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Sep , 2017, 16:39
Hello Mr. Tore,


Can you tell me what these markings on the hull casing and on the saddle tanks are representing?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 18 Sep , 2017, 17:45
The roman numbers fit to the number of the MBTs at this position.
The marking V is where MBT 5 is and III is where MBT 3 is located at.


(but of course I have no idea what it really is  :) )

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2017, 01:08
Hello Mr. Tore,


Simon and I have been discussing the Kingston valves in the saddle tanks.  I have a very good photo of U-99 and the Kingstons look to be almost square. However, the Kingstons look quite different on U-995???


Did the Germans need to rebuild the saddle tanks during the restoration?  See the images below:


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2017, 01:11
Hi Mark,


You know, sometimes I believe my brain goes out on one of those senior tours.  It looks like you are correct.. Those would have been added when they restored U-995 for the museum.


Thanks,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Sep , 2017, 01:44
Hi Don and Mark.
As mention many times before, the museum U 995 do not show the real U 995 and I can not remember the markings in question. I checked with the limited documentation I currently have access to and I guess the markings are related to the alteration to the hull, making the museums version. The markings were not on the hull at the arrival Kiel from Norway, the first time I noticed the markings was when the hull was placed on its concrete bed at Laboe and having access doors for the visitors. As to the Kingstons for MBT3 they are indeed rectangular, but welded shut for security reasons, as the fore free flood gates in the casing. It is possible to crawl into MBT 3 through the Kingstons, I have done it myself, and to climb on the casing side using the free flood gates as step holes ( which I have not done). My image below shows the story.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Sep , 2017, 03:38
Hello Mr. Tore and All,


I found the location of a plate for access to the MBT 3 air shaft.  This was pointed out (fold-out schematic in the back of the book) in the U-Boat Archive Series Volume 7 – REPORT ON U-570 – H.M.S. GRAPH…

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Sep , 2017, 00:04
Hello Mr. Tore,


I have been reviewing Skizzenbuch and I made what I believe is a correction to the lower right drawing on page 350.  I had the "Emergency Shut-Off Valves" swinging outward. I believe the valve truss structure was designed for the valves to swing inward. Do you agree?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Sep , 2017, 01:40
Hi Don.
I am in my car for a two days trip. My first impression is that your correction is OK. Reverting tomorrow. Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Sep , 2017, 23:43
Hello Mr. Tore,


Do you know if the MBT 3 Emergency Shut-Off valve heads are round or rectangular like the Kingstons valves for the Saddle Tanks? The uhistoria.com drawing sort of looks like they may be rectangular, but I'm not sure after talking with Simon...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Sep , 2017, 05:32
Don. I guess the emergency shut off vents for the MBT3 ventingducts are swinging inwards for open position. Further I would guess the venting valvediscs  are circular.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Sep , 2017, 23:13
Hello Mr. Tore,


I have been updating the uhistoria.com drawing by labeling all the frames.  I noticed that FBT 2 and FBT 4 do not extend to the full end of the taper.


FBT 2 starts at a taper and extends to frame A24 and then the tank extends to D34
FBT 4 starts at D46 and then the tank extends to D62 and then the tapered area continues for a few frames
See my attached drawing...


It looks like the tapered ends are not part of the Fuel/Water Ballast system. I have a photo of what looks to be a late Type VII C, or Type VII C/41 where there seems to be 3 vent holes in the tapered area of FBT 2 at the bottom side of the tank. I have not see this on other Type VII U-Boats; was this modification documented anywhere?


See my attached photo...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Sep , 2017, 12:14
Don. You are rigth the fairings of the MBT2 and 4are not a part of the sadletanks volume. They are only plates for streamlining the ends of the tanks. I cannot explain the floodgates on your image but having checked my files of VIICs and VIIC/41s there are no such floodgates. On the museum VIIC they have made a few slots at the bottom of the tanks with a dripnose, this was never on the original U 995 or KNM Kaura.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Sep , 2017, 16:01
Hello Mr. Tore and All,


I corrected all the FBT 2 and FBT 4 drawings in Skizzenbuch to reflect the forward and aft fairings which are not part of the fuel/ballast tanks. The latest version of Skizzenbuch is in my Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Sep , 2017, 16:37
Hello Mr. Tore,


I uploaded the latest version of "Skizzenbuch 11 x 17 - M + I.pdf" to my Dropbox account and I uploaded a new "Image File" folder with all the images 001 - 768, each image has the page number referenced.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 27 Sep , 2017, 20:27
Is page 46 new? I can’t remember seeing it before.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Sep , 2017, 02:04
Hi Mark,


No page 46 is not new... Strange that you should ask?


I just made a correction to page 46 while doing a review...


The RED needle is pointing to the second gradicule on the RED scale on the differential manometer pressure gauge. This means the Q Tank has a positive differential pressure of 2 atü above the outboard pressure. The U-Boat Diving Regulations Manual No. 381 requires action to be taken because there is a possibility of a ruptured Q Tank if not vented immediately. Q Tank was designed with knee structures to resist external compression forces, but not internal expansion forces.


I changed the word from blowing to vented...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 28 Sep , 2017, 05:32
Just imagine if they had this wrong in the original manual  ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Sep , 2017, 14:35
Hi Mark,


No, that was just my dumb error...  There was no manual showing the Differential Manometer, so I improvised. A few years ago, I confused the words blowing and venting! that's why I'm going back and reviewing Skizzenbuch again. I made lots of errors in the beginning...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Oct , 2017, 13:04
Hello Mr. Tore,


Page 109 had the following sentence...


"Hence, the Junkers internal and external exhaust casing in the aft torpedo room has a shut and well seated grinding valve plate and a shut external flap valve located in the external Junkers exhaust casing which provides a double water barrier and preventing a water intrusion into the Junkers exhaust and cylinder chamber."


There is no grinding valve plate, so I changed it to...


"Hence, the Junkers internal and external exhaust casing in the aft torpedo room has a water trap located between the external/internal exhaust valves and the compressor’s air intake to impede sea water intrusion into the Junkers exhaust and cylinder chamber.


Does this change meet with your approval?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2017, 00:17
Hello Mr. Tore and All,


I have uploaded the latest version of Skizzenbuch to my Dropbox folder.  I have corrected the Prologue (20 pages) and the first 175 pages thus far. It may take me a few weeks or so to complete my review.  If anyone sees a problem anywhere in Skizzenbuch, then please let me know and I will make the necessary corrections.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Oct , 2017, 21:43
Hello Mr. Tore,


I was wondering if you had any photos or drawings showing the gate valves on the common air venting trunk for FBT 2 and FBT 4? Was there enough room below the wooden deck and the fairly small metal deck door to have an attached hand wheel to open/shut the gate valves. or was the hand wheel just removed?


See attached photo...


I can see where there would be space for  the FBT 2 residual gate valve hand wheels could be present...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Oct , 2017, 23:34
Hello Mr. Tore,


I was wondering if you had any photos or drawings showing the gate valves on the common air venting trunk for FBT 2 and FBT 4? Was there enough room below the wooden deck and the fairly small metal deck door to have an attached hand wheel to open/shut the gate valves. or was the hand wheel just removed?


See attached photo...


I can see where there would be space for  the FBT 2 residual gate valve hand wheels could be present...


Regards,
Don_

Hi Don

The gate valves for FBT 2 and FBT 4, never had a hand wheel, this was an old mistake on my 2D drawing that Tore and I noted.

Also the hatches you have arrow are not the hatch cover for gate valves. The hatches you are talking about are the next ones forwards.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Oct , 2017, 23:41
Hello Mr. Tore,


I was wondering if you had any photos or drawings showing the gate valves on the common air venting trunk for FBT 2 and FBT 4? Was there enough room below the wooden deck and the fairly small metal deck door to have an attached hand wheel to open/shut the gate valves. or was the hand wheel just removed?


See attached photo...


I can see where there would be space for  the FBT 2 residual gate valve hand wheels could be present...


Regards,
Don_

Below you are see the two hatches for the gate valves.
(https://farm5.staticflickr.com/4486/37447016250_b2a6913eec_o.png)
This images has been resized. Click to view original image.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Oct , 2017, 23:48
(https://farm3.staticflickr.com/2083/32031607244_b12417c70b_o.png)

(https://farm1.staticflickr.com/503/32059952603_b0941cfa16_o.png)

You can see above that a handle slotted into the hex reset on top of the cover. The hatch cover is angled because there is not room under the decking for the gate valve.

Do sure what the handle look like, sorry  :'(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 14 Oct , 2017, 23:51
(https://upload.wikimedia.org/wikipedia/commons/8/8b/U-826_after_surrender_at_Loch_Eriboll_Scotland_1945_IWM_A_28532.jpg)
Here are the real hatches on U-826  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Oct , 2017, 01:42
Hi Simon and Mr. Tore,


U-826 was commissioned on 11 May 1944 and probably one of the last Type VII C's  built.  It looks like the RFO /Water Ballast gate valves can be open/shut without opening any metal doors on the deck.


How about the earlier Type VII C's...  I have attached a plan for U-552 which was commissioned on 4 December 1940.  I have marked where I believe the gate valves are accessed for FBT 2, and I have also marked what I believe to be the access doors for the FBT 4 gate valves.


See attached drawing,
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 15 Oct , 2017, 02:31
Don, as seen in http://models.rokket.biz/index.php?topic=921.msg20817#msg20817 (http://models.rokket.biz/index.php?topic=921.msg20817#msg20817) if they are the hatches for FBT 2 gate valves they would have the worng frame number.

I will try to post pictures of FBT 4 hatches tomorrow.

As for the earlier Type VIIC's, if you look hard enough you will see them on most boats. The only thing I have noted is that on the some late war Type VIIC/41 they sometime used a wooden hatch.

Early Type VII's with hatch.
(https://farm5.staticflickr.com/4486/37449071060_51f1f9c0f5_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2017, 02:09
Hello Mr. Tore and Simon,


I now know the FBT 2 and FBT 4 gate valves never had hand-wheels because there is no space below the wooden deck.  I think it was possible for the FBT 2 residual gate valves to have hand-wheels, but most likely they were removed to keep the change-over process as uncomplicated as possible.


I have attached one of Simon's drawings and a photo where it looks like there is a hole in the wooden deck to provide access to the gate valve towards the center of the deck.  What do you all think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2017, 02:41

Hello Mr. Tore,




Are you and the wife back from your farm and in the big city yet?  Here in hot southern Atlanta Georgia; If the weather forecast even suggest that there will be a snow dusting, then all the schools are closed. People make a mad rush to all the grocery stores and buy all the milk and bread they can find. I guess the fear of starvation makes people do crazy things.  I'm originally from northern West Virginia where I had to walk to school in 2 - 3 feet of snow, they never closed the schools because of the winter weather.  I assume it's the same way in Norway; you just tough it out!...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2017, 08:49
Hi Don. Yes we are back in the civilisation, only to discover we forgot a couple of important items which shall be picked up by our grandson this week. Although we have had our first frosty nights, no snow as yet don`t miss it in my age. It take a few days to get back to the daily life in the city, but we are almost there.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Oct , 2017, 15:50
Don, the small hole in the deck is a access hole for a locking handle for this hatch (see below). I not sure how the locking system works, you either lift or push down on the handle.

(https://farm5.staticflickr.com/4507/37033037974_fc8a938652_o.png)
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2017, 19:17
Hi Simon,


Great info...  I have attached a photo that shows the FBT 4 and FBT 2 vent holes in the saddle tanks.


I have marked with red dots on your drawing where I believe the FBT 2 residual gate valves are located under the wooden deck hatches. Do you think this is correct? Also, is there room to have hand-wheels attached to these gate valves under the deck, or were the hand-wheels always removed for this set as well? That photo I had of a crewman getting out in bad weather with a hand wrench (Claw) tool makes me believe the hand-wheel was once a possibility...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 16 Oct , 2017, 19:44
Hi Simon,


Great info...  I have attached a photo that shows the FBT 4 and FBT 2 vent holes in the saddle tanks.


I have marked with red dots on your drawing where I believe the FBT 2 residual gate valves are located under the wooden deck hatches. Do you think this is correct? Also, is there room to have hand-wheels attached to these gate valves under the deck, or were the hand-wheels always removed for this set as well? That photo I had of a crewman getting out in bad weather with a hand wrench (Claw) tool makes me believe the hand-wheel was once a possibility...


Regards,
Don_

Hi Don,

I have not research the FBT 2 residual gate valves http://www.uboatarchive.net/U-570/U-570Plate16.htm (http://www.uboatarchive.net/U-570/U-570Plate16.htm) valves b1 or d1 so I not sure. Since I am working on the saddle tanks I was soon start working on the piping that are found around them.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Oct , 2017, 02:38
On many of the valves not frequently used we removed the handwheels to prevent accidental operation. As to the gatevalves in the venting systems for MBT/fuelreservetanks 2 and 4, the gatevalves were only operated when changing the systems from ballast and fuel configuration and vice versa. I guess the standard would be to remove the wheels. A wheel wrench is a tool very often used by the crew for many type of valves. If you study the "sliced" XIC in US you`ll find many gatevalves in the casing, most of them tilted to accommodate the high valvecasing,  a drawback of the gate valves. The images are from a IXC but I guess the same valves are used for the VIIC as well. You may see quite a few of the valves have no wheels fitted and are even operated by bevel gears and rods, I guess however on a VIIC they were mostly locally operated..
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Oct , 2017, 17:50
Hello Mr. Tore,


From what I can see on the Type VII U-Boats, the hand-wheels were not installed on the gate valves for FBT2 and FBT 4 on the venting duct; there was no room for the hand-wheels because of the deck space above was practically nil.  However, there looks to possibly be space to install the hand-wheels on the FBT 2 residual gate valves. The photo of the crewman going out in bad weather with a claw tool in his hand may support that theory. We'll just wait and see if Simon's new drawing of the hand-wheels for the gate valves on the FBT 2 residual cross-over pipe has the space above and below the deck...


I uploaded my latest version of Skizzenbuch to my Dropbox folder which has major changes to pages 86 and 88 (lower half)...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Oct , 2017, 11:23
Hi Don

I was looking at page 86 and the FBT4's gates valves are cover with different hatches compare to FBT2's. I will try to post pictures today after work.

Simon
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Oct , 2017, 13:55
Hi Simon,


No rush...  I'm only at page 237 on my review of Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Oct , 2017, 01:12
Hi Don

I was looking at page 86 and the FBT4's gates valves are cover with different hatches compare to FBT2's. I will try to post pictures today after work.

Simon

(https://farm5.staticflickr.com/4456/37096971424_5f62d20993_o.png)
Fig. 1. Port FBT4's gates valve hatch.
This images has been resized. Click to view original image.



(https://farm5.staticflickr.com/4454/23953921478_187629f1e8_o.png)
Fig. 2. Starborad FBT4's gates valve hatch.
This images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2017, 03:06
Hi Simon and Mr Tore,


Great images... I believe I may need to do some major changes to this Skizzenbuch section with all the latest drawings. It looks like the gate valves in this set of drawings has access for the change-over through the wooden deck doors. Again, I don't believe there is room for a hand-wheel to be installed on these gate valves...


(37096971424_5f62d20993_o) - this drawing sort of compares to the attached photo of U-201. If you look at the RED circled area there is a hole in the deck.  During the change-over to the water ballast configuration the FBT 2 and FBT 4 gate valves must be opened (access through the wooded deck doors)?


What does this mean for the drawing for U - 1308 and the metal plates with holes to change the gate valve configuration?


However, the header tank water pressure to FBT 2 and FBT 4 must also be cut-off.  Could the round holes in the deck be the access point to change-over the header tank water pressure selector valves? I remember the photos of the Type IX/C U-534 had the selector valves under the deck with what looked like there was plenty of room to install a hand-wheel, but there was none to be seen...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Oct , 2017, 01:05
(37096971424_5f62d20993_o) - this drawing sort of compares to the attached photo of U-201. If you look at the RED circled area there is a hole in the deck.  During the change-over to the water ballast configuration the FBT 2 and FBT 4 gate valves must be opened (access through the wooded deck doors)?

What does this mean for the drawing for U - 1308 and the metal plates with holes to change the gate valve configuration?

Hi Don

The different between U-1308 and the war-time photo of the hatches for the FBT4's gates valve is easily explained… the Schnorchel.
 
When they added the Schnorchel piping they had to change the hatches around the front of the CT casting.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Oct , 2017, 15:28
Hi Simon,


Agreed, but not a great deal of difference of the hatches around the tower center and aft section... The U-Boat with the Atlantic bow added 280 mm forward.


Note - the drawings may have a slight error as to the exact locations of the hatches...



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 23 Oct , 2017, 14:35
Hi Don & Tore

Any idea of the pipe dimension of the Fuel oil venting piping (http://www.uboatarchive.net/U-570/U-570Plate8.htm (http://www.uboatarchive.net/U-570/U-570Plate8.htm)) for MB & RFO Tanks 2 & 4?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2017, 02:23
Main Diesel Engine Exhaust System Group

Hi Don & Tore

While researching the Fuel oil compensating system, I noted that my original right-angle gearing which was based on the internal right-angle gearing was incorrect, below are the correct style of right angle gearing. It looks like the big different is how it was fixed, it not a pipe flange but a large hex screw.

(https://farm5.staticflickr.com/4459/37848565116_1f5cbcb0c3_o.png)
(https://farm5.staticflickr.com/4443/37896598911_66cc0a1eaf_o.png)
Fig. 1. Original right-angle gearing.

(https://farm5.staticflickr.com/4461/37866228312_e0af196485_o.png)
(https://farm5.staticflickr.com/4471/37848564566_9386817f43_o.png)
Fig. 2. New right-angle gearing.

These images has been resized. Click to view original image.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2017, 02:27

Hello Mr. Tore,


I have been reviewing pages 61 through page 63... See the attachment.


The lines above and external are used to test for when the RFO saddle tanks and internal tanks are full...


The hull section on the right shows the sampling of the internal bunker/tank 2 going to a bucket to measure the remaining fuel oil.  What I believe they are doing with the 3 other lines is testing for water when the tanks are empty; FBT 4 port and Stb and IB 2 (1 bucket with 4 lines).


The hull center section in the center shows the same setup for the internal fuel oil bunker/tank 1 for measuring the contents. They have another line going to a single bucket where they are testing for water when the IB 1 tank is empty (1 bucket 2 lines).


The hull center section - the lines at the top of R 1 port and stb go to a bucket, but I'm not sure why... They could open the lines going to the bucket to allow R 1 to vent while refueling, and monitor the long glass sight tube to know when to stop the pumping.


a) What is this bucket for and where is it located?
b) If the valves were shut going to the bucket, and the depot pumping continued for a few seconds. What kind of problem could result?

The meaning of Transfer, Delivery, and Venting...
c) The line in R 1 is pressurized when transferring fuel oil to another tank
d) The line in R 1 is pressurized when delivering fuel oil to the gravity/day tank to fuel the diesel engines.
e) The line in R 1 is venting when the tank is being refueled by a pumping station.

Are these the correct definitions for Transfer, Delivery, and Venting in this instance?


The hull section on left looks OK...  They can test the FRO 2 saddle tanks for water at the top when the tanks are empty.

One additional question... Were the collection funnels for fuel oil over-flow physically below the deck, or was there only the vent lines with shut-off valves? So the fuel oil depot station personnel carried the funnels on-board to drain the fuel oil over-board?

I really apologize for changing this post so many times - I'm finding out things as I go...
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2017, 02:42
Hi Simon,


What is different from this?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Oct , 2017, 21:39
Hello Mr. Tore,


I solved one issue that was confusing me...  "Austritt Triebölmeßgefäß" = Outlet drive oil measuring vessel or "fuel oil measuring vessel", this is NOT an "Air Gauge" that I had labeled on Plan 8 and Plan 8a!!! I could not figure how to get it to work and measure fuel oil pressure...

I found "Austr Triebölmeßgefäß" in the Type IX plans and we had "Austr Meßgefäß" in the type VII C plans for the same device...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2017, 21:42
Hello Mr. Tore,


I solved one issue that was confusing me...  "Austritt Triebölmeßgefäß" = Outlet drive oil measuring vessel or "fuel oil measuring vessel", this is NOT an "Air Gauge" that I had labeled on Plan 8 and Plan 8a!!! I could not figure how to get it to work and measure fuel oil pressure...


I found "Austr Triebölmeßgefäß" in the Type IX plans and we had "Austr Meßgefäß" in the type VII C plans for the same device...

Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 24 Oct , 2017, 21:47
Hi Simon,


What is different from this?


Regards,
Don_

This is a old drawing and there has been a few big updates of the Diesel Engine Exhaust system.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Oct , 2017, 21:16
Hello Mr. Tore,


I am still working on the  Plans 8 and 8a dealing with fuel oil testing and measurements.  I have ran across some inconsistencies between these plans.


Plan 8 shows a horizontal view of the fuel oil tanks with the various pipe connections and collection buckets, and we see 2 pipes going to the aft collection bucket and 4 pipes going to the forward collection bucket in the control room.  This drawing seems to agree with the many photos that I have on file.


Plan 8a shows a frontal slice view of the fuel oil tanks with the various pipe connections and the collection buckets, and we see 4 pipes going to the aft collection buckets and 4 pipes going to the forward collection bucket in the control room.


Obviously, Plan 8 and Plan 8a don't agree, so something looks to be very wrong! Plan 8a shows two pipes from the top of the R 1 regulating tanks port and starboard and then to a collection bucket. However, plan 7 shows the very same 2 air pipes from R 1 going to a muffler.


Therefore, I believe Plan 8a should be noted as being incorrect, or I could graphically make correction to the drawing... I have attached the 3 plan drawings... What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Oct , 2017, 22:22
Hello Mr. Tore,


What do you think of this change?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2017, 20:49
Hello Mr. Tore,


I changed the attached photo because I had the vent valve labeled incorrectly as the MBT 3 Vent...  It's too high to be MBT 3's vent valve. I also have a question about the pipes for exhaust blowing MBT 3. Do the piped from the exhaust blowing manifold enter the upper pressure hull area and then extend down to MBT 3? If so, then would these pipes be wrapped with an insulation in the control room?


Answer to my question - I found in Simon's layered drawing that the MBT 3 blowing pipes are attached to the side of the round casing to the MBT 3 vent valve...  Good work Simon!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Nov , 2017, 02:30
Hello Mr. Tore,


Have you and the wife made it back from the farm to the city? Things have been quiet on the website... I just wanted to make sure that you all are OK!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Nov , 2017, 02:59
Hello Mr. Tore,


I have updated the Bow Hydroplane drawing on page 195...  I know that I shouldn't let my mind wonder! But, If the Bow hydroplane operator in the control room had to switch to manual controls, then the clutch on the spindle is engaged with the manual drive gear.


Later after a repair is made, then the electric motor clutch may be engaged again.  However, there is the location of the resistive network which is driven by the motor shaft and may not indicate the correct hydroplane angle.  It is not likely that the clutch will be engaged at the previous hydroplane angle when it was dis-engaged...


How do they reset the bow hydroplane angle to match the mechanical angle indicators?  I'm thinking it has to be done at the resistive network unit because it needs to reflect the present hydroplane angle...


Regards,
Don_


PS - At NCR (National Cash Register) we had a punch mark to align timing gears on mechanical registers. They could bring the hydroplaned to indicate 0° on the mechanical indicators and then un-mesh the Resistive Unit and get it back into time with the hydroplanes where the electric indicator now reads 0°?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Nov , 2017, 03:49
Hello Mr. Tore,


I believe the answer to the Hydroplane timing issue may be very simple...  After engaging the hydroplane drive motor clutch - The resistive unit may have hard internal end stops and a slip drive clutch; where the hydroplane operator sets the hydroplane to a hard full up, and then to a hard full down. That should time the resistive unit with the hydroplanes again.  At least that's the way I would do it...  What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Nov , 2017, 00:30
Hello Mr. Tore and all,


I have uploaded the latest version of Skizzenbuch into my Dropbox folder. I have verified to the best of my ability about 2/3rds of the book and updated the torpedo section with new material.  Maciek was the expert in this area, and I believe he would be proud of his student's efforts...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 30 Nov , 2017, 23:21
Hi Mr. Don,
when do you think that the materials you are collecting and producing will be available for all U-Boat enthusiasts ?
I try to collect the crumbs of your fantastic work from the various threads of the forums, but I'll look in advance for the complete work...
Thanks anyway for your research....
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Dec , 2017, 12:29
Hi Filippo,


I sent an email to the Naval Institute Press yesterday evening and I believe I should receive a reply on Monday or perhaps Tuesday... Things have been dragging-out with these publishers; they seem never to have any priority when it comes to books. I will post more info later.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Dec , 2017, 01:09
Hello All,


I did get a response from the Naval Institute Press as follows:


Don,
 
We are still reviewing the work. The length does present a challenge but we’re not sure two volumes is the best solution. Will be back to you when we have a final decision.
 
Best regards,
Paul
 
Paul Merzlak
Editorial Director
Naval Institute Press
U.S. Naval Institute
291 Wood Road
Annapolis, MD  21402


So, we'll see what happens....
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 09 Dec , 2017, 05:22
Hi Don,

Thanks for the update. I'm keeping my fingers crossed for you.

Cheers,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Dec , 2017, 03:16
Hello Mr. Tore and All,


I am up to page 409 on my proof reading.  That doesn't mean it's all exactly correct in all cases...  Simon just found an error back on page 42! I had the top of the Q Tank drawn with a high ridge which only applies to FBT 2 and FBT 4. I corrected the drawing error and added the round flowing tank top.


I uploaded the latest version of Skizzenbuch to my Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: David83 on 16 Dec , 2017, 10:01
Maybe this helps too i found this picture in an Book its of building U238
Exhaust outlet can be seeing very good it has another flange in the ground part .

br David
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Dec , 2017, 01:08
Merry Christmas and Happy New Year - May next year bring all joy and happiness and friendships that last forever...


Kind regards,
Don and Maureen Prince
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 20 Dec , 2017, 03:57
Thanks Don and wife.....many wishes from Padova, Italy....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 20 Dec , 2017, 06:05
Merry Christmas
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Dec , 2017, 03:07
Hello Mr. Tore and All,


I have completed my reviewed and corrected Skizzenbuch and posted the latest version into Dropbox...  I also posted the latest images in the "Files Folder"...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Feb , 2018, 21:05
Hello Mr. Tore and All,


I have had several email exchanges with Mr. Tore over the past few weeks and have learned quite a bit about the setup and procedures for starting the Diesel engines and would like to pass-on the knowledge...

*********************************************************************************************************************************************

The training manual on the uboatarchive.net website that was provided by me (Don) and translated by Maciek only has only one mention of a flywheel.  This is on a page that has a drawing of the drive train...  The flywheel is on the back side of the crank shaft near the operating panel and it does not look to be a huge mass???

With your help, I'm beginning to understand that the main clutch is already engaged with the diesel engine during startup. This is a new concept to me, as I was concerned about starting the diesel engine on compressed air and getting the required RPM with the added mass of the clutch and the e-motor armatures during a compressed air starting procedure! This configuration will relieve the main diesel clutch of any undue friction on the clutch cones during startup; the cultch and dual e-motor armatures contribute to the mass as a flywheel to balance out any vibration (virtually a flywheel on both sides of the crankshaft).

1.  So, it looks like the main clutch on the diesel engine side will not get the initial friction load like I was considering during startup and coming online with the prop. However, it now looks like the clutch in back of the e-motors will take on that initial friction load when engaging the prop.  But, most of the masses on the drive line are already in motion, therefore the smaller mass of the aft drive shaft, the prop, and the water resistance to the prop spinning are not of a great concern (overall a much smaller mass for the e-motor clutch to handle).

2.  My take away from our discussions about the main clutch at the diesel engine is that this clutch is engaged before starting the diesel engine and disengaged after stopping the diesel engine. Therefore, the only variation would be a possible emergency manual clutch engagement or disengagement...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Feb , 2018, 01:24
Hello Mr. Tore and All,


I just uploaded the latest version of Skizzenbuch into Dropbox... I updated pages 420 through 422 covering the "Clutches."  Any comments will be appreciated.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Feb , 2018, 22:49
Hello Mr. Tore,


Congratulation!!! Norway crushed the competition at the Winter Olympics in Soul South Korea with a medal count of 39, Germany came in a distant second with 31, then Canada with 29, and the USA with 23, and the Netherlands with 20.

This was the final count...

Regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 24 Feb , 2018, 22:55
We still have to play ice hockey today.  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Mar , 2018, 03:43
Hello All,

I just got this email from Mr. Tore....


"Don I am currently in hospital for a stroke. In spite of my age I am hoping to be home after Easter if everything goes right.

Tore"

Let all keep Mr. Tore in our prayers and hope for a full recovery...
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: falo on 14 Mar , 2018, 09:20
Hi Don,


thanks for the information.


@Tore: Please get well soon.


Regards
falo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 14 Mar , 2018, 13:19
Hello Don,

Thanks for passing on the news. Please pass the warmest regards from all of us the next time you are in contact with him by email.

Cheers,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 14 Mar , 2018, 15:59
Tore, get well soon.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 17 Mar , 2018, 14:04
Dear Mr Tore.
I am new to this forum but see that for 6+ years you have been able to share and pass on some fantastic first hand insights into the operation and daily life on an ex working Norwegian Sub/ German U boat.
This information is invaluable for future generations so thank you.

Please take the time to rest and recuperate, your health is always most important.
Best
Mike

New Zealand
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Mar , 2018, 03:03
Hello Mr. Tore and all,


I don't expect Mr. Tore to respond to this posting because he is still in the hospital recovering from a stroke (Get well soon because I miss you). However, I am just posting some of my findings about the main clutch in the e-room. If you first examine the photo from u-historia.com they identify the levers function as to engage/disengage the main clutch [see photo 650 - page 419 (1).png].


Look at at image [Manual Type VII C (1).jpg] which indicates the main clutch is a friction type clutch similar to the diesel clutch. This seems to eliminate the possibility of the main clutch as being a "Spring Wrap Type Clutch" in the e-room.


Now look at the photo [Hebel3(2).jpg] which has detail not seen before. I have marked how I believe this lever in the e-room works. It looks to me as the lever is raised and the lever dog engages the gears wheel in the aft section of the clutch and possibly stops the drive shaft from being rotated when the Diesel engine is stopped. Therefore, sea water washing over the prop cannot turn the drive shaft. Is this the brake that is shown in the "Manual Type VII C(1).jpg?


These are only questions that I have and I'm looking forward to more photos. Reference photo Hebel2(1).jpg...  Are there any suggestions from others that read my observations?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Mar , 2018, 00:04
Hello All,


Just a quick note about Mr. Tore...  He is out of the hospital and back home in the city.  He has some issues with his right side after the stroke, but he is having therapy and said he hopes to have his driver's license back in September and be back to normal. I'm sure we all wish him a speedy recovery...


Regards,
Don_


PS: If anybody has any basic questions about the Type VII C U-Boat, then I would be glad to provide you some of Mr. Tore's information that I have documented in my Skizzenbuch. I believe some of the previous posted images may have been lost during a website upgrade.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 31 Mar , 2018, 01:16
Glad to hear he is back at home so he can search for eggs on Easter Sunday.  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Apr , 2018, 19:00
Hello All,


Just a quick update on Mr. Tore's progress after his stroke - He is going to physical therapy about three times a week and exercising at home, and it looks like he will be able to drive his car in a few months.  You just can't hold a good old barnacled U-Boat seaman down...


Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2018, 21:47
Hello All,


Great News! It looks like Mr. Tore has completed his physical therapy and has gotten back his drivers license.  Now he is off to his farm for a summer vacation...


Regards,
Don_



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Jul , 2018, 01:10
Glad to hear that  :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: 42rocker on 03 Jul , 2018, 19:42
Great news. Thoughts and Prayers. 
 
Later Tim
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2018, 09:06
Yes I am back and are possibly able to answer questions. I had to move back to civilization as my wife fell asleep while driving her car, totally wrecking it. Luckily she only broke her hand but got to be in the hospital for some time hence my stay in Oslo area.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 08 Jul , 2018, 04:56
Nice to hear you are back and recovering
I hope you wife is ok too.
Thank you for all your years of invaluable  knowledge and may you have many more healthy years.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jul , 2018, 09:09
I see quite a few question were raised while I have been away. One is about the valvehandles in the E-room under the switch table. An often forgotten details is the rather complex seacoolingwater system in the E-room, complex because there are so many alternatives and very narrow. Below is an extract of the coolingwatersystem in the E-room plate 13 showing the cooling og the Emotors/generators, Michell thrustbearings, sterntubes and compressors. I have only explained the port system for the e-motor /generator as we have dealt with the compressors before. The maininlet for the coolingwater pump is on the port side and the outlet is on the stb side. As mention before the system can be served by the pumps in the controlroom as well.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jul , 2018, 16:26
Hello Mr. Tore,


Great answers as usual... Recently, I got some photos of the objects below the Port Switchboard and have attached them for a discussion...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jul , 2018, 22:12
Hello Mr. Tore,


Best wishes for a full recovery for your wife... My wife Maureen who has never caused an auto accident says I'm a terrible driver and I drive way too fast! Tell her you love her, and we all hope she comes home very soon...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2018, 00:40
Thanks for good wishes, my wife and me are doing fine by together using the parts of our body which are working. Feeling a bit like KNM Kaura -U 995 having parts gradually detoriating and being renewed, possibly not up to the original standard. Like the U 995 anchor bay f.inst. which as many of your accurate modellers have noticed have been misplaced about one frame aft on the Revell kit and the museum U995 at Laboe which for some reason has been equipped with an anchorfluke homing pad which never was there on the original U 995. See my image below. ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jul , 2018, 03:32
Hello Mr. Tore,


When I look at Plan 13 the cooling water system, it looks like Cooling Water Out valves on the starboard side are always open to have the water flow through the e-motor coolers, bearings, thrust bearings and Junkers compressor. Then when the U-Boat dives, the valves are opened on the port side to provide the cooling water for the stern mechanisms, plus provide cooling water for the diesel engines towards the diesel room.


When running silent, would they ever shut off the cooling water pump?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jul , 2018, 04:10
Hi Don.
I cannot state for sure how they did it in the German navy in WW2, but in my time all our submarines, including the VIICs, had annual noisetrials in a Scotish loch where the sub was semi submerged surrounded by sofisticated microphones. Each auxiliaries on silent mountings was operated separately and a complete soundgraph for the machinery (included pumps of course) was made. We knew exactly which auxilliarly we could operate.  At silent running we only operated those auxs which were within the approved silent range. This was usually the coolingwater pump in the E-room.  The trim pump (piston) we sometimes used the crew for sifting the trim as the pump sometimes could be too noisy in spite of the silent mounting.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jul , 2018, 07:41
Hello Mr. Tore and All,


I have uploaded the latest version of Skizzenbuch 11 x 17 - M + I.pdf into the Dropbox folder. Pages 33, 125, 126, 127, 128, 426, 427 have been added. However, there is no index because I am in the progress of creation a new one. Please advise if anything looks to be incorrect... This looks to be the final version except for any required corrections.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 11 Jul , 2018, 18:29
Hi Don
Just to clarify for me as I see you have all been working on this for years.
 The Skizzenbach is a book and is the dropbox file a private box for you guys whilst you are working on your project?
Also will the Skizzenbach be available later for public viewing/purchasing etc?
Thanks
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jul , 2018, 22:18

Hello Raymic1,


So far "Skizzenbuch: U-Boat Type VII C Project" is my attempt to create a book that informed the reader about almost all aspects of the design, functionality,  and operation procedures of the German WWII Type VII C U-Boat. In the beginning - a few years back, I had a contract with Schiffer Publishing for the book. However, they cancelled the contract about two weeks before I was to get my author's proof copy of the book. Looking back, the cancellation was probably a good thing because I have made many changes and corrections to Skizzenbuch. I have been looking for a new publisher ever since, but with no success because most publishers say the market is too limited and the book is expensive to publish.




Skizzenbuch requires a format size of 12" x 7.75" - Landscape at a minimum, and the page count is about 510 pages including the index and at least three (3) fold-outs sheet in the back of the book. I have suggested to various publishing companies that Skizzenbuch should be a two (2) volume set. There are well over 700+ color photos and original German mechanical and electrical schematics in the book.


If I can not find a book publisher, then I may eventually go it alone... By that I mean - I could go to the expense to U.S. copyright Skizzenbuch, create an LLC publishing company and purchase the software to copy protect a downloadable file. Most likely the file will be free, and I could get books printed on demand but they would be very expensive. I am a 77 year old retired NCR Plant Maintainability & Support Engineer and Computer Hardware and Software Support Engineer with over 46 years of experience... However, I am NOT wealthy!


Kind regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 11 Jul , 2018, 22:38
Wow...thanks Don. That clarifies for me and I'm in awe of yours and Tores and others dedication.
In regards to complete accuracy my opinion is that given the incomplete and lost knowledge due to the loss of documents and time frame, most books already in circulation and all experts still have mistakes.
So even if mistakes are found when you release yours, the Uboat community would be very happy with any concise information and other experts would no doubt take up the challenge of continuing this as an ongoing works in progress.
And I for one would be happy to pay a fee for the PDF version if a full book was prohibitive.
I'm sure the rest of the Uboat community grateful for your efforts would also agree.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 11 Jul , 2018, 23:28
I completely agree with Raymic...I'm sure that many U-Boat enthusiasts would be happy to pay a fee to have the PDF file and print it on their own...
Please, Don, not disperse all that material and make available, as soon as possible, the PDF file....
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 12 Jul , 2018, 03:40
You could publish it via a print on demand service.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 12 Jul , 2018, 05:28
Hi Don,
in any case, in my opinion, the right thing to do is to make available the material in your possession for all U-Boat enthusiasts...
I suggest that you contact an expert in file sharing and find out a solution that safeguards your copyright and availability for interested parties too....
I'm very, very interested...
Respect.
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2018, 05:41
Don.

Skizzenbuch page 125 Schnorchel system. I guess you have been confused by two system. The VIICs schnorchel system comes in two version, the old and the later improved system. Below is my image showing the two versions. If you look at the old system it is full of bends, hence resistance, the new system elliminates the schnorchel airpipe alongside the diesel air trunk by introducing the schnorchel air straigth in to the dieselair trunk, otherwise I guess the image is shelfexplanatory.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2018, 10:30
Don

page 126
You are describing a diesel cycle calling it two cycle, four strokediesel. I guess this is a confusion as the VIICs have two four stroke supercharged medium speed dieselengines. Unless I have misunderstood you , I suggest you omit the paragraph dealing with this dieselcycle.

page 127
The dieselengine coolingwater outlet leave the engine to the exhaust bend coolingjacket, before leaving the engine, part of the coolingwater flow is manually adjusted to the correct watertemperatur read at a local thermometer to the exhaustvalve cage coolingjacket. This has nothing to do with the exhausttemperatur, only to cool the exhaustvalve cage seating to prevent burning.


As to the watercooled exhaust manifold which is having a water jacket all the way to overboard it is easy to be confused by the numerous venting and drainingpipes of the cooling waterjackets, non of them are used for draining a flooded exhaust manifold. At the bottom in the aft end of the exhaustmanifold is a drain pipe to the bilge this is the only drainpipe to the inside of the manifold used for draining a flooded manifold. This drain pipe is unfortunately not shown on plate 13. The drain of the inside of the group exhaustvalve is shown on plate 13.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2018, 12:39
Don.
May be it gives a better understanding to see a crossection of a typical watercooled exhaustvalve cage.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jul , 2018, 21:45
Hello Mr. Tore,


Page 125 - My intent on that page was to show the huge size of the diesel air intake trunk (dark blue in Simon's drawing). Then to compare the smaller schnorchel air feed line attachment to the diesel air intake trunk. The schnorchel head air intake feeds air through the mast to a bend (newer design) or a pipe on the port side of the forward bridge (older design). Either way, the air intake from the schnorchel mast is limited in volume as compared to when running on the surface and taking air via the diesel air trunk. In addition, the compartmental air intake and exhaust stacks are shut when the schnorchel is in use; further limiting the air supply to the U-Boat.


Therefore, the air resource is limited when the schnorchel is in use...


Should I add some of the above comments to clarify and to better understand page 125?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jul , 2018, 00:42
Don.
You are right in stating the major air restriction is in the float air intakevalve and the schnorchelmast, however the new system improvement was connecting the smaller schnorchel air pipe to the diesel air trunk close to the diesel air main intake valve thus eliminating the long narrow schnorchel airpipe all the way to the main inlet valve in the engineroom. The sketch might be a bit misleading with regard to the new system as it does not show very clearly the airpipe from the schnorchel mast is entering the large dieselair trunk close to the dieselair main inletvalve thereby utilizing the dieselair trunk also for possible waterintrusion. I am enclosing a revised image below. When schnorcheling you had, as you state, a limiting factor as to the speed and load of the engine. Speed because of the strength of the mast, dieselload (generator load)  because of the airconsumption. The control was monitored by the barometic pressure in the compartments, the pressure fluctuation you could feel in your airdrums.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2018, 01:20
Hello Mr. Tore,


As stated by U-480's captain, they had to use many CO2 canisters while schnorchelling (I guess they were under water more than on the surface). In that situation, I would assume they had to run both ventilation blowers. Did you experience the large use of CO2 canisters while onboard of U-995?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jul , 2018, 02:00

Don
We did not use any CO2 cannisters while schnorcheling, in fact generally the air quality improved as the diesels consumed the very quickly the fouled air. The problem were more individually some could not take the pressure fluctations, a few even experienced a bursted eardrum. Another experience was people with bad toothfillings experienced overpressure under the fillings creating some pain.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2018, 21:36
Hello Mr. Tore,


I uploaded Skizzenbuch with corrected pages 125, 126, 127, 128, 426, and 427 into Dropbox... Again let me know if it is OK?


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jul , 2018, 00:22
Don
I`ll look into it soonest, but for the week end I take my wife to the coast to relax after a hectic week for an old man. Hopefully back on monday.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jul , 2018, 00:44
Hello Mr. Tore,


Of course, you and your wife enjoy the beach and the weekend... How is her broken hand? Is it in a hard cast or a bandaged wrapping?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jul , 2018, 01:17

Unfortunately they had to remove the hard cast as the parts were not matching correctly, redid the whole thing without cast and she got a lot of painkilling medicines and as usual a lot of side effects. But we are doing fine and shall be back next week.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2018, 01:40
Don Skizzenbuch Page 125.

I guess you should use my latest sketch, showing the diesel air duct coloured ligth blue all the way from the schnorchel air connection up to the engineroom main diesel air valve. From the latter valve the diesel air duct splits in two, ending in two large rectangular outlet between both engines and the pressure hull. When schnorchelling and in rough wheather surfaced, the seawater gushed down to the bilge far away from the air intake of the engines.  When the main group exhaust hull valve has a massive leakage which often occurred (in spite of the pneumatic grinding) there is a leakage chamber in the housing which can be drained to the bilge to prevent filling the exhaust manifold alongside the engine. Eventually the exhaust manifold alongside the engine has a possibility for a drain fore and aft to the bilge. These are not shown on plate 13 and can be easily be confused with the many coolingwater drain in the system.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2018, 04:30
Don Skizzenbuch page 127- 128.

I guess there is a misprint in the firing sequence of a 6 cylinder diesel which is cyl no 1-5-3-6-2-4.
The indicatorcocks are shown on the lower right image (not left).

Exhaust temperatures. You mention the coolingwater regulator is adjusted manually to keep the exhaust temperatures below a set level. I don`t think the exhaust temperatures are controlled in this way, but the materials of the components. Exhaust temperatures are controlled by the timing, combustion (load)and used for monitoring the  condition of the fuelinjection system, exhaustvalve seating etc.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2018, 05:19
Don Skizzenbuch page 427
I guess in the general description of the Michells thrustpads you should mention the shaft thrustdisc pushes on the forward thrustpads when the shaft rotates in ahead direction.

I  think the main reason for a submarines tailclutch is to disengage the propeller while charging the batteries along side, you don`t disengage the propeller for starting the dieselengines, unless you are alongside, think about all the old reversible diesels.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2018, 16:17
Hello Mr. Tore,


If the main clutch is engaged and you are starting the Diesel engine, then you are adding the additional resistance of the prop/seawater which would be driving the U-Boat during startup. Is this not an extreme amount of load during startup? I don't doubt your answer, but I just want to verify the startup procedure...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jul , 2018, 00:52
Don.
Most of the marine diesels in world are starting with a fixed blade propeller directly attached to the engine. Having a tailclutch is an exception rather than a rule. A direct reversible diesel as installed on the older VIICs had a manoeuvre sequence as follows: Starting with propeller engaged driving vessel ahead, manoeuvre astern, stopping the dieselengine, reversing the engine by axially shifting camshaft, starting the engine running astern, all manoeuvres carried out with the propeller engaged. This is standard manoeuvre for most of the marine diesels with fixed blade propellers, nothing special.
 Starting the diesel engine with the propeller engaged and submarine moored alongside might have a consequence, like one of my first battery charging alongside. We were alongside in a remote harbour way up north of Norway, we were moored at a wooden quay right in front of a shrimp peeling factory, built on wooden poles. I was on the bridge asking the engineer in charge if everything was ready for charging, got confirmation OK and ordered start the engine. Good old Kaura ex U995 made a jump ahead broke the moorings and ended up underneath the shrimpfactory while all the ladies working there ran screaming out of the shaken factory. The engineer in charge had forgotten the tailclutch.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jul , 2018, 01:14
Don
In addition to the above it was very convenient for the engineroom crew to have a tailclutch f.i. when having an engine repair and we wanted to have a testrun. With a propeller engaged you had to ask the officer on watch to double up the moorings prior to the test, with a tailclutch we were our "own masters" and could just disengage the propeller.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jul , 2018, 03:27
Hello Mr. Tore,


Thank you for the information on the startup sequence, and I was very amused about the shrimp factory story.  Things like that do happen in real life!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 17 Jul , 2018, 05:06
Hi Tore, do you know when they gave up the direct reversible diesel engines? (which boats were the last ones?)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jul , 2018, 09:18
Hi!

It`s a good question of which I have no concise reply. On the VIIC 41 like  U-995 they did away with quite a lot of weigths as the greater diving depth caused a lot of weight increase hence they removed some equipment including the reversing mechanism, but ordinary VIICs in our fleet had non reversible engines as well as KNM Kaura ex U 995. So we can`t assume this is the reason when looking for the boats with reversible diesels. If somebody should feel for making a research a very visible sign that the engine is a direct reversible type is the reversing cylinder up front of the engine as can be seen on my image below may we could trace the boats based on engine photos.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jul , 2018, 09:43
Further to my answer above I realize my image was not very clear so here is a photo of the real thing.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 17 Jul , 2018, 13:16
I guess pictures of the diesel engines of the different boats are rare and hard to find.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jul , 2018, 16:57
Hello Mr. Tore,


I was wondering (I know that could be dangerous) about conserving fuel... Running on 1 diesel engine and free tailing the opposite propeller looks to be the most economic way, but the rudder would be needed to maintain the course. Then again, they could be driving with 1 Diesel engine and using its e-motor as a generator to power the opposite e-motor to drive its propeller drive shaft; possible the rudder may be in use as well... Since the driving Diesel engine is getting resistance from its e-motor acting as a generator; does this mode cause more fuel use?


I believe both options are viable... Do you remember using one or both options, and which is the most economic?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jul , 2018, 17:03
Hello Mr. Tore,


I updated pages 426, 427, 428, and added the index back to Skizzenbuch. The latest version of Skizzenbuch is in the Dropbox folder...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jul , 2018, 00:41
Don fuelconserving.

You are entering into a very complex area in the operation of the submarine diesels, introducing many  unknown elements as the submarines variation in water resistance related to the speed, propeller efficency in relation to revs., dieselengine variation of specific fuelconsumption related to the bmep ( brake mean effective pressures) etc. We did not have access to all these figures so we did not have any instructions as to the variation in the operation modes.
The specific fuelconsumption is usually measured at the testbed using a waterbrake, following the theoretical propellerlaw, the result is not always matching the real thing onboard, certainly not on a submarine having so many variables. In your proposal you introduce a load which increases the BMEP outside the propellerlaw graph (waterbrake).  I have no figures, but should imagine your theoretical suggestion could be viable, but you have to watch your engine (exhaust temperatures) carefully not to overload the engine (excessive BMEP). I don`t think you should include this topics in the Skizzenbuch, its a topic for the real theoretical experts.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jul , 2018, 01:33
Don Skizzenbuch page 426, 427, 428.

Checked OK. May be you should use ahead pads and astern pads for the Michelle thrustbearing instead of forward pads and aft pads.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Jul , 2018, 09:58
Hello Mr. Tore,


I took your advise and changed the thrust pads to ahead and astern...  I was not going to add the info discussed about fuel economy running. I was just curious...


Also, I updated Skizzenbuch to reflect the changes in Dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jul , 2018, 10:21
Don, very good. As to the very complex picture of fuel economy and the many way of operating dieselengines-generator/E-motor I guess it would have been an interesting thing for an IT man to make an optimal programme for the various running modes with the numerous variables.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 18 Jul , 2018, 23:45
Hi Don and Tore,
I was wondering when you expect to finish the work on Skizzenbuch.
You know that there are several U-Boat enthusiast waiting for the availabilty of your work, obviously paying for it...
The problem has already been addressed, and one possible solution is to make a file available and printable on demand, upon payment.
What do you think about ?
An answer would be welcome.
Respect.
Fillippo from Padova
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jul , 2018, 00:44
Hello Fillippo,


As far as I'm concerned, "Skizzenbuch: U-Boat Type VII C Project" is complete. I do not plan on adding anything to the 516 page document. Possibly some grammar corrections and having the two (2) pages allocated as a foreword done by a friend.


A book publisher Casemate Publishers UK is looking at Skizzenbuch as a possible e-book in a PDF Format. They have downloaded my full PDF file "Skizzenbuch 11 x 17 - M + I.pdf and will let me know their decision in about 2 - 3 weeks. 


However, if they decide not to publish the PDF, then I will absorb the expense by getting a US copyright ($55.00 for multiple authors) and create a US State of Georgia Publishing Company LLC ($150.00) sometime in November or December of this year. Then in January, I will purchase CopySafe Software ($295.00) to protect the distributed free PDF file.


Free distribution may be done through several websites to be determined...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 19 Jul , 2018, 19:59
Fantastic Don.
I hope this all goes well.
Look forward to getting it in some way soon.


Ps I hope Casement don't put it out with a massive premium. As a unique specialist tech doco I'm assuming in hard book form it would be quite expensive. I wonder if the PDF from them will be the same.?
Cheers
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jul , 2018, 23:58
Hello Mr. Tore,


U-96 had an early bridge/tower design that had air stacks on the inside of the bridge, and intake stack windows/panels on the outside of the bridge. These stacks are for the diesel air supply. However, there is the diesel air stack under the winter garden in back of the tower with a mushroom type top valve. I don't believe there was a connection between the two? Was this just a means to get air below the winter garden? It looks like later bridge/tower designs eliminated the two bridge stacks...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jul , 2018, 06:36
Don.
I don`t think there is a connection, the dieselair main input is the main disk valve on top of the diesel air duct inside the tower casing and the towercasing inlet ducts are merely to ensure sufficient air access to the void space inside the casing. Likewise the external ventilation ducts have the main inlet (and, in the older version, outlet) inside the towercasing. There are some variations in the arrangement particularly after the introduction of the schnorchel system. In spite of the well protected inlet of the dieselairduct a substatial amount of water entered the engine room bilge in rough  weather, this is one of the reason the external ventilation duct is separately from the large dieselair duct as you want to avoid water intrusion to the electric fans. The ventilation inletvalve casing had a special drainage system to the controlroom bilge as well. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jul , 2018, 06:47
Don
The reason for the complicated arrangement of having separate ducts for the various air inlets is if you would have the inlet for the diesels via f.i. the bridgehatch the large diesels would created an excessive "draught" through the bridge hatch making difficult to use as an access hatch.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 20 Aug , 2018, 20:49
Hello Mr Tore
You may be interested in a recent discussion with possibly an old shipmate Mr Ludvig Haga a Torpedoman on Kaura.
Sorry the link below printed very small..


https://www.facebook.com/groups/U.Bits/permalink/2151611101831613/ (https://www.facebook.com/groups/U.Bits/permalink/2151611101831613/)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Aug , 2018, 01:45

Very interesting, I checked my papers but regret I can not find a torpedoman with the name Ludvig Haga, neither can I remember any person with this name onboard in my time. KNM Kaura came into service as a frontline boat late 1952 and was taken out of that service latter part of 1954, practically the whole time I was onboard. After a refit 1955/56 she became a training vessel and of course a lot of people not known to me sailed with her in that periode. It would have been very interesting to see his discussion but the link you gave me leads to,I assume a russian, named Boris Nakropin, being administrator of a group Everything for Uboat scaling modelling. May be I am doing the wrong thing here, as my IT knowledge is not the best in the world going on 90. ;D
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Aug , 2018, 01:47

Sorry my image was too big, here`s a smaller version.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 21 Aug , 2018, 03:08
Ah yes sorry Tore.
I am a member of Ubits Facebook site admin is Boris. He also makes a lot of Metal etch Uboat modelling bits.
Also  I guess that link would not work for non member as you are.
Ill see if I can copy and paste his brief comments.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 21 Aug , 2018, 03:18
https://www.facebook.com/ludvig.haga


Mr Tores. Above is his Facebook profile and it was not much of a conversation. But he said he was onboard 59-60 so he may have missed you.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Sep , 2018, 03:09
Weathering VIIC

As many of you have noticed I am not in favour of the overdone weathering  on some models. In my time (peace) there was hardly visible rust and damage to the hull which was not repaired as soon as we entered harbour. Major damage to the casing happens to me only once on U 995 where we in the North Sea got some 4- 5 meters on the starboard casing smashed in by the November gale. Below are a few images which might enlighten you on the subject. First of all the most visible part for weathering is the casing and (U 995 wooden)deck. A vital detail is that the deck should be dark grey and one of the instruction from the German High command was always to patch up any damage by the dark grey paint. The reason is obvious, air surveillance.

The casing  is made by galvanized thin metal plating riveted by small rivets using alongship joggle joints as can be seen on my image from an inspection of U-995 I made in 1953. The joggle joint is clearly visible but hardly the rivets, corrosion is minimal.

I enclose my latest paintinting of KNM Kaura ex. U- 995 where I have indicating the normal weathering after approximately 8 months service under rough condition above the artic circle in the Barentz sea.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 11 Oct , 2018, 06:57
Hello everyone!  Hope you have all been doing fine.

I have a question about operating the uboat. I know that the ballast tanks should be either empty or full. Keeping them partially flooded was not intended.
https://uboat.net/forums/read.php?20,91306,91308#msg-91308 (https://uboat.net/forums/read.php?20,91306,91308#msg-91308)

This brought me to the question. If there were no gauges that showed the water level of ballast tanks then how did uboat crew member knew when to stop applying compressed air to a ballast tank?
Blowing all the water 100% out of the tanks would be also dangerous since you would produce bubbles? Also the danger of wasting compressed air when blowing an empty tank. How did the ballast tank operator know when to stop blowing?
Did this happen by pure experience or were there any sound cues?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Oct , 2018, 08:03
Karel.

Blowing the ballasttanks is done under different circumstances and you are using instruments and experience. F.inst if you want to ascend by ballasttanks from larger depths say 50 meters you use more precious HP air as the counter pressure would be 5 kg/cm2. It takes an experienced controlroom engineer to admit the right amount of air into the ballast tanks which are never blown empty at this depth, the controlroom engineer uses the blowing pressure, the counterpressure ( depth), the time and experience admitting the right amount of air. The aim is just to blow so much air into the the tanks so the submarine start to ascend, then shut the blowingvalve and the air in the ballast tanks expands, forcing out the ballastwater. As the counterpressure reduces it increases the acceleration of the ascend. If you blow too much air into the ballasttanks the tanks are empty before your uncontrolled ascend which is waste of energi, a lot of bubbles and dangerous as the sub break the surface without control. The correct ascend is:  you take the sub up to 14 meter by hydroplanes, make a surface sweep with the periscope and then blow your ballasttanks controlled by checking the depth gauge, stop blowing before completely surfaced, then start the diesels and blow the residue air by the diesel exhaust. The exhaustblowing is done in a special sequence starting with the saddle tanks having the smallest resistance being almost at the surface. You are able to check the counterpressure (exhaust) manometer when the tank is empty but normally you checked when the exhaust escapes out of the Kingstons.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 11 Oct , 2018, 08:37
Thank you.  Makes sense and it also means i have to cheat for my game project a little since this kind of experience is hard to come to a gamer. Need to think how i can communicate this proccess to a player.  I attached a picture of gauges. These are modelled after photos but i have not yet found a proper source that would identify their purpose. Are you able to tell me what info these gauges presented?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Oct , 2018, 09:23

Your image of gauges does not make sense to me, but I assume it is a simplified HP blowing panel for the ballasttanks. I am afraid the real thing is a bit more complicated, but the original design idea is that you have a centralised Xmas tree with a main blowingvalve handle by which you can control all the mainballasttanks. Each main ballasttank has it own valve locally at the pressurehull which really don`t is used in the normal operation, hence it is left open. At the Xmastree you have separate blowingvalves for each main ballasttanks and other distribution valves which I have indicated on my image below, It might look complicated, but it makes a very flexible blowing system which takes time to study. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 11 Oct , 2018, 14:07
Tore.

Highly appreceate you taking the time. I studied your picture for couple of hours with additional material that i have gathered over the internet. Gauges on my image are indeed from blowing panel but i understand that i am missing many of them. Looking closely at other pictures i can see additional gauges between some valves. I decided to dive deep into the subject and try to understand as much as possible. This will give me best option to decide how to represent similar level of control in the game. I am not aiming for super  1:1 realistic but i do want the game system to feel authentic and somewhat believable.

I should start from the basics. Do i understand this correctly that air compressor was used to fill HP banks 1-5 with air? These banks were connected to HP air distributor. From there the air was distributed between ballast tank blowing distributor and LP air distributor.  Hope it is ok if i keep my questions short and go forward from there step by step. As every answer gets me a step closer to understanding this complex system and will help me form my sequential questions better. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Oct , 2018, 14:32

Karel. 
Below is the VIICs HP air system with the total air vessels for HP air storage, inside and outside the pressurehull. The scheme is a bit old as you have two conventional compressors, the normal VIIC execution had the Junker free piston diesel compressor replacing the conventional electric compressor on the starboard side in the aft torpedo room. Sorry for the many arrows crisscrossing the image.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 12 Oct , 2018, 02:10
Tore.

Can you tell me where it was possible to read the data on how much compressed air was left into HP banks? I cant seem to locate the placement for these gauges.  If i had to guess then i would say they are near the HP air distributor where the lines were connected to the banks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2018, 02:54
Karel.
The hp air capacity was monitored by the pressures for each vessel to be read at the air distribution rack, never the volume. The volume could of course be calculated acc. to Boyle Mariottes law, but was never done. All the storage airvessels were never connected to the distribution rack at the same time, only a few for normal use. One of the problems for blowing exstensively is of course the expansion temperature which might lead to ice formation at the blowing valve being used extensively so you had a limiting factor as to using this valve.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2018, 02:58
Karel.
The total capacity of the HP air banks is 3.900 liters at 205 kg/cm2
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 12 Oct , 2018, 09:31
Tore.

The HP and LP distributor both have a drain valve. I cannot find any good explanation about these. What are they for exactly? Draining water? From where?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Oct , 2018, 10:07
Karel.
When you are running a compressor you always collect water from the humidity in the air, particurlary on a submarine where the humidity is high. In view of the previously mentioned freezing at air expansion it is a good idea to keep the air ar dry as possible.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2018, 22:19
Hello Mr. Tore,


When using the Exhaust Manifold Blowing Valves in the control room would the proper blowing order be:
1. Blow MBT 1 and MBT 5 the highest tanks with less back pressure
2. Blow FBT 2 and FBT 4
3. Blow MBT 3 being the lowest tank with the greatest back pressure


Would there be a drop in the back pressure which would tell the crewman the tanks was blown, or could the crewman hear the gases escaping and know the tanks were blown?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2018, 01:16
Don.
Your suggestion as to the exhaust blowing sequence seems to be correct. You are not able to hear the exhaust escaping  through the Kingstons, quite often the people on the bridge reported when they observed the gas bubbles, but as everything else in the word, experience counts, an experienced engineer was able to tell when the tanks were fully blown by using his feelings. Normally you are not able to empty the ballasttanks 100%, you shall always have some residue ballast water left, however I never experienced any free surface effect from the ballast residue. I guess you guys making games for a conventional submarine with WW2 technique have your difficultes. The recorded WW2 parameters were scares and you had no computer to feed, old fashion experience, smell, temperatures and sound were important elements. I could be sleeping in my bunk when a change in the diesel sound woke me up and I was in the engine room before any messenger woke me up. Many things happened due to mishandling by unexperienced crew during the latter part of WW2 as the war had taken its toll and shortage of experience became a problem. If you look at the various intricate systems like the HP blowing system, engineers have developed same over the years and made modifications to be able to handle various situations. It took time and experience to handle all these options effectively which computers can do today, I guess it is possible to incorporate some of the elements by f.i transferring pressures into volumes in case of ballast blowing etc. to make the monitoring a bit more computer friendly but the real thing during WW2 was monitoring based on pressuregauges and time, the rest human senses and experience.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Oct , 2018, 13:53
Hello Mr. Tore,


Thank you for the quick response to my question... It is good to see that you are again on the AMP website with your expertise. Have you fully recovered from your stroke with the physical therapy? Has your wife recovered from her broken hand from the auto accident? It seems like you all have had some bad luck this past year. Let's hope that this coming year will be non-eventful and much better.


I have not heard back from Casemate Publishing about Skizzenbuch. I'll give then a few more weeks and if nothing results, then I will form my LLC, Copyright Skizzenbuch, encrypt the files and distribute it for free.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2018, 14:20
Don.
I am indeed recovering very well having an extremely beautiful female physical therapist holding a phd. on just my condition helping my recovery. Enjoying every minute of the treatment. May be a waste for an old fart like me going on 90. My wife has recovered pretty well thank you and we are planning our blue sapphire wedding, 65 years, end this month. I share your hope that next year shall be less eventful than this but hope your Skizzenbuch shall materialize.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 13 Oct , 2018, 14:49
Tore, I’m glad to hear your recovery is doing well (with eyecandy).


Don, why don’t you publish it on demand via amazon or other publish-on-demand services? It doesn’t cost you anything, the risk of piracy is gone because it will be printed and you will earn money for the years of hard work on Skizzenbuch. You deserve a compensation for the work. If there is any technical problem then I could try to help you.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2018, 15:30

Rigth now National Geographic is showing a movie WW2 : "A hell under water" about the first documented torpedo attack by a submerged submarine on another submerged submarine. The incident happen February 1945 outside the fishing village Fedje on the western coast of Norway and they use the museum U-995 for the interior scenes, not very successful as the people (crew) are twisting wheels and handles meaningless and would in real life probably have put the U-995 to the sea bottom. The German Milk Cow U- 864 having a cargo of mercury for Japan had some engine trouble and was schnorkelling when the bristish submarine of the V class HMS Venturer heard her and later discovered the schnorchel mast of U- 864. HMS Venturer had only 4 torpedoer and the CO of Venturer set the 4th torpdeo a bit deeper than the other 3 anticipated U-864 would make a classic escape by going deeper when they heard the torpedoes. U 864 was hit and sunk at 150meters depth all hands lost. U 864 still causes us trouble today as she has a substantial amount of mercury in her keel laying and polluting the seabottom outside Fedje. HMS Venturer became Norwegian and renamed KNM Utsira a few months later. Below is KNM Kaura ex U-995 in the same area during a dummy attack . Although we had a fruitmachine we used the old style of attack, me calculating the parameters for setting the torpedo.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Oct , 2018, 15:56
Hi VIC20,


I have not found an on demand publisher that will publish a book with the dimension of 12 inches x 9 inches with about 516 pages with a minimum of 3 fold-out sheets in the back of the book...  Let's talk about this off line and my email address is donprince5207@comcast.net and perhaps I'm not talking with the right people...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Oct , 2018, 19:47
Hello Mr. Tore,


When starting the diesel engine on compressed air... The starting distributor is directing air to push down on the cylinder head to cause crankshaft rotation. When the correct RPM are attained by running on air, the fuel lever is set to run and injecting fuel which causes ignition. At this point, there may be several RPM happening before the starting air distributor is shut off by the diesel engine operator. Normally, the diesel engine has both intake and exhaust valves shut during the power stroke, or the valves are shut when compressed air is injected into the cylinder to simulate the power stroke.


My question is with both valves shut and when fuel is injected into the cylinder and we have ignition; does the ignited gases feed back into the air distributer and eventually back to the starting air canisters, or Is there a check valve on the starting air distributer to prevent this feedback from happening? Or is the ignition gases feedback simply not a problem?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2018, 02:15
Don.
The starting system originally designed for a direct reversible engine is complicated as you have to start both in a ahead and astern configuration. If we begin with the starting valve in the cylinderhead,(I guess you called the piston for cylinder head in your question) it is a combination of mechanical and pneumatic operation. Below is an image of the valve which is operated by its own sartingcam on the camshaft. Normally the valve is shut by a spring lifting the pushrod free from the cam. First stage of starting is you open the starting air supply valve admitting starting air to the lower part of the valve. A branch off after the starting air supply valve supplies air to the starting manifold. First stage of starting is moving the starthandle one step, admitting air to the top of the starting valve, pushing the lever of the valve rod up thereby
engaging the valve rod roller with the starting cam at the camshaft, now the starting air is controlled by the camshaft. I guess you have to study the diagram below to understand it fully. Some parts of the diagram is for a direct reversible engine and a few details are not shown on the diagram.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: karel on 15 Oct , 2018, 03:56
Gentlemen.

Just to let you know. The new Das Boot teasers were released an hour ago. You can find them here.
https://www.youtube.com/watch?v=mZrL-JAmhVw
https://www.youtube.com/watch?v=XY1X6Z708aA
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Oct , 2018, 20:31
Hello Mr. Tore,


Does this writeup look OK? Note there is a time period where fuel is injected when the starting valves are operational. Again was there an issue with cylinder chamber back pressure gases into the compressed air canisters?


Regards,
Don_

Procedure For Starting The Diesel Engine With Compressed Air

1. Opening the starting air valve (RED Hand-wheel) and admitting starting air into the lower part of the starting air valve provides compressed air to the starting manifold and the starting valves. There are six (6) starting valves; one (1) per cylinder.

2. Moving the starting handle to the start position directs compressed air from the starting manifold to the top of all six (6) starting valves. This air pressure forces all six (6) guide links to pull upward and cause the cam arm rollers to engage the starting cams.

3. One of the six (6) cams will be at a low position and the guide link will move higher and force the starting valve to open and admit starting air into the cylinder chamber and force the piston in a downward direction. This piston movement starts the crankshaft rotation whereby other starting valves will continue this running on compressed air process.

4. After the required RPM is reached, move the left fuel handle from stop to a point beyond 0 the minimum (the maximum is 55) and then ignition occurs. Now, move the right starting handle to operate which results in the roller cam arms being lifted off the cams and the compressed air being vented at the starting manifold into the diesel room. Turn off the starting air via the RED hand-wheel on the starting air valve. At this point, the diesel engine will be run-up until the operating temperature is achieves and then put on-line at the commanded speed.

Shutdown – move the left fuel handle up from the amount of fuel to Stop.

In the photo of U-995’s right starting handle, it only has two (2) positions; run [at the top (Betrieb)] and start [at the bottom (Anlassen)], and the reason for this difference is because U-995 diesel engines do not have reversing. If it did have reversing, then there would be a reversing handle to the right of the starting handle as I have indicated in the modified photo. However, on U-995 if there was a need for reversing, then the e-motors will be used for that function. If there is a lack of compressed air to start the diesel engines, then they could use the e-motor to crank the diesel up to speed and then inject the fuel for ignition.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2018, 03:06
Don.
Below is a revised scheme of the starting system may be it clarifies the system a bit better.  As to your concern of the combustion gases entering the starting air vessel I dont think it is a problem as the starting air cams are timed to open the starting valve at an optimal piston position past the TDC during the compression expansion stroke when the cylinder pressure is lower than the starting air pressure (30kg/cm2). There is no fuel supply at this stage. However when you are moving the fuelhandle towards fuelsupply you are at the same time venting the upper part of the starting valve and the startingvalve pushrod  is removed from the camshaft and the valve is shut by the spring.  Some times you obtain a supercharging effect by the starting air. Furthermore as far as I remember the startingair supply valve is a NR valve. This starting system is very conventional and is even today operated in thousands of dieselengines.

On some simple semidiesels you actually fill the starting air vessel by the combustion gases allowing same to enter by the starting air pipe.
I once had an incident where due to a mechanical failure  the starting valve stuck open. The result was overheating of the pipe, not very dramatic, only some brown coloured paintings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Oct , 2018, 13:35
Hello Mr. Tore,


This video shows a German Diesel engine and other components clutch and generator at the end of the video...

https://www.youtube.com/watch?v=zLfa43_1WH8 (https://www.youtube.com/watch?v=zLfa43_1WH8)

It looks like at the beginning the one person is pumping lube oil through-out the engine before starting with compressed air. I believe they started the Diesel engine with the clutch engaged and connected with the generator.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2018, 23:18
Don.
The starting procedure of a smaller MWM diesel seems to be a bit cumbersome, but in principle correct. On a VIIC GW engine you use the electric stand by lubeoil pump to put up the lubeoil pressure before turning, then you turn the engine by air with open indicator cocks, blow trough as we called it, before the starting procedure.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Oct , 2018, 14:32
Hello Mr. Tore and all,


We have a real author among us... Dougie Martindale's book "Gunther Prien and U-47: The Bull of Scapa Flow; From the Sinking of the HMS Royal Oak to the Battle of the Atlantic" will be available on Amazon on November 1, 2018. The publisher is the Naval Institute Press and Amazon's listed price is $28.03, and you can pre-order the book. I have just ordered my copy...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2018, 03:31
Hello Mr. Tore,


Question about exhaust blowing MBT 1 and MBT 5... Assuming the U-Boat is in a fuel oil configuration with FBT 2 and FBT 4, then we blow MBT 1 and MBT 5 with exhaust gases. Are they both blown at the same time, or do we blow one of them at a time (Which)? I think we would blow MBT 1 first because of an emergency dive situation...  Just checking....


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2018, 04:13
Don.
The exhaust gases take the easiest way, eg. where you have the smallest resistance. Depending upon the trim of the submarine at the end of the blowing you make your choice as to which sequence you are blowing. If one of the MBT is empty before the other you shut the exhaust blowing to same while blowing the other, if not, the exhaustgas shall escpape via the flood gates of the MBT already empty and you would`t be able to drain the other MBT completely. The exhaustblowing is "surfaceblowing" and is the final touch of the surfacetrim. In fact you have the same effect blowing by air at larger depth. Hence you have to take in to consideration the trim of the sub while blowing , f.inst a bow up trim of 25 degrees means 2 kgcm2 smaller counterpressure in MBT 5 than MBT 1, hence if blowing with equal air pressure you shall drain the MBT 5 sooner than MBT 1 and if not compensated, upset the trim further.
  Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Oct , 2018, 04:53
Don.
Furher to my answer above is an image showing at a bow down angle of 25 degrees you have approximately 20 kg/cm2 higher counterpressure at MBT5 than MBT1.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2018, 17:20
Hello Mr. Tore,


The reason for my question - let's say the U-Boat has just surfaced with the ballast tanks partially blown with compressed air and is in the RFO configuration:
1. Now we completely blow MBT 1 with exhaust.


An enemy aircraft is spotted and the U-Boat must dive at once:
2. We vent MBT 3 and MBT 5 (just like a normal diving process)
3. Once the U-Boat's bow and bridge spray deflector are at the surface level
4. Then they vent MBT 1


Now the U-Boat can escape the enemy aircraft with the emergency procedure. However, if MBT 1 was partially flooded when the enemy aircraft were spotted:
5. Would the partially flooded MBT 1 cause any delay when attempting to reach the proper diving angle?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Oct , 2018, 01:17
Don.
If you are surfacing in hostile waters with enemy air superiority you have to be prepared for a crashdive any time. I guess there are two different theories here, the RN WW2 procedure would be to use the empty Q tanks at the crashdive, whereas  the germans probably would surface with the Untertriebcelle (Q) filled. I don`t think the partially filled MBT 1 would delay the diving in case you are considering using dynamic force (propellers) as long as the propellers are properly submersed. Again the exhaustblowing is the final touch of the surfacing and is carried out to maintain the proper surface trim for cruising on the surface.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Nov , 2018, 00:13
Hello Mr. Tore and All,


I just applied for the LLC with a Registering Agent for the State of Georgia (total cost $189.00) and that will take about 15 days before "Kristallklar Publishing, LLC" will become an official publishing company. After that project is completed, I will apply for a US Copyright ($55.00) for "Skizzenbuch: U-Boat Type VII C Project", I'm not sure as to how long the US Copyright process will take. Then I plan on initially permitting a free download of the PDF file on this AMP website (If that is acceptable) and the Subcommittee website for their members only. Perhaps other websites later - I'm not sure at this time.


I have copy protected the PDF file with a unique password run through a four (4) rotor German Naval Enigma Machine Simulator generating the encryption for the file permissions, but as most internet users are aware; any PDF security can be hacked. However, one must consider that Skizzenbuch will have US Copyright protection as any published book and is entitled to the same copyright enforcement. I'm not worried about someone giving a copy of the Skizzenbuch PDF to a friend. However, the only protection that I am looking for is that nothing is modified without mine and my contributor's permission/control.


I will keep all informed about my progress with the Skizzenbuch distribution...


Regards,
Don_

Note: In addition, there will be a folder named "Wallet" (not copy protected) which contains eight large drawings that are referenced in Skizzenbuch.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2018, 02:27
Don.
Wonderful news, I must admit I am not very conversant as to the copyright business and cannot comment same, but am sure you take the proper steps to protect the Skizzenbuch. it contains a lot of work and it is too bad you shall have extra costs in addition to all the sweat and toil. I am looking forward to the final product and wish you all the best. The Skizzenbuch would be better than any manuals we had available when taking over the U- 995. Good luck!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 16 Nov , 2018, 11:47
Hi Don,

Thanks for the update on your Skizzenbuch. Just let us know how can we can be of assistance and we'll help.

Cheers,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2018, 00:59
Hello Mr. Tore and All,


I just got my "Kristallklar Publishing, LLC" from the State of Georgia, and I have applied for a US Copyright for "Skizzenbuch: U-Boat Type VII C Project"... After the copyright is processed and I get an ISBN number I will update the Publisher page and place a downloadable PDF file on the AMP website and on the Subcommittee website for distribution.


Well over a year ago. I started compiling information and data on the U-Boat Type IX C and the C40. I guess that will be my next project. I have gotten early-on information about the proper arrangement of a book from Dougie Martindale, so that will be one of the guiding factors in the next Skizzenbuch.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2018, 01:45
Don.
You are an inveterate enthusiast starting a new giant project after your Skizzenbuch. I wish you all the luck with your new project.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2018, 08:44
Hello Mr. Tore,


I will most likely be asking you to review the type IX mechanical schematics and my analysis of how things work. It's always good to have a 2nd opinion! Simon is going to visit U-505 at the Chicago Museum of Science and industry, Technical Museum U-995 at Laboe, the U-Boot-Museum in Cuxhaven, and the Technical Museum U-Boat Wilhelm Bauer (U-2540) this winter along with Mark Hessburg. I wish I could have tagged along, but the Sunroom and the LLC/Copyright just drained all of my of funds for next year...


I hope Simon has much better luck going to Chicago than we had in 2009 and also when touring U-505 at the museum. When Maureen and I visited U-505 they would not allow any interior photos to be taken on the interior guided tour; the tour moved too quick and the lighting was very dim so you could not see much to begin with (It really sucked). I could only get exterior photos of U-505... That was a waist of money and a three and trip to Chicago got messed-up by a 1 day weather delay at the very beginning - hung at the Atlanta Hartsfield Jackson International Airport over night - then hotel reservation at the Chicago Hyatt wouldn't allow us to stay for the 3rd day - so we had to find another hotel for the scheduled 3 day trip. To add insult to injury, all Delta flights were full on the last day because our reservation was for the previous day, so we had to find another airlines (American) to get back home.


I HATE AIRLINES because when things go very wrong their passengers/customers are on your own and they assume no responsibility (Everything is an act of God), and you have to fight to get your money back from the cancelled/missed flight!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2018, 10:08
Don.
I have briefly looked at the IXC which is, apart from a few exceptions, based on the same technique as the VIIC s and  I shall be happy to participate in the coming IXC discussions for your next Skizzenbuch.  To be quite frank, I planned a few years back to visit the old U 995 with my grandchildren, but as I saw the images of my old lady I lost the interest as too much was changed since my time, she has definitely become a museum piece.
I was for a few years in charge as manufacturer inspector of the engines of the two passenger ferries m/s Kronprins Harald and m/s Prinsesse Ragnhild operating on the Kiel - Oslo service and passed Laboe and U 995 many times. I was always up at the bridge looking at her sitting high and dry on her concrete cradle, for some reason I still wasn`t tempted to visit her.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Dec , 2018, 01:37
Hello Mr. Tore and All,


I applied for the copyright for "Skizzenbuch: U-Boat Type VII C Project" to the US Library of Congress on December 4, 2018, and this process takes about three (3) month for completion. Then I will make the final update to Skizzenbuch and then it will be available to U-Boat enthusiasts. This has been a long and tedious process for me, but I can see where things are coming together.


Regards,
Don_


FYI....
Copyright Author Credits:
Donald M. Prince - Managing Editor/Contributor
Tore Berg-Nielsen - Contributor
Maciek Florek (Deceased) - Contributor
Simon J. Morris - Contributor
Mark Hessburg - Contributor
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Dec , 2018, 03:25
Don
Great news, looking forward to seeing the "Skizzenbuch" early spring next year.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Dec , 2018, 01:25
Hello Mr. Tore and All...
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Dec , 2018, 06:46
Don and all others
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jan , 2019, 09:14
Happy New Year!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jan , 2019, 11:42
Hello Mr. Tore,


Nice touch with the added Orca - Killer Whales to the painting....  Here's hoping we all have a good 2019 New Year!


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jan , 2019, 02:59
Hello Mr. Tore,


I was talking with my wife Maureen... She uses WhatsApp to chat and talk with her friends and relatives in Asia and there is no cost for the phone service. Maureen has an iPhone 10 with a facing camera and she and some of her relatives have video calls. Do you have a smart phone with WhatsApp? It would be interesting...


Regards,
Don_ 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2019, 04:42
Sorry Don I dont think my smartphone works as an iPhone I shall consult my grandchildren and revert if I have a possibility.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jan , 2019, 19:05
If you have a smartphone, then all you need to do is have your grandchildren to download WhatsApp and install it...
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2019, 23:08
Don. I have invited my grandchildren for dinner coming Sunday in February.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: 42rocker on 10 Jan , 2019, 07:11
Looking forward to seeing the pdf happen. May things continue to go well with it. Thanks to Everyone. 
 
Later Tim
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jan , 2019, 19:42
I should get the US Library of Congress copyright in February or Early March. Then It will take a few minutes to update Skizzenbuch and make it available.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 10 Jan , 2019, 23:12
I can not wait....
Thanks in advance for the great gift you will make to the membres of this forum and to all U-Boats enthusiasts all over the world...
Regards.
Filippo
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 28 Jan , 2019, 23:31
Hi Don,
nerws about Skizzenbuck copyright ?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jan , 2019, 01:02
Hi Filippo,


I applied for the Copyright on December 4, 2018 and their website states that an electronic application takes about 3 months. So perhaps in early March; if the US Government shutdown doesn't add some additional time delay???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 28 Feb , 2019, 23:56
Hi Don,[/size]news about Skizzenbuck copyright ?[/color]
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Mar , 2019, 02:29
Hello Filippo,


You have been very persistent and patient, but I can not rush the US Federal Copyright Service to get things done faster... If you will send me an email "donprince5207@comcast.net" stating that you will not distribute the non-copyright version of Skizzenbuch, then I will send you a link to my dropbox website Skizzenbuch folder and you may download the "Skizzenbuch 11 x 17 - M + I.PDF" file and the accompanying "Wallet" folder containing nine (9) large drawings. Once the Copyright version is available, then you must delete the non-copyright version because I may still be making any needed corrections.


PS: Let me know what you think of our four (4) year collaborative Skizzenbuch: U-Boat Type VII C Project...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Anakin on 01 Mar , 2019, 15:11
Credits for all of you guys for making this possible. I will be waiting it to be released for purchasing.  ;)
regards,Antti
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Mar , 2019, 19:32
"Skizzenbuch: U-Boat Type VII C Project" is a semi-technical and highly graphical 516 page PDF book in an 11 x 17 inch format accompanied by a Wallet folder with 10 large drawings. At this time, my intentions are to make it available/downloadable on several U-Boat websites for free...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 03 Mar , 2019, 05:01
Thanks Don, Tore et all.
We are very much looking forward to its release.
Cheers
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: 42rocker on 03 Mar , 2019, 06:44
Wow, how nice. Thanks Don. And all who helped. 
 
Later Tim
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 03 Mar , 2019, 23:44
Thanks Don,
I think that Skizzenbuch will be a fantastic gift for all U-Boat modelers and in general for all U-Boat enthusiasts....
Respect
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Mar , 2019, 18:14
Hello Mr. Tore and All,


I have uploaded a new version of Skizzenbuch 11 x 17 - M + Ie.PDF... I have made a few changes to pages 456 through 461 to make the active and passive detection systems less confusing (I hope)! I sure do miss Maciek's help on this subject...


I should not have a problem with the copyright because they state minor changes/corrections may be made to the released document/book.


Regards,
Don_


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 20 Mar , 2019, 17:59
Hi Tore

While on U-995, I was able to find the original Lubricating Oil cooling under the flooring. In fact, it look like most of the original piping is still under the new floor  :)

(https://farm8.staticflickr.com/7849/33554782018_e90e0aa5b9_o.jpg)

(https://farm8.staticflickr.com/7853/40465033593_faa24a3c77_o.jpg)


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Mar , 2019, 02:22
Hi Simon.
Nice images and I guess the cooler is not far from your final drawing. The gatevalve shown on the lower image is possibly one of the three gatevalves in the coolingwatercrossover pipe. Wish I could have join you on the visit.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2019, 20:15
Hi Simon,


Great photos... Would you agree with my labeling on the photos?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2019, 21:21

(https://farm8.staticflickr.com/7897/40473080383_0edca000ae_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2019, 21:24
2nd photo
pipe in foreground is P14/16
I believe the pipe is P14/11, and not the Lubricating Oil filter.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 21 Mar , 2019, 21:37
The two control arms are P14/20

(https://farm8.staticflickr.com/7899/47439041931_5503a13e3a_o.jpg)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Mar , 2019, 22:53
Hi Simon,


Circled in yellow - lube oil knife type filter?


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 22 Mar , 2019, 01:28
Hi Simon,


Circled in yellow - lube oil knife type filter?


Don_
It does look like a  lube oil knife type filter. But it seen that one pipe is going forward and the other is going aft ??? We need to check with Tore.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Mar , 2019, 07:43
Don
I guess the assumed knifefilter is one of  three gatevalves in the crossover coolingwaterpipe. The crossoverpipe has alltogether 5 gatevalves of which the three amidship have wheelstem extension to the floorplates. The lubeoil filters are situated closer to the engines and as you know were fitted on the later VIICs only, as a substitute for the lubeoil sentrifuges which were removed due to space and weight requirement. Below two images showing the coolingwatersystem and the construction of the gatevalve. On the plate 13 you`ll see the icons of a "Schieber", german for gatevalve in the coolingwater crossoverpipe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Mar , 2019, 22:18
Hello Mr. Tore,


Thanks for clarifying about the cooling water gate valves posted earlier... Simon got some great photos below the deck of U-995.  I wonder how he did it! Mark also got some excellent interior and exterior photos and answered some questions I had about the remaining RADAR equipment...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Apr , 2019, 03:18
Don and others interested.


A few years back Maciek introduced me to an US author Larry Simpson who was looking for a technical consultant on German Uboats like VIICs and IXCs. I volunteered on a non paid basis, but after Maciek passed  away I became the only technical consultant to the writer. Larry Simpson wrote a fiction book of a German WW2 submarine deploying a weather station in Alaska. We decided to choose a IXC /40type and used the U 807, a boat having keel laid down in 1943 but never commissioned. We worked on the book for about two years and in these days it is published on Amazon. The title is Cold Refuge by Larry Simpson. Larry let the Chief engineer explain the technical details related to the uboat and as he was`t fully conversant with the law of Archimedes he, with my consent, introduced me as the chief of the U 807 explaining the details. If you have a Kindle you might get a copy at Amazon for a very reasonable price. I guess the book is interesting as the story of the Uboat weather stations are not widely known.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 07 Apr , 2019, 04:22

Quote
Don and others interested.[/size]A few years back Maciek introduced me to an US author Larry Simpson who was looking for a technical consultant on German Uboats like VIICs and IXCs. I volunteered on a non paid basis, but after Maciek passed  away I became the only technical consultant to the writer. Larry Simpson wrote a fiction book of a German WW2 submarine deploying a weather station in Alaska. We decided to choose a IXC /40type and used the U 807, a boat having keel laid down in 1943 but never commissioned. We worked on the book for about two years and in these days it is published on Amazon. The title is Cold Refuge by Larry Simpson. Larry let the Chief engineer explain the technical details related to the uboat and as he was`t fully conversant with the law of Archimedes he, with my consent, introduced me as the chief of the U 807 explaining the details. If you have a Kindle you might get a copy at Amazon for a very reasonable price. I guess the book is interesting as the story of the Uboat weather stations are not widely known.Tore[/color]


I just ordered the book as paperback.
I am old school when it comes to books.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 08 Apr , 2019, 09:29
I'll try to get a copy asap, thank you for letting us know Tore!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 May , 2019, 00:52
Hello All,


I found it again on how to stay logged in on this website...


1. Click on a link you use to get to this website
2. Click on someones name above their avatar
3. Type in your user ID and Password (No Enter)
4. Then you see a 90 minutes, and a forever box
5. Check the forever box and now hit Enter.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2019, 12:08

Katuna.
Posting a cross section drawing of the GW direct reversible diesel engine as executed for the 1942 VIICs. If you want to go into details just mark off which detail interest you like on the images below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jun , 2019, 14:01
Katuna.
The torsional vibration damper is situated on the front of the crankshaft in the round casing.  The purpose of the damper is, as you have variable masses clutched in and out in the shaft system, like propellers, clutches, generators, and motors you create a complex system with high variable torsional vibrations  building up stresses in the crankshafts which sometimes even can break the shaft, this damper prevent that. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 08 Jun , 2019, 10:42
Is this the pump you are referring to? I thought this was original as I thought it was the Auxiliary Oil Pump. It shows up on Plate 9 of the detail drawings.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2019, 12:28
Katuna.
The horizontal pump is far too small for an aux. luboil pump. The aux luboilpump is a very versatile vertical big pump as shown with a red arrow on the image below. The aux. luboilpump is used both as a fueltransferpump and as an aux. luboil pump for both port and stb main engines. Below is an attemp to indicate the various alternatives Further the aux luboil pump is used to created luboilpressure when turning the engine by air or cranking like during maintenance and if the engine is flooded. Feel free to ask questions if any.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2019, 12:36
Katuna
I almost forgot, if you intend to go into details of the engineroom, try to start with a main engine having the right pipeconnections as quite a part of the pipelinesystems are intergrated with the engine pipings.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 08 Jun , 2019, 13:30
Engineering Tools and Spares.


Mr Tore.
From your memory I was wondering what general maintenance tools were carried onboard and where were they stored?
Obviously space was a premium so small hand tools spanners, hammers, hack saws etc in toolboxes? Stored where? Compartments in Engine room?
Was there also any small fold away workbenches with vices etc?
Did you carry any specialist tools for any larger repairs when too far away from port.?
Welding equipment etc?


Also did you carry spares or in peacetime was it easier to return or be towed back to port?


I know U505 carried spare Pistons but that was essential in Wartime. Maybe not required in peacetime?


Appreciate your insights. Thanks

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 08 Jun , 2019, 14:10

Raymic - I'm curious about the stowage of tools and spares as well. Depending on which line drawings you look at, it appears there is a "tool room" located just forward of the ammo storage under the officers quarters. I've wondered if this is time period specific as it shows on some Type VII drawings but not all.


I also came across info about shoring timbers. They were stored in the Forward Torpedo room and the Engine Room. Where in the heck would they have room to store timbers
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Jun , 2019, 14:35


Yes we carried tools and spares like piston and liner, Pistonrings, HP fuelpumps and nozzles, main bearingshells and crankpin bearingshells. The parts were stored in containers and sometimes strapped wherever we could find place towards the shipside. As our operational area was mostly along the coast we use the coastal shipyards for major works. A common, but pretty cramped storage place was strapping parts between the main engines and shipside. I particulary remember a piston stored in a container filled with oil which I was checking, I was opening the lid and stuck my hand into the container, the oil made my fingers slippery and my marriage ring slipped off and down to the container bottom, we had a hell of a job to recover the ring. Otherwise there was no special cabinet or storage space for tools. The tool room indicated by you was for weapons as far as I remember. Wooden beams etc were scares, we could get same from shore and similar large items were stored in the casing duly secured. Otherwise we used the pressuretight casing deckcontainers, they were excellent for potatoes. Otherwise on mission above the artic circle we were accompanied by a submarine tender have a proper workshop for able to service several submarines.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 08 Jun , 2019, 15:26
Fascinating thanks Tore.
I'm sure Mrs Tore wouldn't have been happy with you losing your ring....


Katuna
That Tool area you refer to is accessed through the munitions room side wall (which has its own floor hatch) and/or possibly by its own floor hatch. but it is for the electronics sounding/radio  gear below the sailors operating area.
I've never seen a photo but read about it in one of my many books. Ill see if I can find more when time.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2019, 00:32
Raymic.

I was newly married in those days so it would give me big troubles coming home without a ring. In the wardroom we had several hatches giving access to the munition room, weapons etc. One of the frequent used hatch was the fore battery compartment floor hatch visited by the chief electrician every morning and evening because of monotoring the charging condition of the batteries by checking the acid weights. The figures were noted on a blackboard next to my bunk, updating me and my fellow officers, we always checked the blackboard, the acid weight was just as important as the weather.
Tore     
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 09 Jun , 2019, 01:23
Thanks Tore. I'm an Electrician and now Electrical Engineer so that's very interesting.
Day to day possibly mundane at the time operations of a Uboat are very interesting from a historical perspective.
Please share anything like that.


Here's my model in progress of the Ward room area.
I put 4 hatches in the floor from reference drawings.
The first I've opened up and goes to the armaments. The next goes to the 'Tool' room Katuna mentioned.
The 3rd and 4th would go to the batteries I think.
Cheers




Ps. Any info on what certain cupboards and what's behind hatches and closed doors is always interesting.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2019, 01:31
Katuna.
Your image from das Boot seems to be pretty close to the real thing, except the not painted parts like the push rods are a bit too rusty. The engineroom crew of a submarine does not differ from normal engine room crew, on boring long watches they spend a lot of time shining the engines, using emery paper and polishpaste. Brass and steel were shining and not painted. It is unfortunate that the old U 995 has blue painted pushrods, red painted brass manometers and gauges, even red nuts, handles and pipes. In spite of warnings the model builders, even kitmakers copy this which sometimes make the VIIC models look like they were an item of an amusementpark.  Generally there is a tendency to overdue the weathering, corrosion, the wear and tear of a VIIC model both externally and gloomy internally. The lifetime of a WW2 VIIC was fairly short, don`t make your model like a heap of rust ready for the scrapyard.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jun , 2019, 03:20
Katuna.

Below I have tried to indicate the details of the wardroom. COs cabin is obvious. The wardroom had two bunks on the starboard side. Towards  the ship side were  the bunks. The lower bunk is for the chief engineer and the upper bunk for no 1. My "office" was the cupboard towards aft, the cupboard contained drawings , logbooks and papers related to my job and I had a small plate fixed to the cupboard wall as a writing desk, towards the wardrom was the blackboard for the acid weight. The typewriter I borrowed from the radio operator as did the CO. The wardobes and lockers were kind of humide and our stripes got green, so quite against the rules I asked the chief electrician to install one of those coalfiber bulbs in my wardrobe closet and lockers to keep it dry. This worked but was exclusively for me, even the CO didn`t get it. I don`t know if other copied my idea. On the port side of the wardroom are the bunks and lockers for the junior officers. As the wardroom was normally used as dining and dayroom, the poor guys used hot bunks. With some minor trouble you could ease down on the lower bunk using same as a seat at the table when somebody slept in the upper bunk.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 11 Jun , 2019, 14:55
Tore - Is there any tank located under the pumps and piping forward of the engines or is it just open bilge? In the line drawing below it shows a Fuel Oil collection tank spanning from Port to Stbd. On Simon's 3D rendering there is no tank there. I realize that Simon may have purposely left that out to clarify the piping detail. Curious as I'm beginning to move that direction.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2019, 01:09
Katuna. I guess you can trust Simons drawing, I can`t remember any other tank in this area. However the draintank is a part of the fuel venting and draining system of the engines which all ends up in the draintank. This is an intricate system of very small pipes on the engine and I guess more or less impossible to copy on this scale. Nevertheless the system is important as it is designed to prevent fuel pollution of the bilges. Below a small part of the fuel daytank, supply and drainage system, if you want to go into the system just ask.

Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2019, 01:42
Katuna

Another GA plan showing the fueldrain tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 12 Jun , 2019, 07:52
Oddly, the Trumpeter kit actually has that piping. Some of the few pipes they actually molded. This is a pic from another builder but it shows those drains, albeit a little overscale. That's easy enough to recreate in brass wire.

What is the actual purpose of the FO gravity tank?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 12 Jun , 2019, 09:10
Another question, is the pipe in Simon's drawing shown running through the center tanks the same as in the plate drawing?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2019, 10:42
Oddly, the Trumpeter kit actually has that piping. Some of the few pipes they actually molded. This is a pic from another builder but it shows those drains, albeit a little overscale. That's easy enough to recreate in brass wire.

What is the actual purpose of the FO gravity tank?
Katuna

As you probably know the fuelsystem of the VIICs are seawatercompensated which means the fueltanks are always full, having fuel on the top, eleminating the possible trim trouble and free surface effect. As the fuel is consumed the tanks are topped up by the seawatercompensating system which    takes its seawater from the main engine coolingwater at the exhaustsilencer watercooling and pumped up to a head  tank in the towercasing, by that the system is always under the correct pressure. From the head tank the water enter the relevant fueloiltank and fuel on the top of the tank can be transfered to the fuelsystem of the engine. The fuel system on the engine consist of a double day gravetytank (settlingtank) one half connected to the engines at the time. The tank not connected to the engines is topped up by the compensatingsystem, the other half to the engine driven fuelsupplypump attached to the engine. As the system sketch shows a MAN engine having the fuelsupply pump at the aft end I have drawn the supply pipe to the front of the GW engine. The fuelsupply pump supplies fuel under low pressure to the HP fuelpump for each cylinders. The system for suppling fuel to and from the daytank has a meter dial for the consumption and a special cock for easy selection of tanks. Just ask if any question.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2019, 11:42
Katuna.
I might be I misunderstodd you question on the pipeline you show on the systemsketch plate 9. It shows indeed the main coolingpipe to aft, compressores, Emotors, Thrustbearing etc. But the pipe you refer to is probably the main bilge drainpipe which goes to the suction side of the main bilge pump in the controlroom, thus two different pipes. See image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 12 Jun , 2019, 11:47
Ok, I didn't notice the bilge pick up screen was attached to that pipe. Does that bilge pipe run the length of the boat? I believe the bilge pump is in the Control room, correct?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jun , 2019, 13:48
Katuna.
Yes the main bilgedrain pipesystem goes to every compartment in the boat. You are able to open the footvalve of the adjacent compartment by extended valvestem/rods through the watertight bulkhead as shown below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 12 Jun , 2019, 14:53
Thanks for the bilge info.


Ok, next question, what is this shield that is outboard of both engines? Depending on which drawing you look at, it either angles down or it had a compound curve that angles back upwards. Is this some sort of sheetmetal shield or bracing? Looking at the drawings it is difficult to decipher what it is exactly.


In Simon's drawing it is clearer from overhead but it isn't clear which direction it goes or what material it is made from. To me it looks like it curves down from the engine bed rail to the frame ribs.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2019, 02:57
Katuna.

I assume you refer to the two black rectangles between the frames towards bord and the engine. Below is Simons drawing of the dieselair system. As the dieselengines are fairly large they need a lot of air for combustion. This air would create a substansial draft through the submarines compartments hence you need a separate diesel air supply shaft outside the pressurehull as drawn by Simon. Although the dieselair shaft main inlet valve is situated in the tower casing, the intake is susceptible to water during heavy sea and the airduct gets partly filled with seawater. Just after the main intake hullvalve for the dieselair ( in the engineroom) the circular air duct is split in two, and transferred into rectangular sheet metal ducts, port and starboard, which fits between the frames towards the pressurehull , the ducts ends up halfway from the bilges. Hence the seawater ends into the bilge and the mainengine air intakes are safely from the water. During heavy weather it was fascinating to see how much water was gushing into the bilge where it could be handled by the bilge pump in the controlroom.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 13 Jun , 2019, 08:45
This is the plate I'm speaking of. It appears to go under the starting air tank and over the oxygen tank.


I was unaware there was a duct from the Induction valve to the intakes.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2019, 11:25
Katuna.
What you refer to is the mainengine foundation steelbed in the engineroom which is a very thick steelplate where the mainengine is adjusted and fixed by bolts and nuts. The foundation has of course to be very stable and rigidly connected to the hull. Simons drawing shows the top bedplate which has to be accurately placed for correct adjustment of the mainengine bedplate. The foundation plate is slightly elevated and outside the engine contact surface bended and tapered down to the frames where it is fixed by welding for an extra rigid and stable connection to the hull. See image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 13 Jun , 2019, 12:04

Ok, that's what I thought but could never verify with a clear end view.


I see now the air intake duct. So if I understand correctly, the duct ran below that stabilizing plate and the plate acted as a diffuser or baffle to allow sea water to drop out into the bilge and air was pulled up into the intake through the spacings in the plate?


Then this would be the induction duct, correct?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2019, 14:03
Katuna.
Yes you found the the main dieselair inletvalve and the rectangular duct to each of the engines. I don`t think the downfolded topplate for the mainengine bedplate plays a role in the dieselair ducts, they are mainly a strenghtening element in the engine foundation. Apart from delivering air to the engines the ducts are draining the seawater freely to the bilges. As to the diesel air shaft going from the main inletvalve in the towercasing to the main hullvalve at the engineroom it add a fairly large enclosed airvolume to displacement when submerged. We once had an unpleasant issue after a refit during some testdives in a deep fjord. Somehow the dieselair mainvalve in the tower didn`t shut properly and the diesel air shaft gradually got filled with seawater. We just dropped down like an elevator and at some 50 meter we blew all the ballast tanks and everybody were staring at the depthgauge  which just kept moving until it slowed down and finally the needle pointed at some 125meter before the submarine stopped and very slowly started to ascend. Then she accelerated towards the surface as the air in the ballasttanks expanded and the  ex U 995 broke the surface like a spectacular rocket, a highly irregular (and dangerous) surfacing. She had some damages in MBT 3 and we had not had a deep testdive since then, which caused some excitement.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 13 Jun , 2019, 15:13

Wow! That is the kind of experience that makes for a great story after the fact but not at the time. Just like out of a Hollywood movie. Not a pleasant experience at the time I'm sure. Thank you for sharing that with us.


Do those ducts just curve downward between the frames and then abruptly end at a certain point? I see now in some of the drawings and some photos of U-995 how the duct goes across the top and turns downwards but you cannot tell how or where it ends.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2019, 00:46
Hello Mr. Tore,


I remember where U-926 had some MBT3 damage issues and that was the reason she was left for the Norwegians because she was deemed unfit for sea duty. Could that have been the cause of the MBT3 damage to U-926 where the diesel air main external valve under the tower failed to shut? Otherwise, I believe they could have sabotaged U-926 by blowing MBT3 and running at depth with the dive planes down until the Kingstons were shut, and then rising. That would damage MBT3 and make U-926 unfit for the enemy to use after the war ended...

I know, I have a devious mind...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2019, 01:57
Don.
You are correct in you memory about U-926 avoiding operation searchlight. I guess the investigation revealed that possibly the germans had blown MBT with shut Kingstons. At the end of the war it was difficult to get skilled submarine crew and opening and shutting of the Kingstons was not a daily event as you had to use special cranks. It could have happen by accident during moving the submarine. If I remember correctly the testpressure of MBT 3 was only 30 m H2O. I have also heard that she probably had open Kingstons during an allied air attack on the submarine pen in Bergen. Anyhow she did a firstclass service as a NATO submarine in the 50ties.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2019, 02:02
Katuna.
I guess the tapered steelplate lips for the engine bedplate ends towards the frames where they are fixed by welding.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2019, 02:11
To all your guys following my thread, I shall leave for my farm in remote wilderness with bad internet connections hence my activity shall be reduced for a couple of days. Back on monday.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2019, 03:07
Hello Mr. Tore,


Be very careful with the drive to the farm... NO repeats of last year!


I have remarked the drawing... Does it look OK.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2019, 03:24
Don.
My son in law is driving hopefully we arrive safely and no repeat of last year. I shall revert with further comments over the week end. Is Simon around or is he still chasing the snow?, I guess he did a lot of research before making the drawing. Back on monday.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jun , 2019, 10:12
Hello Mr. Tore and Katuna,


It's Winter season down under in New Zealand, so I guess Simon is busy at work studying avalanches and working on his advanced degree!


Good discussion... This subject was not covered before in such great detail. It looks like the air induction box is extended on both sides with sheet metal plating and screwed to frames 25 and 26 (My best guess). That way in rough seas where water enters the diesel air intake stack below the bridge, it will be dumped into the Bilge to the drain structures previously discussed.


I believe the Diesel engine running aspirated or supercharged will draw the air from the air induction plenum. Does this sound about right?


Drawings attached,


Regards,
Don_   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jun , 2019, 11:04
Hello Mr. Tore,


Looking at one of Simon's drawings makes the drainage and engine block support look entirely different. The lighter structure seems to attach to the frames and the engine block to form the support for the Diesel engine room.  Also, I believe the dark area between the frames to the right is indicating the frames where the air induction plenum is located above. What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2019, 14:06
Don.


I guess it would make it easier not to combine the bedplate structure and the diesel airshaft, they really don`t relate to each other as the diesel  air shaft ends far away from the diesel engine air intakes. The combustion air of the diesel is either normal aspirated or supercharged. When the engine is in normal aspirated air mode, air is drawn in via a rotary inletvalve into an airmanifold alongside the engine, from this manifold are separate ducts to the inletvalves on each cylinderhead. When the engines are running supercharged you clutch in the Roots blower, at the same time you rotates shut the aspirated air manifold inlet valves, as the roots blower discharge is directly connected to the aspirated air inlet manifold, the manifold is now becoming supercharged airmanifold.  As all the air inlets are far away from the outlet of the dieselair shaft the drain of the shaft do not interfere.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2019, 14:28
Don

The topplate for the mainengine bedplate is a very thick steelplate on which the main engine bedplate is bolted and adjusted by shims. The plate is drawn on the image below and outside the landing area of the engine bedplate, bent down and welded to the pressurehullstructure (frames) for a very rigid connection to the pressurehull. The ligth blue-greenish coloured area are open surfaces and the light grey area the topplate extended down to the pressurehull frames.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jun , 2019, 21:31
Hello Mr. Tore and all,


I updated Skizzenbuch pages 239 (images), 240 (text and images), 350 (image) and 351 (images). I placed the latest version of Skizzenbuch in Dropbox...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 18 Jun , 2019, 12:17
Tore - I noticed these baskets in the Engine Room and another in the Control Room. Were these original to the boat or added post-war?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Jun , 2019, 13:41

Katuna.
These were indeed "baskets" for storage which we used for spares and tools. I guess during the WW2 they were used for, provisions as well it was seldom needed  for foodstorage in my time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 18 Jun , 2019, 13:47
Ok, that was my guess. I just wasn't sure if those were wartime or post. Thanks!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 18 Jun , 2019, 15:13
Here's another one for you; Is this the clutch actuating arm? I was looking at a build on another site and noticed this mechanism. If not the clutch arm, then...?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Jun , 2019, 16:08
Hello Katuna,


Skizzenbuch page 267 brackets above valves in the control room...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Jun , 2019, 16:17
Hello Katuna,


Main Clutch hydraulics in Skizzenbuch on page 425...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Jun , 2019, 01:02
Katuna


I guess the Trumpeter kit has missed a few details with regards to the main clutch. The clutch arm is over dimensioned and the lowerpart is cut off. The system is pneumatic-hydraulic operation of a lever connected on the top to a piston having adjustable pistonrod with two guides having end stoppers, the lever is double and split around the propellershaft having a carrierring connected to the operating link on the clutch. As the main lever is moved by the pneumatic-hydraulic system it moves the carrierring and hence the operating link on the clutch. As the system shall not function unless there is a fulcrum at the lower end of the lever you have to extend the pneumatic-hydraulic operated lever down and fit a fulcrum on the bulkhead aft on the dirtyoil tank to get it correct. Don has posted a sketch showing the system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 19 Jun , 2019, 04:07
So much fantastic information in the Schizzenbuch from many years of your hard work.
Any idea when we can all get to see it? thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jun , 2019, 11:06
Hello Raymic1,


I have applied for a US Copyright back in December of 2018. According to the US Library of Congress, this process takes a maximum of nine (9) months. Once I get the US Copyright, then I will update the PDF file and make "Skizzenbuch: U-Boat Type VII C Project" available from several U-Boat websites at no cost. I will post the website list when the process is completed...


Skizzenbuch consists of 516 pages in a 11 x 17 inch format (Required so the original mechanical and electrical schematics are viewable).


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 19 Jun , 2019, 15:43

It's Winter season down under in New Zealand, so I guess Simon is busy at work studying avalanches and working on his advanced degree!


My winter work almost started as soon as I got back from my trip from visiting U-505 and U-995. Now into my three year of full-time work and research into snow and avalanches. I found it hard to do the same amount of U-boat research I did when I only worked for 6 months of the year. And I am planning to be busy for the next few years with a new laser scanner we purchase this summer at work. With this laser scanner we can scan the snow surface up to 6 km away, to 15 mm precisely, 300,000 times per minute. Would have love it while visiting U-995  ;D
 
I am still going through all the data and photos I collected while at U-995 and slowly improving the accurate of my model. I am hoping to make so big improvement to the casting and pressure hull this coming summer.
 
I never confirm the actual layout of the bedplate, but I believe the bedplate surface was a different bit of steel plate, with the bedplate supports angle down at 25 degs to the pressure hull.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 22 Jun , 2019, 13:25

Don - Thanks for the confirmation on the Refrig. Comp/Cond unit. I've been trying to nail that one down for quite some time!


Tore - And thanks to you for the clutch info. I had never seen that actuator arm before and wasn't quite sure that what I was looking at on the other modeler post. Definitely a needed detail in the foreground of the model.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 28 Jun , 2019, 15:57
Tore - Can you translate these telegraph labels. I'm going through several pages of data on U-Historia and translating several pages of info but my Google Translate Can't seem to figure most of this one out. No doubt the abbreviated words are tripping it up. Thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 28 Jun , 2019, 19:45
FYI
U-Historia has a fantastic German Uboat glossary with abbreviations and slang.
Might be helpful but I'm sure Mr Tore will know these well.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Jun , 2019, 23:26
Hello Forum Moderator...


When I enter a word with an Umlaut the letted is not displayed and everything after it is gone? I can preview it OK???


Regards,
Don
i.e. = Zur
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jun , 2019, 00:06
Tore - Can you translate these telegraph labels. I'm going through several pages of data on U-Historia and translating several pages of info but my Google Translate Can't seem to figure most of this one out. No doubt the abbreviated words are tripping it up. Thanks.


There are several execution of the engineroom telegraph. This is one of the most common. When it says both engines 10less it means 10 less revs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jun , 2019, 04:01
Hello Mr. Tore,


"Beide Maschinen 10 Weniger" - Does that apply to both Diesel and E-Motor? The word Maschinen seems to indicate E-Motor and not Diesel...


Was Emergency Speed (2 x AK) Diesels and E-Motors 480 rpm, 4/5 speed (2 x GF) Diesel 460 rpm, and 3/5 speed (2 x HF) Diesel 390 rpm audible orders only?


Were there many reasons for the reverse higher speeds when surfaced or submerged?




Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 29 Jun , 2019, 08:40
The word "Maschinen" perfectly fits for the Diesel engines too.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Jun , 2019, 09:27
Don.
The engine telegraph is an old fashion way of controlling the engine output and the wording of the orders transmitted bears evidence of that. The old marine language both in English and German did not distinguish between diesel, electric motor and steam engine, hence maschine or engine was used for the main engines in both languages generally.  In the submarine language we did make a difference between diesel and e-motor. The output and rpm (often called wrongly speed) relation of a dieselengine is following a graph put up at the testbed where the engine is connected to a waterbrake which follows the propellerlaw. The engineroom crew following the engine telegraph orders follows approximatly such a graph by adjusting the HP fuelpumps injection volume in relation to the rpm. Today this is done automatically by the governor.
Beide Maschine 10 weniger, I guess this means the propellers, regardless the powers source.

There could be situations that you would need as much power ( bollard pull) astern as possible when submerged, like sitting on the seabed and getting stuck in the clay, getting entangled in some object like u-boat net etc. In the days before schnorchel you would of course use the E-motors. On the surface likewise due to grounding, ice etc. you would need bollard pull rather than speed, anyhow the dieselengines have to give max.output or the max bollard pull, not speed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jun , 2019, 14:05
Hello Mr. Tore and All,


Thanks for the info about the telegraph gauge... I updated Skizzenbuck pages 416 and 417 to include this info and the new version is in dropbox. I asked the US Copyright office about Skizzenbuch and that have assigned an expeditor to the project and I am looking forward to receive the certificate very soon. It has been almost 7 months since I electronically applied for the copyright. They state on their Website that the electronic expected time period is 4 to 7 months for an application completion. I can make minor revisions or corrections without the need for a new application...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 29 Jun , 2019, 16:46
U995 Floor Covering


Mr Tore
Apologies if this has been asked before but it is quite difficult to find previous threads still with pictures that work.


The U995 modern day museum shows just metal tread plate flooring in most rooms.
As that must have been quite loud with men walking and running  (Soanar hazard) I'm trying to determine if during WW2 they would have had some sort of acoustic rubber matting etc?


I have seen some WW2 pictures of the crew lifting rubber matting up to access tread plate hatches (CO area Ammo store) on some Uboats but it doesn't seem to be a consistent use of rubber matting across all pictures.


Your thoughts?
Was a rubber matting covering on U995 post war but removed to be a Museum?


thanks
Raymic
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2019, 02:11
Raymic.

Unfortuately the Laboe U 995`s flooring  is renewed to fit the visitors safety and wear. Below are a few floor plating images from my time. Basicly in the crews quarter the flooring was linoleum plates duly secured and brownish in colour. In the controlroom, E-room and dieselroom, steelplates. As far as I remember we had some fibermats in the areas near the tower ladder and the access hatches in the two spherical bulkheads at each end of the controlroom. These mats were put in these spots more for the internal noise. In the engine room we used fibermats for maintenance works to prevent damage to the parts dismantled or fitted. When the order silent running was given, we some times took of shoes, stopped non essential noisy machinery etc. In general in the daily sailing when the diesels were running we didn`t care about the noise only when the order silent running was given.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jun , 2019, 04:04
Hello Mr. Tore,


Were the tables in the forward torpedo room the only tables with the wing nuts to secure the tables? They had to remove the tables in order to get to the torpedoes stored below deck. Also, where did they store the tables when accessing the torpedoes below deck?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2019, 04:13
Don.
As far as I remember, yes, and you are right about the torpedostorage I guess the tables were stored towards the pressurehull, I don`t remember for sure..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2019, 22:00
Hello Mr. Tore,


Were the tables with the wing nuts photo taken from U-995 of U-926 when you were the EO?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2019, 00:22
Don.
I don`t think they were, down below I have superimposed the tables on Falos present days forw. torpedoroom image of U 995 at Laboe.
Tore
Hello Mr. Tore,


Were the tables with the wing nuts photo taken from U-995 of U-926 when you were the EO?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2019, 00:35
Hello Mr. Tore,


Is this photo real or a doctored image? What U-Boat?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2019, 00:57
Don.
Sorry I photoshopped the tables into Falos image from the museum U 995. I have no image of the wingnut from KNM Kaura ex U 996.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2019, 01:14
Hello Mr. Tore,


Can you post the image of the tables?
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2019, 01:31
Don. I `m not sure which image you mean, down below is Falos image of the tables on U-995 today and a separate one from an unknown VIIC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2019, 14:52
Hello Mr. Tore and All,


I have updated Page 297 with info about the tables in the Torpedo room, and changed a photo on page 225 because it was incorrect. The updated Skizzenbuch PDF has been uploaded into Dropbox.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 03 Jul , 2019, 14:56

Don - I'm unfamiliar with Dropbox. How can we partake?

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jul , 2019, 20:43
Hello Katuna,


I have open links for people that have helped me create "Skizzenbuch: U-Boat Type VII C Project" which is a book in an 11 x 17 inch format with well over 536 pages of text and images. It includes the Original German WWII U-Boat mechanical and electrical schematics with our attempt to provide a readable textual explanation in detail. I have applied for a US Copyright under my name and those that have contributed to the book and I believe I will get the certificate sometime this month. Once the copyright is approved, then I will make Skizzenbuch available to all at no cost through several websites...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 04 Jul , 2019, 14:19
Cant wait!!! Thanks Don, Tore et all.......
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 05 Jul , 2019, 16:16

Tore - Care to have a go at a translation of this Battery Switch data plate? Google can't figure it out. I think it has something to do with foreign voltage but I can't decipher it.


Thanks!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2019, 20:23
Hello Katuna,


My best guess:


When charging the battery in series from an external circuit where + pole Port and - pole Starboard on the main switchboard (together) design/connection.


Battery main-switch 1


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2019, 01:34
Katuna.
As you probably know the two battery groups are separated in two compartments no 1 battery right in front of the engineroom and no2 fore of the controlroom. These two battery groups can be coupled to the main switchboard by the automatic circuitbreaker ( overload current 5000 amps. in 6 seconds ) where the batteri groups can be switched either in series or parallel depending upon the voltage required. In case of charging the batteries in serie from another source but your own, like a shore installation and /or ship you switch your own batteries as the this warningplate says. I guess Dons translation is not bad and my native tongue is not German, but I guess the text reads word by word : In case of charging the batteries in serie from a strange current circuit you should switch together the plus pole port and minus pole stb at the main switchboard.
On the plate below: As Don says
Battery main switch 1

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jul , 2019, 02:07
Hello Mr. Tore and Katuna,


That last post makes a lot of sense now...  The batteries in parallel would allow a high current charge to happen while the U-Boat was in port. When out at sea and high current charge of 1660 amps with the battery in parallel (E-motor Armatures always parallel when charging) and driven by a Diesel engine at high speed with the prop un-clutched. Then at 830/415 amps, the battery in serial and driven by a Diesel at the appropriate lower speeds.

My internet translator and my German - English Dictionary just ain't as good at Mr. Tore's experience...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jul , 2019, 02:50
Hello Mr. Tore,


Overload current of 5000 amps for 6 seconds - It looks like the only thing that could cause that much current would an e-motor or a switchboard short. I would think that if any of the electric motors for the pumps would catch fire and burn up and not cause that circuit to disconnect? Also, I believe that the pumps and motors wiring goes to internal power panels which are fused? Have you ever seen these breakers pop open?


Regards,
Don_


 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 06 Jul , 2019, 08:50

Yikes! Six seconds is an eternity at a dead short or locked rotor amps. That'll get those windings glowing.


I don't recall if I've asked before but, does anyone have any photos or drawings of the Automatic Battery Switch? Even a schematic would be great. Other than a photo of the cabinet door I can't find anything. I could probably come up with a reasonable looking bit of switchgear but it would sure be nice to have a rough idea what it looked like. Did you ever see inside there Tore?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 06 Jul , 2019, 08:54
Almost forgot, thanks Tore and Don. That translation makes much more sense than what I was getting. I think my Google Translate started the weekend a little early.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jul , 2019, 15:27
Hello Katuna,


Pages 406 and 407 in Skizzenbuch; I explain how it all works. The automatic battery switch does not look to be complicated. I have attached the rotary schematic.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jul , 2019, 01:29
Don
Very good I was just looking through my files and realised my drawings were of such quality not worth posting. Anyhow I am posting a bad copy of battery switch no1 situated just opposite the galley. We very seldom had trouble with the switch, as Don says it is fairly simple. 5000amps for 6 sec. seems to be a lot, but the switch is for protection of the battery, the triggerpoint for a massive shortcircuit is 13000 amps. Other electric components had local protection by fuses connected to the starters.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jul , 2019, 04:48
Hello Mr. Tore,


I spent the last 3 days studying the welding machine schematic on Page 415... I believe I discovered the keys to the kingdom and now I think that I understand how it works. I have uploaded the latest version of Skizzenbuch into Dropbox. Would you please take a look at page 415 and let me know what you think?


Did you ever use the port e-motor as a welding machine on U-995 or U-926 as the EO?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jul , 2019, 13:39
Don.
Sorry we never used the port E-motor as a welding machine on any of our VIICs.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 11 Jul , 2019, 08:13

Thanks for the battery info guys. I you stumble across any photos or drawings please post them. I've tried looking for relays and mag starters from that time period but have come up empty. I've worked with a lot of older electrical equipment (not that old though) so I have a good idea of what the layout of components would be but any additional info would be great.


Tore - Do you know if the components were mounted on a rack of some type or were the mounted to a plate at the back of the cabinet? I guess it doesn't make much difference if no one knows what it looks like in there anyway but, right is right.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jul , 2019, 08:34
Katuna.
The components were usually mounted on a rack.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jul , 2019, 12:44
Katuna,


I previously posted the switchboard schematic to drive the E-motors... Here is the layout from u-historia.com and a Skizzenbuch photo.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 11 Jul , 2019, 14:12
Maybe I've been looking at this all wrong. Are the Automatic Battery Switches, located in the Galley and next to the Capt. bunk, simply a circuit breaker or is it the switch gear to shunt series/parallel? I'm looking at the schematic Don put up. I presume the switch he highlighted in blue is what is in the cabinet or is it everything to the right of the green line? I'm a bit thick headed most of the time so I'm a little slow to catch on. It was my belief that the gear to switch from series to parallel was in there but now looking at the schematic, I'm thinking that took place in the Main switchboard.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jul , 2019, 00:25
Hello Katuna,


The batteries are located below the deck as indicated in the u-historia.com drawing and the battery breakers are located as indicated above deck in the Officers' Wardroom and the galley. The circuit breakers just connect the batteries to the E-room.


The port switchboard circuit is drawn in the schematic on the left side of the green line, and the starboard switchboard is not draw in on the right side just to keep things simple, but it would be very similar. The battery parallel/serial switches are on both the port and starboard switchboards as drawn.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jul , 2019, 00:28
Katuna

The Automatic battery switch is a two pole simple automatic circuit switch between the batteries and the main switch boards. when switched on, the automatic battery switch in the galley is connected to the stb. main switchboard in the E-room, and the automatic battery switch next to the CO cabin is connected to the port main switch board in the E- room. The automatic batteryswitches are locally placed protecting circuit switches for the batteries. As battery parallel/ serie switching is a part of the the propulsion control, the switches are placed in the operation control part of the swichboard. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 12 Jul , 2019, 07:53

I've got it now. Somewhere I had read that the ABS cabinet held the series/parallel switchgear. This makes thing much more simple.


Once again, thanks.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2019, 02:49
Hello Katuna,

After reviewing my documentation... I realize I have posted and then deleted a post in an abundance of caution. However, I believe I have got it right this time.

The older "Lever Type Switchboard" U-Boat power distribution schematic shows battery room #2 powering the main port switchboard in the switchboard rack and auxiliary switchboard 1 and auxiliary switchboard 1a in the e-room/aft torpedo room. While battery Room #1 provides power to the main starboard switchboard on the switchboard rack, and to auxiliary switchboard 2 in the control room. This circuit drawing is the first attachment.

The newer "Rotary Type Switchboard" has the exact same functionality, except auxiliary switchboard 1a is powered by auxiliary switchboard 1 or auxiliary switchboard 2. This circuit drawing is the second attachment

Note both the automatic circuit breaker and the disconnecting fuse must be shut for battery room powering functionality.

My personal comments:

Both disconnecting fuses sample the voltage at the transfer switches to the auxiliary switchboards 1 and 2. If there is a short circuit, then through the transfer switches one disconnecting fuse will see B- while B+ is on the battery side. This short circuit will cause the disconnecting fuse to trip the circuit breaker for that battery room.

Does my explanation make any sense?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2019, 04:06
Hello Mr. Tore and All,


If you think about it, the disconnecting fuse makes a lot of sense. Instead of having a huge circuit breaker that can handle and sense nearly 2,000 amps in order to trip may not be the most reliable disconnect. However, the sampling circuit with the disconnecting fuse would have very little current and is only looking for a differential in voltage (with a 6 second time delay) to trip its battery room circuit breaker.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2019, 04:47
Hello Mr Tore,


This discussion brings up an interesting point...


If one battery room is out of service, I assume they could run both switchboards on one battery room (Just put the battery in parallel). However, there would be limitations when running both switchboard in this instance; the e-motors armatures must be in series to limit the current drain on the operational battery room. Otherwise, there would be twice the normal current drain on the one operational battery room if all of the armatures (4) were in parallel...


Does this make sense?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 13 Jul , 2019, 15:46
Just following this with interest.
This may not be relevant but just reading in U Boat War by Buchhiem


"In order to increase pressure on the hydroplanes, the E-motors are switched to high speed.
At low speed, the batteries are switched to run together"



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2019, 19:11
Hello Raymic1,


In this case:

1. High speed would be battery serial (220 VDC unregulated) and the e-motor armatures in parallel (least resistance and higher current flow).
2. Low speed would be battery parallel (110 VDC unregulated) and the e-motor armatures in series (greatest resistance and lower current flow).


The term "switched together" is not technical enough and must be defined? As together in battery in parallel, or as together in battery in series. It looks like he meant Parallel for low speed...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 16 Jul , 2019, 07:49
Then would the fuse and the circuit breaker both be in that ABS cabinet? Those are great schematics.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Jul , 2019, 21:58
Hello Katuna,


Yes, I believe that the automatic circuit breaker and the disconnecting fuse are both in the same small cabinets in the Officers' Wardroom and the Galley. Unfortunately, I do not have any photos of them. If someone visits U-995 perhaps a photo could be captured of both installations...


The images below on the main switchboard switch for the Type IX U-Boat shows some smaller wiring besides the main buss bars for the heavy battery current. The documentation that I have for the Type VII C U-Boat (my translation) indicate that the wiring near the main switchboard switch is for the switchboard battery amp meter (with two switchable ranges) and a voltage meter.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 17 Jul , 2019, 08:58
I'm an AC voltage guy by trade so DC voltage often times frightens and confuses me. However, looking at the schematics, I would think that the DF leg is more of a control voltage. If there is an issue with the motor, such as a cooling problem or clutch issues and amperage is running high, then the DF would blow, disconnecting the main power (supplied from the CB) at the switchboard. If there is a direct short or grounded winding in the motor or supply power, the CB would trip. By definition a circuit breaker is an amperage device. If the DF directly affected the CB, then the CB would actually be a relay or magnetic contactor that is directly commanded by another source.


I'm unfamiliar with 1940's German/European schematics so I'm not totally sure of the symbol used for the CB in Don's schematic. It appears to me to be a switch but it has a couple extra bits to it. In the section below from Tore, it looks like either a manual disconnect or magnetic contactor with overloads located on the load side of that switch.


From a modeling standpoint, I guess this is all moot but it is fun to try and decipher how all this worked. Would sure love to see inside one of those cabinets. Don, your last picture is about what I was expecting the components to look like. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jul , 2019, 17:13
Hello Katuna,
This is my translation of a document which I will email to Mr. Tore  for his comments...

Accumulator system
Page 10 and 11
Safety equipment.
1. To protect against overloading of the batteries, a battery self-closing switch is installed between the battery and the main circuit board with the following tripping option.
a) Over-current triggering adjustable for overcurrent from 3000 - 7500 A and for a delay time up to 10 sec, normal Set for 5000 A and 6 sec.
b) Short circuit triggering adjustable for 11000 - 22000 A, normally set for 13000 A, triggers without delay.
For further information see Description and Operating instructions, main switchgear and auxiliary switchboards.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 19 Jul , 2019, 11:53
Ok, time for a new topic. Mr. Tore, I remember seeing a photo somewhere of the engines and on the "purge" valves (next to the injectors), they had small catch can, presumably tin cans from the galley. I would assume this would have been to catch any oil/fuel/water that would have been blown out while cleaning the cylinders out. Do you ever remember seeing anything like that? Thought that would be a nice detail to add to my engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Jul , 2019, 14:37
Hello All,


I have modified my 16 July posting....


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 19 Jul , 2019, 15:05

I looked a little closer at the switch photo and noticed the fuses on the bottom right. Those are still used today. Those look, physically anyway, to be about the size of a 2000A fuse.


I'm curious, is that a handle in the center to close the switch? Good thing the operator is protected by the lightning bolt labels. Metal handle around all that electrical? No thanks. I give electrical a lot of respect when working around it. If it is a disconnect handle, you'd think they would at least put a wood or bakelite hand grab on it.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Jul , 2019, 16:02
Hello Katuna,


The circuit diagram of the main switchboard and batteries for the Type IX U-Boat (diagram attached) clearly shows the additional fused circuits.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Jul , 2019, 02:39
Hello Mr. Tore,


When surfacing Q Tank is being flooded...  Air is going from Q Tank through the muffler internal to the pressure hull. Is there a means to determine when Q Tank is fully flooded other than water at the muffler?  I must have forgot something during our discussion years ago...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Aug , 2019, 19:51
Hello Mr. Tore and All...


Skizzenbuch: U-Boat Type VII C Project


Copyright (C) Donald M. Prince, Tore Berg-Nielsen,
Maciek Florek, Simon J. Morris, and Mark Hessburg

Published and distributed in the United States of America by
Kristallklar Publishing, LLC

Library of Congress Registration No. TXu002150468
Service Request No. 1-7130055519
Effective Date of Registration: December 4, 2018                                 

First Release Date: August 15, 2019
(with minor corrections)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 03 Aug , 2019, 15:21
Can't wait! Counting the days.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 03 Aug , 2019, 20:08
Awesome. 2 weeks to go....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 04 Aug , 2019, 05:30
Hello Raymic1,


In this case:

1. High speed would be battery serial (220 VDC unregulated) and the e-motor armatures in parallel (least resistance and higher current flow).
2. Low speed would be battery parallel (110 VDC unregulated) and the e-motor armatures in series (greatest resistance and lower current flow).


The term "switched together" is not technical enough and must be defined? As together in battery in parallel, or as together in battery in series. It looks like he meant Parallel for low speed...


Regards,
Don_




Quite a nice easy explanation here from below.
Using the motor - series-parallel - switch and battery - parallel-serial - switch three drive speed ranges corresponding three voltage ranges can be set (see E Sketchbook)
1.Batteries in parallel, armatures in series
2.Batteries in parallel, armatures in parallel
3.Batteries in series, armatures in parallel
[/t]
Within these three ranges, further adjustments can be done by changing the current in shunt windings using the double motor field rheostat.

U-boat Information

for

U-boat Type VIIC
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 13 Aug , 2019, 08:26

Tore - Have a question on the valve wheels that are sticking up from between the rocker arms on the engines. It looks as if they go to the fuel pipe from the injector. In the photos below I have identified what looks like one of the valves and stem on the cylinder farthest forward (my arrow should be a little to the left). I assume this would be to shut off fuel flow to the cylinder if needed. I just need to verify if that is where those small handwheels go to.


As always, thank you.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Aug , 2019, 00:25
Hello Hatuna,


Earlier. I looked in the wrong place on my notes... I believe this valve is the Vent/Drain Fuel Valve... However, it's best to wait for an official answer from Mr. Tore...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 14 Aug , 2019, 08:14
Don - I believe Trumpeter had originally planned on adding a handle and just forgot. If you look at the photo you can see the stems sticking up. I'm sure that's where the handle is supposed to go.


Like you said, best to wait for the man in the know to weigh in.


I wish I could find more of Simon's engine drawings. I have a few plan views and pieces of the side views. They're immensely helpful.

Now that I look at the detail drawing you posted, it looks as if Trumpeter mis-designed the fuel line thinking that was where the valve/handle was at and didn't make a handle. Who knows with Trumpeter. Design by committee.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Aug , 2019, 19:48
Hello Katuna,


There is a missing link in the model...  See my photo...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 14 Aug , 2019, 23:05
FYI
As there seem to be no photos of either battery conditioning rooms the latest Game U Boat has this modelled as their interpretation.
Anyone know exactly what the electrical gear looked like inside?
Thanks
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Aug , 2019, 00:34
Hello Raymic1,


I only have one photo of the battery room where the crewman is laying on a trolly and checking the battery acid...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Aug , 2019, 01:15
If you are referring to the battery buss connections in the e-room to the Switchboard control panel; I only have somewhat of a view for the Type IX Switchboard... I assume there would be shielded copper cables going to the Switchboard connection bars.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Aug , 2019, 01:59
This is a Type IX C photo and the title is "Battery room of a Type IX C-Boat under construction"....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 15 Aug , 2019, 08:18

I think we beat this one to death awhile back. Tore chimed in too. There just aren't any photos or drawings of the cabinet components. Scroll back a page or two and there are a couple schematics and one partial pic of a magnetic switch. It's as good as you're going to get.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 16 Aug , 2019, 16:43
Is it time yet, Don? Just realized today is the 16th.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Aug , 2019, 19:50
Hello Katuna,


I sent a link of the final US Copyrighted version of Skizzenbuch to four (4) Websites on the 14th of August, and they are working on a means for distribution... Since the file size is 715 MB, this does present a problem and they are looking for a solution.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 19 Aug , 2019, 19:49
Hi Don
Thank you for you Tore et all for putting this together over the years.
It will be fantastic to read.


Are you able to share who the 4 sites are and any idea if any of them have sorted this as yet?
Thanks 8)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Aug , 2019, 23:02
Hello Raymic1,

Try this:

https://www.dropbox.com/sh/9is1eocx7qilq4o/AAC6v4TufyFyAcsV8yH08s_-a?dl=1 (https://www.dropbox.com/sh/9is1eocx7qilq4o/AAC6v4TufyFyAcsV8yH08s_-a?dl=1)

Copy the link into your browse and hit return, and the skizzenbuch.zip file will be downloaded

Then click on the ZIP file and then select the PDF and the Folder to be unzipped into your designated folder.

Let me know if this works....

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 19 Aug , 2019, 23:35
Hi Don
This has worked perfectly.
Fantastic . I have a lot of reading to do.


thanks
Raymic ( Mike)



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 19 Aug , 2019, 23:46
Hi Again Don
I've had a quick preview and you guys have done a fantastic job. This will be an awesome resource for the U-boat community.
Fantastic that this knowledge has been passed on for future generations of enthusiasts and historians.
Well done. Much appreciated.
cheers
Raymic ( Mike)'

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Aug , 2019, 01:10
Hello All,


Just in case you were worried... Mr. Tore and his wife are on a vacation at their farm and he has limited internet (Slow) access. They are celebrating his wife's 90th Birthday. Somehow, at 78; I feel old and tired at times... There must be something in the water in Norway for people to have such good health and longevity!


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Aug , 2019, 15:07
Hello All,


The websites are:
1. This AMP website
2. Jerry Mason's www.uboatarchive.net
3. The Subcommittee www.subcommittee.com
4. And possibly www.u-historia.com


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 21 Aug , 2019, 09:36

Don - What a wonderful piece of literature. There are some very interesting bits of information in there. I just gave it a quick glance front to back but I'm looking forward to sitting down the weekend and reading through as much as I can digest in one sitting. You have done a masterful job. A huge thanks to you and all of those who assisted.


I would love to see this in print. I'm old fashioned. I like having a book in my hand. I will say, however that it is nice for my aging eyes to be able to zoom in on a photo rather than squint at it.


PS  - Glad to hear Tore is on vacation.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Aug , 2019, 13:07
Hello Katuna,


Skizzenbuch is protected to not permit changes to be made, but I did not protect it from being printed. I know most PDF protection can easily be hacked and that is the reason for the copyright. I took Skizzenbuch and had a previous version printed at a print shop on card stock paper and that cost over $200. I since trashed the printed copy because I have made many corrections and additions. I plan on printing it again in a 11 x 17 format on glossy card stock 80 pound paper. I have a leather bound metal post binder (the main reason for the 1.75 inside seam), so the book will be about 2.5 inches thick with the Wallet Folder in the back of the book. The card stock, printing, and the post binder total cost is about $500.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 21 Aug , 2019, 16:02

Yikes! Well, computer version it is then. Let's see, if I print 10 pages a week at work, it'll only take me a year to print it out. Yeah, that works for me!


I'm sure there will be people that would love the leather bound copy. It's a great assembly of highly detailed information.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Sep , 2019, 03:45
Hello All,

It looks like Skizzenbuch has been available on the Subcommittee website for about a week under "The U-boat Pen" forum and has had quite a few downloads.

Thanks to Wink Grise and Dougie Martindale Skizzenbuch is now available on the AMP website in the section book/submarines/Uboats:

https://amp.rokket.biz/lib_uboats.shtml (https://amp.rokket.biz/lib_uboats.shtml)

I will provide other updated when they become available...

Regards,
Don_




Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 12 Sep , 2019, 09:01
I have just thumbed through the book. Holy cow!  An amazing work.
Whatever happened to the fellow in this thread who was making a 3D model of a uboat?
Hope all is well with Mr. Tore these days.  I have not been back here in a while.

Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Sep , 2019, 18:34
Hello Mr. Tore, Simon, and Mark...
You all will have mail in a few days.
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Sep , 2019, 17:25
Hello Mr. Tore, Simon, and Mark,


I got the packages for Mr. Tore and Mark back from the USPS and had to re-send them today. I have no idea if Simon's package was sent on to New Zealand or was lost by the USPS. We'll find out in a week or so...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Oct , 2019, 01:45
Hi Don and everybody.
I am finally back after my vacation and a lot of other events. First of all Don, thanks for the DVD which I got in the mail today, the box was slight broken, but I guess the disc is OK. As I have no DVD input on my PC I have mobilized my grandchildren to help me with the hardware, looking forward to seeing the final result.

I the meantime I found a few images from KNM Kaura ex U 995 up at my summerfarm they might have some interest beeing shot in 1953 above the polar circle in northern Norway and actually in the area where U-995 did her WW2 patrol watching the convoys to Murmansk.
I have a few more never been published if any interest.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Oct , 2019, 02:26
Hello Mr. Tore,

The previous page and my response to Raymic1 which has a link that does an auto download from Dropbox which contains the final released and copyrighted version of Skizzenbuch and the folder that contains 10 huge prints. I will repost the link...

https://www.dropbox.com/sh/9is1eocx7qilq4o/AAC6v4TufyFyAcsV8yH08s_-a?dl=1 (https://www.dropbox.com/sh/9is1eocx7qilq4o/AAC6v4TufyFyAcsV8yH08s_-a?dl=1)

The CD is about 99% full with the PDF and the Wallet Folder.

Any new unpublished photos are always desired...

Regards,
Don_

PS: the Skizzenbuch link on the www.subcommittee.com (http://www.subcommittee.com) website at "The U-Boat Pen" looks to have had over 160 downloads to date...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Oct , 2019, 05:26
Don and all
In september 1953 we did a schnorchel testrun Bergen Norway,- Fareoe Islands - Bergen, 17 days submerged, a pretty long time in those days. Here is an image of the officers on the bridge I`m in the centre returning to Bergen. The other image is returning to the submarine pen in Trondheim a bit later same year. My private photos not published before.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 02 Oct , 2019, 08:25
Those pictures are brilliant! Would love to see any of your photos.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Oct , 2019, 10:39
Katuna.
Something happened to my last post, it seems everything disappeared. The front of the U-995 engines seems to cause some trouble. As from 1943 the idea was to get rid of some extra weight particularly on the VIIC/41 due to the increased diving depth keeping the same enginepower a few weight reductions were carried out on on the submarine. On the GW engines this involved removing the direct reversing mechanism including the double camshaft and the huge reversing cylinder on the top of the engine up front. The submarine was manoeuvred by the e-motors in an easy way, saving a lot of HP air. On some engines like the U-995 you`ll still find some rudiment parts like the reversing handle etc. Below I have tried to identify the various items at the front of the engine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 02 Oct , 2019, 13:49
Well, I'm glad I asked you before I scratch built one. Thank you for the photo with the identifiers.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2019, 00:33
A few more old images KNM Kaura ex U 995   1953-54
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 03 Oct , 2019, 05:49
Wonderful photos Mr Tore. Thanks for sharing.
Is that your Captain on the Attack periscope in photo 11?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2019, 05:57

Raymic
Indeed he was one of the pioneers of our VIICs and a good friend of mine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2019, 11:12
A few more private photos from KNM Kaura 1953-1954
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Oct , 2019, 03:14

Just for fun, here is an image showing Hans Georg Hess the last CO of U 995 visiting the U 995 museum a few years back and the first CO of KNM Kaura ex U 995  Nils Tiltnes in 1954.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Oct , 2019, 03:08

A  photo from KNM Kaura showing the helmsman while running surfaced on diesel watching the removable gyro repeater.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Oct , 2019, 01:19
Hello Mr. Tore,

I'm now back to looking at the Type IX C and C40 U-Boats... Unfortunately, I don't have Maciek for guidance anymore. I'm looking at the rudder control and I understand some of the electrical schematic. I'm not certain about the "Self Starter" device. It looks to be a driven set of cams which may change the switch contacts after movement has started.

Do you know someone that I may communicate with to get a precise understanding of this circuit?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Oct , 2019, 02:40
Don.
 As so many of my crew have passed away including my 1. electrician who for sure would have been able to answer, I am sorry not being able to help you. I was never involved in this stuff.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Oct , 2019, 01:01
Hello Mr. Tore,

I have been able to figure out some of the circuitry on my own after several hours of study...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Oct , 2019, 03:18
I have been briefly looking at the large scale models of trumpeter modelkit and am impressed about the ambitions rather than the results of the kit maker, it is however impressive what some of the modelbuilders have achieved. My memories goes back to the days we were crawling under the floorplates trying to figure out  how things worked without any drawings or manuals in the first years. The way some of your guys are able to model the piping system is awesome. On order to have a correct system it helps to know how it works and below is an image of the lubeoil system up front of the port engine of U 995 having a non reversible GW engine without lubeoil purifier (sentrifuge) .
The system works as follows: Each engine has a dry oilsump with 5 drainages to a common drain pipe leading to a double valve cage being able to select port or stb system tank. The attached gearpump up front is able to operate in two turningdirection (a complicated rudiment from a direct reversible engine) takes suction via a suction valve from the relevant systemtank to the suction side of the pump, before entering the pump is a smaller branch pipe with valve to the discharge pipe and from the discharge of the pump is a small pipe with reliefvalve to the engine drain pipes.  The dischargepipe has a thermometer and then a NR valve before entering a valvecage having connections to port filter and cooler, stb luboilsystem and the emergency lube oilsystem. The cooler has on the top a venting pipe with cock, the ventpipe ends in the common main drain pipe of the engine.  The cleaned and cooled lubeoil leaves the cooler via a three way cock enabling connection to port engine, stb. engine or bypass. After this cock is a branch of pipe ( full pressure) to the governor servo motor (aft of the engine) which has a drain to the common drainage pipe. The main lubeoil pipe now passes very visible the front of the main engine where a pressure reduction valve is situated reducing the oil pressure from 3kg/cm2 to 1,5 kg/cm2. Then a thermometer (in mainengine) before branch off to the various components of the engine like main bearings, register drive, turbocharger etc.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Oct , 2019, 07:34
Don.
I recall we discussed the turning of the VIIC main diesel, I guess in connection with the Skizzenbuch, at that time I couldn`t remember exactly where you engaged the turning bar on the engine. I just discovered an image showing the item as shown below. The manual turning of the main engine was always necessary during maintenance and adjustment, furthermore we always turned the engine manually with open indicator cocks in the event of water intrusion to prevent waterstroke. As you shall see from the image the turning bar system was identical to the main clutch and engaged a "disc" just before the dieselclutch. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: maillemaker on 08 Oct , 2019, 11:00
Hello Mr. Tore,
The pictures are fascinating.  I love seeing them.
Were the stanchions/handrails on deck added post-war?  Did they stay on when submerging?
Thanks,Steve
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 08 Oct , 2019, 11:13

Tore - You are absolutely right about knowing what the components are, how they work in conjunction with each other and how the piping and electrical is laid out in regards to modelling. While Trumpeter did an admirable job of creating a cutaway model, they left an enormous amount of detail out. Those of us that have an inner masochist have decided to twist the knot a little tighter everyday by trying to convincingly recreate as much of the intricate detail as possible.


I grumble about not having a certain drawing covering the specific area I'm working on at any given time. I can't image how you actually operated without any manuals. When men were men.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Oct , 2019, 11:45
Hello Mr. Tore,
The pictures are fascinating.  I love seeing them.
Were the stanchions/handrails on deck added post-war?  Did they stay on when submerging?
Thanks,Steve

Steve, the stanchions and railing were originals, surfaced and submerged, however they were easy removable. For war patrols, and exercises they were removed as they were ratling quite a bit submerged.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Oct , 2019, 19:25
Hello Mr. Tore,

I believe I figured out how the Rudder motor drive circuit works, and here are the other 2 options for the circuit...

Also, the exact same electrical devices were in the Type VII U-Boats. However, the Type VII electrical diagrams only showed small boxes and not the internal details. In fact, the Type VII electrical schematic did not even identify what the boxes were... Go Figure!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Oct , 2019, 02:38
Hello Mr. Tore,

Manually cranking the diesel engine: I figure at most only 3 cylinders would be flooded because the exhaust valves would have to be open to allow water to enter (Some stage of the exhaust stroke). If the engine were manually cranked, then some water would exit the exhaust valves into the exhaust pipe and could be drained into the bilge (besides the exhaust test valves)? Does my drawing look anywhere close to being correct?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Oct , 2019, 11:07
Don.
Your drawing of the turning device is excellent.

I guess the flooding normally is due to leakage of the outboard main exhaustvalve just before the silencer. The valve has a rotating valve disk driven by a pneumatic motor grinding the carbon deposit from the valve seats. This was carried out at regular intervalls running surfaced and as a routine during the diving procedure, the grinding was stopped when the sea pressure became too excessive. Sometimes (not often)this grinding when diving was incomplete due to lack of time and a substantial leakage could occur. When the leakage exceeded the internal draining capacity, flooding happened and water intruded the hull main exhaust valve casing, this valve is susceptible to carbonizing as well and leakage leading to flooding of the exhaust manifold alongside the engine. The manifold has a considerable drainage capacity hence the flooding was very short, but I guess in that short time all the exhaustvalve ducts in the cylindercover were filled and could not be drained by the exhaustmanifold drain. Hence some water was trapped in the cylinderhead exhaustducts. When turning the engine by hand you opened the  exhaust valves and drained this water into the cylinders. In order to get rid of the water could either blow it out by starting air through the indicator cocks running the risk of turning the engine uncontrolled by air with a possible risk of waterstroke or by cranking bar sqeezing the water out through the indicatorcocks by the piston.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2019, 22:02
Hello Mr. Tore,

I actually had a photo of the diesel engine manual cranking dogs, but I missed then right in front of me nose...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Oct , 2019, 03:01
Hello Mr. Tore,

After reviewing my Uboataces DVD I believe I found one of the Self-Starters for the Rudder or the Hydroplane control circuit in the Aft Torpedo Room. What do you think?

Regards,
Don_
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Oct , 2019, 03:29

Don.
I am a bit rusty on this item, but I guess it is OK.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Oct , 2019, 01:30
Hello Mr. Tore,

Does my comments make any sense about the Hydroplane control circuits?

This hydroplane drive system schematic for the Type IX U-Boat look very similar to the lower half of the Type VII schematic. However, the difference is the Type IX actually had the emergency steering unit. The extra BBC unit was mounted on a pedestal directly behind the hydroplane operators in the U-Boat control room. Notice the bow torpedo room self-starter box has a heater circuit and the stern/aft self-started box does not have one. However, the stern/aft self-starter box does have serial resistance (Ns Vorwiderst) added to the hydroplane motor shunt circuit which could act as a heater, and the current flow is decreased in the aft hydroplane shunt coil; more power for the aft hydroplane motor? For example, the U-Boat is running forward and coming to the surface at a horizontal position; the bow hydroplanes up angle determines the rising angle and the aft hydroplanes down lift the back of the U-boat to keep it level (This circuit may only apply to Type IX U-Boats). In addition, the hydroplane motor circuit has a series resistor for the purpose of displaying the Amps drawn.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Oct , 2019, 02:21
Don.
The title of your book is Skizzenbuch: U- boat type VIIC Project, hence I guess it is correct to make it very clear to the readers when you introduce a IXC topic in a VIIC publication to prevent confusion and misunderstanding. Allthough there are many components of the same design in the two submarines types, they are different and mixing the two in your book might lead to confusion to the layman.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Oct , 2019, 14:50
Hello Mr. Tore,

My questions:
1. Coming from depth to 20 meters - Would the captain bring the U-Boat up at a forward angle up, or the U-Boat up while positioned horizontally/level? I would think at a forward angle up for expediency.
2. Going to periscope depth from 20 meters - The captain would want the U-Boat level when going to periscope depth because he would not want a bow up angle.
3. At periscope depth - Take on some water ballast and make the U-Boat heavy, and use the forward and aft hydroplanes up position and maintain a horizontally level U-Boat at depth with a low periscope exposure.
4. Speed at periscope depth - I would think a higher submerged speed would provide the captain with greater control of the periscope depth exposure.

Regards,
Don_

I agree with you; I do not want to introduce U-Boat Type IX data into Skizzenbuch for the Type VII U-Boat. Since the Type VII U-Boat electrical circuit data is not detailed, then perhaps some of the more detailed Type IX electrical information applies to both U-Boats. If the above questions applies to both U-Boat types, then perhaps the electrical designs apply to both U-Boats as well? Fortunate for me, you are a very rare resource over 90 years old with actual Type VII U-Boat experience. I'm no spring chicken at 78 years old either. My area of expertise was electro mechanical equipment and the electronics (tube and solid state) of the past generation. I may ask questions beyond your area of expertise or responsibilities as the EO of Kaura, but there is no one else left to ask... Congratulations!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Oct , 2019, 00:25
Don.

It is difficult to make a general rule for changing depth, it all depends on circumstances and the COs skill and experience. Generally being submerged you change your position dynamically eg. using hydroplanes and speed which means moderate bow up going up and bow down going down. To compensate for changes in water density and hull compression you use the regulating tanks and for crew movement you use the trimtanks. If the CO want to go to periscope depth you usually go dynamically to see if you are able to hold the boat there, depending on the surface condition like waves etc. I have experienced swell down to 50 meter. Surfacing you take the boat up dynamically and carry out a periscope sweep before blowing the main ballast tanks having the bow slightly up towards the wind and waves. When breaking the surface the boat has a low stability and you want to avoid the weather hitting you atwartship. But every COs has his liking based on his experience. The image below shows not how you should do it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Oct , 2019, 13:42
Hello Mr. Tore,

It's amazing how your brain recovers after a few good nights sleep... Now it's quite obvious to me that the additional hydroplane motor current for the aft/stern hydroplane is common for both the Type VII and the Type IX U-Boats. In order for the stern/aft hydroplane motor to overcome the prop wash pressure, the motor drive circuit for the stern/aft hydroplane requires the additional motor drive current.

What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2019, 23:59
Don.
Sounds reasonable to me. But as mentioned before I am a bit rusty on this topic. In the meantime I have been looking at some old drawings previously mentioned and I found some VIIC el schemes which I am trying to restore, not very successful though. I am posting a couple showing part of the scheme for the rudder, aft and fore-hydroplanes. As all the drawings are in a mess and the blueprints of bad quality I am not sure it is of any help to you. I might be able to restore some more ( take some time) if you think they would be helpful.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Oct , 2019, 02:07
Hello Mr. Tore,

Your original Schematic shows a little more of the wiring, but not all and the circuit items remain a empty box like the Type VII schematics which I have... See attachment.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Oct , 2019, 02:26

Don.
 Just what I expected, the schemes are from Blohm and Voss a german shipyard building VIICs .
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Oct , 2019, 16:49
Hello Mr. Tore and All,


It looks like the link to download Skizzenbuch on the SubCommittee.com forum/The U-Boat Pen website has just exceeded 300...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 30 Nov , 2019, 10:21

Its been far too quiet around here lately so I have a question for Mr. Tore.


I came across this photo on another site and found it quite interesting, to say the least. My question, however is, what is the round hatch that's open just aft of the engine room? Of course I have no idea if this is a Type VII or IX boat. I looked at Simon's plan view of his boat and I didn't see any hatch between the exhaust. It's too far forward and too high to be the aft torpedo loading hatch or am I mistaken?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Nov , 2019, 15:11
Katuna.
The engine hanging in the air seems to be a 6 cyl. direct reversible Krupp Germaniawerft engine as installed in the VIIc`s up to 1942. The Roots supercharger is removed and you see the outboards side of the engine with the combustionair manifold. There are not too many detailed images of the outboard side of this engine. I don`t fully understand your question on the circular hatch aft of the engine room, but the the large circular pipe in front of the engineroom is the flange of the large dieselair shaft coming from the dieselair intake valve operated from the controlroom. This shaft enters the engineroom just above the maneuvring places in the front of the engineroom where it is split in two ducts ending above the bilge at the outboard shipside port and starboard away from the combustion airinlet of the airmanifold to prevent seawater intrusion in the airmanifold..
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 30 Nov , 2019, 15:37
The round hatch I have circled in red. It is indeed rare to see any photo of the outboard side of the engines.

Could you possibly post that drawing by Simon by itself? I've never seen that one before and it would be most helpful at the stage I'm at with my model. I tried enlarging the pic you posted but it comes out much too blurry.

As always, thank you for your wisdom.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Nov , 2019, 16:24
Hello Katuna,

Perhaps these drawing by Simon J. Morris will answer your question. The upper pressure hull rivets were removed from the upper pressure hull plates above the diesel engine room to provide the huge opening as seen in the photo.  I was discussing this with Simon back in January...


The hatch circled in red is the aft torpedo loading hatch (Last Drawing)....

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2019, 02:52
The round hatch I have circled in red. It is indeed rare to see any photo of the outboard side of the engines.

Could you possibly post that drawing by Simon by itself? I've never seen that one before and it would be most helpful at the stage I'm at with my model. I tried enlarging the pic you posted but it comes out much too blurry.

As always, thank you for your wisdom.
Katuna

Don got your question right and Simons images shows clearly the aft torpedo loading design. I might add that the angle of the loadingtrunk makes locally a considable weaking of the pressure hull as frames 15,16 and 17 are cut making the oval opening in the pressure hull. As can be seen from my image below if you disregard the modern lights and wiring, this is compensated by putting removable strengthening beams across the oval hull opening. The beams have a clearance of appr 20 mm at the contact points and being submerged the compression of the pressurehull elimitate this clearance. The solution is common to most submarines from the VIIC vintage.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Dec , 2019, 15:47
Hello Mr. Tore,

We had discussed the frames in Skizzenbuch with reference to the torpedo Tube loading hatch. However, we never touched on the subject of replacing a diesel engine and the disposition of the diesel room frames. The attached photo shows the upper frame missing while workers are in the diesel engine room. From this vantage point, it looks like these frames were cut into sections, but we never discussed the joining method for these frames.

Update: I found a photo on my U995 DVD that shows where the frames upper section in the diesel room overlap and are riveted together. See second image below...

Regards,
Don_

PS - I noticed that the ModelShipWorld.com (Where Katuna's photo was posted) used Skizzenbuch's colorized Plate 13 of the G. W. Diesel Engine drawing...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Dec , 2019, 00:47
Don.

The large engineroom opening for mounting the mainengines was as you know shut by a large riveted plate strengthened by riveted frames as can be seen from Falos photo below. The frames above the engine have supports for removable round bars above each cylinder. These bars were used as fixing point for winches for maintenance work like lifting cylindercover, cylinderliner, piston and pistonrod etc. You would need every inch above the cramped place to lift the parts from the engine. The riveted  plate was only removed in case of a major dammage to the cylinder block, crankshaft or bedplate.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Dec , 2019, 03:43
Hello Mr. Tore,


Thanks for the info, I will add that to the Addendum Booklet. Is that person's name Falo or Falos as in your response...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Dec , 2019, 04:50
Don.
Falo is a member of this group, you`ll find him in the members list, he has kindly allowed me to use his photos taken during his visit to U 995 at Laboe.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 03 Dec , 2019, 08:49

As to the hatch, it makes sense that it is the torpedo loading hatch now. It just seemed to me that it was located lower in the hull and wouldn't have been that visible when open. My mistake.


Tore, that overhead photo of the lifting bars is very interesting. Never realized that how they would rig the top end of the motor apart. Another question, where exactly were the engine spares carried? I know I had seen a photo somewhere (U-534 perhaps?) of a piston and a rod (?) that were stowed on the decking plates of the engine compartment. Would the area on top of the waste oil tank between the engines be used for storing spares crates? I would imagine, especially during the war, that spares would be crammed everywhere there was a cm to spare.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2019, 00:30

Katuna, storage space for major engineparts was hard to find. I guess we found different places and volumes depending upon the mission of the sub. We usually operated along the long coastline of Norway and carried minimum of spareparts as we could get same by plane anytime. However when we took over our VIICs we found major large parts fixed to the pressurehull between the engines and the pressurehull as indicated on my image below. On U 995 I particulary remember a "barrel" containing a piston, the "barrel" was filled with conservation oil and fixed to the pressurehull in the engine room. For some reason I had to check this piston and opened the barrel putting my hand down to the piston. I was newly married and my weddingring slipped off the finger and disappeared down in the oil. Of course a disaster and with helping hands from my engineroom crew we were able to retrieve the ring at the bottom of the barrel after substansial work. Otherwise we got parts by plane fairly easy from our large storage ( called the Fox garden) in the submarine pen at Trondheim. Consumable parts like fuelinjectors, exhaustvalves etc were of course kept onboard. Otherwise you`ll find empty storage bins made by steel straps throughout the U 995 often used for hoses etc.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 04 Dec , 2019, 10:18
I had noticed on U-995 that there are racks located on the pressure hull behind and slightly above each engine. I wondered if these were original or from its time in Norway. When you say "barrel", do you mean like a wooden barrel/keg or a metal canister? I love modeling little details like this but I want to get it correct. In the photo below, I'm assuming those are the stowage racks?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Dec , 2019, 10:43
Katuna, I can`t remember exactly, but I guess the pistoncontainer was made of steelplate and the lid secured by a steelring over a fold on the top. Barrel is a wrong word in this case. As to the stowage racks/bins I assume they were originals.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Dec , 2019, 23:39
Hello Mr Tore,


The photo below shows the lubricating oil pump and housing with 12 lubricating lines to other locations on the GW Diesel engine where the oil pump just didn't provide the needed supply of lubrication oil. I see where there is an eye sight glass for viewing the housing's oil level. Was there an internal float level valve to assure an adequate Lubricating oil level?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2019, 01:00
Don.

The device on your image is called a lubricator which supply a calibrated oil droplet to various items on the engine. The system is common to most  large marine diesels. The device consist of a housing containing luboil ,the level is shown by a sight glass at the container.The working principle is that a camshaft is mechanical driven via a ratchet this camshaft operate several plunger pumps taking suction from the luboilcontainer inside the housing. Each plungerpump supply an adjustable droplet to the its lubrication point, this droplet is discharged to a waterfilled sightglass enabling you to check the supply. from the individual sightglasses is a small pipe leading to each individual lubrication point.  Below is an image showing a pipe to the exhaustvalve stem in the exhaustvalve casing.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2019, 02:18
Hello Mr. Tore,

"this droplet is discharged to a water filled sight glass enabling you to check the supply. From the individual sight glass is a small pipe leading to each individual lubricating point."

The sentence - "this droplet is discharged to a water filled sight glass enabling you to check the supply." How does this work?

It sounds like you are mixing oil and water?
See the image below... I found this on the internet, but I don't really understand what I'm looking at?

I assume you are seeing something inside the lubricator through the two rectangular windows in the front of the lubricator.  What is the purpose of the elongated window on the side of the lubricator?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2019, 04:15
Hello Mr. Tore,


I found this on the internet... I don't fully understand it, so perhaps you can help???


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Dec , 2019, 07:14

Don you have many systems to handle the distribution and counterpressure for lubricator as  your page for handling the steamcounterpressure for lubricators of the steamengines. You have similar system for cylinder lubrication of largebore marine diesels, however I guess the lubricator for the GW engine is a bit simpler. I never dismantled the GW lubricator and unfortunately I have no image of the lubricator as installed on the GW engine,  but I guess it works as follows: The plunger pump takes its oil from the oil oilchamber in the pumpcasing (the oillevel can be checked by the level glass in the lubricator casing) and discharge to the discharge sight glass filled with water kept in the glass by  springloaded inlet and dischargevalves. In the sightglass a certain volume of the  oil is permanently collected at the top of the sightglass due to a lesser specific weight of the oil than the water. As the oil is forced by the plunger in to the sight glass  it displaces the same volume of the oil on the top and this oilvolume is discharged through the discharge NR valve to the lubeoilpipe connecting the lubrication point. The sight glass checks the working of the lubrication and the volume discharged to the lubrication point, (permanent volume of the oil on top.)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 05 Dec , 2019, 08:33

If I understand correctly, the sightglass on the forward end of the lubricator (the vertical glass) shows the level available in the lubricator reservoir itself. The feed to each oil pipe comes from the individual sightglasses located on the front (behind the two horizontal windows) and these glasses have water in them to a predetermined level. The oil floats on top of this and, as the feed to each lubrication point is increased or decreased, that level indication in the glass moves up or down.


I defer to the honorable Mr. Tore however as I'm taking a semi-educated guess.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Dec , 2019, 16:04
Hello Mr. Tore and Katuna,

Question 1: What is the cylinder number for the cylinder closes to the maneuvering panel???
Question 2: The 12 hex head screws on lubricator, are they just for holding/attaching the lubrication lines???
Question 3: Where are the needle screw/valves to adjust the drop size to the sight glass located???

The last two posts look to be spot on as far as to how the "Lubricator" actually worked.

Another thought - the oil level in the sight glass tube would remain at a constant level because as the diesel engine speed increases or decreased, then the rocker arm drive would increase or decrease the number of oil drops provided to the sight glass tube and in turn provide more or less oil to the cylinder chamber through the non-return valve. The adjustment of the feed needle valve will increase or decrease the volume of the oil drop which results in more or less oil forced from the upper oil area of the sight glass and through the non-return valve providing more or less oil to the cylinder chamber. So, again the oil level at the top of the sight glass would remain at a constant level???

Perhaps the only way to change the oil level in the sight glass is to decrease the internal water level and the sight glass internal pressure will still be maintained (don't want to change the oil feed pressure). And another thought - why not just fill the sight glass with oil; that would still work for lubricating the cylinder chamber. However, Having water in the sight glass you can see the oil drop rising which is a visual verification that the Lubricator is working!

I have been doing some reading about marine Diesel engines on the internet. When the Diesel fuel oil ignites in the cylinder chamber sulfuric acid is created which will corrode the pistons, piston rings, cylinder sleeves, valves and valve seats, etc. The lubricator has 12 lubrication lines which go to the 6 cylinders on the GW Diesel engine (2 per cylinder). The cylinder lubrication oil has a special property (addictive) which neutralizes the sulphuric acid to counter the corrosion effect after ignition. If you look closely at the lubricator there is a large filler cap on the top. I believe when the oil level gets to be low, then it's the responsibility of the Diesel engine operator to refill the lubricator. This could be a normal scheduled maintenance procedure after a normal 4 hour shift.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2019, 02:20
Don and Katuna. I am afraid my post and assumption was not 100% clear and even uncorrect on some wordings. I guess it should be possible to find some details on the lubricator as the firm making the lubricators still exist. I guess the name is Gruetzner GMBH in Germany may be someone are able to retrieve some documents from the net. In spite of an old construction it might be some drawings exist. As to the lubrication points on the GW engine I can`t remember any cylinder lubrication, in fact as the GW engine is a trunk engine where you normally have a tendency to draw to much luboil up in the combustion chamber getting a too high luboil consumtion, hence the trunkengines have piston oilscraper rings scraping oil down to the sump. As far as my fragile memory goes the point lubrication were on the valve stems in the cylinder head, see my image below. In addition I am showing the filling lid on the lubricator which is manually topped up.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2019, 04:09
'Gruetzner GmbH has been a specialist in automatic lubrication systems since 1993. We find the optimal solution for your lubrication points. You save time, costs and increase the longevity of your machines. '

Your images - I could see one line going to the exhaust valve and one line going to the cylinder???

Could not have been them...
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2019, 04:42
Hello Mr. Tore,

Here is where I was getting some info on Marine Diesel engine lubrication...
https://www.marineinsight.com/tech/ships-main-engine-lubrication-system-explained/ (https://www.marineinsight.com/tech/ships-main-engine-lubrication-system-explained/)

They have some great videos!
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Dec , 2019, 06:14
Don.

I had a quick look at the videos of the marine diesel, as far as I can see the videos are dealing with two stroke large bore marine diesels running on  heavy fuel, which often contains sulphur and in some cases residues from the fuelcracking and need special treatment. The GW engine is a four stroke medium speed trunk engine running on dieselfuel usually have a higher quality than heavy fuel , and mostly don`t require a cylinder lubrication as the piston and cylinderliner is in direct contact with the crankcase and system oil. A crosshead engine has a fixed pistonrod above the crankcase sealed from the crankcase by a packingbox around the pistonrod. After the packingbox is a conrod having a upperbearing in the crosshead and a lower (big end bearing on the crankshaft) in the crankcase.  This system usually requires a cylinderlubrication. The reason for having a crosshead is that you have a separate guide (crossheadshoe on a sliding face) which takes up the large sideforces in a special sliding component having a separate lubrication system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 06 Dec , 2019, 09:40
That's very interesting. I never realized they used a crosshead like that. Just like a steam locomotive only vertical.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2019, 16:15
Hello Mr. Tore,

I think your original description was correct about how the Lubricator functioned. I think the lubricator used the lubrication oil onboard (Clean Oil); the reason for the lubricator having it's own source of oil was because they didn't want to use the engine circulated Lube oil source because it was dirty and picked up impurities and carbon. They didn't want to dirty up and plug the Lubricators flow lines and journals. There is also the possibility that the U-Boat Lube Oil was of a higher quality with some additives to counter any sulfuric acid created during combustion. After all, the U-Boat was an advanced piece of machinery which was vital to Germany's war effort.

I'm still doing some internet research on Diesel engine lubricators...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Dec , 2019, 21:28
Hello Mr. Tore,


The Japanese still make the Lubricator... www.yasec.co.jp (http://www.yasec.co.jp)


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Dec , 2019, 00:35
Don, I don`t think the GW engine requires a special luboil to compensate for the sulphurecontent in the diesel fuel. The major problem for a submarine luboil is water emulsion. As we have discussed before a submarine diesel is susceptible to waterintrusion contaminating the lubeoil. In some cases the luboil gets emulsified which ruins the lubrication properties of the oil, hence you want to have a lubeoil with additives that counteracts emulsion, this is in contradiction to the old time steam engine where we were squirting water on the crosshead guides to make luboil emulsion. On KNM Kaura ex U-995 I experienced twice a ruin of the luboil due to emulsion caused by water intrusion, in spite of separate lubeoil systems, the operation is costly.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2019, 01:09
Hello Mr. Tore,

When surfacing from a dive:
1.  Use HP air to blow the cylinders with the test cocks open to assure no water?
2.  If water is seen, then you would manually crank the engine with the test cocks open to clear the water form the cylinders, or would HP air do the job alone?
3.  Manually crank the engine with the test cocks open to clear the water from the cylinders, If the CO will not permit the increased hull pressure.

Basically would the use of HP air or manually cranking be the standard starting procedure?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2019, 03:58
Don.


HP air (205 kg/cm2 as stored in the hp air flasks) is a vital important medium to a submarine, topping up same is noisy and takes time, hence you try to save the HP air as much as possible. Surfacing happens under many different situations and the procedure varies under the various conditions, like the activity on the surface, the submarines depth, weather and the reason for surfacing. The ideal surfacing is as mentioned before, ascending dynamically by speed and hydroplanes, checking the surface by periscope and then blow your tanks at periscope depth using as little HP air as possible, this takes an experienced man as the air in the ballast tanks expands after you have shut the blowingvalve. The idea is to get the submarine in a stable semi surfaced position, then switch over to exhaust blowing, starting with the ballast tanks highest up ( least backpressure) until you are on the required draft. The exhaust blowing is not commonly used on all submarines. In the RN the final blowing is done with an electrically driven LP air blower but the purpose is the same, saving HP air.
The intrusionof seawater into the engines is not a frequent reason during normal surfacing, the most common reason would be during diving via the outboard main exhaustvalve (before the silencer) having a major leak due to carbon formation on the seatings. As you know the valvedisk on this valve was rotated by a pneumatic drive during diving, this grinding was not always successful as the possible grinding intervall was too short (Beckpressure became to big on the valve) causing a massive leakages into the exhaust manifold on the main engines and the via the exhaustvalves into the cylinder and luboil system .
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2019, 04:41
Hello Mr. Tore,

My question was which method is the normal operating procedure:
1. Manually cranking the diesel engine before startup?
or -
2. Using HP air to blow the cylinders out before startup?

Regards,
Don_ :)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2019, 04:49
Don.
When you had a massive intrusion of water after a dive we always were careful when starting the engines. Of course the indicator cocks were open, I preferred to turn the engines manually, some times the water was squirting out of the cocks. Blowing by air was risky as you was using the startinghandle to admit air into the cylinders and you could run the risk of turning the engine by air and get a waterstroke as a result. Blowing through was a starting procedure for checking by a skilled man and not when you have a massive waterintrusion. Turning the engine by hand needs no permission from the CO as it does not influence the submarines internal pressure as pneumatic grinding and airturning would do.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2019, 05:19
Hello Mr. Tore,


Thank You that was exactly what I was looking for...


I apologize, but another question... If when cranking the engine and you got water from the indicator/test cocks, How did you check the lube oil supply tank or the crank case for water?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Dec , 2019, 05:30
Don.
We always checked the lubeoil visually any emulsion would immediately change the colour and  structure of the oil to grey mayonnaise.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2019, 16:01
Hello Mr. Tore,

Once, you cleared the cylinders of water, the lube oil in the crank case and the lube oil supply tank would not have emulsified yet because the Diesel engine has not been running to mix the oil and water; any water that passed through the piston rings would be in the bottom of the crank case or the lube oil supply tank?

The crank case on the GW Diesel engine looks to be fairly shallow, so would all of the water settle down to the lube oil supply tank?

Is there a valve or plug at the very bottom where you could drain the crank case or the lube lube oil supply tank before startup because the water would have settled to the bottom of those tanks?

If you did not have time to test the crank case or the lube oil supply tank, then would you switch over to running on other lube oil supply tank. Now, both engines are running on the non-contaminated lube oil supply tank until you have time to inspect the possibly contaminated oil supply tank?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Dec , 2019, 20:28
Hello Mr. Tore,

Also, is Cylinder. #1 next to the Maneuvering panel?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Dec , 2019, 00:59
Don, The GW crankcase was never designed to contain lubeoil (dry sump design) hence any contamination would drain into the system tank below the engine no valves except a selection valve case to select which systemtank to take the drain.. Originally the luboil sentrifuge could be connected to either system tanks, cleaning the oil, later a large filter substituted the oilseparator and to a certain extent handle limited amount of water, after a massintrusion of water the filter was not able to handle the contamination and we exchanged the luboil source. You are able to connect the lubeoil suction of one engine to the other systemtank by the emergency electrically driven luboilpump.
We named the cylinder next to the maneuvering stand no 1, I guess the Germans did the opposite.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Dec , 2019, 20:57
Hello Mr. Tore,

Thank you for the info... I sent you an email with one page attached. Would you please look it over and let me know if it looks OK. I'm going to give myself a Christmas present and have the book printed at a local shop to insert into my leather covered metal post binder. The cost for the print job is about $400 plus Georgia state tax (7.75%)...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2019, 02:21
Don you are certainly going to give yourself an expensive xmas gift. I guess I better repeat my previous ( primitive) description of the exhaust system through the pressure hull and  silencer. As you see on the bad sketch below there are a lot of means to prevent waterintrusion via the main exhaust system. Primarily the outer (before the silencer) main exhaust valve (flap valve with a pneumatically driven rotating disc) which very often had a leakage due to carbon deposits on the seatings, this leakage entered the pressurehull to the group exhaustvalve (mechanically rotated flapvalve) with a leakage container before the valve, able to drain the water into the bilge. If further leakages occurred the waterintrusion continued to the exhaust manifold along the engine way below the exhaustvalves in the cylinderheads. The exhaustmanifold had ample drainage to the bilge. Hence a water intrusion via the engine exhaustvalves would only happen if the elaborate system of main exhaustvalves and massive drainage of the main exhaust system failed causing the leakage to rise up to the top of the mainengine and enter the cylindercover exhaust ducts. This did not happened frequently and flooding of the main engines was a rare event. Yet it could happened lets say once or twice a year.

The normal starting procedure is always to "blow trough" as we called it (mainly running the engine by starting air with open indicator cocks without fuel) prior to a normal upstart. Blowing out the waterintrusion by starting air is as mentioned previously  risky.
I am impressed by your stamina on the Skizzenbuch and shall revert with further comments, if any later.
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2019, 02:44
Don.
I had some problem with enclosing my bad quality images, here is another  bad sketch of the group exhaustvalve with drainage.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Dec , 2019, 02:47

Hello Mr. Tore,


If the blow through was risky...

The normal starting procedure is always to "blow trough" as we called it (mainly running the engine by starting air with open indicator cocks without fuel) prior to a normal upstart. Blowing out the waterintrusion by starting air is as mentioned previously  risky.



Then would you manually crank the engine? Do I need to correct/change the page that I sent to you?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2019, 02:55

Don I guess you should modify some of the wording, I `ll revert a bit later ( have to attend a funeral).
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Dec , 2019, 03:01
My condolences...
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Dec , 2019, 10:55
Don. In your paragraph: " during a Dive, you state " If the main group exhaustvalve grindingprocess did not form a perfect seal......  you may say: in the rare event of not having a successful grinding of the group exhaustvalve causing a major waterintusion exceeding the draining capacity of the inboard main exhaustvalve and the engine exhaust manifold to be flooded, water might enter the main engine via the exhaustvalves in the cylinderheads.....
You may of course  use your native language to the express the meaning, but avoid leaving an impression that this was a normal event. Although an unsuccessful grinding was quite common it was very seldom so bad that it resulted flooding the main engine, the internal drainage could usually handle the leakage.
On the same page you state : after a dive you should never start the engine by air.... Normally you always start by air, but before starting after a dive with waterintrusion you should turn the engine manually with open indicatorcocks before a normal starting, which means blowing starting air through the cylinders with open indicator cocks prior to shutting the cocks and run the engine by air before startingfuel is added. Turning the engine by hand for checking/draining the cylinders can be done immediately after a dive which is often done if water intrusion is observed.   It might be a bit complicated, but in many cases you want to be ready for exhaust blowing as soon as you surface and then you are usually preparing the engines for start before surfacing. As you are aware of the CO does not like to increase the internal over pressure so you are careful with using too much air in the starting preparation otherwise  the CO might be ejected through the tower hatch when he enters the bridge.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Dec , 2019, 17:19
Hello Mr. Tore,

After translating the German and Japanese "Lubricator" documents, I have come to the conclusion that this devise only serves one purpose; to lubricate the cylinder sleeve and the piston rings. It has nothing to do with lube oil emulsification or sulfuric acid in the combustion chamber of the Diesel engine. I have attached the diagram from the German lubricator and translated the title;"Central Oil System Grutzner EZ up to 150 Bar with Rocker Arm Drive"... Now, doesn't that look and sound familiar?
<first drawing attached>

The Japanese document discussed the process of adding the ports to the Piston Sleeve...

The parts to be replaced during remodeling work are indicated by. When installing the MPL system, the cylinder liner must be grooved, but construction can be done without removing the piston with a dedicated tool. (B & W. UFC Type)

● Lubrication timing and range_____________________________________________________
<second drawing attached>
MPL has the same mechanism as the conventional mechanical type and achieves "low cost" and "equivalent oiling rate" compared to the electronic control type.

It looks like they inject Lub oil in both sides of the piston sleeve to lubricate the piston rings in contact with the piston sleeve; reducing friction and heat to preserve and prolong the life of the diesel engine.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2019, 00:32
The cylinderlubrication on the GW engines is done by the piston ring arrangement as a trunkpiston engine usually would be susceptible to too much luboil drawn from the crankcase up into the cylinder causing the luboil to take part in the combustion prosess fouling up the engine and increasing the luboil consumption. The piston skirt on a trunk engine is an elongation of the piston for a proper distribution of the sideforces, the cylinderliner lower part of a trunk engine gets in contact with the oilsplash in the crankcase, sticking to the cylinderliner and is drawn up to the combustion chamber. This could lead to building up carbon in the cylinder, hence you rather fit a piston scraper ring than a cylinder lubrication point in the liner.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2019, 01:07
Don I guess your latest addition on the lubricator (cylinder lubrication of the GW engine) could be omitted.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Dec , 2019, 01:33
Hello Mr. Tore,
Then what does the lubricator do?
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2019, 03:01
Don.

You may say the GW engine is an oldfashioned engine in many ways and the point lubrication was not perfect, you still needed a greaser with an oil can. The " fillingstation" for the oilcan is on the front bulkhead  stb side you`ll find it on the luboilsystem plate. A point lubrication oil tank fills the greasers oilcan manually. The lubricator is an attempt to improve the  manual greaser by leading small pipes to difficult accessible lubrication points. Below are a few images showing what I try to explain. First of all I don`t remember all the lubrication points on the top of the engines, but the rockeram fulcrums are manual lubrication points, and I have included an exhaustvalve cage with a valvestem which needs lubrication, the connection in the cylindercover to the lubricator is assumed by me as the valvecage image is not from a GW engine. On the modern diesels the top with all the valves are covered by a so called dustcover and the oil is splashing all over eleminating the greaser.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2019, 03:20
Don further to my todays post here is the plate showing the greasers " can filling station."
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Dec , 2019, 08:21
Don I had a quick look at the specification for the  m/y Haida ...you mentioned. the engines are installed in 1929, no mentioning if they are four stroke trunkengines or bore/stroke. However they are mentioning one damage due to a chromium plated cylinderliner, chromium plated cylinderliners use to be for two stroke crosshead engines. The Krupp Germaniawerft made submarine- and yacht diesel engines and the image of the lubricator looks similar to the lubricator on the VIIc type. What make me suspicious as a possible reference for cylinderlubrication need, is the Krupp engine specification, cast iron piston and chromium plated cylinderliner which cannot be compared with the GW engine having light alloy piston and cast iron cylinerliner. Most four stroke trunk dieselengines to day have not cylinder lubrication. I can`t remember any on U 995 but failing memories exsists.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Dec , 2019, 05:19
Hello Mr. Tore,


A little research... GM built the US Navy sub engines and I have attached the Piston design. It looks like the cylinder liner is lubricated from the piston. Oil exits the piston crown and is captured below the compression rings and exits at the out the Lub control rings into the oil sump.


Do you have any drawings of the GW engines pistons?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Dec , 2019, 05:54
Don. your image shows a light alloy trunkpiston with internal coolingribs inside the piston crown. The lubricating oil is forced up in the bore of the piston rod from the mainbearing and is squirting out from the gudgeon pin bearing towards the cooling ribs in the piston crown. This system is a combination of a bearinglubrication and a cooling of the piston by the luboil. The oil is collected in a cooling chamber in contact with the pistoncrown, the coolingchamber have a direct natural free drain down to the crankcase and do not take direct part in the lubrication.  What is interesting however is that the image shows the lower pistonringpacket named as oilcontrol rings with drain borings in the piston skirt. The drain goes from the ringgrove in the pistonskirt  (not on the surface) and down thus do not take part in lubrication of the cylinderliner but leaving the piston inside the pistonskirt wall to the crankcase, this confirms that you rather scrape down the luboil in the lower part of the cylinder liner to control the luboil consumption (preventing to draw the luboil up into the combustion chamber.)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Dec , 2019, 06:40
Don.  Below is a cross section of the GW engine, the piston is an uncooled trunkpiston of light alloy. 400 mm dia. As you see from the cross sectiondrawing there are no cylinderlubricating points. On the lower part of the pistonskirt is an oilcontrol ringpacket consisting of scraper rings which control the upward luboilflow by scraping the oil downwards. From the scrapering piston groove there are drain bores going to the internal piston skirt letting the oil to be drained down into the crankcase and systemtanks.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Dec , 2019, 06:53

Don I just had a look at U-Historias image of the GW mainengine front nearly a same image as below. U- historias image marks my assumed exhaustvalve lubrication point as no 14 saying this is " tubo de engrase valvula" I am not very conversant with the spanish language but I assume U Historia is of the same opinion as me. May be we can draw a conclusion.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Dec , 2019, 14:55
Hello Mr. Tore,

I translated the u-history.com comment to "grease tube valve"... "Google Translate" looks to do a good job translating many languages and the source/destination language has many different combinations.

It looks like the GW Piston has no internal lube oil cooling ability. However, the GW piston has 7 compression rings and 2 lower oil control rings. Where the American GM piston design only has 4 compression rings and 2 lower oil control rings. Interesting....?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Dec , 2019, 23:05
Hello Mr Tore,

I FOUND IT!!! U-Boat Archive Series Volume 7, Report on U-570 - H.M.S. Graph - Page 70

Main Engine Liner

"Cylinder lubrication is by means of a Grutzner pump with tow connections to each liner, inboard and outboard. There are no oil groves cut in the liner walls and no holes are provided for piston slinging gear."

Main Engine Pistons

"They are fitted with 6 impulse rings, 1 upper scraper ring and 2 slotted scraper rings, Drain holes are drilled behind the 2 lower scraper rings and also in the oil catchment groves. The groves, 2 in number are situated immediately below each slotted scraper ring."

Don - Therefore, it looks like pump connection is situated so that the nozzle will always be in between the 7 top piston rings (compression rings) and the 2 lower scraper rings (oil control rings).

Exhaust and Induction Valves - Page 72

"The stems of both exhaust and induction valves are lubricated by a mechanical pump driven from a camshaft'"

Connecting Rods - Page 71

"The connecting rod has a large diameter bore through it, being reduced near the eye of the rod. The lubricating oil is taken round the gudgeon and fed through the pin through 4 holes at 45 degrees above and below horizontal."

The only thing that I'm not sure of is how are the rocker arms lubricated, Is the above describing how the rocker arm pivot point is being lubricated...? ???

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2019, 00:41
Don U-570 ex HMS Graph  was a VIIC built by Blohm & Voss and the main engines were MAN m6v 40 46 type being turbocharged and a different construction than the GW engines. Although they did the same job. The MAN design was a bit more "advanced" than the GW engine  but the latter was considered to be more reliable.  Sorry I don`t think we can compare the details of the GW engines with the MAN.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Dec , 2019, 00:53
Page 64 - two sets of GW 4-cycle engines built by Blohm & Voss under Krupp License at Hamburg...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Dec , 2019, 02:20

Don
You are absolutely right, U 570 was equipped with GW engines, I did not checked the British report but the US report of september 28th 1941, classified reliable, and made by 3 US naval officers who was onboard inspecting the submarine U570  23.- 26. september 1941 at Hvalfjordur Iceland. Obviously not very reliable as they say on page 51 section II-C-  2 :" Main engines   The two 6 cylinder, 4 cycle, solid injection M.A.N engines are rated at 1400 horsepower each at 470 rpm with supercharger cut in........" I should of course had been a bit suspicious on the cut in expression. But in a hurry I just noted the MAN. So much for reliable source, sorry Don. I guess we possibly could accept the cylinder lubrication by the GRUETZER lubricator and leave the in lubrication of the fulcrums to the manual greaser I am a bit bewildered on the valvestem lubricator driven by the camshaft.  For easy access to the fulcrum lubrication  on the top a foldable step was arranged along the engine. as shown on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 13 Dec , 2019, 08:12

Ahem...


https://models.rokket.biz/index.php?action=dlattach;topic=1621.0;attach=11906



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Dec , 2019, 22:37
Hello Mr. Tore,

The GW Diesel engine design had no top valve cover... Was there any maintenance procedure where the push rods and valve rocker arms which were exposed to the engine room were lubricated? Were there any grease nipples located on the GW Diesel engine?

I have attached 2 charts:
<1st chart is the GW Diesel engine crank shaft and ignition timing>
<2nd chart is the Lubricator injection and the GW Diesel engine stroke timing>

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Dec , 2019, 03:43
Don, I don`t think we had any fixed lubrication instructions for the many fulcrums and contact points on the top of the engines. As mentioned the technology was pretty much based on pre WW2 practise and local manual lubrication was the custom. I guess you are able to see the lubrication points on the tops of the valve rocker arm on the enclosed image below. There were no greasecups on this point as far as I remember an oildrop was added at regular intervalls to the engineer/greasers judgement. The manual point lubrication was an important time consuming part of the engine crews watch. To day I am afraid that many layers of fancy paintings are hiding the many lubricating points on the top.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2019, 14:32
Hello Mr.  Tore,


The attached photo looks to have captured the lube point for the valve rocker arm...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Dec , 2019, 01:37

Don. I am afraid it might be a bit more complicated than indicated on your image. I guess your yellow arrow is pointing at the setscrew (locking) for the pedestal shaft and thus fixed to the pedestal. The rockerarm is pivoting on this fixed shaft and hence need lubrication which is admitted via a wart on the rocker arm. Usually the fulcrum shaft is locked and the arms are pivoting. The shafts are usually locked in the support either by segerings or setscrews, the latter can easy be mistaken for a lubrication wart as the threaded boring is in a wart similar to the luboil bore. My image below explain what I mean.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Dec , 2019, 17:16
Hello Mr. Tore,


New terminology for me... "Lubrication Wart" is this a raised circular area with a hole in the center going down to a shaft that needs lubrication? Since these are rocker arms, would you use grease rather than lube oil because of the constant up and down motion that may sling a lube oil out of the "Wart." Or, does the Wart have a cover?


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Dec , 2019, 00:55

Don.
 I guess warts on engineparts is not proper english for the extra materials needed for bores with or without threads primarily on cast steel /iron. Not always used for lubrication, but bores for setscrew, drainplugs etc. Grease need pressure to get to the lubricating points hence mostly luboil is used. Proper lubrication of a dieselengine having an open top was difficult before the topcover was introduced. The time consuming pointlubrication  was one thing, another was the drains from all these points which you didn`t like to get in to the bilges. Hence an elaborate system of funnel and small drainpipes was installed to take the drain from the top. The system was susceptible to damage especially during maintenance.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Dec , 2019, 14:53
Hello Mr. Tore,


I noticed that the Selector Valves for air distribution in the Diesel engine room were both painted red on U-995, even though they look to be on the port and starboard side. Is red the original color for both valves? ???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Dec , 2019, 16:33
Hello Mr. Tore and All,

Merry Christmas and Happy New Year; Wishes for a Peaceful New Year and Lasting Friendship!

Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2019, 02:29
Hello Mr. Tore,


I noticed that the Selector Valves for air distribution in the Diesel engine room were both painted red on U-995, even though they look to be on the port and starboard side. Is red the original color for both valves? ???


Regards,
Don_
Don. On the museums U 995 they have not tried to conserve the original colours and it is hard to see the system of colours ( if any). Do not use the red painted valves, cocks, grease cups, gauges etc. as a reference. They have evidently left it to the painter to chose the colour he prefers, to me it looks more like an amusement park than the interior of a WW2 VIIC.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Dec , 2019, 03:39
To all the VIIC entusiasts!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 23 Dec , 2019, 11:32
Thank you Tore! Much appreciated. Best Christmas wishes to you too and a thousand THANKS for your incredible contribution to the Forum. Something that has become more and more Mythologic over the years.
Merry Christmas!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 23 Dec , 2019, 23:04

Merry Christmas to all also from me ... Santa Claus brought me the best gift you can receive: a new love .... after a long time, the smile returned to my lips, the warmth in my heart ... who knows that the desire to approach modeling will not come back to me again ...
Best wishes to all
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: bianco64squalo on 23 Dec , 2019, 23:05

Merry Christmas to all also from me ... Santa Claus brought me the best gift you can receive: a new love .... after a long time, the smile returned to my lips, the warmth in my heart ... who knows that the desire to approach modeling will not come back to me again ...
Best wishes to all !!!!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 24 Dec , 2019, 03:48
Hello all,

Merry Christmas to all. Hope you get time at the modelling table over the festive break.

Cheers,

Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 26 Dec , 2019, 08:04

I'm a bit late but I hope everyone had a blessed Christmas and here's to a happy and prosperous New Year.


Filippo, that is wonderful news. Love is the best gift of all.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jan , 2020, 01:38
Hello Mr. Tore,

I was reviewing some of the photos that I have collected over the years. Does this photo taken below deck look to be the Knife Oil Filter (page 153) that was added after the Oil Purifier was removed?

<see attached image>

Regards,
Don_

PS - It looks like there have been 400 downloads of Skizzenbuch from the Subcommittee.com website.

Personally - I had a heart attack Christmas Eve and spent 4 days in the hospital and they installed a stent in my right artery. Later, they may do Robotic Surgery and bypass a couple partial blockages in my left artery. My heart plumbing is beginning to look more like a U-Boat lube oil diagram!
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2020, 02:46
Don, sorry to hear about your heart issue, If your heartplumbing looks like a plate 13 coolingwatersystem don`t forget there is an anti corrosion connection to be used regulary to prevent further damage.
As to your posted image I guess you are showing a gatevalve (sluicevalve). As can be seen on my image below there are 5 gatevalves in the coolingwater crossoverpipe and I guess your image shows one of the 3 centervalves. Gatevalves are free flood valves and used in places where you want as little resistance as possible, however the valve housing needs a lot of space and might resemble a filtercasing.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Jan , 2020, 03:01
Don, Both lubeoilfilters are pretty close and before the coolers as can be seen on my (Simons ) image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 02 Jan , 2020, 08:02
Jeez Don, hope you're doing ok. What a great Christmas gift. Glad you have a sense of humor about it. Congrats on the book too.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jan , 2020, 11:52
Hello Mr. Tore,

Reviewing Simon's piping drawing:
1.  It looks like the 2 lube oil filters near the oil coolers are the strainer type filters which have always been in place.
2.  The six (6) valves a, a1, and b on the valve chest look to be clustered in the center of the drawing.
3.  What is the device at 8 o'clock (lower strainer) and 10 o'clock (upper strainer)?
4.  The port and starboard water supply valves don't look to be air activated weed clearing?

<image attached>

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2020, 13:49

Don, I am sorry in a hurry I posted the normal Plate 14 luboilsystem which shows the old execution with the luboil strainer. I don`t have any scheme showing the new luboilfilters in place but assume we once figured out they would be placed as indicated on Simons image. I am not 100% sure that Simons image is his final and I should have mentioned that as well. I don`t think you should use same in your Skizzenbuch. The weedblowing system is indicated on the well known plate 13 coolingwater crossover pipe intakes, but the pasting on the port side was not complete and hence omitted. In fact I guess i should not have posted the lubeoil system as my answere was on the image of the gatevalves in the crossover sea coolingwater pipe.
Sorry by the confusion I created, you cannot use the plate 13 to show the later version of the systems. Evidently sometimes things goes to fast for a 91 year old man.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jan , 2020, 14:11
Don. Sorry I missed your question on some items indicated on the luboil strainers, I am not sure I got your question right, but I guess you are referring to the manometer showing the pressuredrop over the strainer.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Jan , 2020, 18:53
Hello Mr. Tore,

You are a very sharp dude at 91... I have attached Simon's drawing and I have labeled as to what I believe are the Strainer Filters and the Knife Filters. The schematic does not include the Knife Filters as expected, but it looks like Simon's drawing does so...

Don't play that "Old Dude Card" on me! You out lived Maciek, and you could possibly out live me as well and be the last man standing!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 07 Jan , 2020, 08:17

I have a question regarding the Aux cooling Water Pump location. I cannot seem to find any photos of the forward Stbd bulkhead area and I'm trying to figure out exactly where the pump is located. Is it completely under the deck plates? Looking at Simon's drawings it appears to be a vertical pump, slightly smaller than the Aux LO Pump.


I can't determine the elevation of the pump. I need to scratchbuild one which isn't that difficult. I just need to know where the heck it goes.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Jan , 2020, 13:53
Katuna.
no wonder, I don`t  have a photo of the pump but I guess you are able to see a small part of it under the writing plate, quite near the valve-chest on stb. side. I guess the pump has a bulkhead bracket to be fixed to the fore bulkhead, just beneath the floorplate. On my image you see the double sea inlet valve for the crossover pipe, might be an indication of the location. It is indeed a very narrow area and sharp pipebends.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jan , 2020, 14:22
A little better view....
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 07 Jan , 2020, 15:39
Thank you both so very much! I have anguished over that pump for ages. Well, maybe anguished is a little overly dramatic but nonetheless, it has puzzled me for some time. Thanks again gentlemen.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2020, 02:39
Katuna I have taken one of Simons images of the coolingwater system, I am not sure he consider same final but superimposed my idea of the bulkhead mounted aux. coolingwaterpump
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2020, 03:21
About 10 years after the Norwegians decided to hand over KNM Kaura ex. U 995 they started the restauration of the tower from the Norwegian design to the orginal German design. Here is an image of the start of the tower restauration prior to the hand over ceremony november 1971.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 09 Jan , 2020, 07:50

Tore - Thank you very much. That plate drawing is much easier to see too.


What were the main changes the Norwegian Navy made to the tower when they took possession after the war?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2020, 08:24
Katuna.
As we didn`t need the heavy AA guns we dismantled the wintergarten as can be seen on my image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Jan , 2020, 08:38
Katuna.
A more modern version of the tower was the sail as shown on the image of knm Kya ex. U 926 below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Jan , 2020, 20:36
Hello Mr. Tore,

The photo of the modernized Kya reveals a clear wind screen at the front of the bridge/tower sail. Was it a fold down type or permanently in place. There also looks to be an extension tube to the aerial periscope. Did they switch from using the attack periscope while schnorchelling to the aerial periscope because of the larger head optics?

This would mean that they extender the length of the aerial periscope to place it near the schnorchel head... That would eliminate the issue with the exhaust gases in front of the attach periscope causing vision problems.

<See attached drawing>

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Jan , 2020, 01:02

Don.
The modernizing of our VIICs was an element of research in our plans for renewing/upgrading our submarine fleet. Although I was the chief engineer of KNM Kya ex. U 926 in 1954 I was not involved in this work, but knew the designer very well. I am sorry I don`t know the details. It was only modernized one of our VIICs, KNM Kya, as shown on the image. The conclusion of the research was it is better ( and less expensive) to build new submarines rather than converting the old VIICs hence we contracted 15 new  submarines ( a new class) in Germany. Time had passed and changed,  the situation was different and WW2 was remote and the VIICs were due for the museum.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2020, 01:37
Hello Mr. Tore,

U-926 became KNM Kya (S307) and served until 1962, and the submarine was scrapped in 1964. Using the reshaped bridge style of the Walther U-Boats, instead of the usual VII C bridge (Minus the wintergarden, the AA platform behind the bridge and the armaments), only an insignificant increase in speed resulted, but depth keeping properties were greatly improved. The final Kya bridge/tower conversion was very modest <attached photo> compared to the original proposed Walther bridge style renovation. The bridge sail had a notch on the port side where the un-modified schnorchel raised from the unchanged bed in the wooden deck structure.

Don's Note - Because of the increased height to the aerial periscope tube casing, it looks like they extended the length of the aerial periscope to just above the schnorchel mast head for better observation while scheorchelling. This accomplished two benefits: the aerial periscope had a larger optics head and tilted for better observation, and the placement of the attack periscope inback of the diesel exhaust vent created a vision problem at times.

It looks like the Norwegians put a lot of thought into the U-Boat Type VII C renovation project, and we have Mr. Tore to thank for preserving these photos from the past.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jan , 2020, 18:25
Hello Mr. Tore and All,

Here are the attached photos of the only known printed version of Skizzenbuch. The metal covered leather post binder and the 11 x 17 inch 80 pound card stock paper and the printing cost came to about $690.00. This was my Christmas present to me!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jan , 2020, 18:27
More images...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jan , 2020, 00:50
Don.

Fantastic, some xmas present, but you deserve it, having the stamina to fulfil the collection of informations which makes the complete Skizzenbuch. It is of course an expensive task to print one of the kind book, but it must be a collectors item. Mission accomplished, congratulation!!
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 14 Jan , 2020, 07:35

Wow Don, what a fantastic book. I wish it were financially viable to put it into print. At $700 a pop, it's just a bit out of my price range (at least if I still want to sleep inside my house!) but a soft back coffee table version would be wonderful. Too bad it's such a limited market. If you could get a version down to $100 I bet you could sell a few at Laboe.


Congratulations on such a beautiful end to a long project.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jan , 2020, 20:05
Hello Mr. Tore and All,


Thank you all for your approval of my printed Skizzenbuch. However, I just added one page to the front of the book just after the paisley cover page. It is an autographed photo of Oberleutnant zur See Hans-Georg Hess who was the last German Commander of U-995 during WWII.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 15 Jan , 2020, 11:04
Congratulation Don! It 's been a titanic effort but what a reward! Thank you for that. i hope to be able to buy a copy someday. Enjoy the taste of victory now   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Jan , 2020, 19:11
Hello Mr. Tore and All,


I provided the www.Wehrmacht-Awards.com/Kreigsmarine War and Qualification Badges/  website with a download of Skizzenbuch and it looks like there will be more than 240 downloads within a week and their members are worldwide... I have been a member for several years and there experts helped me to determine if some of my badges and Iron Crosses were original or reproductions...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 24 Jan , 2020, 14:11
Congratulations Don.
Fyi.
I also promoted the download on multiple Facebook U-boat sites.
From the comments a lot of members downloaded and enjoyed it. Thanks
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Feb , 2020, 15:24
Hello Mr. Tore and All,

Here are the attached photos of the only known printed version of Skizzenbuch. The metal covered leather post binder and the 11 x 17 inch 80 pound card stock paper and the printing cost came to about $690.00. This was my Christmas present to me!

Regards,
Don_
Hi Don, The metal covered leather post binder look beautiful! Would be keen to do something like that for my book, where did you get it done?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Feb , 2020, 15:27
Hello Mr. Tore,

The photo of the modernized Kya reveals a clear wind screen at the front of the bridge/tower sail. Was it a fold down type or permanently in place. There also looks to be an extension tube to the aerial periscope. Did they switch from using the attack periscope while schnorchelling to the aerial periscope because of the larger head optics?

This would mean that they extender the length of the aerial periscope to place it near the schnorchel head... That would eliminate the issue with the exhaust gases in front of the attach periscope causing vision problems.

<See attached drawing>

Regards,
Don_
Not sure if this is helpful but the aerial periscope on U-995 is not for a Type VIIC its from a Type XXIII.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Feb , 2020, 19:24
Hi Simon,

The post binder came from:

http://www.spectra-associates.com/postbinders/postbinders.html (http://www.spectra-associates.com/postbinders/postbinders.html)

They will do embossed printing on the binder as well... The binder has a small hole in the binding end where you insert a key. You turn the key several turns which moves a locking slide to open the binder. They have end covers to match the binder and the post comes at a standard length and you add extensions to increase the binder width. Also, I believe the posts come in 2 diameters 5/16 and 3/8 of an inch. Here is my order# 34154-F to see my complete order...

I thought the aerial periscope top half was just another Type VII C attack periscope?

<see attached photos>

Do you have additional info?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Feb , 2020, 06:38

Don and Simon. It seems to me that they have removed the aerial or navigation periscope on the museum U-995 and possibly substituted with an attack periscope for some reason. Below are a few images showing the original aerial, navigation periscope from my time onboard. The other image shows the last German CO Hess during a visit end 1990 looking into the aerial , navigation periscope, currently installed and clearly a different type. The last image shows U-995 returning from her last patrol in the Barentz sea march 1945 to Trondheim to have her Schnorchel installed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 03 Feb , 2020, 17:10

Don and Simon. It seems to me that they have removed the aerial or navigation periscope on the museum U-995 and possibly substituted with an attack periscope for some reason. Below are a few images showing the original aerial, navigation periscope from my time onboard. The other image shows the last German CO Hess during a visit end 1990 looking into the aerial , navigation periscope, currently installed and clearly a different type. The last image shows U-995 returning from her last patrol in the Barentz sea march 1945 to Trondheim to have her Schnorchel installed.
Tore

Yes, in the first photo you can cleanly see the Type VII navigation periscope and they changed it to a Type XXIII attach periscope. Maybe the old periscope was damage :-\
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Feb , 2020, 22:01
Hi Simon,


Do you have any documentation or photos that will verify it is a Type XXIII periscope? It looks like the forward periscope optical tube has a much smaller diameter than the original Type VII C Aerial Periscope optical tube...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Feb , 2020, 23:27
Hello Mr. Tore and Simon,

It looks like Simon is correct about U-995 aerial periscope being replaced with a Type XXIII attack periscope...

1st image from <U-995>

2nd and 3rd image - U-2367 (S171 U-Hecht) Captain-Lieutenant Bringevat stands at the periscope on the submarine Hecht. On the submarines of the XXIII series a periscope of 7.5 m in length was installed, its stroke was 4.16 m. It could be used for day and night attacks. Small changes in depth made the commander often change his posture (to engage in "periscope squatting").

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Feb , 2020, 03:54
Don and Simon.
Below an image showing the difficult position of an aerial/navigation periscope squatting, the other showing the comfortable sitting and turning the attack periscope by footpedals.
I am not sure, but we had one type XXIII submarine in our fleet KNM Knerten, ex U-4706 having an unfortunate career of battery explosion and was never commissioned. It could be the periscope was donated to the germans at the time of handing over the U 995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Feb , 2020, 13:31
Hi Simon,


Do you have any documentation or photos that will verify it is a Type XXIII periscope? It looks like the forward periscope optical tube has a much smaller diameter than the original Type VII C Aerial Periscope optical tube...


Regards,
Don_
When Maciek and I were working on the periscope project we realise it was the wrong periscope. 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Feb , 2020, 00:01
Hello Mr. Tore and Simon,

Do we have any idea as to what happened to the original U-995 aerial periscope?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 05 Feb , 2020, 17:04
Fyi
You could also ask that question as well on the curators Facebook site if no one is sure.

Freundeskreis U995

http://Https://m.facebook.com/pages/category/Monument/Freundeskreis-U995 (http://Https://m.facebook.com/pages/category/Monument/Freundeskreis-U995-833633730175464/)


Fyi. I cant seem to get this link to work but just search Freundeskreis U995 on FB.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 05 Feb , 2020, 22:24
Hello Mr. Tore and Simon,

Do we have any idea as to what happened to the original U-995 aerial periscope?

Regards,
Don_

I will check my old email from Maciek and see if I can found anything.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Feb , 2020, 00:26
Don I don`t know but they did a lot on the KNM Kaura ex. U-995 after my time. If the original existing aerial/ navigation periscope was ok it could of course be a spare one for the other VIICs in operation. Such equipment wasn`t easy to get just after the war. In the end of 1950 we were looking for solution of renewing our submarine fleet and as an alternative we looked at modernizing the VIICs which turned out to be very complicated and expensive to that of building new ones from scratch, thus I guess the original periscope possibly was used as spare for KNM Kinn and KNM Kya. KNM Kaura at that time was operated as a training submarine.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Mar , 2020, 16:25
Hello Mr. Tore, Simon, and Mark,

To date it looks like there have been well over 1,400 downloads (Subcommittee.com,WehrmachtAwards.com, and numbers unknown from the AMP website) of Skizzenbuch; I am very grateful for all of your assistance in the project. Also there looks to be websites in the UK, China and Russia who are distributing Skizzenbuch with a slow 5 1/2 hour download speed, or a 4 minute download speed for $7.95 to $89.95 (They also distribute many other Copyrighted books; most likely ***Pirated***).

I have been working on an Addendum Booklet for Skizzenbuck to post corrections, and I have had input from one reader where I corrected 2 Type-o's in Skizzenbuch on page 479 in a drawing which could not be checked in Word. These type-o's will be in the CD that I sent to you all (Sorry about that)! If you all have any suggestions for the Addendum Booklet, or corrections for Skizzenbuch, then please let me know...

My time has become more available and relaxed (I still have an upcoming stress test after my heart attack and possible Robotic Bypass). I have restarted working on "Skizzenbuch: U-Boat Type IX C Project" and have a rough draft of about the first 100 pages... Any input would be highly appreciated, and I plan on posting conversations on this forum...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Mar , 2020, 05:57
Hello Mr. Tore,

Additional research...

The Norwegian Navy got U-4706 Knerten a Type XXIII U-Boat in October 1948, and in April 1950 transferred/used by the Royal Norwegian Yacht Club for storage. She was stricken in 1954 and broken up. This is possibly where the Type XXIII Attack Periscope came from that was installed into U-995 Kaura. So possibly, U-995's Aerial Periscope was damaged while used for training and it got replaced with what was available at that time.

What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Mar , 2020, 17:05
Hello Mr. Tore,


Are all the images in this photo of U-995?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 19 Mar , 2020, 01:44

Don.
The two upper (bad) photos are originals of KNM Kaura ex U995 taken by me during annual drydocking in 1953. The lower photo is details of assumed zinkanodes on my model of KNM Kaura. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Mar , 2020, 03:21
Hello Mr. Tore and Simon,

I was wondering why we have not seen zinc anode plates attached to the protective structures ahead of the bow hydroplanes. I've seen images where the forward protective structure has eroded away/gone from the aft tip (bow) extension where the hydroplane actually pivoted in the structure.

"Iron is also the most corrosion-prone material when it comes in contact with air and water. A ship is continuously in contact with water and moisture-laden winds which makes it highly susceptible to corrosion. The outer body of the ship (mainly hull) is continuously in contact with water, making it extremely vulnerable to corrosion. It is for this reason sacrificial anodes are used to protect the parent material."

The above article talks about winds and the anodes are in the aft section with a huge propeller. Does the prop create the moisture winds which induce the corrosion - electrolyses process and thus requiring the zinc anode plates?

It looks like the zinc anode plates were only used to protect the aft hydroplanes, rudders, and the support structures. Also, none on the hull or the bridge, and I have seen quite a few photos of the bridges just rusting away... Were the U-Boats not believed to survive the war long enough for rust/corrosion to be a problem?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 27 Mar , 2020, 08:59
Don.
The stern of a VIIC has a great numbers of materials with different potentials which might cause heavy corrosions if not protected. The idea of zink anodes is that you protect all these different materials by introducing a sacrifice anode protecting all these different alloys, hence Zink is used for anodes. The anodes are placed for an optimal protection for the various materials, at hydroplanes, rudders, A-brackets and propellers. In order to have an optimal contact, the zink should be fixed to the item to be protected by ensuring the best possible metallicsurface contact hence bolted, or tack welded to a steel strap casted in the zinkanode,  no paintings on the surfaces. In addition to galvanic corrosion the area suffered cavitation corrosion primarily pittings on the propeller blade roots, caused by bad propeller flow. The bad flow created small vacuum bubbles rapidly filled with steam. The eventual implosion of the vapour bubbles caused noise and the implosions extracted small cavities in the propeller material.   Galvanic corrosion can create substantial damage at strange places, hence placing of the protecting anodes might vary substantially and same are sometimes placed according to experience. F.i. when a standard propeller of special metal alloy is changed by a cast steel propeller, the placing of the zink anodes would possibly have to be changed, hence you would have a number of anode locations on various VIICs.

Finally if you have a closer look at the old U 995 you shall see  deep corrosions in the pressurehull. Some modelbuilders have taken great effort in copying same. These are galvanic corrosions due to negligent of maintenance and possibly  hostile environment (pollution) for years. With such a pressurehull the U-995 would not be fit for a frontline submarine during the war.

In my time we used Zinc chromate a yellow painting as a anti corrosion painting and not zinc anodes in the ballasttanks etc.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Mar , 2020, 18:59
Hello Mr. Tore,


Has the COVID-19 Virus shutdown Norway like the rest of the world? Maureen and I, just went grocery shopping and most food items have been restocked, but paper towels, toilet paper, and sanitation products are not available as of yet. How about your location...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Mar , 2020, 23:14
Don.  We are indeed shut down, As my oldest son was traveling in Kenya we were kept busy getting him home, he is now in quarantine for a couple of weeks, we are in quarantine, voluntary in our home, as we are classified as belonging to a risky group, mainly because of age. In all, this country was reasonably well prepared so we have currently a low deathrate, only 20 in a population of 7 million. I never understood the great demand for toilet paper during crises like this. We order all our groceries by phone and get it outside our door, we dont`t even see the delivery guy. Good old U 995 KNM Kaura would be the place to be right now.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 31 Mar , 2020, 13:42
Hello Mr. Tore,

I have attached four (4) photos of the Bow Ice Shield which is used to protect the torpedo tubes in Winter Arctic waters when iced over. It looks like they could release the three (3) front cables and use the last cable to retain the shield. It looks like the last cable uses the bow cleats near the deck edge and the bollards to hold the cables and retain the shield. However, this is just a guess on my part and I can not seem to find and description/data just these photos on the internet...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2020, 00:55

Don, Simon, Dougie47 and others.
 In my time we operated from the German built submarine pens in Trondheim. The pens were primarily built for submarine operation towards the convoys heading for Murmansk. We mainly used one of the 2 pens and the access to the pen was normally covered with ice during the winters. I never saw anything like the bow ice protection shown on your images, neither in the stores, nor in the workshops. We had continuously a small tug/icebreaker keeping the access open. I can not imagine they used this cumbersome rattling devises on their frontline submarines, I should imagine this was, as previously said, probably used for training boats operating out of northern German harbours. Below an image showing the normal winter condition in Trondheim, I guess you are able to see the small harbour tug/icebreaker as well as KNM Kaura ex U 995 entering the pen after returning fra an artic mission in winter 1953. Normally the open waters north of  North cape and Murmansk were ice free except a few narrows and harbours.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Apr , 2020, 02:37
Don, Simon,Dougie47 and others.
Come to think about it. There were special missions like erecting automatic weather stations for submarines  frequently in the icy waters of artic like, Canada, Greenland and Spitsbergen, IX boats were used and might have been fitted with Iceshields. The boats were to my knowledge stripped for torpedoes and might have needed som ice protection when landing the equipment.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Apr , 2020, 15:50
Hello Mr. Tore and All,

Attached is a photo from the book "U-BOATS: The Illustrated History of the Raiders of the Deep" by David Miller. The photo Showa a U-Boat Type IXC equipped with an Ice Shield as what Mr. Tore described in the previous posting.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Apr , 2020, 03:55
Hello Mr. Tore and All,

Really nice artwork...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 07 Apr , 2020, 07:45
Don I found another pic of the icebreaker, a frontal closeup. Boat is U 48. hope this helps


http://cubeupload.com/im/SGm/U48Icebrkr.jpg (http://cubeupload.com/im/SGm/U48Icebrkr.jpg)


Cheers,
SG





Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2020, 23:16
Hello SG,


Thank you, that was like one of the photos that Dougie Martindale emailed to me...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Apr , 2020, 23:26
Hello Mr. Tore and All,

I have been working with Simon on the vent valve for MBT 1.  Back when I was working on FBT 2, MBT 3, and FBT 4, I discovered the U-570DTPlate28.jpg from the uboatarchive.net was drawn wrong by the Germans where the levers pulled down had the vents closed (WRONG!).

Today Simon noted that the drawing for the vent valve for MBT 1 would never function because the flap valve plate was on the outside of MBT 1. It must be on the inside of MBT 1 to be functional. This was also incorrect in the u-historia.com drawings that I got from them.

I corrected Skizzenbuch and here is the attached corrected drawing...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Apr , 2020, 01:15
Hello Mr. Tore and All,

During your service on U-995 and U-926 did you have an occasion to examine the construction of MBT 1; the rudder pedestal and the dual rudders? The question:

1. Is there a notch in the top of MBT 1 which allows the rudder pedestal's drive rods to control the dual rudders?
2. Is there a channel passing through MBT 1 which allows the pedestal's drive rods to control the dual rudders?

See the attached drawing... Do you have any images or better drawings?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 10 Apr , 2020, 10:52


Don.
Referring to the lower image. I guess the rudder drive goes through the pressurehull as shown between frame 3 and 4 to the yoke of the rudders situated in the void space in the freeflood area in the casing under the deck. From this yoke the two rudder rods goes in the freeflooded area to the yoke of each rudder, the two rudder stocks goes in two pipes down to each of the rudders. Thus primarily in the free flood area outside any tanks after leaving the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Apr , 2020, 00:35
Hello Mr. Tore,

I could not find an answer to my question about how the pedestal drive rods got to the dual rudders and through MBT 1 in the Type VII C diagrams. However, the Type VII D diagrams do show dual channels passing through MBT 1. In the diagram you can see the pedestal drive arms and the drive rods in the middle of the channels at Spt. -6 frame (See the attached drawing). Do my assumptions look to be correct?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Apr , 2020, 14:39
Hello Mr. Tore and All,

Let's hope for a Happy Easter and Passover; may the season of Spring renew and heal our world...

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Apr , 2020, 19:47
Hello Mr. Tore,


I found this photo of KNM Kya on the internet... I can see the Norwegian designed tower/winter garden.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Apr , 2020, 23:46

Don. I never saw the photo, but I am pretty sure it is from my time. I know the guy very well, both from the naval academy and later. I am probably on the bridge.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Apr , 2020, 21:50
Hello Mr. Tore,

I have a question about the drive shaft to open the vent valve for MBT 1... The hand wheel is located on the control room aft pressure hull on the Port side.

1. The 1st photo shows the diesel room with the MBT 1 drive shaft RED on the port side. The cream colored shaft with a RED hand wheel controls the MBT 2 aft vent valve on the starboard side (this shaft goes to a bevel device to activate the dual vent valves for MBT 2).

2. The 2nd photo shows the drive shaft for MBT 1 vent valve coming through the bulkhead on the starboard side.

I don't see any cross-over of the MBT 1 drive shaft in the diesel room??? Do you have a better photo?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2020, 07:06

Don.
 No wonder, it is hard to discover. Just aft of the fuel daytank, settlingtank, and fore of the pneumatic exhaustvalve grinding machine is a chaincasing containing a chaindrive of the rod from port to starboard. I have superimposed in red the item and if you look carefully at the image you might be able to see the cage.

Tore


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Apr , 2020, 07:15
Don. May be this image with less text makes the chaindrive easier to discover.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2020, 14:58
Hello Mr. Tore,

Thanks for resolving my MBT 1 vent valve drive rod issue! I don't believe we ever discussed the drive chain before, but again I never asked the question... You are the man!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Apr , 2020, 23:08
Hello Mr. Tore,

I was able to get a fairly good image for my Skizzenbuch "Addendum Booklet"...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 May , 2020, 20:16
Hello Mr. Tore,

What if U-995 was submerged and a depth charge attack resulted in the support A frame on the port side was completely broken and there is no support for the port drive shaft and propeller. And to make it more interesting, the starboard diesel engine has a damaged #1 cylinder liner and piston and you have no spares...

When you finally surface; you can't just row the U-Boat back to your home port.

1. You could pull the piston drive arm, disable the injection pump and run on the other 5 Cylinders, but the engine would be terribly out of balance.

2. Would you pull the piston rods for all cylinders in the block with the damaged piston and liner, and run on the other 3 cylinders which would be balanced on the crank shaft?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 May , 2020, 23:59
Don. May be the ultimate solution would be to rise the periscope, collect the bed clothes and make a sail. I am not sure  if the crew would sacrifice their bedclothes though. In that case I would try to run on 5 cylinders, charging the batteries and use the E-motors limping home. I don`t see the point in dismantling the other moving parts in the engines. When the propeller shaft is damaged go back to the ultimate solution.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 06 May , 2020, 01:44
 ;D ;D ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 May , 2020, 01:23
Hello Mr. Tore,

Perhaps they could use the port diesel to charge the batteries and run on the starboard e-motor. I believe that would be making the best of the situation with these conditions.

What do you think?

I'll need to search and see if I can find out how U-45 (in the photograph) made it back with the damaged port side...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 May , 2020, 07:55

Don, as long as you don`t use your image as a reference for the situation, yes.  Your image shows a damage which might involve a flooding of the E-room, with main motors and switchboard making same useless. Further a major intrusion of water in an end- compartment and MBT 1, approximately a total of  62m3 if filled and a trim moment of - 200.3 meter tonnes would create a dangerous situation which might require a compensation, which again might lead to a larger aft draft.
Tore


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2020, 02:48
Hello Mr. Tore,

The documentation only states U-46 (not U-45) was attacked with a/s bombs, one of which was a direct hit on the stern, blowing a large hole in the outer plates. One crewman killed. U-46 returner to Kiel 29.10 40.

It looks like about 3 months later, back into action...

12.2.41 Left for the North Atlantis, to operate between the Shetlands and the Faros. U-46 returned to base 4.3.41.

It looks like the starboard side was OK to get back to Kiel for repairs...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 22 May , 2020, 14:17
Hello Mr Tore
I hope you are keeping well.
Apologies if you have discussed this before but having served both on Type VIIc and a Type VIIc\41 you are in a unique position to answer my question.
As not many interior detailed pictures exist of Type VII/c we only have  U995 Type VIIc/41 Kaura to show us detailed interiors.


It is written that the /41 had a stronger hull had the same Engines but was made lighter by less heavy internal equipment to compensate.


Although U995 Kaura had slight Norwegian modifications (and all the present day colors are incorrect) can you advise what  major internal equipment was different on U995 from a Type VII/c.


Both the subs you served on were middle to late war. U926 and U995


For example a major internal change on the Type VIIc was the Electrical Switchboard going from a an Early war Round Type U552 to a Rectangular Type as seen in U995.


Thank you. Stay safe.


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 May , 2020, 09:13
Raymic1

Thank you for the good wishes, going on 92 takes its toll but I guess I should`t complain. Making a survey of all the modifications and years on the VIICs
would probably be a task for a historian rather than an engineer, in fact the development of the VII class has been a continious process from the very beginning. However
if we concentrate on the step from the first ordinary VIIC to the VIIC/41 you are right, the increased max. crush depth was the main thing. This was achieved by increasing the steelplate thickness particulary in the tower and controlroom area. This of course influenced the deplacement which implied a reduction of weigth. The weight reduction was obtained by doing a lot of modifications in the engineroom. By making the diesels nonreversible the heavy reversing mechanism was removed, the most visible item is the vertical reversingcylinder on top of the engine, up front. Then likewise the lubeoil purification plant. By introducing the non reversible dieselengine the surface maneuvring had to be substituted by a simpler main switch board. The switch board on all our VIICs ( ex U 995, U-926 and ex. U 1202 were all alike as all the main engines were the same. The U-995 had quite significant flare, ( Atlantic bow), the other less.  Contrary to many images the U 995, U 926 and U 1202 had a ringfloat air valve on top of the snorkel mast, not the hinged type as on the museum U 995 today. As you might see there are a lot of minor differences within the VIIC class, some time you have the feeling that several yards made, within limits, their own design, particularly in the latter part of  WW2.   U 995 never operated with snorkel in WW2, in fact she was at the yard installing the snorkel at the surrender.
Feel free to ask further questions.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 May , 2020, 16:43
FYI....
Don_

Skizzenbuck Page 106

"U-Boat Type VII C/41 Pressure Hull Construction

The Type VII C design was subjected to a weight loss program by using lighter machinery wherever possible, and lighter electrical components (i.e., the e-motor rotary switchboard control panel replaced the heavier toggle switchboard control panel). The results were a weight reduction of 11.5 tons which meant they could increase the thickness of the pressure hull in the Type VII C by 10 tons. For example; the control room hull thickness was increased from 18.5 mm to 22 mm. The test diving depth (60% of the crush diving depth) increased from 150 m to 180 m, and the destruction diving depth increased from 250 m to 300 m. This altered Type VII C construction plan was designated the Type VII C/41 because it was approved in 1941 (this was only a modification of the Type VII C and did not introduce delays in the intermediate size U-Boat building program for the contracted manufacturers). The major reason for this plan was to allow the Type VII C/41 U-Boat to avoid ASDIC/SONAR detection by diving so deep as to weaken the return ping reception to look as background noise."

In Addition:
1. Degaussing cabling longitudinally around the pressure hull and casing was removed in the late 30's to early 40's
2. The two (2) external torpedo storage tubes were no longer utilized under the deck (reduced from 14 to 12 torpedoes)
3. The 88mm cannon was removed and the need for the shell storage
4. The ASDIC/SONAR - S-Gerat equipment development was dropped (reason for the longer Control Room in VII B to VII C). This
    space was later used for RADAR equipment.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 24 May , 2020, 22:07
Don and Tore
Thank you for this fantastic information.


In regards the Switchboard  color. The general interior of the Rear Torpedo area was Ivory and all the wartime and postwar photos of Rotary (U552) and Rectangular (U995 Kaura) Switchboards looks a White color with Black controls. Or maybe it is a very light grey?


Even though U995 museum colors are now medium grey.


So would White with Black controls be correct for Wartime?


Also if White was there any reason for this color when most other equipment was a generally a shade of Grey?
Thanks.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 May , 2020, 00:54
Raymic1
The general impression of the VIIC interiors is grey and the machinery a slighter darker shade of grey. I guess the impression of Ivory on the black and white photos could derive from the reflection of the flash. The fancy green colours as on the main engines on museums U 995 might be a postwar influence from the commercial fleet as they used very often such colours. As space was a problem you did not stock a big selection of paint containers. The switchboards were light grey and the manoeuvre-wheels (switches) black. A big variation of colourstripes could be seen on the pipes, they were the colours codes use for identification for the various pipes as can be seen on the plate below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 27 May , 2020, 11:15
Does anyone know if there is a color version of the pipe identification code plate?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 May , 2020, 00:58
Katuna.
We did not use the German colourcode for the pipings, but I have a short (and incomplete) explaination of the system which migth be of some help.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 28 May , 2020, 06:12

Thank you Tore, I really appreciate it.


I remember seeing a reference to a color version of the German codes in my research but I never found it. It's out there somewhere. Would add a nice detail, as well as a little bit of color to the model.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 11 Jun , 2020, 15:50
Hello Mr Tore. I hope you are well.
For over 8 years it seems you have been sharing your photos and notes. For this we heart-fully thank you.It had been fantastic in-site into your first hand accounts of life on a Type VIIC.
I was just wondering.
As has been discussed for some reason hundreds of early pictures have disappeared  from your Posts or can no longer be opened which is a bit frustrating when we read the early posts.
At your convenience I wonder if you could just randomly reload any and all pictures you may like to share again? They don't have to be in any order.Any picture or any Uboat subject no matter.
I don't want to make it an onerous task for you, just what you feel like sharing in your own time would be fantastic to add to the history of the Uboat story.
Thank you
Mike
New Zealand
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Jun , 2020, 23:28
Raymic 1
Thanks for your post and a good idea. Quite a few of my images can be found in Dons Skizzenbuch however a few of my earliest are missing.  As they are one of a time images published for my posts only, they dissappeared when they were posted. I`ll go through my files as from my earliest posts and see if I can relocate same and publish some at irregular intervals. I regret I didn`t make a proper imagefile from the very beginning.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 13 Jun , 2020, 20:15
Does anyone know if there is a color version of the pipe identification code plate?


The color version is in Darkstars new post book. Skizzenbuch fur das Maschinenpersonal..............................................................


Click on the Imgur link and download 97 pages!!!!!!!!! Thanks Darkstar
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2020, 00:37
Mike.
Exellent find! I guess some of the modelbuilders are able to put some colours to the interiors now provided they know the systems.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2020, 02:09
Hello Mr. Tore and Mike,


Do you have access to the entire Mechanical book? It would be nice to compare it to the U-570 Mechanical book on Jerry Mason's website...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 14 Jun , 2020, 03:49
Darkstars post didnt explain very well below but f you click on the link in Darkstar130  post below it opens in the app Imgur or Chrome.
I then copy and pasted 90 plus pages one at a time. Here's his link here

https://imgur.com/a/bZAqp5v (https://imgur.com/a/bZAqp5v)


Im not sure if I can load the 90 plus pages in one go.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2020, 15:48
Hello Mr. Tore and Mike,


Thank you for the link to the mechanical book... I have cleaned up the piping color coded chart and translated. See the two (2) attached images...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 14 Jun , 2020, 17:06
Thanks Don. I tried to google translate and it didn't work very well.


Have you seen this book before? It looks like an original WW2 document. And it would seem that quite a few of its pages have been replicated over other documents over the years.
I'm not sure where Darkstar130 got it from


Lots of info in there.
Is there any other stuff on the 90 pages that is useful for your Skizzenbuch?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2020, 21:02
Hollo Mr. Tore and Mike,


Yes, this looks like a image copy of an original Mechanical book using a modern color copy machine. The copy of the U-570 Mechanical book used a mono-copy machine back in the days.  However, Capt. Jerry Mason cleaned up the U-570 mechanical drawings and that is what was used in Skizzenbuch. The Plan 3 color code page was not clear (black/white/shades of grey) so we had no idea as to the actual color of the coded pipes. Maciej Florek was going to work on the piping color coding, but fate ended that project.

I will add the color Plan 3 to the Skizzenbuch Addendum Booklet that I plan on releasing late this year...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Jun , 2020, 23:15
Don.
 I guess it is an asset to the Skizzenbuch, I wish we would have these plates in my days onboard, we had to learn it the hard way, crawling and making our own sketches in addition to the poor quality sketches available.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jun , 2020, 02:34
Hello Mr. Tore,


Didn't U-995 have the original factory mechanical and electrical books onboard? They were supposed to accompany each U-Boat when they were commissioned. Did the crews dump those books along with the enigma machine and code books before surrendering the U-Boats? Apparently, the British got all that documentation and the enigma machine when they captured U-570...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2020, 04:41
Don.
As a part of the german surrender agreement the majority of the operational german submarine fleet, about 100 submarines of all types, came to surrender in Norway. Those which were seaworty were later ordered to sail to Scotland as a part of the surrender agreement to be destroyed. This operation was called Operation Deadlight and agreed between the USA, Russian and British forces during the Jalta conference and later the Potsdam conference just at the end of the WW2. The german submarines were ordered to sail to Scotland with their original crew, flying a black flag. Those few submarines being not seaworty remained in the fjords and most of the documents disappeared. The norwegian navy eventually was able to produce som manuals in the norwegian language, in my time we had to make our own notes waiting for complete manuals.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Jun , 2020, 13:30
Hello Mr. Tore,


When you got your submarine training in the UK; was it in English or the Norwegian language? I would assume it was in English. You seem to have some knowledge of the German language since you have provided some greater depth of understanding of the German schematics. When did you pick up the German? I would think that the original German mechanical and electrical documents would have been a great help when you was the onboard EO...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2020, 14:17
Don.
My submarine training at HMS Dolphin, Gosport, Portsmouth was of course in English, but I grew up in a German occupied country were our normal english education was substituted by German. I guess, for me, some of the German language sometime is easier when it comes to submarine techniques and dieselengines in spite of having done my training in UK. I didn`t have any problem with the German documents on board the U 995.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 16 Jun , 2020, 08:28
Don - Thanks for cleaning up the color index. Just downloaded all of the pages that were posted by Darkstar. Those will be a huge help whenever I can get back on my build.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jun , 2020, 01:55
Hello Katuna,
 
Jerry Mason's website www.uboatarchive.net (http://www.uboatarchive.net) has Plan 5: General Arrangements (Two U-Boat Drawings) which were missing on the colorized prints website (Just Grey Schematics) and now you will have a complete set.

See the Attachments...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 18 Jun , 2020, 07:50
Thanks for posting those Don. I think I have the German version somewhere in all my info but not the English. It's great to see (and have) a complete book.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Jun , 2020, 18:47
Hello Mr. Tore,

I was thinking about the external canisters that held the spare torpedoes below the deck... The G7a torpedo weighed about 3,369 lbs and the G7e weighed about 3,534 lbs; a torpedo canister would displace about 4,032 lbs of water. So, I figure with the weight of the canister and the air space at the end-points of the torpedo in the canister; there was about neutral buoyancy on the loaded tubes below the deck. The G7a (T1) torpedo had a negative buoyancy of about 605 lbs and the G7e (T2 and T3) was about 597 lbs negative buoyancy.

However, my first thought would be when the torpedoes were moved inside the pressure hull, then the torpedoes weight is still on the U-Boat, only now inside the pressure hull. When the torpedo is fired, then the water from the torpedo tube is drained into a torpedo trim tank. Therefore, there is no weight change on the U-Boat. You now have the water in the torpedo trim tank countering the emptied torpedo canister below the deck weight loss.

Did they seal the canisters after removing the torpedoes?

Then the weight has not changed on the U-Boat; the torpedo was just moved inside the pressure hull. When the torpedo is fired, then water from the torpedo tube is pumped into the torpedo trim tank to maintain the balance and the U-Boat's trim line.

However, I would think if they closed the canisters, then there would be two (2) sealed canisters containing an air bubble creating a diving issue.

I believe this would be a lesser issue with the Type VII U-Boats with just two (2) external torpedo canisters, but on a Type IX U-Boat with ten (10) torpedo canisters where this could create a serious diving problem...

What do you think...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Jun , 2020, 01:36
Don.
Weight changing is a never ending story of a submarine operation, this refer not only to torpedoes, but consumables like all the items which involving the needs of 46 persons during weeks. There are many ways the weights influences the behaviour  of the vessel, like the trim moments ( alongship distances from the centers of gravity) and heights ( stability, metacentric heights.). In case of liquids, free surface effect might create problems. Hence 100% water compensated fueltanks were used. Thus a number of elements are involved. Generally you are able to control a submarine dynamically ( by speed and hydroplanes or/and by filling and draining trim tanks. In order to simplify the matter you have general rules like compensating for free surface effect by having containers either completely full or empty, using experience by compensating weight movements inside the pressurehull, like shifting crew from nightmode to battlestations (divingstations). On the U-995 you had to pump 400 ltr water from aft trimtank to fore. We did away from the torpedo containers in the casing, but should assume they would be flooded unless the weather would be bad and hence it could be a stabilityproblem surfacing ( critical just breaking the surface ). If you were entering hostile waters you would fill the Q tanks ( untertriebdzelles) to be able to dive quickly. As so many others things in life, experience rules and the COs judgment was the base of the procedure. In fact you could not make strict rules unless you involved the whole picture of the mission of the submarine, as one step would interfere the others.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jun , 2020, 02:14
Hello Mr. Tore,


If the External Torpedo tanks (Aluminum) were open, then they would flood when diving and emptied when on the surface and not creating a problem in bad weather...


Thanks again, Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Jun , 2020, 20:37
Hello Mr. Tore,

I was online with a model builder and he had what looked like rain gutters on his U-Boat (U-995) and the diesel exhaust looks to be wrong as well. I have attached a few photos... What do you think?

He also has a diesel exhaust like the last photo...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jun , 2020, 00:18
Hello Mr. Tore,

Do you have any photos that show the blister on the port side casing for the schnorchel air intake, and the exhaust piping above the deck in the starboard side. Marcus, the model builder seems to believe the all was under the deck on U-995 (Laura S-309)?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2020, 00:53
Don.
It is not easy to preserve a full open air monument like U-995 for many years unless you take corrosion precautions deviating from the original. One of the big problems are corrosions between the casing and pressurehull, hence the drain holes and the gutters on the museums U-995. I dont think the drainholes are made through the pressurehull The drains have been modified many times through the years as can be seen on my image below. Another issue is the corrosion of the pressure hull derived from galvanic corrosion while the U-995 was "stored" afloat without sacrificing elements. leaving serious caverns in the pressurehull. I really don`t see the point in copying these corrosions on a VIIC model as in such condition the VIIC would not be seaworthy. Another tendency is to exaggerate the tiny rivets in the casingplating, which sometimes gives the model a look of a tank from WW2.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2020, 01:37
Hello Mr. Tore,

Do you have any photos that show the blister on the port side casing for the schnorchel air intake, and the exhaust piping above the deck in the starboard side. Marcus, the model builder seems to believe the all was under the deck on U-995 (Laura S-309)?

Regards,
Don_
Don.

In may 1945 U 995 was installing her schnorchel at the submarine base in Trondheim, here is an image showing the final stage of the installation with the airelbow in the casing is protruding out from the casingside, this is the only part of the snorchelair inlet pipe out of the casing, the remainder is inside. Remark the float on the top of the mast has a ringfloat whereaes the present museums U-995 has a hingefloat.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2020, 01:41
Hello Mr. Tore,

Do you have any photos that show the blister on the port side casing for the schnorchel air intake, and the exhaust piping above the deck in the starboard side. Marcus, the model builder seems to believe the all was under the deck on U-995 (Laura S-309)?

Regards,
Don_
Don.

In may 1945 U 995 was installing her schnorchel at the submarine base in Trondheim, here is an image showing the final stage of the installation with the airelbow in the casing is protruding out from the casingside, thisis the only part of the snorkelair inlet pipe out side the casing, the remainder was inside. Remark the float on the top of the mast has a ringfloat whereaes the present museums U-995 has a hingefloat.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jun , 2020, 01:55
Do you remember if the exhaust piping was above the deck?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2020, 02:44
Don.
Here is the schnorchelsystem, the yellowpart of the exhaust is protruding up on the casingdeck to allow place for the exhaustblowing panel, the valves are, as you know, operated inside the pressurehull in the controlroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jun , 2020, 03:09
Don. An image of KNM Kaura ex U-995 1953 where the Schnorchel exhaustbend is clearly seen on the casingdeck.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2020, 02:20
Hello Mr. Tore,

I found a very early photo on the subcommittee.com website of U-995 and I'm now not sure about the 'Drip Line". The original photo of U-703 looks like perhaps like a "Drip Line" existed? However, the early photo of U-995 leaves me unsure... Perhaps they closed the "Drip Line" during the restoration, and then they decided to re-add the drainage later after they seen a water buildup... What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2020, 03:01
Hello Mr. Tore,

After blowing up the image, it looks like when they rebuilt U-995 that they plugged up the "Drip Lines" with small rectangular patches (welded over the drain slots)...  Then when they ran into water backup issues, they cut rectangular holes in the casing and added the gutters. What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2020, 07:59
Don.
 I wouldn`t trust the present execution of the museums U 995 as there are many modification related to the safety of the visitors. F inst. the foreship floodgates are welded shut due to people starting to climb the casingside. The image you are posting seems to be of the welded type casings, the original is riveted. I cannot remember the details 100%  but am reasonable sure there were no "gutters". The aft fairings of the saddletanks on some VIICs were equipped with floodgates as shown on my image.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 Jul , 2020, 14:47
Hello Mr. Tore,

The last photo posted has a description as "Floodgates fairing VIIC u421ausecondplantoulon.jpg"

aus = aus / Form
econd = second
plan = plan
toulon = ???

Does the title mean "Flood Gates Fairing VIIC" and "U-421 second plan" and the photo is from "Toulon, France"?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Jul , 2020, 00:13
Don. I guess the images are from a french contributor to a uboat thread and showing U-421 damaged in the drydock in Toulon, France.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jul , 2020, 11:15
We previously discussed the colour markings of the pipings as used originally. Unfortunately the frequent painting of the engineroom was carried out ad lib and eventually all the orginal paintings disappeard. As previously told we didn`t use this system, but I have an image of the engines of KNM Kaura ex. U 995 in my time showing the marking of the fuel pipes as fitted up front of the main engines. An interesting detail is the valve rocker rods, today painted blue, are on this image still not painted and hence shiny steel.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 15 Jul , 2020, 11:31
Tore - Thank you for the info. Would make sense that marking would be near either end of their run.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Jul , 2020, 00:24
Katuna, further to my post yesterday, here is another image of the colourmarking up front of the main engines, showing the fuel and and lubeoil pipes markings
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 16 Jul , 2020, 07:52
Thanks again. I've been trying to find photos from back during the war but they are very hard to come by.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 20 Jul , 2020, 05:51
Mr Tore
Are you in this Norwegian movie about Kaura S309 U995?
Click the link below

https://m.youtube.com/watch?v=05XQ_oOS4lo&feature=share&fbclid=IwAR17vc2kZETLDhw_WedvJKh4HvpLA30eEBgNCeISgp4i_q5x0o1tbWZgBps (https://m.youtube.com/watch?v=05XQ_oOS4lo&feature=share&fbclid=IwAR17vc2kZETLDhw_WedvJKh4HvpLA30eEBgNCeISgp4i_q5x0o1tbWZgBps)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Jul , 2020, 07:19
Raymic1,  I never saw the movie and I guess it was shot a few years after my time. The CO (ltn.commander) in the movie graduated a year before me at the naval academy and later became the CO of KNM Kaura when she served as a training sub when our main submarine base moved to Bergen in 1954. Very interesting to see a colour movie of KNM Kaura ex U 995 from this time. As to the scene in the engineroom you`ll see the correct colour of the paintings of the dieselengines. Some of the engineers participating were serving as my engineers in my time. PS. we never were dressed in uniform and white shirt as the officers in the movie, I guess it`s done for the moviemakers. We usually dressed in uniform when we had journalists making a submarine story onboard, like the image below, where I make some target distance calculations based on the COs report from the navigation periscope. This was just a show for the paperpeople. Thank you for sharing the movie.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 20 Jul , 2020, 17:03
What a great find on the film. In color no less. I was really happy to see the engine color I chose is almost spot on. I think it's Tamiya IJN grey, A little greenish grey. Great to see the girl in action.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Aug , 2020, 01:44
Hello Mr. Tore,

I have uploaded the latest version of the Addendum Booklet P.pdf into dropbox and you still have the permissions to download the file. If you have some time would you please review what I have created. It's 43 pages of text and mostly photos... I highly value your input...

FYI - I had another heart problem for about a week before it went away. My doctor did a PET (Nuclear) stress test and they don't see any reason for the chest pain. He changed my meds to lower my blood pressure and said if it happens again I may need to go to the hospital and have another heart catheterization done (they inject a shell fish die into your heart arteries to check for blockages and take images)...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Aug , 2020, 02:08
Hi Don.
Sorry to hear about your health issue, a youngster like you should`t experience the trouble. As for me I`m going on 92 and am currently on my summerfarm in the deep forrest with very limited access to internet. Apart from my hearing being destroyed by the engines of the old U 995 and a minor stroke, I am doing OK for my age I guess. I shall revert to your request as soon as I am back to the civilization. Keep on going, you have still to accomplish your mission.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Sep , 2020, 01:44
Don,
 I have read your last additional pages of your Skizzenbook and have following remarks as to my remarks: Page 24 plan 13 seacoolingwater somehow a misunderstanding occur in the description of the seacooling crossover pipe. The main seawater intakevalves are not air activated, the airsupply indicated on plan 13 is for the seaweed blowing, to clean the intake for seaweed, the seawater intake valve is a manual operated valve.
Page page 27, galvanic sacrificing anodes. On the image of the anodes of U 995 they are painted, the anodes should never be painted as they are sacrificing elements.
Otherwise the pages concerning my remarks seems to be OK.

Tore
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Sep , 2020, 20:08
Hello Mr. Tore,


I corrected page 24 and page 27 accordingly... I had to rebuild the Addendum Booklet folder in my Dropbox account and I would like you to check it out. The correction and to see that you have full access to the rebuilt folder... I think I got all the permissions correct??? I tested a Dropbox Business option (15 day free trial) and that changed the permissions and was almost a disaster when I went back to the standard free Dropbox account option.... I'll never do that again!


Regards,
Don_


Questions:
1. Can the inlet valve be cleared with compressed air before the inlet valve is opened?
2. Is there ever a need to clear the inlet valve when running on the surface?
3  Is there a pressure gauge on the engine control panel monitoring the inlet water pressure?
4. Where were the sea water inlet valve and compressed air blowing valve hand-wheels located?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Sep , 2020, 01:02
Don.  1. You blow to clean the intake for the seawater valve prior to it is opened as you don`t want to blow air into the coolingwatersystem.
         2. It is always a need to clear the inlet by air running on the surface, particulary at present days plasticpollution. I have experienced a full
             shut down on a passengercruiser due to a floating plastic sheet blocking the coolingwater intake.
         3. Apart from the general LP manometer there is no local manometer for the LP seaweed cleaning.
         4. The seawater inlet and grating with LP connection (called the inletchest) is located in the pressure hull  between the sea and the
             valve. The LP air pipe and valve is of a relative small dimension.
           
            Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Sep , 2020, 02:50
Don, below are some images of the seaweed blowing. N0 1 the grating in the pressurehull and the sea boardvalve with Lp blowing system as fitted in the engineroom of the museums U995.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Sep , 2020, 02:06
Hello Mr. Tore,

When the U-Boat is on the surface or schnorchelling...

The hull/sluice valves in the diesel room can provide cooling water for both diesel engines and cooling water to the e-room for the e-motor coolers, e-motor bearings, thrust bearings, e-compressor, and the junkers compressor (if present). The diesel engine's cooling water returns to the sea via the diesel exhaust muffler vents, the header tank, the exhaust muffler exit ports on the Junkers compressor (if present), and the open Starboard hull/sluice valve in the e-room.

When the U-boat is running submerged...

The Port hull/sluice valve is providing the cooling water to all said components in the e-room, and the sea water is returned to the sea via the open Starboard hull/sluice valve in the e-room. I believe this source for cooling water also feeds forward though the diesel engines and some may exit to the sea via the diesel mufflers and the header tank...

MY Question Is...

In all instances; running on the surface, schnorchelling, or submerged - The e-room Starboard hull/sluice valve is open and draining circulated cooling water to the sea.  What would be the reason for ever shutting this valve? It looks like components in the e-room require this valve to be open; including the thrust bearings???

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 08 Sep , 2020, 07:12
Don.
The intake of seawater is usually controlled by opening and shutting of boardvalves. In general all valves beween the sea and the inner part of the pressurehull is controlled by a valve having a circular valvedisc . All the valvediscs of the seavalves are opened against the seapressure, hence the seapressure keeps the valvedisc shut on the seating. As this design usually involves friction and a capacitydrop, these valves are primarily used as seaintakevalves. The seawater system inside the pressurehull is usually fitted with ordinary valves with circular valvedisks as well. The exception is the large capacity crossover supply pipe which is fitted with freeflow gatevalves and the lesser distribution branches from the crossover with ordinary valves having valvediscs.


There are several cases you need to shut the seaboard valves.  In the event of a deep dive and depth charge attack the procedure of the order: "prepare for depthcharge attack or deepdive" involves shutting of the seaboard valves.
Hence as a rule you always want to have a double security on the boardvalves.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 Sep , 2020, 14:36
Hello Mr. Tore,

Do you have a drawing of a circular valve disc assembly?

From what data I see on the e-room cooling water pump, the stats are:
Centrifugal Type
250/385 liters/minute
12 atmospheres head pressure

If the U-boat goes to a depth of 150 meters... The pressure at the e-room Port and Starboard valve heads would be 14.51 atmospheres. Therefore, the CW Pump sees no restrictive head pressure (equal pressure at both sides input and exit), so the pump can normally function and supply CW to the internal needs of the U-boat.

However, I do believe there would be a pressure differential seen between the water lines internal pressure and the U-Boat's internal atmospheric pressure. In the movie Das Boot you saw water lines bursting and rivets popping when the U-Boat plunged below 200 meters...

I definitely see a need to close the valves during a depth charge attack because of the possible differential pressures depending upon the explosion location relative to the U-boat.

Are you aware of any reported damage to the CW Pump, CW intake valve, CW exit valve, due to a depth charge attack?

Other than the attached photo...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 09 Sep , 2020, 01:27
Don the capacity of a centrifugal pump is following the QH graph as the design of the impellor, hence a given certain capacity is always followed by the head. Below is a typical drawing of a seaboard valve (As I couldn`t find a proper engineroom board valve, it`s belonging to the torpedotube system) which I guess speaks for itself, followed by a drawing which shows the internal freeflow of a gate valve. The most common reaction to a high pressure in the internal system is blowing of flangepackings and stuffingboxes.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Sep , 2020, 02:43
Hello Mr. Tore,


I have been looking closely at the e-room Port hull valve and it looks like the hull valve is bolted to a plate that is welded to the pressure hull. Also, the hull valve vent grill looks to be screwed to the welded plate as well. See the two images...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Sep , 2020, 21:32
Hello Mr. Tore,

When you dive the U-boat both diesel engines are stopped so the attached cooling water pump has stopped. However, I believe you still need to cool the diesel engine. Therefore, the cooling water pump in the e-room looks to be able to provide cooling water to both diesel engines if you opened valves e1 in the valve chest, or you could use the auxiliary cooling water pump in the diesel engine room?

1. On a dive did you normally shut both engine room hull cooling water intake valves and use the valve chest and open valves e1 to provide cooling water to the diesel engines and then shut valves e1 after the engine were cooled down?

2. I would think that you would not want to use the diesel room's auxiliary cooling water pump to cool the diesel engines during a dive because now the control for powering the U-Boat is in the e-room.

Second thought!

If the U-Boat goes very deep and is under a heavy depth charge attack... Could they close all hull valves and stop all water cooling to the e-room to protect the U-Boat from bursting pipe flanges, etc... Now they could run the e-motors at creep/crawl speed and hopefully not over heat the thrust bearings or the e-motor bearings. Do you know if this is a possibility?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2020, 00:57
Don,  normally it is up to the first engineer to decide the various components to operate as it all depends on many variable like maintenance, weather,mission etc. The various systems however are very flexible and allows many alternatives. Unfortunately some of the systemsketches are not correct as plate 13, showing the coolingwater system for the GW dieselengines. On the enclosed plate 13 I have corrected the crossover pipe allowing stb engine and the aux. coolingwaterpump to take suction  from the pipe. In general this pump will be used for the diesels instead of the E room coolingwater pump.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Sep , 2020, 01:08
Don, your last question: in emergency you do anything and I dont think at dead slow speed, major damages occur to thrustbearings, E-motor bearings etc. in case of seawater cooling is shut.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Sep , 2020, 13:21
Hello Mr. Tore,

Yes I was aware of the connection on Plate 13... I have attached the Skizzenbuch modified drawing and I noted two (2) locations with a RED circle on the print.

It's good to know that the diesel room auxiliary CW Pump was used to continue cooling the Diesel engines. Do you remember how long that process would last? I would not believe it took too long...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Sep , 2020, 18:48
Hello Mr. Tore,

I have attached below a photo of the various diesel exhaust arrestor on Kaura (ex U-995) and others:

1. If the exhaust exits the spark arrestor above the water line is there a staring black smoke?
2. If the exhaust exits the spark arrestor below the water line is there a starting white smoke?
3. Was there ever a time when actual sparks were seen exiting the above the water line spark arrestor?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Oct , 2020, 00:36
Don. The exhaust is usually an indicator for the condition of the engines like fuel nozzles and coolingwater leakages. Normally you would not notice any black or white exhaust. A bad fuelnozzle or overload would create a black exhaust and white smoke a coolingwater leakage like corrosion holes in the exhaustvalvecage. Nevertheless the exhaust would leave some deposits of black carbon at the exhaust outlets  and you migth see some of the VIIC casings  have been painted black just above the outlet to disguise the deposits. You very seldom see any sparks at the exhaust outlets.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Oct , 2020, 23:14
Hello Mr. Tore,


Can You look at the attached image and answer the question between Simon and I???


Regards,
Don_


PS... Sometimes it may be a good idea to read my own book...



Exhaust Port and the Spark Arrestor


The VII Cs had a number of different exhaust outlets and possibly spark arrestors. The colleague of photos to the left shows 5 versions. The spark arrestors for U-Boats may be of two executions; wet or dry. The dry spark arrestor has an intricate system of baffle plates to arrest the sparks inside a casing. In the wet execution, the engine cooling water is sprayed into the arrestor or the gases are emitted into the water cooling well. In both instances they are placed above the water surface (sea). Another version is when the exhaust is emitted below the water surface (sea) without any special casing for a spark arrestor. The latter execution was the original U-995 design [Top right photo (RED circle) KNM Kaura/U-995 in dry dock in 1953]. This was changed on todays museum U995 as shown on the top left photo; the RED circled area indicates the Bold ejection port just aft of the rebuilt exhaust outlet location.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 02 Oct , 2020, 21:32
Hi Tore & Don

A few questions about the Spark Arrestor and if it utilized cooling water.

* In the Design and Specification Books, Volume M on plate 13B, it shows no cooling water going pass the end of the diesel exhaust silencer.
* If it did spray cooling water into the Spark Arrestor, how was the amount of cooling water control?
* If cooling water was sprayed, this would lead to negative pressure in the cooling water system, does this mean they had to constantly add sea water to the system to replace the lose cooling water?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Oct , 2020, 02:27
Don and Simon.
As Don says there are a number of executions to the exhaust outlets in the casing,  the execution I guess, might depend on the on the mission for the relevant boat. As on Dons image, the sparkarrestor is clearly visible adjacent to the silencer. Water spraying in the sparkarrestor is mainly a design for motorlaunches and I cannot remember it is used for the VIICs, a better solution would possibly be to end the exhaust pipe below the watersurface. The exhaust system is cooled by the main coolingwater system which leaves the pressurehull via the mantel of the main hullexhaustvalve  with intricate passover the flanges up to and including the silencer. From the silencer the pipesystem end up in the fuelcompensating headertank in the towercasing having an overflow under the casingdeck to the sea, thus not visible. There are quite a few drain valves in the system allowing for draining the coolingwater mantels ( for artic operations). Below is an image showing the original exhaustoutlet in the casing as originally fitted on U 995 during the hand over October 2.  1971.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Oct , 2020, 11:16
Hello Mr. Tore and Simon,

I do not believe we would ever see a negative water pressure in the cooling water system... Once the water compensation system is stabilized there is no further drain on the cooling water system because the diesel engines are drawing fuel from the day tank which is not water compensated. Therefore, the constant cooling water drainage is at the mufflers and at the header tank under the winter garden. Each engine mounted water piston pump can supply 48 cubic meters of CW per hour (the Electric Auxiliary CW centrifugal pump has the same capability). This definitely looks to be a pressurized cooling water system by design.

It looks like both U-995 and U-926 originally had the exhaust exit below the water line according to the shipyard and surface images. U-995 was converted to the exhaust exit above the water line during the museum refurbishment. This is one more item that they should have left as original!

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2020, 00:20
Hello Mr. Tore and Simon,

Sometimes I over think things, but I will just ask the question... This excellent Simon drawing shows the red pipe directing Cooling Water from the mufflers to the header tank. If only one (1) Diesel engine is running and CW is flowing to the header tank, it would also be back flowing CW into the opposite muffler. I believe if there was a one-direction check valve in each muffler line (or in the muffler itself), then this would eliminate the waste of Cooling Water.

If both diesel engines were running, then both supply CW to the header tank.

Question - Do you know if there was such a one-direction check valve in the muffler line?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 04 Oct , 2020, 00:51
Don, a good questions. I only guessing, I imagine some of the CW would escape but most would make it to the Header Tank.

I also have a question about the Cooling Water from the mufflers to the header tank.

I estimated the size of the two pipe coming out the mufflers at 75 mm. Does this mean that the pipe from the joint of the two pipes to the header tank is 106 mm (e.g. almost double the flow) or is it the same size pipe all the water to the Header Tank?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Oct , 2020, 02:14
Simon
As it is only a headertank I guess the pipe is 75 mm.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2020, 02:52
Hi Simon,

After looking at the Cooling Water line size (75 mm) and the obviously smaller size of drain lines placed at the top side of the muffler, I would think that the Cooling Water pressure would easily force CW up to the header tank (those drain lines at the top of the muffler also serve to get any air out of the muffler CW chamber). CW flowing from the muffler will keep the muffler temperature at an acceptable level depending on the outlet pipes diameter.

Just my opinion - I do not believe the pipe diameter is increased going to the header tank. The header tank serves as a reservoir for the fuel tanks water compensating system, and this system is only drawing water when fuel is being transferred to the day tank. So, you have CW overflow drainage at the header tank and CW drainage at the two (2) muffler drain pipes.

However, all is dependent on Mr. Tore comments...

Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2020, 03:42
Hello Mr. Tore and Simon,

Has anybody thought about a repository for all of the information in Tores Mailbox, personal documentation, with regards to the Type VII C U-Boat. The documentation that I have on my computer that went into the creation of Skizzenbuch and the coming Addendum Booklet (doc, pdf, photos, and drawings), and the many drawings that Simon has spent thousands of hours creating?

Mr. Tore started this adventure on January 12, 2012, and is in his 90s, and I will turn 80 next year, and of course I believe Simon is about half our age... However, Simon can create engineering type 3D drawing from U-Boat remains sitting on the ocean floor.

Do we have options for preserving our work for future U-Boat enthusiasts?

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Oct , 2020, 04:06
Don and Simon.
The coolingwater has generally a common seawaterinlet via the inlet crossoverpipe and a common outlet via the exhaustcooling headertank. Both the inlet and the outlet can be selected if need be, however normally you use a common inlet and a common outlet for both engines.  As the coolingwater discharge for both engines are commonly connected by the headertank, both port and stb.systems have the same discharge head and need no checkvalve as they are hydraulically ballanced by the headertank. Ref. plate 10 below.
Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 Oct , 2020, 21:01
Hello Mr. Tore,

On sheet 10 (Fuel Oil Compensating System) that you previously posted, valve (a) shut stops high pressure in a dive from over pressurizing the internal fuel oil tanks. However on sheet 13 (Cooling Water System) I did not note a shut-off valve at the muffler side with all the different cooling water jackets and bends leading to the diesel engine; is there one? There is a shut-off hull valve on the port and starboard side taking sea water to the diesel engine water pumps.

A second question - on sheet 13, would they normally leave valve (h) open to allow both the port and starboard engines to draw cooling sea water from either hull valve. That way they could isolate either filter and replace/clean it while running both diesel engines...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 06 Oct , 2020, 15:03
I have worked out the alignment of the main pipe from the Muffler to the Header Tank base of a single war-time photo. The alignment is different than I previously believed.

Base on the inlet openings on the Saddle Tanks and Pressure Hull, I have a high level of certainty that these pipes entering the Saddle Tanks and Pressure Hull are around 55 mm. These are the pipes from the Header Tank to the MB & RFO Tank 2 & 4 and Engine Room.

Its also about the only way this pipe can make it to MB & RFO Tank 2, there very little space for pipes in this area (in fact I don't think I could get a 75 mm to MB & RFO Tank 2 without restructuring the deck height).

If we say these are smaller pipes entering the Saddle Tanks and Pressure Hull, do you think the main pipe from the Header Tank to the 4 way pipe connector is the same size (55 mm) or should be it be bigger at 75 mm?   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Oct , 2020, 03:15
Hi Simon,

Interesting... Plate 10 does indicate that the pipe from the header tank going to MB & RFO Tank 2/4 and to the pressure hull are smaller. The pipe coming from the header tank to the mufflers and the over-flow drainage pipe are larger.

The capacity from both running diesel engines water pumps would be about 96 cubic meters of cooling water per hour; Therefore I believe the larger diameter pipe from the mufflers may be required, as well as the larger diameter overflow pipe from the header tank.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Oct , 2020, 08:02
Don and Simon.
Sorry I have been away for a few days. I guess Simons observation that the common CW pipe from the two silencer to the headertank is larger than the direct makeup lines between the headertank and silencer is correct, the overflow of the headertank must be able to handle the full coolingwater capacity of both engines. I guess the supply pipe from the headertank through the pressurehull would be 55mm diam all the way including the shutoff-  and reliefvalves inside the pressurehull.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 09 Oct , 2020, 01:28
Hello Mr. Tore,

I took the drawing of the bow torpedo tube and door and added the two(2) drawings below to illustrate the outer door opening with the drawings below. What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Oct , 2020, 14:41
Hello Mr. Tore and Simon,

As you know, I have been working on an Addendum Booklet to supplement Skizzenbuch with our later discussions and any needed updates or corrections. I believe that we all have done a pretty good job with the initial Skizzenbuch, and the Addendum Booklet is currently scheduled for a release date of December 1, 2020. I have uploaded my latest version of the Addendum Booklet in dropbox, and I believe I only need to replace the image on page 47 with an update. If there is anything that I have missed, or needs to be included, then please advise...

Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 12 Oct , 2020, 13:23
Hi Simon,

Interesting... Plate 10 does indicate that the pipe from the header tank going to MB & RFO Tank 2/4 and to the pressure hull are smaller. The pipe coming from the header tank to the mufflers and the over-flow drainage pipe are larger.

The capacity from both running diesel engines water pumps would be about 96 cubic meters of cooling water per hour; Therefore I believe the larger diameter pipe from the mufflers may be required, as well as the larger diameter overflow pipe from the header tank.

Regards,
Don_

The largest pipe I could get to fixed was 60 mm, so I will go for that.


Don and Simon.
Sorry I have been away for a few days. I guess Simons observation that the common CW pipe from the two silencer to the headertank is larger than the direct makeup lines between the headertank and silencer is correct, the overflow of the headertank must be able to handle the full coolingwater capacity of both engines. I guess the supply pipe from the headertank through the pressurehull would be 55mm diam all the way including the shutoff-  and reliefvalves inside the pressurehull.
Tore

I used a online flow rate calculator and it said to match the same flow of both engine, the minimum size the pipe would need to be was 100 mm.   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Oct , 2020, 15:48
Hello Mr. Tore and Simon,

I attached the photo of the mufflers and the pipe to the header tank, and the bend pipes from the diesel engines.  What I have noticed is the bend pipes are much smaller in diameter than the pipes to the header tank. Therefore, the flow capacity going to the mufflers is restricted to some degree, but the larger pipe size from the mufflers seems to reduce the CW pressure going to the header tank.

Remember, the 48 cubic meters of water per hour provided by each diesel engine water pump also flows towards the aft of the U-Boat to cool the thrust bearings plus other items in the aft torpedo room and exits at the aft drain port to the sea (Attached Plate 13 drawing). So, the CW pipe to the header tank doesn't need to be such a large diameter (i.e., 100 mm).


Simon, is there anything in the muffler photo that would allow you to determine the size of the bend pipes and the muffler pipes?

My Thoughts,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: NZSnowman on 13 Oct , 2020, 18:08
Fuel Oil Compensating System

(https://live.staticflickr.com/65535/50474215902_ac0821eacd_o.png)
Fig. 1. Overview of Fuel Oil Compensating System (red).

(https://live.staticflickr.com/65535/50473404743_99b0a7444a_o.png)
(https://live.staticflickr.com/65535/50474260672_d7f25ed27d_o.png)
(https://live.staticflickr.com/65535/50474260822_9d77a794d8_o.png)
Fig. 2, 3 & 4. Aft section of Fuel Oil Compensating System (red). Have not found any evidence of the true pipe alignment or the type or location of the drain valve 'e'. I have photograph evidence that indicates that the line back to the header tank runs along the starboard side of the boat. There a deck hatch just forward of the exhaust valve (orange) so I located the drain valve 'e' below this hatch.

(https://live.staticflickr.com/65535/50473493418_331d987e24_o.png)
(https://live.staticflickr.com/65535/50474347722_b737fb215c_o.png)
(https://live.staticflickr.com/65535/50473493523_396b910698_o.png)
Fig. 5, 6 & 7. Mid section of Fuel Oil Compensating System (red). Have not found any evidence that the pipe runs down the inside of the air inlet pipe but highly likely as there no room for piping on the starboard side. Have not found any evidence where the '4 way' pipe junction is located. We know where the inlets are on the saddle tanks so base on that and the deck hatches, I have located again under the hatches valve 'b'. You can also see I have located the exhaust blowing valve 'h' under the same hatch (orange).

(https://live.staticflickr.com/65535/50474304441_59afe60d53_o.png)
(https://live.staticflickr.com/65535/50474304386_83bebba127_o.png)
Fig. 8 & 9. Header Tank of Fuel Oil Compensating System (red). Have not found any evidence of the layout of the header tanks but this layout seems most likely (I still need to fixs the Header Tank outlets). I found evidence the pipe running forward on the starboard side of the CT.

I need to do more research on how the piping goes around the CT, the alignment of the overflow pipe, and the alignment of the piping inside the saddle tanks to the expansion tanks.

A good start to the Fuel Oil Compensating System, I been working on this system for about four years now, so it great to see it nearing completion.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Oct , 2020, 00:36
Simon. Congratulation!  Amazing piece of research and drawings, whishing we had similar drawings for instructions in my time.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Oct , 2020, 00:50
Hello Mr. Tore,

I agree, Simon is a very talented young man who has researched and produced outstanding U-Boat drawings which will prove to be very accurate. I believe our teamwork with past and present members of "Tores Mailbox" has contributed to the knowledge base of the Type VII C U-Boat and we all can take pride in our work.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Oct , 2020, 14:04
Hello Mr. Tore and Simon,

I believe that I have just completed the Addendum Booklet to Skizzenbuch and I don't foresee any additional updates. Would you please review the booklet and especially check-out page 47 which is the latest entry and let me know what you all think?

I believe we have completed the Skizzenbuch: U-Boat Type VII C Project...

Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 12 Nov , 2020, 14:12
hi Don. I just PMed you.
Thanks
Mike



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Nov , 2020, 17:29
Hello Mr. Tore and Raymic1 (Mike),


The content (Text and images insert) on page 199 were a contribution from Mr. Tore... Mr. Tore, if you still have the photos of the hydroplane motor and clutch mechanism or any additional photos, then could you please post them here for Mike?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 15 Nov , 2020, 12:01
Mr Tore.
Would you have the original high resolution pictures of the Aft Hydroplane motor and clutch area that you could share?.
Mine from the Skizzenbuch are not very clear.
Thanks
Raymic Mike
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Nov , 2020, 23:02
Hello Mike,


I found the one image that I used to create the composition on page 199. I do not know if it is of any help...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Nov , 2020, 23:53
Hi Mike!
 I have looked into my files (which is not very impressive) and did`t find any better image than Dons. Sorry I wasn`t very organized at the time of  publishing the image and in the meantime quite a few images disappeared.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 16 Nov , 2020, 00:00
Thank you Don and Tore.
I have searched everywere on the net for these particular images with no luck. I wonder where they originated?
But Don your originals are more than good enough. I can see the extra detail that is lacking in the PDF .
Thanks again
Mike
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Nov , 2020, 00:13
Hello Mr. Tore,


I guess I was asleep in class, or my old age has set in... What is the function of these hand-wheels???


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Nov , 2020, 09:06
Don.
Your image shows the shut off valve in the air pipe to the starting airvalve in the cylindercover. As you remember by opening the main startingair supply you are at the same time opening for the airsupply to the top of the starting valve where a piston the is actuating the push rod engaging the roller to the camshaft, which then opens and shut the startingvalve at proper timed intervals. I guess in the official diagram they have forgotten this valve. By shutting the air valve, the pushrod roller is not engaging the roller to the camshaft and the startingair valve for the relevant cylinder is not operating.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Nov , 2020, 15:22
Hello Mr. Tore,

Looking at the starting valve is the lower half in the starting valve an injector? It looks like the roller rides on a high spot on the cam, then the nozzle in the lower section of the starting valve opens.

The starting air cam roller that activates the push rod and rocker arm to inject starting air to all six cylinders. However, only one of the starting air valves at the cylinder head is open and drives the piston downward.

Am I close to correct:
1. Is there a 3rd valve in each cylinder head that is only activated (opened) while running on starting air?
2. When the 3rd valve for each cylinder is opened, starting air enters the cylinder chamber and drives the piston downward?
3. When the starting valve is not under starting air pressure, then all of the 3rd valves in the cylinder head are shut?
4. I assume the reason for the 3rd valve is to stop combustion gases from feeding back into the starting air system?

As you can see, I get lost sometime and have to find my way back... Do you have a engine drawing that shows the starting valve and the air lines to/from it, and a cross section of the starting air valve in the cylinder head?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2020, 03:18
Don, you are entering into a complicated system consisting of hydraulic, pneumatic and mechanical elements with a lot of interlocks if you want to include the direct reversible system of the GW dieselengine, as you know the complicated direct reversible system was omitted as from 1943 on the GW engines. On the U 995 engines you `ll find only rudiments from of the direct reversible system. As to the starting system it works as follows, each cyindercover has a separate starting valve timed and operating from a modified camshaft by rollers,cams and pusrods. The starting valve looks like on my image below and consist of a common housing with a long valvespindle having a valve in the lower end, the chamber in the valvehousing has a direct connection to the startig air supply, the valvespindle goes through the startingairspindle chamber via the lower airtight springcarrier/ guide and a shutting spring up to the upper spring carrier. The upper valvespindle ends in an adjustable connection engaged to a springloaded lever connected to a valve rod ending in a roller arm. The startingvalve rocker system is kept free from the camshaft by a spring on the valve lever keeping the rollers away from the camshaft In the starting procedure starting air is admitted to the top piston of the startingvalve spindle, forcing the startingvalverod down agains the springload and engaging the roller to the camshaft, which operate the starting valve mecanically. When the starting sequence is over, air pressure on the valve spindle toppiston is vented and the starting valve spring lever is pulling the system free from the camshaft.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2020, 04:34
Hello Mr. Tore,

Let me start to learn how the Starting Air System works on a step-by-step basis with a few basic questions each time.

Starting Air Distribution

1. Is there only one (1) Starting Air Valve on the Diesel Engine?   yes/no
2. When starting air is supplied to the Starting air valve at the top, then the roller will engage the cam?  yes/no
3. When starting air is supplied to the center section of the starting air valve, then starting air is supplied to all six (6) of the Cylinder head's starting air valve chambers?  yes/no

Let's get an answer to these three (3) basic questions...

Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2020, 05:15
Don.
1. No.There is one starting air valve pr. cylinder e.g. 6 startingvalves for a 6 cylinder engine.
2. Yes
3. Yes, but starting air in the chamber to the cylinder is only admittet through the relevant starting valve being opened by the pushrod of the relevant cylinder.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2020, 12:38
Hello Mr. Tore,

4. Where is the starting air valve located relative to each cylinder head?
5. Do you have a photo of a starting air valve?
6. Is the shifting cam shaft one long continuous shaft to all cylinders?  yes/no
7. There is only one shifting cam shaft with cams for both the push rods driving the intake and exhaust valves, and cams which drive the starting air valves?  yes/no
8. Does the shifting cam shaft rotate one full revolution per two (2) revolutions of the crank shaft?  yes/no

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 24 Nov , 2020, 13:38
Don.
4.Down below is Simons image of the cylindercover where the starting valve for each cylinder is shown fitted.
5. I don`t have a photo of a separate starting airvalve.
6. The camshaft is the same as the original camshaft along the engine.
7. Hence the originalcamshaft is driven from the camshaftdrive as normal.


Tore
 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2020, 14:27
Hello Mr. Tore,


9. How does the starting air get to the middle connection on the inserted starting air valve which is placed into the engine valve head? I see the top connection pass air through the shut-off valve to the upper section of the starting air valve, and then it forces the roller to engage the cams...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Nov , 2020, 23:35
Hello Mr. Tore,


Thanks for the last few posts...  I think that I'm beginning to understand how the starting air system works.


I added some ID tags on one of your drawings and I hope that I got it right...


10. when is the Shut-off valve used on a cylinder? Why?
11. Was that spring an added modification by crewmen (Starting valve spring.jpg attached)?

Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Nov , 2020, 01:11
Don.
Below is one of Simons drawings which shows the starting air supply pipe to the starting airvalves of each cylinder. As you see the startingair valve casing is protruding up over the cylinder covertop allowing space for an airchamber flangeconnection to the starting air supplypipe going along the main engine at the level of the starting airvalve connection. The shut off valve to the engaging piston on the top of the valve is clearly seen, I guess the shut off valve could be used if for some reason you would disconnect the rockerarm from the camshaft. The spring for retaining the rocker arm from the camshaft is a typical device of the prewar technology and is an intergral part of the system, not somebodys funny idea. If f.i. a starting valve for some reason stays open or start leaking, the combustion pressure in the relevant cylinder forces hot exhaust gases into the starting air system overheating the pipes. It happened to me ones upon a time and the painting on the startingpipes became so hot that the painting started to boil.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Nov , 2020, 20:42
Hello Mr. Tore,

During WWII, was there ever maintenance at sea on a diesel engine where a head valve, piston, or any other major component was replaced where the lifting bars were utilized? I don't believe in your situation at sea where you could go back to port that these types of repairs were ever done...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2020, 00:39
Don
I have no records of any maintenance at sea by the germans during WWII, but based on my experience from the VIICs I guess it could be quite a few. You are right in your assumtion that we carried out major repairs at shipyards along our coast, being about 30.000 km long. Repairs like changing big end bearings and exhaust valves, even a seized supercharger was done by our own crew, otherwise planned maintenance was carried out a our yards.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Nov , 2020, 03:19
Hello Mr. Tore,

Would you carry spares like: fuel pumps, oil pumps, air starting valves, etc? Intake and exhaust valves would require pulling a head casting and all those connections; would your crew do that at sea? It seems like replacing an end bearing would be more difficult at the clutch (aft) end than at the forward end of the engine. Were you limited to the spare parts because of shortages of parts from German shipyards that were destroyed during the war?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 28 Nov , 2020, 11:11
Don.
Spares like oilpumps, and starting air valves were not stored onboard. Consumeables like fuel nozzles, fuelpump plungers were stored. Exhaust and inletvalves with cages was a routine job. Big end bearings were not a problem. The germans left behind a considerable amount of spares in the large submarine pens which were constructed for a larger submarine fleet than ours.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 28 Nov , 2020, 21:19
Hello Mr. Tore,

Then if your spares included Intake and Exhaust valves, then your crew used the lifting bar to pull the head casting to replace the valves. That seems like a very time consuming Job to me, along with replacing the crankshaft bearings - Wow! It's a darn fortunate thing that you were not being hassled by Allied aircraft and British Destroyers when attempting to repair an ailing diesel engine...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Nov , 2020, 00:54
Hello Mr. Tore,


Simon and I were having a discussion about the lines going to the Starting Valves, and I think that the Germans installed a pressure relief valve at the end of the air pressure lines feeding the starting valves lower chamber. If there was a water stroke, then the air pressure would build up and pop the relief valve and possibly avoid any engine damage? See the image and what do you think?

Question - How do you blow out the cylinders with HP air? Open the cylinder drain cocks and what else is done?

Bear with me for a moment... What is a water stroke. Near TDC the exhaust and the intake valves overlap by about 20 to 60 degrees. So a piston could be near the top of the cylinder with both valves open. If there was a water intrusion; then water could go from the exhaust valve chamber, to the cylinder chamber, and then to the intake valve chamber. Now, the first time the piston does an intake stroke, the water from the intake valve chamber is drawn into the cylinder, and then on the compression stroke we get a "Water Stroke" because the piston cannot cycle to the top of the cylinder??? Comments?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Nov , 2020, 02:17
Don, I have rewritten your two starting air pages of the Skizzenbuch but have trouble in mailing the correct images, at my age (92) I am not very familiar with the E-mail and shall get some help from my grandson next week. My pages explains the starting air system bit further incooperating the maneuvrehandles with manifold. The relief valve on the end of the starting air common rail is adjusted to 75kg/cm2 and with a lifting hight of 12mm too small as a waterstroke cylinderprotection, remember water is acting like a solid rather than a gas. The starting system allows for manual control of the starting air independently of the fuelinjection, hence you can run the engines on air only. As a safetyprecaution you always run the engines by air and open indicatiorcocks, one for each cylinder, open. We called that "blowing through the engine". By massive intrusion of water we sometime cranked the engine by hand with open indicatorcocks.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Nov , 2020, 03:13
Hello Mr. Tore,

Thanks for the update...  The U-Boats HP air is capable of 205 Kg/cm square and that's 2,915.79 psi which is huge. Then the pressure relief valve for the starting valve line to the lower chamber was limited to 75 Kg/cm square, or 1,066.75 psi, and it looks like this is the limit of air pressure that may be used to start the diesel engine without popping the relief valve.

Question #1.  Exactly, what was the function of the relief valve? Could you over pressurize the diesel engine with the starting air valve since the bottle source could be 205 Kg/cm square?

A water stroke would happen during the very first 360 degree turning of the crank shaft when you attempt to start the diesel engine with air. The crank shaft speed would be slow and only the air pressure is driving the piston. When you turn the handle on the starting air valve, the air pressure would go from low-to-high. I would think that a water stroke would just stop the crank shaft from turning and not damage the piston, piston connecting rod, the crank shaft journals, or the crank shaft???

However, if I do the math - The piston diameter is 400 mm = 15.745 inches, so the piston surface area is 194.6 sq inches. Now, if we apply 1,066 Psi (75 Kg/cm square) of air pressure, then the total pressure could be 207,449.40 pounds on the piston top... Yep! I guess things could break...

Question #2.  Mr. Tore, what usually broke?

Question #3.  Was there an air pressure gauge that displayed the Starting Air pressure that was applied to start the diesel engine?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 29 Nov , 2020, 07:15
Don.
It seems I have overlooked a basic element in your understanding of a four stroke engine, the compression and ingnition.
 If you have water intrusion in the engine it usually enters via the exhaust system. The combustion air enters via the engine room as the induction air ducts ends near the outboard bilge. On the exhaust side the usual reason for the water intrusion is the carbonization of the valve seating of the main hull exhaust valve. Allthough you having the pneumatic grindingdevice for the valveseating, leakages occur for several reasons. Time is a major factor, grinding of the main hullexhaustvalve starts as soon as the engines are stopped and boat is ready for diving e.g. totally shut pressure hull and on the COs order. An important element in the grinding is seawater backpressure on the flapvalve disc, hence you want grinding the valvedisc as soon as you leave the surface. Two elements works against this, the pneumatic grinding is noisy and consumes a lot of HP air building up the pressure inside the sub. A third element reduce the grinding time, as you reach about 5-6 meter the flapvalve backpressure becomes so great that the pneumatic motor can`t overcome the grinding friction and stop. All these elements counts in the risk of water intrusion. An ideal dive from the exhaustvalve grinding point of view is 4- 5 meter for some 3-5 minutes, but that is wishful thinking.
 If you are unlucky and have to keep the periscope depth after a crashdive you might have a massive waterintrusion, the 2nd hull exhaustvalve has a special high drain capacity to the bilge, but in the worst case not large enough and might overflow and flood the exhaust manifold along the engine. In spite of drain to the bilge the manifold can be flooded  and water might enter the cylinders. If you start an engine with water in the cylinder equal to the compression volume (dead volume)you might have a waterstroke in the cylinders reaching the compression (ingniton) stroke as the water is trapped solid in the compressionvolume. The collateral damage by the rotating masses can be substatial.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Nov , 2020, 17:30
Hello Mr. Tore,

After reviewing all the material we post last week... This is my understanding about a water stroke:

1. A diesel engine is shutdown with one cylinder/piston in the exhaust stroke position
2. The piston is low in the cylinder and the exhaust valve is open (creating an entrance and space for sea water)
3. Another cylinder/piston is in the power stroke position
4. The exhaust system failed and there is a massive sea water intrusion
5. The cylinder/piston in the exhaust stroke fills up with sea water (also the valve head area and the manifold)
6. Starting air is enabled for all cylinders
7. Starting air is applied to the cylinder/piston in the power stroke position
8. The crank shaft attempts to rotate
9. The piston with the sea water filled cylinder attempts to move upward
10. The sea water pushing through the open exhaust valve port creates a huge back pressure (pressure shock)
11. The exhaust cylinder piston barely moves as the pressure increases on the power cylinder piston
12. The starting air valve continues to supply HP air to the power stroke cylinder (increase pressure)
13. The exhaust cylinder piston has a "dead head" (no motion)
14. This is a water stroke

When a diesel engine is normally running; in the exhaust stroke, while the piston is moving upward the burned fuel gasses are compressed as they are forced around the exhaust valve and out the exhaust head port. However, with a water filled cylinder there is nothing to compress which stops all crank shaft rotation, and applies excessive back pressure on the driving piston in another cylinder chamber.

Did the pressure relief valve pop/release when you had a water stroke? Is it just a signaling device, or did the pressure relief have some effect on the starting air system (Shut-off the starting air system)?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2020, 02:08
Don.
Waterstroke. Starting air pressure at 30kg/cm2 is normal for a medium speed engine. The GW engine starting system allows the engine to run on the air (without fuel injection) for a manually controlled time. By allowing the engine to run at full air pressure it picks up speed very quickly.  At a massive waterintrusion filling the engine exhaust manifold, water might enter some of the cylinders and cylindercover inlet and exhaustvalve ducts draining down on the piston top. The compression clearance in the cylinder is 6,6 mm leaving only a very small compression volume in the cylinders during the compression stroke, ( piston at TDC. and all valves shut). Hence at the wrong quick start, the rotating massforces might create an impact between the cylindercover under side and the water on the top of the piston with collateral damages. Some of the engineers were experts in manually controlling the airstart, managing to reduce the starting air and blowing the water out of the open indicatorcocks before the engine picked up speed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Dec , 2020, 03:42
Hello Mr. Tore.

"Hence at a wrong quick start, the rotating mass force might create an impact between the cylinder cover under side and the water on top of the piston with collateral damages."

1. I agree, the cylinder/piston was driving upward in an exhaust stroke with an open exhaust valve, but the water is not pushed out through the exhaust valve port in the head cover because of back pressure; and water is not compressible.

2. I agree, If the start-up is very slow with the indicator cocks open, then this process may clear the flooded cylinders.

3. Was the water stroke primary damage done to the piston or the cylinder cover?

4. What was the function of the Pressure Relief Valve?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Dec , 2020, 06:08
Don.
At the beginning of the compression stroke a piston moves from BDC to TDC and the exhaust and inlet valves are shut. Prior to this stroke is the inletstroke and the air inletvalve is open creating a suction when the piston moves to the BDC. At this point some of the trapped flooded seawater left in the cylindercover airducts drains into the cylinder and piston top. This seawater reduces or even might eliminate the smallcompression volume (compression clearance 6,6 mm) which might create an impact force on the cylindercover bottom plate by the rotating masses at the air start and you have a waterstroke.
We never experienced a waterstroke so I personally have not seen the damage, but assume the cylindercover bottom and overstressing the cylindercover bolts could a damage.
As on every high pressure vessel a relief valve is installed in the cylindercover. The function is to protect same for excessive high pressure stresses which might occur, like misfire of a cylinder.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Dec , 2020, 13:27
Hello Mr. Tore,

"At the beginning of the compression stroke a piston moves from BDC to TDC and the exhaust and the inlet valves are shut."

I understand this part...

"Prior to this stroke is the inlet stroke and the air inlet valve is open creating suction when the piston moves to the BDC."

I understand this part...

"At this point some of the trapped flooded sea water left in the cylinder cover air ducts drains into the cylinder and the piston top."

I don't understand this part???

The sea water intrusion was on the exhaust side of the diesel engine. Therefore, the exhaust inlets in the top cover are flooded, and water may enter through the open exhaust valve and drain into that cylinder on top of the piston.

How does the sea water intrusion get from the EXHAUST INLET side of the top cover to the AIR INLET side of the top cover to flood the cylinder chamber during the intake stroke? I thought the intake and the exhaust chambers in the top cover are physically separated?

As I pointed out previously... If a cylinder piston was neat TDC in an exhaust stroke, then both the inlet valve and the exhaust valve are open (valve overlap with 20 - 60 degrees). Therefore, with this rare occasion you could have sea water entering the exhaust top cover chamber and then flooding into the cylinder chamber and over flowing into the air inlet chamber in the top cover.  With this scenario, I could see a compression stroke where a solid piston stop would happen "DEAD HEAD"...

I don't know of any other way to get sea water into the air intake head top cover...

Am I missing something else?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Dec , 2020, 02:53
Don.
 I don`t think you are missing anything and agree with your conclusion of filling the inlet ducts by the exhaust flooding water and am sorry to have mentioned the waterdrain from the valve ducts as it is confusing. I once experienced filling water in the cylinder from the exhaust valve having a waterleakage into the cylinder from one of the exhaustvalves water cooled cages having a corrosion hole while the engine was running, but did not experienced any waterstroke as the water evaporated prior to reach the pistontop. We better stop mentioning the exceptions and stick to the basics.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 02 Dec , 2020, 15:38
Hello Mr. Tore,

Then if your spares included Intake and Exhaust valves, then your crew used the lifting bar to pull the head casting to replace the valves. That seems like a very time consuming Job to me, along with replacing the crankshaft bearings - Wow! It's a darn fortunate thing that you were not being hassled by Allied aircraft and British Destroyers when attempting to repair an ailing diesel engine...

Regards,
Don_


I remember reading that the Germans packed as many crates of spares as they could on board, both below decks and around the Engine Room. I know when U-534 was cut into sections, they found parts crates including a piston and I think a con rod and a liner. they were stored around the engines. I'm sure a lot of smaller parts are stored under deck on the fuel/oil tanks.


Are the racks between the frames, behind the engines original to that time period or were they added after the boat was turned over?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Dec , 2020, 01:52
I guess I have mentioned it before,  but we found a barrel where a piston was stored in conservation oil onboard KNM Kaura ex. U 995 at that time I was very young and engaged or newly married. In those days we used engagement rings of gold. To get a ring we had to trade in gold at the goldsmith and my wife at that time working for WHO in new Dehli bought som gold to trade trade in for the rings. Opening the barrel I wanted to check the piston submerged in the slippery oil and all of a sudden my ring slipped off and disappered in the barrel. It was of course a disaster and I must confess I used my engineroom crew to retrieve the ring with some work and my marriage was saved. We are still married, this year for 65 years.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Dec , 2020, 03:29
Hello Katuna,


As far as I know the metal storage bins in the diesel engine room are original items.  It would make no sense for them to create storage bins during the retrofit and not use them?  Here is an attached photo from the Skizzenbuch Addendum Booklet...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 03 Dec , 2020, 06:44
Yes Tore, you must have mentioned it before, I remember the story about the ring.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 06 Dec , 2020, 13:47
I had forgotten your ring episode! Thanks for sharing again.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Dec , 2020, 01:56
Hello Mr. Tore and All...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 20 Dec , 2020, 01:37
j
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Katuna on 22 Dec , 2020, 08:25
A very Merry Christmas to all and hopes for a much better New Year.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 25 Dec , 2020, 04:39
Merry Christmas https://www.youtube.com/watch?v=J_Ucuu-doao (https://www.youtube.com/watch?v=J_Ucuu-doao)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2021, 00:38
Hello Mr. Tore and All,


I updated Skizzenbuch page 433 with new photo of the Schnorchel Indicator...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Jan , 2021, 14:23
Hello Mr. Tore,


My wife Maureen and I have been talking about visiting the U-995 Museum and other parts of Germany next year because some of her Asian college friends live in Germany as well. I would like to visit Berlin and get together with Mark Hessburg, and even perhaps visit Norway and actually meet first hand with my friend and colleague Mr. Tore Berg-Nielsen...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 20 Jan , 2021, 21:33
Make sure you contact Mr Paul Patrick-Schroder. A curator at U995
I believe he assisted you with the Uboat files?.
He has been very helpful to me also.
Be great to get a tour into the Tower.


But its closed at present to Covid.


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Jan , 2021, 01:17
Don.
You are welcome, hopefully the Covid 19 restrictions shall be lifted. I donated some images from U-995s life in Norway to the museum.
Regards Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Jan , 2021, 02:39
Great, would be nice to meet you Don.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 03 Apr , 2021, 23:59
Hello Mr. Tore,

I believe you have been copied on the email schnorchel discussions the past month or so with Simon. Arron S. Hamilton's book "Total Undersea War" has a great deal of info about the schnorchel and procedures. I was reading through some of what is available online (I just ordered the book on Amazon) and I have a few questions related to starting the GW Diesel engine...

1. They bring the U-Boat up to 25 meters and raise the schnorchel, then continue up to attack periscope depth.
2. The schnorchel head is above the water and then the Schnorchel air supply shut-off valve is opened and the water in the schnorchel air supply tube is drained into the bilge.
3. The internal exhaust valve is opened to enable schnorchelling and the blowing valve for the selected diesel engine is opened to direct the exhaust gases to the schnorchel.
4. The GW Diesel engine is started with air...

Now, here is where your expertise is needed:
When the GW diesel engine is running on air, how long is it before you switch over to running on fuel oil? I believe the internal air pressure in the GW diesel exhaust system will start to build up at a fairly rapid pace. Therefore, they need to monitor the exhaust air pressure, and open the schnorchel exhaust shot-off valve at the appropriate pressure to blow out the water in the schnorchel exhaust side (something like blowing the ballast tanks). I doubt if the schnorchel exhaust blowing is done while the GW diesel engine is running on fuel oil...

Q1 - How long will the GW air startup normally take?
Q2 - The book stated that the GW supercharger and the MAN turbocharger must both be turned off while schnorchelling. I thought the MAN turbo charger was constantly running?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 04 Apr , 2021, 02:53
Hello Mr. Tore,

I believe you have been copied on the email schnorchel discussions the past month or so with Simon. Arron S. Hamilton's book "Total Undersea War" has a great deal of info about the schnorchel and procedures. I was reading through some of what is available online (I just ordered the book on Amazon) and I have a few questions related to starting the GW Diesel engine...

1. They bring the U-Boat up to 25 meters and raise the schnorchel, then continue up to attack periscope depth.
2. The schnorchel head is above the water and then the Schnorchel air supply shut-off valve is opened and the water in the schnorchel air supply tube is drained into the bilge.
3. The internal exhaust valve is opened to enable schnorchelling and the blowing valve for the selected diesel engine is opened to direct the exhaust gases to the schnorchel.
4. The GW Diesel engine is started with air...

Now, here is where your expertise is needed:
When the GW diesel engine is running on air, how long is it before you switch over to running on fuel oil? I believe the internal air pressure in the GW diesel exhaust system will start to build up at a fairly rapid pace. Therefore, they need to monitor the exhaust air pressure, and open the schnorchel exhaust shot-off valve at the appropriate pressure to blow out the water in the schnorchel exhaust side (something like blowing the ballast tanks). I doubt if the schnorchel exhaust blowing is done while the GW diesel engine is running on fuel oil...

Q1 - How long will the GW air startup normally take?
Q2 - The book stated that the GW supercharger and the MAN turbocharger must both be turned off while schnorchelling. I thought the MAN turbo charger was constantly running?

Regards,
Don_
Hi Don
The switching over to fuel was a matter of experience, the starting procedure at snorting was pretty much like starting the engines for residue blowing the ballastanks while surfacing, clearing the cylinders by blowing starting air and possible water out via the opened indicatorcocks, then shutting the cocks and admitting starting air to the cylinders and when the engine revs turned dead slow you added fuel according to your experience, as the system derived from the reversible engine design this was a fairly rapid operation, a matter of seconds rather than minutes. A starting failure was not a big deal, you simply repeated the start. As far as I remember if the exhaust backpressure exceeded 0,8 kg/cm2 the reliefvalve at the engine exhaustmanifold lifted and filled the engineroom with black smoke which could be cleared quickly if one engine was running.
The MAN supercharging system was indeed  driven by the exhaustgases and not by the camshaftdrive and clutch with interlock as on the GW engines. On the GW engines you could only clutch in the Roots blower at higher loads.
You monitored the exhaustbackpressure constantly as you did not want the relief valve on the exhaustmanifold to open. 
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Apr , 2021, 03:04
Hello Mr. Tore,

Thanks for the info...

According to Aaron's book:
1. They bring the U-Boat up to 25 meters and at a very slow underwater speed, they raise the schnorchel mast/lock and then proceed to where the schnorchel head is above the water and the exhaust pipe is below the water surface.
2. They drain the schnorchel air mast into the bilge, so the front tube ready for operation.

Now, the issue is how do they blow the water out of the exhaust pipe and start the Diesel engine at the same time? The schnorchel exhaust system will be flooded back to the schnorchel exhaust shut-off valve above the deck on the starboard side of the tower. So, the schnorchel exhaust pipe is flooded.

Question - Can you blow compressed air into the exhaust system while opening the schnorchel exhaust shut-off valve, and start the diesel engine during or very shortly after the blowing process. You do not want to open the exhaust relief valve with back pressure during start-up?

Regards,
Don_


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Apr , 2021, 20:44
Hello Mr. Tore,

From Aaron...
"To the best of my understanding, based on the engineering reports and archival documents, the exhaust line remained, generally full of water. To what extent I do not know. The backpressure generated by the diesel engines kept the water at bay as the exhaust gasses were expelled. This is why it was so very important to close the shutoff valve at the end of snorkeling otherwise the water flushed back to the engines, forced toxic gasses into the engine room and could flood the engines."

Some of that doesn't make sense... If you stopped the diesel engine and failed to shut the schnorchel exhaust shut-off valve, then you could flood the engine. However, I don't see the toxic gasses into the engine room under that scenario.

Starting the Diesel engine for schnorchelling:

I imagine that you keep shut the external diesel exhaust valve, drain and open the internal diesel exhaust valve, and open the main exhaust valve (port or starboard) for blowing. Now, we have air filled pipes up to the schnorchel shut-off valve. At this point, you are setup for blowing the schnorchel exhaust mast that is full of water (about 8 meters high).

If we start the Diesel engine on air and monitor the exhaust pressure gauge for blowing the ballast. When the pressure gets to .5 kg/cm2, we open the schnorchel exhaust shut-off valve and switch the diesel engine to fuel (Start). Then bring the engine up to speed while clearing the schnorchel exhaust mast of water. Hopefully, when the hot exhaust gases hits the compressed air and it expands in the exhaust pipe system, it push the water up and out of the schnorchel mast exhaust pipe, and not cause exhaust safety valve in the diesel room to open...

Does this sound reasonable?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 11 Apr , 2021, 05:35
Don. There are many alternatives when omitting to do obvious things  as well as doing wrong things. The snorting system introduced at the end of the war was designed making use of the existing systems. Hence the snort/exhaust system was connected as much as possible to the exsisting system e.g. by a valveconnection to the drain chambers between each main/internal exhaustvalves. This means that the snort exhaust pipe could be drained by the original exhaust system drainage down into the bilge and pumped overboard. This would of course not imply filling the engineroom with black smoke (exhaust.) The main reason for getting exhaustleakage into the engine room with exhaustpressure exceeding the preset relief valve adjustment (mainly 0,8 kg/cm2) on the exhaustreciever. In rough weather you could of course dip the top exhaust outlet that much causing the reliefvalve to open( happened to me a couple of times).     I rather would drain the system the normal way if time allowed.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Apr , 2021, 01:23
Hello Mr. Tore,

Did you raise and lock the schnorchel mast while on the surface, and then dive to schnorcheling depth?

Or -

Like Aaron discussed; They brought the U-Boat up to 25 meters depth and raised and locked the schnorchel mast, and then went up to schnorchelling depth:

1. The schnorchel head was above the surface, but the mast was filled with water. So, they drained this water into the bilge (problem solved), and now the schnorchel mast air intake section is cleared.

2. The exhaust pipe on the schnorchel mast is below the surface. So, they can not just drain the exhaust pipe because it would continue flooding with sea water (problem)? Somehow, they had to blow the water from the schnorchel exhaust section of the mast ahead of the schnorchel exhaust shut-off valve...

Under Aaron's scenario, how did you start the diesel engine and blow the schnorchel mast exhaust pipe clear of water?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Apr , 2021, 07:59
Don.
 I really don`t remember raising the snortmast at 25meters nor to have seen  any indication in the german orderbooks mentioning such a maneuvre. We frequently raised the mast surfaced for service with no trouble.
Point 2. in your question draining the exhaust mast.  The exhaustpipe of the snortmast is connected via a shutoff footvalve to the exhaust blowingsystem and utilizes the two exhaust pipebranches ( port and stb) for residue blowing from the chamber between the outer and inner main exhaustvalves. This complicated watercooled valve casing is described in your Skizzenbook. As mentioned,  the chamber is enclosed by two valvedisks and hard to get watertight due to carbon formation on the valvesatings,hence a rotating valvdisc is provided, further the outer main exhaustvalve  is a flapvalve used for backpressure adjustments during residueblowing of the main ballast tanks. When the snortexhaust pipes are connected to this system it is connected to a fairly large internal drainage system operated by the large main drain pump in the controlroom. As we have discussed before, a massive intrusion of water in this system can be gravitydrained from the exhaust valvecasing chamber into the engineroom bilge before getting to the exhaustmanifold of the main engine, even this manifold has a substantial drainage capacity to the bilge before the water might enter the cylinders of the engines. Finally, getting water into the engines is not a disaster as we have discussed previously. Allowing water in and out of the submarine was a routine. Large and long half filled vessels could create a non desireable surface effect.


Tore


Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Apr , 2021, 00:20
Hello Mr. Tore,


If there was an exhaust leak and some of the water backed up into the exhaust Manifold, then where is the valve located on the GW Diesel engine to drain the water? Is that drain valve located on Plate 15?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Apr , 2021, 10:21
Don.
I don`t think the drainvalve is located on plate 15 as that is the starting air supplysystem. I don`t remember but guess it could be one of the valves indicated on plate 13 may be one of the valves having a sightglass. As mentioned the snortsystem were installed by the German navy latter part of WW2, at that time they were short of everything and the snorting system was designed pretty simple utilizing exsisting systems as much as possible hence existing airducts and exhaustblowing system were used. The exhaust system utilizes the exhaust blowing system going from the chamber between the outer main exhaust flapvalve and the inner main exhaust flapvalve continuing by the two pipes (stb and port) to the exhaust ballast tank blowing panel eg. 8 valves outside the pressurehull. The valves have elongated valvestems down into the controlroom. After this valvechest  the pipe continues passes a shut off footvalve operated from the controlroom and up the snortmast having outlet well below the ringfloat air intake valve.
You don`t clear the water in the snortmast exhaust system by blowing HP air but drain the mast by one of the drainvalves in the aft engine room, I don`t remember which but possibly the pipe with valve and sight glass.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2021, 01:59
Hello Mr. Tore,

I believe that valve (n) is used to drain the exhaust manifold of flooded seawater into the bilge, and the safety valve is to the right of it on Plate 15.

I had a wrong label on the large funnel and corrected it as "Drain into Bilge."

What do you think?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2021, 02:02
Don.
Checking the other plates 13 I figured out the plate 13 for the GW engines have wrong letters for several valves like valve p becomes o hence a wrong and confusing  naming and purpose of the various valves in the system.Below is a correction which might clear up the matter.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2021, 02:10
So, in order to drain the exhaust manifold you will need to open the venting valve (n) and the Drain valve (o) on the exhaust manifold...


Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2021, 02:33
Don.
I guess the venting valves belongs to the anticorrosion system. E.g. you are draining the seawater in the coolingmantels. We did not make use of the anticorrosion system and had only minor problems.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2021, 02:42
Hello Mr. Tore,


I guess where my confusion begins about the cooling water system involves the jacketing of the exhaust manifold. Some of the draining valves are taking water and possibly some air from the cooling water jacket space. However, the vent and the drain for the exhaust manifold has to pass through the water cooling jacket to the inner chamber of the manifold in order to function properly.


Therefore, valve (n) the vent valve line, the safety valve line, and the drain valve (o) line must pass through the water cooling jacket into the exhaust manifold chamber in order to function properly...


What do you think?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 16 Apr , 2021, 03:08
Don.
This is only for draining the sea cooling mantels in the system not the possible seawater from the leakages of the main exhaust flapvalves. In a confined space like the coolingmantels you need a vent to be able to drain properly.
Below is an image of the reliief valve of the exhaust reciever, as you see pretty close to the maneuverstand and could be unpleacent for the man operating the engine.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 16 Apr , 2021, 18:35
Hello Mr. Tore,

I have the same view of the Diesel engine that you have item listed the components in your previous posting. However, with the magic of the Paint.net application, I can bring some components to light! Could what I have uncovered be the components in Plate 13 that I had marked as well? The lower handle looks like a black "L" shaped handle and the drive shaft extends under the diesel engine exhaust manifold end cap near the operator.

Regards,
Don_


Addition:
If you look at this drawing that you had done several years ago (last posted). The exact same valves are identified as the vent valve (n) and drain valve (o). However, I believe these valve actuators are located near the safety valve at the forward end of the exhaust manifold, and not in the relative position as shown in the schematics.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 19 Apr , 2021, 14:11
Hello Mr. Tore,

The top valve in my previous posting looks to be a cooling water drain valve per Simon's drawing (see the red circle)...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 20 Apr , 2021, 03:31
Hello Mr. Tore,


Do you have a photo of what valve is connected to pipe #7 on the u-historia photo?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Apr , 2021, 01:53
Don
I have been looking into my files and the only I found is the image below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Apr , 2021, 02:38
Don.
Somehow the lower part  of my image was cut off. Here is another try.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Apr , 2021, 03:20
Hello Mr. Tore,

I didn't realize that U-historia has two #7 items listed...  I took one of Simons drawings and it looks like the line in "Yellow" drains the the Main internal exhaust valve chamber of flooded seawater???

I was just attempting to get that established...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 21 Apr , 2021, 07:25
Don,
I leave it to Simon to comment on his drawing, but guess you remarks on draining the snortmast and startig is correct with a few minor things. Basicly the starting procedure is the same as for any start. As you normally shall have some water in the chamber between the outer and inner main exhaustvalve. However if you have a massive intrusion of water you might experience a filling of the exhaustmanifold with a possible filling of some cylinders as you have explained. In any start you blow through the cylinder with open indicators cocks and the engine shall turn a few revs, you don`t  open the indicatorcocks to "make it easier to turn the engine", the reason is to blow out possible water in the cylinder through the open indicator cocks to prevent waterstroke. The starting airpressure of 30 kg/cm2 is ample to run the engine easy on air only, but you want to prevent water strokes, hence you want to get rid of the water in the cylinder which might created a major damage by a reciprocating engine. Only in extreme cases you crank the engine by hand, not normally, as air shall do the job easy having an experienced engineer at the starting handle bowing out the trapped water in the cylinders flooded.
I noted some place you mentioned we dived with the snortmast raised, that is a misunderstading, we normally raised the snortmast submerged but raised the mast for maintenace surfaced, see the image below, however we did we never run the engines with the mast raised on the surface as the mast did not have any cooling and the greaseingpoints could be ruined.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Apr , 2021, 15:28
Hello Mr. Tore,

Thank you for the corrections...

#1) Starting the Diesel engines with controlled air pressure makes perfect sense (The only cylinders that should be flooded with seawater had their exhaust valve open when the Diesel engine was stopped - flooding occurred via the cylinder head exhaust chamber and the exhaust manifold seawater intrusion)...

1. HP air is admitted on a piston in a power stroke (drives it down the cylinder liner & turning the crankshaft).
2. Any piston in the exhaust stroke will force any seawater out of the liner via the open exhaust valve.
3. Any piston in the intake stroke will take in pressure hull air via the open intake valve.
4. Any piston in the compression stroke will force air out through the open test cock.

After the first 2 full turns of the crankshaft there should be practically no more water in the flooded cylinder liner depending upon the flooding state of the exhaust valve chamber in the cylinder head. Eventually, all flooding water will be forced into the exhaust manifold with HP air and drained into the bilge via the open drain valve...

#2) OK... You raised the schnorchel mast submerges as Aaron suggested. So, you had to drain the Schnorchel mast air supply section into the bilge to clear the water and open up the air supply.

The schnorchel exhaust mast is still flooded up to the tower deck exhaust shut-off valve? U-995 had the Type II schnorchel with the bend in the air supply, and the straight connection from the schnorchel exhaust shut-off valve and through the blowing valve and then to the Main External Exhaust Valve. The exhaust system on the Type II schnorchel doesn't seem to have a draining capability? 

This was the question that I was attempting to understand... What was the starting procedure to deal with the flooded schnorchel exhaust system at the schnorchel exhaust shut-off valve?

Regards,
Don_

I thought that just starting the Diesel engine on air like normal, and when the internal exhaust system got up above 0.5 atmospheres (like blowing the ballast); then opening the Schnorchel exhaust shut-off valve and switching to fuel oil (ignition)?

However, Aaron has documentation of a special HP airline attached to the exhaust manifold to blow the schnorchel exhaust mast...
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 22 Apr , 2021, 00:38
Don.
The snort exhaustpipes have indeed a draining capacity as they are connected via shut off valves to the drainchamber between the inner and outer main exhaustvalves port and starboard. When draining the raised snortmast you can open one of these shut off valves and drain the water into this drainchamber and you have a normal situation like a leaking outer main exhaust flapvalve, hence you drain the water in the drainchamber to the bilge and discharge it overboard.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Apr , 2021, 13:42
Hello Mr. Tore,

I agree that the drain capacity is there as you described... However, the schnorchel exhaust pipe outlet is about 0.5 meters below the seawater's surface level. You can drain the schnorchel's exhaust mast all day and never empty it because it will constantly be refilled by the surface water! Therefore, the Schnorchel's exhaust mast must be blown and then start the Diesel engine immediately to maintain the opened exhaust capability with the exhaust pressure...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 22 Apr , 2021, 14:58
Hello Mr. Tore and Don
Hope you are all well?
During my research, I noticed these brackets.
I have asked this question recently on some Uboat Facebook sites and even the curators of U995 are unsure as to what these brackets on U995 were used for.
I have identified 3 of them so far onboard U995 from pictures, one under the Switchboard, one in the Galley, and One in the Forward Torpedo Room. There may be more I haven't found as yet.
No one is 100% sure if they are Kriegsmarine or Norwegian add ons.


And I see on my U570 Photo that there is NOT a bracket, although U570 Switchboard is early war Round type and U995 is late war Rectangular.


Some suggestions have been


1.Original Fire Extinguisher holders, either Kriegsmarine or Norwegian,  although they seem a bit small
2.Flashlight holders, although the Kreigsmarine Flashlights were generally square shaped.
3.Filters or spares holders
3.Crew Emergency Oxygen holders.


Can you shed any light on this mystery bracket at all?
thanks
Raymic (Mike)
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Apr , 2021, 02:15
Hello Mr. Tore,

I agree that the drain capacity is there as you described... However, the schnorchel exhaust pipe outlet is about 0.5 meters below the seawater's surface level. You can drain the schnorchel's exhaust mast all day and never empty it because it will constantly be refilled by the surface water! Therefore, the Schnorchel's exhaust mast must be blown and then start the Diesel engine immediately to maintain the opened exhaust capability with the exhaust pressure...

Regards,
Don_

Don, you are absolutely right, I have no excuse but the brain of an old man now going on 94. Back to the drawingboard. Have you seen the German instruction on the orders for raising the mast of 1944? It is unfortunately in the german luangage but gives a good impression how the Germans operated the snortmast . I have briefly read it  with my rusty german knowledge, but as far as I can see they raised the mast submerged, ascended up to periscope depth, ( not mentioning which periscope) prepared the engines for start by starting the luboilpumps, normally blew through the engines a few times. Then at pericope depth they drained the airmast prior to starting the engines carefully while opened the snort mastexhaust valve monitoring the exhaustgaspressure not to exceed 0.8 atm. I am mailing the font page of my document which I have only breafly scanned. By this procedure they are using the engines blowing out the snortexhaust mast with narrow margin as to max exhaustpressure . In this detailed document  there is no metioning of blowing the exhaust mast with HP air, it seems they simply used the diesels at low load. May be worth while to check further, I guess some of our german friends might be able to translate the document.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 23 Apr , 2021, 23:21
Hello Mr. Tore,


Perhaps we could ask Mark Hessburg to translate the document...  I tried, but the scanned copy is really difficult to read...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Apr , 2021, 01:05
Hello Mike,

Sorry about not getting back to you earlier...

My best guess is that your first thought as those being fire extinguisher brackets sounds about right. The big red ones throughout the U-Boat are not originals by any means. Just put there during modern times for insurance regulations and tourist protection.

I don't see those brackets in the Control room, the NCO's ward room, Officer's ward rooms. The Diesel room may have its unique fire control system; you need to ask Mr. Tore about that situation. However, the forward and aft torpedo rooms contains explosives, and the E-room could have an electrical fire. As far as the Galley is concerned, the cook could have a bad day and set something on fire...

I searched the internet for WWII German fire extinguishers and her is what I found. They look like they could fit into those brackets...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 04 May , 2021, 11:33
Hello Mr. Tore,


Do you have any information about the Supercharger clutch and the linkage that activates it? I found it on one of your drawings and would like to understand that part of the GW Diesel engine...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 May , 2021, 09:10
Don,
As you know the U 995 was originally designed to be propelled by direct reversible GW engines hence the linkage with clutches are originally equipped with a number of interlocks no more applicable. Below is an image of the system where I have removed the superfluous reversing rudiments. The GW engines were as you know designed with a Roots blower pto from the camshaft and should be switched in at 390 rpm. The drive is shown on the image below. At a normal start the supercharger is disengaged. On the both engines there are two manifolds towards boardside, the upper for airinlet, the lower watercooled, for outlet. The outletmanifolds are connected via flanges to the cylindercover exhaustducts (with exhaust cages, watercooled). The airmanifold has flangeconnections to the separate airinlets in the cylinder cover. Further the air manifold has two inlets which can be shut by cylindrical slidevalves operated by the supercharger clutchhandle up front of the engine and to the Roots bloweroutlet, thus now an enclosed airsupply to the cylinders..
If revs are required above 390 the fuelfilling handle is pushed to a higher fuelfilling position, the supercharger clutchhandle at the outboard side pushed rotating the rod by bevelgear. The rotating rod continues after the air shutting valve where the rod is fixed to a 90 degrees bevelgear transferring the rotation to a rod with gearwheel which is engaging a tootrack, which is axially moved and thereby trigger the friction shoe of the friction clutch. 


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 05 May , 2021, 13:21
Hello Mr. Tore,


The finer detail... Is this how it works (see the attached drawing)?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 08 May , 2021, 12:42
Hello Mr. Tore,


I got a drawing of the supercharger clutch and now see how it works...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 May , 2021, 21:39
Hello Mr. Tore,

I came across this drawing of the Supercharger and it looks like the input air is run towards the outer casing. I guess the air vents on the outer casing is adding a cooling effect to the compressed air fed to the Diesel engines intake manifold and the cylinders...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 May , 2021, 05:36
Don.
In supercharging mode the inlet air enters towards boardside as the main dieselair outlet . The main dieselair shaft ends down towards the bilge is draining seawater mixed with air to the bilge, creating an impressive splash whereas the combustion air shaft on air intakes both for the normal aspirated and supercharged mode are situated a bit higher up and well apart from the dieselair duct outlet. I am afraid the arrangement do not allow for any "intercooling" effect. In spite of the arrangement we experienced salt deposites on the Roots blower rotors jamming same and we had to dismantle the blower for cleaning. My personal opinion is that in extreme weather the dieselairshaft was occasional flooded via the valve in the towercasing causing a massive intrusion of seawater mixed with air which eventually entered the air inlet of the supercharger, the seawater evaporated during the compression in the Rootsblower and left the deposits in the blower. Cleaning the blower was a 12-14 hours job[size=78%].[/size]
Tore   
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Jun , 2021, 00:22
Hello Mr tore,

When you experienced the Roots Supercharger jamming because of sea salt on the impellers or in the air chamber what broke? The supercharges is gear driven from the Diesel engine crankshaft. I would think it would be the impellers were damaged because the Diesel engine is turning at around 2000 RPM when the supercharger clutch was engaged (possibly the clutch was damaged too) ???

Interesting...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 01 Jun , 2021, 02:18
Don
When you clutched in the Roots blower you noticed very clearly the frictionclutch started slipping and smoking so you declutched immediately. No dammage was done to the clutch or geartransmission (camshaftdrive)
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jun , 2021, 01:52
Hello Mr. Tore,

I guess that I'm starting to forget things....  I have been looking over some drawings from Crushdepth.com and the mechanical hydroplane indicators are using the Telekin System. I thought that we had discussed this topic but I don't remember Telekin name???  What did we use years ago?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jun , 2021, 04:44
Don.
I guess the system is called Teleflex.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 14 Jun , 2021, 23:17
Hello Mr. Tore,

Do you have any documentation that states when the grinding of the exterior exhaust valve seats changed from a manual hand-wheel operation to the pneumatic motors. It looks like the Type VII B U-Boat was only a manual grinding operation.
 
1. Was the pneumatic grinding motors part of the upgrade to the Type VII C?   
2. Was the pneumatic grinding motors an upgrade to the Type VII C at a time later?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jun , 2021, 00:52
Don.
Sorry, I have not any documentation as to the fitting of the pneumatic grinding of the outer main exhaust flapvalve. I doubt this was a feature of the VIIC/41 only, as both of our remaining VIICs (not 41) were equipped with same.
A disadvantage with the Pneumatic grinding was in the event of the need for a longtime grinding, the internal air pressure in the sub increased and some time we had to start the E-compressor to lower this pressure.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Jul , 2021, 17:32
Hello Mr. Tore,


This photo is of the bulkhead inside the forward torpedo room...  Do you remember what would be located at the red circled location?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2021, 03:14
Don.
Sorry I cannot remember, to me it looks like a bracket for a gyro repeater, a lot of stuff were mounted on this bulkhead particularly electronics related to Nato surveillance after my time. The small hooks up on the top of the image were hooks for the brigde rain coats to be dried.

Tore.

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Jul , 2021, 09:33
Don.
Returning to your question of today I am posting an U-Historia image of the equipment hooked up to the item you questioned. As you see it is indeed more to it than just a bracket and as I assumed related to surveillance installed after my time. I guess everything of this installation is classified and removed.

Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 04 Jul , 2021, 22:21
1.Mr. Tore..was there supposed to be a U-Historia picture attached?


2. Ref the original inquiry, there is at least 3 of these White Circle mounts on U995.
Attached is a picture from the Rear torpedo room one, above the Electric Compressor.
There is also an electric wire that runs into the back of each of these  'White Circles'

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 05 Jul , 2021, 01:58
Raymic1
Sorry somehow my U-Historia image was not posted hope my second try works.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Jul , 2021, 02:25
Hello Mr. Tore,


I have a question about roll stability with the Type VII C U-Boat:


1. When FBT 2 and FBT 4 are in the fuel oil configuration, the U-Boat sets lower in the sea water and this would add to the roll stability because the center of gravity is lower compared to the water surface. Therefore, the U-Boat has a degree of roll stability.


2. However, when FBT 2 and FBT 4 are in the water ballast configuration, the U-Boat sets a little higher and the water line is raised. But, FBT 2 and FBT 4 empty tanks also provide stability against rolling.


Is one state better than the other for roll stability, or are they about the same?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jul , 2021, 05:26
Don.
 Sorry about my late answer, I have just returned from my summerfarm where the access to the net is limited.
The transvers stability of a submarine is a bit complex and consist more elements than saddle tanks and fuel, in general you might say it has many variables as follows:
 1. Stability on the surface where the submarine acts like any surfaceship and the stability is governed by the metacentric hight.
 2. Stability submerged where the submarines transverse stability is created by the distance of the submarines center of gravity and center of boyancy. A proper way of obtaining transverse stability is placing heavy equipment between the submarines center of gravity and center of boyancy. A proper stability is achived by by putting heavy equipment like batteries as low as possible.
 3.The complicated stability while breaking the surface when the metacentric hight reduces, hence the tranverse stability as you ascend and break the surface. The COs normally like to have a check on the wind and waves to put the submarine in the right position as you break the surface  when the tranverse stability is low. I have experienced excessiv heeling of more than 45 degrees during surfacing. As far as I remember the batteries could take 60 degrees before spilling acid.

     Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 13 Jul , 2021, 20:34
Hello Mr. Tore,


Which state would you consider more roll resistant with a U-Boat Type VII C on the surface:
1. U-Boat in fuel oil reserve mode with the saddle tanks full, the U-Boat is about 9 inched lower in the sea as is the center of gravity.
Or
2. U-Boat saddle tanks in the water ballast configuration, and the air filled saddle tanks on the side of the pressure hull resisting the roll motion.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 15 Jul , 2021, 07:48
Don.
As mentioned before a submarines transveres stability has many variables and saddletanks introduces many more, without going into the metacenctric hights and naval architects math. you may say filling the seawater compensated saddletanks with fuel introduces a rise of the submarines center of gravity and weight, this shall normally reduce the transverse stability. With the saddle tanks filled with air and no water creating surface effect the submarine looses weight and the center of gravity sinks, hence the stability increases.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jul , 2021, 02:56
Hello Raymic1,


Paul "TheEngineeringGuy" on the CrushDepth Website discovered that the plates were for a mechanical clock. I tend to believe this is true because to the three (3) mounting holes. Also, The clocks were the first thing to be pilfered from the U-Boats after WWII...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 24 Jul , 2021, 04:20
Thanks, Don for the clocks. Very interesting.


I also took this still from a video on FB off a Fort Aniota Museum at Fort Zachodni Poland.
It looks like a Mergus-type Uboat Toilet but is not as complex.?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 24 Jul , 2021, 04:34
Also in regards to the clocks. Here is a close-up view of the back of the circular plate in the rear Torpedo room.
You can see some sort of electrical wire or pneumatic cable going into the back of it. So possible the clocks were powered either this way?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 24 Jul , 2021, 13:30
Hello Mike,


I believe that view of the back of the mounting plate is a bit misleading. This front view of that plate does not show any hole towards the center. Besides ,the U-Boat clocks were key wound as you can see on the clock face just above the 6 in the photo that I previously posted...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 24 Jul , 2021, 15:00
Yes your right. A bit of parallax in the rear pic....
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Jul , 2021, 05:56
Being immobilized for a few weeks due to the gout made me some sparetime to re-arrange my e-painting of KNM Kaura, ex U 995. It is pretty much the same image as previously published. A fiction of KNM Kaura in the Vestfjord, Northern Norway, above the artic circle, where we usually were patrolling, escorted by a group of killer whales while passing the lighthouse Kaura (where KNM Kaura got its name from) and the old steamer S/S Finmarken (the lifeline to the rest of the world). The image is a fiction from 1953, part of it published in 2017. Might be some of the present days follower haven`t seen it.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Jul , 2021, 04:40
Hello Mr. Tore,

I got the Gout about a month ago and my doctor gave me a 10 day prescription for Prednisone (A steroid) which resolved the painful problem... I get a severe case of Gout about 2 - 3 times pre year.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 30 Jul , 2021, 05:03
Don
Same thing here, but the last attack lasted 4 weeks, I am OK now.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 21 Sep , 2021, 17:35
Tore, Rob Brassington, who created this awesome animation, is looking for information about the mechanism of the torpedo tube. The video shows his level of knowledge or simplifications for lack of better knowledge. Maybe you see things that should be different?


https://www.youtube.com/watch?v=CAO2BYZdfE4
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Oct , 2021, 04:03
Hello Mr. Tore,


Do you remember where this valve chest is located in the diesel engine room?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Oct , 2021, 05:45
Don.
This valvechest is situated right underneat the writing deskplate port frontbulkhead in the engineroom.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Oct , 2021, 21:08
Hello Mr. Tore,

I can see the valve chest for the Lube Oil located below the Desk Plate, but I can't locate the valve chest for the Fuel Oil in that area...

Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 18 Oct , 2021, 03:01
Don.
As you know the aux. luboil pump could be used as an emergency fuel transferpump. This function was not likely to be used frequently and the connection to the fueltransfersystem was not as easy accessible as the aux. luboilpump function ( Used prior to every turning and start). I personally never used the aux. luboilpump as a fueltransferpump but as far as I remember the connectionvalvechest shown on the plate 9 was situated under the floorplating between the main engines hence not visible on the immage. If you look at the fuelpiping in and out of the fueldaytank (setlingtank) and on the front of the engines you have an idea of the considerably smaller pipingdimension.
Tore

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 18 Oct , 2021, 12:37
Hello Mr. Tore,


Thank you for the update and information. I believe Patrick will goto U-995 and attempt to get a photo of the Fuel Oil Valve Chest... He has been helping with the restoration and has unusual access to U-995.


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 30 Oct , 2021, 14:58
Hello Mr. Tore,

Can you verify if the market valved are the Fuel Oil Valve Chest?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 31 Oct , 2021, 03:05
Don.
I don`t think these valves belong to the fuel transfer system, hard to see the detail but I guess they are valves belonging to the ordinary luboilsystem.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 01 Nov , 2021, 13:24
Hello Mr. Tore,

FYI... You are correct about those valves belonging to the lube oil system...

It looks like the fuel oil pump was the easiest pump to replace, them the lube oil pump, and lastly the water cooling pump. How much time did it take to replace each of the three (3) pumps?

What was the failure mode for the fuel oil pump; It is gear driven and is well lubricated with fuel oil? I would think if a screw or nut got past the filter and jammed the pump gears, then an intermediate drive gear would have a shear pin so that nothing in the diesel engine side would be damaged. Was there an issue with the pump just wearing out and what usually broke?

I have the same questions about the lube oil pump and the water pump???

Regards
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2021, 02:31
Don.
Your questions might be unclear to some as it covers a lot, like fueloil-, lubeoil- and coolingwater systems, including the components, their maintenance and alternative operation. I guess it would be easier to split up the questions referring to each system separately. A full basic understanding of the discussed system is vital. Generally all systems have a number of alternative operationsolutions and sometimes you had to use your creativety and study the system plates to figure out which solution to use. No book could tell the optimal solution for every situation, experience and creativety of the engineroom crew had to be used.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 02 Nov , 2021, 13:22
Hello Mr. Tore,

Basically, how much time would be required to change out the Fuel Oil Pump, the Lube Oil Pump, and the Water Pump. If one (1) of these three (3) pumps were swapped out after a failure, then what was the main reason for the failure as observed during your service on U-Boats...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2021, 15:13
Don.
A HP fuelplungerpump, driven by the camshaft, 11/2-2 hours, the attached fuel supply pump, driven from the crankshaft up front 2-3 hours, the fueltransferpump electrically driven vertical IMO type trippel screwpump 8-9 hours. Hour estimations assuming sparepump available, apart from the camshaftdriven HP fuelpumps  normally no complete pumps stored on board. We had a few seized HP plungerpumps otherwise we did not have much trouble with the fuel/lubeoil pumps.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 02 Nov , 2021, 15:27
Don.
The electric driven coolingwater pump did not give us any trouble, however on the attached piston coolingwater pump the conrod of the piston broke and smashed the cylinder. The pump is situated very low with difficult access up front of the mainengine and could not be repaired by us. Same pump was repaired at the submarine baseyard.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 03 Nov , 2021, 06:14
The flexibility of the various system. As I have mentioned before the systems have been designed for many alternative solutions left to the engineroom crew skills, experiences, and creativity to utilize. One important feature is the aux. luboilpump function as a fueltransfer pump. Being able to bunker fuel from any sources might be vital. This is a detailed description of one solution of many.


Bunkering fuel utilizing the aux. lubeoil pump.
One of the aux. lubeoil pumpoperations is pumping fuel from a source not capable of of supplying fuel with sufficient pressure. Referring to the plate 9 below it goes as follows:
 In the casing is a hoseconnection leading to a fueloil pipe which enters the pressurehull via a hullvalve (a). The pipe, marked dotted green, enters a nut and bolt filter and continues to a suction inlet in a valvechest underneath the writing plate on the forward portside engineroom bulkhead.
In the event of bunkering fuel from a source not capable of supplying fuel against the head of the watercompensated fueltanks the aux. luboil/fuel pump suction is connected  to the suction connection b2. on the valvechest and the pump discharge the fuel into the chest pressurechamber via valve b1. By opening valve valve c in the chest the fuel continues to a filter before a fuel meter. Then the pipe return to the valvchest via cock e and leave the chest by opening valve b6. then via  a bypassfilter before entering a selector cock e1 which makes it possible to select port , starboard or both daygravety tanks which then can be topped up. From the selected gravety tank the fuel passes a fuel meter, a branch off to the Junker compressor to a 3 way cock in a crossover pipe to the suction of the engineattached fuel supply pumps port and starboard. In spite of the plate 9  the GW engines these pumps are driven from the crankshaft up front of the engines. From the supplypump the fuelpump deliverypipes goes to a finefilter on the top of the camshaftcasing the filter is not shown on the plate 9.
By using the same methode you are able to bunker any internal fuel tanks as can be seen on the plate 9.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Nov , 2021, 05:24
Hello Mr. Tore,

I believe valve (k) is an overpressure device to limit the fuel oil pressure to the injectors. If one of the diesel engine's fuel oil pumps failed, then you could use compensation water pressure from any external tanks, or the Auxiliary Fuel Oil Pump to provide fuel oil to the injectors by bypassing the failed pump using the internal fuel oil tanks. Also, while using the compensation water pressure or the Auxiliary Fuel Oil Pump with a failed fuel pump the day tank is bypassed...

My question is: When you bypass the failed fuel pump and provide fuel oil pressure to the injectors on that diesel engine. However, the engine with the functional fuel pump will see the increased fuel oil pressure at the pump's head. Does valve (k) just feed back any excessive pressure to the pump head, or do you have to bypass both fuel oil pumps to avoid an overpressure situation on the functional fuel oil pump?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 06 Nov , 2021, 08:10
Don.
As the fuel centrifuge was discarded, great care is taken to prevent accidental mixing of fuel and water, hence the double daytank has two purposes 1. Being a buffer placed as high as possible in the engine room to provide suctionhead to the engineattached fuel supply pumps, which are positive displacment pumps.  2.  acting like a settlingtank by being a double tank able to settle and drain the impurities in the tank not in use.
Generally all positive displacementpumps have, contrarly to sentrifugalpumps, a reliefvalve intergrated returning the liquid from the discharge to the suction side to prevent dammage in case accidental shutting the discharge.
The HP fuelplunger pump for each cylinder is a positive adjustable displacement pump having supply from the engine attached supply pump, but  would be able have positive fuelsuctionhead by the highly placed fueldaytank in case of failure of the engine attached fuelsupply pump. The daytank capacity of 700 litres would be able to serve both engines in the highly unlikely event of both fuepsupplyumps would fail.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Nov , 2021, 02:22
Hello Mr. Tore,

Are you telling me that all of these scenarios will work?

1. Both fuel oil supply pumps failed and fuel oil will be supplied by one side of the day tank and because of the height of the tank (head pressure) above the bypassed fuel oil supply pump and on to the injectors. I thought there was a problem with the low head pressure from the day tank (i.e., The main reason for the fuel oil supply pump)?

2. Both fuel oil supply pumps failed and fuel oil could be supplied from any external fuel oil tank. The pressure head would be fairly high. The fuel will bypass the day tank because the valve is set in the pass-through position, thus providing adequate fuel pressure bypassing the failed pumps and on to the infectors. 

3. Both fuel oil supply pumps failed and fuel oil will be supplied from an internal fuel oil bunker via the Auxiliary Lube Oil Pump going through the day tank selection valve set in the pass-through position and bypassing the failed fuel oil pumps and on to the injectors...

Regards,
Don_

FYI - From Skizzenbuch page 73 - "If the attached fuel oil gear pump failed and must be by-passed; the pressure head from the gravity tanks height above the diesel engine (image below and less than 2 m WC) is probably not sufficient to force fuel through the filter and supply pipe to the high-pressure fuel injection pumps. Hence, you use the full compensating water pressure from the header tank (some 5 m WC) to provide the needed pressure. The compensating water pressure head goes directly to the fuel injectors supply pipe and by-passes the gravity tank."
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 07 Nov , 2021, 05:34
Don.
The fuelsupply pump can be bypassed by the cock e but have a  knifefilter between the suplypump and the HP pumps which would cause  some resistance which might require a larger head than obtained by the daytank. I have not tested this unlikely event, but would in case of emergency have tried to connect the other engines supplypump before using the compensating water pressure to the daytank.
I am not sure I understand your next question. In case both engineattached fuelsupplypumps fails you would be able to use the separately driven fueltransferpump via the day tank.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 21 Nov , 2021, 13:15
Hello Mr. Tore,


While we are still looking for the fuel oil valve chest under the floor plates, Patrick in Germany came across the brackets outlined in the attached photo. Do you remember what was attached?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 23 Nov , 2021, 07:59
Don. I cannot remember in spite of pondering for a couple of days.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 23 Nov , 2021, 20:01
Don
Just wondering. Are you working with Paul- Patrick Schroder or a different Patrick at U995?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 26 Nov , 2021, 19:45
Patrick Salmen who has a great collection of digital copies of original U-Boat manuals and documentation. He seems to get good access to U-995 and does some volunteer work.


Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 10 Dec , 2021, 02:27
Patrick Salmen who has a great collection of digital copies of original U-Boat manuals and documentation. He seems to get good access to U-995 and does some volunteer work.


Regards,
Don


Ah OK. I thought it might be Patrick Bateman The Engineer Guy, he also has a lot of original U-boat docs that haven't been published yet.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Dec , 2021, 18:50
Hello Mr. Tore,

Since 2018 when I released Skizzenbuch, there were 3 websites that I authorized the book's distribution: AMP, The Subcommittee, and Wehrmacht Awards. The latter 2 were able to provide me with a download count, and there was a total of well over 13,000 downloads of Skizzenbuch. In addition, there were about a half dozen pirated sites in Europe and Asia that charged for a high speed download option which was a rip-off! Their initial slowed download speed was taking well over 5 hours, and the high speed download was about 3 minutes (which was about the normal speed from my Dropbox account).

About 6 weeks ago, I decided to look into doing an Amazon.com Kindle publication of Skizzenbuck in a Print Replica format; basically its like a pdf and Skizzenbuch was published on December 6th... I set the price at the minimum charge of $2.99 on the Amazon Website/Kindle Store. I doubt if the royalties will ever cover the yearly cost to maintain the Kristallklar Publishing, LLC, Corporate status in the state of Georgia, the Registered Agent fees, and the initial US Copyright cost. Here is what the Skizzenbuch eBook cover looks like (see the attachment)...

Mark Hessburg was the first person to purchase Skizzenbuch from Amazon's Kindle Store and write a review; now that's a good personal friend...

Regards,
Don_

FYI... I pulled the plug on the free Skizzenbuch download from my Dropbox account.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 25 Dec , 2021, 02:14
Hello Mr. Tore and All,


Merry Christmas and Happy New Year to All - May we all enjoy Christmas with our families and have a happy and healthy new year...


Kind regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 25 Dec , 2021, 05:23
Don.
Returning the whishes
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 25 Dec , 2021, 09:12
Merry Christmas.


U 995 Christmas snow mod:


(https://hessburg.com/pictures/Merry_Christmas_WOTA.jpg)



Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 25 Dec , 2021, 15:17
Merry Christmas!

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 11 Jan , 2022, 18:04
Hello Mr. Tore,

If you ever had a reason to look at the External Exhaust Flap Valve Casing on U-995; do you recall if it was a single cast casing or three (3) separate casings bolted together Brown/Orange/Yellow (See the drawings)?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 12 Jan , 2022, 04:52
Don.
I never checked it personally, but based on the general castings on VIICs I would assume such a complicated casting would be three castings bolted together. See image from a IXC.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Jan , 2022, 18:38
Hello Mr. Tore,

Simon and I believe that U-995 would have had the three (3) Sectioned Exhaust Flap Valve Casing because it was a Type C/41 which could dive deeper (They also applied the same External Exhaust Flap Valve to the later Type VII C's as well). So, the Germans installed a shut-off valve between the exit exhaust casing and the 1st section of the Exhaust Flap Valve Casing. The shut-off eliminated any sea water depth pressure from applying excessive water pressure on the internal exhaust water cooling pipes. Remember they did the same thing with a valve to the internal fuel tanks with regard to the compensating water pressure. I believe that Simon has located the shut-off valve in the Diesel engine room upper pressure hull. These construction changes were made to the Type VII U-Boats in the late 42 to 43 period and beyond...

Regards,
Don
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Jan , 2022, 06:56
Don.
As you know we had 3 VIICs in service U995, U-926, and U-1202 the latter 2 were VIICs. U995 is VIIC/41. As far as I remember they were equipped with the same external exhaust system. The external systems were with two external main exhaust flap valves which had a double functions
  1. The outer main exhaust valve being a shut off flapvalve with rotating valvedisk for grinding off carbon deposits on the valve seatings.  This valvedisk was driven by a pneumatic motor in the engineroom with rod extension through the pressurehull to the outer main exhaust valve.                           
 2.  The inner main exhaust flap valve being a shut off valve with a large drain to the bilge, the rotating valvedisk could be manually turned with a wrench on a stubshaft outside the valve casing.
At diving the outer exhaustvalve was shut and the pneumatic grindingmotor started, as soon as we descended through the watersurface we got a sligth back pressure on the valvedisk. When we came deeper the grinding came to a halt at some 4 meter as the back pressure  created a torque larger than the pnuematiq motor could manage. A few times this grinding was not sufficient and we drained the leakwater down to the chamber in the inner shutoff valvecasing and further to the bilges. The deeper we came the higher back pressure on the outer exhaust valvedisk. I cannot recall we ever had to surface because of this system.
When surfacing you know we used the exhaustgases for residue blowing. As there is a limit as to the back pressure the engines can take, as far as I remember the limit was 6-8m wc . This was monitored by the engineers and you had a procedure for not exceeding the back pressure. For controlling the exhaust back pressure the outer mainexhaust valve was used. The low pressure residue blowing (exhaustblowing) followed a certain sequence by starting with the highest ballasttanks and as the submarine ascends further blowing the deeper tanks. A drawback with the pneumatic grinding was the increase of the atmospheric pressure of the submarine and a few time we had to start the E-compresor to get the pressure down.
Tore 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jan , 2022, 03:13
Hello Mr. Tore,

Remember several weeks ago...  I was asking about the location of the fuel oil valve chest. Patrick came up with a photo of what looks like a possibility for the location of the fuel oil valve chest. Do these photos trigger any memories?

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 17 Jan , 2022, 07:31
Don.
 A few ideas crossed my mind. There is obviously a difference between the two internal fuel bunkering pipes, the port pipe looks like the original wheraes the starboard having a strange hull valve, the stb strainer is placed under the floorplates and look different from the originals. Having just a quick look it seems that somebody has modified the system to make it possible to bunker from the starboard casing side and  keeping the original port, why? it might be related to the original wintergarden which was removed. Below a simple sketch showing my idea of the current system.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jan , 2022, 14:38
Hello Mr. Tore,


I recall that you said that you never used the saddle tanks for fuel oil storage because you always had access to coastal fuel oil supplies. Did you use Regulating Tank No. 1 for fuel oil, or only the internal fuel oil tanks?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 17 Jan , 2022, 15:52
Hello Mr. Tore,


It looks like the Germans changed the fuel oil side access. The first drawing is from U-570 launched in 1941, and the second drawings is from 1943 (They changed the fuel oil access side)...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 07 Feb , 2022, 22:27
Hello Mr.Tore,

Patrick came up with a photo where it looks like the Fuel Oil Valve Chest is located under the step coming into the Diesel Room. Does this photo refresh your memory about the location of the Fuel Oil Valve Chest located between his feet?

Regards,
Don_

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 14 Feb , 2022, 04:08
Don,
To me it looks like it might possibly be the valveconnection to luboil storage tank 1 and 2.


Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 15 Feb , 2022, 01:54
Hello Mr. Tore,


Below is what I was thinking...  Your Opinion?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 12 Mar , 2022, 15:10
Hello Mr.Tore,

Question from Patrick....  Do you know what this is? It's directly behind the speed indicator. Is this part of it? I have seen it on many boats. On the right we have a IX Type Which haves the same.

Don_

It looks like it's a drain for the speed meter to drain any air from the speed measuring system because the air could compress and cause an incorrect speed reading...

Am I guessing correctly?


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: tore on 13 Mar , 2022, 10:36
Don, I guess so, On U 995 the pipes for the dynamic pressure which belongs to the Pitot log has its two inlets below the water line on port and stb side of the bow and the static inlet is at the fwd. end of MBT 3. Both pipes goes to the log box on the front of the control next to the fwd hydroplane operator where the speed is calculated and transferred as an electric signal to the repeater in the conningtower. I have a blurred image (Falos) of the installation below.
Tore
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Jun , 2022, 00:02
Hello Mr. Tore and All,


Well, I'm officially 81 years old...  I don't feel that old yet, but time will tell; Ive had two (2) heart stents and it keeps on ticking...


Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 09 Jun , 2022, 11:31
Hi Don,
Happy birthday to you a few days ago and hope you had a nice day.
Best wishes,
Dougie
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 10 Jun , 2022, 03:45
Hi Dougie,
Thanks for the best wishes...  How is your book doing on Amazon? I have Skizzenbuch digitally on Amazon in the Kindle Store.
Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 10 Jun , 2022, 04:05

Belated Happy Birthday Don. 2 coronary stents mean a rejuvenated/healthy heart again!
Keep up the usual, excellent work!
SG
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 10 Jun , 2022, 10:39
Happy Birthday Don.
What kind of book is Dougie's book?
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: dougie47 on 10 Jun , 2022, 14:50
Hi Don,
The book is doing fine, thanks, with perhaps an French edition coming in due course. It is good to see your book on Amazon. I am really glad you used some of my introduction in the information part on Amazon, it has made my day.
VIC20 - My book is about U 47 and Guenther Prien and can be seen here -
https://amp.rokket.biz/books.shtml
I have also been working on an article on Type IX modifications for the last year and hoping to have it finished in the next few weeks.

Cheers,
Dougie

 
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Jun , 2022, 03:53
Hello Mr. Tore,

Patrick Salman (Discord) believes that possibly the Norwegians changed the location of the fuel pump on the GW Diesel Engines on U-995 because they do not match the GW Diesel engine drawings (See Attachment).

The images we have in Skizzenbuch shows the fuel oil pump located forward on the Diesel Engines (Skizzenbuch photo page 71 attached).

Was the location of the fuel oil pump changed by the Germans when the duel fuel filters were installed? Do you have GW Diesel engine drawings that match the changed positions...

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 06 Nov , 2022, 01:44
Hello Website Administrator,


The last email that I got from Mr. Tore stated that he could not login to his account... 


"Hello Don, nice to hear from you, I am still going strong in my 94years I am hoping to show a movie from a demo mission landsetting of underground troops in a norwegian fjord where U 995 took part. It shows some interesting external immages as well as interiors of the boat at that time, including the engineroom. It is made by the norwegian navy only a few month after I left the boat. The movie is of course in black and white but shows some original details from the 1960ties. One drawback though, where to show it ? It last approximately 5- 10 minutes. I dont know what they have done to my mailbox it seems I have been thrown out."
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 13 Nov , 2022, 02:14
Hi Don/Tore,

sorry for the belated reply. A valid option could be uploading the video on an online video platform of your choice (there are many around: https://en.wikipedia.org/wiki/List_of_online_video_platforms (https://en.wikipedia.org/wiki/List_of_online_video_platforms) ) and share the video URL here on the AMP forum. Don't know what happened to Tore's mailbox, am sure the administrators can fix the problem. Eager to see the video soon!

Cheers,

SG
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 18 Nov , 2022, 02:37
If its the same video it has been linked on here by me before.
I cant seem to link it again but a simple Google search of U995 Kaura Norwegian Navy will find a number of links to the color version.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 27 Nov , 2022, 14:39
I just got am email today...


"Yes, thank you, I've logged him back in and given him an updated link.
-Tore's Grandson Magnus."

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 29 Nov , 2022, 01:08
Hello Mr. Tore,


Do you remember or have any photos that show the device for measuring the fuel oil drained from the internal fuel oil tanks and the buckets were carried to the diesel room to measure the fuel remaining in the internal fuel oil tanks? Then the contents of the measuring device was drained into the fuel oil collection bunker/tank.

This device seems to be missing in U995.

Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Don Prince on 22 Dec , 2022, 02:00
Hello Mr. Tore and all of my very Dear Friends,


This will be my very last Christmas Card on the AMP Website for this year of 2022 to you all. I understand that the AMP Website will be shut down when we celebrate the New Year of 2023. I am so very grateful for the opportunity to have become a friend and a colleague of Mr. Tore Berg-Nielsen and all. Together, over many years of sharing knowledge with Mr. Tore Berg-Nielsen, Maciek Florek (Deceased 2nd August 2017), Simon J. Morris, and Mark Hessburg, I was able to compile their wealth of knowledge and to create the book; "Skizzenbuch: U-Boat Type VII C Project." I started this project as a novice with a steep learning curve because I only had questions and no answers. These friends and contributors were patient with me and answered all of my sometimes dumb questions; for their support I will be forever and eternally grateful. With my bitter sweet memories of long nights working with my colleagues on the AMP Website: Thank you!


Merry Christmas and Happy New Year to all, and many more years to come...

Kind Regards,
Don_
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 22 Dec , 2022, 07:06
Merry Christmas to all, too bad that the forum will close  :(
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 22 Dec , 2022, 09:26
Amen. Merry Christmas Don and all

Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: VIC20 on 01 Jan , 2023, 10:44
Happy New Year to all.
For whatever reason, the forum is still online. Someone must have forgotten to pull the plug.
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: SG on 02 Jan , 2023, 03:27
 ;D
Title: Re: Tores mailbox VIIC and VIIC/41 operation and technical details
Post by: Raymic1 on 07 Jan , 2023, 14:03
Yes Dougie can you please leave it up until at least the end of January?
I'm away on Xmas holidays and away from my laptop for 2 more weeks.
I wanted to store some reference info on my laptop before close down...thanks