Tores mailbox VIIC and VIIC/41 operation and technical details

[NZSnowman]

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://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

[NZSnowman]

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

• The funnel is identical was the starboard side.
• The funnel is in the similar area as the starboard side.
• There seem to be a less two pipes running into this funnel.   

[NZSnowman]

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?


Fig. 1. 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.

[NZSnowman]

Fuel Drain Lines (Violet-Red-Violet) into FO Collecting Tank

• Corrected the initial fuel drain pipes layout from the Gravity Tanks.
• Added fuel drain pipes from Fuel oil venting system
• Corrected Engine Lubricating Oil piping system.

Fig. 1. Fuel Drain system.


Fig. 2. All system (Lots of pipes and vlaves )

[tore]

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

[tore]

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

[tore]

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

[NZSnowman]

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.

[NZSnowman]

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.


U-Boote Crews: 1939 - 1945 by Jean Delize

[tore]

simon.
I guess this is the thing.
Tore

[SnakeDoc]

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

[NZSnowman]

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

Thanks Maciek!

I am starting to think that they used them a lot, this would make sense.

[NZSnowman]

'T' handles hatches within the floor plating

[tore]

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

[tore]

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