Tores mailbox VIIC and VIIC/41 operation and technical details

[NZSnowman]

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

[SnakeDoc]

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

[tore]

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

[tore]

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.


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

[NZSnowman]

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.

[NZSnowman]

Hi Tore

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

[tore]

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

[tore]

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

[NZSnowman]

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

[tore]

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

[NZSnowman]

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?

[tore]

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

[tore]

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

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

[NZSnowman]

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.

[NZSnowman]

Fig. 1. Side view of new Air Starting supply piping.


Fig. 2. Top view of new Air Starting supply piping.


Fig. 3. New Air Starting supply piping under the decking. The layout is correct but the some of the piping and the