VIIC/41 - Schematices drawing

[NZSnowman]

Low pressure air line

I had been rechecking the piping for the low pressure air line. That do you think about this:

Pneumatic tools connection


Red Arrow = Pressure gage (missing).
Blue Arrow = Connection points.
Yellow Arrow = Valve c.

I think they may have updated the low pressure system for the Type VIIC/41. Here a suggestion for the new low pressure air line.

Red arrow = Flow of low pressure air.
Blue arrow = New master valve.
Yellow arrow = Low pressure line to tube II & IV (Port Side), control by new valve (pink arrow).
Green arrow =  Low pressure line to tube I & III (starboard side), control by new valve (megente arrow).
Black arrow = Pressure hull valve for forward buoyancy tank.

What do you think

[Rokket]

I'm not knowledgeable enough to comment on anything but the tool connection - it's similar in Gatos, so I can sort of recognise that!

[NZSnowman]

Hi gents,

Great photos! Some of these photos are from "Die deutschen U-boote und ihre Werften" by E Roessler. They show U 235 in October 1943.

U 235 was very unusual in several respects. Firstly when it was commissioned in Dec 42 it had an original tower but with the late styl;e of deck (planked). A quite unusual combination!

By October 1943 it had a snorchel and a Turm II. This Turm II was a little different than normal - there has a curved edge to the tower that can be clearly seen in the last photo.

Cheers,

Dougie

Hi Dougie

I was thinking about U-234, perhaps she was unusual because she was a training and school U-boat, and they keep she update with each new equipment to train the sailor on

She was also unusual at her dead! So near the end of the war (14 April 1945), she was sunk in error by a depth charges from the German torpedo boat (all hands lost)   I wonder if this was the only U-boat the Kriegsmarine sunk.

[NZSnowman]

I'm not knowledgeable enough to comment on anything but the tool connection - it's similar in Gatos, so I can sort of recognise that!

I am not knowledgeable enough either. I am still learning!!

That is one thing I like, that each day I learn something new

[NZSnowman]

Impulse Tank/High pressure air bottle for torpedo tube

[SnakeDoc]

Hi Simon

Were you able to locate the pressure gage before valve c₂?

Well, I think that it is located at top, port torpedo tube:



with the probe line leading from the valve as marked here:



The similar arrangement here:



--
Regards
Maciek

[SnakeDoc]

Low pressure air line

I had been rechecking the piping for the low pressure air line. That do you think about this:

Pneumatic tools connection


Red Arrow = Pressure gage (missing).
Blue Arrow = Connection points.
Yellow Arrow = Valve c.

I think that there are two possibilities:
1. Connection points you have marked with blue arrow are for pneumatic tools, and they are connected to line
visible near the frame, which is led from the port side and from the bulkhead.
2. Connection points are for torpedo testing and charging and are connected to the HP air system.

I can not find any photos clear enough to determine this.

I think they may have updated the low pressure system for the Type VIIC/41. Here a suggestion for the new low pressure air line.

Red arrow = Flow of low pressure air.
Blue arrow = New master valve.
Yellow arrow = Low pressure line to tube II & IV (Port Side), control by new valve (pink arrow).
Green arrow =  Low pressure line to tube I & III (starboard side), control by new valve (megente arrow).
Black arrow = Pressure hull valve for forward buoyancy tank.

Well, I had thought initially, that valves you marked belongs to torpedo high pressure air manifold with:
Red and Green arrows - outputs respectively to the
charging air impulse tanks and torpedoes and to the air motor for anchor capstan.
Yellow arrow with opposite direction would be input from Control Room,
and that one marked as inflow would be drain to the bilge.

The valves for controling low pressure air lines would be gathered at the port side of bulkhead...

--
Regards
Maciek

[SnakeDoc]

I have tried to back trace the connection to torpedo HP air manifold by locating connections
for charging torpedo impulse tanks:





green arrows - valves c₁
black arrrow - frame No 75
red arrows - HP charging lines

The lines are connected by the bridge line which is led near the frame No 75.
But I cannot determine, how where the joints are located exactly, and how it goes
backward to the bulkhead.


--
Regards
Maciek

[NZSnowman]

Hi Simon

Were you able to locate the pressure gage before valve c₂?

Well, I think that it is located at top, port torpedo tube:



with the probe line leading from the valve as marked here:



The similar arrangement here:



--
Regards
Maciek

Hi Maciek

I am not sure if we are talking about the same pressure gage, as I was thinking there was only one pressure gage to measurement the pressure in Bank 6 (being located before it spit to port and starboard)?


Plate 11:  High pressure air system


Plate 25:  Torpedo tube firing, venting, flooding and drainage systems

[SnakeDoc]

Hi Simon

I am not sure if we are talking about the same pressure gage, as I was thinking there was only one pressure gage to measurement the pressure in Bank 6 (being located before it spit to port and starboard)?

Yes, we talk about the same :-)
The last picture is an example of arrangement - thick, probe line connecting valve with gauge.
It was not related with the one, you asked for.

--
Regards
Maciek

[NZSnowman]

While drawing the Impulse Tanks, I notice two small outlets near the top of the bottle. The left outlet look like a line to a pressure gage and the right look like a safely valve You can see both in P1100414.JPG. Do you know anything about them

Thanks for the answer below

Still looking through all the new data you posted today, but several things do make more sense about the high pressure system on the starboard side. It would be very

[SnakeDoc]

Hi Simon

I must say there so much new data and things, that I am starting to lose track on all the piping I will need to read all our posts again to fully understand it before I start adding each subsystem to my drawing.

Well, I'm sure that you can easly figure out all that mess - after you managed out to draw Diesel Engine Room you are
one of the most qualified and experienced person to do that task.

--
Regards
Maciek

[SnakeDoc]

Finally I have found a mysterious piece of installation:







On the first image I have marked with:
red arrow - valve, which seems like either valve without second/output line or hull valve.
green arrow - part, which looks like pressure regulator
blue arrow - valve - maybe to set desired pressure on regulator

I was also not able to trace the pipe, which is going downward to the blue valve.

On photos there are visible one pressure gauge and one probe line and place, where second pressure gauge was mounted.
The existing pressure gauge is scaled up to 25 at, so it seems like it is located at low pressure side.
Was the missing pressure gauge located at high pressure side?

The most probably function of this installation would be pressure reduction on line, which is connected to air
motor for anchor capstan.

The other possibility is that it is late-war or even post-war modification. I have found this picture of Forward Torpedo
Room of type VIIC boat and compared it with the view of U-995.





The photo is not clear and detailed but I can not see these valves.

--
Regards
Maciek

[NZSnowman]

On this day, 3 years ago I started my drawing and I still have 3-4 years to go.

[SnakeDoc]

Hello

One interesting thing I have noticed lately.

As we know, on type VII U-Boats, the anchor capstan was driven by the compressed-air propelled motor,
which was located in the Forward Torpedo Room, in the bilge, between the torpedo tubes.


(source: http://www.uboatarchive.net)

On the photo of Forward Torpedo Room on U-570, there are visible one driving shaft connecting motor with driving gear,
and one shaft, which connected the upper deck with control valve, located in the bilge, near the motor.

Till now, I have always thought, that on the U-995 was similar - they only removed the shafts, to make visiting easier.
On the following photo, I marked the part, which I thought was a drive gear.


(source: U-995 DVD http://www.uboataces.com/u995.shtml)

But during my researches, I think, that someone - either German, or Norwegians, moved the motor up to the ceiling -
and made it similar as on type IX boats.


Forward Torpedo Room of U-190 (source: "Vom Original zum Modell: Uboottyp IX C")


Forward Torpedo Room of U-505 (source: http://www.uboatarchive.net)


This modification required the change in HP air lines - that's what I have noticed:

On the following picture, I have marked the input line and regulating valve.



Here I've marked line connecting regulating valve and air motor.



Another view:





May the motor was moved by Germans, to make the easier access to the LUT setting device?


--
Regards
Maciek