Tores mailbox VIIC and VIIC/41 operation and technical details

[NZSnowman]

Tore, any idea what the grease distribution boxes would look like? Or how it may work?

[NZSnowman]

Tore, I have added the two new linkages, and updated the muffler


Fig. 1. New drawing


Fig. 2. Old drawing.

[tore]

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.  
Tore

[tore]

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

[tore]

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

[NZSnowman]

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.


Fig. 1. The 2nd newer grease line.

[NZSnowman]

Tore, I have added the two new linkages, and updated the muffler


Fig. 1. New drawing


Fig. 2. Old drawing.

Top view

[tore]

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

[NZSnowman]

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!

[NZSnowman]

Grease Distributor and Lines

[tore]

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

[NZSnowman]

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

[tore]

Simon.
Just as good, I based my assumption on the cheapest way of production.
Tore

[tore]

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

[NZSnowman]

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.

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