[PSUBS-MAILIST] Double Seal?

[James Frankland]

Hi All,

I have to re-machine the pop off top of my overpressure valve.  I threaded the hole by hand and now i have finally attepted to fit it with its O ring, i can see that the bolt is not straight, causing mis-seating of the valve top.   Im not over happy with having the bolt passing through anyway as it doesnt slide very easily.

So, im going to machine up a new smooth shaft which should be straight.  Thats easy enough.

BUT, at the same time, i am tempted to put in a second O ring groove and have 2 O rings on the pop off top.  There is enough room for one outside the existing.

I seem to remember there was discussion on double O rings a while ago.  Anyone have any thoughts on this idea?  Seems to me to be a good idea as its got 2 seals, but ?

Pic here as i was machining it.

Kind Regards
James

http:/<http://www.guernseysubmarine.com/publication2_files/Page20544.htm>/www.guernseysubmarine.com/publication2_files/Page20544.htm
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