RE: [PSUBS-MAILIST] o-ring hull penetrations

[VBra676539@aol.com]

Alec,

I got it that time. I agree with Phil that, for starters, SS is probably the best thing to use. As to the design, you will need a couple of nylon or delrin thrust washers down on the inner flange to avoid the arthritis problem exacted by increasing external pressure.

You might consider scrapping the well idea and have an outer flange on your reach rod with, if you really want to be fussy, an o-ring on a bushing or something and a nut/washer on the inside to retain the rod.

In your B drawing, just weld it on the outer flange, but, as Phile suggested, if you build the slug in 316 to start with then the whole thing is moot. There used to be a bunch of fussing about stress corrosion in the welds from SS to mild steel. Phil says no, and I don't know any better, so who better to agree with? I know his DWs have mating rings welded just that way. Sounds good to me, main!

Vance