US Divers 3-piece manifold nut size

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duckbill

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Does anyone know what the correct CGA gas fitting size is for a U.S.Divers 3-piece manifold? I bought a CGA-346 but found the nut was too small for the manifold threads.
 
CGA 540, commonly used on oxygen cylinders
 
I thought it might be, but wasn't sure. The CGA sizing is greek to me, but I knew you'd be the one who had the answer. Thankyou!
 
Just wanted to say, thanks again, Captain.

I went in today and they grabbed a set off the shelf and it fits great. Funny thing is, when I went in the first time last week and showed them the center portion of the manifold, they told me it was CGA346 and went to all lengths to scrounge the parts. I actually had to come back later when one of their repair trucks was in to get the parts. Seems I and they wasted a buch of time for nothing when the CGA540 was sitting right there in the bin! It was cheaper too, so I got a refund to boot:D
 
The Sherwood three piece manifold uses a slightly smaller fitting. I don’t know the CGA number, but it probably is the CGA-346.
I do know that the Sherwood fitting is the same as the fitting used by some of the SCBA used by firefighters.


These kinds of makes sense: The US Divers design is older and they used the O2 fitting, which was (and is) very common.
Sherwood is the largest gas/ valve company (probably in the world) and when they designed there manifold, they used an air fitting which would be more appropriate (from a valve standards point of view).
 
Actually that female nut is used for several different CGA nipples.
 
The Sherwood three piece manifold uses a slightly smaller fitting. I don’t know the CGA number, but it probably is the CGA-346.
I do know that the Sherwood fitting is the same as the fitting used by some of the SCBA used by firefighters.

This makes sense. At one point the guy mentioned SCBA and I dismissed it, not feeling it was necessary to remind him that it was for a SCUBA manifold. So, it seems, he had had some experience with SCBA units and jumped to the conclusion as to which part I needed.

I'll have to remember to check the fittings on my Healthways manifold. I may need a CGA346 nipple afterall.

Thanks.
 
I am just wondering what are you doing?
Are you making a triple manifold of some of the US Divers double manifold?
Or are you working on some other unique tank manifold configuration, like tank up-side-down with outlets on top for double hose?
 
Luis, PM sent.
 
Thanks for nothing.
 
https://www.shearwater.com/products/swift/

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