Max pressure for 2" steel chamber and PSV valve?

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Alex345
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Thu Aug 13, 2015 7:43 pm

So I've gotten my shiny new air chamber for the B*tch! I remember once seeing a chart from someone who had tested common sizes of galvanized steel pipe until catastrophic failure occurred. It's been a while but it came down to the fact that the smaller pipe sizes could hold the most pressure.

My chamber is a 50cm long piece of 2" galvanized steel pipe, this is sanitary pipe and (unfortunately) not for gas. And my PSV valve has no pressure rating written on it but it looks very heavy duty, but since I'll still have to hold this thing close to my face I'd at least like some kind of guideline on how much pressure she can handle :D

Currently i'm thinking around 25 bar will be safe, but if the valve can handle over 100 bar i might replace the sanitary pipe chamber with the same length of gas pipe (thicker walls) and aim for 55 bar (+-800psi)
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Gippeto
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Fri Aug 14, 2015 2:17 pm

http://www.engineeringtoolbox.com/wroug ... _1123.html

Make SURE that you GET what you THINK you're buying. Rated pipe will be marked AS such. Also note that ratings exist for a reason....if you choose to exceed them, you do so at your own peril.

Curious why you think the valve can handle 100bar/1450psi as well. :| If you check the manufacturers website, they should have a pressure rating published. I very much doubt that it's rated for much more than 150psi...

As you say...it's close to YOUR face....


Also...PSV valve?? Is that the manufacturer? PSV's are Pressure Safety Valves where I come from.....
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Alex345
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Fri Aug 14, 2015 3:16 pm

That's why i wanted to ask you guy's first :)

This is sanitary (plumbing) pipe, i've seen that chart before but i've never heard of wrought steel tube, wrought iron yes, like for gate/fence decoration. As far as i know this pipe is sold as galvanized welded steel water pipe.

It's about 4mm thick so it should be sch 40 pipe. I just assumed the valve could take higher pressures just because it's built like a tank but yeah maybe I'm being a bit too enthusiastic... I actually posted a thread about it right after i picked it up for cheap about 2years ago, i think you replied to that thread as well Gippeto? Been a while. Nobody really knew what it was, but most put their money on a PSV valve so i ran with that.

http://www.spudfiles.com/materials-ammo/topic24961.html

DIY stores don't sell pressure rated steel pipe here, mine only has a logo stamped into it but that's all. A diamond shaped symbol with what looks like an S in the middle?
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