Who knows how much psi copper can take?

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MisterSteve124
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Tue Feb 06, 2007 7:23 pm

Does anyone know how much pressure copper pipe can take? Either 1/2 or 3/4 inch is what I plan on using. I am looking for it to hold up to 100psi which I imagine it could easily but I'm just checking. Thanks
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jjk92
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Tue Feb 06, 2007 7:37 pm

i dont know but i found this handy little guide remember that P= allowable pressure, psi
S = maximum allowable stress in tension, psi
tmin = wall thickness (min.), in.
Dmax = outside diameter (max.), in.
C = a constant
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MisterSteve124
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Tue Feb 06, 2007 7:39 pm

Yeah how the hell am i supposed to know the allowable stress in tension of copper? Does anyone wanna just tell me instead of giving me a math problem?
Hawkeye
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Tue Feb 06, 2007 7:42 pm

Copper comes in different thicknesses too. Even the thin walled stuff will hold at least 300 psi safely. Copper is great if you want a more realistic looking gun.
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Hotwired
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Tue Feb 06, 2007 8:13 pm

The thinner the copper tubing the higher its pressure rating

I mean look at this stuff: http://www.airlines-pneumatics.co.uk/we ... de=S080023

That burst pressure is in BARS.

100psi is nothing for domestic copper piping. I'd feel safe with 300psi with all metal fittings attached to it.
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MisterSteve124
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Tue Feb 06, 2007 8:21 pm

Ok thanks but its not the thinner the pipe the higher pressure rating its the smaller diameter pipe the higher the pressure rating which pretty much goes for all pipes.
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boilingleadbath
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Tue Feb 06, 2007 8:23 pm

Some relevent links:

<a href="http://www.copper.org/applications/plum ... .htm">K</a>
<a href="http://www.copper.org/applications/plum ... .htm">L</a>
<a href="http://www.copper.org/applications/plum ... .htm">M</a>

You'll be using drawn tubing... I don't know which wall thickness (K/L/M) you'll be using, though.
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Hotwired
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Tue Feb 06, 2007 8:39 pm

Ok this site is godly: http://www.indanc.com/tubing_62.php

In other words you need a scuba tank to blow out a copper tube.
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mark.f
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Wed Feb 07, 2007 6:48 am

Mainly it's your fitting choice that will dictate your operating pressure. If you use wrought and soldered fittings, you'd be good around and under 500 PSI, assuming your tubing is rated to that, (mine said). If you use compression nuts, your working pressure will be a little lower. Most compression fittings you get off the market that aren't made for very high pressure applications, and their rated to 150 for 5/8" OD tubing, (1/2" copper), and there's no rating for 7/8" OD tubing, (3/4" copper). Self-aligning compression fittings get higher ratings, with 650 PSI for 5/8" OD copper, and about 400 PSI for 7/8" OD. Problem is, you'll have a hard time finding 7/8" self-aligning fittings...
Hawkeye
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Wed Feb 07, 2007 8:42 am

Don't forget Just-For- Copper glue as well. It will hold 500 psi.
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85Dave
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Wed Feb 07, 2007 11:44 am

copper may not be too good...its too pricey at this time at least in my area

plumbers are going PVC now

but if ya got that type money go for it


you could try Rigid piping from the electrical department in lowes or home depot or even EMT pipe but be aware of EMTs thin wall...
its not made for pressure
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BC Pneumatics
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Wed Feb 07, 2007 6:25 pm

'How many psi'
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Hotwired
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Wed Feb 07, 2007 8:09 pm

In short: ~400psi working pressure is as low as it gets and thats for 54mm. As the size decreases the rating goes up and up and up...
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chaos
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Thu Feb 08, 2007 5:35 am

http://www.swagelok.com/downloads/webca ... 01-107.PDF

good page on pressure ratings

peace
Chaos
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