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I am a steamfitter. If I want to test a system, lets say using 100 lbs of water and then, I want to test the same system using air, how many pounds of air would I use? In other words, what is the relationship between water and air pressure
Of course this is a practical problem, and we can't give an absolutely definite answer without knowing more about the situation. However, if some system can get pressures up to 100psi, under most circumstances all the connected pipes inside that system will reach nearly the same pressure. So if some of the water were at 100 psi, but parts of the pipes were filled with air, it would be at 100 psi too.
So I'd use the same test pressure for each.
(published on 10/22/2007)
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