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Q & A: Equivalence of pressure

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Most recent answer: 07/17/2008
Q:
I can't seem to find the answer to this age old question: When pressure testing pipes, we can use either Air or Water (or other fluids). What is the equivalent pressure test, water-to-air. For example, if I am used to pressure testing with water at 120 psig, what is the equivalent Air pressure test? Can you offer your assistance?
- Dev
Barbados
A:
Pressure is pressure. It has the same value independent of the pressurizing agent.  Either a gas or a fluid will work when testing for leaks.   It might be convenient to use one or the other depending on the case.

If you have a closed pressurized system then you need some sort of gauge to measure the leakage rate. If you have a dynamic system then you need some sort of device that detects the escaping internal substance, such as a freon detector for an air conditioning system.

LeeH

(published on 07/17/2008)

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