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Name: Michael N.
Status: Educator
Age: 40s
Location: N/A
Country: N/A
Date: March 2004

Is there a difference in the psi rating of a pipe for air as opposed to a liquid? ie. Will a pipe rated for 60 psi perform equally for air and water?

The 60 psi pressure rating is good for any fluid. The fluid may be water or compressed air. Please remember pressure is pressure, no matter what is exerting that pressure. I hope that this helps.


Bob Trach


My first response is to say that there is NO difference. Pressure is pressure. I can tell you that water is for the most very INCOMPRESSIBLE. While air is VERY COMPRESSIBLE. Of course, this is all going under the assumption that the liquid is a chemical that can be contained in the pipe or tubing. But to answer your question, I do not think there is a difference.

Darin Wagner

Air or water should not make any difference with respect to pressure. Other factors such as corrosion resistance may be different however, which could ultimately affect the pressure rating.

Vince Calder

There is no difference in the rating for air or liquid when it comes to pipes. Pressure is pressure, whether it is liquid or water, so a pipe rated for 60 psi will perform equally for water or air.

Christopher Murphy, P.E.

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