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flange ratings and hydro testing

flange ratings and hydro testing

flange ratings and hydro testing

When hydrotesting a piping spool with say 6 inch 150 pound flanges, is there a safety factor built into the flanges and piping that would allow testing to take place above 150 pounds. If so what is the safety factor and where would I be able to reference this in an applicable code?

RE: flange ratings and hydro testing

Please look at and study the "Flange Rating Data" chart at this link.

It the upper left hand part of the chart the Box says
"Hydrostatic Test Pressure (PSIG)".  That should answer your question.

Jop (Piping Engineering & Design)

RE: flange ratings and hydro testing

Also, the pressure and temperature limits vary by flange material.  Limited relationship exists between 150 pounds (whether force or mass or pounds per square inch pressure) and the flange classes.  Review the 2009 issue of ASME B16.5 or ASME B16.34 for valves.  Perhaps Class 150 may have once had some obscure correspondence with 150 psig steam.

RE: flange ratings and hydro testing

The link doesn't work now PennPiper.


RE: flange ratings and hydro testing

see Asme B16.5 prg 2.6 for the flanges
"2.6 System Hydrostatic Testing
Flanged joints and flanged fittings may be subjected
to system hydrostatic tests at a pressure of 1.5 times the
38°C (100°F) rating rounded off to the next higher 1 bar
(25 psi) increment. Testing at any higher pressure is the responsibility of the user, taking into account the
requirements of the applicable code or regulation."

for piping you should review the applicable code

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