UPVC pipe design 1

[guanghui an]

when we design UPVC piping, do we need to select the pipe wall thickness as per hydrotest pressure? because after installation, we need have a hydrotest for piping, the hydrotest pressure is 1.5xdesign pressure.

 

[LittleInch]

Generally , no, you determine wall thickness as per the design requirements. Most designs allow for the extra stress in the hydrotest case. E.g if you need say 10 bar, then but pipe rated for 10 bar. The fact you test it at 12.5 or 15 is included in the design, i.e. you don't buy 15 bar pipe if 15 is the hydrotest pressure.

UPVC might be only 1.25 times rated working pressure / design pressure. You would need to check manufacturers specifications / data sheets.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[moltenmetal]

Be very careful. Selecting the MAWP of pipe itself is comparatively easy. However, the MAWP of a PVC piping system will depend on the MAWP of the lowest rated component. That will usually NOT be the pipe, but rather the flanges and unions which are only 150 psig/10 bar rated at room temperature. Threaded and cut grooving connections also reduce MAWP.

 

[guanghui an]

thanks for Littleinch and Moltenmetal