Hydrostatic/pressure/leak test for ASME B:31.3, 31.4, 31.8

[engr2GW]

Hi,
In B31.3, the pressure test is usually 1.5xDP
B31.4 says 1.25xDP and
31.8: 1.25 to 1.5xMOP depending on class and division of location
Question: is this test pressure and media for both welded, threaded, etc joints of pipes and/or fittings or for only welded?

Thank you.

 

[moltenmetal]

For B31.3, it's for any means of attachment, unless the pipe is in Category D (non hazardous) service in which case the owner can opt to test the piping in service only.

For the other codes- sorry, don't know- never read 'em.

 

[moltenmetal]

For B31.3, it's for any means of attachment, unless the pipe is in Category D (non hazardous) service in which case the owner can opt to test the piping in service only.

For the other codes- sorry, don't know- never read 'em.

 

[ENGMechanical]

Conform I read ever, I understand that is not for welded. For a Hydrostatic pressure test I ever consult the nameplate on vessel, or with designer of vessel the H.T condictions before. For pipe, is recomended use 1.5 x DP. Or use formula:

Pt=1.5PSt/S

where:

Pt=Minimum test gage pressure
St=Allowable stress at test temperature
S=Allowable stress at design temperature
P=Design gage pressure

Best regards
Edilson