Minimum weld requirement

[inspjac]

What is the minimum pass that should be made in a groove joint before a joint is temporarily stopped eg. root and hot pass or like 30% or 40% of the pipe thickness. To avoid cracking etc....What is the right answer for this?

 

[stanweld]

Depends on the material (carbon equivalent for steels), joint restraint, preheating requirements, etc. Be more specific in your question.

 

[inspjac]

Dear Stan
My question was if a welder wants to stop the weld, what should be or up to minimum the welder should complete the joint, before leaving. Suppose if multi-process weld joint, a welder should do the 1. GTAW-rootpass, hotpass and SMAW-one pass. or 2.GTAW-rootpass, hotpass only.

thanks
jacob

 

[stanweld]

Welds can be stopped at tacks with no cracking in low carbon and non hardenable alloy steels. With the GTAW process, welds can be discontinued during the root pass without cracking depending on carbon equivalent, joint restraint, preheat. If you need a Code to guide you, refer to ASME B31.1, section 131.6.