Strength of Partial Penetration Welds
Strength of Partial Penetration Welds
(OP)
The company I work for builds instrumentation for the oil & gas industry. The pressure containing parts of one of the products is built to B31.3 They are welding a 2-1/2" s/10 weld cap to S/10 pipe (316/316L). But instead of holding the root gap open and full pen. welding, they lay the cap directly on the pipe and weld. This is not a full pen weld! They don't wantto change so I am asked to determine what the strength of the gauge should be. I can determine this strength using engineering techniques of analysis but I would ask the forum what is the proper method to use. Especially since it is supposed to comply with B31.3





RE: Strength of Partial Penetration Welds
What exactly is the weld joint detail? In other words, are they simply butting the cap to the end of the pipe (with no weld root) and filling the groove that is exposed with weld metal?
RE: Strength of Partial Penetration Welds
RE: Strength of Partial Penetration Welds
1. Does the organization that is welding have a qualified welding procedure?
2. Qualified Welders?
Your first description of how the weld joint was made would be unacceptable for use in B31.1 piping applications. This is not a partial penetration weld, this is a weld that would be classified, in my mind, as inadequate penetration. Inadequate penetration is a rejectable weld defect.
RE: Strength of Partial Penetration Welds