ASME B31.3 Progressive Sampling
ASME B31.3 Progressive Sampling
(OP)
My understanding that progressive sampling in B31.3 work the following way:
1 Reject - 2 tracers
1 reject out of those tracer - 2 more tracers
1 reject out of those tracer - 100% NDE
what if in the first batch of sampling a welder has 4 rejects? The code does not exactly explain what to do in this situation.
1 Reject - 2 tracers
1 reject out of those tracer - 2 more tracers
1 reject out of those tracer - 100% NDE
what if in the first batch of sampling a welder has 4 rejects? The code does not exactly explain what to do in this situation.





RE: ASME B31.3 Progressive Sampling
RE: ASME B31.3 Progressive Sampling
RE: ASME B31.3 Progressive Sampling
Or you could go directly to 100%, depending on the percent of rejects to passes in the batch.
Patricia Lougheed
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RE: ASME B31.3 Progressive Sampling
RE: ASME B31.3 Progressive Sampling
RE: ASME B31.3 Progressive Sampling
As for B31.3 sample plan math: The 'batch' is the your production to date on the "Project". Any single RT reject requires a resampling of 2 additional 'tracer' RT'd welds. If EITHER of those fails, you must re-resample an additional 2 welds. If either of those second pair of 'tracers' fails, that welder's production work requires 100%.
Thus the intent of this Code is that if three samplings fail - 1st the random RT, 2nd either of the 2 tracers, 3rd either of the 2nd set of tracers - 100% RT or 100% removal of these welds [it's usually cheaper to just cut out the rest of this welders worek. RT's are expensive] So it only takes 3 rejected random RT's to engender the 100% 'death penalty'. You have 4. No further analysis required. Time to start cutting out some welds, or send a big $$$ P.O. to an RT firm.