Tag
#qaqc
10 topics across all disciplines.
Reading a WPS and a PQR — what is on the sheet and what the tests proved
The practical document skill — what each field on a welding procedure specification is for, what a qualification record actually recorded, and what tensile, bend, impact, macro and hardness results each demonstrate about the joint.
Section IX essential variables — what invalidates a procedure qualification
Why a WPS can be revised freely in some respects and requalified from scratch in others. Essential, non-essential and supplementary essential variables, the ranges a PQR actually qualifies, and the low-temperature trap that turns a harmless change into a requalification.
Welder qualification and continuity — the ranges a ticket covers, and the register nobody updates
What a welder performance qualification actually establishes, the ranges it carries in thickness, diameter, position and process, how continuity lapses at six months, and why the expired ticket is always found after the weld is made.
Joint preparation and fit-up — the hold point you only get once
Bevels and root gaps, internal misalignment and the limits on it, why trimming or counterboring is allowed where grinding the bore is not, tack welds as part of the final weld, and what an inspector checks in the minutes before the root goes in.
Preheat and post-weld heat treatment — hydrogen, hardness, and reading the chart
What preheat is actually for, why interpass temperature has a ceiling as well as a floor, when PWHT is required and when it may be exempted, how to read a chart recorder trace against the specified cycle, and the hardness survey that decides it in sour service.
Examination extent and progressive sampling — what five per cent actually obliges
How fluid service sets the amount of examination, why the sample has to represent each welder on each procedure, and the progressive sampling rule that turns one rejected weld into a widening scope — the part of Chapter VI taught almost nowhere.
Inspection and test plans — hold, witness, review, and who signs
What an ITP actually is, how it is built line by line from the code and the specification, what each of the four intervention levels obliges, why a document full of hold points is worse than a short one, and the notification failure that turns a witness point into nothing.
Non-conformance and corrective action — the four dispositions, and why NCRs repeat
Writing an NCR somebody can act on, the difference between rework, repair, use-as-is and reject, who may grant a concession, and why closing non-conformances one at a time without ever raising a corrective action guarantees the same defect next week.
Inspector competence and certification — who may interpret, and who only operates
SNT-TC-1A as an employer's written practice rather than a certificate, ISO 9712 as the independent route, what Levels I, II and III may each do, and why the inspector's own qualification is the first thing a client audits.
Pressure test packs and reinstatement — the gate, and what gets put back afterwards
What a test pack contains and why it is built as the work proceeds, the procedure and the calibrated gauge, the falling pressure that is temperature rather than a leak, and the reinstatement register that is what actually keeps a tested system honest.