Tag
#inspection
17 topics across all disciplines.
Welding processes, WPS and NDT — what happens before an arc is struck
SMAW, GTAW, GMAW and the rest, explained by what they are good at. Then the paperwork that makes a weld legal — WPS, PQR and welder qualification — and how welds are inspected.
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.
Non-destructive examination — choosing the method and reading the result
Why every NDE method is blind to something, what magnetic particle cannot do on stainless, why ultrasonics can miss a crack lying the wrong way, the difference between an indication and a defect, and why the examiner's qualification is part of the result.
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.
Material degradation — sensitisation, hardness limits and galvanic attack
Why welding can ruin the corrosion resistance of stainless steel without touching the weld, what the three conditions for galvanic corrosion are and which one to break, why sour service controls hardness rather than strength, what carbon equivalent predicts, and why zinc and stainless are kept apart.
Corrosion loops and piping circuits — the two groupings an RBI study is built on
Why a corrosion loop and a piping circuit are different things, how each one is drawn and bounded, what goes wrong when a circuit is too big or a loop mixes two streams, and why every number downstream depends on getting these right.
Risk-based inspection — deciding what to inspect, and how often
Why nobody inspects everything equally, how likelihood and consequence combine into an inspection plan, why naming the damage mechanism is the whole job, and the ways an RBI programme quietly goes wrong.
Ex installation and inspection — where compliance is actually won or lost
Certified equipment is the easy part. Glands, unused entries, flame paths, IS segregation and the inspection regime are where hazardous area compliance is genuinely decided.
Inspecting and repairing structures — the other forty years
Construction is a small part of a plant's life. What degrades, why the worst mechanisms are the hidden ones, how risk-based inspection decides where to look, and why structures quietly become overloaded.