IIW IWI-C case studies
IIW IWI-C · Put your knowledge to work in context.
The International Welding Inspector Comprehensive (IWI-C) is the highest of the three IIW inspector qualifications, sitting above the Standard and Basic levels. It is aimed at engineers and senior inspection staff who already understand welding processes and want responsibility for procedure qualification, inspection planning, defect acceptance decisions and the contractual side of welded fabrication. The IIW IWI-C case studies are 5 cases and about 3,135 words.
1Duplex 2205 spool: interpass失控 and low toughness
A fabrication shop is producing 12.7 mm wall 2205 duplex stainless steel spools to EN 10216-5. The WPS specifies GTAW root with ER2209 and FCAW fill with E2209T1-4, no preheat, maximum interpass 150 °C.
561 words, about 3 min2Fatigue crack at an eccentric diaphragm-to-web fillet
A 20-year-old road bridge has a 12 mm thick diaphragm plate fillet-welded to the web of a 1500 mm deep plate girder. The connection was designed as a non-load-bearing detail, but a recent inspection found a 35 mm long toe crack at the diaphragm-to-web weld, starting at the weld toe on the web side.
664 words, about 3 min3Thick-section PQR extension for a pressure vessel seam
A pressure vessel shop is welding a 38 mm thick SA-516 Gr.70 shell in the longitudinal seam. The existing PQR to ISO 15614-1 was made on a 12 mm thick test piece using GTAW root (ER70S-3) and SMAW fill (E7018), single-V, with a steel backing strip, welded in the flat position (PA).
650 words, about 3 min4Planar UT indication in a thick nozzle-to-shell weld
A 60 mm thick low-alloy steel nozzle-to-shell weld (set-on, full penetration) is examined by manual pulse-echo UT after PWHT. The scan uses 45° and 60° shear-wave probes, 2 MHz, and a DAC curve from a 3 mm side-drilled hole.
625 words, about 3 min5Subcontracted EXC3 fabrication without welding coordination
A steelwork contractor is awarded a contract for a two-storey steel frame to EN 1090-2, execution class EXC3. The contractor holds EN 1090-1 FPC certification and has a welding coordinator (IWE).
635 words, about 3 min