A pressure-retaining weld failed twice in service. Two prior investigations blamed welder technique; a third blamed the filler metal. Neither remedy stopped the recurrence.
Metallographic examination of the actual failed section rather than a representative coupon
Hardness traverse across the heat-affected zone revealing a hardness spike inconsistent with the stated PWHT
Review of the PWHT chart records against the WPS — the thermocouple placement did not represent the thickest section
Root cause established as incomplete post-weld heat treatment, not technique or consumable
Revised WPS and PWHT thermocouple placement, plus a witness requirement on the first three production welds
A 7-storey 1970s office block had to stay occupied through a seismic retrofit. The original drawings were incomplete, concrete strength varied by 40% between cores, and the client could not vacate more than one floor at a time.
A die-cast aluminium pump housing was 22% over its mass target but the tool was already cut. A new tool would have cost the programme five months.
A 42 MWp plant's provisional connection offer carried a reactive capability condition the originally specified inverters could not meet across the full voltage range. The issue surfaced three weeks before financial close.
