Canada BWR case studies
Canada BWR · Put your knowledge to work in context.
The Canada BWR credential is a welding certification exam built around the Canadian boiler and pressure vessel regulatory framework, with content aligned to ASME Boiler and Pressure Vessel Code Section IX practice as it is applied in Canada. It is aimed at welding inspectors, welding coordinators, quality control personnel, and experienced welders or supervisors who need to demonstrate that they understand how welding is qualified, documented, and controlled on pressure-retaining work. The Canada BWR case studies are 5 cases and about 2,039 words.
1Root Pass Porosity After Shielding Gas Change
A contractor is welding 12.7 mm thick ASTM A516 Gr.70 plate with the GMAW spray-transfer process using ER70S-6 filler at 1.2 mm diameter. The WPS specifies 75% Ar/25% CO2 at 15 L/min, 26 V, 240 A, and a 3 mm root gap.
455 words, about 2 min2PQR Impact Toughness Failure at -30 C
A fabricator qualifies a GMAW-P procedure on 25 mm ASTM A572 Gr.50 plate using ER70S-6 filler and a 75% Ar/25% CO2 blend. The PQR shows tensile tests passing and a 180-degree bend passing, but Charpy V-notch testing at -30 C returns 20 J, 22 J, and 19 J average 20 J.
440 words, about 2 min3Welder Performance Test on a Different Joint
A welder holds a performance qualification for GMAW spray transfer on 10 mm plate in the flat position with a single-V butt joint and backing. The company now needs him to weld a 6 mm thick, single-sided, open-root butt joint in the vertical-up position without backing on a pressure-retaining component.
410 words, about 2 min4Filler Metal Mismatch on a Low-Alloy Pressure Vessel
A shop is fabricating a pressure vessel from 19 mm ASTM A387 Gr.11 Class 2 chrome-moly plate. The WPS calls for GTAW root and SMAW fill using an ER80S-B2 root and E8018-B2 covered electrodes, with preheat of 200 C and post-weld heat treatment at 690 C.
356 words, about 2 min5Hydrogen Cracking After Rapid Cooling
A field crew is welding a repair on a 32 mm thick A516 Gr.70 nozzle using SMAW with E7018 electrodes. The WPS requires 100 C preheat and a maximum interpass of 250 C.
378 words, about 2 min