Welder Qualification Lapse on a Fracture-Critical Bridge Girder
A welder qualified in the 3G position on 3/8 in. plate using FCAW last welded production on a non-fracture-critical project 7 months ago. The shop now assigns the welder to a fracture-critical girder with 1 in. complete-joint-penetration groove welds in the 3G position using FCAW. The welder's qualification certificate shows a 6-month validity period from the date of test. The shop's records show no production welding by this welder in the interim on the qualified process. The inspector is asked to approve the assignment. Separately, the welder's test was on 3/8 in. plate, and production is 1 in.
1. Is the welder's qualification current, and what does the 7-month gap mean?
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The certificate shows a 6-month validity, and 7 months have elapsed since the last production welding on the qualified process. Under D1.5, welder qualification remains valid only if the welder has welded with the process within the specified interval; a lapse requires requalification. The 7-month gap exceeds the 6-month validity and there is no interim production welding on the process, so the welder is not currently qualified. The inspector should not approve the assignment until the welder is requalified. The lapse is independent of skill; it is a records and continuity requirement.
2. The welder tested on 3/8 in. plate; production is 1 in. Does the qualification cover 1 in.?
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Welder qualification thickness ranges are defined by the code and depend on the test thickness and position. A test on 3/8 in. plate does not automatically qualify the welder for 1 in. production; the qualified thickness range must be checked against the code's bracket for the test thickness and process. If 1 in. exceeds the qualified range, the welder must be requalified on thicker test material or the range extended per code. The inspector should verify the qualified range on the certificate and reject the assignment if 1 in. is outside it.
3. What must the shop do before this welder can weld the fracture-critical girder?
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The shop must requalify the welder for the process and position, on test material whose thickness brackets 1 in., and document the new qualification with the test date, position, process, and thickness range. Because the member is fracture-critical, the shop should also verify that the WPS used is qualified for 1 in. fracture-critical work and that preheat and interpass are specified. The inspector should confirm the new certificate, the WPS, and the procedure qualification before production, and retain copies. Only after requalification and verification should the welder be assigned.