Performance Qualification of Welders
Performance Qualification of Welders
Performance qualification (also called welder qualification) tests a welder's ability to produce sound welds using a qualified WPS. In Canada, CSA W47.1 and CSA W59.2 outline requirements for welder qualification. A welder is qualified for specific variables: process, position, joint type, base metal thickness, and filler metal. The qualification test typically involves welding a test coupon that is then subjected to visual inspection and destructive testing (e.g., bend tests, macro etch). The welder's qualification must be renewed periodically (e.g., every 6 months in some jurisdictions) or when there is a change in essential variables. A welder who has not welded with a process for a certain period (e.g., 6 months) may need requalification.
A common trap is confusing welder qualification with procedure qualification. Welder qualification tests the individual's skill, while procedure qualification tests the welding procedure. Another trap is assuming that a welder qualified in one position (e.g., flat) is qualified in all positions; position is an essential variable for performance qualification. Also, a welder who changes employers may need to requalify unless the qualification is transferable and current.
Worked example: A welder is qualified per CSA W47.1 in the flat position (1G) using SMAW on 10 mm plate. A new job requires welding in the vertical-up position (3G) on 12 mm plate. The welder is not qualified for vertical-up or for 12 mm thickness (if the qualification thickness range is limited). Therefore, the welder must be requalified for the new position and thickness.
Rule of thumb: Welder qualification is specific to process, position, thickness, and filler metal. Always check the welder's qualification record against the production requirements.