Welder Qualification Test — What It Is and Why It Matters
A welder qualification test (also called a welder performance qualification or WPQ) is a practical test that demonstrates a welder's ability to produce sound welds using a specific process, filler metal, and position per a qualified WPS. Passing the test qualifies the welder to perform production welding within the essential variable limits of the test.
The test typically involves welding a coupon (plate or pipe) in the specified position, which is then inspected visually and tested — either by destructive methods (guided bend tests) or radiographic examination. The specific test requirements are defined by the governing code (AWS D1.1, ASME Section IX, API 1104).
Qualification is not permanent — most codes require re-qualification if the welder has not used the qualified process for a specified period (typically 6 months). Some employers require periodic re-testing regardless. A welder's qualification record documents the specific processes, positions, and material ranges the welder is qualified to perform.
Frequently Asked Questions
Does a 3G qualification cover 1G and 2G?
Under most codes, yes. A 3G plate qualification qualifies the welder for 1G (flat), 2G (horizontal), and 3G (vertical) positions on plate. A 4G qualification covers 4G and 1G. A 6G pipe qualification covers all positions on both plate and pipe — making it the most comprehensive single test.
How long does a welder qualification last?
Under AWS D1.1, qualification remains valid as long as the welder continues to use the qualified process without a gap exceeding 6 months. Under ASME Section IX, the qualification can expire if the welder does not use the process within the code-specified continuity period. Employers may impose additional re-testing requirements beyond code minimums.