When qualifying a welder on GMAW-S under the requirements of ASME Section IX, which statement is true?

In the context of qualifying a welder under GMAW-S (Gas Metal Arc Welding – Short Circuit Transfer) according to ASME Section IX, the correct statement is that the welder may qualify by mechanical testing of a test coupon. This aligns with the requirements outlined in ASME Section IX, which stipulates that welders demonstrate their ability to produce sound welds meeting specified criteria through actual weld tests.

Mechanical testing typically includes procedures such as tensile tests and bend tests on the welds made during the qualification process. This is critical because it validates not only the welder's skill but also the integrity and performance characteristics of the weld metal. Through mechanical testing, one can assess fundamental properties, such as strength and ductility, ensuring that welds are not only visually acceptable but also meet functional requirements for service.

A qualification based only on visual inspection would not provide the necessary evidence of weld integrity and might overlook defects not visible to the eye. While specific electrode sizes or oral examinations may be part of the training process or qualifications for certain scenarios, they are not universally required under the provisions for qualification as set out by ASME Section IX for GMAW-S. Ultimately, mechanical testing is essential for confirming that the welder is capable of creating