The term 6G refers to the position and type of joint used in the welding certification test. The number 6 refers to the 45-degree angle that cannot be moved by the individual taking the certification test. G refers to the grove weld that must be used during the test.
To prepare candidates for the ASME 6G welding certification test Alaska's Institute of Technology teaches subjects including the use of oxyacetylene cutting equipment to prepare the pipe for welding. To pass the 6G certification test individuals must be able to prepare, tack weld and weld pipes in the 6G position.
Candidates for the 6G welding certification are experienced welders who have obtained previous certification, such as the American Welding Society D1.1 structural steel code certification.