What must a qualified pressure welder do before welding on a pressure vessel?

A qualified pressure welder must pass a welding performance test before welding on a pressure vessel to ensure they possess the necessary skills and knowledge to carry out safe and effective welding practices. This test typically evaluates the welder's ability to properly execute welding techniques according to specific codes and standards that apply to pressure vessels. Achieving a passing grade on this performance test confirms the welder's competence in producing sound welds that can withstand the operational stresses of a pressure vessel, thereby maintaining safety and integrity throughout the vessel's lifecycle.

This requirement highlights the critical importance placed on weld quality in applications involving pressure vessels, where failure can lead to catastrophic results. By ensuring that only qualified individuals who have demonstrated proficiency are allowed to perform welding tasks, the risk of defects and subsequent failures is significantly reduced, contributing to overall safety in industrial settings.