WELDING PROCEDURE SPECIFICATION (WPS)
The purpose of Welding Procedure Specification (WPS) and Procedure Qualification Record (PQR) is to determine that weldment proposed for construction is capable of having the required properties for its intended application. This is presupposed that welder, or welding machine operator performing the welding procedure qualification is a skilled artisan. The welding procedure qualification is therefore, strictly to establish the metllurgical compatibility of the weldment through mechanical tests and not the skill of the welder or the welding operator. In the addition to the basic property requirements, as it is expressed by engineering tension test results and bend test results, a weldment is some times prescribed for severe service conditions where the ductile to brittle transition temperature of the weldment has to be below zero degree. Procedural tests in those cases include impact tests as well, to assess the notch toughness property of the weld.