A WPS is a written document that provides direction to the welder for making production welds. It outlines the specific parameters—such as current, voltage, travel speed, joint design, and post-weld heat treatment (PWHT). The WPS is essentially the "recipe" for the weld.
Welding is a critical fabrication process used in the construction of pressure-containing equipment, piping systems, and structural components. Due to the potential catastrophic consequences of failure, the American Society of Mechanical Engineers (ASME) has established rigorous codes to govern welding quality. This paper provides an overview of the ASME welding certification ecosystem, distinguishing between the certification of organizations (Quality Management Systems) and the qualification of procedures and personnel. It focuses primarily on the requirements of ASME Section IX , while contextualizing its application within the Boiler and Pressure Vessel Code (BPVC) and B31 Piping Codes. The paper outlines the methodology for developing Welding Procedure Specifications (WPS), qualifying Procedure Qualification Records (PQR), and certifying Welders/Welding Operators (WPQ/WQ), emphasizing the importance of Essential Variables in maintaining weld integrity. asme certification welding