What information is typically included in a Welding Procedure Specification?

• A. Process, filler metal only
• B. Preheat and interpass temperatures only
• C. Process, filler metal, preheat and interpass temperatures, welding positions, joint design, and acceptance criteria; essential and nonessential variables
• D. Acceptance criteria only

Answer: (C)

A Welding Procedure Specification is the formal recipe used to produce consistent, code-compliant welds on a project. It includes the welding process to be used, the filler metal specification, and the required temperatures such as preheat and interpass temperatures, because these factors determine heat input, chemistry, and weld quality. It also specifies how the weld should be made in terms of welding positions and joint design, since position and geometry affect accessibility, heat distribution, and weld performance. The document sets the acceptance criteria so inspectors know what quality and workmanship are required, and it lists essential and nonessential variables that can influence the weld outcome. All of these elements together give a complete guide for producing and evaluating the welds.