Welding Procedure Qualification Test
Definition: The welding procedure qualification test is the qualifying proof that a defined welding procedure, under specified parameters, reproducibly achieves the required quality. The result is documented in a welding procedure qualification record (WPQR). The requirements are governed by DIN EN ISO 15614.
Practical relevance: The test comprises welding a test piece under realistic conditions as well as subsequent destructive and non-destructive testing. Typical tests are the tensile test, bend test, notched-bar impact test, hardness testing and macroscopic examination. The qualified parameters (e.g. current, heat input, material group) define the validity range of the WPS.
Decision-making perspectives:
- Technical decision-makers: Ensuring the process stability and mechanical performance of the welded joint.
- Purchasing/project management: Requiring valid WPQR documents as a prerequisite for awarding contracts.
- Science: Analysis of heat-affected zones, microstructural transformations and residual stresses.
- Insurance/law: Proof of standard-compliant procedure qualification in cases of damage.
Typical testing or verification methods: Tensile test, bend test, notched-bar impact test, hardness testing, macroscopic section examination, NDT.
FAQ:
- What is the difference between WPS and WPQR?
- The WPS describes the welding procedure, while the WPQR documents its successfully tested qualification.