WPS, PQR, and Welder Qualification
Welding Procedure Specifications, Procedure Qualification Records, Welder Performance Qualification, and CWB testing.
- Explain the purpose of WPS, PQR, and WPQ documents
- Describe the welder performance qualification process under CWB
- Identify essential variables in electrode approval and consumable lists
Leçon 1
WPS and PQR Fundamentals
Welding Procedure Specification (WPS)
A WPS (Welding Procedure Specification) is the written document that tells the welder exactly how to make a specific weld. Every CWB-certified company must have approved WPS documents for all joint types they produce.
WPS Contains
Joint design - groove angle, root gap, root face
Electrode - classification, size, storage
Amperage range - for each pass
Preheat/interpass temperature
Position - flat, horizontal, vertical, overhead
PQR Contains
Actual parameters used during qualification
Test results - bend tests, tensile tests
Visual inspection results
Welder who made the test plate
CWB engineer approval
Procedure Qualification Record (PQR)
The PQR (Procedure Qualification Record) proves that a WPS actually produces acceptable welds. A test weld is made following the WPS, then the test plate is destructively tested (bent, pulled, or broken) to verify the weld meets code requirements.
A WPS tells the welder how to make the weld. A PQR proves the WPS works through destructive testing. Both documents must be approved by CWB. A welder must always follow the approved WPS - deviating from it is a code violation.