It is clear that the fabrication of welds free from defects or, more realistically, with a quality level which is in accordance with the specifications to be applied, is closely related to the use of an appropriate procedure in terms of joint features and welding techniques. Otherwise, it is highly likely that welds are affected by serious imperfections or that joint properties do not comply with the service conditions; this leads to non-compliant welding.
Consequently, it is necessary to carry out a set of activities to validate the welding procedures and to ensure that the operating staff has the necessary expertise to put into effect what has been designed.
The Welding Qualification Procedure consists of the identification of the essential variable values that allow to get a sound welded joint, which has metallurgical characteristics suitable for use and the desired mechanical, corrosion, good appearance properties.
In essence, the welding procedure certification is a verification that the base material, the filler material and the welding technique used to manufacture the joint are able to realize what the project provides. After testing of the specimen, a Welding Procedure Qualification Record (WPQR) or Procedure Qualification Record (PQR) will be issued, which aims to record the testing results and the range of qualification, i.e. the range of the essential variable values qualified on the basis of the performed procedure test.
In collaboration with the most prestigious accredited certification bodies, Metalprove S.r.l. issues welding procedures according to:
- EN ISO 15613 about pre-production welding test for metallic materials;
- EN ISO 15614-1 about arc and gas welding test for steels and nickel alloys;
- EN ISO 15614-2 about arc welding test for aluminum alloys;
- EN ISO 15614-5 about arc welding test for titanium, zirconium and their alloys;
- EN ISO 15614-6 about arc welding test for copper and copper alloys;
- EN ISO 15614-7 about overlay welding test for metallic materials;
- EN ISO 15614-8 about welding test of tubes to tube-plate joints for metallic materials;
- EN ISO 15614-11 about electron and laser beam welding test for metallic materials;
- EN ISO 15614-12 about spot, seam and projection welding for metallic materials;
- AWS D1.1, D.1.2, etc. – Structural Welding Code;
- AWS B2.1 / B2.1M – Base Metal Grouping for Welding Procedure and Performance Qualification;
- Sezione IX del codice ASME “Boiler and Pressure Vessel Code”;
- EN 13134 about brazing procedure approval.