The new welding process qualification standard ISO 15614: 2017 was officially announced and implemented in June 2017.
Welding process is an important measure to ensure the quality of welding. It can confirm the correctness and rationality of the welding process guidebook prepared for various welded joints.
Introduction to welding process qualification:
Welding Procedure Qualification Record (WPQR) The test process and result evaluation to verify the correctness of the proposed welding process or to perform welder capability assessment.
Purpose of welding procedure qualification:
1. Evaluate whether the welding unit is capable of welding the welded joints that meet the requirements of relevant national or industry standards and technical specifications.
2. Verify that the welding process instruction drafted by the welding organization is correct.
3. Provide a reliable technical basis for the formulation of a formal welding process instruction book or welding process card.
4. Assess welder ability.
Application scope of welding process qualification:
1.Suitable for the manufacture, installation and maintenance of steel equipment such as boilers, pressure vessels, pressure pipelines, bridges, ships, aerospace, nuclear energy and load-bearing steel structures.
2. Suitable for welding methods such as gas welding, electrode arc welding, tungsten argon arc welding, melting electrode gas shielded welding, submerged arc welding, plasma arc welding, and electroslag welding.
Welding procedure qualification steps:
(1) Prepare a power of attorney for welding procedure qualification.
(2) In accordance with the welding process qualification standards or design documents, prepare a welding process instruction or assessment plan, and preliminary processes.
(3) Preparation of test pieces, welding, weld inspection (heat treatment), sampling and processing, and test samples shall be carried out in accordance with the prepared welding process instruction (or preliminary process).
(4) Evaluate according to the required service performance; if the evaluation fails, the proposed welding process instruction or preliminary process should be revised and re-evaluated.
(5) Arrange welding records and test reports, and prepare welding process qualification reports; the qualification reports should record the process procedures, welding parameters, inspection results, test data, and evaluation conclusions in detail. Into the technical file.
(6) Based on the welding procedure assessment report, combining welding construction experience and actual welding conditions, prepare welding procedure specifications or welding work instructions, and process cards. Welders should strictly follow the welding operation instructions or process cards.
There are many standards for welding process assessment, Chinese, foreign, pressure vessel, steel structure. In fact, no matter which standard is used, the test plate is welded first, and then various tests are performed to verify the qualification of the process.
Welding procedure qualification test items
Visual inspection
2. Non-destructive testing, including RT-ray testing, MT magnetic particle testing, PT penetration testing, UT ultrasonic testing, etc.
3. Physical and mechanical properties test: tensile, bending (back bending, face bending, side bending), impact, hardness, etc.
4. Macroscopic metallography (residue, penetration, fusion degree, etc.)
5. Corrosion projects (SSC stress corrosion, intergranular corrosion, etc.)