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Welding procedure qualification is a process in which weld specimens are welded in accordance with the established welding procedure specifications, and through various inspections and tests, it is determined whether the weld joints produced under such procedures possess the required performance characteristics. The specific procedure is as follows. Preparation of welding procedure specifications: Before compiling welding procedure specifications, welding technicians should, based on the product manufacturing or installation drawings and relevant technical requirements, classify and summarize all welds that are to be welded using processes that have been deemed suitable, according to the categories of steel used. They should then take into account the welding procedure qualification tests that have already been conducted in the company. Following the procedures for welding procedure qualification, and with the aim of avoiding both repetition and omissions, they need to identify those tests that have not yet been carried out, as well as those that need to be repeated due to changes in conditions or parameters. An outline of the required welding procedure qualifications should be prepared, along with any specific qualification requirements for the product in question (if any). According to the welding procedure qualification checklist, welding technicians prepare welding procedure specifications for each item based on practical experience, relevant technical data, and the specific production conditions of the enterprise. If necessary, weldability tests can be conducted prior to preparation to determine the weldability of the materials, thereby providing a basis for drafting the welding procedure specifications. Welding test pieces 1) Welding should be carried out under the supervision of the chief welding engineer, so that any unexpected issues that arise during welding can be addressed promptly. 2) Welders with higher levels of operational skill should be employed to minimize human factors. Welding procedure qualification is used to verify whether the weld joints produced using a pre-determined procedure meet the required performance standards, rather than assessing the welder’s skill level. Choosing welders with a higher level of skill helps to avoid confusing the factor of welder competence with process-related factors, which could otherwise lead to unnecessary revisions of the process and subsequent re-evaluations. 3) Before welding, check the material certificates or retest reports for the steel and welding materials to ensure the validity of the evaluations. 4) Check the welding rod drying records and drying quality. 5) Ensure that the welding equipment and control devices in use are in good condition. 6) Clean the test piece in accordance with the process instructions, assemble the weld joints, and adjust the process parameters properly. 7) Welding must be carried out strictly in accordance with the requirements of the process instructions, and records of the original evaluation data must be kept. Inspect and issue a welding procedure qualification report. After welding is completed, inspections and tests are carried out; the inspection items include visual inspection, non-destructive testing, as well as tests on mechanical properties and bending strength ； The inspection items for fillet weld specimens include visual inspection and metallographic inspection (macroscopic). Inspection steps: 1) First, conduct a visual inspection, followed by non-destructive testing in accordance with standards; the test specimen must be free of cracks. 2) Prepare tensile specimens, bending specimens, and impact specimens as required (when specified); when taking samples, be careful to avoid areas with defects. 3) Conduct tensile tests, bending tests, and impact tests in accordance with standards to verify whether all performance parameters are satisfactory. Welding procedure card: After the welding procedure qualification is completed, welding technicians can use the results of this qualification to develop specific welding procedures and welding procedure cards. It should be noted that, as long as it remains within the scope of alternatives permitted by the regulations, multiple welding procedure cards (welding procedure guides for production) can be prepared based on a single process evaluation, or one welding procedure guide can be prepared based on multiple process evaluations.