Repair of pressure vessels made from foreign standard materials
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When dealing with pressure vessels made from foreign standard materials, what precautions should be taken during repair?
Too general, welding? Try to use materials of the same type, or those that perform better under the given operating conditions than the original ones; analyze each case on its own
This post was last edited by Pinocchio on 2016-12-9 09:04. If it involves the repair of pressure vessels within China, it is necessary to comply with the requirements set out in the relevant regulations, namely those in Chapter 5 of TSG21-2016, which deals with installation, modification, and repair. If repair refers to welding, the requirements regarding welding specified in the tolerance specifications must be met. For foreign materials, a welding procedure qualification must be carried out for each grade; the rest of the procedures are the same as those for domestic materials. Domestic materials can be grouped by base metal grade, and base metals in the same group can be combined for welding procedure qualification. For details, refer to NB/T 47014 \"Welding Procedure Qualification for Pressure Equipment\". In addition, the non-destructive testing after welding, post-weld heat treatment, and pressure testing must also meet the requirements of the code.
As a supplementary point: In accordance with clause B2.2 of NB/T 47014, a \"base material classification report\" is prepared based on the chemical composition, mechanical properties, and welding characteristics of the material; in such cases, foreign materials can also be classified into the corresponding categories of domestic materials, eliminating the need to conduct welding procedure evaluations for each specific grade.
According to the original poster, it should be some imported equipment, or equipment manufactured by domestic manufacturers in accordance with foreign standards; it’s not just the fact that the materials are of foreign origin. For equipment that complies with typical ASME standards, repair work must first be carried out by a unit that possesses ASME qualifications for manufacturing and repair, following the requirements of ASME standards.