Welding procedure qualification and welding test plates
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I have a gentle question: according to GB150 and relevant standards, welding test plates are not required for every container. So, is welding procedure qualification necessary for each container before it is manufactured, or is it only carried out when welding test plates are used? Thank you so much!
These are two different concepts. GB150 and regulatory requirements stipulate that for all welded joints of pressure vessel components, or those that are welded to such components, there must be corresponding weld procedure qualification as a basis; only with such qualification can pressure vessels made from specific materials be manufactured (under regulatory oversight). Weld test plates, on the other hand, are related to specific equipment, and their production is carried out based on the welding procedures appropriate for the material of the vessel shell. In short, the welding procedure qualification is carried out in accordance with JB4708, while the welding test plates are subject to JB4744 ； Take a closer look
Welding procedure qualification is a prerequisite for welding major pressure-bearing components; it represents an assessment of the company’s theoretical welding procedures. Each welding procedure qualification has a specific scope, and it can be applied to all weldings within that valid range. Reference can be made to JB4708-200. Product welding test plates are used to check whether the mechanical properties of the weld joints produced using the specified welding procedures meet certain requirements. The test plates you are referring to are likely product welding test plates. If batch substitution is not permitted, then at least one test plate should be included in each product manufactured, although it may also be necessary to use multiple plates. The exact number depends on the requirements outlined in the relevant standards
It’s not necessary to do it for each unit; since the materials are the same, there’s no need to proceed
I believe that weld procedure qualification is an assessment to determine whether the established welding procedure meets the specified requirements; if it passes this assessment and no conditions change during production, it can be used for the manufacturing of all containers in the organization.
Conduct a process evaluation first. 1. Reason: Process qualification is the experimental process and evaluation of results carried out to verify the correctness of the welding process designated for the weldments. Welding procedure specification (selected welding process parameters), experimental procedure (including physical and chemical tests), and result evaluation: this refers to the process qualification report, which verifies the correctness of the welding procedure specification through physical and chemical tests. 2. Only after process qualification has been carried out can the welding equipment be used with the appropriate process parameters. Either, how do you determine the parameters for your welding process, and how do you know if they are correct? 3. For product test boards, unless batch processing is used in place of individual testing, at least one test board should be produced for each product.