Regulations on the number of times pipe welds can be repaired
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This post was last edited by small pad on 2019-8-27 at 15:26. If the weld of the pipe fails the inspection or there is a leak, it needs to be cut open and welded again. Are there any relevant specifications regarding such repair ports that specify how many times they can be repaired, and that after that number of repairs the port along with the fittings must be replaced?
Thank you for your reply! So the question arises: why, in the 2011 version as well, does the national standard GB50236 \"Code for Construction and Acceptance of Welding Works for Field Equipment and Industrial Piping\" state that \"any unacceptable defects detected during non-destructive testing of welds must be eliminated before re-welding can take place, and the re-welded areas must be inspected using the same methods specified originally until they meet the required standards.\" ”In other words, it seems that no matter how many times it is repaired, there is no problem submitting it. If we set aside the issue of substandard welding quality, does multiple welding actually have an impact on the quality of the weld joint?
Is it repair or cutting? There is a limit on the number of repairs allowed
My understanding is as follows: 1. The number of repairs to carbon steel pipe welds should not exceed 3 times, while for other types of pipes it should not exceed 2 times. 2. Any number of times exceeding the above limit requires approval from the project’s chief technical officer. Section 5.6.11 in SH 3517. 3. In 50236, repairs should be carried out until the part meets the requirements; if the welds need to be repaired more than 3 times, the fitting or pipe can be replaced to still achieve compliance with the standards. 4. Approving beyond the specified number of times – this tests the engineer-in-chief’s skills and sense of responsibility. If I were the chief engineer, I would prefer to replace the pipes or fittings; there’s no need to take on the corresponding responsibility. :lol
Multiple weldings have an impact on the microstructure. It’s best to do it in one go.
Yes, stainless steel: 2 times, carbon steel: 3 times; there are relevant specifications
In GB50236, clause 3.0.6 clearly states that the number of times a weld in the same area can be repaired should not exceed 2 times. . .