Limit on the number of repairs at the same location on a weld

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There aren’t many projects these days, so I take some time to learn* a bit*. After reading Teacher Li Shiyu’s \"Training Manual for Pressure Vessel Design Engineers,\" I gained a deeper understanding of the limits on the number of times a weld in the same area can be repaired. I saw in the tutorial that this requirement is a special stipulation of China’s standards. The main reason for the repeated repairs to the same weld area in our country is the lax enforcement of welding process standards. There were previous concerns that repeated repairs to the same weld area could lead to grain growth due to repeated heating, thereby affecting the safe operation of the container. However, numerous tests have shown that there is no significant tendency for grain growth as a result of repeated repairs, and this does not pose a threat to the safe operation of the container. Therefore, it is unfounded to declare such a weld defective when it has been repaired more than 2 times in the same area. For the above reasons, China’s standards do not make it mandatory to limit the number of times a weld can be repaired in the same area; therefore, the phrase “should not exceed 2 times” is used. Corresponding warning measures are specified for cases where more than 2 repairs are carried out: each repair must be approved by the technical director of the manufacturing unit, and the number of repairs, the locations involved, as well as details of the repairs must be recorded in the container’s quality certificate. The aim is to enforce strict discipline in welding procedures.