What to do if the re-inspection of the test plates for pressure vessel products is still unsatisfactory?
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What to do if the re-inspection of the test plates for pressure vessel products still fails? This post was last edited by yyong110 on 2008-3-11 09:07.]
If the welding test plates still fail to meet the requirements, it is necessary to examine the choice of welding materials and the appropriateness of the welding process, among other factors; manufacturing pressure vessels cannot proceed until they meet the standards
Article 77, paragraph 4.(9) of the Standards specifies that if a product’s welding test piece fails, it is permissible to carry out repairs; such repairs must comply with the provisions of Article 71. If repairs are not undertaken, it is possible to take samples from areas free of defects and conduct the tests again.
Re-inspection fails; test samples fail; the product fails. Considering lowering the standards for use, or scrapping it, is undoubtedly the right choice!
You are referring to the issue of unsatisfactory appearance; by the time re-testing is carried out, it already involves physical and chemical property tests such as tension, bending, and impact tests. It has no guiding value!
If even the test plates fail, how can the welds on the equipment be successful! ! If there is no problem with the materials (base metal, welding material), then it must be a problem with the welding process. I don’t think the welder would act carelessly when testing the plates; they will adjust the welding process until satisfactory results are achieved. Otherwise, the equipment cannot be welded
Product test pieces are welded under the same conditions as the actual products. What I’m referring to here is the requirement in the specifications regarding re-inspection of these test pieces; according to those specifications, if a test piece fails, it can be repaired, re-inspected, or subjected to heat treatment until it meets the requirements. But once the product has been manufactured, it’s not possible to go through such processes with that product as well, right?
I don’t understand the issues everyone is discussing; please, experts, explain in detail! ! I suggest that experts from manufacturing plants, quality control personnel, and inspectors from boiler inspection agencies participate in the discussion
Welding test plates are used to evaluate welding processes. After being welded by certified welders, these test plates undergo non-destructive testing, and only upon passing such testing can physical and chemical experiments be carried out. If the non-destructive testing fails, the work must be repaired or a more skilled welder should be employed to carry out the welding again. If defects exceeding acceptable limits remain, it is necessary to consider whether there are issues with the welding process, such as the choice of welding electrodes, groove preparation, current and voltage settings, welding method, preheating and cooling procedures, and hydrogen removal treatments. If the XT test is successful but the physical and chemical tests fail, the sample can be replaced and tests such as tensile and bending tests can be conducted again. If it is confirmed that the required performance standards cannot be met, the welding process must be modified and a new weld assessment performed. Through the above process, the probability of the test plates welded along with the products being defective is very low, or even non-existent. If defects do occur, it must be due to a problem at some stage in the process. If the test plates are defective, then the products are also defective and cannot be shipped. As mentioned on the 4th floor, it is possible to consider using them to lower standards, or to discard them. This post was last edited by q235b on 2008-3-23 18:22]
What specific aspects of the project are not up to standard? There are many factors that can lead to non-compliance – it could be that the test samples themselves are defective, or there might be misjudgments. What was said upstairs is very comprehensive; it’s worth learning from! !
If, even when sampling from product test plates is carried out in full compliance with relevant regulations, the re-inspection of those test plates still yields unsatisfactory results, such products should be scrapped. And investigate the reasons for the scrapping to prevent similar situations from occurring again.