Regarding the helium leakage test method for pressure vessels in Appendix B of HG/T20584
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When manufacturing U-tube heat exchangers, our company conducts helium leak testing on the heat exchange tubes and tube sheet joints in accordance with Appendix B of HG/T20584. Appendix B specifies that the test pressure may be either 25% of the equipment’s design pressure or 0.103 MPa; we felt that this pressure was too low, so we wanted to increase it, but not above the heat exchanger’s design pressure. The standard requires a helium concentration of at least 10% by volume at the test pressure, and we increased this concentration to 50%. During the container manufacturing inspection, the inspector suggested that the test pressure for helium leak detection was too high; since the standard specifies a value that is \"not greater than\", it would be best to conduct the test in accordance with those standards. But I don’t quite understand why the standard requires “not greater than”; I would appreciate it if some experts could give me some guidance.
This standard specifies “it is possible,” that is, the lower limit. According to NB/T47013.8-2012 \"Leak Detection\", the testing pressure shall not exceed 1.15 times the design pressure.
This post was last edited by SDHZZXM on 2017-8-11 at 16:40. Why is it so much higher than the standard requirements? There’s no need.
Theoretically, higher pressure and higher concentrations make it easier to detect leaks; in order to prevent leaks, the test pressure is increased
Theoretically, higher pressure and higher concentrations make it easier to detect leaks; in order to prevent leaks, the test pressure is increased
With your reminder, I really do think this statement needs careful consideration. The more I think about it, the more I realize that it indeed represents the minimum requirement specified. But I still need to think it through carefully and convince the supervisor first
With your reminder, I really do think this statement needs careful consideration. The more I think about it, the more I realize that it indeed represents the minimum requirement specified. But I still need to think it through carefully and convince the supervisor first
Are specific requirements specified in the design drawings, such as which standard should be followed for helium leak testing? There are clear differences in the specifications for HG20584 and NBT47013, and clear design definitions are required
Appendix B of HG/T20584 is explicitly specified in the technical requirements for the drawings
GB/T 15823-2009 Non-destructive testing – Helium leak detection method