Issues regarding the determination of the pressure testing time and methods for heat exchangers
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GB151-1999 specifies the multiple relationship between the pressure applied to heat exchangers and the design pressure of the equipment, but it does not outline the specific duration for maintaining this pressure, nor does it specify the test pressure and time required after a leak in the tube bundle has been repaired. I remember having read something about this somewhere, but I can’t recall where; could someone please explain the specifics regarding the test time and the time needed to maintain the pressure? Thank you!
According to GB151, the pressure should be 1.1–1.25 times the design pressure; after maintaining this pressure for 10 minutes, it should be reduced to the design test pressure and held at that level for another 30 minutes. For shell-side pressure testing: during the hydraulic test, the pressure should be increased gradually. Once the test pressure is reached, the pressure-increasing valve should be closed, and the pressure should be maintained for no less than 10 minutes. After that, the pressure should be reduced to the design pressure and held for 30 minutes. All welds and joints must be inspected; no leaks or visible abnormal deformations are allowed to indicate success. If any abnormalities occur during pressure testing, the pressure should be released before taking action, and pressure testing should be repeated in accordance with the above requirements. Piping pressure testing: The pressure in the piping system should be increased gradually. Once the test pressure is reached, the pressure application valve should be closed. The pressure must be maintained for at least 10 minutes; thereafter, it should be reduced to the design pressure and held at that level for another 30 minutes. All welds and connection points must be inspected, and no leaks or visible abnormal deformations are allowed to indicate that the test is successful. If any abnormalities occur during pressure testing, the pressure should be released before taking action, and pressure testing should be repeated in accordance with the above requirements
I couldn’t find that text in the standards. Could you please send me your PDF version of the standards?
For this part, refer to GB/T150.4