Is there anyone who knows the standards?

It seems to involve filling it with nitrogen at a certain pressure and using soapy water to check for air leakage. I’ve forgotten exactly what pressure to apply

What should the 12-hour pressure drop requirement not exceed?

Based on the operating pressure of the device, it is generally required that the pressure used for testing be 1.2 to 1.5 times the operating pressure. A holding pressure of over 4 hours is sufficient

By device and medium; you can check the design, as everything was set aside at that time

Code for Construction and Acceptance of Industrial Metal Piping Projects (GB50235—2010) 6.1 The pressure for the hydrostatic test is the design pressure. The pressure for the hydrostatic test is the design pressure; prior to the test, the pipes must be purged to ensure that their interior is clean and meets the required standards. Test pressure gauges should be installed at the highest and lowest points of the pressure testing pipeline system, with at least one gauge at each point. The temporary blind flange for testing should correspond to the test pressure. During testing, special care must be taken to minimize the chances of errors occurring in the piping system, as the release of energy stored in compressed air can pose potential dangers. Therefore, the scope and volume of the testing system should be reduced as much as possible. Soap solution for leak detection should be prepared before testing, and the formation of foam should be checked during the experiment. Inspection of the surrounding welds, valves, and pinholes. A. The pressure test should involve a gradual increase in pressure, reaching 50% of the test pressure level. B. Stabilize the pressure for at least ten minutes, then reduce it by 10%, choosing a larger amplitude. C. Perform a visual inspection of the piping system under this pressure. D. Gradually increase the pressure to about half of the maximum test pressure, and then increase it further in steps, by approximately 10% of the maximum test pressure each time, maintaining each pressure level for at least 5 minutes to compensate for pipe tension. E. Maintain at the test pressure for at least 10 minutes. F. Then reduce the test pressure to the design pressure, hold it at that level for at least 30 minutes, and inspect the pipe components, flanges, valves, and welds; if the pressure does not drop and there are no leaks, the tightness test is considered successful.

This post was last edited by Desert Poplar on 2017-7-10 at 11:15. The Code for Construction and Acceptance of Industrial Metal Piping Engineering (GB50235—2010) specifies that the pressure used for the pneumatic test should be the design pressure. Before conducting the pneumatic test, the pipes must be purged to ensure that their interior is clean and meets the required standards. Test pressure gauges should be installed at the highest and lowest points of the pressure testing pipeline system, with at least one gauge at each point. The temporary blind flange for testing should correspond to the test pressure. During testing, special care must be taken to minimize the chances of errors occurring in the piping system, as the release of energy stored in compressed air can pose potential dangers. Therefore, the scope and volume of the testing system should be reduced as much as possible. Soap solution for leak detection should be prepared before testing, and the formation of foam should be checked during the experiment. Inspection of the surrounding welds, valves, and pinholes. A. The pressure test should involve a gradual increase in pressure, reaching 50% of the test pressure level. B. Stabilize the pressure for at least ten minutes, then reduce it by 10%, choosing a larger amplitude. C. Perform a visual inspection of the piping system under this pressure. D. Gradually increase the pressure to about half of the maximum test pressure, and then increase it further in steps, by approximately 10% of the maximum test pressure each time, maintaining each pressure level for at least 5 minutes to compensate for pipe tension. E. Maintain at the test pressure for at least 10 minutes. F. Then reduce the test pressure to the design pressure, hold it at that level for at least 30 minutes, and inspect the pipe components, flanges, valves, and welds; if the pressure does not drop and there are no leaks, the tightness test is considered successful.

There are requirements regarding the leakage rate; that is, the pressure drop must remain within a certain range to be considered acceptable, and the effect of temperature on the pressure drop also needs to be taken into account.

Well, I just want to know what the acceptable leakage rate is