Piping hydrostatic test exceeds design pressure
Thread Content
Hello everyone, when testing pipes under water pressure, if the test pressure is higher than the design pressure of the pipe, will it damage the pipe?
Design (operating) pressure < Integrity test pressure < Strength test pressure < Pipeline ultimate pressure (finite element simulation)
It won’t happen; there’s no need to worry. Just proceed with the pressure testing using the parameters specified by the designer.
No, the wall thickness of pipes is generally calculated based on the allowable stress of the material at the design pressure and design temperature, and then rounded up to the wall thickness value specified in the standards. Throughout the process, various allowances such as the allowable stress of the material and wall thickness are taken into account, resulting in the actual pressure-bearing capacity of the pipeline being much greater than its designed pressure. Therefore, the hydrostatic test will be carried out in accordance with the specification requirements, and there will be no problems.
During pipeline pressure testing, the test pressure for the pipeline should be 1.5 times the design pressure, plus an adjustment factor for temperature. The design pressure of a pipeline is not equal to the maximum pressure that the pipe material can withstand; calculations are carried out during the selection of materials for design purposes. For example, the test pressure for some pipelines is much higher than their design pressure. Several issues related to acetylene pipelines: http://bbs.hcbbs.com/thread-1281053-1-1.html (Source: Haichuan Chemical Industry Forum)
There are several similar discussion posts; the original poster might want to search and take a look. For example, http://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1279660
Go and take a look at the pipes; you’ll understand it once you calculate the burst test pressure for the pipe fittings. . Will this pressure test be damaged due to the pressure?
Of course not; the test pressure is generally equal to 1.5 times the design pressure. This is because the design pressure already takes into account a safety factor; it is not the calculated pressure.
So that means it’s okay to use overpressure occasionally, right? I remember one manufacturer saying during a tubing burst test that the pressure resistance of my tubing was higher than the recommended operating pressure value. However, we do not recommend it; in other words, in our sample, problems arose when the pressure was not below the recommended value, and we are generally responsible for that ； But if it’s too high, we’re not responsible.
This won’t happen; the water pressure applied to our pipelines is always 1.5 times the design pressure
Do not exceed the pressure limit. Piping pressure testing, strength testing, and leak testing before putting it into production are primarily used to inspect the welds. Exceeding the design pressure during operation is not allowed.