Regarding pipeline pressure testing
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For steam pipes with a working pressure of 1.5 MPa, what should be the pressure used for the hydrostatic test? I’ve looked up some information; some sources suggest 1.15 times the working pressure, others 1.25 times, and still others 1.5 times. I’m not sure which value is correct. The nominal pressure for the valves and wave compensators on these steam pipes is 2.5 MPa. If the test pressure is set at 1.5 times the working pressure, then it would be 2.25 times the nominal pressure. I wonder whether the valves and compensators can withstand such a pressure during the test. Thank you! ! !
Steam pipes do not require hydrostatic testing; instead, the quality of the welds must be checked, and the quality of the pipe material must also be ensured.
It is necessary to determine what category the pipeline belongs to and which design standards are applied; of course, corresponding acceptance standards should be used during hydrostatic testing. Different standards result in different coefficients as well
It is usually done at the test pressure specified in GB50235-97.
Steam pipes shall undergo strength testing in accordance with the requirements of GB50235-97. The test pressure shall be 1.5 times the design pressure; when the design temperature of the steam is higher than the test temperature, the test pressure shall be calculated using the following formula: Ps = 1.5P1/2, where Ps represents the test pressure (gauge pressure) in Mpa； P — Design pressure (gauge pressure) (MPa) ； 1——Allowable stress of the pipe material at the test temperature (MPa) ； 2 — Allowable stress of the pipe material at the design temperature (MPa). When 1/2 is greater than 6.5, use 6.5.
The pressure for the hydrostatic test is calculated using the formula from Floor 5. Wave compensators cannot be used in pressure testing!
First, figure out whether it is a strength test or a sealing test? If it is a strength test, then the test pressure should be 1.5 times the design pressure
The operating pressure is 1.5 MPa; so what is the relationship between the design pressure and the operating pressure? Should the test pressure be 1.5 MPa of the design pressure, or 1.5 times the operating pressure?
1. Valves on steam pipelines have specific requirements regarding production, installation, and pressure testing； 2. Wave compensators generally do not participate in pressure testing. 3. For the pressure testing of steam pipes, the same rules as those mentioned on the 5th floor apply. Steam pipes shall undergo strength tests in accordance with the requirements of GB50235-97; the test pressure should be 1.5 times the design pressure. When the design temperature of the steam is higher than the test temperature, the test pressure should be calculated using the following formula: Ps = 1.5P1/2, where Ps represents the test pressure (gauge pressure) in Mpa ； P — Design pressure (gauge pressure) (MPa) ； 1——Allowable stress of the pipe material at the test temperature (MPa) ； 2 — Allowable stress of the pipe material at the design temperature (MPa). When 1/2 is greater than 6.5, use 6.5. Of course, if the designer or the client has higher requirements, those can be followed.
I have this problem too. . . Learned* it