Questions regarding the pressure for leak testing of industrial valves according to GB/T 13927-2008?
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As stated in the title: In the standards: “4.7.3.2 When the test medium is gas, the test pressure is 0.6 MPa ± 0.1 MPa”； When the nominal pressure of the valve is less than PN10, the test pressure is 1.1 times the maximum allowable operating pressure of the valve at 20°C (1.1×CWP). ” A problem has arisen now: the stop valves for chlorine purchased by the company (valves of PN25 and PN40 grades), which are manufactured in accordance with the standard GB/T 13927 and have a design pressure of 1.2 MPa, exhibit internal leakage when subjected to airtightness tests at pressures above 1.0 MPa. How should this issue be handled?
If the valve fails the leak test, contact the supplier or manufacturer to request a replacement; for use with substances such as chlorine/ammonia, it’s best to choose a reliable manufacturer
During pressure testing, the valve should be in the open position. Internal leakage is part of the leakage rate test, and valves with different sealing grades allow for different levels of leakage.
The pressure testing for globe valves is divided into shell testing, high-pressure sealing test, upper sealing test, and low-pressure sealing test. The testing medium for the low-pressure sealing test is gas, at around 0.6 Mpa; this test is not mandatory. However, the other three tests are required, and the testing medium for them is water. Housing test: The test pressure is 1.5×CWP. High-pressure sealing test: The test pressure is 1.1×CWP. Upper sealing test: The test pressure is 1.1×CWP