High-pressure gas chamber testing of valves
Thread Content
To assess the quality of cast valves, those with a nominal pressure of PN20 or less must undergo a high-pressure gas chamber test at a pressure equal to 1.1 times the nominal pressure of the shell. Why is it called a high-pressure gas chamber test? If water is used for the testing, the pressure applied is 1.5 times the nominal pressure, yet it isn’t referred to as a high-pressure water chamber test
For specific details, please check the valve pressure testing standards
A shell test is a pressure test conducted on the entire valve housing, which is formed by combining the valve body, valve cover, and other components. Its purpose is to test the tightness of the valve body and valve cover, as well as the pressure resistance of the entire housing, including the joint between the valve body and valve cover. The hydrostatic test is used to determine whether there are leaks in the valve. Moreover, it makes no sense for the original poster to insist that 1.1 times the pressure of gas is considered high pressure, while 1.5 times the pressure of water is not considered high pressure.
High-pressure gas tests involve considerable danger; calling them that is just to draw special attention! 1.1 times the atmospheric pressure and 1.5 times the water pressure do not refer to the nominal pressure, but rather the rated pressure.
:P Thank you all for your help; I finally understood it.
A water pressure of 1.5 times is what we generally refer to as shell strength; as for a gas pressure of 1.1 times, I’ve never encountered that before. . The typical pressure for valves is set at 0.6 MPa, which is used for low-pressure sealing tests. . An air pressure of 1.1 times the nominal pressure is actually very dangerous; most manufacturers are likely not capable of producing such conditions. .
Yes, a 1.1 times air seal – that’s an incredibly serious hazard! It’s basically not done unless a user really insists on it; and even if it is done, it has to wait until high-pressure gas cylinders are available, which is quite troublesome