Views: 0 Author: Site Editor Publish Time: 2020-10-05 Origin: Site
① The strength test of the safety valve is the same as other valves. It is tested with water. When testing the lower part of the valve body, the pressure is introduced from the inlet and the sealing surface is closed; when testing the upper part of the valve body and the bonnet, the pressure is introduced from the outlet and the other ends are closed. The valve body and bonnet are qualified without leakage within the specified time.
② For sealing test and set pressure test, the general use medium is: steam safety valve uses saturated steam as the test medium; ammonia or other gas valves use air as the test medium; water and other non-corrosive liquid valves use water as the test medium medium. For safety valves in important positions, nitrogen is often used as the test medium.
The sealing test shall be tested with the nominal pressure value as the test pressure, and the number of times shall not be less than twice. No leakage within the specified time is considered qualified. There are two leak detection methods: one is to seal the joints of the safety valve, and use butter to seal the thin paper on the flange of the outlet. The plastic plate or other plate seal is attached to the lower part of the outlet flange, and the valve is sealed by filling with water. It is qualified if the water does not bubble. The number of constant pressure and return pressure tests of the safety valve shall be no less than 3 times, and it shall be qualified if it meets the requirements. Various performance tests of safety valves refer to GB/T 12242-1989 Safety Valve Performance Test Methods.
