Butterfly valve pressure test method.
The strength test of the pneumatic butterfly valve is the same as that of the cut-off valve. When testing the sealing performance of the butterfly valve, the test medium should be introduced from the end of the medium flow, the butterfly plate should be opened, the other end closed, and the injection pressure reached the specified value; after checking that the packing and other seals are not leaking, close the butterfly plate and open On the other end, check whether the butterfly plate seal is qualified. The butterfly valve used to adjust the flow may not be tested for sealing performance.
Diaphragm valve pressure test method.
The strength test of the diaphragm valve introduces the medium from either end, opens the valve flap, and closes the other end. After the test pressure reaches the specified value, check whether the valve body and the valve cover meet the requirements. Then drop to the test airtight pressure, close the valve flap, and open the other end to check that it is qualified and there is no leakage.
Pressure test method of one-way valve.
Check valve test state: the axis of the poppet check valve flap is perpendicular to the horizontal direction, and the axis of the swing check valve channel and the flap axis are roughly parallel to the horizontal direction.
During the strength test, introduce the test medium from the inlet end to the specified value, close the other end, and observe whether the valve body and bonnet are leaking.
The air tightness test is to introduce the test medium from the outlet, and check that there is no leakage at the sealing surface, packing and gasket at the inlet end, which meets the requirements.
Safety valve pressure test method.
②The strength test of the safety valve, like other valves, is a water test. When there is pressure at the lower part of the test valve body, it is introduced at the inlet I=I end and introduced on the sealing surface; when there is pressure at the upper part of the test valve body, it is introduced on the bonnet, introduced at the El end, and closed at the other end. What meets the requirements is that the valve body and bonnet do not leak within the specified time.
②Air tightness test and constant pressure test, generally used medium is: 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. In some important positions, the safety valve usually uses nitrogen as the test medium.