What are the principles of valve pressure testing equipment?

Valve before use, it is necessary to use the top pressure vertical valve test equipment to test the relevant pressure, so what are the principles of pressure test? Following the valve pressure test equipment manufacturers look together.

1. After installation, the valve shall be tested for strength and tightness. Low pressure valve sampling inspection 20%, if unqualified should be 100% inspection; Medium and high pressure valves should be 100% inspected.

2. Generally, the valve shall not be tested for strength, but the body and bonnet repaired or corroded shall be tested for strength. For safety valve, its constant pressure and back pressure and other tests should comply with its specifications and related regulations.

3. The pressure shall be gradually increased during the test, and it is not allowed to increase the pressure sharply and suddenly.

4. Try to remove valve air during hydraulic test.

5. During the test by top pressure vertical valve test machinery, the valve should be installed in the direction that is easy to check.

6. For the valve in the form of welded connection, if the pressure test fails with blind plate, it can adopt conical seal or o-ring seal for pressure test.

7. The duration of strength test and sealing test is generally 2~3min, important and special valves should last 5min. Small diameter valve test time can be correspondingly shorter, large diameter valve test time can be correspondingly longer. During the test, the test time can be extended if there is any doubt. Do not allow sweat or leakage of body and bonnet during strength test. The sealing test, the rotor pump general valve only once, the safety valve, the high pressure valve and so on need to be carried out twice. During the test, small amount of leakage is allowed for low-pressure, large-diameter unimportant valves and valves that are allowed to leak according to regulations. As the general valve, power station valve, Marine valve and other valve requirements are different, the requirements for leakage should be in accordance with the relevant provisions.