(1) Under normal circumstances, the valve is not tested for strength, but the valve body and bonnet of the valve body and bonnet or corrosion damage shall be tested for strength after repair. For safety valves, the constant pressure and return pressure and other tests shall comply with the specifications and relevant regulations.

(2) The valve installation shall be tested for strength and tightness. The low pressure valve is checked by 20%. If it is not qualified, it should be 100% inspection; the medium and high pressure valves should be checked 100%.

(3) When testing, the valve installation position should be in the direction of easy inspection.

(4) Valves in the form of welded joints, when the test is not possible with the slab, the taper seal or O-ring seal can be used for pressure test.

(5) The valve air should be excluded as much as possible during the hydraulic test.

(6) The pressure should be gradually increased during the test, and it is not allowed to pressurize sharply and suddenly.

(7) The strength test and the seal test duration are generally 2-3 min, and the important and special valves should last for 5 min. The test time of the small-diameter valve can be correspondingly shorter, and the test time of the large-diameter valve can be correspondingly longer. During the test, the test time may be extended if in doubt. Not allowed during strength test The body and bonnet are sweating or leaking. For the sealing test, the valve is generally only used once, and the safety valve, high pressure valve and other raw valves need to be carried out twice. During the test, a small amount of leakage is allowed for low-pressure, large-diameter unimportant valves and valves that are allowed to allow leakage; since general-purpose valves, power station valves, marine valves, and other valves have different requirements, the leakage requirements should be Execute according to relevant regulations.