1 Test Case
    According to GB / T 13927 of the regulations.
2 No-load operation test
    Drive is directly installed in the valve, the valve configuration using the design of the drive unit from fully closed to fully open and then to fully closed loop operation of butterfly valves open and close 3 times, check valve operation is normal.
3 Sealing test
    According to GB / T 13927 of the regulations.
4 disc bearing capacity test
    Closed inlet valve, so valve horizontally, exports upward direction. Following the valve sealing surface is full of water, close the valve, water pressure applied from the inlet to 1.5 times the maximum allowable working pressure, continuous test pressure not less than 10 min. Then, observe the situation of the disc.
    Note: This item test pressure, if the leak sealing surface, not as a basis to judge sealing test failure.
5 Measurement of shell thickness
    With a thickness or caliper body dedicated channel and the stem wall thickness of shaft position.
6 Hardness Measurement of stem
    Stem ends with a hardness in the Ministry of measurement, the measurement of three-point averaging.
7 Material composition analysis
    In the body of the body on the sampling, sample cuttings should be 6.5 mm below the surface Department.
8 Body Material Mechanical Properties
    Furnace with a valve body with the number, the same batch of heat-treated test bars according to GB / T 228 under way.
9 Check Valve Logo
    Visual body marking the surface of cast or the content.
10 nameplate content inspection
    Valve nameplate marking visual content.