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　　Plug advantage
    1, the plug for the regular operation, open and close quickly, lightweight.
    2, small cock fluid resistance.
    3, the plug structure is simple, relatively small size, light weight, ease of maintenance.
    4, good sealing performance
    5, the flow direction restriction is not installed, the medium can be arbitrary.
    6, no vibration, low noise.

 

    Valve disadvantages:
    1, the gate in the opening and closing process there is always friction, so the operating torque, and the gate and seat sealing surface is easy to produce scratches, resulting in valve leakage;

    2, no self-test leak device (even if the installation of a small valve to achieve this functionality through two gate valves, can not achieve automatic detection function);

    3, for media containing particles of impurities, such as sand, deposited at the bottom of the valve, the shutter can not be completely shut in place, resulting in valve leakage is very serious, (this is the fatal flaw gate).