The shut-off valve, also known as the gate valve, is a forced-sealed valve, so when the valve is closed, pressure must be applied to the valve flap to force the sealing surface to not leak. When the medium enters the valve from below the valve flap, the resistance to be overcome by the operating force is the friction between the stem and the packing and the thrust generated by the pressure of the medium. The force of closing the valve is greater than the force of opening the valve, so the valve stem The diameter of the stem is large, otherwise the cast iron threaded shut-off valve will fail the top of the valve stem.

The following items should be noted for the installation and maintenance of the shut-off valve:

1. The handwheel and handle operated shut-off valve can be installed at any position of the pipe.

2. Handwheel, handle and aerodynamic mechanism are not allowed to be used for lifting.

3. The flow direction of the medium should be consistent with the direction of the arrow shown in the valve body.

Cut-off valve advantages:

1. The working schedule is small and the opening and closing time is short.

2. Good sealing performance, small friction between sealing surfaces and long service life.

3. The opening height is generally only 1/4 of the diameter of the seat channel, so it is much smaller than the gate valve.

4. Usually there is only one sealing surface on the valve body and the valve flap, so the manufacturing process is better and easy to repair.

5. Nominal pressure or pressure level: PN1.0-16.0MPa, ANSICLASS150-900, JIS10-20K