The gate valve is a valve that moves the shutter closure member in the vertical direction of the centerline of the passage. Generally, it consists of valve body, valve seat, valve stem, gate, valve cover and sealing ring. It can be converted into a variety of electric gate valves and pneumatic gate valves by means of transmission. Gate valve cannot be use for adjusted and throttled.

List of content for this article：

1. The gate valve working principle,

2. When the gate valve is closed,

3. When the gate valve is opening.

Gate valve working principle:

The gate of the gate valve moves linearly with the valve stem. Usually, the trapping rod has a trapezoidal thread. The nut at the top of the valve and the guide groove on the valve body convert the rotary motion into a linear motion, that is, the operating torque is changed.

When the gate valve is closed:

The sealing surface can be sealed only by the medium pressure, that is, the sealing surface of the ram is pressed against the valve seat on the other side by the medium pressure to ensure the sealing of the sealing surface, which is self-sealing. Most of the gate valves are forced to seal, that is, when the valve is closed, the external force is forced to press the gate to the valve seat to ensure the sealing of the sealing surface.

When the gate valve is opening:

When the gate lift height is equal to 1:1 of the valve's diameter, the fluid passage is completely unobstructed, but this position cannot be monitored during operation. In actual use, the apex of the valve stem is used as a mark, that is, the position where the valve is opened, as its fully open position. In order to consider the temperature change, there is a lock phenomenon, usually at the position of the opening to the apex, and then back to 1/2-turn as the position of the fully open valve. Therefore, the fully open position of the valve is determined by the position of the shutter (ie, stroke).