Gate valve is the most widely used type of valve. It has the characteristics of simple structure, small size, light weight, low material consumption, small installation size, rapid opening and closing, 90° reciprocating rotation, and small driving torque. In pipeline engineering, gate valves are mainly used as cut-off media.

The opening and closing part of the gate valve is the gate plate, and its movement direction is perpendicular to the direction of the fluid. The gate has two sealing surfaces. The most common shape is wedge. The wedge angle will vary according to the valve parameters, usually 50°. According to actual needs, the gate can be made into a whole, called a rigid gate; it can also be made into a gate that can produce slight deformation to improve its craftsmanship and compensate for the deviation of the sealing surface angle during the processing. This kind of gate The plate is called an elastic gate.

The gate valve can only be fully opened and fully closed, but cannot be adjusted or throttled. When closing, the sealing surface can be sealed only by the medium pressure, that is, relying on the medium pressure to press the sealing surface of the gate to the valve seat on the other side to ensure the sealing surface sealing, which is self-sealing. Most gate valves adopt forced sealing, that is, when the valve is closed, external force must be relied on to force the gate plate to the valve seat to ensure the sealing performance of the sealing surface.

In addition, the gate plate of the gate valve moves linearly with the valve stem. This is called a lifting stem gate valve (also called a rising stem gate valve). Usually there is a trapezoidal thread on the lift rod. Through the nut on the top of the valve and the guide groove on the valve body, the rotating motion is changed into linear motion, that is, the operating torque is changed into the operating thrust.