The structure of the gate valve is relatively simple, mainly composed of the valve body, gate, valve stem and sealing components. The gate is a key component of the valve, usually of cast iron, carbon steel, stainless steel and other materials, the top and bottom are connected to the valve stem and the valve seat. The sealing characteristics of the gate valve mainly depend on the surface between the gate valve and the valve seat. These surface contacts are usually specially treated, such as grinding and polishing, to ensure its flatness and smoothness. When the gate is lowered and adapted to the location of the valve, a reliable seal can be formed to prevent average leakage.

The gate valve has the characteristics of simple design, good tightness and small flow resistance. It is suitable for shutdown in high pressure and ultra-high pressure conditions, as well as in cases requiring strict sealing. However, the gate valve is not suitable for use as a throttle, because a long time in the semi-open state can aggravate the wear of the shutter and valve seat.