Piston Valve

A piston valve is a device that is used to control the motion of a fluid along a tube or pipe by means of the linear motion of a piston within a chamber or cylinder. Piston valves are used for fully open or fully closed for on/off regulation on steam, gas, and other fluid services. These valves are mostly used on fluids which cause excessive seat wear. Piston valves are mostly actuated manually, but some-times other actuation modes such as hydraulic and electric are used. Piston valves are usually used where the valve body is permanently installed and to reduce maintenance. Piston valves are not designed for throttling applications and they must be used in fully opened or closed positions. When the valve is fully opened, only the bottom face of the piston is exposed to fluid and the rest of the body is protected by the upper sealing rings. So the sealing surfaces are protected from erosion by the fluid flow.