Cast Steel Piston Check Valve Class150-1500 Spring Loaded Lift Disc

Piston check valves are also called lift check valves. They are essentially globe valves without the stem and top works, allowing the disc to respond to flow rates and direction. The disc has linear movement and is typically body-guided with conical seating surfaces. Springs can be added above the disc to provide more closure force when the disc returns to its closed position. Some manufacturers include externally attached equalizer piping to increase the disc opening with lower flows. The equalizer pipe is an open-pressure communication device that maintains equal pressure above the disc and in the piping downstream of the disc.

Depending on the valve body configuration (Y-pattern, angle, or T-pattern), the pressure drop could be close to that of a tilting disc check valve or much higher. The disc of this check valve design is stable in an open position and can be used with a wide range of flow rates.