Wafer Check Valve

Wafer check valves, also known as dual-plate check valves, have two spring loaded half-moon shaped discs that rotate about their shaft. The disc plates are kept shut by a torsion spring. When fluid flows in a forward direction, the pressure of the fluid causes the disc plates to swing open, allowing flow. The check valve is closed by the spring as soon as flow ceases, before any reverse flow can occur.