A check valve is a backflow prevention device: it allows flow in only one direction. The pressure of forward fluid flow opens the valve disc and the pressure from backflow closes it, forcing the disc against the valve seat. Three types of check valves are available to achieve this checking effect.
Swing Check Valve
A hinged disc assembly is suspended from the body to allow it to move freely. This configuration minimizes pressure loss and eases fluid flow. Swing check valves can be used for either horizontal or vertical (fluid flowing upward) pipe layouts.
Lift Check Valve
The structure of the lift check valve is the globe valve without the handwheel and any parts which related to manual operation. And have the cover in lieu of the bonnet. Because of its large fluid resistance, this valve is used primarily for small-bore applications.
Wafer Check Valve
Thanks to its wafer shaped design, this swing check valve is far thinner and lighter than conventional water hammer absorbing check valves. It features a built-in bypass circuit and superior closing action and is multifunctional high performance water hammer absorbing check valve.