Check valves are automated in operation and designed to prevent reversaling of flow in fluid piping systems. The valves are balance open by the flow of fluid in the forwarding direction and are shut by back pressure of the fluid or by the weight of the closing mechanism or by a spring force. Variety designs are available as listed under.
The Check Valve is designed to preventing backflow. Fluid flow in the desiring direction opens the valve, while back flow forces the valve closed. The range of check valve sizes range from 50mm to massive units of 1200mm dia.