Check Valves are also known as Non Return Valve (NRV). They allow liquid to flow in one direction only and prevents back flow of media in the reverse direction. The purpose of check valves is to prevent process flow from reversing in the system which could damage equipment or upset the process.
They are commonly found protecting pumps in liquid applications or compressors in gas systems where backflow could cause the pump or compressor to shut down. The basic design of a check valve reduces backflow in a line.
As they have a simpler design, they can operate without human interaction and automation. They rely on the flow velocity of the fluid to open and close. The higher the flow rate, the more open the valve will be until it reaches it maximum, full open position.
