Definition - What does Check Valve mean?
A check valve is a flow-monitoring device typically used in pipeline systems to allow a fluid to flow in only one direction and prevent backflow or backwash. They can be used for a variety of fluid applications such as liquids, gases, condensate or slurries.
Corrosionpedia explains Check Valve
Check valves operate based on flow sensitivity to activate opening or closing. They are primarily composed of two discs - one allowing a forward flow, and the other restricting backward flow by closing the valve when the fluid flow rate decreases or fluctuates.
A key disadvantage of check valves is that they cannot be used in pulsating systems because the continuous irregularity in flow due to vibrations would result in the valve prematurely preventing a forward flow operation.