What is the role of a check valve in a piping system?

The role of a check valve in a piping system is to allow fluid to flow in one direction while preventing backflow. This function is crucial in many applications to maintain the correct flow direction and prevent the reverse flow of fluids, which can lead to system inefficiencies, contamination, or damage.

Check valves achieve this by using a one-way mechanism, such as a disc or ball that moves with the flow, allowing it to open and pass fluid in the intended direction. When the flow attempts to reverse, the valve closes, effectively creating a barrier that stops the backflow. This is particularly important in systems where backflow could introduce contaminants or cause system pressure issues.

Other choices do not accurately describe the function of a check valve. For instance, it does not regulate flow speed, mix fluids, or filter impurities, which are the primary roles of different types of devices or components within a piping system.