What is the primary function of a check valve?

The primary function of a check valve is to permit the flow of liquid in one direction, which ensures that fluids only move in the intended direction of the system. This function is critical in preventing backflow, which could potentially cause contamination or damage to equipment. Essentially, check valves are designed to open when fluid flows in the desired direction and close automatically if the flow attempts to reverse, thus maintaining an efficient and safe system.

While the ability to prevent backflow is closely related and a significant consequence of how check valves operate, the defining characteristic lies in their purpose to allow flow in one direction only. This directional flow control is crucial in various applications, including piping systems, pumps, and process equipment, ensuring operational integrity and efficiency.