In a piping system, what is the primary function of a check valve?

The primary function of a check valve in a piping system is to prevent backflow. Check valves are designed to allow fluid to flow in one direction only. When the flow ceases or reverses, the valve's mechanism, typically a hinged disc or ball, closes to block the reverse flow. This is crucial in various applications to protect equipment, maintain system integrity, and prevent contamination in water distribution systems. By ensuring that fluids can only travel in a designated direction, check valves help maintain proper operational conditions and enhance the safety and reliability of the overall system.