Have you checked the cast steel check valve recently? They need to be carefully maintained to ensure that fluids flow safely and prevent spills. Damage or wear can cause many problems. What systems do you have to ensure "healthy" check valves? We have simple guidelines for maintaining them. What is the purpose of the check valve? If you need fluid to flow through a pipe in one direction, you can't do without them. Check valves are designed with a two-way system with openings that allow fluid to pass through. After the flow has passed, the valve closes to prevent backflow. Check valves can also close automatically if downstream pressure is excessive.