PVC Check Valves
A PVC check valve allows for the release of pressure from a pressurized system without the creation of backflow back into the system. These valves are commonly used in situations where backflow could create damage or contamination, such as in filtration or pumping systems. They are designed to work automatically, preventing damaging flow at critical times. These affordable valves are easy to replace and easy to clean. Because the internal components can be removed, maintenance is simple and affordable without tearing apart the entire system.
PVC check valves come in true union ball check, wafer check and swing check designs. All offer the benefits of PVC, including its durability and corrosion resistance. True union ball check valves have a metal or ruby ball that turns flow on and off when the pressure inside the valve reaches a certain point. The pressure pushes the ball into the "off" position. Because these valves can be quite small, they are used in microelectronics, but also may be used in chemical processing, water treatment and chemical cooling processes.
Swing check valves contain a disk on a hinge that swings into place to stop reverse flow. They, like the ball check valves, are designed to work without human intervention. They are larger in size than ball check valves, so they are commonly used in larger applications, like the flapper in a home toilet, which opens is automatically held in the "off" position unless someone flushes and opens it. They may also be used in fire safety systems and firefighting equipment.
Wafer check valves are used in situations where the valve needs to open and close quickly. These valves, which are also called dual plate check valves, have a pair of plates that come together to stop the flow quickly. The plates stop flow automatically when the pressure in the system reaches a certain point.