AWP shut-off valves are designed for installation in industrial heating and refrigeration systems. They can be actuated with a handwheel or a ratchet that is assembled onto the stem. Rotating the stem clockwise will lower the valve disc onto the valve seat and therefore close the valve, counter-clockwise rotation will lift the valve disc and open the valve. AWP shut-off valves should only be operated in fully opened or fully closed positions. The picture shows a cutaway model with the valve disc in “closed” position. The stem sealing is provided by a threaded bush with spring-elastic PTFE ring. The valves are also equipped with a back seal so that when the valve is fully opened it is possible to replace the threaded bush and the seal.