AWP shut-off valves are designed for the installation in industrial heating and refrigeration systems. These shut-off valves are operated by an electric actuator which is connected to the stem. The picture shows an actuator with additional AUMATIC AC 01.2 control. To close the valve the actuator moves the stem clockwise which lowers the valve disc onto the valve seat. To open it the actuator moves the stem counter-clockwise which lifts the valve disc. AWP shut-off valves should only be operated in fully opened or fully closed positions. The stem sealing is provided either by a threaded bush (AVR type) or by a threaded bush with an additional metal bellows (AVB type) to ensure a complete hermetic sealing. The valves are equipped with a back seal. When the valve is fully opened, it is possible to replace the threaded bush and the seal.