ACTUATION SYSTEM FOR A VALVE

摘要

A valve actuation system is provided for a valve of the type wherein at least two separate movements are utilized to achieve either opening or closing thereof. The actuation system includes a pair of hydraulic or pneumatic actuator units for automatically performing these two separate operations. An electrically energizable control valve is associated with each of these actuators for controlling the flow of a pressurized control medium therethrough to achieve actuation in the proper sequence for attaining the desired valve movement. A control circuit preferably comprises a plurality of switches responsive to the positions of these two valve actuators as well as the position, (viz., "valve open" or "valve close") of an operator accessible main control lever or switch. These switches deliver electrical power to energize the fluid flow control valves so as to automatically perform the correct sequence of actuator operations to open or close the valve, as desired.