DOUBLE-ACTING HYDRAULIC ACTUATOR WITH DIFFERENT PUMPS FOR EACH ACTUATION DIRECTION

摘要

An actuator operable to move a valve stem between an opened position and a closed position includes a cylinder including an open side and a close side, the cylinder coupled to the valve stem, a first pump connected to the cylinder and operable to deliver a first high-pressure fluid to the open side of the cylinder to move the valve stem toward the opened position, and a second pump separate from the first pump, the second pump connected to the cylinder and operable to deliver a second high-pressure fluid to the close side of the cylinder to move the valve stem toward the closed position.