Valve actuator for e.g. shut off valve for offshore applications, comprises fixed piston and moving cylinder surrounded by tube

摘要

The actuator comprises a fixed piston (6) and a moving cylinder (8). A tube(11) is arranged concentrically to the cylinder and connected to the latter so that movement of the cylinder in its length direction causes the liner to rotate. The tube is connected to the valve. The piston is located inside the cylinder. A hydraulic or pneumatic connection (22) is provided.