Overview G4658 pneumatic piston valve is a two-stage cut to achieve a two-step or two-step opening of the shut-off valve closing operation, is a more advanced pneumatic actuators. It consists of ball valves, piston actuator, solenoid valves, check valves, quick exhaust valves and other components. Since the actuator is a quick exhaust inside and throttle function, so two ball has very excellent switching characteristics. So that the opening and closing is slowed down, so that the pipeline fluid changes smoothly, the impact will not produce water hammer phenomenon makes an explosion of flammable fluid, it will not be damaged due to the impact of the system flow meter and other instruments, making it suitable for oil , chemical industry, light industry, national defense and other sectors of the flow control system, especially for oil storage and transportation system.