Pneumatic actuator is a device that uses compressed air to drive valve switches or regulate medium flow. It is also called pneumatic actuators or pneumatic devices, and is generally used with valves.
Double acting pneumatic actuator:
Double acting pneumatic actuator is ventilation in case of pneumatic actuator starts to rotate to open the valve, when the valve is closed to the other side of the ventilation can be closed, is reset by air cylinder, when the loss of gas supply can only be maintained in situ; simply means that you give the gas, the pneumatic actuator starts to rotate open the valve. When the valve is closed, the other side to need to shut down! And the single effect is that you open the gas, not gas will automatically shut down!
In general operating conditions, double action is used more, and the double acting cylinder has no spring, so the cost is lower than the cost of the single acting pneumatic actuator.
Single acting pneumatic actuator:
Single acting pneumatic actuator in the ventilation condition of the pneumatic actuator to open the valve, gas barrier case automatically closed, single acting pneumatic actuator by spring automatic reset, the general is widely used in dangerous conditions, Besto delivery of combustible gas or combustible liquids, when emergency situations also appear in the lost source. Single acting pneumatic actuator can automatically reset to minimize the risk, and the double action is usually not easy to reset.
The single acting pneumatic actuator is usually divided into normally open and often closed type. Open type: ventilation, gas; normally closed type: ventilation, gas.