The function of the pneumatic cut-off valve is to open the conduction and close the cut-off. It is controlled by the solenoid valve. Therefore, the pneumatic shut-off valve must be matched with the solenoid valve and controlled by the solenoid valve.

The function of pneumatic control valve is to control the valve at any desired opening, which is controlled by the valve positioner. Therefore, the pneumatic control valve must be matched with the valve positioner, and the opening is controlled by the valve positioner. For some process requirements, when the equipment is abnormal, the valve is required to be in a safe state, such as fully open or fully closed. At this time, the solenoid valve will also be configured to cut off the air supply by the solenoid valve to make the valve in a safe state.

The difference between pneumatic cut-off valve and regulating valve is that the cut-off valve is a two position valve, which has only two states of on or off. The pneumatic control valve can not only be opened or closed, but also any opening of the valve can be controlled.