The working principle of the pneumatic valve is that the pneumatic control valve consists of an actuator and a regulating mechanism. The actuator is the thrust component of the regulating valve, which generates corresponding thrust according to the size of the control signal pressure to push the regulating mechanism to move. The valve body is the regulating component of the pneumatic control valve, which is in direct contact with the regulating medium to adjust the flow of the fluid.

General requirements:

1. The specifications and categories of pneumatic valves should meet the requirements of the pipeline design documents.

2. The model of the pneumatic valve should indicate the national standard number required. If it is an enterprise standard, the relevant instructions for the model should be indicated.

3. The working pressure of the pneumatic valve is required to be ≥ the working pressure of the pipeline. Under the premise of not affecting the price, the working pressure that the valve can withstand should be greater than the actual working pressure of the pipeline; any side of the pneumatic valve in the closed state should be able to withstand 1.1 times the valve working pressure value without leakage; when the valve is open, the valve body should be able to withstand the requirements of twice the valve working pressure.

4. The manufacturing standard of the pneumatic valve should indicate the national standard number based on it. If it is an enterprise standard, the enterprise document should be attached to the purchase contract. Pneumatic valve standards are divided into three specifications: national standard, American standard and Japanese standard.

5. The complete description of the pneumatic valve includes its specifications, dimensions, materials, connection methods, and action methods (the action methods are divided into 1: double-acting, 2: single-acting).