The compact pneumatic piston diaphragm control valve consists of a diaphragm valve and a pneumatic actuator. It uses compressed air as the power source to regulate the flow of fluid medium in process pipelines.

Due to the adoption of a valve body with a corrosion-resistant lining and a corrosion-resistant diaphragm, a structure without a stuffing box, a throttling element consisting of an elastic diaphragm, and a smooth valve body flow passage, the pneumatic diaphragm valve has the advantages of low drag force, high flow rate, no external leakage, convenience and reliability, as well as fire and explosion resistance. It is widely used in industrial automation systems for flow regulation of strong acids, strong alkalis, highly corrosive, high viscosity, particle-containing, fiber-containing, toxic, and non-polluting media.

The closing and opening of the diaphragm valve are achieved by the pressure from the pipeline acting on the reinforced rubber diaphragm. When the pressure medium enters the valve control chamber, the diaphragm is pressed down, closing the valve passage. When the pressure in the control chamber is discharged to the atmosphere or downstream pipeline, the diaphragm rises, and the valve passage is opened. The valve has no valve stem, sealing gasket, directional seat, etc. The only moving part in the passage is the diaphragm, so there is no rusting or seizure phenomenon, and it has higher stability. With various structural forms and control forms, it can be applied to various fluid control needs.