The small pneumatic piston diaphragm regulating 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 the process pipeline.

Due to its structural design featuring a corrosion-resistant lined valve body and corrosion-resistant diaphragm, a packing-free structure, an elastic diaphragm as the throttling element, and a smooth valve body flow passage, the pneumatic diaphragm valve possesses advantages such as low drag force, high flow rate, no external leakage, convenience and reliability, as well as fire and explosion resistance. It is widely used for flow regulation in industrial automation systems for media that are strong acids, strong alkalis, highly corrosive, high viscosity, contain particles, fibers, and are toxic and not allowed to pollute.

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.