Principle and application range of diaphragm vacuum valve
Diaphragm vacuum valve is to use the valve stem to directly press the rubber diaphragm on the valve seat. Used to cut off or connect air flow. It is often installed between the pumped container and various low vacuum pumps. Its action principle is to rotate the handle to make the valve stem move downward, and press the rubber diaphragm directly on the valve seat to stop the air flow. Rotate the handwheel in the opposite direction, and the valve rod moves upward to drive the rubber diaphragm away from the valve seat and connect the air flow.
The valve body is made of aluminum alloy. It has the advantages of simple structure, light weight, small volume and good sealing performance. The diaphragm vacuum valve with nitrile rubber is used for the non corrosive gas on the front stage and pre pumping low vacuum pipeline and the temperature is - 25 ~ 80 ℃. The diaphragm vacuum valve with fluororubber can be used in high vacuum system with the service temperature ranging from - 30 ℃ to 150 ℃
The nominal diameters of diaphragm vacuum valves produced in China are 10 mm, 25 mm, 40 mm and 50 mm respectively. Among them, there are five types of GM type high vacuum diaphragm circumference: GM, GMC, gm-kf, gm-d-h (I) and gm-d-h (II). The difference lies in the form of valve connecting flange.