The most prominent feature is that the diaphragm separates the inner cavity of the lower valve body from the inner cavity of the upper valve cover, so that the valve stem, valve disc and other parts above the diaphragm are free from medium corrosion, the packing sealing structure is omitted, and the medium leakage will not occur.
The diaphragm made of rubber or plastic has good sealing performance. As the diaphragm is a vulnerable part, it should be replaced regularly according to the characteristics of the medium. Limited by diaphragm material, diaphragm valve is suitable for low pressure and relatively low temperature.
Diaphragm valve can be divided into six types according to its structure: house type, direct current type, cut-off type, straight through type, gate type and right angle type; The connection form is usually flange connection; According to the driving mode can be divided into manual, electric and pneumatic three kinds, among which pneumatic drive is divided into normally open, normally closed and reciprocating three kinds.
Pneumatic rubber lined diaphragm valve has been widely used in chemical, liquefied gas, water supply and drainage, food, pharmaceutical, power plant desulfurization, metallurgy, mineral, boiler steam system.
The biggest difference between pneumatic rubber lined diaphragm valve and other valves is that it adopts the structure without stuffing box; The rubber diaphragm can completely isolate the corrosive medium in the flow channel from all the driving parts, thus eliminating the disadvantages of “running, emitting, dripping and leaking” of common valves.
Due to the smooth flow passage and small flow resistance of diaphragm valve, a larger flow rate can be obtained.
There are many kinds of rubbers to choose from on the inner surface of the valve body. Therefore, it has superior corrosion resistance.
Because the seal is elastic rubber diaphragm. Therefore, it also has good sealing performance and minimum closing force.
Pneumatic rubber lined diaphragm valve is composed of valve body, valve cover, valve disc, valve stem, diaphragm and other driving parts.
The opening and closing of the valve is achieved by rotating the hand wheel. The upper end of the valve cover is marked with the display color that can see the opening or closing position of the valve to indicate the opening and closing stroke of the valve. When the hand wheel is placed clockwise, the hand wheel will move down, and the valve disc will drive the diaphragm down to cut off the passage; Otherwise, the valve will be opened and the color will be revealed.
Diaphragm valve standard: in accordance with the provisions of GB12239 and the requirements of BS5156.
Post time: Mar-22-2022