The diaphragm valve diaphragm valve is a special form of cut-off valve, appeared in the 1920s. Its opening and closing parts of a piece of soft material diaphragm separates the body cavity of the valve cover cavity and drive components, it said diaphragm valve. 
 The diaphragm valve features are as follows: 
 The most prominent feature is to divide the lower part of the body cavity and the upper valve cover cavity separated in the diaphragm at the top of the stem, the valve and other parts from the corrosive medium, eliminating the need for packing seal structure, and does not generate media leaks . 
 A soft seal such as rubber or plastic membrane produced better sealing. Periodic replacement of the diaphragm for the wearing parts should be depending on the medium characteristics. 
 2, subject to the restrictions of the diaphragm material, diaphragm valves for low pressure and high temperature applications. 
 3, the diaphragm valve structure can be divided into: housing type, DC type, globe type, straight-through, the ram type and the right angle six; connection usually in the form of flange connections; manual, electric and pneumatic drive can be divided into Among these three, pneumatic drive is divided into normally open, normally closed and reciprocating three kinds. 
 Are not generally suitable for temperature higher than 60 degrees and transportation pipeline in organic solvents and strong oxidizing media, should not be used in the high pressure piping. 
 Nominal pressure: PN0.5-16Mpa 
 Operating temperature :0-550 ℃ 
 Nominal diameter: DN15-150mm 
 Connection type: flanged, threaded, welded 
 Material: 304,316,304 L, 316L, SS316, WCB, WC6, WC9, CF3, CF8, cast steel, cast iron, ductile iron, forged steel, stainless steel and so on.