Principle of diaphragm valve: Diaphragm valve is a special form of block valve, appearing in the 1920s. Its opening and closing member is a separator made of a soft material, to seperate inner cavity of valve body and inner cavity of bonnet, so it is called as diaphragm valve. Features of diaphragm valve: The most prominent feature is to seperate inner cavity of lower valve body and inner cavity of upper bonnet so as to protect valve rod, valve clack and other parts above diaphragm from etching by medium. It save filler sealing structure, and medium will not leak. diaphragm made of rubber, plastic membrane and other soft sealing material has good sealing property. Because diaphragm is a wearing part, it should be replaced at regular intervals depending on the medium characteristics. Due to limitation of diaphragm material, diaphragm valve is suitable for low pressure and medium temperature. Diaphragm, according to structure, can be divided into: house, straight-flow, cut-off, straight-through, flashboard and right angle types. The connection form is usually flanged joint. According to drive mode, it can be divided into manual, electric and pneumatic types, among which pneumatic drive is divided into normally open , normally closed and reciprocating types.
Principle: Power drive screw with compressed air to make valve element move up and down and pull mebrane up and down movement to turn it off and on. Features: compact, simple, small, beautiful; switch with guide, smooth motion; little closing moment, long life, ≥30 million times; mebrane compaction can be automatically adjusted for uniform pressure and reliable sealing; install mebrane into valve element through pushing-in method which is easy to replace.
