the pneumatic membrane valve mechanism are as follow: Pneumatic diaphragm control valve by the pneumatic membrane actuator mechanism and a valve body is composed of two parts, body structure is generally straight stroke type, the common part are single seater, two seater, sleeve, angle, three links, skateboarding, diaphragm structure. it is mainly by the valve cover, valve core, valve seat, valve stem, stuffing box, etc.. Upper end of the valve rod and thin film institutions push rod connected to the lower end, putting drives the valve rod to move, so that spool movement, changing the flow of fluid between the spool and the valve seat area, thus changing the flow of the fluid, to achieve the purpose of regulating.
Pneumatic valve mechanism is using the compressed air driven gate, when gate is closed, the sealing surface can only rely on media pressure to seal, that is, to rely on medium pressure of the gate sealing surface pressure to the other side of the seat to ensure the sealing surface of the seal, which is self sealing. Most of the valve is forced to seal, that is, when the valve is closed, it should rely on external force to force the flashboard to the valvet seat, in order to ensure the sealing surface of the seal.
1. Control valve selects single seat or double seat and has no special direct contact to kV , usually before and after the valve pressure is differed larger to choose two seat, generally a single seat is ok, because the two seater have two sealing line and leaked level of decline in the extent and the single seat valve. 2 control valve KV has been completed after the completion of a very critical step, in addition it has many parameters to calculate, there are following points: A. the calculated kV is called calculate KV, and you need to calculate the rated KV, usually the KV is rated KV 1\3~2\3. After getting the rated kV, select the rated KV in the vicinity of the valve
When the gas chamber input 0.02 to 0.10 MPa pressure signal the membrane is to produce thrust. The thrust plate moves downwards, compression spring, drive the push rod, a valve rod, a valve core moves downward, and the valve core leaves the seat, so that it compressed air circulation.
