Fluorine lined diaphragm valve is a special type of valve with cut-off function. Its opening and closing parts are composed of steel valve disc and diaphragm made of soft material (rubber and fluoroplastic composite), and the inner cavity of the valve body is connected with the valve cover. The lumen is separated to achieve the purpose of cutting off the medium in the tube.
- The composite diaphragm separates the inner cavity of the lower part of the valve body from the inner cavity of the bonnet, and forms a direct-flow channel with it, so that the internal parts such as the valve stem and disc on the upper part of the diaphragm are completely isolated from the medium, and the packing sealing structure is omitted. Both internal leakage and external leakage can be avoided at the same time.
- Diaphragms made of PFA or PCTFE and synthetic rubber and valves with Feflon fluoroplastic linings are suitable for various strong corrosive media except “molten alkali metals and elemental fluorine”.
- The diaphragm as the actuator is prone to fatigue fracture due to frequent opening and closing, and should be replaced regularly according to the working conditions and medium characteristics.