Diaphragm Valve

Diaphragm Valve

Diaphragm valves (or membrane valves) consists of a valve body with two or more ports, an elastomeric diaphragm, and a “weir or saddle” or seat upon which the diaphragm closes the valve. The valve body may be constructed from plastic, metal, wood or other materials depending on the intended use. There are two main categories of diaphragm valves: one type seals over a “weir” (saddle) and the other (sometimes called a “full bore or straight-through” valve) seals over a seat. In general, straight-through diaphragm valves are used in on-off applications and weir-type diaphragm valves are used for control or throttling applications.


Diaphragm Valves find application in Water treatment plants, fertilizer, Petrochemicals industries, Chemical industries, Refineries, Thermal power stations, Brewery Industry and other process industries. Equally suited to on and off, or flow control applications, a diaphragm valve will handle positive pressures or high vacuum.


Size : 1″ – 12″ (25mm – 300mm)

Desige Code : BS 5156

Pressure Rating : PN 6 – PN 1.0 – PN 10 – PN 16

MAT. OF CON. : CI / CS / SS / Alloy20 / Monel / Hastelloys other exotic materials Actuation : Handle Wheel, Pneumatic Cylinder

Depending on temperature, pressure and chemical resistance, one of the following is used:

Body Lining: Unlined/ NR / BUNA-N EPDM / Ebonite / Neoprene / FRP / PTFE / Butyl / FEP/ PFA / PO / PP / Tefzel / KYNAR / XYLON / HALAR / Glass Lined (Green Glass or Blue Glass)

Body Diaphragm: EPDM / Ebonite / Neoprene / FRP / PTFE / Butyl/ Silicone / Viton / NR /FEP, with EPDM backing / PTFE, with EPDM backing / PFA, with EPDM backing

Flange Drilling: ANSI B 16.5 / BS 10 / DIN / JIS as per customer’s requirement.

Testing : BS 6755-1