Materials
Materials of Body : Ductile Iron (GGG40, GGG50). Cast Iron (GG25), Stainless Steel

Materials of Disc : Stainless Steel. Nickel Plated, Ductile Iron, Ductile Iron Coated Plastic,

Titanium Steel, Copper Alloy etc

Materials of Seat : Ethylene-Propylene-Diene Monomer (EPDM), Polytetrafluoroethylene (PTFE),

Nitrile Rubber (NBR), Chloroprene, Chlorosulfonated Polyethylene (Hypalon),

Silicon, Fluoroelastomer (VITON) , Caoutchouc etc.

Materials of Stem : Stainless Steel. Carbon Steel ,2Cr13

A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing through a section of pipe.
The valve is similar in operation to a ball valve. A flat circular plate is positioned in the center of the pipe.
The plate has a rod through it connected to an actuator on the outside of the valve. Rotating the actuator turns the plate either parallel or perpendicular to the flow. Unlike a ball valve, the plate is always present within the flow,therefore a pressure drop is always induced in the flow regardless of valve position.

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