A butterfly valve is a valve that isolates or regulates the flow of a fluid. The closing mechanism is a disk that rotates. A valve consisting of a disk rotating on an axis across the diameter of a pipe to regulate the flow, and consisting of a pair of semicircular plates that are attached to a spindle across a pipe and hinged to allow flow only one way.
Butterfly Valve types are Wafer, LUG, flanged in Body as per Cast Iron IS 210 Gr. FG 200 / ASTM A 216 Gr. WCB, S.G. Iron / S.S. 304 / S.S. 316 / FRP/ Disc, AISI 410 / 304 / 316 Spindle, Suitable for mounting between two flanges of ANSI – 150, Lever / Gear Operated/Pneumatic or Electric Operated, Valve as per BS 5155 / API 609