Knife & Butterfly Valves (Industrial)
A butterfly valve is from a family of valves called quarter-turn valves. The "butterfly" is a metal disc mounted on a rod. When the valve is closed, the disc is turned so that it completely blocks off the passageway. When the valve is fully open, the disc is rotated a quarter turn so that it allows an almost unrestricted passage of the fluid. Butterfly valves incorporate a notch plate which allows you to position the disc incrementally in order to throttle the flow (usually about 10 positions).
Butterfly valves are available with a variety of end configurations, actuator styles, disc materials & resilient seat elastomers, all of which are determined by the specific application they're being used in. Butterfly valves can be found across many industries including industrial processing, water and waste water, dry bulk conveying, paper mills, light slurry handling, food and beverage, HVAC, transportation and more! For quick reference we've listed some of our more common styles & materials below.
Wafer & Lug-style butterfly valves are designed to be used with ANSI Class 125/150 flanges pipe flanges. Wafer style fits between the flanges and are held in place by the force of the mating flanges, while Lug style are bolted directly to the mating flanges from each side (or from one side if it's a dead-end application where the valve is the terminus of the line). Grooved end & Tri-clamp butterfly valves are also readily available and are designed for use in systems using those end configurations.