A butterfly valve is a valve which can be used for isolating or regulating flow. The closing mechanism takes the form of a disk. Operation is similar to that of a ball valve, which allows for quick shut off. Butterfly valves are generally favored because they are lower in cost to other valve designs as well as being lighter in weight, meaning less support is required. The disc is positioned in the center of the pipe, passing through the disc is a rod connected to an actuator on the outside of the valve. Rotating the actuator turns the disc either parallel or perpendicular to the flow. Unlike a ball valve, the disc is always present within the flow, therefore a pressure drop is always induced in the flow, regardless of valve position.
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. The valve may also be opened incrementally to throttle flow.
There are different kinds of butterfly valves, each adapted for different pressures and different usage. The resilient butterfly valve, which uses the flexibility of rubber, has the lowest pressure rating. The high performance butterfly valve, used in slightly higher-pressure systems, features a slight offset in the way the disc is positioned, which increases the valve's sealing ability and decreases its tendency to wear. The valve best suited for high-pressure systems is the triple offset butterfly valve, which makes use of a metal seat, and is therefore able to withstand a greater amount of pressure.
Read more about Butterfly Valve: Types, Wafer-style Butterfly Valves, Lug-style Butterfly Valve, Images
Other articles related to "valve, butterfly valve":
... Globe valve A valve controlled by a wheel Large butterfly valve Cast iron butterfly valve Cast iron butterfly valve Hastelloy ball valve Stainless steel gate ...
... SFE 4.7 VJGAEA Position mid-engine, rear-wheel drive Configuration longitudinal 60-valve 65° V12, derived from F1 unit Aspiration natural, with variable length intake manifold via ... final drive housing, 3 scavenger pumps Variable intake butterfly valve in carbon fiber intake manifold closed at low rpm, open at high rpm Variable exhaust ...
... the piston descends in the cylinder and the intake valve is open ... of fuel/air mix entering the engine, a simple butterfly valve (the throttle) is generally fitted at the start of the intake manifold (just below the ... The butterfly valve is simply a circular disc fitted on a spindle, fitting inside the pipe work ...
... Cast iron butterfly valve Cast iron butterfly valve Large butterfly valve Large butterfly valve used on a hydroelectric power station water inlet pipe in Japan ...