Butterfly valves regulate or isolate the flow of a liquid medium by means of a rotatable disk. They are characterized by their quick operation.
Butterfly valves regulate or isolate the flow of a liquid medium by means of a rotatable disk. As a quarter-turn valve, fully opening or closing the valve is achieved by rotating the disk a quarter of a turn.
Similar to ball valves, butterfly valves are characterized by their quick and easy operation. They are popular due to their light weight, small installation footprint, lower costs and availability in very large sizes.
Butterfly valves are used where space is limited. Unlike gate valves, butterfly valves can be used for throttling or regulating flow as well as in the full open and fully closed position. The pressure loss through a butterfly valve is small in comparison with the gate valve.
The construction of a Butterfly valve body varies. A commonly used design is the wafer type that fits between two flanges. Another type, the lug wafer design, is held in place between two flanges by bolts that join the two flanges and pass through holes in the valve's outer casing. Butterfly valves are even available with flanged, threaded and butt welding ends, but they are not often applied.
Butterfly valves have a wide range of applications, particularly in flow shut-off, and are used in a variety of process media and industries, especially in LNG, oil, gas as well as water supply, collection and distribution, and pumping stations.