Product Description
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.Butterfly ValveA 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,[clarification needed] and is therefore
able to withstand a greater amount of pressure.