Butterfly Valves
We offer a full range of butterfly valves in a variety of sizes, pressure ratings and materials; in wafer style, lugged and tapped or fully flanged. The relatively low cost of production in medium to large sizes, and their low weight compared to gate valves makes butterfly valves a popular choice for shut off and throttling.
A butterfly valve is from the family of quarter turn valves. The “butterfly” is a metal disc mounted on a spindle. When the valve is closed, the disc is turned so that it completely blocks off the passageway. When the valve is open, the disc is rotated a quarter turn so that it allows unrestricted passage.
A wide range of body, disc and seat materials are available to cope with most applications, from ambient temperature water to high temperature, high pressure and corrosive products. They can also be designed for vacuum and cryogenic service.
The basic butterfly valve uses an elliptical disc to give a tight shut off; off setting this disc on the spindle gives lower operating torque, lower abrasion of the seat, and tight shut off even with metal seats. The disc may be double or triple offset, and these are known as high performance butterfly valves.
The restricted bore in butterfly valves make them unsuitable for hot tapping, but the disc design means that the valve has a relatively low CV when fully open, giving low pressure drop when compared to say a globe valve. The design lends itself to throttling, and with disc modifications, makes excellent control valves.
Being a quarter turn from fully open to fully closed, and having a low operating torque, butterfly valves can be readily actuated for remote operation.
When selecting a butterfly valve, it is important to consider operating temperature and pressure, media properties, duty required and suitability for the environment
Call now to discuss your requirements.