The butterfly valve is a butterfly valve that can be opened and closed by rotating the butterfly plate 90° around the fixed axis in the valve body. The butterfly valve is small in size, light in weight, simple in structure, and consists of only a few parts.
It can be opened and closed quickly by rotating 90°, and is easy to operate. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the only resistance when the medium flows through the valve body. Therefore, the pressure drop generated by the valve is very small, so it has good flow control characteristics. Butterfly valves are divided into two types of sealing: elastic soft seal and metal hard seal. For elastic sealing valves, the sealing ring can be embedded in the valve body or attached to the periphery of the butterfly plate.
It has good sealing performance and can be used for throttling, as well as for medium vacuum pipelines and corrosive media. Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to achieve complete sealing. They are usually used in places where flow and pressure drop vary greatly and good throttling performance is required. Metal seals can adapt to higher operating temperatures, while elastic seals have the defect of being limited by temperature.