The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. Inside the cylindrical passage of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, with a rotation angle between 0° and 90°. When rotated to 90°, the valve is in the fully open state.
Butterfly valves are simple in structure, small in size, and lightweight, consisting of only a few parts. They can be quickly opened and closed with a simple 90° rotation, making operation easy. Furthermore, these valves exhibit excellent fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is such that the medium flows through the valve body.
The only resistance is pressure drop, resulting in minimal pressure drop and thus excellent flow control characteristics. Butterfly valves are available in two sealing types: resilient seal and metal seal. In resilient seal valves, the sealing ring can be embedded in the valve body or attached to the periphery of the butterfly plate.
Valves with metal seals generally have a longer lifespan than those with resilient seals, but achieving a complete seal is difficult. Metal seals can withstand higher operating temperatures, while resilient seals are limited by temperature.
If a butterfly valve is to be used for flow control, the most important thing is to correctly select the valve size and type. The structural principle of butterfly valves is particularly suitable for manufacturing large-diameter valves. Butterfly valves are widely used not only in general industries such as petroleum, gas, chemical, and water treatment, but also in cooling water systems of thermal power plants.
Commonly used butterfly valves include wafer-type butterfly valves and flanged butterfly valves. Wafer-type butterfly valves are connected between two pipe flanges using double-ended bolts, while flanged butterfly valves have flanges on the valve itself, which are then bolted to the pipe flanges.
