The butterfly plate of the wafer butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical passage of the valve body of the butterfly valve, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0 ° -90 °. When it is rotated to 90 °, the valve is fully opened. This valve is generally installed horizontally. Wafer type butterfly valve is simple in structure, small in size and light in weight, and consists of only a few parts. And only need to rotate 90 ° to quickly open and close, simple operation, and the valve has good fluid control characteristics. 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. There are two types of butterfly valve: elastic seal and metal seal. Elastic sealing valve, the sealing ring can be embedded on the valve body or attached to the periphery of the butterfly plate.
Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to achieve complete sealing. Metal seals can adapt to higher operating temperatures, while elastic seals have the disadvantage of being limited by temperature.
If the butterfly valve is required to be used as a flow control, the main thing is to choose the valve size and type correctly. The structural principle of the butterfly valve is especially suitable for making large-diameter valves. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also in cooling water systems of thermal power stations.
Commonly used butterfly valves are wafer butterfly valves and flanged butterfly valves. Wafer type butterfly valve is to connect the valve between the two pipeline flanges with double-headed bolts. Flange type butterfly valve is to have a flange on the valve, and use bolts to connect the two ends of the valve to the pipeline flange.
