Talk about the function of butterfly valve.The name of the butterfly valve comes from the shape of its butterfly plate, which is a winglike structure, like the wings of a butterfly.The valve body of the butterfly valve is cylindrical, and the disk-shaped butterfly plate rotates around the centerline of the valve shaft to open and close the valve. The angle of rotation is between 0-90°. When the butterfly valve is closed at 0° and the butterfly valve is opened at 90°, the function of the butterfly valve is to cut off and connect the medium flow in the pipeline. Between 0-90°, the function of the butterfly valve can be used as a regulating valve to control the flow of medium in the pipeline.
As a widely used valve, the function of the butterfly valve is mainly to cut off or regulate the flow of media in the production line. Butterfly valves are widely used in production lines in general industries such as water conservancy projects, water treatment, petroleum, chemical engineering, and urban heating. They can also be used in condensers and cooling water systems of thermal power stations.
The butterfly valve can be divided into a midline butterfly valve and an eccentric butterfly valve according to the structural form. The seal of the middle line butterfly valve is usually made of elastic sealing materials such as rubber and fluorine plastics; the seal of the eccentric butterfly valve usually uses metal to metal, metal-to-fluoroplastic and multi-layer composite plates. The elastic sealed butterfly valve is also called soft sealing butterfly valve. Besides its sealing ring, it can be embedded in the channel of the valve body and can be set around the butterfly plate. When a soft seal butterfly valve is used as a shut-off valve, its sealing performance can reach Class VI of FCI70-2:2006 (ASME B16 · 104), which is much higher than that of a metal-sealed butterfly valve. However, due to the limited temperature of the elastic seal material, the soft seal butterfly valve is more often used in normal temperature water and water treatment fields. The metal hard seal butterfly valve can adapt to higher working temperature, and its service life is longer than that of the soft seal butterfly valve. However, the metal seal butterfly valve is difficult to completely seal, and the sealing performance is very poor, so it is generally used for adjusting the flow rate.
The function of the butterfly valve is also manifested in its wide application in the field of large-diameter adjustment, because when the butterfly valve is fully open, the flow resistance is small. When the butterfly plate opening angle is between about 15-70, the butterfly valve can be very sensitive. Control media flow. In addition, since the butterfly plate of the butterfly valve has the wiping property when it performs a rotary motion, the butterfly valve is used in the pipeline with suspended particulate media, and can also be used for powdery and granular media according to the strength of the seal in the pipeline.