Butterfly butterfly plate installed on the pipeline diameter direction. In butterfly valve body cylindrical channel inside, disc butterfly plate around the axis rotation, rotation Angle for 0 ° ~ 90 ° to 90 °, between rotating, the valve is fully open position brand.
Butterfly valve simple structure, small volume, light weight, only by a few parts. And it can rotate 90 ° rapid opening and closing, simple operation, and at the same time, the valve has good fluid flow control characteristics. Butterfly valve in the fully open position, the butterfly plate thickness is medium flows through the body, so the only resistance through the valves produced by the pressure drop is small, it has good flow control characteristics. Butterfly valves have elastic seal and metal seal two seal type. Elastic seal valve, sealing ring can be set in the body or attached to the butterfly plate peripheral.
The metal sealing valve general than elastic seal valve life is long, but it is difficult to be totally sealed. Metal seal can adapt high working temperature, elastic seal has limited by the temperature of the defect.
If required butterfly valve as flow control use, main is to choose the right size and type of the valve. Butterfly valve structure theory is especially suitable for making large diameter valve. Butterfly valve not only in the oil, gas, chemical industry, water treatment and other general industry widely used, but also used in the cooling water system of thermal power plants.
Commonly used butterfly valve have wafer butterfly valve and butterfly valve flange type two kinds. This valve is the valve with stud bolt connection in two pipe flanges and flanged butterfly valve is a valve with flange, bolts on the valve flange connection on both ends of the pipe flange.
 

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