The commonly used butterfly valve has two kinds of sandwich butterfly valve and flange butterfly valve.Clamping butterfly valve is a double-headed bolt to connect the valve between two pipe flanges, flange butterfly valve is the valve with a flange, bolt the valve on both ends of the flange connection in the pipeline flange.
Butterfly valve disc installed in the pipe diameter direction.In the butterfly valve body cylindrical channel, disc shaped disc around the axis of rotation, rotation Angle between 0°~90°, rotation to 90°, the valve is fully open.
Butterfly valve simple structure, small volume, light weight, only a few parts composed.Moreover, the valve can be opened and closed quickly by rotating only 90°, which is easy to operate. Meanwhile, the valve has good fluid control characteristics.Butterfly valve in the fully open position, butterfly plate thickness is a single resistance when the medium through the valve body, so the pressure drop produced by the valve is small, it has a better flow control characteristics.Butterfly valve has two types of seal seal and metal seal.Elastic seal valve, seal ring can be embedded in the body or attached to the disc periphery.
Valve with metal seal is generally longer than the elastic seal valve life, but it is difficult to achieve complete sealing.The metal seal can adapt to the higher working temperature, the elastic seal has the limitation of temperature.
If butterfly valves are required for flow control, it is important to select the correct size and type of valve.The structure principle of butterfly valve is especially suitable for making large diameter valves.Butterfly valves are not only widely used in petroleum, gas, chemical, water treatment and other general industries, but also in the cooling water system of thermal power plants.
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