Large diameter vacuum butterfly valve
he butterfly valve is installed in the direction of large diameter pipe plate. In the cylindrical channel of butterfly valve body, the disc-shaped butterfly plate rotates around the axis, the rotation angle is between 0 ° and 90 ° and when the rotation reaches 90 ° the valve plate is fully open.
Large diameter butterfly valve, clip type butterfly valve, simple structure, small volume, light weight, only a few parts. Moreover, the valve can be opened and closed quickly by only 90 ° rotation, which is easy to operate. At the same time, the valve has good fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of butterfly plate is the only resistance when the medium flows through the valve body, so the pressure drop generated by the valve is very small, so it has good flow control characteristics. Butterfly valve has elastic seal and metal seal. Elastic sealing valve, sealing ring can be inlaid on the valve body or attached to the periphery of butterfly plate.
The valve with metal seal has longer service life than that with elastic seal, but it is difficult to seal completely. The metal seal can adapt to higher working temperature, while the elastic seal has the limitation of temperature.
If butterfly valve is required to be used as flow control, the main thing is to select the correct size and type of valve. The structure principle of butterfly valve is especially suitable for making large diameter valve. Butterfly valve is not only widely used in petroleum, gas, chemical industry, water treatment and other general industries, but also used in the cooling water system of thermal power station.
There are two kinds of butterfly valves in common use, one is clamp butterfly valve and the other is flange butterfly valve. Clamp type butterfly valve is to connect the valve between two pipe flanges with stud bolts. The flange butterfly valve is a valve with flange, and the flange on both ends of the valve is connected to the pipe flange with bolts.
The butterfly valve adopts the sandwich center plate structure, which is mainly composed of valve body, valve plate, valve shaft, valve seat and transmission device. The structure is simple and compact. With 90 ° opening and closing, the valve can switch and adjust the flow of medium in the pipeline according to different control signals, with small flow loss, clear indication direction, convenient maintenance and long service life.