The butterfly valve is a valve with a circular butterfly plate as the opening and closing part, and the valve stem rotates to open and close to adjust the fluid passage. The butterfly valve disc is installed in the diameter direction of the pipeline. In the cylindrical passage of the butterfly valve body, the disc butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When the rotation reaches 90°, the valve is in a fully open state. The structural characteristics of the butterfly valve .
Butterfly valve has the characteristics of simple structure, small size, light weight, material consumption saving, small installation size, fast switching, 90° reciprocating rotation, small driving torque, etc. It is used to cut off, open and adjust the medium in the pipeline, and has good fluid control. Characteristics and sealing performance. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the resistance when the medium passes through the valve body, so the pressure drop generated by the valve is small, and it has good flow control characteristics. The butterfly valve has two sealing types: elastic seal and metal seal. Resilient sealing valve, the sealing ring can be inlaid on the valve body or attached around the butterfly plate.
Valves with metal seals generally have a longer life than valves with elastic seals, but it is difficult to seal them all. The metal seal can adapt to high working temperature, and the elastic seal has the defect of being limited by temperature.
The butterfly valve is required to be used as a flow control, mainly to select the size and type of the valve correctly. The structure principle of the butterfly valve is particularly 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 cooling water systems of thermal power stations.
Commonly used butterfly valves include clip-on butterfly valves, flanged butterfly valves, and butt-welded butterfly valves. The clip-on butterfly valve uses stud bolts to connect the valve to the flanged butterfly valve between two pipe flanges. The valve has a flange on the valve, and the two ends of the valve flange are connected to the two pipe flanges of the welded butterfly valve. The end face is welded and connected to the pipe.
The streamlined design of the butterfly board reduces the loss of fluid resistance and can be said to be an energy-saving product.