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Butterfly valve is a kind of valve to realize opening and closing control by rotating the valve plate, widely used in water supply and drainage, HVAC, chemical industry, electric power, metallurgy, food and pharmaceuticals and other working conditions. It is suitable for water, steam, air, oil and many kinds of corrosive media, with good sealing performance and corrosion resistance. Butterfly valve has compact structure, light weight, rapid opening and closing, easy operation, small flow resistance, and can realize rapid switching and adjustment function. Advantages of the product include low cost, easy installation, simple maintenance, and is suitable for large-diameter piping systems. Butterfly valve can be equipped with manual, pneumatic, electric and other driving methods to meet different automation control needs. Its unique valve plate design enables it to realize both medium cut-off and flow adjustment in pipeline system, which is an ideal choice for modern industrial and municipal pipeline network with high efficiency, economy and reliability.