Manual butterfly valve is a kind of butterfly valve which is directly operated by handle to realize the opening and closing of the valve, which is widely used in a variety of working conditions and environments, such as water supply and drainage, HVAC, chemical industry, electric power, metallurgy and municipal engineering, etc. It is suitable for water, steam, air, oil and light corrosive media. Suitable for water, steam, air, oil and mildly corrosive media, with good sealing performance and corrosion resistance. Manual butterfly valve has simple and compact structure, light weight, rapid opening and closing, easy operation, small flow resistance, suitable for medium and low pressure piping system. Product advantages include quick installation, easy maintenance, cost-effective, and suitable for flow regulation and cut-off of large-diameter pipelines. The valve is equipped with handle drive, suitable for on-site manual control, support for multi-positioning, to meet the needs of diversified flow regulation. Manual butterfly valve can not only realize the rapid cut-off and connection of the medium, but also effectively regulate the flow of pipeline, it is the ideal choice for safe, reliable and easy operation in industrial and municipal pipeline system.