Butterfly valve, opening and closing parts of a disc-shaped disc in the valve body around its own axis of rotation, so as to achieve the opening and closing or regulating valve called the butterfly valve. Butterfly valve fully open to fully closed is usually less than 900, butterfly valves and butterfly rod itself is not self-locking strongly on the stem to the positioning of the disc, install worm gear reducer. Worm gear reducer, not only can make the disc capable of self-locking, stop in any position, but also to improve the operational performance of the valve disc. Characteristics of industrial butterfly valves to high temperature, the applicable pressure range is also high, the valve nominal diameter, the body uses carbon steel, the valve plate seal with a metal ring instead of the rubber ring. Large-scale high-temperature butterfly valve with welded steel plate manufacturing, mainly for medium heat, smoke duct and gas pipelines. 
 Advantages of butterfly valves 
 Open and close easily and quickly, effort, fluid resistance, you can always operating. Simple structure, small size and light weight. Can carry the mud to a minimum accumulation of liquid in the pipe outlet. Under low pressure, can achieve a good seal. Regulated performance. 
 Shortcomings of the butterfly valve 
 (1) the use of pressure and temperature range. (2) poor sealing. Butterfly valve structure can be divided into the offset plate, vertical plate, swash plate and leveraged. According to the sealing form can be divided into the relatively closed-type and two hard seal. Soft seal commonly used rubber ring seal and hard seal type commonly used metal ring seal. Connection type can be divided into a flange connection and the transmission mode can be divided into manual gear, pneumatic, hydraulic and electrical several clip-on connection; 
 Butterfly valve Category 
 Form of the structure can be divided into the offset plate, vertical plate, swash plate and leveraged. According to the sealing form can be divided into the relatively closed-type and two hard seal. Soft seal commonly used rubber ring seal and hard seal type commonly used metal ring seal. Connection type can be divided into a flange connection and the transmission mode can be divided into manual gear, pneumatic, hydraulic and electrical several clip-on connection; 
 Nominal pressure: PN0.5-10.0Mpa 
 Operating Temperature: -40-900 ° C 
 Nominal diameter: DN50-2000mm 
 Connection: clip, flange, butt 
 Material: 304,316,304 L, 316L, SS316, WCB, CF3, CF8, 310S cast steel, cast iron, ductile iron, forged steel, aluminum, stainless steel, copper, etc.