In the 1930s, the United States invented the butterfly valve, which was introduced to Japan in the 1950s and was not commonly used in Japan until the 1960s. However, promotion in our country was after the 1970s. At present, butterfly valves of DN300 mm or above have gradually replaced gate valves in the world. Butterfly valve compared with the gate opening and closing time is short, the operating torque is small, small installation space and light weight. Take DN1000 as an example, the butterfly valve is about 2T, while the gate valve is about 3.5T, and the butterfly valve is easy to combine with various driving devices, and has good durability and reliability.
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