Butterfly valve development history
Butterfly valve development history In the 1930s, the United States invented the butterfly valve. It was introduced to Japan in the 1950s and was widely used in Japan in the 1960s. In China, it was promoted in the 1970s. At present, butterfly valves in the world generally have been replaced by DN300 mm butterfly valves. Compared with the gate valve, the butterfly valve has a short opening and closing time, a small operation, a small installation space and a light weight. Taking DN1000 as an example, the butterfly valve is about 2T, and 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. 
Chongqing
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The disadvantage of the rubber sealing butterfly valve is that when it is used for throttling, cavitation may occur due to improper use, and the rubber seat may be peeled off and damaged. To this end, the metal sealing butterfly valve has been developed internationally, and the cavitation zone has been reduced. In recent years, China has also developed a metal sealing butterfly valve. In recent years, a cam-shaped butterfly valve resistant to cavitation, low vibration and low noise has been developed in Japan. 
Generally, the life of the sealing seat is under normal conditions, rubber is 15-20 years, and metal is 80-90 years. However, how to choose correctly depends on the requirements of the working conditions.