30s of last century, the United States invented the butterfly, the 1950s brought to Japan, the 60-year generation pneumatic valve was widely used in Japan Fire butterfly, while in China it is a matter of promotion after the 1970s. Operating torque boat with a butterfly, a small installation space and light weight. To DN1000, for example, butterfly about 2T, while the gate of about 3.5T, and the butterfly is easy with a variety of drive combinations, with good durability and reliability. The disadvantage is that when the rubber sealing butterfly valve for throttling, due to improper use will produce cavitation, the rubber seat spalling, damage from happening. For this purpose 80 years -90 years metal. But how to choose the right they should according to working conditions. Butterfly relationship between the opening and flow, basically linearly proportional to the change. If used to control the flow, the flow resistance of the flow characteristics and piping are also closely related to the slow closing valve, such as the installation of two pipelines valve diameter, so the whole form of the same, and the pipe loss coefficient is different, the difference between the flow valve will be great. Many Chinese valve industry chain, but non-valve power. To see the whole country has entered the ranks of the world's great powers valve, but the quality of products from the point of view of the valve power is still very long gap. Production industry concentration, low-end product development capabilities matched valves, valve industry, the low level of manufacturing technology still exists, import and export trade deficit expanded. Can really survive in the market valve business is definitely not there so much. Fire butterfly valve out of Hong Kong, Guangzhou, Hong Kong and butterfly valves provided by the Dongguan Science and Technology Co., Ltd. Ming. Port Valve Co., Ltd., Dongguan Ming (www.gdmgfm.com) is Dongguan, butterfly leaders, over the years, the company implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In the next port of the valve leading the staff warmly welcome all inquiries negotiations to create the next port of the valve a better future.