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The piston flow control valve is a speed regulating and pressure regulating valve developed according to the hydrodynamic characteristics. It has been widely used in power station, water diversion, water supply and other fields. The improved series of flow control valves are not only suitable for clean water, but also have good tolerance for natural rivers, lakes and mild sewage. From the design structure and material selection, the problems of scaling, jamming and large driving device of flow control valve for many years have been solved.