Ball valve itself is the main characteristics of compact structure, reliable sealing, simple structure, convenient maintenance, sealing surface and the spherical often in the closed state, not easily be medium erosion, easy operation and maintenance, applicable to water, solvent, acid and gas, such as general work medium, but also is suitable for the working conditions of media, such as oxygen, hydrogen peroxide, methane and ethylene, widely used in various fields. The ball valve body may be integral or modular.