The role of the ball valve is generally used in the pipeline to switch off or adjust the medium, including the three-way ball valve can be flexibly cut off, distribution and change the direction of the flow of the medium. The sealing surface of ball valve is usually in a closed state with the sphere, so it is not easy to be washed away by the medium, convenient operation, simple and compact structure, can be used in water, natural gas, acid, solvent and other conditions.