The 3-way ball valve has particular structure and design of appropriative control system.It could be used widely in automatic controll systems and industrial sectors like metallurgy, mining, petroleum, chemical, electricity, light industy, watercraft and so on, matching with pneumatic control system.It is applicable to mixed or split stream project of different substance like fluid, gas or stive.We adopt dynamic balance four sides of seat sealed structure(Y type 3-way ball valve is three sides of seat sealed), this kind of structure make sure the good sealing:the slippery flow passage make the resistance of fluid to be weaker, and make the stream more smooth.The valve could be divided to L type and T type by the new open-back type of flow passage.The flange connection of valve could be designed accordding to the requirement of customer.