Fluorine-lined three-way reversing ball valve is composed of angular piston pneumatic actuator and three-way ball valve. It is a kind of rotary cut-off and regulating valve. It has the advantages of close, compact structure, light weight and convenient maintenance. High temperature moulding lining fluoroplastics technology is used for inner wall and components of valve body in contact with fluid, and a layer of anti-corrosion materials such as polyperfluoroethylene propylene (F46), polytetrafluoroethylene (PTFE), soluble polytetrafluoroethylene dilute (PFA) is coated, which can completely cut off the contact between corrosive medium and outer shell of valve, so the sealing performance is good. The valve can be operated with valve positioner input control signal (4-20mADC or 1-5V DC) air source. It can also be operated with travel limit switch, solenoid valve, pressure relief valve and 0.4-0.7MPa air source. Two pairs of passive contact signals are sent to indicate the switch of the valve. Two-seat sealed three-way reversing ball valve has compact structure, beautiful appearance and good sealing performance. It can switch the flow direction of medium in pipeline, and can also make two vertical channels connected or closed. Four-seat sealed three-way reversing ball valve has beautiful appearance, compact and reasonable structure. It can not only switch the direction of medium flow, but also make three channels connected with each other. At present, it can also close any channel, make the other two channels connected, and flexibly control the confluence or diversion of medium in the pipeline. It is widely used in the control of strong corrosive medium such as acid and alkali, and gas and liquid medium such as poisonous, volatile and permeable.