Friction-free opening and closing pneumatic ball valve with dust removal function

The utility model relates to the technical field of ball valves, and discloses a friction-free opening and closing pneumatic ball valve with a dust removal function, which comprises a valve body, a valve cover, a valve seat, a ball body, a valve rod and a pneumatic device, a spring is arranged between a radial outer step of the back of the valve seat and a radial inner step of a valve body channel to form a floating valve seat, and an annular arc groove is arranged in the middle of a sealing surface of the valve seat. The valve seat sealing face is divided into an outer annular sealing face and an inner annular sealing face through the annular arc groove, and the annular arc groove is communicated with an air source inlet of the pneumatic device through air holes in the valve seat and the valve body and a pressure guiding pipe, so that the pressure cavity and the pneumatic device supply air synchronously. Air source pressure synchronously enters the annular pressure cavity to compress the spring, the valve se