Zero-leakage pneumatic butterfly valve for gas conveying pipeline

The utility model discloses a zero-leakage pneumatic butterfly valve for a gas conveying pipeline, and belongs to the technical field of gas conveying pipeline equipment. The problems that a valve plate and a valve seat of a common pneumatic butterfly valve are poor in sealing and large in leakage amount are solved. Specifically, a valve seat is arranged between the valve plate and the shell, andthe valve seat is used for preventing the valve plate and the shell from being abraded during relative movement; a sealing groove is formed in the valve seat, an air seal connector is arranged on theshell, the air supply end of the air seal connector is communicated with the sealing groove, and the air seal connector is used for being externally connected with an air supply device so as to inflate the sealing groove. According to the structure, the valve plate and the valve seat of the pneumatic butterfly valve are sealed through sealing gas, a gas sealing ring is formed in a sealing groove of the valve seat, and it i