Heating and ventilation pipeline connecting structure

The utility model relates to the technical field of pipeline connection, and discloses a heating and ventilation pipeline connecting structure which comprises a fixing ring, a connecting cylinder is fixedly assembled on the outer edge of the fixing ring, a main lead screw is fixedly assembled on the outer edge of the fixing ring, a main thread ring is connected to the outer edge of the main lead screw in a threaded mode, and a U-shaped ring is fixedly assembled on the outer wall of the main thread ring. An adjusting ring is fixedly assembled in an inner cavity of the U-shaped ring, an auxiliary screw ring is fixedly assembled in the inner cavity of the U-shaped ring, an auxiliary screw rod is in threaded connection with the inner wall of the auxiliary screw ring, and a clamping ring is fixedly assembled on the outer edge of the auxiliary screw rod. According to the heating and ventilation pipeline connecting structure, the clamping ring, the main lead screw and the auxiliary lead screw are arranged on the out