Steel pipe chamfering and polishing machine

The invention discloses a steel pipe chamfering and polishing machine, and belongs to the technical field of steel pipe chamfering and polishing. The steel pipe chamfering and polishing machine comprises a device base, a supporting frame plate is fixedly connected between the two sides of the top of the device base, and a high-precision hydraulic cylinder is installed in the center of the top of the supporting frame plate; the output end of the high-precision hydraulic cylinder is fixedly connected with a driving supporting assembly, the bottom of the driving supporting assembly is fixedly connected with a multi-face connecting block, multiple side faces of the multi-face connecting block are fixedly connected with fixed rotating shafts, and the multiple fixed rotating shafts are rotationally connected with pipe diameter adjusting mechanisms. The pipe diameter adjusting mechanism comprises two connecting hole plates rotationally connected to the fixed rotating shaft, and a U-shaped connecting plate is fixedly