Metal pipeline inner wall polishing device

The invention discloses a metal pipeline inner wall polishing device, and relates to the field of metal processing. The metal pipeline inner wall polishing device comprises a bottom plate, a moving assembly is arranged at the top end of the bottom plate, a supporting plate is arranged at the top end of the moving assembly, an electric push rod is mounted in the supporting plate, a plurality sets of arc-shaped clamping plates are arranged on the inner side of the supporting plate, a polishing assembly is arranged on one side of the top end of the bottom plate, and an adjusting assembly is arranged on the inner side of the polishing assembly. Through the arranged adjusting assembly, the polishing assembly can be axially stretched or shortened, and therefore the polishing assembly can be suitable for polishing metal pipelines of different sizes; and through the arrangement of the arc-shaped clamping plates, elastic pads, the electric push rod and auxiliary telescopic rods, the electric push rods can drive the mu