Finishing equipment for finishing inner diameter of motor shell

The utility model discloses finishing equipment for finishing the inner diameter of a motor casing, which comprises an upper module and a lower module, the upper module and the lower module are respectively arranged on a sliding block and a platform of a press machine, the upper module comprises an extrusion assembly connecting plate and an extrusion assembly, the extrusion assembly is detachably arranged on the extrusion assembly connecting plate through a connecting device, and the extrusion assembly is detachably arranged on the extrusion assembly connecting plate. The lower module comprises a bottom plate, an outer cavity fixing ring, a cavity and a material returning mechanism, the cavity and the material returning mechanism are provided with through holes allowing the extrusion assembly to stretch into and penetrate through, the cavity is placed on the material returning mechanism, the cavity is sleeved with the outer cavity fixing ring, the outer cavity fixing ring is connected with the material return