Abstract: The purpose of the present invention is to further level the amount of polishing during electrolytic polishing of the inside of a hollow pipe. A holding frame for vertically holding a hollow pipe is pivotally supported on a rack so as to be vertically invertible about the vertical center of the hollow pipe. An electrode is inserted through the hollow pipe and a liquid buffer is disposed on each end of the hollow pipe. A valve mechanism is capable of switching a liquid supply/discharge circuit so as to supply an electrolyte via the liquid buffer positioned at the bottom and discharge the electrolyte via the liquid buffer positioned at the top whether it is before or after the inversion of the holding frame (inversion of the hollow pipe). During an electrolyte supply period before and after the inversion, an electrolytic treatment is as a matter of course carried out for a predetermined length of time. Although said switching by the valve mechanism may be manually performed, a control means may also be used.

Abstract: A rotor for polishing hollow tubes, in which an outer tube is slidable over an inner tube and is provided with at least one window in the wall. At the window on the inner tube, a plate vane is fixed at the base end to an auxiliary shaft arranged perpendicular to the main shaft so as to be able to rotationally move. A link bar is arranged in the main shaft direction to extend between the outer tube and the plate vane. The rotor is able to transition between an initial state (plate vane closed) and an operational state (plate vane open) by the inner tube moving relative to the outer tube. An electrode for electropolishing or a buff for mechanical polishing is fixed to the tip end of the plate vane. This allows for adjustment of the position of the plate vane and control of the polished state.

Abstract: A wing electrode is configured by disposing at least a wing in a circumferential direction at equal intervals, the wing having a specific width in an axial direction of the electrode shaft and a tip in a shape corresponding to an inner surface of the hollow tube. A housing tube is arranged concentrically to the electrode shaft and to house the wing electrode by winding the respective wings around the electrode shaft. A slit of the housing tube is arranged in the axial direction so as to correspond to each wing. A diameter adjustment unit is operable to expand and contract each wing in the radial direction by rotating the electrode shaft and the housing tube relatively after inserting each wing into the slit of the housing tube. As a matter of course, the electrolyte is filled in the hollow tube at any time before the electrolytic treatment.