Development of a new internal finishing process applying magnetic abrasive finishing by use of pole rotation system

An internal finishing process applying Magnetic Abrasive Finishing (MAF) was proposed to produce smooth inner surfaces of tubes at a high rate. Since this process uses the tube rotation system, it has been considered applicable only to tubes which are rotatable at high speeds. Here development of the pole rotation system to extend the scope of the application of the internal finishing process applying MAF was made. By the pole rotation system, the abrasive magnetically attracted by the poles is rotated along the inner surface of the tube by magnetic force together with rotating poles, finishing the inner surface of the tube. Moreover, with the rotating poles being driven in the direction of the tube axis, the abrasive is also driven by following the poles' motion, finishing all of the inner surface of long tubes without rotating the tubes. This paper presents the processing description, the development of finishing equipment and the finishing characteristics. The finishing tube experiments will show the applicability of this new technique for precision internal finishing of long stainless steel tubes used in the conventional clean piping system.