Papers by Keyword: Internal Magnetic Field Assisted Finishing Process

Abstract: This paper describes an internal finishing process for thick non-ferromagnetic tube (10~20 mm in thickness) by the application of a magnetic field-assisted machining process using a magnetic machining jig (permanent magnet tool). In this study, a new automatic inner surface finishing system was developed, and to achieve smooth surface roughness and high form accuracy, a multiple-stage machining which contains of rough machining and precision finishing was carried out. Especially, in order to improve the form accuracy the rough processing time was made longer compared with the research in the past. The experiments were performed for a thick SUS304 stainless steel tube 10 mm in thickness. The results showed that surface-roughness and form accuracy were able to be improved greatly, the initial surface roughness of 4.9μm Ra can be improved to 0.01 μm Ra and the roundness of inside tube can be improved from 206 μm to13μm.

Abstract: This paper proposes a new magnetic field assisted machining process using a magnetic machining jig (permanent magnet tool) to finish the internal surface of thick tubing 5~30 mm in thickness. Because the magnetic machining jig consists of permanent magnets, it can generate a higher magnetic force (finishing force) than conventional magnetic abrasives, and makes possible the internal finishing of thick non-ferromagnetic tubing. First, the principle and the feature of this process were examined. It was compared that the difference of the mechanism of using the conventional magnetic abrasives and magnetic machining jig (magnet tool) was clarified. Next, a processing unit and magnetic machining jig were made, and the processing unit was set on a lathe machine. An experiment was performed on a thick SUS304 stainless steel tubing 5 mm in thickness. In this study, it was clarified that this processing method can improve the roundness of the inside tubing while improving the surface roughness. The results showed that the initial surface roughness of 6.5 μm Ra can be improved to 0.06 μm Ra, and the roundness of the inside tubing can be improved from 187 μm to 89 μm.

Abstract: This paper examines a new magnetic field assisted machining process using a magnetic machining jig. By using this process, a high efficiency and high quality internal finishing process can be achieved, and it was clarified that it was very effective to finish the internal surface of a thick tube (5~30mm in thickness). In this study, the experiments performed on the SUS304 stainless steel tubes (10mm in thickness) examine the applicability of improving the internal surface roughness and the roundness of inside tube, and it also examine the effects of a rotational speed of the magnetic machining jig. The results showed that this processing method enables improve the internal surface roughness and the roundness of inside tube. It is clarified that the roundness of inside tube is highly dependent on the rotational speed of magnetic machining jig, and the roundness can be improved rapidly at a higher rotational speed with the magnetic machining jig.