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Статья. Опубликована в журнале "International Journal of Innovation, Management and Technology". – 2013. – Vol. 4, No.1 – P. 130-136.
Статья на английском языке.Название на русском языке: Сокращение простоев на ремонт для конических роликовых подшипников за счет магнитно-абразивной финишной обработки (МАО).Аннотация к статье на английском языке:Bearings are one of the most important and critical component in the wide variety of machines. Most of the bearings are failed before completing their theoretical life due to the wear, corrosion, contamination, fatigue etc. The cost and time involved in repairing the bearings is very high. In the present work, Magnetic abrasive finishing (MAF) process is developed to reduce the turnaround time of repairing the taper roller bearing. The finishing time varies according to the level of damage of the bearing surface. The surface of the bearing has complex configuration (curved and conical) thus MAF is best suited due to the self-adaptability of the flexible magnetic abrasive brush (FMAB).Permanent magnets are used to hold the FMAB. The experiments performed using the magnetic abrasive powder (MAP) consisting of abrasives (boron carbide (B4C) and diamond), iron powder, de-ionized water and glycerin in appropriate composition. The aim of the present study is to evaluate the impact of vol. % of diamond abrasives, number of magnets and strength of magnets in nano-finishing of taper roller bearings. The experiments were designed as two level full factorial. The basic principle of material removal is three body abrasive wear. It was found that addition of diamond abrasives in the MAP greatly improved not only the finishing rate but % change in surface finish also. The best finish achieved is (Ra=) 36.5 nm from initial (Ra=) 271.5 nm without any surface damage within 24 min. It is concluded that by implementing the present process a highly finished surface of taper roller bearing can be achieved within a short time span depending upon the initial condition of the bearing surface.
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International Journal of Innovation, Management and Technology, Vol. 4, No. 1, February 2013 Reducing Downtime of Repairing for Taper Roller Bearing by Magnetic Abrasive Finishing (MAF) Process Pawan Kumar Basera and Vijay Kumar Jain attracted by the magnets attached to the tool and forms a flexible magnetic abrasive brush (FMAB). In the FMAB many small abrasive particles acts as a tool. When FMAB is mildly pressed against the surface to be finished and a relative motion is imparted the abrasive particles wear out the material in the form of very small chips [2]. Shinmura et al. [2] explored basic principle of MAF process. They used different sizes of diamond coated cast iron balls to finish the fine ceramic bars and concluded that as the size of diamond abrasive increases the material removal rate increases. Samuels et al. [3] investigated the effect and type of diamond abrasives on material removal rates in polishing of annealed brass. They found that the maximum material removal rate is obtained with a 2-4 µm abrasive grade. They recommended polycrystalline diamond over mono crystalline for higher material removal on hard materials (hardness more than 50 HV). The effect of amount of lubrication used in MAP is studied and it is found that an optimum amount of lubricant affects the abrasive contact against the surface to be finished and results in better surface finish and form accuracy [4]. The antifriction bearing are generally made of steel (AISI 52100) and Mulik et al. [5] conducted experiments on this material having hardness value of 61 HRC and achieved surface roughness of the order of 51nm within 120s. They concluded that mesh size of abrasive and rpm of electromagnet are significant process parameters.