| High stress concentration happens on both sides of the rollers, also the inner and outer raceway generating lines, due to the elastic deformation and the plastic deformation of the rollers, when cylindrical roller bearing and tapered roller bearing are in a state of being loaded. The stress concentration mentioned above often leads to further development of fatigue collapse and breakingoff toward to the core. Which could make the entire bearing fail. This plays an important role in the decaying of the bearing life and the rotation precision.The stress distribution of rolling contact zone could be effectively improved if the bearing raceway is changed into arc generating line instead of straight generating line. It will not only reduce the roller edge stress concentration to a large degree even eliminate it ,but also favour the liquid lubrication,also improve the decentre load of roller led by nonconcentricity, result in fixing and processing mismachining tolerance, and the deflection, result in chief axis rotating, It has been proved in many experiments that the life of bearing could be increased to 2~3 times as before by using outer raceway with crown. At present, in most developed countries when designing production of cylindrical and tapered roller bearing, crown is often required. It is also required to many export productions in China. Hence, provides with important theoretical significance and application value to investigate a simple and convenient technique in processing bearing raceway crown deeply.At present, the dominant method in processing bearing raceway crown is to mill the theoretically required crown curve line out in sharpener, with forming grinding wheel or with axises of workpiece and grinding wheel in a special degree, then enhance the surface quality in direction of datum line by superfinish. But usually the raceway crown degree of end item is 5~10μm (sometimes less than 3μm), which is hardly controlled in crown grinding. In addition, obligating superfinish process redundancy will make precise crown controlling even more difficult.By reference of the successful application of electrochemical gear trimming and definitude of research aim that ensuring bearing raceway crown and surface quality, theory and technique in electrochemical abrasive belt grinding (ECABG) bearing raceway trimming is put forward an investigated systematically in this paper. That had established a base of forming a simple and easily controlled technique in processing bearing raceway crown, Here is the major work:1)C620 engine lathe has been changed and an appropriate experimentequipment has been set up, including the processing electric source, recycle system of electrolyte, tool cathode and the rotative sets of abrasive belt;2) The finite element method(FEM) was applied to solve the inverse boundary problem of tool cathode in the electric field by MATLAB programming, which can provide one method for computer aided cathode design in ECM;3)The influence of technologic parameters, such as electric current density, processed time, granularity of abrasive belt, gap between cathode and anode, workpiece' rotate speed, has been researched primarily by orthogonal experiment., which provide the foundation for optimization of technologic parameters. Besides, the feasibility of the bearing raceway crown ECABG is validated through experiments;4)Corrosive and antiseptic experiments using GCrl5 bearing ring has been carried out to determine the economical and suited corrosion inhibitor of electrolyte.Research results show that the bearing raceway crown electrochemical abrasive belt grinding (ECABG) method is feasible, it can not only meet the requirement of trimming crown quantity but also enhance the surface quality of bearing raceway. At the same time, this simple method is easy to handle. All advantages above guarantee a favorable application prospect of it.
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