In cylindrical traverse grinding of a slender workpiece, elastic deformation of the workpiece due to the normal grinding force negatively affect the shape error of the ground workpiece. To prevent the effect of elastic deformation on shape error, a steady rest is generally used. However, the proper usage of a steady rest requires a great deal of skill. Therefore, we propose an advanced grinding method to improve the shape accuracy of the ground workpiece without using a steady rest. In the proposed method, the traverse speed of the grinding wheel is adjusted to keep the elastic deformation of the workpiece constant. Prior to grinding experiments, the relation between the normal grinding force and traverse speed was measured under several grinding conditions. From the obtained relation, the traverse speed that can keep the elastic deformation of the workpiece constant was determined. The shape error of a slender workpiece was improved using the proposed grinding method.

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This paper presents that grinding wheel sharpness can be improved by increasing the peripheral speed of the small-diameter grinding wheel from 9.4ms^-1 to 18.8ms^-1.The following results were obtained. (1)By optimizing the truing depth of cut, micro cutting edges are formed by transferring accurately the sharp corner end of the PCD truer. (2)Smooth chip generation realizes improvement of ground surface and decrease of grinding force. (3)Due to reduction of elastic deformation and ploughing action on ground surface, spark-out number after rough and finishing grinding can be reduced from 10 times to once. (4)Even if the oscillation speed in grinding is raised by 3-folds, the average roughness of finished surface keeps less than 0.2μm. (5)By reducing spark-out number and increasing oscillation speed, total grinding time can be reduced by about 95%, thus high-efficient internal-grinding of small hole is achieved.

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