Improving the shape quality of bearing rings in soft turning by using a Fast Tool Servo

Björn L. T. Beekhuis, Ekkard Brinksmeier, Martin Garbrecht, Jens Sölter
2009 Production Engineering  
In machining of ring shaped components, the workpiece is deformed by the clamping forces of the chuck. This elastic deformation generates shape deviations in soft turning. Moreover, the machining process generates locally varying residual stresses which contribute to shape deviation of the workpiece. Hence, in machining of thinwalled bearing rings hexagonal out-of-roundness up to 200 lm occur. In order to minimize the shape deviations, a long stroke Fast Tool Servo (FTS) for controlling the
more » ... h of cut was developed. The applied FTS differs from other published FTS systems in the guidance design. The moving tool holder is suspended to the FTS frame by flexure joints instead of using a linear guidance. The flexure joints provide a low stiffness in moving direction and high stiffness in orthogonal directions. The high stiffness in cutting force direction is essential for a real time reduction of shape deviations in soft turning. In this paper, results of an experimental investigation for the reduction of the shape deviation by adapted non circular machining are presented, using the developed FTS. Based on the results, the influence of the cutting forces on part accuracy is discussed.
doi:10.1007/s11740-009-0175-z fatcat:spckzy5bijgjhbr5ycovui3kqi