Development of intelligent cylindrical grinding system considering thermal deformation of workpiece

In cylindrical grinding, thermal deformation of a ground workpiece can reduce the size accuracy. To improve the size accuracy, it is necessary to consider the thermal deformation during grinding process. In this study, we develop an intelligent grinding system that can consider the thermal deformation of the ground workpiece. In this system the thermal deformation of the workpiece is simulated during grinding process. The thermal deformation is simulated from the measured grinding force. Grinding force is measured by the strain gauges mounted on the race center. The grinding heat conducted into the ground workpiece is estimated from the measured normal grinding force. The net stock removal, that is the stock removal measured after the workpiece is cooled, is estimated by adding the measured stock removal and simulated thermal deformation of the workpiece. To obtain the target stock removal, the grinding wheel is retracted as the net stock removal is reached to the target stock removal. With using the developed grinding system, grinding experiments were carried out. In these grinding experiments, the size error is reduced less than 1 micro meter in radius even though the thermal deformation is more than 2 micro meters in radius. With grinding experiments, it is confirmed that the developed grinding system can improve the size accuracy successfully.