Session 6: Thermo-energetic analysis and modelling, shown by the example of spindles

A new calibration approach for a grey-box model for thermal error compensation of a C-Axis
C. Brecher, R. Spierling, M. Fey
Laboratory for Machine Tools and Production Engineering, RWTH Aachen University

Thermal errors cause significant geometrical errors on machined work pieces. This paper presents an approach to calibrate a simplified grey-box model under real workshop conditions, using control internal data as input datas. The calibration is performed with a new measuremnt approach for rotary axis, inspired by ISO 2306 ETVE test. The model leads to an error reduction of a selected th

Investigation of passive torque of oil-air lubricated angular contact ball bearing and its modelling
J. Kekula, M. Sulitka, P. Kolář, J. Shim, P. Kohút
Faculty of Mechanical Engineering FS, Czech Technical University in Prague

Comparison of thermal compensation modelling techniques for high speed motorized spindle
A. Mathur, S. Grama, A. N. Badhe
Dr. Kalam center for innovation, India

Cooling potential of heat pipes and heat exchangers within a machine tool spindle
B. Denkena, B. Bergman, H. Klemme, D. Dahlmann
Institute of Production Engineering and Machine Tools, Leibniz Universität Hannover

Heat losses of the motor and bearings lead to thermal loads on motor spindles and thus to machining inaccuracies, varying dynamic spindle stiffness and decreasing bearing life. The herein introduced novel cooling approach uses heat pipes and heat exchangers to dissipate heat from the shaft through air convection to decrease thermally induced influences on the spindle. This paper illustrates the implementation of the heat transfer devices into a spindle system and results of measurements on a prototype spindle. Finally, the concept’s potential for reducing spindle displacement, system temperatures and the time to reach a thermally stable state is shown.