Variable heat sources in machine tools lead to unsteady displacement fields and hence necessitate temperature control in order to maintain the required positioning accuracy. Adding passive components that redistribute heat through heat storage and heat transport within the machine tool is one approach to compensate for thermal errors. While including latent heat storage components reduces the machine response to heat inputs in a certain temperature range, highly conductive elements like heat pipes provide the option to transport heat losses to environmental air or further components. Thereby, the temperature field around heat emitting machine components can be altered aiming for a reduction of thermal displacements of the tool center point. In order to guarantee the efficacy of corresponding compensation systems in machine tools, the performance of heat pipes under accelerating forces has to be determined. The present paper presents findings of experimental investigations on translationally moved heat pipes conducted on a linear direct drive based test rig. A simulation approach for modeling the heat transfer limits of heat pipes is proposed providing a high compatibility with finite element models. Different scenarios for the use of heat pipes in machine tools are demonstrated and evaluated by means of numerical results.
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