Thermal network modeling and analysis of bi-directional sliding guide system for CNC machine tools

The thermal stability of bi-directional sliding guide systems directly impacts the machining accuracy and operational reliability of CNC machine tools. However, existing research remains insufficient in modeling their thermal behavior under multi-heat-source coupling and complex contact conditions. To enhance thermal stability during machining, this paper proposes a more comprehensive fully-coupled thermal network model for bi-directional sliding guide systems based on thermal network analysis. This model captures key heat sources and heat transfer pathways within the system, comprehensively describing thermal conduction and feedback relationships. Experimental validation confirms the model’s ability to accurately predict temperature distributions and thermal deformation patterns under various operating conditions. Further analysis reveals that motor speed, lead screw length, and contact interface parameters significantly influence the system’s thermal response. Among these, lead screw length and rotational speed are key determinants of thermal deformation, while lubricant viscosity has a relatively minor effect. This study not only validates the importance of real-time heat source updating mechanisms in reflecting transient thermal behavior but also uncovers the influence patterns of multiple parameters on the thermal performance of guide systems. These findings provide theoretical support and methodological references for thermal error modeling and structural optimization of sliding guide systems in CNC machine tools.