Cooling system optimization of five-axis machine tool rotary table for improved thermal accuracy and energy efficiency

Thermal errors induced by inefficient cooling in rotary tables of five-axis machine tools significantly degrade machining accuracy and increase energy consumption, posing a critical challenge for high-precision and sustainable manufacturing. This study presents an integrated cooling system optimization framework for five-axis machine tool rotary tables, combining ISO 230-3:2020-based experimental measurements with multi-physics thermal–fluid–structural coupling analysis to accurately characterize heat generation and thermal deformation. Cooling channel geometry, operating parameters, and cooling loop configurations are systematically optimized using the Taguchi method and response surface methodology to achieve both thermal accuracy improvement and energy efficiency. The results demonstrate that the optimized cooling design and operating conditions reduce rotary table thermal errors by more than 12% while simultaneously lowering coolant flow demand, power consumption, and associated carbon emissions by approximately 10%. The proposed approach provides a practical and effective solution for enhancing thermal stability, machining accuracy, and energy efficiency in advanced CNC and five-axis machine tools used in aerospace, automotive, and high-value precision manufacturing applications.