The evaluation and control of energy efficiency in machine tools are crucial to achieving energy conservation and emission reduction in manufacturing. However, existing energy efficiency models primarily focus either on the energy efficiency of material removal or on the inherent energy efficiency of machine tools themselves, without considering the impact of speed loss caused by low-load operation on the overall energy efficiency of the machining process. To address this gap, this paper establishes a novel load-energy efficiency model for machining systems to specifically assess the impact of speed loss on machining energy efficiency. Furthermore, a statistical process control method for load-energy efficiency is proposed to monitor energy use. Finally, a case study of load-energy efficiency modelling and control for the CK6153i lathe is conducted, demonstrating the effectiveness of the proposed method through a reduction in energy loss of 417.54 kJ and an increase in load-energy efficiency by 4.59%. The proposed method reveals previously untapped opportunities for energy saving in machining processes. The study provides a more nuanced understanding of the relationship between speed loss and machining energy efficiency, thereby offering practical insights for machining energy optimisation.
Jia et al. (Thu,) studied this question.