EFFECT OF THERMAL LOAD ON SPECIFIC ENERGY CONSUMPTION IN HEAVY-DUTY CUTTING

Energy efficiency is an important issue in recent manufacturing. Previous studies reported that specific energy consumption (SEC) improves with a higher material removal rate (MRR). However, they did not consider the effect of cooling energy required during machining. This study presents a method to calculate the SEC that considers the heat generated by the machining loads by combining the SEC that is measured by short-time experiments without considering the heat generation and that considering the output characteristics of the cooling system obtained by the preliminary experiments. The calculated results were applied to analyze the effect of cooling on SEC in heavy-duty cutting. The results indicate that the cooling energy does not affect the power-law model much in the case of the investigated machine, while a slight difference is observed in the high MRR range. Even at an MRR of 100,000 mm3/min, the difference in SEC with and without considering cooling energy is less than 10%. However, differences may not be negligible in older machines with low efficiency.