Designing a Stand for Machine Tool Energy Efficiency, With Pump Embodied Energy Tradeoff Case Study

Energy consumption of machine tools needs to be investigated and decomposed to determine areas for improvement. Motors are one key area of energy consumption, and the analysis of motors, including pump motors is useful for long term energy saving. The following paper describes the static and dynamic analysis of a machine tool stand and an energy analysis to compare manufacturing the stand against using the pump motor. The stand needed to be designed that would both withstand the static load of the machine and minimize vibrational excitation caused during grinding experiments. A review of life cycle inventories for induction motors was then undertaken to evaluate the manufacturing energy consumption of pump motors. A breakeven time was determined for the energy investment of replacing a coolant pump with a stand to conserve energy via gravity-fed coolant recirculation. The simulations were performed as worst-case scenarios and are not necessarily indicative of regular use. Results indicate that the stand as designed will not transmit any significant harmonic vibrations. Results of the energy comparison identify that fractional horsepower coolant pumps operating continuously can be replaced with a stand and the energy to produce the stand will break even within two to three years depending on operating schedule.