Evaluation of the Energy Consumption of a Directed Lubricoolant Supply with Variable Pressures and Flow Rates in Cutting Processes

Abstract

Despite of considerable improvements in the area of cutting materials and tool coatings, the use of cutting fluid is still essential for the machining of difficult to cut materials like high alloyed steels, titanium or nickel based alloys. However it has to be a major task to set up the application of lubricoolant as effectively as possible. In this context, the high-pressure lubricoolant supply is rendered as a modern technology with a great capability to increase the productivity and process stability in machining difficult to cut materials. In this paper supply pressures up to 300 bar are considered. In terms of sustainable manufacturing it is the aim to minimise the overall energy consumption per part by carefully adjusting and coordinating setting parameters like supply pressure, flow rate, cutting parameters and tool design. In this paper the energy consumption of a machine tool used with a conventional low-pressure flood cooling is compared to the external high-pressure lubricoolant supply. With reference to the applicable cutting parameters depending on the lubricoolant supply strategy and setting parameters, the power consumption, tool wear and chip forms are examined in order to identify the most economical process design. Furthermore the real energy consumption of the lubricoolant supply unit is compared with the theoretically required fluid hydraulic power and an efficiency value is generated. The paper shows that the use of an external high-pressure lubricoolant supply is capable to reduce the overall process energy consumption through a significant increase of the material removal rate while improving the process stability at the same time.