Improving the environmental performance of machine-tools: influence of technology and throughput on the electrical energy consumption of a press-brake

Abstract: Machine-tools have been identified as one of the main energy-using products to be analyzed in an Ecodesign perspective, targeting the reduction of their environmental impact. Following this, machine-tool manufacturers are committed to anticipate eminent regulations and are looking for guidelines to improve their products on an effective and low-cost manner. This paper describes part of the energy consumption study followed in the frame of the Ecodesign of a commercial press-brake. All-hydraulic and all-electric commercially available systems, of different capacities and working in real production scenarios, have been included. From this study, a preliminary version of an LCI dataset for the bending process is proposed, structured in technology, machine capacity and usage mode categories, and using the bending cycle as the reference unit. The energy consumption per category was estimated based on a specific process energy model built as a function of the referred parameters. The contribution of the respective machine-tool structure to the environmental impact of the machining process is to be included, targeting the completion of such machining unit process dataset. The full LCA of an all-hydraulic system revealed the significant contribution of the machine-tool structure to the global life-cycle environmental impact of the machine (about 40%), while electricity during use phase contributes with about 46% to the total impact. This contradicts the general results published for other metal and non-metal forming processes, and is understood to be related with the discrete loading character of such forming processes here discussed. [ABSTRACT FROM AUTHOR]