Achieving energy efficient process chains in sheet metal forming

Energy and resource efficiency is a pressing issue for technological markets in the twenty-first century. In the field of production technology, the development of energy and resource efficient processes and process chains occupies a leading position. In order to overcome these challenges, sustainable methods and standards have to be developed. Moreover, the implementation of these methods with the help of a planning tool for professional users is necessary. This paper presents a new procedure for the evaluation of processes and process chains with regard to energy and resource efficiency. The core of the procedure is to balance and to evaluate the existing material and energy flows. Furthermore, the implementation of the balancing models and calculation rules into a user-friendly tool for process chain improvement and design is demonstrated. The procedure is explained and validated using press hardening process chains as an example. The main objectives are to identify the recommended energy efficient process chain from a range of possible process chain variants and to derive proposals for technical improvements. However, the fundamental part for a holistic examination of press hardening process chains is the comprehensive analysis of the present situation. Thus, the individual process elements like raw material, electric energy or forming tools of each process step are systematically identified and classified in a techno-ecological model. Additionally, the cause-effect influences within the process chain are revealed and technological limitations are identified. Based on this information, the material and energy demands of each process are defined by using a factorial analysis, calculations or estimations under selected constraints. The hierarchical structure of the model allows the combination of individual process balances to a process chain balance. Thereby the evaluation of process chains in terms of energy and resource efficiency is possible. As a result, the procedure provides the user with a tool kit, which offers the possibility for a systematically analysis, the detection of improvements and the definition of design parameters.