Circular Economy Optimization of SMED Changeovers for Energy-Efficient Sustainable Automotive Manufacturing Systems

This study investigates the application of the SMED (Single-Minute Exchange of Die) methodology to improve operational efficiency and support energy- and resource-efficient manufacturing systems. The research is based on a case study conducted in an automotive company producing electrical harnesses, where SMED was implemented to optimize changeover processes and reduce process-related inefficiencies. The methodological approach follows an AS-IS to TO-BE framework, incorporating direct observation, time measurements, and the classification of activities into internal and external operations. In addition to operational indicators, selected energy- and resource-related aspects such as energy consumption during changeovers, material usage, and waste generation were evaluated based on process observation and indirect estimation. The results indicate a significant reduction in changeover time, along with improvements in machine availability and production flow. Furthermore, the study suggests a reduction in process-related energy consumption and material intensity associated with improved organization and reduced downtime, although these effects are partially indirect. The findings demonstrate that SMED can enhance operational efficiency and indicate its potential to improve energy performance in manufacturing systems, primarily through reduced machine downtime and more stable production flows. However, the results are case-specific, and further research based on direct energy measurements and broader industrial applications is required to confirm their generalizability.