Lean six sigma application for enhancing production efficiency in plasticizing machines manufacturing: a metalworking industry case study

Introduction This study examines the application of Lean Six Sigma methodology to enhance production efficiency in the manufacturing of plasticizing machines in a metalworking company. Methods The study applied the DMAIC cycle — Define, Measure, Analyze, Improve, and Control — to identify and address critical inefficiencies in the production process. Tools such as Value Stream Mapping, Pareto Charts, 5S, and Poka Yoke were used to diagnose process waste, analyze root causes, and implement improvement actions. Results The implementation of Lean Six Sigma tools led to a 37% reduction in manufacturing lead time, decreasing the process duration from 67 to 42 days. Production capacity increased by 60%, while the financial analysis showed that the proposal was economically feasible, with an Internal Rate of Return of 30.24%. Discussion The findings demonstrate that Lean Six Sigma can provide an effective and low-cost methodological framework for optimizing production processes in metalworking manufacturing contexts. However, the results are specific to the plasticizing machine manufacturing process analyzed, and the short timeframe of the study limits conclusions regarding the long-term sustainability of the improvements.