Purpose – This article presents a case of application of the Lean Six Sigma methodology in a powder coatings industrial company. The project had the goal to ensure reproducibility between a quality control step and an extruder machine in order to avoid machine downtime to validate product quality.
Design/methodology/approach – The DMAIC (Define–Measure–Analyse–Improve–Control) approach was followed to increase by approximately 30% the percentage of productions that do not stop for quality control approval and to consequently increase 5 percentage points (pp) of the Overall Equipment Effectiveness. Throughout this five-stage cycle, a set of analytical tools was systematically applied for a correct characterisation of the problem, definition of the input variables and their effect on the response variable, investigation of the cause and effect relationships, selection of the improvements according to their impact and effort, definition of an action plan and continuous evaluation of their effectiveness, culminating in a monitoring and control plan.
Findings – By performing tests throughout the several stages of the process, it was identified that the lack of reproducibility was mainly associated with the incorrect parameterisation and the lack of standardisation. As a result of this project, the percentage of products that do not require the extruder to stop for quality control rose by 40%, with the effect of a 9 pp increase in OEE. The financial return was estimated at 4.8% of the company’s fixed manufacturing costs, in addition to the culture of continuous improvement established in the company. Since this is only the work of a pilot line, the benefits, not only for this project but for others resulting from this new mindset, are expected to be high.
Practical implications – The case study exposes a Lean Six Sigma project carried out in a small and medium-sized Portuguese company, serving as an example of the cross-cutting methodology and the benefits incurred from its use. The respective operational and financial benefits are also presented.
Originality/value – There are very few cases of the application of the Lean Six Sigma methodology in Portugal, applied to small and medium-sized companies. In addition to the fact that they are not reported in the literature, there are no mentioned case studies in this industry: powder coatings. In this sense, this paper, besides being of great importance for similar companies, its application may be generalized to other companies that intend to adopt structured methodologies to improve the quality of their products and the efficiency of their processes.
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Lean Six Sigma, DMAIC, Design of Experiments (DOE), Powder Coatings