A proposal for improvement of production processes with lean SWOT analysis and 9S method and an application

Constantly changing conditions such as developing technology, increasing competition, changing customer expectations, high quality requirements, short-term delivery requirements, and decreasing product lifecycles force businesses to reduce production costs and maintain flexibility. In this dynamic environment, it is essential for businesses to develop effective strategies to achieve sustainable competitive advantage. Implementing the lean thinking philosophy in businesses is a key component of these strategies, contributing to the elimination of waste and the establishment of a customer-focused value creation system. In this study, the machining processing area of a manufacturing company operating in the casting industry was selected as a pilot area, and this area was comprehensively improved within the framework of the Lean SWOT Analysis methodology. Lean SWOT Analysis operates like a PDCA cycle, addressing the Strengths, Weaknesses, Opportunities, and Threats dimensions in the process together and managing these four dimensions interactively with a continuous improvement approach. This method transcends the problem-focused, classical problem-solving logic, enabling the further development of strengths and enabling the use of strengths as effective leverage to improve weaknesses. In addition to the lean SWOT approach, the 9S method, implemented for the first time in Turkey, was used in the study. Unlike the 5S and 6S concepts found in the literature, a 9S method was proposed with updated content and sequence, enriched, and successfully implemented in a pilot region. 9S went beyond the S factors known in the literature and was redesigned to address the continuity, employee engagement, and cultural adoption issues frequently encountered in 5S practices. This method ensured the permanent establishment of a lean culture within the company; critical factors such as motivation, ownership, and continuous improvement were integrated into the system, along with order, discipline, and standardization. The application results revealed significant improvements within the company. As a result of the lean SWOT analysis, OEE values increased by an average of 5.4%, strengthening strengths and enabling faster improvement of weaknesses. The lean culture was successfully established within the company, and kaizen and problem- solving cultures were adopted through the voluntary participation of employees. Kaizen projects implemented under the influence of this culture have contributed to significant cost reductions. Furthermore, thanks to 9S efforts, the company has transformed into a more organized, streamlined organization that embraces lean thinking. Thus, both the Lean SWOT Analysis and the updated 9S method have been demonstrated in practice as concrete, applicable, and extensible improvement tools in production processes. All these improvements have increased the company's competitiveness and ensured sustainable production performance. All of these outcomes demonstrate that the proposed methods can contribute to the literature and serve as an exemplary application model in almost every sector. Keywords: Process Improvement, Lean Manufacturing Techniques, Lean SWOT Analysis, 9S