The Impact of Applying Lean Six Sigma Tools on Improving the Overall Equipment Effectiveness (OEE) Metric – A Literature Review

Abstract

Abstract In the era of global economic downturn and competitiveness, manufacturing firms face new challenges on a daily basis. One challenge is keeping up with the changes in the surrounding environment, such as those attributed to changes in customer preferences, government regulations, and technology, which leads to fierce competition. In order to stay competitive enough, companies need to not only maintain high performance levels, but also to continuously enhance it. High performance could be achieved and maintained through efforts directed towards reducing production costs, improving efficiency, increasing productivity, and decreasing production losses. Since there typically exists large amounts of losses in manufacturing systems with significant negative impacts, aiming to minimize production losses is critical. Common approaches that would help with decreasing these losses are Total Productive Maintenance (TPM) and Lean Six Sigma (LSS). Of these approaches, LSS have been successfully applied to many manufacturing and service industries. Being the integration of Lean management and Six Sigma approaches, the LSS methodology aims to eliminate the causes of different issues by both reducing overall wastes and minimizing process variations, respectively. With the overarching goal of improving the performance of manufacturing systems, it is important to better understand the impact of using the LSS methodology in reducing production losses within the current industrial environments. To this end, a literature review of the research efforts that included applying the LSS methodology to improve the performance of a manufacturing system, measured through the Overall Equipment Efficiency (OEE) metric, is conducted. This metric is chosen as it is one of the most widely used in the industrial field to quantify the different production losses, by directly summarizing them into one single value. The preformed review is a three-phase systematic literature review that considers relevant publications in leading databases in the field and analyses them to 1) assess the prevalence of related research publications, 2) categorize the different related research efforts, 3) determine the impact of applying LSS methodology on improving OEE, and 4) identify research directions for moving forward in this area. This work focuses also on examining the different LSS tools used and their effectiveness in improving the OEE metric and, in turn, reducing the related losses.