Defect Reduction using Six Sigma Tools in Small Scale Mechanical Manufacturing Company: A Case Study

Six Sigma is a structured methodology that helps organizations solve problems and achieve their goals by reducing defects and variation. This study applies the Six Sigma approach in a mechanical production engineering industry. Using the DMAIC cycle (Define, Measure, Analyze, Improve, and Control), the work systematically identifies the root causes of defects and develops reliable solutions to reduce or eliminate them. Moreover, the Multi-vari analysis and poka-yoke tools were used successfully in this study. Multi-vari analysis was used to find out effect of different process parameters on bore size variation and determine optimum parameters while poka-yoke tool was used to reduce tool resetting error in depth variation problem. After implementing the optimized process parameters, the defect of bore size variation was eliminated and after changing the process to machine both surfaces in one tool setting the depth variation problem vanished. Therefore, applying Six Sigma tools provides an effective approach to reducing defects, lowering costs, and enhancing customer satisfaction.