Process improvement through Six Sigma with Beta correction: a case study of manufacturing company

Abstract

This article discusses the successful implementation of Six Sigma DMAIC (Define–Measure–Analyse–Improve–Control) methodology along with Beta correction technique in an automotive part manufacturing company. The implementation of Six Sigma approach resulted in reduction of process capability-related problems and improved the first pass yield from 94.86 % to 99.48 %. After studying the baseline performance of the process, a brainstorming session was conducted with all stakeholders of the process for identifying the potential causes of the problem. Data were collected on all the identified potential causes and various statistical analyses like regression analysis, hypothesis testing, and Taguchi methods were performed for identifying the root causes. Solutions were identified and implemented for the validated root causes, and results were observed. The Beta correction technique was introduced for monitoring the process in the control phase. Implementation of Six Sigma methodology with Beta correction technique had a significant financial impact on the profitability of the company. An approximate saving of US$87,000 per annum was reported, which is in addition to the customer-facing benefits of improved quality on returns and sales. This study contributes uniquely by elucidating the synergistic impact of Beta correction for greater effectiveness of Six Sigma programmes in the engineering industry.