Reducing manufacturing process variability using experimental design technique: A case study

Experimental design is a powerful technique for understanding a process, studying the impact of potential variables affecting a process and providing spontaneous insight for continuous quality improvement possibilities. It has proved to be very effective for improving the process yield, process performance and reducing process variability. A number of successful applications of the experimental design technique for process optimisation have been reported by both US and European manufacturers over the last ten years. This paper illustrates an application of Taguchi methods (TM) in an industrial setting for identifying the critical factors affecting a certain process and subsequently reducing process variability. Both the analysis of variance (ANOVA) on mean response and the signal-to-noise ratio (SNR) have been carried out for determining the optimal condition of the process. A significant improvement in the process performance was observed in terms of variation reduction.