Improving the manufacturing process quality and capability using experimental design: a case study

Experimental design is essentially a strategy of planning, designing, conducting and analysing experiments so that valid and reliable conclusions can be drawn in the most effective manner. Experimental design has proved to be very effective for improving the process performance, process capability and reducing rework and replacement costs due to excessive process variability. The paper highlights common problems and gaps in the state-of-the-art in experimental design. The paper also presents a case study performed in a UK firm on a laser welding process for optimizing the product life using experimental design methodology. A significant improvement in the product life was observed. The result of the case study reveals the stimulus for the wider application of experimental design techniques by engineers within the company to achieve process improvement at low costs. Computer softwares such as Minitab and Design-Ease were used for analysing the experimental results.