Control Charts and Pareto Analysis in Enhancement of Product Quality in Shop Floor Manufacturing

Abstract

Aluminium and its alloy find applications in many industrial manufacturing industries, and their importance can always be addressed. Lightness, durability, and corrosion resistance are properties of this engineering material, which enhance its comprehensive utilization in various industries. The working of these materials should be related to product quality and reliability. Therefore, this study investigated the application of control charts and Pareto analysis to minimize product defects in an aluminium company. The production data from 2016 to 2019 was obtained from the aluminium industry in Obio/Akpo. The collected samples were analyzed through control charts and variance analysis. Results showed that of the manufactured products, the highest number of defective occurred in 2018, while the least occurred in 2019. P-chart and C-chart reveal points out of statistical control in 2016, 2017, 2018, and 2019. Pareto analysis showed that 10% of the defects occurred on the fifth day of manufacturing. 9% occurred on the twenty-third day in 2017, while 11% of defectives happened on the eleventh day in 2019. Pareto results also showed that 25% of the total defective products are subjected to severe checks yearly for optimum improvement. Results from the variance analysis showed that material thickness has no significant effect on the number of faulty items experienced per production batch. The C-chart is more effective for quality control analysis than the P-chart. The company advises using C-hart and Pareto charts as control measures to enhance quality production.