APPLICATION OF TOTAL QUALITY MANAGEMENT TOOLS USING THE TAGUCHI METHOD ON METAL MANUFACTURING INDUSTRY IN FOUNDRY SHOP. (In case study on Akaki Basic Metal Industry)

Abstract

Casting defects can negatively affect both the quality and quantity of the product in the foundry shop of the metal manufacturing industry. Akaki Basic Metal Industry is one of the metal industries found in Ethiopia producing different metal products. This study aims to identify and minimize current and potential grey cast iron defect which play a significant role in the Company's product quality and profitability. Minimizing casting defect is very important to improve the quality of the products, productivity and also to increase the competitiveness. The Total Quality Management philosophy is the most effective way to reduce the rejection percentage of casting defects from any manufacturing industry. In this study, data was collected through referring recorded documents of the company, semi-structured interviews, and literature review. Based on the collected data major defects were gas porosity, mismatch defect, and slag inclusion, and their root causes were analyzed by using quality control tools such as pareto analysis chart, cause-effect diagram. The most important factors such as pouring temperature, mold permeability, sand binder ratio, and pouring time are optimized according to the Taguchi