Title: Defect control analysis for improving quality and productivity: an innovative Six Sigma case study

Authors: M. Shanmugaraja, M. Nataraj, N. Gunasekaran

Addresses: Department of Mechanical Engineering, Government College of Technology, Thadagam Road, Coimbatore – 641013, Tamilnadu, India. ' Department of Mechanical Engineering, Government College of Technology, Thadagam Road, Coimbatore – 641013, Tamilnadu, India. ' Angel College of Engineering and Technology, Angel Nagar, Dharapuram Main, Road, Tirupur – 641 665, Tamilnadu, India

Abstract: This research study proposes an innovative analysis for controlling the defects in aluminium die casting industry. In this analysis, casting process of a two-stroke engine oil pump body is concentrated. The component selected has often rejected due to blow hole defects. Six Sigma, the zero defect approach, is used in this study. Define measure, analyse, improve and control (DMAIC) problem solving methodology is applied for problem analysis. Taguchi|s experimental design is used for process validation and improvement. The confirmation experiment showed that the rejection rate was reduced to 4.8% from 17.22%. The application of Six Sigma program with Taguchi technique has developed an innovative cost effective methodology for controlling defects in die casting process in less experimental time.

Keywords: defects; aluminium die casting; blow holes; productivity; quality; six sigma; define measure analyse improve control; DMAIC; Taguchi methods; experimental design; analysis of variance; ANOVA; signal to noise ratio; S/N ratio; defect control analysis; engine oil pumps.

DOI: 10.1504/IJQI.2011.040428

International Journal of Quality and Innovation, 2011 Vol.1 No.3, pp.259 - 282

Available online: 26 May 2011 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article