The main objective of this paper is to identify various causes of occurrence of blowholes and recommend corresponding remedies to counter these defects by systematic implementation of DMAIC cycle. | Reduction of rejection of cylinder blocks in a casting unit A six sigma DMAIC perspective Journal of Project Management 4 2019 81 96 Contents lists available at GrowingScience Journal of Project Management homepage Reduction of rejection of cylinder blocks in a casting unit A six sigma DMAIC perspective Surjit Kumar Gandhi Anish Sachdeva and Ajay Gupta Dr. B. R. Ambedkar National Institute of Technology Jalandhar-144 011 Punjab India CHRONICLE ABSTRACT Article history Six-Sigma approach is a systematic and scientific operations management methodology Received October 2 2018 aimed at achieving major enhancements in production process through the elimination of Received in revised format No- waste. In this case a casting unit manufacturing cylinder blocks has been selected which vember 19 2018 was experiencing a rejection rate as high as 30 due to formation of blowholes other than Accepted January 7 2019 Available online the surface. The main objective of this paper is to identify various causes of occurrence of January 7 2019 blowholes and recommend corresponding remedies to counter these defects by systematic Keywords implementation of DMAIC cycle. Both preventive and corrective actions have been recom- Six sigma mended to reduce the blowholes and overall improvement is validated through two-propor- DMAIC tion test. Results of investigation demonstrated the net significant reduction of blowholes Preventive and corrective ac- defect from 28 111 to 9 708 parts per million which results in the net annual savings of INR tions 12 56 640. Rejection rate 2019 by the authors licensee Growing Science Canada. 1. Introduction If an existing process is not meeting customer specifications use of five-phase Six Sigma method- ology also called DMAIC process can be made for better effectiveness and efficiency of production process which ultimately leads to achieve higher productivity. These 5 phases are Define In this phase the problem is explicitly .
