Reduction in Repair rate of Welding Processes by Determination & Controlling of Critical KPIVs

Faheem Yousaf, Dr. Shahid Ikramullah Butt


Six Sigma is being Implemented all over the World as a successful Quality Improvement Methodology. Many Companies are now days are using Six Sigma as an Approach towards zero defects. This article provides a practical case study regarding the implementation of Six Sigma Project in a Welding Facility and discusses the Statistical Analysis performed for bringing the welding processes in the desired sigma Limits.

DMAIC was chosen as potential Six Sigma methodology with the help of findings of this Methodology, Six Sigma Team First Identified the critical Factors affecting the Process Yield and then certain Improvement Measures were taken to improve the Capability of Individual welding Processes and also of Overall Welding Facility.   Cost of Quality was also measured to Validate the Improvement results achieved after Conducting the Six Sigma Project.


Statistical Process Control (SQC); Process Capability Indices; Six Sigma; Variable control chart; Pareto charts; Standard deviation; Critical to Quality (CTQ); Analysis of Variance (ANOVA); DMAIC; Total quality Management

Full Text:



Chen, K.S., Huang, M.L., Li, R.K. (2001). Process capability analysis for an entire product. International Journal of Production Research, 39(17), 4077-4087.

De Mast, J., Roes, K.C.B, Does, R.J.M.M. (2001). The multi-vary chart: A systematic approach. Quality Engineering, 13(3), 437-447.

Douglas, C.M. (2003). Introduction to Statistical Quality Control. New York, NY: John Wiley Publications.

Flaig, J.J. (2006). Selecting Optimal Specification Limits. Quality Technology & Quantitative Management, 3(2), 207-216.

Flaig, J.J. (2009). A unifying process capability metric. Journal of Industrial Engineering and Management, 2(1), 48-59.

Jacobson, J.M., Johnson, M.J. (2006). Lean and Six Sigma: Not for Amateurs. LabMedicine 37(4):140-145.

Laureani, A., Antony, J., Douglas, A. (2010). Lean six sigma in a call center: a case study. International Journal of Productivity and Performance Management, 59(8), 757-768.

Mahesh, B.P., Prabhuswamy, M.S. (2010a). Improvement of Quality Awareness using Six Sigma methodology for achieving higher CMMI Level. International journal of advance research in management, 1(1), 20-41.

Mahesh, B.P., Prabhuswamy, M.S. (2010b). Process Variability Reduction through Statistical Process Control for Quality Improvement. International Journal for Quality research, 4(3), 193-203.Plecko, A., Vujica, H.N., Polajnar, A. (2009). An Application of six sigma in manufacturing company. Advances in Production Engineering and Management, 4, 243-254.

Ricardo, C., Allen, T. T. (2003). An alternative desirability function for achieving 'six sigma' quality. Quality and Reliability Engineering, 19 (3), 227-240.

Linn, R.J., Tsung, F., Ellis, L.W.C. (2006). Supplier Selection Based on Process Capability and Price Analysis. Quality Engineering, 18(2), 123-129.

Sivasamya, R., Santhakumaranb, A., Subramanianc, C. (2000). Control chart for Markov-Dependent Sample Size. Quality Engineering, 12(4), 593-601.

Abstract Views

Metrics Loading ...

Metrics powered by PLOS ALM


Cited-By (articles included in Crossref)

This journal is a Crossref Cited-by Linking member. This list shows the references that citing the article automatically, if there are. For more information about the system please visit Crossref site

1. Root cause analysis and reliability improvement methods for orbital TIG welding process for propulsion feed system of satellites
M. Karthikeyan, V. N. A. Naikan, R. Narayan
International Journal of System Assurance Engineering and Management  vol: 8  issue: S2  first page: 910  year: 2017  
doi: 10.1007/s13198-016-0549-5

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

Universitat Politècnica de València

e-ISSN: 2340-4876     ISSN: 2340-5317