Integrating the Theory of Constraints and Six Sigma in Manufacturing Process Improvement

Authors: Kai Jin, Hyder Abdul-Razzak, Yousri Elkassabgi, Hong Zhou, Aaron Herrera

Abstract:

Six Sigma is a well known discipline that reduces variation using complex statistical tools and the DMAIC model. By integrating Goldratts-s Theory of Constraints, the Five Focusing Points and System Thinking tools, Six Sigma projects can be selected where it can cause more impact in the company. This research defines an integrated model of six sigma and constraint management that shows a step-by-step guide using the original methodologies from each discipline and is evaluated in a case study from the production line of a Automobile engine monoblock V8, resulting in an increase in the line capacity from 18.7 pieces per hour to 22.4 pieces per hour, a reduction of 60% of Work-In-Process and a variation decrease of 0.73%.

Keywords: Constraint Management, Manufacturing Process Improvement, Six Sigma, System Thinking.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1074337

References:

[1] H. Gitlow, and D. Levine, Six Sigma for green belts and champions. Pearson Education Inc. Prentice Hall. Upper Saddle River, New Jersey, 2005.
[2] E. Goldratt and J. Cox , The Goal. North-River Press, Great Barrington, Massachusetts, 2002.
[3] E. Schragenheim, Management Dilemmas: The theory of constraints approach to problem identification and solutions. St. Lucie Press/APICS, Boca Raton, Florida, 2000.
[4] Nave, Dave, "How to compare six sigma, lean and the theory of constraints". Quality Process. American Society of Quality, March 2002, 2002, pp.73-78.
[5] J. Arthur, The Small Business Guerrilla Guide to Six Sigma. Lifestar Publishing. Denver, Colorado, 2003.
[6] M. Gupta, "Activity-based throughput management in a manufacturing company". Int. J. Prod. Res. Taylor and Francis Group, Vol. 39, 2000, pp. 1163-1182.
[7] M. Gupta, "Constraints Management - Recent Advances and Practices". Int. J. Prod. Res. Taylor and Francis Group, Vol. 41, 2003, pp. 647-659.