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

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%.

Authors:

• Kai Jin
• Hyder Abdul-Razzak
• Yousri Elkassabgi
• Hong Zhou
• Aaron Herrera

Keywords:

• Constraint Management
• Manufacturing Process Improvement
• Six Sigma
• System Thinking.

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