Whether gasoline or diesel, engines drive vehicles around the world. Lean and Six Sigma methodologies aid in their manufacture. We’ll look at two applications from India and a master's thesis from Sweden. Then we’ll finish with a video of Cummins diesel engine manufacturing.


Six Sigma Applied to Engine Assembly and Testing: India


In a case study titled “Engine Assembly & Testing Process Quality Improvement Using DMAIC Approach (Six-Sigma)- Case Study,” authors Nitesh M. Kathar,  S. A. Sonawane, and Santosh Badve discuss the application of Six Sigma to reduce defects in the assembly and testing processes.

The case study includes:

  • Project Scope
  • Engine Quality Defect Types and Associated Quantities
  • Indicators from Cause and Effect Matrix
  • Pareto Chart of Engine Quality Defects
  • Cause and Effect Diagram from Oil Leak from Rocker Fulcrum
  • Root Cause Analysis Discussion
  • Results After Implementation of Solutions

As a result of the study, defects were reduced from 17162 PPM to 714 PPM.

You can read the case study here.


Using Six Sigma to Improve the First Pass Yield in Engine Manufacturing: India


In a paper titled “Six Sigma Methodologies for Increasing the First Pass Rate of Engines in Manufacturing,” authors P. Pathmanaban and others discuss using Six Sigma methodologies to increase the first pass rate in engine manufacturing.

The article includes:

  • Gage R&R Report
  • Cause and Effect Diagram for Loss of Power
  • Pareto Analysis of Defects
  • Rejecting Testing Results

As a result of the Six Sigma application, first pass yield associated with tolerance-related problems increased from 95% to over 99%

You can read the paper here.


Improving Material Handling Through the Application of Lean Six Sigma: Sweden


In a master’s thesis titled “Utilizing Lean Six Sigma to Improve Material Handling Operations in the Production of Heavy-Duty Engines at Volvo Powertrain: A Six Sigma Black Belt Project,” authors Majeed Assaf and Patrik Jukic discuss the application of Lean Six Sigma to improve material handling.

The thesis includes:

  • Problem Description
  • Problem Mapping and Project Scoping
  • Process Mapping
  • Waste and Ergonomic Measurements
  • Waste and Ergonomic Analyses
  • Pilot Projects Discussion
  • Productivity and Process Improvement
  • Improvement Monitoring
  • Lessons Learned

You can access the master's thesis here.


Video of Diesel Engine Manufacturing


Visit Cummins Diesel Engine Factory in this video from Cars BOOM.


You can watch the video here.



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