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

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International Journal of System Assurance Engineering and Management  vol: 8  issue: S2  first page: 910  year: 2017  
doi: 10.1007/s13198-016-0549-5

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Universitat Politècnica de València

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