Execution Models for Developing DMAIC Process Using Process Capability Indices  
Author Kuen-Suan Chen


Co-Author(s) Chin Chia Liu; Chi-Han Chen


Abstract The six-sigma method and the process capability index are both commonly used tools in industrial community. Process engineers can follow five improvement steps of the sixsigma method, including “Define”, “Measure”, “Analyze”, “Improve”, and “Control”, to improve and enhance the process quality. However, none of these five improvement steps have a clear corresponding approach. This paper considered the process capability index a process quality evaluation tool widely used in the industrial community as well as a process quality evaluation and analysis tool adopted by internal engineers. Therefore, this paper applied the method integrating process capability index and statistical testing to develop execution models for the five improvement steps, DMAIC, of the six-sigma method. Firstly, this paper, based on the concept of yield, not only deduced the relationship between the required value of the product process capability index and the process capability index value of individual quality characteristic but also discussed the definition of the six-sigma quality level and its relationship with the process capability index. Next, according to these results, five improvement execution models of the six-sigma method were developed and provided to the process engineers in the industry for reference, so as to promote the performance of the six-sigma project.


Keywords quality characteristic, six-sigma method, DMAIC process, process capability indices, six-sigma quality level
    Article #:  RQD27-52

Proceedings of 27th ISSAT International Conference on Reliability & Quality in Design
Virtual Event

August 4-6, 2022