Wise About Six Sigma Part 1: An Overview of Six Sigma

Whether manufacturing plastic bottles for soda or large metal parts for military aircraft, quality of the end product is always top of mind. For many manufacturers, quality means producing products as close to specifications as possible and with little-to-no variation. Such high-quality products aren’t made by chance. For over three decades, manufacturers across industries have used Six Sigma, a statistical process method for making better products, while lowering costs and eliminating waste.
 
In this blog series, I will take a deeper dive into Six Sigma, looking at its methodology, history, implementation across the enterprise, and impact on company culture. To kick things off, let’s review Six Sigma and its principles.
 
Six SigmaWhat is Six Sigma?
Six Sigma is a data-driven approach to eliminating defects in a process with the goal of six standard deviations between the mean/average of a collected quality data set and the nearest specification limit. For instance, if the metal door for a car should have a thickness of between 12.52 and 12.58 inches according to the manufacturer’s specification limits, then the mean should be 12.55 inches. To indicate that the process is achieving six sigma quality, the standard deviation of the door’s thickness should be, at most, 0.005 inches from the mean. Manufacturers can also look at Six Sigma in terms of defects and process performance. The goal would be no more than 3.4 defects per million opportunities.
 
A Five-letter Strategy
One of my main strategies for implementing Six Sigma is the DMAIC approach. It is an acronym that describes five phases for driving process improvement: define, measure, analyze, improve, and control.

  • Define the problem, objectives, project plan, and customer requirements.
  • Measure current process performance, and set in place a data collection plan, process map, metrics, and benchmark for improvement.
  • Analyze the collected data to identify gaps between current performance and the ultimate goal, any sources of variation, and opportunities for improvement.
  • Improve the target process, and fix and prevent any sources of variation using new solutions and technology.
  • Control the improved process and make sure it doesn’t deviate back to the old ways of doing things.
 
Mastering Six Sigma
If you work in manufacturing, then you have likely come across a colleague with “Six Sigma Black Belt” or “Six Sigma Green Belt” on their LinkedIn profile or business card. These individuals have demonstrated a thorough understanding of Six Sigma principles and how they can be applied to achieve process improvement goals. Just like colored belts are presented to signify skill levels in martial arts, professionals can earn certifications or “belts” according to their Six Sigma proficiency.

  • White Belt: Presented to individuals who are aware of basic Six Sigma concepts. They may work within problem-solving teams that support projects, but may not be part of an organization’s Six Sigma project team.
  • Yellow Belt: With an understanding of the process and terminology associated with Six Sigma, these individuals may participate in a Six Sigma project team. Often, they review process improvements that support a project.
  • Green Belt: Professionals pursuing Six Sigma Green Belt certification must have at least three years of experience directly related to process improvement. They must demonstrate an in-depth understanding of Six Sigma tools and processes. They can assist with data collection and analysis for Black Belt projects, as well as lead other Green Belt projects or teams.
  • Black Belt: To achieve Six Sigma Black Belt certification, an individual must complete two Six Sigma projects. These professionals will have mastered the Six Sigma philosophy and principles, and be able to lead teams in process improvement strategies.
  • Master Black Belt: This is the highest and most coveted Six Sigma certification. Individuals must already have Black Belt certification and five years of direct experience or prove completion of 10 Six Sigma projects. They act as an organization’s strategic consultants, as well as mentor Black Belts and Green Belts.
 
InfinityQS has multiple Six Sigma Black Belt executives on staff and Six Sigma Green Belt–certified account managers. In 2017, our application engineering and client solutions engineering teams also became Six Sigma Green Belt certified.
 
Now that we have established a foundation of knowledge, stay tuned for the next installment in our blog series when we trace the history of Six Sigma!

Read more in the Six Sigma series:
Steve Wise
By Steve Wise
Vice President of Statistical Methods
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