Lean and Six Sigma are common terms you hear in an industry. But what is lean and Six Sigma, and what do they do?
Six Sigma is a structured, data-driven process of solving critical issues in a process to make it more efficient with the end result of achieving enhanced performance.
How does Six Sigma achieve more from processes?
The common measurement scale in Six Sigma is called the Sigma capability or Z, which is a universal scale. It is a scale such as a yardstick measuring inches or a thermometer measuring temperature.
The scale allows us to compare business processes in terms of the capability to stay within the quality limits established for that process. The Sigma scale measures Defects per Million Opportunities (DPMO). Six Sigma equates to 3.4 defects per million opportunities.
Six Sigma is an integrated part of the improvement process. It is a management methodology driven by data and focuses on projects that produce measurable business results. The central idea behind Six Sigma is that if you can measure how many” defects” you have in a process, you can systematically determine how to eliminate those and get to “zero defects”.
Sigma is a value from 1 to 6 that signifies the maximum number of defects per million:
- 1 Sigma = 690,000 defects/million = 31% accurate
- 2 Sigma = 308,537 defects/million = 69.1463% accurate
- 3 Sigma = 66,807 defects/million = 93.3193% accurate
- 4 Sigma = 6,210 defects/million = 99.3790% accurate
- 5 Sigma = 233 defects/million = 99.9767% accurate
- 6 Sigma = 3.4 defects/million = 99.999997% accurate
- Six Sigma is about reducing variation.
- Six Sigma find out the facts before acting.
Lean means continuously improving processes towards the ideal of achieving the shortest possible cycle time through the tireless reduction of waste. Lean methodology is focused on eliminating wastes in all processes and enhancing the value of for the end customers.
Examples of Lean projects:
- Reduced inventory
- Reduced floor space
- Quicker response times and shorter lead times
- Decreased defects, rework, scrap
- Increased overall productivity
The phrase “lean manufacturing” was coined in the 1980’s and has its roots in the Toyota Production System. Most of the basic goals of lean manufacturing are common sense, and some fundamental thoughts have been traced back to the writings of Benjamin Franklin.
Henry Ford cited Franklin as a major influence on his lean business practices, which included just-in-time manufacturing. The founders of Toyota designed a process with inspiration from Henry Ford and their visits to the United States to observe the assembly line and mass production that had made Ford rich. The process is called the Toyota Production System, and is the fundamental principle of lean manufacturing. Two books have since shaped the ideologies of Lean: “The machine that changed the world” (1990) and “Lean Thinking” (1996).
Training in Lean and Six Sigma involves:
- Building knowledge of process management, Six Sigma and Lean techniques as business process improvement methodologies.
- Developing skills at improving the ease and performance of the processes in which you work.
- Understanding your role as a process team member for the achievement of business success.
- Selecting and improving one of the process you either own or work in.
Using Lean and Six Sigma methodologies, millions of companies around the world have lowered their cost of production while increasing value of their products/services.