Lean Thinking in a Nutshell
The Toyota Production System (TPS) is a production methodology that has become the top waste reduction standard for factories worldwide, and the concept behind it is known today as “lean thinking,” a multi-faceted approach to eliminating waste in every aspect of a company ‘s operation. The focus of lean thinking and production is a united approach that doesn’t just involve top management; it includes the entire workforce.
A Brief History of “Lean Thinking”
While the term “lean thinking” was coined by James P. Womack and Daniel T. Jones in the 1990s during their in-depth study of Toyota ‘s legendary production system, the concepts behind lean thinking actually have a long history. There are documented examples of Benjamin Franklin’s lean thinking in regards to waste in his Poor Richard’s Almanack and The Way to Wealth.
He that idly loses 5s. worth of time, loses 5s., and might as prudently throw 5s. into the river.
(Poor Richards Almanack, 1737)
You call them goods; but, if you do not take care, they will prove evils to some of you. You expect they will be sold cheap, and perhaps they may for less than they cost; but, if you have no occasion for them, they must be dear to you. Remember what Poor Richard says; Buy what thou. hast no need of, and ere long thou shalt sell thy necessaries. . .
(The Way to Wealth, 1758)
Fast forward a couple of hundred years to the American automotive industry and the “world ‘s first systematic lean thinker,” Henry Ford. Ford focused on the value creation process rather than assets or organizations. Ford abhorred waste and emphasized the need to analyze every step in every process to see if it created value; if the step did not create value, Ford felt the step should be eliminated. (Womack, “The Lean Way Forward At Ford.” The Lean Enterprise Institute, www.lean.org.) In My Life and Work (1922), Ford wrote these two short paragraphs that illustrate his concept of waste:
I believe that the average farmer puts to a really useful purpose only about 5% of the energy he expends…. Not only is everything done by hand, but seldom is a thought given to a logical arrangement. A farmer doing his chores will walk up and down a rickety ladder a dozen times. He will carry water for years instead of putting in a few lengths of pipe.
His whole idea, when there is extra work to do, is to hire extra men. He thinks of putting money into improvements as an expense…. It is waste motion – waste effort that makes farm prices high and profits low.”
Ford claimed that Benjamin Franklin was a major influence on his business practices, which included Just-in-time manufacturing.
Toyota and Taiichi Ohno
Now we jump ahead a few years to Japan and Taiichi Ohno, who is considered the father of TPS and Lean Manufacturing. Ohno joined the Toyoda family’s Toyoda Spinning in 1932 and moved to the Toyota motor company in 1943 where he worked as a shop-floor supervisor and gradually rose through the ranks to become an executive. He devised the “Seven Wastes” model (or muda) as part of the Toyota Production System and wrote several books about TPS. Ohno claimed that he learned what to do from reading Henry Ford ‘s books.
Lean Thinking and Waste
Muda is a Japanese word meaning futility; uselessness; wastefulness. In Lean Thinking it is defined as any expense that does not help produce value in the operation. The original seven muda are:
- Transportation (moving products that are not actually required)
- Inventory (all components, work-in-progress, and finished product not being processed)
- Motion (people or equipment moving or walking more than necessary)
- Waiting (waiting for the next production step)
- Overproduction (production ahead of demand)
- Over Processing (due to poor tool or product design)
- Defects (the time and effort involved in inspecting and fixing defects)
In 2003, Womack defined an eighth muda: manufacturing goods or services that do not meet customer demand or specifications. Some other additional wastes added, and universally accepted are:
- Working to the wrong metrics or no metrics at all
- Not utilizing a complete worker (not allowing them to contribute ideas)
- Improper use of computers (not having the proper software, time spent surfing, playing games, etc.)
“5 Whys” Technique Used in Lean Thinking
How does one reduce waste or solve problems? By asking why? -at least 5 times. The 5 Whys is an iterative interrogative technique used to explore the cause-and-effect relationships underlying the problem. Sakichi Toyoda developed the technique in the 1930s and it’s still used today. This simple technique can often direct you quickly to the root or roots of a problem, but the key is to avoid assumptions and logic faults and trace the chain of causality to a root cause. This problem-solving technique uses counter-measures rather than solutions. A counter-measure is an action that seeks to prevent the problem arising again, while a solution may only deal with the symptom. When asking “why” produces no more useful responses, you will have revealed (hopefully) the nature of the root cause and can develop counter-measures that will prevent the problem from recurring.
Lean Thinking is a big topic! We’ll be exploring more in future posts, so stay tuned!
We understand the impact of operational costs on any size business and we are committed to helping our customers increase efficiency and profitability through lower material expenditures and cost efficient design solutions. For more information on how we can help you increase efficiency and profitability, contact us here or call 800-230-8846 now to speak to a warehousing expert.