History of Lean Manufacturing

Defining an age for lean manufacturing is like saying which came first the chicken or the egg, after all at which point in the evolution of the chicken was it a chicken? Lean has roots that go back many years, long before Toyota, some would argue that lean began with Ford's production line to produce the Model T, but things continue to go back further. So what is the history of lean manufacturing ?

The earliest atempt that I can find reference to for the formation of a production line goes back to the early 1800s when Maudsley and Marc Brunel (the father of Isambard) created a production line in the UK to produce pulleys for the Royal Navy, maybe this could be considered the start of lean? There are many things that have contributed to lean as we know it today and things are still being invented and added now, lean is a journey, one that has continually moving destination.

Pareto 's work was published towards the end of the 19th Century, defining the 80:20 rule, a rule that helps us define priorities for much of what we do in improvement projects, typically 80% of our profit will come from 20% of our products, etc. Taylor began his work also towards the end of this century defining his ideas of "scientific management" or work study.

At the start of the 20th Century, Cadillac began to use interchangeable parts in their production, swiftly followed by Ford's introduction of the model T in 1908. Motion studies were defined in 1909 by Frank Gilbreth, his wife Lillian adding a view on the psychology of work motivation.

The famous Ford production line started in 1913.. Toyota looms not starting until 1922 using technology from the UK, and Toyota cars appearing in 1927.

During world war 2 flow production was introduced between Boeing and Ford to produce bombers.

After world war2, things began to change very quickly at Toyota in Japan, in my mind this is where the Lean really began to be defined, Taichii Ohno and Shigeo Shingo inspired by the works of Ford and influenced by the teachings of Shewhart, Deming and Juran began to truly develop the Toyota Production System (TPS) that was to become Lean Manufacturing

Lean Manufacturing as we know it now has developed out of the Toyota Production System (TPS) but What is lean manufacturing , It is both a philosophy and a collection of well proven tools.

Taichii Ohno realised that the biggest threat to their manufacturing was the waste of inventory through overproduction, producing product that was not yet needed or in too great a quantity. Toyota after world war2 was much like any other japanese manufacturer, they had very limited resources, to commit to using these resources to anything other than what the customer wanted today was to risk not being able to supply and thrive as a business. Toyota also wanted to not be as good as the western car manufacturers, they wanted to be better, far better.

This lack of resource coupled with the recognition that inventory and overproduction was waste led to just in time manufacturing (JIT), the principle of making what the customer wants, when the customer wants it, without allowing it to be delayed or caught up in inventory.

Toyota realised that the ideas of Taylor and Ford had many shortcommings when it came to the people within the company, they vary much put a seperation between the management, the thinking few, and the muscle, the workforce! Toyota realised that they had to be able to depend on their workforce, unlike Ford where the workforce was desperate for employment at the time and would put up with poor conditions and low wages therefore depended on Ford! Toyota had to implement respect for its workforce.

The teachings of Deming, Shewhart and Juran were incorporated, creating qualitty circles, involving all within the company with the aim of continual improvement of every aspect of the business.

Other tools began to develop to help with these main aims, JIT, Respect and Continual Improvement, Single Minute Exchange of Die (SMED) was developed by Shigeo Shingo to enable batch sizes to be reduced through the reduction of set up times on machines from many hours down to just minutes and seconds, the set up times causing batches to be too large through trying to maximise utilisation of machine time. Kanban systems were developed to enable flow at the pull of the customer. Kaizen developed to drive continual improvement through constant small projects run by the employees themselves.

In the late 1970s early 1980s many industries (especially the automotive industry) began to recognise that Japanese manufacturers once seen as being mass producers of cheap unreliable products were begining to dominate the markets with higher quality, and less expensive products. High quality in both features offered to the consumer and in the reliablity of the products, this is still the case today!

Many western companies tried to discover what it was that was leading to the successes of these Japanese companies and many visited them, bringing back various ideas and techniques that they had seen. These ideas were copied in the west with little success as they were not being implemented as part of the overall system, trying to implement Kanban without fully understanding the principles of Just in Time is a waste of time.

Many new systems began to appear, "World Class Manufacturing", "Stockless Production", "Continuous Flow Manufacturing" and so on, they were all atempts at trying to copy the Toyota Production System.

Lean Manufacturing itself was "born" through the publication of "The Machine that Changed the World" by Womack and Jones, a detailed comparrison between the Japanese and Western automotive industries. This is where the term Lean Manufacturing was coined.

Since then many many books have been published on lean manufacturing and the Toyota Production System, many companies have tried to implement the philosophys and tools, some successfully and others not so.

Lean as I have already said is not a destination, it is a journey, one that will never be completed as the goal is continually moving. But the philosophy behind lean will be sound for many years to come;
Define value as percieved by the customer, make the value stream flow from raw materials to the customer at the pull of the customer whilst striving to achieve perfection.

Some have tried to suggest alternatives to lean such as Six Sigma, but is it really an alternative? In my mind six sigma is another tool within lean manufacturing, it is about reducing variation to reduce waste, it complements the philosophy of lean totaly. Hence the term used by some trying to combine the two of Lean Sigma. It is not a choice, you do not have to be Lean or six sigma, use both.

Agile manufacturing has been suggested as an alternative to lean, but this is just a "re-branding" of lean focused on industries that need to focus on their speed and flexibility as part of the value expected by their customers. You cannot be agile without being lean, the only reason for the rebranding is to overcome the poor perception of lean cause by failed initiatives that have focused purely on waste reduction thus removing the flexibility and ability to react from those companies.

Lean is Fast, Flexible Flow, Lean is focus on customer value, Lean is Flow, Lean is continual improvement, Lean is what you need to implement if you want to succeed in your business.