Overview:
What Lean Systems Are
Four Main Goals of Lean Systems
History
Time Line
Further Reading
References
External Links
Comments
What Lean Systems Are:
Definition: Lean Systems are inventory and manufacturing management schemes. Lean Systems are customer driven as products are produced only for a specific customer instead of being added to inventory. Instead of allotting resources that would be required for future production, lean manufacturing systems focus on decreasing system response time so that the production system is able to immediately change and adapt to market demands; having what you need on hand when you need it.
The Four Main Goals of Lean Systems:
Improve Quality: Processes to meet/ exceed customer expectations and requirements.
Eliminate Waste: Waste is any activity that consumes time, resources, or space but does not add any value to the product or service.
There are seven types of waste:
1) Overproduction (occurs when production should have stopped)
2) Waiting (periods of inactivity)
3) Transport (unnecessary movement of materials)
4) Extra Processing (rework and reprocessing)
5) Inventory (excess inventory not directly required for current orders)
6) Motion (extra steps taken by employees due to inefficient layout)
7) Defects (do not conform to specifications or expectations)
Reduce Time: Reducing the time it takes to finish an activity from start to finish is one of the most effective ways to eliminate waste and lower costs.
Reduce Total Costs: To minimize cost, a company must produce only to customer demand. Overproduction increases a company’s inventory costs due to storage needs.
History
It has been said that most of the basic goals of lean manufacturing are common sense and documented examples can be seen back as far as writings of Benjamin Franklin’s (left). Franklin’s looking at the cost of wasted time he said that "[h]e that idly loses 5 shillings worth of time, loses 5 shillings and might as prudently throws 5 shillings into the river”. The idea that there was no sense in wasting assets, something had to be developed. This thinking inspired many including the likes of Eli Whitney, Henry Ford and The Toyota Motor Company.
“Eli Whitney(right) is most famous as the inventor of the cotton gin. However, the gin was
a minor accomplishment compared to his perfection of interchangeable parts in 1799”. That was the beginning of taking the primary ideas of the science of lean systems and combining them with manufacturing. For the next 120 years advances in manufacturing were individual successes for each company, not the industry as a whole.
In 1913, the man who really starting developing and implementing the science of lean systems into daily manufacturing tasks was Henry Ford (left). Always being focused on waste reduction, he built these practices into his massive assembly plants. Absolute efficiency always being a goal top of mind to Ford, his way of manufacturing took the world by storm; financially, industrially, and mechanically.
Ford used special-purpose machines to fabricate and assemble vehicle components to create always perfectly fitting components, and have them right at the assembly line for installation within minutes. This was revolutionary compared to the common practices of other vehicle makers. Ford pioneered what he called “flow production", being the first person to integrate an entire production system.
Although no great invention is flawless, one significant flaw in Ford’s production system was the involvement of the customer aspect-failing to incorporate the notion of the "Pull" and thus often suffered from over production.
Post World War II, Kiichiro Toyoda (left), founder of Toyota Motor Corporation, Taichii Ohno and Shigeo Shingo, adapted Ford’s principles as a means of balancing Toyota's then limited human and mechanical capital. They created the Toyota Production System (TPS) which was one of the first managerial systems using lean principles that produced a wide variety of products at lower volumes and had many fewer defects than Ford. The exploding success of Toyota was because they recognized the central role of inventory and used this to their advantage to provide both continuity in process flow and a wide variety in product offerings
Coming forward to today lean systems are heavily used in many manufacturing plants and even in small businesses. See time-line below:
Figure 1 http://www.strategosinc.com/just_in_time.htm
For further information on Lean Systems and the history of Lean Systems see below:
Further Reading
James P. Womack and Daniel T. Jones(1996) Lean Systems
MacInnes, Richard L. (2002) The Lean Enterprise Memory Jogger
James P. Womack, Daniel Roos, Daniel T. Jones (1990) The Machine That Changed the World
James P. Womack, Jeffrey K. Liker (1997) Becoming Lean: Inside Stories of U.S. Manufacturers
References
A Brief History of Lean. (n.d.). Retrieved January 29, 2008, from Lean Enterprise Thinking: http://www.lean.org/WhatsLean/History.cfm
Just In Time, Toyota Production System & Lean Manufacturing. (n.d.). Retrieved January 31, 2008, from Strategos: http://www.strategosinc.com/just_in_time.htm
Lean Systems. (n.d.). Retrieved January 30, 2008, from Wikipedia: http://en.wikipedia.org/wiki/Lean_Systems
Larry Ritzman, Lee Krajewski, Manoj Malhotra, Robert Klassen, 2nd Canadian Edition, Foundations of Operations ManagementExternal Links
British Columbia Institute of Technology
Operations Management 1100 Course Website
Lean Manufacturing Presentations
