Lean Manufacturing Vs. Traditional Manufacturing

For years manufacturers have created products in anticipation of having a market for them. Operations have traditionally been driven by sales forecasts and firms tended to stockpile inventories in case they were needed. A key difference in Lean Manufacturing is that it is based on the concept that production can and should be driven by real customer demand. Instead of producing what you hope to sell, Lean Manufacturing can produce what your customer wants...with shorter lead times. Instead of pushing product to market, it's pulled there through a system that's set up to quickly respond to customer demand. So this is the major difference that one can see with the traditional and lean manufacturing...



There is an overall change in the Organizational characteristics and the Manufacturing methods, which is shown in the table below....

	TRADITIONAL MASS PRODUCTION	LEAN PRODUCTON
Production schedules are based on…	Forecast — product is pushed through the facility	Customer Order — product is pulled through the facility
Products manufactured to…	Replenish finished goods inventory	Fill customer orders (immediate shipments)
Production cycle times are…	Weeks/months	Hours/days
Manufacturing lot size quantities are…	Large, with large batches moving between operations; product is sent ahead of each operation	Small, and based on one-piece flow between operations
Plant and equipment layout is…	By department function	By product flow, using cells or lines for product families
Quality is assured…	Through lot sampling	100% at the production source
Workers are typically assigned…	One person per machine	With one person handling several machines
Worker empowerment is…	Low — little input into how operation is performed	High — has responsibility for identifying and implementing improvements
Inventory levels are…	High — large warehouse of finished goods, and central storeroom for in-process staging	Low — small amounts between operations, ship often
Inventory turns are…	Low — 6-9 turns pr year or less	High — 20+ turns per year
Flexibility in changing manufacturing schedules is…	Low — difficult to handle and adjust to	High — easy to adjust to and implement
Manufacturing costs are…	Rising and difficult to control	Stable/decreasing and under control