The main idea of Lean Manufacturing is to increase the efficiency of a process by working smarter, not harder and without increasing the workload. This can be done by eliminating different kinds of wastes (non value adding activities) as will be explained briefly.
This means that a production system produces and delivers the needed amount of products at the right time. When implemented correctly this will reduce overproduction and inventory and thereby the lead time. Also it provides possibilities to add flexibility in handling demand changes.
Elimination of errors is a very cost effective measure. Faulty products are a source of waste, which sometimes can be overcome fairly easily. The design of processes can be improved by introducing poka yokes (Japanese for “mistake proofing”). For instance parts may be designed in a way that they can only be installed by a worker in one possible way, thereby eliminating human errors.
By the introduction of standardized processes and operations we can eliminate variation in process times, operators can be trained more easily and faults are discovered faster. This also provides a base for future improvements.
Kaizen means continuous improvement of a complete value stream or individual processes by adding more value and reducing waste. Improving individual processes can be done by every worker. The improvement of the value stream is a management task. The improvement procedures have to be executed daily and “The idea is to nurture the company’s human resources as much as it is to praise and encourage participation in kaizen activities” (Tozawa, Bunji).
These are only a few examples of the methods concerning lean manufacturing.