In daily production there are 7 wastes that need to be treat well in order to achieve maximum profit and high productivity. In Lean manufacturing or Toyota Production System the 7 wastes are:
4.Inventory - over stock (unnessary stock),
5.Too many motion,
6.Over processing and,
7.Defective parts or unit also known as rejection.
In order to reduce or eliminate the waste a 7 principles was developed by Toyota known as the 7 principles of Toyota Production System.
1. Reduce setup times.
All setup process that are implemented are a waste because of they tie up to labor and equipment. By organizing procedures, using carts and highly skill workers to do their own setup (self management), Toyota managed to reduce setup times.
2. Small Lot Production:
Producing products in a big lots result in a high setup cost, high capital cost of high speed machinery, larger inventories, long lead time, and of course large defect cost.
3. Employee Involvement:
Toyota organized their workers by forming teams and gave them the responsibility and training to do many specialized tasks. Teams are also given responsibility for housekeeping and minor equipment repair. Each team has a leader who also works as one of them on the line.
4. Top Quality control:
Quality is well control at each station of production line. The concept not to pass defective product to next process which control by the owner(operator) of that process has help a lot of Toyota production line. Any defective product found must be discovered and corrected as soon as possible and therefore to achieve the objective responsibility is given to the owner of that process. If it cannot be fixed, he can stop the line by pulling stop cord called Jidoka.
5. Equipment Maintenance:
One of the major contributors to line stoppage and defective is come from failed equipment. Therefore beside Maintenance people maintaining the equipment, Toyota operator are also assigned for basic maintenance task such cleaning and lubricating. Most important is that the operator is in the best position to detect any abnormality of the equipment. This known as a Total Productive Maintenance.
6. Pull Production.
To reduce inventory holding costs and lead times, Toyota developed the pull production method wherein the quantity of work performed at each stage of the process is dictated solely by demand for materials from the immediate next stage. The Kanban scheme coordinates the flow of small containers of materials between stages. This is a commonly known as Just-In-Time (JIT).
7. Supplier Involvement.
Supplier or vendors is a partner to Toyota. In Toyota Production System supplier shall involve and train together to achieve target for both side.