The Lean System or Lean Manufacturing is completely based on the production system of Toyota (TPS).

Kiichiro Toyoda, Taiichi Ohno, Eijy Toyoda and Shigeo Shingo, implemented a number of innovations in their production lines in a way to facilitate the continuity and the flow of the materials as well as the flexibility, when manufacturing different products. This became more important after the Second World War, when it was necessary to manufacture a wide variety of products in small amounts. This is how the TPS ("Toyota Production System") was created.

The TPS is based on the optimization of the production processes by the identification and elimination of wastes (MUDA in Japanese or WASTE in English) and the analysis of the value chain, to finally achieve a more stable and constant flow of materials, in the correct amount, with an excellent quality and at the time that is needed. This means to have the flexibility and reliability needed to manufacture when the client requires it, no more and no less.

Toyoda came to the conclusion that:

  • Adapting the manufacturing equipment to the real capacity requirements.
  • The introduction of integrated quality systems in the processes (poka-yoke).
  • The equipment arrangement according to the manufacturing sequence.
  • Innovating to have quick model changes so each one of the equipment can manufacture small lots of different pieces.
  • Making every machine notify the previous machine when material is needed. (Pull system).

This will allow the low cost manufacturing with a wide variety of products, high quality and with fast processing time (lead times), to respond in an effective and efficient way to the variations and the clients demands. The management of information is also handled and it is more precise.

Why Lean?

The companies that have applied the Lean Manufacturing tools have had several benefits such as:

  • 50% to 70% increase in productivity.
  • Improvement from 50% to 90% in the reduction of the cycle timing.
  • Improvement from 40% to 90% in quality.
  • Reduction from 50% to 80% in inventory.
  • Reduction from 40% to 80% in waste.
  • Reduction from 50% to 80% in the space assigned for manufacturing and storage.
  • Reduction from 75% to 90% in preparation time.

It is important to mention some of the benefits obtained are usually linked to the area of opportunity detected in the processes; therefore an excellent diagnosis must be made before taking any action of improvement. This is not to create false expectations of the benefits obtained by the use of the Lean tools.