Lean Manufacturing: Guide


Lean Manufacturing was conceived in the factories Toyota since the 50s and only in the early 90s was studied and codified by US experts Womack and Jones. Despite its high potential for the improvement of production systems there are still countries that do not use the best Lean Manufacturing.

It consists of five basic principles and a set of techniques that allow the application thereof.

In line with the five principles, the objectives of Lean Manufacturing are:

  • identify the activities that generate value for the customer;
  • map the value stream (value stream mapping);
  • minimize waste, ie the non-value added activities (muda);
  • “create the flow” of the activities that generate value;
  • ensure that the flow is “pulled by the customer” (pull);
  • adjust production capacity to demand rhythm (takt time);
  • minimize the setup time (through the SMED technique);
  • break down the production lead time (lead time);
  • Minimization of semi-finished stocks (supermarket and kanban system);
  • introduce process controls and error-proof systems (poka-yoke);
  • implement vision inspection systems (visual management);
  • activate a cycle of continuous improvement (kaizen).

Lean Manufacturing is not intended as a rigid and unique approach, but as an organic set of techniques that are modulated and adapted to the specific operating environment.

Despite the very high potential, Lean Manufacturing (also known as the Toyota Production System) is still relatively limited at Italian companies. In fact, focusing on the reduction of activities that do not add value (waste) tends to question the traditional logic of production “batch and queue” in favor of a production as much as possible “to flow.” The techniques of Lean Manufacturing does not necessarily mean, as incorrectly you can think of, the existence of production lines dedicated to the product families, but can be successfully applied even where there is an organization in specialized departments or islands.