According to DURET and PILLET (2002), to making products of quality does not issue itself, it results from a step. Not only is it necessary to be able to carry out required quality, but it is necessary to also set up a system making it possible to perennialize what was carried out. This step is induced by a policy quality which depends obviously on the direction and which is put in action within the system of management of quality. This last is described in the handbook quality and has the role of planning, of controlling, of ensuring, of evaluating and of improving quality.
Quality falls under a step of continuous improvement. The latter was proposed by DEMING and is used today in many modes of management (management environment, management of maintenance...). It is materialized by a wheel rolling on a ground going up, so as to raise quality. The engine is the realization of the four stages of the improvement which are:
- plan the improvement,
- follow out what was planned,
- check what was made,
- act on the failing points.
Figure 1 Quality wheel
To work upstream possible, to make the preventive one, it is to satisfy the customer, but also "to earn money". A cost of nonquality treated with the level of the drawing (preliminary draft, project, definition) is 1000 times (even 10000 times) less expensive the company than treated as customers (cost in guarantee, called into question of the means of manufacture, the range, the supplies, the drawings...). Failure modes analysis (FMECA) is one of the invaluable methods which makes it possible the company to validate throughout the construction of a product or a service, its quality and its reliability. FMECA identifies the causes of failures and cures it while bringing the preventive and corrective solutions to answer the satisfaction of the customer fully.