Towards an adapted lean system - a push-pull manufacturing strategy

International audience ; he direct transplantation or imitation of lean production has led to difficulties of applying a number of lean principles and practices. Thus, diffusion of one of the main lean principles, just-in-time production, which refers to producing only 'what is really needed, when it is needed, and in the amount needed', seems to be limited. To date, some of the companies produce more than their customers really need. This method of production enables them not only to amortise the high-changeover costs over a large number of products, but also to benefit from commercial opportunities. However, these companies are exposed to financial losses related to storage costs and risks of non-sale. To provide decision elements for determining the best production strategy, we have developed a model for calculating the optimal quantity to be produced. Moreover, we suggest using a fuzzy aggregation system to optimise the consideration of the risk of non-sale. This new approach defines the limits not to exceed by taking into consideration the drawbacks linked to the risks of non-sale.