Determining the set-up time in the Just-in-Time system

This work presents a methodology to appreciate the magnitude of the set-up in the Just-in-Time production system. The result is given us a function of the product processing time and the prodcution lot size. For this purpose, some realist hypotheses about the structure of the cost for a typical industry and genetic product are made. The safety stock is assumed to be mull and two situation with respect to the lost size, which is desired to be small, are regarded: in the first situation, the manufacture lot is the minimum-cost lot, and, in the second, the processing lot is the maximum-profitability lot. In the first situation, the set-up time must be smaller than in the second situation, if the lot size is the same. So the paper determines a band of values for the set-up time.