Integrated Optimization of Building and Curing in Tires Production

We address the problem of optimally planning the two main phases in tires production, namely building and curing. They are executed by different machines subject to specific constraints; furthermore, the buffer capacity between the two phases is limited. We present a mathematical model of the optimization problem, that turns out to be a computationally difficult MILP problem. Computational tests show that reducing the symmetries by variable aggregation allows to solve large size instances arising in a real production plant to near-optimality within a reasonable amount of computing time.