Formal DEVS modelling and simulation of a flow-shop relocation method without interrupting the production

This paper presents an organizational method of transfer of a flow-shop to a new site without interrupting the production. This method, which can be used even in case of requirements during the removal period, consists in segmenting the flow-shop removal into successive removals of groups of machines. This method can be successfully applied provided a prime condition is met: there must be sufficient stock upstream of the different groups of machines. The role of these stocks is to ensure continuity of production operations between the old and the new site, while a non-operational group of machines is being removed. The removal of groups of machines goes on until the whole production line is transferred to the new site and operational on this site. To validate this approach, we used a simulation and developed a flow-shop model according to the DEVS formalism. Our model makes it possible to segment a production line. We can therefore simulate a sequential transfer of groups of machines to the new site. The most effective solutions among those proposed suggest starting with the final group of machines (finished products) to finish with the first group. In this paper, we present and discuss some simulation results for an industrial case study. These results demonstrate the compared effectiveness of different removal strategies, and help decide for the appropriate estimated project management.