Design of Distributed Layouts with Operational Efficiency Considerations

The aim of this paper is to approach the design of distributed layouts for lower work-in-process (WIP) levels. Traditionally, the design of manufacturing layouts has considered as objective the minimization of the material handling cost. Alternatively, distributed layouts are claimed to have good performance under volatile environments, though it has been little investigated how these layouts behave in terms of operational measures. In the methodology, a model of the expected transfer time between stations and its variance are derived as a function of the layout. A genetic algorithm is then used to generate distributed layouts through the minimization of the squared coefficient of variation of the transfer times. A simulation study is carried out to validate the results. Finally, the results indicate that reductions in this coefficient of variation, achieved by a proper allocation of machines, may have a beneficial impact on the WIP and, consequently, on the lead time of products.