Balancing and Sequencing Versus Only Balancing in Mixed Model U-Line Assembly Systems: an Economic Analysis

Abstract. With the growth in customers demand diversication, mixed-model U-lines (MMUL) have acquired increasing importance in the area of assembly systems. There are generally two different approaches in the literature for balancing such systems. Some re- searchers believe that since the types of models can be very diverse, a balancing approach without simultaneously sequencing of models will not yield an optimum conguration. On the other hand, another group of researchers point to the high cost of balancing systems and prefer to do it only one time regardless of the models sequences.In this paper, we aim to compare these two approaches by introducing an economic indicator. To do so, two models as representatives of the two different viewpoints are taken from the literature. To check the validity of this methodology, it is implemented by Lingo 11.0, for small scale, and GA, for a large scale. The obtained results indicate that, from the proposed economic indicator point of view, mixed-model U-lines balancing and sequencing (MMUL/BS) is preferred to its coun- terpart, mixed-model U-lines balancing (MMULB).This paper offers economic guidelines for managers to choose between only balancing and implementing it by sequencing at the same time.