PARTITIONING WORK CENTERS FOR GROUP TECHNOLOGY - ANALYTICAL EXTENSION AND SHOP-LEVEL SIMULATION INVESTIGATION

This paper investigates the effects of partitioning job shop work centers to implement cellular manufacturing. Analytical models are utilized to show that partitioning leads to adverse effects on flow characteristics. The setup reduction introduced in partitioned systems has to overcome these adverse effects before leading to the benefits associated with cellular manufacturing. It is shown that partitioned systems with an insufficient degree of setup reduction are inferior to unpartitioned systems. Two new parameters relevant to this context, the breakeven setup reduction factor and flow ratio, are introduced for the design of viable cellular manufacturing systems. These insights are verified using a shop-level simulation experiment, assuming non-Markovian conditions. The experimental factors include lot size, setup reduction factor, cell size and allowance of inter-cell movements. It is shown that the results are consistent with analytical insights in indicating the range of parameters in which cellular manufacturing may compare favorably with the best of the functional-layout systems.