Relationships between process batches, transfer batches, and lead times

In this paper, we extend existing batch sizing models by differentiating between process and transfer batches, accounting for material handling, and including group scheduling strategies. The new models are used to capture the tradeoffs that arise from batching decisions and to characterize the optimal transfer and process batches. In particular, we evaluate the effect of smaller transfer batches on part lead times and determine the relationship between the size of the transfer batch and the size of the optimal process batch. We then investigate the impact of material handling delays in a multi-machine system on the optimal size of both types of batches. We also examine the effect of group scheduling rules on the optimal process batch and overall system performance.