Route selection and flow control in a multi-stage manufacturing system with heterogeneous machines within stages

With increasing market competition and the need to serve diverse market segments, many companies are responding to customer needs by manufacturing parts in small batches. Unless properly planned, batch production can lead to high material handling time. In this paper, a methodology for selecting the best routeing for a batch in a multi-stage production system with material handling considerations is presented. Each stage consists of multiple, functionally identical machines that have non-identical characteristics. The model determines the optimal routeing for the batch and generates the number of parts to handle or transport at a time as a unit load between machines in order to minimize total batch manufacturing time. The result from the model provides the optimal routeing (i.e., the machine to use at each production stage) and the number of parts to move at a time as a sub-lot. The solution procedure developed is easy to use and can be incorporated as a daily shop management tool.