The design of mechanizations : reliability, efficiency and flexibility

In this report, we study the efficiency and flexibility of a new mechanization in terms of its dependence on internal factors such as process reliability, as well as external factors such as a flow production environment and the product diversity. In particular, we show why a high process reliability does not necessarily lead to efficient mechanizations. It is demonstrated that, under equal process-reliability conditions, the selection of several small mechanized production units (instead of one large, fast mechanization) significantly contributes to overall system efficiency, as well as system flexibili ty. This becomes crucial in cases where a large product variety requires small batch sizes, as is the case in many consumer product divisions today. In addition, we show that the installation of small strategic buffers between consecutive processes is an effective and efficient way to cope with realistic process uncertainties, while still work-in-process inventory is kept on a reasonable low level. The operational costs resulting from such a design choice may be negligable when compared to the costs needed to further improve process reliability itself.