Set management: minimizing synchronization delays of prefabricated parts before assembly

The paper addresses the problem of synchronizing prefabricated parts for assembly into modules. We examine production environments arising out of semiconductor manufacturing and multi layer ceramics where several prefabricated parts, so-called sets, are necessary to complete a module. Frequently, some of these components are manufactured by the same production system. In order to minimize the inventory of the entire production system and simultaneously to achieve short cycle times, we propose sophisticated sequencing rules (named set management policies) to control the production of components. Based on global status information on the inventory at each service station these policies determine the component which is to be processed next. We evaluate the performance of the set management policies proposed, by means of simulation results for several production environments which feature rework and re-entrant flow. In terms of several performance measures we show that our sequencing rules achieve better results than standard rules such as FCFS of EDD. The mean of the performance measures and also their variances are considered