SETTING PLANNED LEAD TIMES FOR MULTI-OPERATION JOBS

This paper deals with the problem of how to assign planned lead times for multi-operation jobs. The standpoint of the paper is that planned lead times should be determined, based upon a management policy concer ning a tradeoff between work-in-process quantities in a shop and capac ity requirements variations on a bottleneck machine. A method of deter mining a planned lead time for a multi-operation job is proposed, thro ugh analyzing average loading times in a shop and capacity requirement s variations on a bottleneck machine. The lead time is determined on t he basis of the job's total operation time in a shop. Poisson job airi val to a shop and periodic loading are assumed. The method is derived with Lagrange's method of indeterminate coefficients. It can minimize capacity requirements variations on a bottleneck machine under a given average loading time in a shop.