Work-in-Process Evaluation in Job-Shop and Flexible Manufacturing Systems: Modelling and Empirical Testing

Abstract

The authors investigate how work-in-process can be reduced when passing from a job-shop to a flexible manufacturing system. As explained in the paper, the problem can be brought back to analyzing how lead time can be shortened. Lead time evaluation formulas for a job-shop and a flexible manufacturing system are therefore proposed. In the case of job-shop systems the formula is empirically tested by comparing estimated values with data collected in a manufacturing firm. Thus, by comparing the relations proposed, the factors concurring to reduce work-in-process when passing from a job-shop to a flexible manufacturing system are identified: the different ways of processing in the two systems and the possibility of reducing lot size.