On the Determination of the Period Length in a Period Batch Control System

Period Batch Control (PBC) is a production planning system that has strongly been propagated as a simple and effective instrument in obtaining the benefits of Group Technology, such as short throughput times and low work in progress. In order to obtain these benefits, PBC decomposes the manufacturing system in N stages and gives each stage the same amount of time P to complete the required operations. At the end of a period with length P the work is transferred to the next stage, and new work arrives from the preceding stage. One of the problems faced with when designing a PBC system is that there is little support from literature in the selection of a suitable period length for the stages. In this paper we address the problem of determining the period length P and the number of stages (and hence PBC periods) N, assuming the total manufacturing lead time T = N*P is held constant. We present an overview of factors that have to be taken into account when determining suitable values for N and P and treat the inherent trade offs.