Calculation of the Throughput-Time in Simple Assembly Lines with Learning Effect

Abstract

Calculating the throughput-time of a production run in simple assembly lines is important for several reasons. For example, the length of time to complete a production order is required for planning and scheduling production or the evaluation of throughput-time is required by any effort to improve assembly operations. Classical assembly line balancing techniques assume a constant cycle time. In this case, the calculation of the throughput-time is straightforward. In case of the presence of learning effect, however, cycle time changes for two main reasons. First, cycle time continuously decreases because of the decrease of operation time of the bottleneck station as a consequence of learning. Second, bottleneck may shift from one station to another, causing further changes of the cycle time. In this paper, an algorithm is presented to determine the throughput-time of a production run at the presence of learning based on the residence time of the workstations in the bottleneck. The algorithm and its application are illustrated with a simple example.