Validation of production system throughput potential and simulation experiment design

Abstract

The throughput potential of a production system must be designed and validated before implementation. Design includes creating product flow by setting the takt time consistent with meeting customer demand per time period and the average cycle time at each workstation being less than the takt time. Creating product flow implies that the average waiting time preceding each workstation is no greater than the takt time. Kingman's equation for the average waiting time can be solved for the variation component given the utilization and the cycle time. The variation component consists of the variation in the demand and the variation in the cycle time. Given the variation in demand, the maximum allowable variation in cycle time to create flow can be determined. Throughput potential validation is often performed using discrete event simulation modeling and experimentation. If the variation in cycle time at every workstation is small enough to create flow, then a deterministic simulation experiment can be used. An industrial example concerning a tier-1 automotive supplier with two possible production systems designs and various levels of variation in demand assumed is used to demonstrate the effectiveness of throughput validation using deterministic discrete event simulation modeling and experimentation.