Global Analysis of a Multi-Product, Multi-Line Production System Using Q-GERT Modeling and Simulation

Abstract

Numerous techniques and algorithms have been developed for the analysis of production flow line systems. However, due to the complex nature of such systems, it is often possible to analyze only a small segment of the production line system at one time. When solution designs result from this analysis and are then implemented within the overall system, inefficient results can and frequently do occur. As such, an overall methodology is needed to analyze complex production line systems in their entirety. Q-GERT network modeling and simulation offers unique possibilities for this purpose. Q-GERT, a derivative of GERT network modeling, includes such features as probabilistic branching, network looping, multiple node realizations, and queue nodes which make it applicable to complex network forms such as production flow lines. In this paper Q-GERT is demonstrated as an appropriate vehicle for analysis via a detailed case example of a multi-product, multi-line production system. The production system is first described in general terms and then modeled as a Q-GERT network. Simulation results for the network are presented for daily and weekly run durations. In conclusion, various applications of the Q-GERT model to topics such as line-balancing, production planning, job design, and system design are discussed.