A simulation-based method to aid the improvement of manufacturing flexibility

Abstract

Manufacturing organizations today are under increasing pressure to supply high quality products with short delivery times and at low cost. These competitive pressures make it essential for the company's manufacturing resources, whether a highly automated or traditional manual system, to be operated in the most efficient and flexible way possible. One useful measure of the flexibility of a manufacturing system is the manufacturing lead times of its products: shorter lead times contribute to greater flexibility. The drive for reduced lead times is an important aspect of the Just-In-Time (JIT) manufacturing philosophy. JIT is normally seen as an essentially experimental process of continuous small improvements, achieved by exposing one constraint at a time and eliminating its cause. However, this process often involves a risk of disruptions to production as problems come to light. This paper proposes an approach to achieving lead time reductions without the need for the risks of disruption involved in the normal JIT approach. If a simulation model of the manufacturing system is used for the experimental aspects of implementation, rather than the real system, then many of the problems might be anticipated, and hence addressed, before production is affected. The approach is based on the use of a simulation model to evaluate the overall performance of the system under given conditions. Proposed enhancements to the system can then be evaluated to assess their impact before the need to implement the changes in the real system. The approach is illustrated by its application to the problem of batch size determination and its effects on lead time performance. Results indicate that the approach may be suitable for application in a wide range of manufacturing companies.