A stochastic model of the logistics actions required to ensure the availability of spare parts during maintenance of railway vehicles

Abstract

Models that can predict the correct logistics actions that need to be taken to ensure the availability of spare parts during maintenance of railway vehicles are of considerable interest. Since the occurrence of defects is a random phenomenon it is not possible to know in advance what spare parts will be required at any point in time. This situation requires the creation of a stochastic model that can incorporate uncertainty. Deterministic and stochastic models of maintenance logistics are based on the assumption of a non-zero stock level of spare parts. Carrying an extensive inventory of parts requires a large financial outlay and it is still often the case that a required spare part is not immediately available and has to be obtained. This paper shows, provided certain conditions are met, that it is possible to create cost-effective maintenance procedures even if the required spare part is not immediately available. Thus, the amount of money locked up in stock can be effectively regulated, thus reducing operating costs.