A Risk-based Model for Inspection and Maintenance of Railway Rolling Stock

Along with the widespread use of high-speed vehicles and the increasing level of traffic on railroads, maintenance management of rolling stock assets is considered to be an area of high priority. In the past, the planning of inspection and maintenance activities for rolling stocks has been based on the accumulated knowledge and experience of train operating companies, rolling stock owners, original equipment manufacturers and vehicle refurbishment companies. However, current research efforts are focused on the development of risk-based maintenance approaches with the major goal of reducing whole life costs while ensuring a high level of transport safety and service quality. This paper presents a novel risk-based modelling approach for the inspection and maintenance management of railway rolling stock assets. A quantitative model is developed to evaluate the time-variant risks associated with different types of failures of rolling stock components. To this aim, the root causes of failures are investigated and a probabilistic method is proposed to estimate the likelihood of occurrence of a failure. The failure consequences taken into account include the costs of inspection, maintenance and repair, the penalty charges due to train delays or service interruption, and the costs of loss of reputation in relation to train cancellations. For the purpose of clearly illustrating the proposed analysis approach, a case study of the Class 380 train’s pantograph system operating in a Scottish company is provided and the results are discussed. The model presented in this paper not only provides the capability to assess the current maintenance practices within the railway transport industry but also helps the maintenance engineers to propose or initiate improvement actions when needed.