With the rapid urbanization, transportation demands are rising steadily, and urban rail transit has become one of the most effective means to meet this demand. The operational availability and cost-effectiveness of urban rail systems largely depend on the efficiency of their maintenance strategies. This paper presents a comprehensive case study focused on enhancing the 3- monthly (3M) periodic preventive maintenance process of a light rail vehicle fleet. The methodology begins with an initial work study to analyze current maintenance procedures and establish a performance baseline, which revealed critical inefficiencies and time losses. These inefficiencies were then systematically addressed through targeted engineering modifications combined with lean manufacturing principles. A follow-up work study was conducted to quantitatively assess the impact of the applied improvements. Results indicate that the Mean Time To Repair (MTTR) was reduced by 30. 6% (from 14. 30 h to 9. 92 h), and the non-value-added ‘Waiting Time’ was decreased by 43%. Furthermore, the economic analysis projects an annual labor cost saving of approx. 20, 000, with a return on investment (ROI) period of just 3 months. The novelty of this study lies in its integrated, data-driven framework that connects detailed process analysis with real engineering interventions, offering a replicable model for optimizing preventive maintenance in urban rail systems.
Dinçer et al. (Fri,) studied this question.