Evaluation of Locomotive Wheelset Maintenance Strategies Using Petri Net Modelling for Wheelset Life-Cycle Management Under Workshop Resource Constraints

Locomotive fleet management is a key factor in ensuring safe, reliable, and cost-efficient railway operations. Among the essential maintenance tasks in railway transportation is the monitoring and management of wheelset condition, as wheelset degradation directly affects operational safety, ride comfort, and maintenance expenditure. This study presents a Petri net-based modelling framework to represent the wheelset flange and tread degradation process, enabling the evaluation of various maintenance and inspection strategies for locomotive wheelsets. A distinctive feature of this approach is its ability to simulate the degradation process of multiple wheelsets simultaneously. By systematically varying inspection and maintenance policies within the simulation, the model allows assessment of their impact on the key performance indicator, which is wheelset lifespan. Additionally, the model tracks the time that wheelsets operate outside permissible limits, enabling the evaluation of associated safety risks during locomotive operation. The proposed methodology supports dynamic, data-driven decision-making on wheelset maintenance strategy, aiming to extend wheelset lifespan, maximise locomotive utilisation time, and reduce maintenance costs while maintaining high safety and reliability standards. Furthermore, the framework enables the assessment of how different maintenance strategies influence workshop capacity, considering reprofiling machine utilisation, inspection position availability, and workforce constraints. This capability provides valuable insights for locomotive maintenance planning and resource allocation, allowing railway operators to develop suitable locomotive maintenance policies. The study outcomes allow comparison and selection of the most appropriate wheelset maintenance strategy under the given system constraints.

Keywords: Petri Net, modelling, simulation, fleet management, asset management, locomotive, rolling stock, wheelset, maintenance strategies, life-cycle.