Figure 1
The diagram illustrates the operational workflow linking detection, operations, and maintenance for hot axle box and hot wheel monitoring. It consists of three vertical panels arranged from left to right. The left panel, titled “Detection (H A B D/H W D + A V I/R F I D)”, represents trackside detection systems. Hot Axle Box Detectors (H A B D) and Hot Wheel Detectors (H W D), supported by automatic vehicle identification (A V I) and R F I D, generate alarms classified as warning, alert, or critical. The central panel, titled “O C C (alarm classification, decision tree, operational response)”, represents the Operations Control Centre. Here, incoming alarms are assessed using predefined classification rules and decision trees to determine the appropriate operational response, including continued operation, controlled stop, or immediate intervention. The right panel, titled “Maintenance (E C M/C M M S, work orders, interventions)”, represents maintenance management systems. Validated alarms trigger work orders in the Entity in Charge of Maintenance (E C M) and Computerised Maintenance Management System (C M M S), leading to inspections and corrective interventions. Directional arrows indicate information flow: alarms pass from detection to the O C C, operational decisions are fed back when required, and confirmed alerts generate maintenance actions. The diagram highlights the closed-loop integration between detection, operational decision-making, and maintenance execution.Operational flow of HABD/HWD alarms across detection, OCC and maintenance processes. Source: Authors’ own work, informed by operational practices from ADIF (Spain), Network Rail (UK) and Indian Railways EHMS