Singapore’s Land Transport Authority (LTA) has announced plans to install a comprehensive axle box overheating detection system across all existing Mass Rapid Transit (MRT) lines by 2028. This initiative aims to enhance rail safety and prevent disruptions similar to a significant incident that occurred in 2024.
The new system, which monitors the temperatures of axle boxes and gearboxes on passing trains using trackside infrared sensors, will be deployed on the North-South, East-West, Circle, Thomson-East Coast, Downtown, and North East lines. Installation is scheduled to begin in 2027. The Jurong Region Line (JRL), which is set to commence operations in phases between mid-2028 and 2029, will have the detection system installed by the end of 2030. A new station linking Tengah and Choa Chu Kang is expected to open by the mid-2030s.
This move follows a major six-day service disruption on the East-West Line (EWL) in September 2024 caused by an overheated axle box that led to a derailment and extensive track damage. The incident damaged about 2.55 kilometers of track and trackside equipment, suspending train services between Jurong East and Buona Vista stations. Investigations revealed that the axle box's temperature reached abnormal levels before the derailment, but existing detection systems failed to pinpoint the affected train due to technical shortcomings. These issues have since been addressed.
The contract for the new monitoring system, valued at roughly S$12.5 million, was awarded to Chengdu Shengkai Co., a Chinese railway safety equipment manufacturer. The new system will standardize the detection equipment across the network, replacing existing systems operated by SMRT on the North-South and East-West lines and by SBS Transit on the North East Line. This standardization is expected to streamline spare parts management and technical support.
In addition to the infrared-based overheating detection, two complementary systems will be introduced to improve early fault identification. An acoustic detection system will be implemented on the North-South, East-West, and Jurong Region lines. Using trackside microphones and predictive analytics, it will detect early damage to axle bearings. A hot wheel detection system, which monitors wheel temperatures to identify potential wheel and brake faults, will be rolled out on all MRT lines, including the JRL.
Axle boxes house the axle bearings that enable smooth wheel rotation, and overheating can result from factors such as worn grease or degradation of the rubber components in chevron springs—metal plates bonded with rubber that dampen vibrations. The Cross Island Line, currently under construction and expected to open in 2030, is excluded from the current upgrade plan.
The LTA’s enhanced monitoring efforts underscore a commitment to improving MRT system reliability and passenger safety by addressing the mechanical vulnerabilities that pose operational risks.