Systems to detect overheating train axle boxes to be installed across all MRT lines

The Land Transport Authority (LTA) plans to install systems to detect the overheating of axle boxes - the undercarriage components linked to the wheels - on trains across all existing MRT lines and the upcoming Jurong Region Line.

- Esther Loi

The axle box, which houses the bearings and connects the wheels to an axle rod, was at the centre of a major rail disruption in 2024.

On Oct 31, LTA launched a tender on government procurement portal GeBiz for the supply of hot axle box detection systems. The tender will close at 4pm on Jan 2, 2026.

The Cross Island Line, which will be ready from 2030, is not included in the tender as it is still under construction. The Jurong Region Line will open in phases from 2027 to 2029.

Installing such systems was identified as a measure to detect potential axle bearing failures early, after one such failure caused a six-day disruption to services on the SMRT-operated East-West Line in September 2024, LTA said on Nov 17.

The systems will complement existing measures, such as temperature stickers on axle boxes and current detection systems.

Hot axle detection systems are already installed by rail operators SMRT for its North-South and East-West lines, and SBS Transit for the North East Line.

Excess friction within the axle bearings, due to degraded grease or deterioration of the rubber of the chevron springs, for instance, could lead to the overheating of an axle box.