Deutsche Bahn

DB ESG awarded London Underground Contract

4-year contract by London Underground (LU) for maintenance of the Rail Head Moisture Sensing units

DB ESG is proud to announce that it has been awarded a 4-year contract by London Underground (LU) for maintenance of the Rail Head Moisture Sensing units.

This equipment plays a key role in keeping the network operating, by minimising the delays caused by the infamous ‘leaves on the line’ issue. These sensors provide data to the London Underground Adhesion Controllers Condition Assessment Tool (ACCAT), which is used by LU to predict the onset of slippery track conditions (Low Adhesion) on the Central and Metropolitan lines. This is an essential requirement to enable the operation of Automatic Trains on the open sections during the leaf fall season.

The Rail Head Moisture Sensing units form an important part of the LU Adhesion Management System, as they feed information back to the ACCAT about changes in humidity (rainfall) across the Central and Metropolitan lines. This data is used to update and modify the ACCAT’s “ATO Risk” display, which is provided to the operations control centre.

Slippery conditions occur when there is a combination of leaf deposit on the railhead and a light film of moisture, which occurs most commonly in the autumn leaf fall season. This combination results in a significant reduction in friction between the train wheels and the rails, leading to extended braking distances, resulting in significant service disruptions and delays, especially if incidents occur during the rush hour periods.

Commenting on the new contract, DB ESG’s Managing Director, Martin Horsman said: “DB ESG has been selected by London Underground because of its expertise in Brake System Technology. DB ESG’s Wheel Slide Protection Evaluation Rig (WSPER) is used to evaluate the low adhesion braking performance of a train braking system. This facility is used by London Underground as its default testing facility for new WSP (wheel slide protection) system applications and more recently for the evaluation of the performance of a sander system. We are looking forward to a continued successful partnership with London Underground.”