In early October, Metronet Rail and Tube Lines, brought into service a modified rail-roader Land Rover to assist with rail defect detection on the UK’s London Underground.
The companies are responsible for maintaining and revitalising the London Underground network. The use of such a vehicle, supplied by Sperry Rail, is believed to be a first for the London Underground. In order to run on the tracks, the Land Rover is fitted with rail wheels. It tows a trolley fitted with ultrasonic detection equipment to assist in the identification of track irregularities at an early stage.
Although ultrasonic rail flaw detection is currently used, it is carried out using handheld detectors by a team of three or four workers. This limits the length of rail that can be inspected in a nightshift to roughly 4.8km. The commissioning of Sperry Rail to mount their equipment on a rail travel equipped Land Rover means that the frequency of testing and quality of data captured can be improved. With the Land Rover travelling at up to 16km/h, the distance capable of being tested during engineering hours has been quadrupled to 20km.
An improved testing regime was instigated following a derailment in October 2003. Tube Lines’ director of operations, Stephen Peat, said: “This development will really help us modernise the way the Tube is maintained. We are now building towards a situation where we will know the condition of the entire network at any one time together with the rate of wear at any point so that rail replacement and maintenance can be carried out on a much more scientific and planned basis.”
The road-rail vehicle is an interim measure while a fully automated train is developed that can run during the passenger service to record track conditions.
