The bad winter of 2010/2011 caused Network Rail so many problems with snow and ice build up on the rail infrastructure that it decided to commission a service train dedicated to tackling the issues. Garrandale was successful in winning the contract to design and build the steam/hot water and compressed air modules for the train. These were produced on a very tight delivery, mounted on the train and sent to Scotland for trials during the winter of 2011/2012.
These trials resulted in a number of specification changes being requested on the whole train, including the main control wiring which, again, Garrandale successfully bid for. Following the award of the contract, the main vehicles of the train were delivered to Garrandale in early October 2012 with the work on all the equipment completed by mid December. The train will now be sent to Scotland for more trials this winter.
A combination of steam, hot water or air blasts can be deployed from modules to clear the snow and ice, together with large hot air blowers directed down onto the track. Using high pressure steam/water lances when working under the overhead lines is a significant and unacceptable risk, so Garrandale engineers have developed a fail-safe cut off which senses if the lances move from the down hand position by more than ± 40°. This utilises twin sensors on the lance handle with a cross monitored safety relay driving a fail-safe cut off valve.
The complete system has been designed to operate in temperatures as low as -20°C and, as any system failure when the equipment is deployed would be a serious issue, high levels of redundancy with flexible configuration of back-up units have been built in. To illuminate the working areas, an array of the latest high power LED flood lights are arranged on either side of the modules. Although the electrical system is powered by an onboard diesel generator, as an extra safe guard, these lights are battery backed with a life of 4 hours, without charging.
To combat the extreme conditions anticipated and maximise the internal space available, the two main modules are insulated with a high performance material that was previously used in space vehicles. In addition, all of the key elements such as water storage, steam generation and air compression equipment, are fitted with their own heaters to prevent damage from freezing.