Il begins the seasonal struggle
modules that it uses to combat the autumn problem. It uses water jets to blast the leaves with 92 litres of water per minute at a pressure of 1500 bar. It’s that strong that if you were to place your hand under the jet, it would cut right through it! Likewise, the train must always be moving when spraying, otherwise the rail will be cut.
The other treatment is sandite, a gel containing sand and steel or iron shot, which provides adhesion for trains.
NR says that which module is deployed depends upon the needs of individual routes, but its arsenal of weapons against the weather includes 67 water jet modules, 108 adhesion modifier modules, 135 RHTT water tanks and 40 APUs (auxiliary power units that supply air and electric to the trains). One RHTT tank holds 17,000 litres of water, and a three-tank formation can work for 12 hours straight.
Last year’s autumn treatment covered some 1.7 million miles, which according to Network Rail is the equivalent of travelling to the moon and back three and a half times. And the number of sites treated by the trains has more than doubled in the past decade. Davis adds: “There are lines that historically have more trees than others.”
The requirements vary from region to region, as you would expect. This year, NR says that in the London North Western region there will be eight trains covering 102,000 miles over ten weeks, spraying 32 million litres of water. In the Midlands, four trains will operate purely on the CrossCity lines, covering 6,000 miles in the same period, spraying one million litres of water.
There are other ways of dealing with the problems caused by the autumnal weather.
In Anglia, Network Rail has installed 43 traction gel applicators at high-risk locations on its route. These automatically apply traction gel to the track every time a train passes. This is then collected by train wheels and is carried along - thus treating track and train at the same time.
There is also a ‘sand rover’ in use. This is a rail-adapted road vehicle specifically designed to scrub tracks with brushes and apply a layer of gel to treat the Sudbury line, during peak leaf-fall season. This is because RHTTs cannot access the branch easily. NR also has engineers along the route working all year to manage vegetation, so that when the leaves fall they create less of a problem.
On the operational side, to combat the problems of the past, Greater Anglia has had its Class 15x fleet fitted with wheel slip protection (WSP). This is the first time the technology, commonly found on new trains, has been fitted to Sprinters dating from the 1980s.
Vegetation clearance is currently an emotive subject, with the Woodland Trust criticising Network Rail’s treatment of trees ( Comment, RAIL 863), and Rail Minister Jo Johnson commissioning a report into said actions.
Davis responds: “It is a balance. We need to cut the vegetation to make sure the railway is safe, but we have to balance it against the needs of the local communities.”
Once December 13 arrives, which is NR’s planned end date for the autumnal treatment, there is no rest. Attention then turns to snow and ice. The MPVs at Tonbridge, displayed to the press on September 28, will be used in that fight, as will the recently acquired Snow and Ice Treatment Trains (SITT).
For Network Rail, the battle against Mother Nature never stops. ■ In the next issue (published November 7), RAIL travels on a railhead treatment train to observe first-hand how the problem of leaves on the line is being tackled.