Alternatives to sand
Sanders, which blast sand between the wheel and the rail, are an effective and proven way of reducing the impact of slippery rail head conditions. Understanding how sand particles are entrained into the wheel/rail interface, the effect these particles have - in terms of interface friction, leaf film removal, and wheel/rail contact (which can affect track-circuits) - could reveal opportunities to improve sanding.
Innovative new materials, as alternatives to sand, could help to improve braking performance in low adhesion conditions. Freight locomotives in Japan and Taiwan, for example, use a mixture of silica sand and ceramic particles (which can withstand higher forces than sand) known as Cerajet to help break up the leaf film that forms on the railhead. Magnetic particles such as iron, added to sand, could help with particular track circuit operation. This would open the door to the creation of ‘sand’ that combines ceramic and magnetic particles in a balance that can be optimised according to adhesion conditions.
The rail industry can also learn from, and potentially harness, innovation from other sectors. Powdered ‘nano-rubber’, for example, is used in manufacturing to substantially improve the properties of friction materials and reduce wear rates. Similarly, the hydrophobic and superhydrophobic agents used in the oil and horticultural industries could help the rail industry manage railhead moisture levels.
If you are interested in the opportunities associated with the use of sand additives and alternatives to sand and would like to work with us on the journey towards reaping their benefits on the operational railway, do get in touch.
- Sand particles
- Ceramic particles
- Magnetic particles
- Nano rubber
- Hydrophobic materials