Greasing the wheels

Urban rail network Merseyrail is testing Intelligent Wheel Flange Lubrication (iWFL), a train-mounted lubrication system that claims to release exactly the right amount of lubrication for track conditions.

The iWFL system was developed by rail systems specialist Rowe Hankins of Bury and it will be fitted to a Merseyrail 507 electric multiple unit for trials beginning this month.

The trial was prompted by a period of increased wheel flange wear in 2007, which had a significant impact on vehicle availability and increased rail wear, disrupting services. The cause was identified as a reduction in the effectiveness of track-based lubrication systems, which prompted the idea of supplementing them with an on-train variant.

There are currently around 120 track lubricators located at critical points around the network, all of which are maintained manually and some of which are located in tunnels where access is restricted.

The Rowe Hankins system combines proven lubrication distribution technology from German company REBS, a major supplier to European train builders and operators, with control systems from Rowe Hankins that make it suitable for UK rail networks.

The control system memorises the route and by means of speed and distance sensors and a curve-detection device can pinpoint the location, severity and duration of curves. This allows pulses of lubrication to be applied to the wheel flanges as the train enters and goes through a curve. Detection of left and right-hand curves allows proportionately greater lubrication to the outer wheel of a wheel set.

The initial trial period will last six months during which wheel and rail wear will be monitored. Engineers will regularly inspect and top up the systems as needed to maintain performance and establish the amount of lubricant used and service schedule.