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Wayside gauge face lubrication is widely used to minimize rail wear. Scientific understanding of this process is limited; however, there have been significant recent improvements in application equipment. In this paper the process is analyzed in terms of a number of interacting sub-processes, and the factors thought to be important for lubricant and application equipment are reviewed. Wheel/rail contact conditions (pressure and temperature) are also identified as significant variables. Grease stability and retentivity are significant factors that affect lubricant performance; however, significant knowledge gaps exist about the factors that influence grease pick up and carry down especially at the extremes of operating temperatures. Laboratory (two-roller rig measurement of retentivity) and field evaluation (rail friction measurements of carry down) gave the same relative ranking for the tested grease samples. Areas for future research in the area are identified.

To investigate the mechanisms behind rolling contact fatigue (RCF) and wear, a collaborative test program was conducted by voestalpine Schienen GmbH (Leoben, Austria) and Kelsan Technologies Corp. (a part of LB Foster Friction Management) on the full scale test rig of voestalpine. A reference grade was compared to a series of pearlitic rail grades under dry and friction modifier (FM) contact conditions. Rail and wheel profiles were collected at predefined intervals, allowing the calculation of wear rates. The initiation and development of RCF cracks were monitored using optical means and magnetic particle inspection. Metallographic sectioning of the samples was conducted to characterise crack growth and crack orientation as well as the evolution of surface and subsurface material flow. Additionally, the test rig results were compared to the results obtained from the extensive track test network of voestalpine and Kelsan to outline similarities and differences between test rig conditions and the conditions in track. The combination of rail grade, FM application and an appropriate maintenance strategy is seen to have a significant effect on the development and propagation of wear and RCF. This offers a huge potential for reducing the track LCC costs for the infrastructure owners.

Shuohuang Railway (SHR) is one of the major coal carriers in China, with a total network length of 590 km running from Shenchi to Huanghua. Significant increases in annual operating tonnage have generated accelerated rail wear and rolling contact fatigue (RCF) growth problems for many sharper/lower radius curves. In order to address these rail problems, SHR is interested in the state-of-the-art total friction management (TFM) technology currently deployed by some North American heavy haul freight railroads and is evaluating the impact of TFM via a field trial at SHR's Yuanping subdivision. This paper presents an evaluation of the effect of TFM, which includes both wayside gauge face lubrication and wayside application of a thin film top of rail friction modifier on control of lateral forces, rail wear and RCF.

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