Application of grinding to reduce rail side wear in straight track

Abstract

A stretch of straight rail on the Jing-Hu railway in China has been suffering from unacceptable levels of side wear. This phenomenon has not previously been investigated. This paper reports on work to analyse the causes using actual wheel and rail profiles from the track where it has occurred and a novel contact assessment approach and possible mitigations. By running a range of dynamic multibody simulations, it was shown that static calculations are adequate to represent the contact conditions that cause the wear. Almost 7000 wheel profiles were measured and their contact with the relevant rail profile calculated. It was predicted that freight trains whose wheels have a large rolling radius difference, would rub on the gauge corner and gauge face, thus causing the wear. This finding was consistent with field measurements.Two grinding strategies were developed that could reduce the number of damaging contacts. These were, grinding the gauge shoulder, and grinding the field side of the top of the rail. Calculations predicted that the largest improvement would result from combining both strategies. This approach was adopted to reduce the side wear on rail in straight track. It was found that the distribution of wheel/rail contact points on the rail surface agreed well with the calculation results, and the proposed grinding regime did reduce side wear.