Evaluation of technical vs economic decisions in rail grinding
Rail is a significant capital asset for railway companies. It contributes more than half of the capital assets of railway infrastructure. Recent rail inspection data using Ultrasonic rail testing has shown increasing number of rail defects, failures and causing disruptions to rail services. This cost can be further increased when the track quality is poor. In recent years, railroads have been purchasing over 500,000 tons of rails per year at an estimated total cost of US $1.25 billion for replacement of worn out and degraded rails. Rail grinding is considered as viable means in reducing the impacts of rail defects and failures. Rail grinding can result in improved curving performance (wheel/rail interaction) and prevents crack initiation and propagation of surface cracks due to RCF. This paper focuses on analysis of rail degradation process and development of mathematical model considering technical and economic decisions in rail grinding to rail infrastructure owners.
The current status of theory and practice on rail integrity in Japanese railways—rolling contact fatigue and corrugations
The paper describes the Japanese understanding and practice with regard to wheel rail interface problems and their management. Rolling contact fatigue, especially squat defects, grinding, corrugations and lubrication, have been considered. The understanding has been developed through a combination of theoretical modeling, laboratory-based experiments and field trials. Measures have been introduced to mitigate the detrimental effects of these problems and are resulting in benefits to the Japanese railway companies. However, more work is required to better understand wheel rail interface problems and to provide effective solutions.
The effect of lateral creepage force on rail corrugation on low rail at sharp curves
In Japanese narrow gauge lines, short pitch corrugations on low rail at sharp curved track whose radius of curvature is less than 600 m pose very large problems that are noise and track deterioration caused by large vibration excited with interacting forces between rail and wheel. This paper describes the lateral force has great influence on the formation of short pitch corrugations on low rail and the effect of the lubrication on low rail to reduce lateral force on preventing the formation of corrugations through a couple of years investigation on a revenue line as a countermeasure.