Development of wayside rail curve lubrication model for Australian heavy haul lines

Wheel and rail wear and ineffective lubrication are serious concerns for rail operators around the globe. These assets have to be maintained and operated effectively to maximise the benefits to the stakeholders and minimise the cost to rail operators. Proper management of the wheel/rail interface helps the rail industry to grow business, improve reliability of service and commitment to their clients. Rail wear and effectiv lubrication are significant issues that have direct impact on operating costs of the rail operation. Wear causes detrimental effects on rail/wheel life and maintenance costs. Thus a better understanding of causes, mechanisms and effects of wear at the wheel/rail interface is necessary. Lubrication is considered as one of the most effective maintenance programs to reduce wear, energy consumption and noise. Therefore, implementation of an effective lubrication program is necessary to achieve cost effective rail operation. The wayside lubrication method is widely used in the rail industry. In the past, lubricators were installed either too close together or too far apart. The literature indicates that quite a few approaches have been attempted for developing an effective placement model for wayside lubricators. There are different types of lubricators, lubricants and a variety of lubrication strategies across different networks, and also within the same network. A critical literature review revealed that there is a need for a more scientific approach to develop a reliable rail curve lubrication model. Keeping this fact in view, field investigations were carried out on the live track in the current study with the assistance of maintenance team of the Australian heavy haul network operators. The first observation revealed that the grease carried by the wheels lasts only a few meters from the wayside lubricator sites in many curves. The performance of lubricants in the track can vary significantly depending on the weather conditions, track characteristics, dispensing equipment, type of lubricant being used and maintenance activities. In this field study it is clearly identified that there is a need for an improved understanding of the effect of lubricator performance, applicator bars (short and long bars) and locations of the bars based on track geometry, direction of traffic etc. Proper application of wayside lubricators also includes selection of appropriate equipment and a suitable lubricant for the known operating conditions, measurement and management of the lubrication effectiveness, positioning of lubricators and their appropriate maintenance. Wayside lubricator spacing for maximum benefits is directly related to the lubricant carry distance. Whereas, carry distance is affected by track type, traffic, lubricant and the lubricator itself. Hence, there is a clear need to develop an improved lubricator placement model based on the combined effects of lubricants, applicator bars, lubricator, locations and track/traffic characteristics. The scope of this study also includes the survey of the current practices of curve lubrication and assesses their effectiveness; develop a hierarchical wayside lubricator placement model based on the evaluation of effectiveness and cost/benefit analysis and set up a standard practice for lubrication of heavy haul lines. A detailed review on currently available technologies applicable for heavy haul lines was performed. This was followed by the field investigations for real data collection to confirm the performance evaluation, development of lubricator placement model, cost/benefit analysis, model development of the grease transport mechanism, and optimisation of modelled parameters. The study concluded that electric lubricators are highly reliable and effective compared to older technologies, long applicator bars in the tangent track with high quality grease generate the longest carry distances and short applicator bars in the transition curve, even with high quality grease, didn't achieve long carry distances. The rate of grease application is very crucial from the perspective of both effectiveness and economic returns. It is also known that equipment, their limitations, performance, appropriate location, quality of installation and their maintenance, various properties of greases and column strength of the grease bead contribute significantly to the grease transport mechanism. This study suggests that to ensure the effectiveness of way side curve lubrication, remote condition monitoring could be an effective tool which can significantly improve the reliability, maintainability and operating cost of electric lubricators.