Speed rails
Profile-optimized support rollers have been used in a real underfloor wheel lathe, showing good results. Simulations of re-profiling process have been carried out by the finite element method showing that the designed roller profile reduces drastically the impact/damage during the operation.
This novel profile design will minimize damage and increase the safety of such lathes, since it proposes a greater smoothness in the process. In this article, a methodology to optimize the profile of the support rollers used in underfloor single tool lathes for railway wheel re-profiling is proposed. On the other hand, with single tool lathes, re-profiling is not smooth or safe enough when current convex profile support rollers are used. Multi-cut tool lathes have the disadvantage of being extremely expensive. Underfloor wheel lathes are the most appropriate tool to achieve this double objective, and therefore the most used nowadays. Avoiding wheelset disassembly means considerable time savings, while reducing wheel damage during operation.
#SPEED RAILS HOW TO#
Researchers and railway operators have been very concerned about how to minimize the loss of time during wheel re-profiling without decreasing safety. The wheel re-profiling is an important part of railway wheelset maintenance.
Furthermore, the effective equivalent conicity is a good choice to establish the relationship between the wheel–rail contact geometry and the carbody hunting stability. The simulation results show that keeping the rail cant at about 1/40 and reducing the track gauge and the wear depth at the gauge corner of rail can improve the carbody hunting stability of the electric locomotive. The nominal equivalent conicity, the effective equivalent conicity and the wheel–rail contact bandwidth for a wheelset lateral displacement of ☖ mm are used to evaluate the wheel–rail contact relationship, while the lateral continuous comfort index is used to evaluate the carbody hunting stability. A group of rail profiles are obtained by interpolating between the standard CHN60 profile and the worn rail profiles. The focus is on the influences of track parameters (including rail profile, rail cant and track gauge) on wheel–rail contact relationships and carbody hunting stability. To fully understand the correlation between the wheel–rail contact relationship and the carbody hunting stability of an electric locomotive, the wheel–rail contact geometry analysis and the multi-body dynamics simulation are carried out in this work. At the end, we supply our perspective about opportunities and challenges for future research and development on the mechanics of high speed rail.Ĭarbody hunting stability has attracted more and more attention due to its great influence on the dynamic performance of a railway vehicle. In this review paper, we summarize current research progress covering aerodynamics, catenary-pantograph interaction, dynamics and related issues of carbody, stability analysis, rail-wheel interaction, reliability of key components, and mechanisms about noise-generation. With the privilege of involving in the construction and operation of such a large scale and long distance HSR network, researchers and engineers in the field have gained systematic and deep understanding about the dynamic system composed of train, wheels and rails, catenary and pantograph, and aerodynamic resistance.
In the past decade, China Railway High-speed (CRH) has undergone numerous technological innovation to ensure their safe, eco-friendly, and economical operation. As a result of the "Speed Up" campaigns initiated in the end of last century when commercial train service averaged 48 km/h, China now has the world's longest high speed rail (HSR) network.