Abstract
The study highlights the necessity to specify the safety factor against derailing of the wheels of a railway rolling stock. The modeling of the wheels’ derailment was carried out on the basis of considering the complete pattern of frictional interaction with the rails of the approaching and running-off wheels of a wheel pair.The simulation included the following previously overlooked factors: the dependence of the vertical component of the frictional force in the flange contact of the approaching wheel on the angle of the wheel running onto the rail; the influence of the frictional force in the flange contact of the approaching wheel on the increase in the horizontal lateral load on the flange; and the influence of the frictional force in the contact of the running-off wheel on the increase in the lateral load on the flange of the approaching wheel.The study has specified the safety factor – the Nadal criterion – against the derailment of the wheels of a railway stock. Unlike in the traditional approach, the safety factor of the wheel steadiness against derailment is assessed taking the frame force, rather than the lateral load on the flange, as the main factor of safety. This approach to determining the stability criterion gives more reliable results, since the frame force is more accessible for experimental and theoretical analysis.The proposed safety factor against the derailment of a railway stock, for different values of the flange inclination angle and the friction coefficient, is 10–50 % lower than the classical Nadal stability criterion. This makes the proposed criterion more reliable in assessing the safety of a railway rolling stock derailment
Highlights
It is established that the factor of stability against the rolling of the wheel flange onto the railhead is an integral indicator of traffic safety. This figure is determined taking into account the vertical load, lateral force, frictional forces in the contact of the flange of the wheel with the rail, and the geometrical parameters of a wheel pair
Safety factor against derailment The critical relation of the frame force to the vertical load at which the main contact is completely unloaded can be found by the formula tgβ 1- m2 m ⋅tgβ +1
The improvement is based considering the complete model of the wheel pair contacting, taking into account the slip forces at the contact points of the approaching and running-off wheels
Summary
The most frequent (up to 25 %) among the main causes of disasters, accidents and serious incidents in the railway transport is derailing. It is established that the factor of stability against the rolling of the wheel flange onto the railhead is an integral indicator of traffic safety This figure is determined taking into account the vertical load, lateral force, frictional forces in the contact of the flange of the wheel with the rail, and the geometrical parameters of a wheel pair. The joint influence of the wheel-on-rail angle on the rail and the effect of the slip forces on the process of the wheel pair derailment have not been adequately investigated Both from a practical and theoretical point of view, the estimation of the safety factor for the lateral force in the flange contact is inconvenient and inaccurate. Given the importance of the issue of traffic safety in railway transport, it seems appropriate to redefine the safety criterion based on a study of factors that have not been taken into account yet
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Eastern-European Journal of Enterprise Technologies
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
