Study On The Cause Of Abnormal Flange Wear Of Tram Wheel And Its Mitigation Measures

With the rapid development of economy and the accelerating urbanization,traffic congestion and environmental protection are getting more and more attention.The problems caused by the automobile industry are prompting people to look for a greener way to travel.Trams are becoming more and more popular due to their advantages,such as environmental protection,speed and convenience.With the rapid construction of tram lines,some engineering problems have gradually emerged.As the operating condition of the tram lines is poor,the wear of the profile is prominent,especially when the wheel-rail relationship does not match,which can cause the abnormal wear of the profile.This phenomenon reduces the life of the tram and increases maintenance costs.Firstly,this thesis describes the history of trams at home and abroad,and briefly describes the development of wheel and rail wear research at home and abroad.In this thesis,based on the bogie and body structure characteristics of the five-module 100% low-floor tram,dynamic simulation model of the tram was established with the multi-body dynamics software SIMPACK.Secondly,based on field test results,the wear law of wheels with different operating mileage was analyzed,and the contact of wheel and rail was preliminarily analyzed.The wheel-rail contact relationship and dynamic performance on different wear depth profiles were simulated and analyzed.Then,the influence of friction coefficient on wear and vehicle dynamic performance was studied in this thesis.After that,according to the analysis of the cause of abnormal wheel flange wear,the original profile has been optimized,and the wheelrail contact relationship and dynamic performance of the optimized profile and the original profile were compared.The analysis results show that the wear of the profile is mainly distributed on the flange,and when the wear depth of wheel flange reaches 3 mm,that is,the flange width reaches 21 mm,the wheel wear starts to slow down.The analysis of the wheel-rail contact relationship shows that the wheel profile does not match the rail profile.The distribution of the contact points are uneven and not centered and there is obvious two-point contact between the tread and the rail.The analysis also shows that the increase of flange wear depth increases the wheelrail clearance,which is beneficial to the improvement of vehicle dynamic performance and the reduction of contact noise and wheel wear.The analysis on the friction coefficient shows that the friction coefficient has a great impact on the dynamic performance and wear of the tram.As the friction coefficient increases,the wheel wear index increases significantly,that is,oil painting and other technical measures to reduce the wheel-rail friction coefficient can reduce the wheel flange wear.Finally,the optimized design of the rail profile improves the wheel-rail contact.The wear through the curved line,the safety performance,and the stability of the straight line of the optimized profile are better than the original profile.