Development And Application Of New Profile Of 60N Rail

In recent years,no matter heavy load railway or high-speed railway in China,there are different degrees of damage,especially the serious rail is increasing exponentially year by year,the number of fatigue damaged rail is increasing more prominent,especially the new rail with small curve radius is more damaged,and the forms of damage are mostly short period and rapid development.In order to further deal with the increasing driving speed and stable driving safety,and to solve the problems of rail damage and rapid development in curve line.Whether the shape matching of wheel and rail is appropriate or not plays an important role in the operation quality of EMU,the service life of wheel and rail and even the operation safety of railway.At present,under the existing EMU operation conditions,there are some problems in the matching of wheel rail profile in China's railway,which mainly shows that the wheel rail contact area is not in the designed rail head tread center,especially for the freight car wheels with large axle load.When the wheel cannot run in with the rail for a long time,it will lead to the early rolling contact fatigue damage of the high hardness heat treated rail used on the straight line and the peeling off or even nuclear damage of the rail on the curve;at the same time,it will cause the lateral acceleration of the high-speed EMU to exceed the limit,so it is urgent to optimize the wheel rail contact surface.Referring to the experience of improving wheel rail matching abroad and combining with the existing line operation in China,the new profile size design of 60 kg / m rail is carried out.After the completion of the design,the contact analysis of the optimized new profile is carried out by using ABAQUS finite element analysis software,and the contact points and contact stresses of the new profile and the new profile in the straight and curved sections are simulated and compared.The results show that the contact positions of the new 60 N rail significantly tend to the center of the rail head tread,the contact area increases,the maximum contact stress and the maximum Mises equivalent stress It is proved that the new profile rail can effectively improve the wheel rail contact relationship.According to the geometrical dimension of the new profile,combined with the existing process equipment conditions of Baotou Steel Plant,thesteel grades with good supply and stable production at that time were selected,and the mature chemical composition was used to design the new pass system and the mature controlled rolling and controlled cooling process.Through scientific research and experiments to stabilize the production process,and through the follow-up of the product batch performance test and track the use of the track was verified.After two years of tracking observation,the 60 N rail with qualified quality is laid on the experimental curve section.Based on the change of rail profile,it is analyzed that the new 60 N rail profile can change the wheel rail contact stress point through the change of rail crown size,so as to effectively relieve the rail contact fatigue of gauge angle,make the wheel closer to the center of rail head tread,uniformly stress,and make the wheel rail produce periodic stability The fixed abrasion can prolong the service life of rail and wheel,which is more safe for heavyduty railway operation.