Analysis On The Causes Of Rail Wear And Control Measures Of Hong-ning Railway

The Hongliu Lin — Shenmu West Railway is a special railway line in charge of coal transportation task in a national energy chemical base,a north Shanxi energy chemical base.Local grade I single line railway,limited slope 13‰,minimum curve radius 800 m,traction mass 5000 t,electric traction(SS4),effective length 1050 m to the starting line to connect with the permitted channel capacity 45Mt/years.As the volume of transport increases sharply,especially since Shenmu C80 heavy-haul trains to the west in 2015,the diseases of line equipment are frequent,and the diseases such as rail wear,fat edge,fish scale injury and crushing occur frequently,especially in curve section,The running speed of the vehicle does not match with the linear condition,the car body moves horizontally,and the flange and rail side are attached to each other,which leads to the side wear of the rail.The rail side grinding has a great influence on the contact state of the wheel and rail,which is more prone to multi-point contact and deteriorates the driving conditions,which leads to the continuous increase of the maintenance and repair input of the line equipment.The problems of rail wear on the red lime railway also appear on other special railway lines in our country.It is of practical significance to study the cause analysis of rail wear and the measures to reduce it.This paper mainly studies the following problems,the specific contents are as follows:(1)Simulation calculation of rail wear of the special railway line of red lime.A dynamic model of coupling C80 freight car-orbit space is established.The contact point of wheel-rail is obtained by trace method,then the contact gap and contact spot of wheel-rail are calculated;and the normal stress of wheel-rail is calculated by finite element method.(2)Using the UM to establish a three-car marshalling vehicle rail dynamic model,combined with the Archard wear model,simulation calculation of rail wear,after the wear depth of 0.1mm,the rail profile is updated and the next dynamic calculation is carried out and the model correction is carried out by comparing and analyzing with the measured wear.(3)The rail wear under different line conditions is calculated for the straight line segment,the detente curve segment and the circular curve segment under the influence of factors such as bottom slope,detente curve length and super high.The results show that the shape of wear depth is saddle with the increase of rail bottom slope from 1/40 to 1/10.Moderation line segment,when the rail bottom slope gradually increases from 1/20 to 1/10,the outer rail contact form becomes two point contact,the region becomes narrower,the rail shoulder side wear amplitude increases;the internal rail contact form is single point contact,the vertical wear amplitude does not change much;the transition curve length changes,the influence on the external rail wear is greater than the internal rail,the external rail wear amplitude decreases with the increase of the transition curve length,the internal rail first decreases and then increases.In the circular curve segment,with the increase of ultra-high,the variation ofinternal and external rail profile and the distribution of wear depth are obviously different,but the wear depth amplitude is increasing gradually.(4)The results show that when the running speed of the vehicle increases from 10 km/h to 60 km/h,the variation and depth distribution of the inner rail profile are obviously different,the vertical and and side grinding of the inner rail decrease,the lateral grinding of the outer rail increases,and the vertical grinding area develops from the inner rail shoulder to the center of the rail head,especially when the speed is 10 km/h.The mm,distribution area is rail shoulder and middle rail head,with the outer rail side at a speed of 60 km/h.the mill reaches2.24 mm,the vertical mill 0.76 mm,is significantly smaller than the internal rail wear peak at a speed of 10 km/h.when the external rail friction coefficient is 0.25,the internal rail friction coefficient decreases from 0.4 to 0.1,and the external rail wear region does not change.the internal rail wear region extends from(-12,13)mm to(-12,28)mm,but the external rail wear depth increases and the internal rail first increases and then decreases.the external rail wear variation diverges with the decrease of the internal rail friction coefficient.(5)Finally,according to the analysis,the K23+030.562~K23+902.692 of the Hong-Ning Railway Ranks,proposed adjustments.Specifically,the rail bottom slope of the transition curve segment and the circular curve segment is adjusted to 1/30,and the ultra-high adjustment of the circular curve segment is 30 mm,and the running speed is adjusted to 40km/h,and the wheel-rail friction coefficient of the straight line segment is adjusted to 0.15.The results show that the amplitude of wear depth after improvement is obviously smaller than that before improvement,the maximum wear depth of circular curve decreases by 22%,and the maximum wear depth of straight line section decreases by 8.7%.The increase of the maximum wear depth of the improved rail decreases with the increase of the transport capacity.