Causes Analysis and Related Prevention Measures of Longitudinal Strip Peeling and Falling of Curve Rail with Small Radius
In response to the phenomenon of steel rail peeling and falling on a curve with a radius of 600 m on a conventional railway,the surface morphology of the rail peeling and falling,changes in profile at different positions,wear,hardness,crack propagation behavior,etc.were detected and analyzed to study the causes of the disease and prevention and control measures were proposed.The results show that the matrix structure,hardness,decarburization layer,and non-metallic inclusions of U71MnH rail could meet the standard requirements.The hardness of the steel rail significantly increases from the non working edge to the track gauge angle direction,resulting in a noticeable plastic deformation layer.Under the repeated action of excessive contact stress,fatigue cracks are prone to appear on the surface of the rail.After the cracks propagate to a certain extent,they bifurcate and deflect,resulting in peeling,falling and damage.This defect mainly occurs at the junction of the fish scale pattern at the gauge angle and the longitudinal crack on the top surface of the rail.It is recommended to polish the steel rails in this section to eliminate surface defects and improve the wheel rail matching relationship.Due to the simultaneous occurrence of wear and fatigue damage during wheel rail contact,there is a competitive relationship between these two.Although lubrication can reduce wear,it may exacerbate fatigue damage.Therefore,choosing the appropriate lubrication timing is crucial.
railU71MnHexperimental researchfatiguepeeling and fallingwearlubrication timing
万方数据
维普
