润滑时机对地铁试验段曲线钢轨剥离掉块与磨耗影响研究

Study on Influence of Rail Lubricant Timing on Spalling Defects and Wear of Metro Test Section Curve

为探究地铁小半径曲线润滑处理时机对钢轨磨耗及剥离掉块的影响,选取两条运营条件相似的线路,其中一条线路进行润滑与停止润滑两个阶段的处理,将其称为工况1,另一条未经任何处理的线路作为对比工况,称为工况2。分别对2个工况现场进行跟踪观测,并对观测结果进行对比分析。研究发现:在进行了润滑处理的后期运营期间,2个工况的钢轨侧磨都在正常增长值内,润滑处理在新轨下道前期对钢轨侧磨影响不大,主要对其轨距角与轨顶磨耗有抑制影响。对比工况2可以发现,工况1在润滑阶段早期出现了大面积的剥离掉块现象,这是由于早期润滑导致的“油楔效应”加速了疲劳裂纹的发展,最终造成曲线段上大面积的剥离掉块。通过研究获得的地铁曲线合理润滑时机与周期,可为地铁公司运营维护提供理论基础。

In order to explore the effect of lubrication timing on rail wear and spalling defects in the metro sharp curve, two lines with similar operation conditions are selected. One line carries out treatment of the two stages of lubrication and stop lubrication, as in Case 1. The other line, as in Case 2, is without any treatment and used for comparison condition. Both working condition sites are tracked, observed and comparatively analyzed. Research results show that: in the later stage of the lubrication treatment, the rail side wear amount of the 2 cases is within the normal growth range, and the lubrication treatment has little effect on the rail side wear in the early stage of the rail operation, and mainly suppressed the rail gauge corner and the wear of the rail top. However, compared to Case 2, Case 1 has a large area of spalling defects at early stage due to the ‘oil wedge effect’ caused by early lubrication accelerating the development of fatigue cracks, and finally causes large-area spalling defects on the curve segment. The reasonable lubrication timing and cycle of metro curve is obtained from research, providing theoretical basis for metro company operation and maintenance.