考虑轮轴过盈配合的地铁车轮踏面制动温度场和应力场研究

Study on Braking Temperature and Stress Fields of Metro Wheel Tread Considering Wheel-Axle Interference Fit

【目的】地铁车轮受力复杂,不仅受轮轨耦合力和轮-轴过盈配合产生的接触压力的影响,还受制动过程中产生的热载荷的影响。【方法】以某单S型辐板地铁车轮为研究对象,在ABAQUS软件中建立了地铁车轮有限元模型,分析了轮轴过盈配合对车轮在直线工况下机械应力分布的影响。建立了道岔工况下车轮踏面制动时的热-力耦合模型,采用直接耦合法研究了车轮温度场和应力场的变化规律,研究了不同磨耗量下车轮的机械应力和热-机耦合应力对车轮结构强度的影响。【结果】结果表明:制动时热载荷主要影响靠近踏面的结构部分,靠近轮毂部分受轮轴过盈配合影响大;新车轮与磨耗到限车轮辐板处的耦合应力最大相差69.3 MPa;车轮直径在820~840 mm区间内耦合应力比较稳定,浮动只有9.1 MPa.【结论】该研究为地铁车轮结构设计提供了科学的依据,对地铁车轮的维护工作具有良好的指导作用。

【Purposes】 The stress on the metro wheel is complicated, which is not only influenced by the wheel-rail coupling force and the contact pressure induced by the axle-wheel interference fit, but also by the thermal load generated during braking. 【Methods】 In this paper, a metro wheel with single S-type spoke plate is taken as the research object. The finite element model of the wheel is established in ABAQUS software and the influence of the axle-wheel interference fit is analyzed on the mechanical stress distribution of the wheel under the straight-line load condition. The thermal-mechanical coupling model of the wheel is established at tread braking under the turnout load condition. The direct coupling method is used to study the variation of the temperature and stress fields of the wheel. Effects of mechanical stress and thermal-mechanical coupling stress on the structural strength of the wheel under different wear levels are studied. 【Findings】 Results show that the thermal load mainly affects the structure near the tread, while the part near the hub is greatly affected by the interference fit. The maximum difference of coupling stress between the new wheel and the worn-to-limit wheel is up to 69.3 MPa. The coupling stress of the wheel is relatively stable within the diameter range of 820-840 mm, with a float of only 9.1 MPa. 【Conclusion】 This study provides scientific reference for the structural design of metro wheels and can give a good guidance for the maintenance work.