【作者】 肖铁汉一；

【导师】 金新灿；

【作者基本信息】 北京交通大学 ， 车辆工程， 2011， 硕士

【摘要】 车轴是保障动车组行车安全的关键部件。随着时速达到380公里的CRH380AL系列动车组的研制成功,高速运行下车轴承受的交变载荷得到加剧。同时,由于轮轴压装部位存在微动损伤,在随机载荷的长期作用下逐渐积累,到达一定程度引起疲劳断裂,严重危及行车安全。本文以CRH380AL动车车轴为研究对像,采用线路动应力实测和有限元方法研究车轴载荷谱及压装部位的损伤,主要内容如下：1、提出车轴动应力实验布片方案及组桥方式。采用准静态法对车轴进行载荷识别,利用有限元前处理软件Hypermesh及有限元分析软件Ansys计算分析动车轮对有限元模,得到测点的载荷应力传递系数。2、在京沪线分区段进行动应力线路实测并对数据进行处理。通过载荷识别将动应力时间历程转换成载荷时间历程,编制不同速度级下的载荷谱。3、从车轴受载角度出发,简化分析载荷对轮轴压装部位损伤的影响。4、基于标准计算得到车轴压装部位的名义应力谱,按照等损伤原则获得安全运行1200万公里的等效应力幅,标准对轮轴压装部位疲劳极限的规定,通过等效应力幅与疲劳极限的对比结果,对轮轴压装部位的损伤进行分析。5、从车轴的尺寸角度出发,探讨了如何减小轮轴压装部位微动损伤的措施和方法。更多还原

【Abstract】 The train axle is the key component of the Electric Motor Unit (EMU). With the successful development of the CRH380AL in China, the alternating load on bearings becomes more and more serious by the speed of 380km/h. At the same time, due to accumulated fretting damage on the axle press-fit parts, fatigue fracture may happen during the operation of the EMU, leading to severe accidents and economic loss.This paper researches on the load spectrum of the axles and damage on the axle press-fit parts, using the dynamic strain measurement and Finite Element Method (FEM).The approaches of the paper are stated as follows:1. The approaches to fixing up the strain gauges and arranging the bridge are proposed in this paper. Hypermesh and Ansys are used to analyze the model of wheel set. Then the load-strain transfer coefficient can be obtained by the load of the measuring points.2. We process the dynamic stress data derived from the intervals on the Beijing-Shanghai Highspeed Railway.The time history of the dynamic strain is transformed into the time history of the load by load identification. According to the previous research, load spectrums at the different speeds are shown in the paper.3. We analyze the relation between the load and the damage on the axle press-fit parts according to the load on the axles.4. With the principle of equivalent damage,we obtain the equivalent stress amplitude of 12 million km by stress spectrum with the different methods.According to the manufacturer’s standards and regulations for fatigue limit of axle press-fit parts, we compare equivalent stress amplitude with fatigue limit to analyze the damage on the axle press-fit parts.5. From the perspective of axle size,we discuss measures and methods that how to reduce the fretting damage of axle press-fit parts measures and methods.更多还原