840D货车车轮辐板孔疲劳裂纹研究

根据840D车轮辐板孔裂纹调查统计数据，运用跟踪观测试验、轮轨机械载荷和制动热负载下的应力及裂纹强度因子仿真计算等结果，对裂纹成因、扩展规律及容限尺寸进行了综合分析．指出坡道制动产生的长时、稳态热拉应力与轮轨机械波动应力的综合作用是导致裂纹形成和扩展的主要因素，车轮踏面磨耗、辐板孔位偏向轮辋均将降低裂纹形成和扩展寿命．

Study on Fatigue Crack of 840D Freight Car Wheel Web Hole

Based on the investigated and statistical data from the 840D wheel web hole crack,the observation test result during the wheel operation,the simulation results of the stress and the stress intensity factor under mechanical and brake thermal load condition,this article made a comprehensive study of the crack initiation cause,the propagation law and the tolerance size.The results show that the effect of the long-time steady stress caused during grade braking and the mechanical fluctuated stress is the main factor leading to crack initiation and propagation.The wheel tread wear and the offset of the web hole both reduced the initiation life and the propagation life.