轮辋厚度对货车车轮辐板孔裂纹萌生时间的影响研究

Study on Influence of Wheel Rim Thickness on Cracking Time for Wagon Wheel Web Hole

车轮温度和应力的分布对车轮寿命有重大影响。分析轮辋厚度与车轮使用年限、辐板孔裂纹率的关系。采用有限元法模拟长大坡道制动热应力和轮轨机械应力随轮辋厚度变化的规律,建立考虑轮辋厚度的辐板孔裂纹萌生时间预测模型。结果表明:坡道制动工况与机械载荷工况的组合作用是车轮辐板孔边产生高应力的主要因素;车轮辐板孔应力随轮辋厚度的减小而增大;机械应力与热应力叠加是导致辐板孔裂纹萌生的主要原因。预测的疲劳裂纹萌生时间与实际情况比较接近。

The distribution of wheel temperature and stress affects the wheel service life greatly. The article analyses the relationship between wheel rim thickness and wheel service life and wheel web hole cracking rate. It applies the fi- nile element method to simulate the rules for which the thermal stress of long steep grade braking and the mechanical stress of wheel track change with the wheel rim thickness, establishing a model forecasting the wheel web hole crack- ing time, with the wheel rim thickness considered. The results indicate that ： the composite action of grade braking and mechanical load is the key fac.tor for a wheel web hole to produce a high stress; the wheel web hole stress in- creases as the wheel rim thickness decreases; the superposition of mechanical stress and thermal stress is the main reason for wheel web hole cracking. The fatigue cracking time predicted is close to the actual conditions.