动车组车轮辋裂损伤容限和剩余寿命评估

Damage Tolerance and Remain Fatigue Life Evaluation of Shattered Rim of EMU Wheels

针对我国某型动车组车轮在实际线路发生的辋裂损伤,在全面失效分析的基础上,揭示了车轮辋裂失效机理;以车轮材料裂纹扩展试验数据为基础,结合Franc3D仿真分析软件对车轮内部缺陷进行裂纹扩展仿真计算.仿真结果表明:车轮内部缺陷尺寸及分布均对车轮滚动接触疲劳寿命产生影响,缺陷尺寸越大,分布位置距车轮最大应力区越近,车轮疲劳寿命越短.该车轮的损伤容限为3 mm,与标准中失效判据3 mm一致,给出了目前我国铁路车轮辋裂失效探伤标准(?3 mm横孔当量大小)的理论依据.

Aiming at the shattered rim crack damage of a certain type of Chinese EMU in the actual line, the failure mechanism of the shattered rim of EMU wheels was revealed on the basis of comprehensive failure analysis. Based on the test data of wheel materials’ crack propagation, combined with Franc3 D simulation analysis software, the crack propagation simulation calculation was carried out for the defect. The simulation results showed that both the size and distribution of the internal defects of the wheel have an impact on the rolling contact fatigue life of the wheel. The larger the defect size, the closer the distribution position is to the maximum stress area of the wheel, and the shorter the wheel’s fatigue life. The damage tolerance of the wheel is 3 mm, which is consistent with the failure criterion of 3 mm in the standard. The theoretical basis of the current standard(the equivalent size of a ?3 mm transverse hole)for detecting the crack failure of railway wheel rim in China is given.