基于“3σ”准则的汽车驱动桥壳可靠度有限元分析与优化

Finite Element Analysis and Optimization of Reliability for Vehicle Driving Axle Housing Based on 3σ-rule

运用Patran和Hypermesh软件建立了某重型商用汽车驱动桥壳的有限元模型,在详细分析接触等效应力和法向接触应力的基础上,得到了驱动桥壳和半轴套管的安全配合过盈量区间。在此基础上,依据优先配合原则,对桥壳的配合尺寸公差重新做了设计,并根据3σ准则,对过盈配合公差改进前后的配合可靠度进行了计算,计算结果表明,公差改进后过盈量的分布密度服从正态分布且可靠度有比较明显的改善。

The finite element model of heavy commercial vehicle drive axle housing was established by using Patran and Hypermesh software. Based on studying the contact equivalent stress and normal contact stress, the valid interference closure range of the driving axle housing and half axle tube were obtained. On this basis, according to the principles of tolerance first, the dimension tolerance of the driving axle housing was redesigned. And then, according to the 3σ-rule, the reliability of the driving axle housing under the original tolerance fit and improved tolerance fit was computed in detail, and the result indicated that the shrink range distribution density curve showed normal distribution and the reliability had been improved clearly.