Abstract: In order to analyze and improve the local cracking of the welding seam of the air conditioning support of a domestic off-road vehicle during the high-altitude drop impact test, this paper establishes the model of the air conditioning support and the welding seam of an off-road vehicle with UG three-dimensional software, and uses Ansys Workbench software to analyze and predict the welding seam strength of the air conditioning support during the high-altitude drop impact test. The possible parts of weld failure are found out, a design idea of capping stiffeners is proposed and the structure of local joints is optimized and improved. The analysis results show that the local stress of the improved weld is reduced by 49.9%～71.5% in the drop test, and the safety factor is significantly improved, which will increase the reliability and service life of the support, and the improvement measures are effective through physical verification.

Key words: Off-road vehicles; Drop impact; Weld failure analysis; Ansys Workbench

摘要： 为分析和改进国内某越野车在进行高空跌落冲击试验时，空调支架焊缝局部开裂问题， 文章用 UG 三维软件建立了某越野车空调支架及焊缝模型，采用 Ansys Workbench 软件受力 分析预测了车辆高空跌落冲击过程中空调支架的焊缝强度，找出了焊缝可能失效的部位，提 出一种封顶式加强筋设计思路并对其局部焊脚结构进行了优化改进。分析结果表明，改进后 的焊缝在跌落试验中局部的应力减小 49.9%～71.5%，安全系数显著提升，将增大该支架的可 靠性和使用寿命，并经实物验证改进措施有效。

关键词: 越野车；跌落冲击；焊缝失效分析；Ansys Workbench