某V型发动机主轴承座结构分析及优化

齐晓慧，纪雷*，赵宝新，秦少博，刘丽佳

长城汽车股份有限公司河北省车用发动机技术创新中心（筹），河北 保定  071000

摘要：为解决某V型发动机在可靠性试验中出现的主轴承座壁面断裂问题，采用计算机辅助工程仿真分析断裂部位强度，开展金属材料失效分析和生产过程排查，明确断裂原因，制定改进方案，并对优化后的样件进行可靠性试验。结果表明：曲轴箱通风口附近主轴承座壁面高周疲劳安全系数达到临界值及样件铸造缺陷是造成断裂的主要原因；经可靠性试验验证，优化后的主轴承座再未发生断裂。改进曲轴箱通风口位置和形状、优化铸造工艺、将通风口由铸造成型改为机械加工成型等措施，可以有效解决主轴承座结构失效问题。

关键词：V型发动机；主轴承座；高周疲劳安全系数；可靠性试验

Structural analysis and optimization of main bearing seat of V-type engine

QI Xiaohui, JI Lei*, ZHAO Baoxin, QIN Shaobo, LIU Lijia

Great Wall Motor Co., Ltd., Hebei Automotive Engine Technology Innovation Center(under preparation),Baoding  071000, China

Abstract：In order to solve the main bearing seat wall fracture problem of a V-type engine in the reliability test, the computer-aided engineering simulation is used to analyze the strength of the fracture site, metal material failure analysis and production process troubleshooting, the fracture is identified, improved and validated. The results show that the high cycle fatigue safety factor of the main bearing seat wall near the crankcase vent reaches the critical value and the casting defects of the sample are the main reasons for the fracture. It is verified by reliability test that the optimized main bearing seat is not fracture again. Improving the position and shape of the crankcase vent, optimizing the casting process, changing the vent from casting to mechanical processing, and other measures are implemented, which can effectively solve the main bearing seat structural failure problem.

Keywords:V-type engine; main bearing seat; high cycle fatigue safety factor; reliability test