摘要
发动机厂内试车过程中出现金属屑报警,停车分解检查发现轴承外圈凸台断裂。采用目视和体视显微镜对轴承外圈及配合该弹支进行外观观察和痕迹分析,采用扫描电镜对断口进行分析,检查外圈材质组织和硬度。结果表明:轴承外圈凸台断裂性质为疲劳,导致轴承外圈凸台出现疲劳断裂是由于凸台和弹支卡槽配合尺寸及形状不当,导致装配时干涉。通过加大卡槽深度,采取卡槽不倒角、轴承外圈凸台倒角的结构方式,避免出现装配干涉,预防此类故障。
There was a metal filing alarm during the test run of engine,and the lug boss of the No.4 bearing outer ring was found fractured after the overhaul.Visual observation and the stereoscopic microscope were used to analyze the appearance and marks of the bearing outer ring,the scanning electron microscope was used to analyze the fracture,the material structure and the hardness of the outer ring were examined.The results show that the fracture property of the lug boss of the No.4 bearing outer ring is fatigue.The fatigue fracture is due to the assembly interference,which caused by the improper size and shape coordination between lug boss and reef groove.This kind of failures can be prevented by increasing the depth of groove,and chamfering the lug boss of the bearing outer ring instead of groove,which avoid the assembly interference.
作者
刘丽玉
金向明
高翔宇
刘昌奎
LIU Li-yu;JIN Xiang-ming;GAO Xiang-yu;LIU Chang-kui(AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;Failure Analysis Center of Aviation Industry Corporation of China,Beijing 100095,China;Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation,Beijing 100095,China;Aviation Key Laboratory of Science and Technology on Materials Testing and Evaluation,Beijing 100095,China;Key Laboratory of Science and Technology on Aeronautical Materials Testing and Evaluation,Aero engine corporation of China,Beijing 100095,China;AECC Hunan Powerplant Research Institute,Hunan Zhuzhou 412002,China)
出处
《失效分析与预防》
2020年第5期332-336,共5页
Failure Analysis and Prevention
关键词
轴承外圈凸台
Cr4Mo4V
疲劳断裂
配合尺寸
装配干涉
lug boss of bearing outer ring
Cr4Mo4V
fatigue fracture
size coordination
assembly interference
