某发动机压气机前轴承剥落原因分析与改进

Analysis and Improvement on Spalling of Front Bearing on an Engine Compressor

针对某发动机压气机前支点轴承持久试车时出现剥落的问题,对失效轴承进行分析,确定轴承的失效模式为表面起源型疲劳。通过对轴承润滑环境的分析,确定导致轴承失效的主要原因是机匣内部油路残留砂粒随润滑油进入轴承内部,对滚动表面造成损伤,导致局部出现应力集中,使轴承抗疲劳能力显著下降。对机匣进行钢球振动抛磨清砂,有效清理了机匣内部油路残留物,并在发动机上通过了任务化持久试车考核验证。

Aimed at spalling of a bearing on front pivot of an engine compressor during durable trial run, the failure bearing is analyzed. The failure mode of the bearing is determined as surface initiated fatigue. Through analysis of lubricating environment of the bearing, the main failure reason is determined. The sands remaining on oil circuit inside casing enter into the bearing with oil, which causes damage to rolling surface. The local stress concentration is occurred, and the fatigue resistance of the bearing is decreased significantly. The cleaning process for sands is carried out on casing by polishing and grinding with steel ball vibration. The residues on oil circuit inside casing are cleaned up effectively, and the assessment and verification of task-based durability trial run on engine is passed.