某型航空发动机压气机滚棒轴承失效故障分析

Failure Analysis for Rolling Bearing of an Aero-engine Compressor

以某型航空发动机压气机的滚棒轴承为研究对象,针对整机试验时,振动突增、膜盘联轴器连接轴断裂的问题。首先根据检验理化分析及振动数据分析的结果,确定了“滚棒轴承损坏”是导致故障的直接原因。再结合故障树对可能引起轴承损坏的各种原因进行排查,最后通过中心拉杆变形量分析、模态试验与弹支振动应力数据分析,确定“轴承预紧力偏小引起转子失稳”为故障的根本原因。揭示了故障发生的机理过程,确定了故障原因,并提出发动机装配过程中,关注中心拉杆变形量的同时还需考虑叶片盘的轴向变形,为其他型号的设计及装配提供参考。

This paper takes the roller bearing of an aero-engine compressor as the research object,and focuses on the sudden increase of vibration and the fracture of the connecting shaft of the diaphragm coupling during the whole engine test.Firstly,according to the results of physical and chemical analysis and vibration data analysis,it is determined that the“roller bearing damage”is the direct cause of the fault.Combined with the fault tree,various causes that may cause bearing damage were investigated.Finally,through the analysis of the deformation of the central tie rod,the modal test and the analysis of the vibration stress data of the elastic support,it was determined that“the small preload of the bearing causes the rotor to be unstable”is the root cause of the fault.This paper reveals the mechanism process of the fault,determines the cause of the fault,and puts forward that in the process of engine assembly,the axial deformation of the blade disk should be considered while paying attention to the deformation of the central tie rod,which provides a reference for the design and assembly of other models.