飞机起落架作动筒密封圈失效分析

Failure Analysis on Seal Ring of Action Cylinder for Undercarriage in an Airplane

本文对飞机起落架作动筒进行了外观检查、痕迹分析,对其活塞上安装的断裂密封圈进行了物理性能测试、宏观分析、断口微观分析以及模拟验证试验等。经过综合分析认为,起落架作动筒活塞上安装的两个密封圈均发生了断裂,密封圈上的橡胶出现了掉碎块情况,使两个油箱体之间发生了串油现象,导致起落架作动筒动作失常;密封圈经油浸泡后的过量溶胀是导致其磨损疲劳失效的根本原因。

In this paper, the action cylinder of undercarriage was analyzed through the visual inspection and trace analysis, the fractured seal ring on the piston was analyzed through the physical properties test, macro and micro analysis and simulate verify test. The results indicate that two seal ring on the piston both fractured, cracked part from the rubber of the seal ring, the string oil between in the two gasoline tank led to the action cylinder of undercarriage out of gear. The action cylinder of undercarriage failure was abrasion fatigue mainly due to the seal ring excess swelling after oil immersion.