Hydraulic actuators are an important executive component of modern aircraft and are typically characterized by a reciprocating sealing form. Sealing failure affects the implementation of aircraft missions and flight safety. To determine the main cause for sealing failure of the ACGT-HP combined rod seal in an aircraft actuator, taking the new seal as the control group, compare and analyze the failure and non-failure combined rod seals under the same working conditions for approximately the same time. By means of microscopic examination, physical performance testing and chemical composition analysis, eight ACGT-HP seal failure reasons that act synergistically are summarized and preventive improvement measures are proposed. It is concluded that the main reason for the failure of the combined seal is that the wear of the seal is exacerbated by various inappropriate coupling factors, resulting in the rapid reduction of contact stress and seal failure. By putting forward the key points of seal design and assembly, a universal failure analysis method from macro to micro is found, which can be used for various types of combined seals to guide the design and application of the ACGT-HP seals.

液压执行器是现代飞机的重要执行部件，通常以往复式密封形式为特征。密封失效影响飞机任务的执行和飞行安全。为确定飞机执行机构ACGT-HP组合杆密封件密封失效的主要原因，以新型密封件为对照组，对相同工况下失效与未失效的杆件密封件进行对比分析，大约为同时。通过显微检查、物理性能测试和化学成分分析，总结了八种协同作用的ACGT-HP密封失效原因，并提出了预防改进措施。得出组合密封失效的主要原因是各种不适当的耦合因素加剧了密封的磨损，导致接触应力迅速降低，密封失效。通过提出密封设计和装配的关键点，找到了一种从宏观到微观的通用失效分析方法，可用于各种类型的组合密封，指导ACGT-HP密封的设计和应用。