针对某发动机管路支架安装边裂纹问题，通过对支架裂纹处断口的分析，及对支架组件的静强度受力分析，明确解决失效问题。从零件设计、加工、装配3方面着手，确定失效原因为支架与管路之间存在相互作用力，支架工作时除受振动应力影响外还承受装配时引入的额外应力。因支架组件刚性较强，受力后缓冲较弱，支架弹性变形所产生的作用力会传递至孔边，易产生裂纹。设计了增加浮动结构的改进方案，其具备轴向变形补偿能力，可以大幅降低传递至孔边的作用力。经试验验证，该措施可行、有效。

In response to the crack at the installation side of a certain engine pipeline bracket， the research direction for solving the failure problem was clarified through analysis of the fracture at the bracket crack and the static strength stress of the bracket components. From aspects of part design， processing and assembly， the cause of the problem was determined to be the interaction stress between the bracket and the pipeline， which made the bracket work under original vibration stress and additional stress introduced during assembly. Due to the strong rigidity of the bracket components and weak buffering under stress load， the stress generated from bracket elastic deformation would be transmitted to the hole edge， probably causing the formation of cracks. The improvement with floating structure was designed which has the ability of axial deformation compensation and can significantly reduce the stress transmission. The proposed optimization design is validated by tests.