Sealing Performance and Vibration Response of Clamp-Based Rapid Repair for Damaged Thin-Walled Aviation Fuel Pipelines

Rapid repair of damaged thin-walled aviation fuel pipelines requires not only reliable sealing but also sufficient structural safety under both static preload and vibration. In this study, a clamp-rubber liner repair structure was investigated using finite element analysis and airtightness experiments. A three-dimensional nonlinear finite element model incorporating a Mooney–Rivlin hyperelastic rubber model, contact nonlinearity, and pipe structural response was established. The effects of preload displacement, rubber hardness, clamp width, and installation angle on sealing performance were evaluated in terms of contact pressure distribution, sealing-band continuity, and Von Mises stress. Prestressed modal and frequency-response analyses were further conducted to investigate vibration-induced changes in sealing and structural responses. The results show that increasing preload displacement improves interfacial contact and promotes the formation of a continuous sealing band, but excessive preload markedly increases the local stress of the thin-walled pipe. Higher rubber hardness and larger clamp width generally enhance sealing performance, although both may reduce the structural safety margin of the pipe. Increasing the installation angle deteriorates interfacial contact, with the 90°configuration exhibiting a pronounced risk of persistent leakage. Under fundamental-frequency vibration, the average contact pressure decreased by up to 10.06%, whereas the maximum pipe Von Mises stress increased by up to 20.06%. Airtightness pressure-holding tests at 0.3 MPa showed trends consistent with the numerical predictions. These results demonstrate that sealing reliability and pipe structural safety must be considered simultaneously when selecting repair parameters for thin-walled aviation fuel pipelines.