Vibration-assisted interference fit of hole–shaft assemblies via micro-crawling feed

Purpose Interference fit is a widely adopted technique in mechanical manufacturing owing to its simplicity and high reliability, and it also shows great application potential in the aerospace industry. Most existing studies concentrate on reducing assembly resistance and improving the bonding strength after fitting, yet little effort has been devoted to enhancing the accuracy of fitting displacement. In conventional manufacturing processes, system stiffness and self-excited vibration commonly lead to crawling behaviour, which seriously compromises displacement precision and may even cause process failure. This research aims to address this issue by proposing a vibration-assisted pressing method to improve the displacement accuracy of interference fit assembly. Design/methodology/approach This paper carries out a comprehensive investigation into vibration-assisted pressing for interference fit. The mechanism of using crawling characteristics to optimise displacement control is clarified, and a targeted feed control strategy is developed for the proposed vibration-assisted pressing technique. Findings The penetration effect of acoustic waves can induce stress relaxation on contact surfaces and generate controllable micro-crawling of interference-fit components. Fine regulation of such incremental crawling enables precise control over press-fit displacement, which substantially improves the overall manufacturing accuracy. Originality/value Unlike prior research that focuses on fitting resistance and post-assembly bonding performance, this work takes displacement precision as the core research objective. It reveals the intrinsic relationship between micro-crawling and displacement control in interference fit operations, and validates the effectiveness of vibration-assisted pressing for high-precision assembly. The outcomes offer a novel technical approach for high-accuracy interference fit manufacturing.