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The turbine disk-drum is one of the key components of an aero-engine and its assembly is connected with high-strength refined screws. But due to the uncoordinated rotation and deformation, the screws have abnormal wear damage. Through detailed contact stress analysis of screw body and component level using the finite element method, combined with experimental observation, the mechanism of wear damage of screw surface in screws is determined. It mainly includes the following: Firstly, the finite element method is used to calculate the deformation and stress distribution of the connecting screw of the turbine disk-drum assembly. Then, after the overspeed test, the morphology of the screws disassembled from the disk-drum assembly is evaluated. It was found that the wear degree in the circumferential direction and axial direction of the screw was quite different, that is, the screw wear experiment was consistent with the finite element analysis results. Finally, the influence of different rotation states and screw tightening states on screw wear was compared and analyzed. Conclusions obtained in this paper will be helpful to improve the assembly reliability of turbine drum.

The drum rotor of an aero-engine is connected by one or multiple mounting edges through bolts, and their dynamics are significantly influenced by the preload state of the bolts. Long working hours in challenging environments can result in the deterioration of bolt pre-tightening during assembly or service, which impacts the rotor’s dynamic stability and overall performance. Currently, there are no available methods for detecting the dynamic characteristics of the drum connection components. This paper analyzes the impact of the natural characteristics of the drum composite structure of a high-pressure aero-engine turbine based on the refined finite element method when the preloading state changes. Two conditions of deviation and uneven stiffness distribution were applied to the connected components of the drum. The analysis focused on the impact of the pre-tightening state on its natural frequency. After analyzing the feasibility of identifying the pre-tightening state, two methods are proposed. These methods focus on changes in natural frequency and mode shape, specifically the sensitive natural frequency change method and the mode step change method. The methods proposed in this paper can serve as a reference for evaluating the quality of assembling complex disc–drum structures with multiple bolt connections.