Aiming at the problems of uneven distribution of mechanical properties of the connection interface after the actual assembly of aero-engine rotor and the fretting slip of the connection interface during service

this paper takes the combined Jeffcott rotor as the research object and comprehensively considers the distribution law of the actual bolt preload. Firstly

the mechanical analysis of the connection interface of the combined rotor under high-speed rotation is carried out

and influence mechanism of the preload on the connection interface slip is revealed. Secondly

based on the measured preload data

the finite element model of combined Jeffcott rotor is constructed to simulate the slip process of the connection interface. Finally

the influence of the mean value and dispersion of preload on the slip law of rotor interface is systematically analyzed. The results show that the mean value of preload mainly affects the amount of interface slip

but has little effect on the uniformity of slip distribution

while the dispersion of preload will significantly affect the uniformity of slip distribution. In the actual assembly process

by reducing the dispersion of bolt preload distribution

the adverse effect of interface non-uniform slip on the connection performance of combined rotor can be reduced.