In view of the clamp-pipe system in aero-engine

the linear stiffness and angular stiffness of clamps with diameter of 8 mm was obtained based on self-designed experimental rig. The clamp was discretized into several springs according to the experimental results

and a dynamic model of the clamp-pipe system was proposed based on the finite element method. The measured stiffness of clamps and the finite element model was verified by comparing with the measured and simulated natural frequencies and corresponding frequency response functions. Furthermore

the effect of tightening torque on the natural frequencies of the clamp-pipe system was studied. The results show that the natural frequencies of the pipe increase with the tightening torque. For the clamps studied

the natural frequencies of the pipe gradually become stable value when the tightening torque is greater than 8 N·m.