Abstract:

For study the vibration of CSP mill of thin slab continuous casting and rolling mill when it roll high strength thin strip, the on-line monitoring system is used to obtain the vibration signal. Through signal analysis the coupling vibration exist in the electric drive, mechanical drive and the screw down system of CSP rolling mill, and it present nonlinear harmonic characteristics. The torsional vibration appearing on main drive of F3 rolling mill is regarded as the research object. By building the equivalent nonlinear two-DOF model, then, as external disturbance excitation, the harmonics of electromagnetic torque and rolling force are applied on the model. The solving result is that the polymorphism characteristics including ultraharmonic, subharmonic, and combination resonance are displayed on main drive system under multi-source excitation. For the case of combination resonance “”, the simulation show that vibration amplitude increases with the reduction of the one-time or three-times damping and the increase of three-times stiffness, initial load and harmonic excitation. Thus the project is implemented to suppress the torsional vibration by use of inhibition of harmonic excitation of electric drive and rolling force. The vibration amplitude value reduce 75% of the original and good results are obtained. This research can provide reference for vibration suppression, deep understanding of nonlinear dynamic characteristics and coupling vibration mechanism in rolling mill.

Key words: creep resistance, creep stress exponent, nanoindentation, micro solder joint