.1420 Mill Rolling T5 Material Vibration Mechanism And Process Optimization

The trouble of vibration on the rolling mill is a universal problem in the field of metallurgy. Because of the long driving-chain and complex technical conditions, the causes of vibration on a mill are intricate. Hitherto, large numbers of work has been done for resolve this kind of problems, and a great deal of valued experience has been accumulated.To solve the vibration problem on the 1420 Tandem Cold mill of Bao-Steel Group, the data gathered from the spot has been studied and a conclusion has been reached: the slot between the two rollers is the source of the shake, and the decline of the friction between two rollers as result of the changed rigidity of material and increased rolling velocity is the cause of the vibration. So "string-shake" and torsion self-excitation vibration of the working rollers has been produced. Exposed to the two oscillations, the system's intense sympathetic vibration happened.In this thesis, calculation in theory has been done firstly with establishment of the vibration equation and the main frequency of the oscillation is found by studying the phenomena of the "string-shake"; then the modal of the system has been modeled, and through analyzing natures of the system and its parts by finite-element Ansys analysis, natural frequency in connection with the main vibration- frequency has been discovered. Because the frequency is very close to the testing data, the study has offered basis to solve the problem effectively.Combine the theory analysis and the study on the data received by the field test, the ultima optimize scheme has been offered. That is, by increasing the viscosity of the lubricant to augment the friction between the rollers, synchronously, adjusting the rolling force and the strip-steel's tensile force to change the frequency of the "string-shake" to keep away from the resonance-frequency. The measure proved by result of the testing is efficient and received consistent approbation.