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Investigation of Unbalanced Mass of a Work Roll in a Cold Rolling Mill

냉간 압연기에서 작업롤의 질량 불평형에 관한 연구

  • Kim, Young-Deuk (Dept. of Mechanical Engineering, Pohang University of Science and Technology (POSTECH)) ;
  • Kim, Chang-Wan (School of Mechanical Engineering, Konkuk Univ.) ;
  • Park, Hyun-Chul (Dept. of Mechanical Engineering, Pohang University of Science and Technology (POSTECH))
  • 김영득 (포항공과대학교 기계공학과) ;
  • 김창완 (건국대학교 기계설계학과) ;
  • 박현철 (포항공과대학교 기계공학과)
  • Received : 2011.10.18
  • Accepted : 2012.01.26
  • Published : 2012.04.01

Abstract

An abrasion due to continuous friction between a work roll and strip causes the mass of the work roll to be unbalanced in the rolling process. We developed a mathematical model for the rolling mill considering the unbalanced mass and verified the model experimentally. The work roll was approximated as a rigid rotor with eccentricity, and the effect of the unbalanced mass on chatter vibration was investigated. The joint forces computed by quasistatic analysis were applied to the work roll in the rolling mill. Transient responses were obtained, and frequency analysis was performed by solving equations of motion using a direct integration method. Horizontal vibrations were more strongly affected by eccentricity than vertical vibrations. In the horizontal direction, a small eccentricity of 1% of the work roll radius considerably increased the amplitude of the chatter frequency.

Keywords

Cold Rolling Mill;Mathematical Model;Unbalanced Mass;Chatter Vibration

Acknowledgement

Supported by : POSCO 기술연구소, 한국연구재단

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