Investigation of the cause of the chatter and physical behavior of a work roll in compact endless rolling

Abstract

Mechanical devices that contain many rotating elements such as rolling mills inevitably generate vibrations. Vibrations not only cause unnecessary loads but also affect the quality of the manufactured product. Therefore, it is important to identify the causes of vibration in such mechanical devices and control them appropriately. In this study, the various causes of vibration in a rolling process were investigated, and the vibration types present in a compact endless-rolling mill (CEM) process were analyzed and compared. Three typical causes of vibration were analyzed. Based on these results, the cause of the vibrations that occur during changes in the processing conditions in a CEM can be inferred. More specifically, numerical analysis was conducted to study the physical behavior of work rolls (WRs) according to changes in the rolling process conditions. Using these analysis results, a mechanism to produce vibrations similar to those occurring in a CEM was proposed. The results of tracking the center position of a work roll showed that the direct effects of contact pressure on vibration were minimal, and changes in the lubrication type for the physical interaction between a WR and the contact strip were identified as a cause of vibration.