ASR work roll shifting strategy for schedule-free rolling in hot wide strip mills

Abstract

In order to meet the requirement of schedule-free rolling (SFR) for wide non-oriented electrical steel production with a large number of the same width strip rolling campaigns, ASR (asymmetry self-compensating work rolls) shifting strategies for different rolling schedules are studied. According to the actual rolling process, the work roll wear prediction mathematical model for non-oriented electrical steel sheets and a 3D finite element model for roll stacks are established. The effects of the shifting step and the shifting rhythm on the ASR wear contour and the loaded roll gap profile within the entire rolling campaign are analyzed. The reasonable ASR shifting strategies for different rolling schedules are developed. In comparison with the conventional work roll contour of K-WRS mill, the self-maintenances of roll contours for ASR reach to more than 88%, the rate of the measured strip crown less than 45 μm increased from 41.8% to 94.9%, and the rate of the measured strip crown larger than 52 μm decreased from 32.6% to 2.0% by industrial test on the production of the same strip-width for wide non-oriented electrical steel sheets in the 1700 mm hot strip mill of WISCO. The ASR technology has applied to the production successfully.