DEVELOPMENT OF COLD-ROLLING TECHNOLOGY FO R HIGH THICKNESS ACCURACY AND EXCELLENT TENSILE PROPERTY SHEET

In order to meet customer's growing demand for thickness accuracy of c old rolled strip, it becomes more important to minimize the thickness deviation in the transverse direction as well as in the longitudinal d irection. Through our research work, it was revealed that strip edge p rofile can be controlled by changing a roll crown and the control rang e is large when a reduction in thickness is large. A Pair Cross (PC) m ill has been introduced in stands 1-3 of the new 5-stand tandem cold s trip mill at Kashima Steel Works of Sumitomo Metal Industries. Ltd. Us ing the PC rolling technology and a newly developed automatic gage con trol (AGC) system, a production system for a high thickness-uniformity sheet has been developed. Excellent tensile property sheet is also re quired recently by automobile companies. By rolling ultra-low carbon s teel with high reduction excellent tensile property has been obtained.