Research and application of approximate rectangular section control technology in hot strip mills

Abstract

Profile requirements of silicon steel strip are extremely high and the thickness difference of cold-rolled products is usually less than 7 lm, and the profile quality of hot-rolled strip is the key to ensure the thickness difference of cold-rolled products. In order to produce the silicon steel strip with high-precision shape, the concept of quasi-rectangular rolling during hot continuous rolling was put forward; the equipment configuration and technical method of approximate rectangular section control were studied. Through the roughing multi-target load distribution technology and the roll configuration technology for uniform wear of a 4-high rolling mill, the strip crown of transfer bar was reduced and the profile control stability was guaranteed. Configuring variable contact back-up roll technology on all stands in the finishing rolling process, equipped with symmetry variable taper work roll and long-stroke intelligent shifting strategy in the downstream stands, and using side rolling lubrication technology can make the roll wear more uniform, reduce the edge drop of silicon steel strip, improve the profile quality, and make the strip section of finishing exit ''quasi-rectangular''. In addition, induction furnace and side heater were also equipped to guarantee the temperature uniformity of the strip, so as to improve the stability of profile control. The whole control technology is based on the 1580-mm hot continuous rolling production line, designed, and developed according to the characteristics of equipment and products, and has been successfully applied, which can obtain the approximate rectangular strip section satisfying the flatness quality, and improve the strip section precision of silicon steel and other products.

Development of Cold‐Rolling Edge‐Drop Control Technology for Electrical Steel: A Review

“…[ 5 ] A research team from the University of Science and Technology Beijing proposed the approximate rectangular section control technology in hot‐rolling. [ 6 ] Moreover, a detailed summary of studies is available in the literature, focusing on finishing mill configuration, rolling schedule arrangement, roll wearing, roll cooling, special roll‐contour design, and corresponding roll‐shifting strategies.…”

Effect of strip profile of hot-rolled silicon steel on transverse thickness difference of cold-rolled strip

“…The transcription rate and the heredity coefficient are well used in the research of the heredity from crown to flatness in rolling hot strips [13]. An approximately equal proportional crown [14,15] is a famous heredity principle of the strip profile in hot rolling and is widely applied to set the strip crown at each outlet of the stand in tandem to maintain a good shape. However, with the unceasing rise in the requirements for shape quality, the heredity principle of an approximately equal proportional crown has increasingly highlighted its limitations, and some revised models have been developed.…”

Improvement of Contact Stress Distribution Between Work Roll and Backup Roll of a Hot Strip Mill

“…Rolling contact fatigue in the form of spalling may produce by uneven distribution and huge peaks of contact stress [1,2]. Strip shape is a key aspect of the steel quality, which is also affected by contact state [3,4]. In this paper, the contact stress distributions between work roll and backup roll with continuously variable crown (CVC) roll contour along the axial and radial directions are calculated.…”