Possibilities for improvement of technology and equipment for continuous hot rolling of steel strips

Abstract

The properties of metal rolled in continuous wide strip hot rolling mills are not currently being fully utilized to achieve the desired structure. By employing the austenite recrystallization diagram of steel, which is based on the findings of physical modeling and quantitative metallographic analysis regarding the distribution of relative compression on stands of the continuous finishing train of the mill, it is possible to obtain finished strips with minimal grain diversity. In the transition from the conditions of rolling a narrow model sample to the actual conditions of rolling a wide strip with tension, it is essential to consider the correction of the crushing coefficient of recrystallized austenite grains in accordance with the stress-strain state of the metal. To limit the growth of austenite grains subsequent to the initial compression in the continuous finishing train of the mill, instead of the initial two four-roll stands, it is proposed that a novel technical solution be implemented: a double-four sheet-rolling stand. In order to optimize the quality of the hot-rolled edges of finished strips, it is recommended that the vertical rolls be positioned behind the double-four stand in the finishing train.