粗轧板坯镰刀弯控制模型的研究与应用

针对经常困扰热轧生产的粗轧板坯镰刀弯缺陷，本文结合弹跳方程和解析法，分析了引起板坯镰刀弯的主要因素——轧机两侧纵向刚度偏差、来料楔形及轧件运行走偏，分别计算了其对应的调整量，建立了基于轧机两侧轧制力差的镰刀弯调平控制模型.该模型可反映轧机两侧纵向刚度差、来料楔形及轧件运行走偏等主要因素与镰刀弯的定量关系，进而计算出控制镰刀弯的粗轧机各道次辊缝倾斜调整值.与现场实测值进行离线验证对比，实测值与计算值比值平均为0.977，结果表明镰刀弯调平模型能够预估板坯各道次辊缝倾斜调整值.将模型投入2250 mm热轧机组使用后，板坯镰刀弯弯曲量未达标率从24.88%下降到6.62%，提高了镰刀弯控制效果，使粗轧板坯镰刀弯问题得到了很大缓解. 

Study and application of the slab camber control model in rough rolling

Aimed at the frequently occurred problem of slab camber in rough rolling of hot strip mills, the main factors causing slab camber, including the difference in longitudinal stiffness of the mill on both sides, incoming wedge and running deviation of rolled pieces, were analyzed by combining with the spring equations and analytical method in this paper, and the corresponding adjustment values were respectively calculated. Based on rolling force difference on both sides, the tilting control model of slab camber was established. This model could reflect the quantitative relationship between the main factors and camber, such as the difference in longitudinal stiffness of the mill on both sides, incoming wedge and running deviation of rolled pieces, etc., and then the tilting values of roll gap for controlling camber were calculated in each pass of the rough rolling mill. Comparing with the real values by off-line verification, the averaged ratio of measured and calculated values is 0.977. The results show that the tilting values of roll gap can be estimated by the tilting control model of slab camber in each pass. Since putting the model into a 2250 mm hot strip mill, the camber values not complying with tolerance declined from 24.88% to 6.62%. By improving the control effect of camber, the slab camber problem has been greatly eased.