二十辊轧机支撑辊组变形及板形调控分析

Analysis on flatness about support axle group deformation in 20-high mill

板带材的产能和质量是一个国家工业水平发展的重要标志,铜板带材的生产能力和地位更加显著。森德威二十辊轧机是冷轧铜板带材轧制生产的关键设备,其最外层A、D支撑辊组的弯曲变形是最重要的板形调整手段之一。支撑辊组鞍座位移变化可以使支撑辊芯轴发生弯曲变形,变形会反映到背衬轴承上并且向下依次传递给中间辊和工作辊,最终影响板厚和板形。传统的假设折线法和超静定梁法将芯轴和背衬轴承考虑为一个整体,而忽略了两者之间的变形对整体支撑辊组变形的影响。因此,基于有限元方法进行仿真拟合各段背衬轴承弯曲变形得到简化后的一次函数表达式,将各段背衬轴承拟合结果汇总进而得到整体的支撑辊组弯曲变形的线性表达式,再结合辊系弹性变形模型和金属塑性变形模型构成的板形预报模型评估支撑辊组变形程度对板形和板厚的影响。研究结果表明,对上辊系中的4个鞍座施加不同的位移组合之后,板厚和板形分布在整个板宽方向上并非局部变化,而是呈现整体的变化趋势,且4个鞍座对板形和板厚的调整效果并不相同;在施加同样的鞍座位移条件下,中部鞍座比边部鞍座对板形和板厚的影响效果更加显著,并且即使在支撑辊组中心两侧施加对称的鞍座位移,其对板厚和板形的影响也是非对称的。

The capacity and quality of sheet and strip is a momentous mark of the industrial development level,especially the copper strip.SUNDWIG 20-high mill is the key equipment for cold rolling of copper sheet and strip.The bending deformation of its outermost A and D support axle group is one of the most important means to affect the flatness.The change of the saddle displacement can bend the core shaft of the support axles,the deformation will be reflected on the support roller and transferred to the intermediate rolls and the work roll in turn,and ultimately affect the plate thickness and flatness.The traditional calculation method of support axle group deformation such as hypothetical broken line method and statically indeterminate beam method which considers the support axle and support roller as a whole,but the influence of the deformation between them on the support axle group deformation deformation is ignored.The bending deformation of each section of the support roller based on the finite element method was simulated and fitted to obtain the bending deformation of the whole support axle group,and then evaluated the influence of the deformation on the plate flatness with the flatness prediction model based on the elastic deformation model of roll system and the metal plastic deformation model.The results show that the thickness and flatness distribution doesn′t change locally but in the total width direction after applying different displacement combinations to four saddles in the upper roll system.Four saddles have different adjustment effects on shape and thickness.With the same displacement applied,the influence of the middle saddle on the flatness and thickness is greater than that of the side saddle.In addition,even if symmetrical saddle shift are applied in the saddle of the upper roll system,the influence on the thickness and flatness is asymmetric.