考虑辊缝变化的板带热轧动态理论模型  

Dynamic theoretical model of strip hot rolling considering change of roll gap

作　　者：杨彦博 彭艳 刘洋 刘才溢 王瑾 YANG Yan-bo;PENG Yan;LIU Yang;LIU Cai-yi;WANG Jin(National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,Yanshan University,Qinhuangdao 066004,Hebei,China)

机构地区：[1]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004

出　　处：《钢铁》2022年第2期85-93,共9页Iron and Steel

基　　金：国家重点研发计划资助项目(2017YFB0304103);国家自然科学基金区域创新发展联合基金重点支持资助项目(U20A20289)。

摘　　要：精准的轧制模型是生产优质带材的关键,目前常用的热轧模型仅适用于研究静态轧制过程。当面对变厚度轧制及轧机振动等动态轧制过程时,由于常用的静态模型不包含辊缝变化速度参数,因此其模型结构缺乏完整性。为了对动态轧制进行全面深入的研究,需要建立一个包含辊缝变化速度参数的动态轧制模型。基于Orowan方程,同时考虑辊缝变化速度对带材平均变形速率和变形区长度的影响,建立了动态速度场模型、平均变形率模型和力微分平衡方程,并最终求解得到动态轧制力解析解。采用二辊试验轧机开展了动态轧制试验,通过与动态热轧试验结果进行对比,动态轧制模型具有较高的精度,可为动态轧制力精准预备提供理论指导。通过分析发现,当辊缝变化速率为零时,模型与SIMS模型相同。利用上述模型分析了动态轧制过程中各工艺参数的变化规律,结果表明,动态轧制时带材出口位置偏离了两工作辊圆心的连线,偏离方向和大小直接受辊缝变化速度大小和方向的影响。相同轧制规程时,辊缝减小时轧制力大于静态轧制,而辊缝增加时轧制力小于静态轧制,这是由于变形区长度和辊缝内金属变形速率受辊缝变化速度的大小和方向影响导致的。此外,在辊缝减小时轧制力会出现随轧制速度的增加而减小的反常现象。Accurate rolling model is the key to production of high-quality strips.Currently,the commonly used hot rolling model is only suitable for studying the static rolling process.When faced with dynamic rolling processes such as variable thickness rolling and rolling mill vibration,the model structure lacks integrity since the commonly used static model does not include the roll gap change speed parameters.In order to conduct a comprehensive and in-depth study on dynamic rolling,it is necessary to establish a dynamic rolling model which includes the parameters of roll gap change speed.Based on the Orowan equation,the dynamic velocity field model,the average deformation rate model and the force differential balance equation were established while considering the influence of roll gap change speed on the average deformation rate of strip and the length of deformation zone,and the analytical solution of dynamic rolling force was finally solved.A two-high experimental rolling mill was used to carry out dynamic rolling experiments.Comparing with the results of dynamic hot rolling experiments,the dynamic rolling model had high accuracy,which could provide theoretical guidance for precise preparation of dynamic rolling forces.Through analysis,it is found that when the roll gap change rate is zero,the model in this paper is the same as SIMS model.Change law of various process parameters for the dynamic rolling process in the model above was analyzed.The results show that the strip exit position deviates from the line of two work roll centers during dynamic rolling,and the deviation direction and size are directly affected by the size and direction of roll gap change speed.Under the same rolling schedule,when the roll gap is reduced,the rolling force is greater than that of static rolling,while roll gap is increased,the rolling force is less than that of static rolling.This is because the length of deformation zone and metal deformation rate in the roll gap are affected by size and direction of roll gap change speed.In additio

关 键 词：Orowan方程 动态轧制 轧制力 应力状态系数 理论模型 

分 类 号：TG335.11[金属学及工艺—金属压力加工]