Strip shape control capability of hot wide strip rolling mills

The elasticity deformation of rolls was analyzed by means of two-dimensional finite element method （FEM） with variable thickness. Three typical mills were used as objects for analysis. A thorough study was done on the control capabilities of these mills on the strip shape. Then the strip shape control capabilities of the three mills was compared synthetically. 2008 University of Science and Technology Beijing. All rights reserved.

Research and Development Trend of Shape Control for Cold Rolling Strip

Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain can help to seek new breakthrough directions. In the past 10 years, researches and applications of shape control models, shape control means, shape detection technology, and shape con- trol system have achieved significant progress. In the aspect of shape control models, the researches in the past improve the accuracy, speed and robustness of the models. The intelligentization of shape control models should be strengthened in the future. In the aspect of the shape control means, the researches in the past focus on the roll opti- mization, mill type selection, process optimization, local strip shape control, edge drop control, and so on. In the future, more attention should be paid to the coordination control of both strip shape and other quality indexes, and the refinement of control objective should be strengthened. In the aspects of shape detection technology and shape control system, some new types of shape detection meters and shape control systems are developed and have successfully indus- trial applications. In the future, the standardization of shape detection technology and shape control system should be promoted to solve the problem of compatibility. In general,the four expected development trends of shape control for cold roiling strip in the future are intelligentization, coordi- nation, refinement, and standardization. The proposed research provides new breakthrough directions for improv- ing shape quality.

Establishment Method of Shape Standard Curve Based on Stepwise Optimization and Its Compensation Models

There are very few researches on the shape standard curve currently,and they merely remain on the level of description of the general concept and production experiences,lacking of the in-depth theoretical analysis,and the concrete principle,method and steps for determining the shape standard curve are not put forward,therefore,they are not applicable in industrial production.This is the weakest spot in the research on the basic shape theory.In this paper,the basic shape standard curve and the transverse distribution curve of the exit thickness are attained with stepwise optimization,which is based on the theoretical calculation method of the shape standard curve of strip mills proposed by authors.By calculating the shape discrimination model and the shape forecast model separately,the simultaneous iterative calculation by the previous method is avoided,and the speed and stability of calculation are improved.The compensation models of the transverse temperature difference of the strip,the shape detection roller deflection and the shape of the strip coil are established,respectively,meantime,the basic shape standard curves are compensated,and the relatively perfect theoretical establishment method of the shape standard curve is formed.The simulation and calculation are done on a 1 220 mm five-stand cold strip tandem mill.The simulation and calculation result shows that the principle,method and steps for determining the shape standard curve are correct and feasible,and the correctness of theoretical analysis and calculation is verified.This paper proposes an idea and a method for the establishment of the shape standard curve in the rolling processes of cold strip mills,which develop the theory and model of the shape standard curve and improve the quality and efficiency of the shape control in the rolling processes of cold strip mills.

适用于CSP热轧的板形模型自学习算法

自学习算法利用实测数据对模型进行修正,是高精度控制模型不可缺少的部分。针对CSP热轧生产特点改进原有板形自学习算法,提出结合同档、跨档取用的短期自学习算法和考虑不同轧辊状态的长期自学习算法。新算法综合利用一个轧制单元中的误差信息进行学习,从而预先修正板形误差。新算法在交替轧制、规格变化、换辊后首块轧制等板形控制上有明显优势,提升了头部板形精度和全长命中率。

U型板带连续挤压扩展成形力学模型

以TLJ630连续挤压机生产的U型板带为模型,将腔体和模具区的金属切分为6个切块,利用上限法建立每个切块的动可容速度场,求得每个切块塑性变形所消耗的功率、速度间断面产生的剪切功率和沿边界面的摩擦造成的功率,将6个切块的功率求和得到U型板带连续挤压扩展成形中的总功率,最终得到腔体入口的挤压应力。结果表明,随着腔体扩展角α_(1)和模具挤压角α_(3)的增大,腔体入口挤压应力先减小后增大,α_(1)的最佳区间为33°~39°;腔体入口挤压应力与腔体扩展通道长度H_(2)成反比而与模具挤压通道长度H_(3)成正比,模具挤压通道的极限长度H_(3)为57 mm;腔体入口挤压应力随着U型板带外径尺寸R_(2)和直边段长度L 10的增加而增加;U型铜排的极限尺寸为外径R_(2)=132 mm,直边段长度L_(10)=160 mm,U型板带总长为712 mm,厚度14 mm时,对应腔体入口的挤压应力达到极限p^(k)=1050 MPa。最后通过工程试验对理论计算结果进行了验证。

Development and Experimental Evaluation of Strip Shape Prediction Model for Sendzimir Rolling Mills

It is difficult to obtain the desired strip shape using Sendzimir rolling mills because small diameter work rolls can be easily deformed by the roiling force. To control the strip shape effectively, it is important to understand the relationship between the behavior of the shape actuator and the variation of the strip shape. A numerical model based on the contact element method was proposed for the prediction of strip shape. In this numerical model, the re- lationships between the actuating forces, the roll deflections, the thickness profiles of the entry and exit sides, and the strip shape were considered. The proposed numerical model for strip shape prediction was evaluated by computer simulation and experiment with respect to various AS-U roll and first intermediate roll positions.

Compensation Model for Shape Measuring of Cold Strip Rolling

Some unavoidable factors in the process of cold strip shape measurement interfere with the shape meter, so the shape measuring results cannot reflect the true shape of the strip and the measuring precision is low. The influ- ences of the measuring error of the strip edges, the transverse temperature difference of the strip, the deflection of shape detection roller, and the shape of the strip coil on the shape measuring results were analyzed in detail, and the corresponding compensation models were established. The simulation calculation and analysis were carried out on a cold strip mill, and a number of disciplinarian cognitions were obtained.

冷轧带材板形判别模型的分析与讨论

应用有限条法求解冷轧带材的板形判别模型，并提出了新的分析方法。针对典型的残余应力分布模式，讨论了残余应力分布特征和偏差大小及带材宽厚比变化对板形判别和板形状态的影响规律。

济钢1700mm热带钢轧机的板形设定控制模型

济钢1700 mm热连轧是新建投产的宽带钢生产线,其F2—F6精轧机组装备有工作辊弯辊和窜辊技术。针对这种典型机型,在大量有限元模拟计算的基础上,开发了相应的板形设定控制模型,包括工作辊综合辊形(初始辊形、磨损辊形和热辊形之和)计算模型、支承辊综合辊形计算模型、窜辊设定计算模型和弯辊力设定计算模型等。在经历了系统设计、程序编写、离线调试、在线调试后,板形设定控制模型投入稳定运行,所有考核规格的凸度控制精度超过96%。在同宽轧制长度超过70 km的轧制单位内,各机架弯辊力设定结果能够自动适应带钢厚度和钢种的变化,且凸度控制精度超过95%。

热带钢轧机板形综合控制技术开发

为了改善热带钢轧机的板形控制性能、提高产品的板形质量、降低生产消耗,针对工作辊可轴向窜动的热带钢轧机,在大量有限元模拟基础上开发了特殊的工作辊辊形技术和支持辊辊形技术及相应的板形控制模型,包括过程控制系统(L2级)的板形设定控制模型和基础自动化系统(L1级)的弯辊力前馈控制模型、凸度反馈控制模型及平坦度反馈控制模型.在经历离线模型建立、在线编程和调试等诸多复杂过程后,辊形技术及板形控制模型在工业宽带钢热轧机上进行了长期、稳定的应用.生产实践表明,采用这些板形控制技术后,凸度偏差控制在±18μm的比例超过93%,平坦度偏差控制在±25IU的比例超过94%,同时实现了自由规程轧制.

梅钢热轧板板形控制优化

介绍了梅山钢铁股份有限公司热轧板厂在对1422mm热连轧机的技术改造中,通过采用CVC辊型、弯辊和轧辊轴向横移等板形控制技术,以及板形设定模型来控制板形。通过对数学模型和工艺参数的优化,有效地提高了板形质量。

400HC轧机板形设定控制数学模型

为了提高冷轧带材的板形质量，特别是无板形闭环控制的中小型轧机所生产带材的板形质量，必须有高精度的板形设定控制数学模型。本文通过对冷轧带材的三维弹塑性变形分析和ＨＣ轧机辊系弹性变形计算，以及系统的实验研究，建立了ＨＣ轧机板形设定控制的纯理论数学模型和４００ＨＣ轧机板形设定控制的理论—实测回归模型。模型精度较高，应用于实际生产，提高了带材的板形质量，取得了明显的经济效益。

万能凸度轧机非对称板形调控特性与广义整体板形控制策略研究

随着板形质量精度要求的不断提高以及板形控制技术的显著进步,非对称板形缺陷逐渐凸显为带钢轧制质量控制的重要技术难点。根据目前新建万能凸度轧机(Universal crown mill,UCM)逐渐具备新型非对称板形控制手段——反对称弯辊的有利条件,通过ANSYS有限元仿真计算软件,建立高精度辊系—轧件一体化耦合模型,分析UCM各对称与非对称板形控制手段沿带钢全宽调控特性的差别,并以板形调控功效矢量的形式进行定量表示。在仿真基础上,提出基于板形调控功效矢量的广义整体板形控制策略,并设计完整的板形设定计算模型与闭环控制模型。通过仿真试验表明,该控制策略能够很好地通过各对称与非对称板形控制手段的有效配合实现对复杂模态板形的有效控制,具有广阔的研究与应用前景。

1700mm热带轧机板形预设定控制系统的研究

介绍了某厂1700mm热连轧板形预设定控制系统的控制策略、主要物理模型及其实际应用效果,该控制系统具有较高的精度,可用于在线实际生产。

双机架冷轧弯辊力综合设定模型的研究

针对双机架冷轧机组的生产工艺特点,以及传统弯辊控制技术的不足,综合协调控制1#机架工作辊、1#机架中间辊、2#机架工作辊和2#机架中间辊4部分弯辊力,以成品板形质量最佳为优化目标函数,同时将各个部分弯辊力的相对余量均匀作为约束条件,确定出弯辊力综合设定模型,该模型可提高弯辊对板形的控制能力,延长弯辊缸的使用寿命。

热带钢连轧机板形设定控制数学模型

将轧件三维塑性变形模型、辊系弹性变形模型和轧后带材失稳判别模型联立，组成完整的板形分析和控制数学模型，对１６６０ｍｍ七机架热带钢连轧机进行了板形设定控制的计算，板形和板凸度的实际控制效果良好。

宝钢热轧厂新CVC板型控制模型的应用

介绍了宝钢热轧厂新ＣＶＣ板型控制模型的应用及实际控制效果

铝带坯铸轧板形测控的补偿模型

根据铸轧板形缺陷的表征特点及其评价指标 ,采用铸轧板带的横向板厚分布作为板形控制信号 ,并依此建立了铸轧板形的数学描述 .基于铸轧工艺的特点 ,在铸轧板形实测信号中通常包含铸轧带材横向温差及板凸度所致的两种附加干扰 ,通过具体分析两种附加干扰对铸轧板形测控的影响 ,分别建立了附加温差板形补偿模型和附加板凸度板形补偿模型 .针对某铸轧机实轧工况 ,运用所建补偿模型求得了横向板厚的补偿值 ,并直接对板形检测信号进行修正 ,以期提高板形控制精度 ,避免板控执行机构的误操作 .实测结果表明所建补偿模型正确 ,且处理方法简单 ,可直接用于铸轧板形的控制 .图 1,表 1,参

四辊冷轧机板形前馈模型的研究

针对四辊冷连轧轧机,研究了采用工作辊弯辊力补偿的板形前馈模型。用Abaqus有限元软件模拟板形前馈模型参数,分析了轧制力波动量、轧制力对板形前馈模型的影响。对比了板形前馈模型有限元计算值和设定值,对比发现吻合较好。本文对于带材冷轧板形前馈模型参数设定具有重要意义。

热轧带钢生产线板形质量异议分析与对策

分析了涟钢CSP、2250mm生产线板形质量异议数据,通过将市场反馈数据与在线数据进行对比,找出板形质量异议存在的共性原因。根据板形质量异议的特点,通过平整工艺制度优化、辊型优化设计、板形控制模型参数调整、板形目标值修改、板形质量预判定、轧制工艺规范完善等方法,减少了板形质量异议发生的风险。通过在现场进行了一年多的质量异议分析及方案运行,热连轧机组板形质量异议半年周期内同比下降39.69%。