Development and application of cold strip rolling flatness control system in Ansteel

In this paper,the flatness control technology AnShaper^(TM) for cold-rolling mill and industry application are introduced.AnShaper^(TM) includes;partitioning piezomagnetic shape meter for flatness measurement for cold-rolling strip;flatness measured signals processing system based on digital signal processing(DSP);flatness feedback control model system based on the control efficiency of flatness control actuators and model adaptive function.The application verifies that strip flatness can meet the need of high quality product by using AnShaperTM.The average flatness quality is about 5Ⅰ-unit and the 0.18 mm ultrathin thickness strip flatness is 10Ⅰ-unit.

Tension and Thickness Control Strategy Analysis of Two Stands Reversible Cold Rolling Mill

In order to lucubrate the rolling characteristic of the two stands reversible cold rolling mill and establish the tension and thickness control strategy, the steady-state characteristic simulating program was established using the steady-state continuous rolling theory. The influences of each factor on exit thickness under different tension control methods were analyzed. The results show that, the influence of the entry stand gap on exit thickness is significant and it changes little with different tension control methods. As a result, the entry stand gap can be used as the main control method of exit thickness, whereas rolling speed of any stand and roll gap of the exit stand can be used to adjust the inter-stand tension. The results are beneficial for thickness and tension control of the two stands reversible cold rolling mill.

Actuator Efficiency Adaptive Flatness Control Model and Its Application in 1250 mm Reversible Cold Strip Mill

The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation , which is used for general flatness control.As the basis of flatness control system , the efficiencies of flatness actuators provide a quantitative description to the law of flatness control.Therefore , the determination of actuator efficiency factors is crucial in flatness control.The strategies of closed loop feedback flatness control and rolling force feed-forward control were established respectively based on actuator efficiency factors.For the purpose of obtaining accurate efficiency factors matrixes of flatness actuators , a self-learning model of actuator efficiency factors was established.The precision of actuator efficiency factors can be improved continuously by the input of correlative measured flatness data.Meanwhile , the self-learning model of actuator efficiency factors permits the application of this flatness control for all possible types of actuators and every stand type.The application results show that the self-learning model is capable of obtaining good flatness.

Research and Application of Non-symmetrical Roll Bending Control of Cold Rolling Mill

The existing research of the flatness control for strip cold rolling mainly focuses on the calculation of the optimum adjustment of individual flatness actuator in accordance with the flatness deviation, which can be used for general flatness control. However, it does not work for some special rolling processes, such as the elimination of ultra single side edge-waves and the prevention of strip break due to tilting roll control overshooting. For the purpose of solving these problems, the influences of non-symmetrical work roll bending and intermediate roll bending on flatness control were analyzed by studying efficiencies of them. Moreover, impacts of two kinds of non-symmetrical roll bending control on the pressure distribution between rolls were studied theoretically. A non-symmetrical work roll bending model was developed by theoretical analysis in accordance with practical conditions. The model was applied to the revamp of a 1250 6-H reversible universal crown mill (UCM) cold mill. Theoretical study and practical applications show that the coordination utilization of the non-symmetrical work roll bending control and tilting roll control was effective in flatness control when there appeared bad strip single side edge waves, especially when the incoming strip was with a wedge shape. In addition, the risk of strip break due to tilting control overshooting could be reduced. Furthermore, the non-symmetrical roll bending control can reduce the extent of uneven distribution of pressure between rolls caused by intermediate roll shifting in flatness control and slow down roll wear. The non-symmetrical roll bending control technology has important theoretical and practical significance to better flatness control.

Transverse thickness difference control technology for non-oriented silicon steel

Transverse thickness difference is an important quality index of non-oriented silicon steel strips. In order to fulfill users＇ accuracy requirements on the transverse thickness of silicon steel and improve the production yield, the factors influencing transverse thickness difference were analyzed. Then the work roll shape, control strategy and incoming hot-rolled strips were optimized. Since the optimization measures were implemented in the actual production, the thickness difference of non-oriented silicon steel has been reduced greatly and fulfilled the requirements placed by users. These measures have achieved remarkable effects.

Control Strategies of Asymmetric Strip Shape in Six-High Cold Rolling Mill

It is a complicated problem for cold-rolled strip to improve asymmetric strip shape in strip production. A roll system and strip coupled model of six-high cold rolling mill was established with finite element method to estimate the effect of intermediate roll shifting, tilting, symmetric and asymmetric bending technologies on strip profile. To reduce asymmetric defects of strip shape as much as possible, some control strategies were proposed, including tilting and asymmetric bending of intermediate roll and work roll. The combinations of these three control strategies can effectively eliminate asymmetric strip shape defects. Finally, the closed-loop control model of asymmetric flat- ness at the last stand was given, and the flatness control system with the function of asymmetric strip shape control was also designed for cold tandem mill.

CVC四辊冷轧机板形控制策略

研究了宽带冷轧机的板形控制策略理论问题以及ＣＶＣ四辊冷带轧机建立合理的板形控制策略的一般方法，在此基础上，以宝钢冷连轧机的第五机架为对象，建立了一套适用的板形控制策略模型。

CVC轧机冷轧宽带材板形控制特性的数值模拟

以六次偶函数拟合宽带材入出口横向厚度分布，计算了ＣＶＣ轧机冷轧宽带材前张应力横向分布，首次以张应力横向分布的形式，模拟了ＣＶＣ轧机冷轧宽带材板形控制特性。

CVC冷轧机承载辊缝凸度调节域计算模型

开发了四辊CVC冷轧机承载辊缝凸度调节域预报模型,其将承载辊缝分为空载辊缝凸度与变形辊缝凸度两部分。以某厂CVC轧机为例,计算的凸度调节域与影响函数法计算的凸度调节域相吻合,可在线对不同工况下的轧机进行板凸度的预设定。

CVC轧机板形控制系统介绍及常见缺陷分析

摘要介绍了首钢京唐公司冷轧作业部2230酸轧生产线板形控制系统的结构及工作原理，并对常见板形缺陷及原因进行了分析。

宽带钢热轧机CVC辊型优化与应用

针对涟钢2250mm常规热连轧机组F5～F7机架CVC工作辊横移量及分布不合理、轧机凸度控制能力不足的问题，通过建立CVC辊型模型对其进行了优化设计。现场实验表明，CVC辊型优化后，工作辊横移全行程利用率得到了有效提高，工作辊弯辊的板形调控功效也得到了更好发挥，满足了板形控制的需要。

四辊CVC热连轧机工作辊辊型设计

根据热连轧CVC轧机的工作原理,探讨了CVC轧机反对称曲线辊型的设计方法。板形控制研究与轧辊的曲线设计一直是带钢生产技术领域的核心问题,因此,对于板形及轧辊的研究无疑具有重大的理论价值和现实意义。

Data-based flatness prediction and optimization in tandem cold rolling

In cold rolling process,the flatness actuator efficiency is the basis of the flatness control system.The precision of flatness is determined by the setpoints of flatness actuators.In the presence of modeling uncertainties and unmodeled nonlinearities in rolling process,it is difficult to obtain efficiency factors and setpoints of flatness actuators accurately.Based on the production data,a method to obtain the flatness actuator efficiency by using partial least square(PLS)combined with orthogonal signal correction(OSC)was adopted.Compared with the experiential method and principal component analysis method,the OSC-PLS method shows superior performance in obtaining the flatness actuator efficiency factors at the last stand.Furthermore,kernel partial least square combined with artificial neural network(KPLS-ANN)was proposed to predict the flatness values and optimize the setpoints of flatness actuators.Compared with KPLS or ANN,KPLS-ANN shows the best predictive ability.The root mean square error,mean absolute error and mean absolute percentage error are 0.51 IU,0.34 IU and 0.09,respectively.After the setpoints of flatness actuators are optimized,KPLS-ANN shows better optimization ability.The result in an average flatness standard deviation is 2.22 IU,while the unoptimized value is 4.10 IU.

冷轧板形数字孪生模型与协调优化信息物理系统

板形控制过程具有非线性、遗传性、强耦合等特征,现有的数学模型不能充分描述这些关系;同时,蕴含在钢铁大数据中的价值没有得到充分挖掘,在由“数据”到“信息”的处理过程中存在断层,没有形成对板形控制的良好反馈。为提高板形控制水平,首先设计了一种融合集成经验模态分解和小波变换的轧制生产数据降噪方法,实现高噪声条件下有效信息的准确提取;以此为基础,提出使用正交信号校正改进的偏最小二乘算法,结合生产数据实时优化板形调控功效系数,准确描述了实际数据中板形变化量与执行机构调节变化量的比例关系。通过对轧制过程数据的治理与高精度板形调控功效系数的获取,建立起了与六辊轧机实体系统相互映射的虚拟镜像,实现了板形控制数字孪生模型的构建。之后,以板形解析机理模型和经验知识为先导,分别基于核偏最小二乘法和深度神经网络算法建立了板形预测模型,并在预测效果更好的基于深度神经网络算法的板形预测模型基础上,提出了启发式算法和梯度下降算法相结合的板形设定智能优化方法。最终,通过构建以数字孪生模型为核心、以多目标协调优化为特征的板形控制信息物理系统,成功实现了冷连轧多机架工艺参数的动态优化设定,板形标准差由优化前的3.42 IU降至1.91 IU。

冷轧平整机延伸率自动控制策略研究

为了解决平整机延伸率控制系统控制精度低、带钢升减速过程延伸率波动大等问题,提出了从S辊调速系统,轧制力压下系统和张力调节系统等方面的改进控制策略,并引入了模糊自适应PID算法模拟仿真试验分析,实现了对不同厚度带钢参数自适应调节。通过某钢铁冷轧厂150 cm平整机延伸率控制系统的实际应用,使用改进的控制策略后,带钢低速延伸率偏差不高于0.1%,带钢高速延伸率偏差低于0.05%,大大提高了平整机延伸率的控制精度,满足了用户对工艺的需求。

冷轧机主传动控制系统的优化分析

为有效解决主传动控制系统在实际生产中存在的一系列问题,有效提升冷轧机产品质量和生产效率,在对冷轧机设备及工艺进行简单概述的基础上,应用交直交变频调速系统为核心的主传动控制系统,并完成核心设备的选型,通过仿真对比分析确定采用了基于遗传算法的PID控制策略,从而实现对冷轧机主传动系统的高效控制。

冷轧板形测量值计算模型的研究与应用

为了得到准确的板形测量值,通过分析板形辊的结构与板形测量原理,制定板形测量信号的标定及滤波处理方法。为了补偿带钢横向厚差对板形测量的影响,建立轧后带钢横向厚度分布模型,把各个测量段处的带钢厚度引入张应力分布计算模型中,提高了带钢张应力分布计算的精度。根据带钢与板形辊的接触状态设定带钢边部板形测量值的补偿计算模型,用于修正未被带钢边部全部覆盖的传感器所测径向力。针对轧制过程中板形辊上某些传感器会出现故障的情况,制定故障测量段的插值计算方法。给出由各测量段板形测量值向若干个特征点处板形值的转换模型,简化板形控制系统中的数据处理过程。板形测量值计算模型已用于1450冷连轧机的板形控制系统改造中,经现场应用表明,模型具有较高的精度,为冷轧板带生产实现精确的板形控制提供条件。

冷轧宽带钢板形检测与自动控制

综述了冷轧宽带钢板形自动检测与自动控制模型，为板形自动控制技术的发展创新提供了基础。

SmartCrown四辊冷连轧机工作辊辊形

针对宽带钢冷连轧机首次应用的SmartCrown板形控制新技术,通过对SmartCrown辊形的函数结构和特征参数进行研究,推导出了SmartCrown辊形设计式,分析了辊形特征参数对辊缝形状的影响.该研究可用于SmartCrown工作辊的磨削及板形控制.

1220冷连轧机板形控制性能综合改善

针对1220冷连轧机生产中存在的板形问题,将理论分析、计算机仿真与现场实验相结合,全面研究其原料特点和板形控制的装备、工艺、数模技术现状后,提出合适的板形控制策略,并重新设计辊系初始辊形、建立板形控制目标曲线、调整弯辊力模型,提高了连轧机组板形控制性能和板形控制系统精度,使产品板形质量、轧制稳定性和轧辊表面磨损状态明显改善。