中厚板轧制过程中的辊缝设定模型及其应用

结合首钢3500mm轧机改造项目，根据中厚板轧制工艺的特点，详细分析了中厚板轧制过程中辊缝设定模型的各种影响因素，并给出了相应的高精度补偿模型，如轧机的自然刚度、油膜厚度变化等。分析了轧件入口厚度偏差对辊缝设定的影响及其在线消除。现场的在线应用结果表明：运用给出的辊缝设定模型，可以大幅提高中厚板轧机的辊缝设定精度，为厚度精度的提高和AGC控制打下了良好的基础。     

AGC技术在中厚板厚度控制中的应用研究

中厚板轧机中AGC自动辊缝控制系统一般由液压辊缝控制HGC和电动辊缝控制EGC组成。采用AGC技术可以快速地在钢板厚度控制时作出响应,并及时进行控制调整,保证轧制过程中钢板的厚度控制精度。中厚板行业对标数据表明,通过对中厚板AGC自动控制系统的优化,速快完成轧机轧制过程的厚度补偿。优化自动调整控制技术,可实现轧线产能与质量等方面关键指标的提升,在各大钢厂都存在良好的应用实例。因此,在本文的研究中,将就AGC技术在中厚板厚度控制中的应用研究展开讨论。     

中厚板轧制过程消除侧弯的两侧辊缝在线调整模型

分析了中厚板轧制过程中两侧辊缝差、轧件入口横向楔形、轧件两侧温度差和轧机两侧刚度差对中厚板两侧厚度偏差的影响。根据实时检测的轧制力、辊缝等数据,利用轧机刚度和轧件塑性系数推导了消除侧弯的两侧辊缝在线自动调整模型。该模型在国内某3 500 mm轧机上进行在线应用,40 mm以下成品钢板两侧厚度偏差控制在0.12 mm以内,消除薄宽规格钢板的刮框事故,轧后钢板的侧弯得到有效控制。     

中厚板轧机两侧刚度差异对辊缝设定的影响

中厚板轧机两侧刚度的差异会导致轧制过程中轧辊发生倾斜，给辊缝的设定带来困难。为此，作者首先将S1ms轧制力公式简化成道次压下量的简单函数，然后利用该函数分析了中厚板轧机驱动侧和操作侧的刚度差异引起的轧辊倾斜对轧制力分布的影响。发现：如果轧机两侧刚度差异不大，则轧辊倾斜前后的轧制力分布曲线的积分值相等，而且轧制中心线的辊缝位置基本没有变化。根据该结论给出了实测刚度曲线的拟合方法，利用该拟合曲线进行辊缝设定可以避免刚度差异带来的影响。另外，还可将该拟合曲线作为虚拟测厚仪来计算轧件的道次出口厚度。     

中厚板四辊可逆式轧机原始辊型的理论计算

分析了中厚板轧制过程中影响实际工作辊缝的主要因素,结合新钢中板厂的生产条件和设备特点介绍了中厚板四辊可逆式轧机原始辊型的理论计算方法.     

首钢3500mm中厚板轧机AGC基础自动化系统

介绍了首钢3500mm中厚板轧机工艺参数和轧机检测仪表、以西门子simadyn D系统为核心的AGC基础自动化控制系统、过程计算机系统和网络通信系统，说明了轧机基础自动化系统的液压位置自动控制（HAPC）和轧制力自动控制（批）原理，阐述了辊缝自动控制原理和电动-液压联合快速摆辊缝原理，最后介绍了厚度自动控制（AGC）的控制方式、投入条件以及AGC系统的运行情况。     

中厚板轧机电动及液压组合压下厚度控制系统

文章针对中厚板轧机电动及液压组合压下系统,简述了轧制厚度控制技术概况;分析了液压HAGC系统;描述了组合厚度控制实现的关键技术;提出了辊缝测量常见问题及解决思路;以产品质量检测数据为依据,得出了组合厚度控制系统能有效保障中厚板产品质量的结论。     

中厚板厚度的在线软测量方法

根据中厚板的轧制特点,建立了比较完善的轧件出口厚度的软测量方法,它考虑了辊系弹性变形的影响,并引入辊缝零点漂移自学习算法,修正了轧辊磨损、热膨胀和机械间隙变化带来的影响,使轧件出口厚度的软测量模型更加完善.同时分析了实时轧制力和辊缝数据的处理方法对厚度计算的影响.在中厚板厂的应用结果表明,这种软测量方法精度较高,适合在实时中厚板轧制过程中应用.     

中厚板轧机液压AGC的工作原理

本文用以测压仪或压力传感器检测到的轧制力信号和液压缸位置传感器所监测到的液压缸位置信号作为主反馈量；以轧机出口侧的测厚仪所检测到的钢板厚度偏差作为监控反馈量，对轧机辊缝进行修正的控制方式，对中厚板轧机液压AGC的工作原理进行探讨。     

新型4700中厚板轧机

日本钢管公司福山厂于1985年投产一套新型4700中厚板轧机,用于轧制碳素钢和低合金钢板,轧制速度达6.43m/s。为改善钢板厚度不均,近年来普遍采用六辊轧机。而日本钢管公司福山厂新建的4700中厚板轧机却采用了改进型的HCW四辊轧机。     

厚度控制技术在中厚板轧制生产中的应用

本文探讨了影响中厚板厚度波动的因素，结合安钢中板厂2800mm轧机按合同轧制一批交货重量不大于理论重量船板的生产实践，总结了实际生产中实现高精度厚度控制的有效方法。     

电动压下多轧程优化规程的实现

论述了多轧程电压下生产过程中,采用综合等储备原理计算机优化规程,进行板宽和析厚控制的可行性及其效果,通过安钢２８００ｍｍ轧机上的工程实践,证明该方法是行之有效的。     

Algorithm research of the SQP method used in roll schedule calculation for Baosteel’s 5m heavy plate

Loading distribution for heavy plate mill is to find optimal control solutions under the granted performance indicators and constraints including mill capacity and hypothesis of rolling models.The solutions are quite different for different performance indicators.In the article,the performance indicators and sequential quadratic programming(SQP for short below) methods employed in 5 000 mm heavy plate mill of BaoSteel are penetratingly analyzed.Generally,the SQP method is an effective and fast way to solve the nonlinear programming problems with small or medium scale constraints.Early in 1976,Han put forward the SQP method for the first time and Powell made it perfect and accomplished the algorithm in 1977.In fact, SQP method was to turn a nonlinear programming problem to a series of sub set of quadratic programming problems.In the algorithm,each iteration step is to solve one quadratic programming problem.The optimal solutions will be gradually approached after quadratic programming problems were totally solved.When solving the quadratic programming problem,the active set strategy were employed which turned the constrained quadratic programming problem to unconstrained quadratic programming problem.The active set strategy made the whole quadratic programming problem be solved by a least square problem.And finally, the matrix of the least square problem would be decomposed by Q matrix and R matrix.After Q matrix and R matrix were obtained,the optimal solutions would be finally found.For loading distribution,the performance indicators were composed by plate shape and draft of each pass.Plate shape is represented by rolling force gradually reduced pass by pass with a tunable factor.The mill capacity is another performance indicator represented by draft of each pass.For heavy plate mill,the mill capacity here is the motor moment. For heavy draft,the motor would be overloaded especially for the first several passes;for small draft,the motor would be loaded slightly.All these would not be permitted to happen when calculating the loading distribution.The mill capacity indicator made the loading of mill just be in the middle,not too much and not too low.In the article,these two performance indicators were analyzed in detail.Examples of loading distribution results with different performance indicators were given by the SQP method.When making changes to the performance indicators,there would be different solutions to the loading distribution.For the optimal solutions to the mill,there was supposed to make changes to the factors of the performance indicators or upgrade the accuracy of the mathematical models of the rolling process.     

Independent integration practice on revamping 4200/3500 mm medium and heavy plate rolling mill of Bayi Steel in terms of process and make-up equipment

This study systematically reviews and summarizes relocation and revamping project of medium and heavy plate rolling mill in Bayi Steel.After detailed analysis was made on the main deficiency and problems of the original production line of Pudong Steel,systematical integration and improvement for the process and equipment were carried out accordingly.Through innovative practice of integration,Baosteel Engineering has greatly improved the technical process and equipment make-up,as well as the grades and quality of the products.The original man-operating line is redesigned into an automatic system controlled by Level 2 computer,reaching the advanced technical level of home-made medium and heavy plate production line in recent years.The project is constructed in two phases;The original product mix of Pudong Steel is maintained as much as possible in Phase I.After 3 500 mm single stand finishing mill is put into operation, capacity of hot- rolling medium and heavy plate reaches 650 000 t/a,with the maximum thickness at 40 mm.Equipment or facilities are reserved for production of pipeline steel and other grades.Pipeline steel, vessel plate,wind power plate and other TMCP and heat treatment products are projected in PhaseⅡ.After 4 200 mm roughing mill and its matched facilities are put into operation,capacity of hot-rolling medium and heavy plate will reach 120 000 t/a,with the maximum thickness at 80 mm.Through the optimization of process equipment and its function,the relocated medium and heavy plate mill production line has reached advanced level among similar domestic mills.The prominent achievements of the project are the revamping of thickness control system of the finishing mill and the newly installed shape control system.Automation control of the whole line is realized.     

3500mm宽厚板轧机的刚度测定与实际应用

宽厚板轧制时,各道次轧制力工作点的变化很大,从15 000~65 000 kN不等,在各个轧制力工作点轧机刚度各不相同。为了准确计算不同轧制力工作点的辊缝弹跳量,对应的轧机刚度必须精确测量。本文通过压靠法测定了不同压力点的轧机刚度,采取分段线性回归的方法,得出了不同轧制力区间的轧机刚度值,使辊缝弹跳计算的精度显著提高。     

邯钢2800mm中厚板轧机优化规程研究

优化轧制规程计算及实现的基本数学模型，由优选轧制压力公式，变形抗力，温降模型参数和精确弹跳方程构成。通过计算机模拟实验比较主要压力公式的Ｑｐ值，优选出该轧机的实用压力公式，变形抗力和温降模型参数非线性估计方法，提高了压力预报精度；反映板宽因素的非线性弹跳方程，是提高辊缝设定精度的关键。通过实测轧机横向刚度的轧制方案，优化轧制规程和不同终轧道次轧制压力规程的设定计算，并在轧机上实验，证明所研制的方法     

中厚板轧制厚控综合指标的实现

论述了中厚板轧机的一种低成本厚控综合技术。该项技术以综合等储备优化规程理论、轧机非线性弹跳方程在线动态实用技术和动态设定型AGC三项工艺理论为基础,利用现代微机控制技术,实现了轧制规程的实时最佳设定和AGC方法在技术和控制目标上的互补,通过动态设定型AGC技术,最终以简单的APC方法有效地实现了AGC动能,确保了钢板目标厚度命中率、异板差和同板差这三个互相制约的厚控指标的综合控制,在老式中板轧机上,其厚控指标达到了先进水平。     

末道次轧制力锁定法在中厚板规程计算中的应用

  在中厚板轧机无液压弯辊条件下,为防止传统轧制规程计算方法造成的板形问题,提出了一种末道次轧制力锁定的轧制规程计算方法。该方法将操作工提前给定的末道次轧制力作为轧制规程计算的约束条件之一,通过控制道次规程末道次的轧制力达到控制板形的目的。实际应用结果表明,该方法使操作工能够根据经验对板形进行有效控制,明显减少中浪、边浪等板形问题,具有良好的使用价值。     

常规中厚板轧机与炉卷轧机的对比浅析

本文叙述了炉卷中厚饭轧机技术的发展．介绍了常规中厚板轧机和炉卷轧机各自的优缺点，并对这两种轧机的工艺特点进行了比较分析。