板宽对轧辊受力分布的影响规律

轧辊受力分布的形态直接影响轧辊的弹性变形和轧件的出口板凸度.基于影响函数法,对轧机辊系受力和轧辊弹性变形进行计算分析,研究了轧制过程中板宽对轧制压力、辊间压力横向分布的影响.分析表明,边部轧制压力先随着板宽的增大而增大,达到某极值点后又逐渐减小;而随着板宽的增大辊间平均压力增大,压力分布变得不均并向轧辊端部集中;这些规律为不同板宽轧件的轧制规程安排、轧辊磨损的计算分析以及轧件出口板凸度的计算模型与控制提供了基础.     

四辊PC轧机辊间接触应力及支承辊疲劳损伤分布研究

四辊轧机辊系中辊间循环接触应力引起的辊身接触疲劳损伤,会影响辊身的磨损、轧辊的后续磨削及使用寿命;因此分析不同轧制工艺参数情况下辊间接触应力的分布对分析辊身损伤以及现场轧辊维护具有重要的意义,以某厂1880轧线采用的四辊PC轧机为研究对象,采用有限元法分析了不同工艺参数对辊间接触应力分布及分布均匀度的影响规律;基于损伤累积理论建立了轧辊辊身截面损伤分布计算模型并计算了辊身轴向截面内的接触疲劳损伤分布,与现场辊身疲劳硬化测试结果对比表明理论分析结果具有一定的合理性。     

UCM冷连轧机辊型曲线优化设计

以900mm四机架六辊UCM冷连轧机组为研究对象,建立了轧辊辊间接触压力和板形计算模型,以均匀辊间接触压力分布和板形良好为目标,对机组轧辊辊型曲线进行了优化设计.理论计算表明,优化后的辊型曲线均匀了辊间接触压力分布,降低了辊端接触压力峰值,同时能够提高弯辊力对板形的控制效果.工业生产试验后正式推广使用,支承辊和中间辊掉肩和掉肉现象得到了全面遏制,板形质量得到良好控制.     

六辊CVC宽带轧机轧辊接触压力横向分布特性的计算机仿真

用条元法分析带材的三维塑性变形,用影响系数法分析辊系的弹性变形,将二者联立,对1850mm六辊CVC轧机冷轧带材轧辊接触压力的横向分布进行了计算机仿真。结果表明,CVC中间辊横向移动、工作辊弯和中间辊弯辊等手段,对轧制压力的横向分布影响很大,对辊间压力的横向分布也有明显影响。在各种情况下,辊间压力都呈S形分布。     

20辊森吉米尔轧机辊系静压力学计算与分析

在对轧机辊系结构稳定性和板形控制的研究中,辊间接触参数的分布和相互关系是其研究的基础和关键。以某硅钢厂ZR22BS-42型轧机辊系为研究对象,建立20辊森吉米尔轧机辊系力学模型,并对各轧辊进行受力分析。采用MFC(Microsoft Foundation Classes)搭建程序界面,首先计算了辊系静压状态下辊间接触力、接触力方向角以及各辊合力的大小,再对其分布关系进行了具体分析。利用有限元软件进行辊间接触应力仿真计算,通过对模型的有效简化,设置12个接触对,根据静压过程的受力特性确定辊系的载荷约束。最后,对比辊间接触的应力云图,定量确定了各辊间的接触应力大小,并分析了应力变化的趋势及相互关系。实验结果有利于指导轧机的压下和辊型调整。     

四辊轧机接触压力及剥落问题的研究

采用有限元法研究了在任意工况下四辊轧机工作辊与支承辊间接触压力沿横向分布的计算原理及技术要点,并对影响冷轧工作辊寿命的辊面剥落问题进行分析,提出了防止轧辊早期剥落破坏以延长其使用寿命的方法。     

轧机工作辊有限元分析

四辊轧机在工作过程中,工作辊既承受工件的变形抗力,又承受轧机轧制力和弯辊力的共同作用,造成辊身应力状态复杂。为保证轧辊的合理与优化设计,采用有限元方法针对轧辊工作过程进行分析,提出了一种有限元模型建模方法,准确计算出工作辊在工作过程中的变形和应力分布。计算结果为轧辊的结构改进与优化设计提供依据,以提高轧机的设计水平。     

考虑轧辊非均质特性的辊间接触应力分布规律研究

考虑轧辊表面淬硬层与其心部金属材料组织性能的差别，采用非线性有限元方法对四辊轧机的工作辊与支撑辊间接触应力及辊内剪应力分布进行模拟，并将模拟结果与传统强度校核方法进行了对比分析，研究了轧辊淬硬层厚度对辊间接触应力的影响规律。该项研究对于深入分析轧辊的失效行为具有重要的意义，为制定准确、可靠的轧辊强度校核判据提供了新的思路。     

基于影响函数法的轧制压力横向分布规律分析

轧制压力横向分布直接影响轧辊的弹性变形和轧件的出口厚度分布。文中基于影响函数矩阵法,对轧机辊系受力和弹性变形进行计算分析,研究轧制过程中弯辊力和压下率对轧制力横向分布的影响,揭示轧制压力横向分布系数与弯辊力呈近似线性增长、与压下率呈近似线性减小的规律。分析表明,通过调节弯辊力或在轧制规程中改变压下率设定,可改变轧制压力的分布。为轧制压力横向分布函数的在线快速计算和板凸度控制模型的建立提供基础。     

四辊行星轧机(KRM)轧制空间关键几何参数的研究

四辊行星轧机(KRM)是继三辊行星轧机(PSW)之后出现的新型行星斜轧机,这是轧管技术的一个新进展,有着很大的发展潜力。文中在三辊行星轧机研究的基础上运用解析法,首次推导出了与四辊行星轧机轧制空间相关的关键几何参数,并给出了四辊行星轧机孔型曲面设计和轧辊间干涉检验的方法,为进一步研究四辊行星轧机轧辊设计理论及工程应用等方面提供了依据。     

Coupled dynamic modeling of rolls model and metal model for four high mill based on strip crown control

The crown is a key quality index of strip and plate,the rolling mill system is a complex nonlinear system,the strip qualities are directly affected by the dynamic characteristics of the rolling mil.At present,the studies about the dynamic modeling of the rolling mill system mainly focus on the dynamic simulation for the strip thickness control system,the dynamic characteristics of the strip along the width direction and that of the rolls along axial direction are not considered.In order to study the dynamic changes of strip crown in the rolling process,the dynamic simulation model based on strip crown control is established.The work roll and backup roll are considered as elastic continuous bodies and the work roll and backup roll are joined by a Winkler elastic layer.The rolls are considered as double freely supported beams.The change rate of roll gap is taken into consideration in the metal deformation,based on the principle of dynamic conservation of material flow,the two dimensional dynamic model of metal is established.The model of metal deformation provides exciting force for the rolls dynamic model,and the rolls dynamic model and metal deformation model couple together.Then,based on the two models,the dynamic model of rolling mill system based on strip crown control is established.The Newmark-β method is used to solve the problem,and the dynamic changes of these parameters are obtained as follows:(1) The bending of work roll and backup roll changes with time;(2) The strip crown changes with time;(3) The distribution of rolling force changes with time.Take some cold tandem rolling mill as subject investigated,simulation results and the comparisons with experimental results show that the dynamic model built is rational and correct.The proposed research provides effective theory for optimization of device and technological parameters and development of new technology,plays an important role to improve the strip control precision and strip shape quality.     

四辊CVC热带钢轧机板形控制特性的仿真

用流面条元法分析带材的三维塑性变形．用影响系数法分析辊系的弹性变形，将两者耦合，建立了四辊轧机板形和板凸度的分析计算模型。对四辊CVC热带钢轧机板形控制特性的仿真表明，随着CVC工作辊横移距离的增加，前张应力沿横向的差距增大；随着工作辊弯辊力的增加，前张应力沿横向的差距增大，且变化主要集中在板宽的边部；随着板宽的增加，前张应力沿横向的差距先减小后增大。     

Shape control of alloy steel rolled by sendzimir mill

In order to improve quarter waves occurred in the wide and thin gauged alloy steel rolled by 20-high sendzimir mill, a computer simulation based on the divided element method and an actual cold rolling experiment were carried out. Quarter waves were simulated by elastic deformation analysis of rolls considering bending deformation of back up rolls and the effect of control actuators on controllability of quarter waves were analyzed. Computer simulation showed that control actuators such as shifting of the 1st intermediate roll and crown adjustment of As-U-Roll in back up rolls were not effective to control quarter waves and that changing taper mode (both length and magnitude) at the barrel-end taper radius of the 1st intermediate roll was rather very effective. From an actual rolling experiment it was verified that quarter waves could be reduced remarkerably by changing taper mode of the 1st intermediate roll.     

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.     

弯辊系统在四辊轧机辊缝控制中的应用研究

以四辊轧机的弯辊系统为研究对象,利用有限元分析软件ANSYS研究弯辊力和辊间接触应力引起工作辊形状的变化,计算工作辊弯曲的最大变形量,并用最小二乘法对辊缝曲线进行拟合,为进一步计算有载辊缝形状提供可靠的理论依据。     

Roll shape design for foil rolling of a four-high mill

In this paper, a mathematical model for a four-high mill is proposed to analyze the elastic deformation of the backup and work rolls, including their respective axial deflection and surface flatness. The contact pressure between the backup and work rolls and that between the work roll and foil are functions of the roll’s position in the axial direction. In this analytical model, the rolls and foil are divided into many small regions and finite difference or matrix methods are used to derive the deflections of the work and backup rolls as a function of the force density in the foil width direction. A camber shape at the surfaces of the backup and work rolls is designed to counteract the rolls’ elastic deformation and to make the rolled foil as flat as possible. The effects of the selected roll materials upon the rolled thickness distribution are also discussed. A thickness variation within 1 μm can be obtained for a foil of 50-μm thick and 40-mm wide under reduction of 32 % using a WC work roll with a camber radius of 150 m.     

Study on the improved accuracy of strip profile using numerical formula model in continuous cold rolling with 6-high mill

The quality requirements for thickness accuracy in cold rolling continue to become more stringent. In cold rolling mill, it is very important that the rolling force calculation considers rolling conditions. The rolled strip thickness was predicted using calculated rolling force. However, the prediction of strip thickness in cold rolling is very difficult; in particular, for 6-high mill with shifted intermediate roll (IMR), the accuracy of thickness is not good. In this study, to improve the accuracy of rolled strip thickness, the roll gap flattening can be given based on Hertz contact theory, with contact between rolls and the smooth cylindrical rolls for the rolling elastic deformation. Also, the distribution of the roll gap flattening may be calculated using the contact force of unit transverse length. The strip profile at the continuous cold rolling is calculated by using the numerical analysis model considering the initial strip profile before cold rolling. Hence, we propose that the numerical model can predict the rolled strip profile more quickly and accurately and be applicable to the field. The results of the proposed numerical model were verified by FE-simulation and cold rolling experiments of 6-high mill with five stands.     

一种多功能的轧辊拆装机

介绍大型型钢生产线中末架精轧机轧辊更换拆装机的工作原理、设备组成及结构特点,对主要液压缸的力能参数进行实例计算。