轧辊弹性压扁对中厚板轧制压力预报精度影响的研究

建立中厚板轧制压力计算模型,分别采用简单轧制情况和考虑轧辊弹性压扁情况下轧件与轧辊接触面积计算模型来预报轧制压力,分析轧辊弹性压扁对中厚板轧制力预报精度的影响。结果表明,在中厚板轧制过程中考虑轧辊弹性压扁的情况下,当预报轧制压力小于实测值时,轧制压力的预报精度提高;当预报轧制压力大于实测值时,轧制压力的预报精度降低。     

中厚板轧机弹跳模型的数值分析和应用

针对普通4辊中厚板轧机将辊系弹性变形分解成3个部分：支撑辊挠曲变形、辊间压扁和工作辊压扁，并利用轧辊弹性变形的数值解法一影响函数法对这3部分变形进行了分析，得出了轧辊半径、轧辊凸度、轧件宽度和轧制力等因素对辊系弹跳的影响规律，并提炼出相应的高精度回归模型。同时对传统轧机弹跳模型进行改造，提出更加完备的轧机弹跳模型。利用该模型可以很方便地计算轧辊辊径、凸度和轧件宽度对轧机弹跳的影响。通过与X射线测厚仪测试结果相比较可知，模型预测误差小于0．12mm，有利于负公差轧制。     

超高强钢冷轧过程轧制力计算的改进模型

 为了解决采用圆弧模型计算超高强钢冷轧过程轧制变形区轧辊压扁曲线误差较大的问题,充分考虑到超高强钢的轧制特点,通过分析不同压扁半径下轧辊压扁曲线的变化规律,构造出新型轧辊压扁曲线函数模型,给出了该函数中轧制变形区接触弧长特性参数与轧辊压扁曲线特性参数的求解方法。基于此,根据弹塑性理论中的变形与应力关系,推导了入口弹性变形区、塑性压下变形区以及出口弹性变形区单位轧制压力分布计算过程,建立了超高强钢冷轧过程总轧制力计算模型。并将其推广应用到某钢厂2030冷连轧机组,验证了该模型的计算准确度。结果表明,超高强钢冷轧过程轧辊压扁曲线用二次函数表示,更能准确反映轧辊压扁状态,其计算结果与实际值具有较高的吻合度。同时,为冷连轧机组生产超高强钢产品极限轧制能力的评估与轧制规程的制定提供了理论依据。     

轧辊弹性压扁下冷轧轧制力数学模型的研究

在冷轧轧制中,轧辊会发生严重的弹性压扁,对轧制力计算产生影响。考虑轧辊弹性压扁,建立平均单位轧制力数学模型,有重要意义。以卡尔曼单位压力平衡微分方程与采利柯夫解为基础,建立平均单位轧制力数学模型。     

考虑轧辊弹性压扁的铝带冷轧轧制力有限元模拟研究

在冷轧轧制中轧辊会产生弹性压扁,对轧制力影响较大。本文以ANSYS／LS—DYNA为分析软件,将轧辊辊身设置为弹性体,模拟分析了刚性轧辊轧制力、弹性轧辊轧制力、不带张力、带张力等情况下的轧制。从分析中,可以看出轧制力的影响规律。可以指导生产,降低试验成本,具有一定理论意义和实用经济价值。     

考虑轧件弹性变形的Hill轧制力显式公式

带钢的轧制力计算和轧辊的压扁计算互为条件 ,针对考虑轧件弹性变形的Hill轧制力公式和Hitchcock轧辊压扁公式 ,推导了它们的显式计算公式 ,从而避免了传统的迭代计算。     

考虑轧辊弹性压扁的铝带冷轧轧制力有限元模拟研究

在冷轧轧制中轧辊会产生弹性压扁,对轧制力影响较大.文章以ANSYS/LS-DYNA为分析软件,将轧辊辊身设置为弹性体,模拟分析了刚性轧辊轧制力、弹性轧辊轧制力,不带张力、带张力等情况下的轧制.从分析中,可以看出轧制力的影响规律.可以指导生产,降低试验成本,具有一定理论意义和实用经济价值.     

轧辊弹性变形和板形理论的研究

本文对轧辊弹性变形理论的几个重要问题进行了研究。在弹性力学结论的基础上,导出了辊间压扁影响函数,合理地处理了辊间压扁问题,并进而给出了计算轧辊弹性变形的矩阵计算方法。利用矩阵方法进行了双阶梯支撑辊的理论分析,并进行了实验研充。结果证明,利用双阶梯支撑辊可以排除轧制压力波动对板形的影响,可以增强弯辊效果,是一种简便有效,符合我国国情的方法。     

考虑轧件弹性变形的ill轧制力显式公式

带钢的轧制力计算和轧辊的压扁计算互为条件，针对考虑轧件弹性变形的Ｈｉｌｌ轧制力公式和Ｈｉｃｈｃｏｃｋ轧辊压扁公式，推导了它们的显工计算公式，从而避免了传统的迭代计算。     

板材轧制中的拉拔效应及热塑有限元计算

采用热塑性有限元进行计算,热塑性有限元是一种三维的弹塑性有限元,它用板材轧制时存在的“拉拔效应”对变形区进行修正,求出正确的变形区。并计算出轧辊的弹性压扁、精确计算轧制力、轧制力矩、板凸度、板形和辊凸度,获得提高板形质量、减少板厚差、增加轧辊调整余地和使辊子耐磨的效果。     

极薄带轧制变形区轧辊压扁试验与有限元模拟

 极薄带在轧制及平整过程中,工作辊的弹性压扁对轧制压力的分布有很大影响,传统的轧制力模型已经不再适用。为了在极薄带板形板厚控制过程中得到准确的轧制力,Fleck提出了新的轧辊压扁模型。针对Fleck模型进行试验研究,同时进行有限元模拟分析。试验过程中使用合金工具钢轧辊,轧制不同厚度的轧件,通过显微镜测量变形区各部位的厚度,得到变形区轧辊的近似轮廓形状。试验与有限元模拟结果表明,随着轧件厚度的减小,变形区出现了明显的中性区,但是很难出现Fleck模型中提到的弹性卸载区,因此计算极薄带轧制力时可以忽略中性区内的弹性卸载区以简化轧制力模型。     

Precise calculation of average strain and average strain rate considering roll elastic flattening

Considering roll elastic flattening,newequations were proposed to calculate the average strain ε and·average strain rate ε in the hot strip rolling process. By comparing the proposed equations with currently used equations,it was observed that the strain rate of thick strip and strain are not sensitive to roll elastic flattening.However,for thin strip,a noticeable calculated difference in the strain rate occurred when roll elastic flattening was considered.     

变接触长度支承辊间等接触压力时轧辊变形规律

以某中板厂生产条件和数据为基础,讨论了变接触长度支承辊辊间接触压力相等时的轧辊变形情况.在不同轧制压力前提下,首先计算出轧辊辊身中点处及轧辊与轧件边部相对应点处的变形,然后再绘制出变形沿辊身的分布规律,发现压扁变形比弯曲变形大,同时当轧制压力增大时,轧辊变形随辊身长的变化率亦会增大.     

Influence of Roll Elastic Deformation on Gaugemeter Equation for Plate Rolling

The error of gaugemeter equation decreases the gap setting precision. The precision of gaugemeter equation is strongly influenced by plate width, work roll radius, backup roll radius, work roll crown, backup roll crown and rolling force. And these influences are hard to measure. All these factors are converted to roll deflection deformation and roll flattening deformation for calculation. In order to calculate the deformation, the theory of influence function method was adopted. By using simulation program, the influence of these factors on deformation was obtained. Then a simple model can be built. With this model, it is convenient to analyze the influence of different factors on gaugemeter equation.     

Influence of roll geometry and strip width on flattening in flat rolling

The size of local roll flattening and its distribution along the direction of the roll axis in flat rolling were calculated by means of 3-dimensional finite element method. For analysis of elastic flattening deformation of the roll stack the well-known classical and analytical solutions are usually employed which were derived from elastic half space theory or two dimensional contact theory. By comparison of results from both the different methods the validity of the classical formulae was examined. Some of the formulae are more appropriate for calculating local flattening along the work roll/strip interface, however, they may result in a great deviation in calculating the flattening along the work roll/ back-up roll interface, especially for the back-up roll. Using the Fe model the influence of roll geometry and strip width under a specific rolling force on the flattening was taken into account, which is difficult to be treated with classical models.     

Experimental and theoretical analysis of roll flattening in the deformation zone for ultra-thin strip rolling

For ultra-thin strip rolling, the conventional rolling force models are no longer applicable. To obtain accurate rolling force in the shape and gauge control process, Fleck proposed a new roll flattening model. In this study, experimental analysis, finite element simulation, and theoretical analysis were conducted to evaluate the Fleck model. The experiments and simulations show a clear neutral zone in the deformation zone with decreasing strip thickness. The finite element simulation results show that the proportion of the elastic unloading zone is small, when an elastic unloading phenomenon appears in the neutral zone. Thus, to simplify the rolling force model, the effect of an elastic zone could be ignored. Based on this finding, we develop a rolling force model with quick calculation speed, high precision, and convenient online application. Finally, the accuracy of the simplified model is verified by the measured rolling force.