共查询到20条相似文献,搜索用时 31 毫秒
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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。 相似文献
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XIAO Hong XIE Hongbiao ZHAO Tieyong School of Mechanical Engineering Yanshan University Qinhuangdao Hebei China 《Baosteel Technical Research》2010,(Z1)
Using three-dimensional rigid-plastic finite element method base on Lagrange multiplier to analyze the deformation of strip,influence function method to calculate the elastic deflection of rolls and three-dimensionalelastic FEM to analyze the flattening deformation between work roll and strip,a coupled model was established with a iteration way.The effect of various kinds flatness control method such as bending force,rolls shift and cross angle and also various kind of influence factors such as friction ... 相似文献
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热带钢连轧机工作辊下机后尚未完全冷却即进行磨削,残存的不均匀热变形导致磨削的工作辊辊形在空冷一段时间上机时很难达到工艺设定值.针对热辊形不易测量的特点,制定合理的物理测量方式,准确地测量了工作辊下机后的温度分布和热辊形.考虑复杂的工作辊换热边界条件,采用有限差分法对工作辊空冷时的温度场和热变形进行了数值模拟,计算结果与测试结果吻合良好.对工作辊下机后不同时刻的热变形进行仿真,通过将目标上机辊形和磨削时热辊形叠加来设定磨削辊形,为实现合理的辊形磨削提供了依据和计算方法. 相似文献
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六辊冷连轧机中间辊横移过程辊间接触压力分析 总被引:2,自引:0,他引:2
为了使轧机板形控制性能适应带钢规格材质变化,用于连续轧制高档冷轧薄带钢的六辊冷连轧机大都采取中间辊可横移技术。但是,中间辊横移必定使辊间接触压力分布更不均匀,导致出现接触压力尖峰。在中间辊横移过程中,辊间接触压力和横移阻力都会随横移速度的变化而发生改变,并可能导致辊间接触压力在轧辊端部形成更大的压力尖峰,从而造成轧辊磨损不均匀并缩短轧辊的使用周期。通过建立有限元仿真模型,以仿真模拟获得中间辊横移过程中辊间接触压力的变化规律后,优化设计轧辊辊形,并且提出使用非对称弯辊力的方法,实现了辊间接触压力的分布均匀化,降低了辊间接触压力尖峰值,并延长了轧辊的使用寿命。 相似文献
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L. Khalili S. Serajzadeh B. Koohbor 《Metallurgical and Materials Transactions B》2012,43(6):1638-1648
A mathematical model was developed to assess thermomechanical behavior of work rolls during warm rolling processes. A combined finite element analysis-slab method was first developed to determine thermal and mechanical responses of the strip being rolled under steady-state conditions, and then, the calculated roll pressure and temperature field were utilized as the governing boundary conditions for the thermomechanical problem of the work roll. Finally, the thermomechanical stresses within the work rolls were predicted by a thermoelastic finite element approach. The results of the model indicate that, in warm strip rolling, thermal and mechanical stresses developed in the work rolls are comparable, and thus, both thermal and mechanical aspects of the problem should be considered in such a problem. Besides, the model was shown to be capable of determining the effects of various rolling parameters on the thermomechanical behavior of the work rolls during warm rolling process. 相似文献
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《钢铁冶炼》2013,40(3):163-170
AbstractIn order to improve the flatness of hot rolled thin gauge steel strip, a new type of roll contour configuration was developed for a four-high temper rolling mill based on the finite element method analysis. The roll contour configuration consists of a variable contact back-up roll contour and a positive crown work roll contour. Both can be described as sixth order polynomial functions. The variable contact back-up roll not only reduces the roll stack deflection and contact stress concentration between work and back-up rolls, but also increases the control capability of the bending force of the work roll. Positive crown work roll contour is utilised to compensate roll wear and in turn the length of temper rolling schedule can be prolonged. After this roll contour configuration was applied on the temper rolling mill of Qiangang Company of Shougang Group, the flatness of hot rolled thin gauge strip was improved by 10% and the working efficiency was also increased as the length of temper rolling schedule was increased. 相似文献
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In order to simulate and analyze hot strip crown and flatness accurately and efficiently, the 3-D (three-dimensional) coupled model involved in RPFEM (rigid-plastic finite element method) is improved based on the analytical model of forecasting rolling force distribution. In the analytical model, variational method is employed to solve the lateral flow of metal and influential function method is employed to calculate roll deflection, the lateral distribution of rolling force can be obtained rapidly by iterative strategy. Then the 3-D coupled model uses the result as initial distribution of rolling force to calculate roll deflection and makes the initial on-load roll gap profile close to the final value, so as to reduce iterations and increase efficiency. Compared with previous algorithms, the improved model can reduce the iterations by about 50% and shorten the computing time by about 60% on the basis of the calculation accuracy. 相似文献
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为系统分析不同辊形配置下辊间接触压力分布形式与板形调控特性,以某1 800 mm热轧生产线使用的2种典型辊形配置为研究对象,建立对应的辊系有限元模型,计算不同带钢规格与调控手段下辊间接触压力分布形式,分析得出常规凸度支撑辊对应的辊间接触压力分布形式与CVC工作辊辊形呈现出明显的对应性,且压力分布形式受轧制规格与调控手段的影响明显小于CVC支撑辊。利用接触压力峰值和不均匀度表述辊间接触压力分布特征,将不同规格与调控手段对辊间接触压力分布特征的影响进行量化处理,得到更为具体的不同参量在整个变化范围内对分布特征的整体影响趋势。同时还对2种辊形配置下不同辊间接触压力对轧机板形调控特性影响进行分析,得出CVC支撑辊对应辊形配置的弯辊力与窜辊位置在板形调控能力上均强于常规凸度支撑辊辊形配置,而不同辊形配置对辊缝形状的影响表现出较为明显的差异,引入辊间接触压力边中比得到调控特性与辊间接触压力之间的具体关系,并结合现场的实际生产数据对仿真分析结果进行验证,研究结果可为现场辊形配置与板形调控提供较好的理论基础和生产指导。 相似文献
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为系统分析不同辊形配置下辊间接触压力分布形式与板形调控特性,以某1 800 mm热轧生产线使用的2种典型辊形配置为研究对象,建立对应的辊系有限元模型,计算不同带钢规格与调控手段下辊间接触压力分布形式,分析得出常规凸度支撑辊对应的辊间接触压力分布形式与CVC工作辊辊形呈现出明显的对应性,且压力分布形式受轧制规格与调控手段的影响明显小于CVC支撑辊。利用接触压力峰值和不均匀度表述辊间接触压力分布特征,将不同规格与调控手段对辊间接触压力分布特征的影响进行量化处理,得到更为具体的不同参量在整个变化范围内对分布特征的整体影响趋势。同时还对2种辊形配置下不同辊间接触压力对轧机板形调控特性影响进行分析,得出CVC支撑辊对应辊形配置的弯辊力与窜辊位置在板形调控能力上均强于常规凸度支撑辊辊形配置,而不同辊形配置对辊缝形状的影响表现出较为明显的差异,引入辊间接触压力边中比得到调控特性与辊间接触压力之间的具体关系,并结合现场的实际生产数据对仿真分析结果进行验证,研究结果可为现场辊形配置与板形调控提供较好的理论基础和生产指导。 相似文献
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以国内某2 230 mm冷连轧机组六辊CVC轧机为研究对象,利用非线性有限元方法,模拟分析了弯辊和窜辊综合调控下工作辊初始凸度对承载辊缝形状、辊间接触压力分布的影响规律。结果表明,当工作辊采用凸度为0~75 μm的抛物线辊型时,轧机承载辊缝凸度调控域发生平移而面积基本不变,但随着工作辊初始凸度增加,辊间接触压力峰值和不均匀度均有所改善,有利于降低轧辊磨损和辊耗。对比分析了不同板宽条件下的辊缝凸度调节域,结果表明,CVC轧机对宽带钢的板形调控能力要明显高于窄带钢,且对二次、四次板形具有较好的抑制作用,为宽薄带钢冷轧机型选择提供了理论依据。 相似文献
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In order to improve rolled strip quality, precise plate shape control theory should be established. Roll flattening theory is an important part of the plate shape theory. To improve the accuracy of roll flattening calculation based on semi-infinite body model, especially near the two roll barrel edges, a new and more accurate roll flattening model is proposed. Based on boundary integral equation method, an analytical model for solving a finite length semi-infinite body is established. The lateral surface displacement field of the finite length semi-infinite body is simulated by finite element method (FEM) and lateral surface displacement decay functions are established. Based on the boundary integral equation method, the numerical solution of the finite length semi-infinite body under the distributed force is obtained and an accurate roll flattening model is established. Different from the traditional semi-infinite body model, the matrix form of the new roll flattening model is established through the mathematical derivation. The result from the new model is more consistent with that by FEM especially near the edges. 相似文献
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CSP末机架支持辊辊形研究 总被引:1,自引:0,他引:1
针对CSP热连轧F7机架支持辊辊形高、窜辊分布不合理、轧制薄规格时出口板形易出现中间浪、下机磨损不均匀、磨损严重且CVC趋势比较明显等问题,提出与CSP热连轧工作辊辊形相匹配的支持辊新辊形VCR+,采用二维变厚度有限元模型对新辊形的板形控制性能进行了分析,并且在F7机架上进行工业试验。研究结果表明,新辊形VCR+使用后工作辊窜辊分布更加合理,使得出口板形中间浪问题有了明显的改善;轧辊的自保持性能有了显著的提高,从而延长了轧制公里数,降低了生产成本。 相似文献
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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. 相似文献
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