Effectiveness of edge drop control of tapered work roll shifting during tandem cold rolling process
-
摘要: 在冷连轧无取向硅钢薄带过程中，为了实现锥形工作辊窜动自动控制边降，需要合理的确定功效系数与策略。这种系数的获得，不只需要研究本道次的轧辊弹性变形、薄带横向流动、机架间变形对窜辊效率的影响，更重要的是需研究上游机架窜辊对下游机架的影响。这就需要高效的仿真模型来完成以上计算。基于边降区域的金属横向流动理论，建立了将横向流动视为纯剪切增量的数值模型，避免了沿带宽方向建立刚度矩阵，从而提高了计算效率。同时考虑了薄带在机架间发生的轧后屈服流动，由于锥形工作辊窜动，打破了带钢断面的等比例遗传关系，使得轧后带钢在边部区域需要缩宽并减薄来补偿边部延伸率差。所建立的数值模型通过工业现场实验验证，相比于原有模型具有更高的精度。完成了两个机架连续计算，研究了上游机架窜辊对下游机架出口边降的影响。研究发现，第一机架的边降控制范围最宽，第二、三机架控制范围逐渐变窄。根据该规律设计了根据三点边降偏差的配合调控策略，相比单点策略在工业应用中取得了更好效果。Abstract: In the process of tandem cold rolling of nonoriented silicon steel strip, it is imperative to design the control strategy and initial values of the edge drop control efficiency coefficient to achieve automated control in the edge drop by shifting tapered work roll. To obtain these values, intensive modeling is needed to study not only the effects of work roll deformation, metal transverse flow, and inter-stand deformation on tapered work roll shifting at one stand but also the effects of different work roll shifting values at the upstream stand on the edge drop at downstream stand. These intensive calculations have to be performed by an accurate numerical model with a high cost/effective ratio. Based on the metal transverse flow theory at the edge drop zone, a numerical model was built in this study, in which the lateral flow was treated as a pure shear increment inside the rolling region, so that building a stiffness matrix in the lateral direction was not needed and modeling cost was saved. Additionally, inter-stand deformation was considered. Considering the proportional ratio of the strip was broken by the tapered work roll shifting, the longitudinal strain at the strip edge was considerably lower than the strain at the center, which leaded to shrinking and thinning near the edge. It was proved that the coupled model can provide results, which were obtained through industrial experiments, with higher accuracy compared with the original one. Successive calculations of two stands were conducted to reveal the control effectiveness of different tapered work roll shifting values at upstream stand on the downstream stand. It has been observed that the edge drop control region is the widest at the 1st stand, and its width successively reduces at the 2nd and 3rd stands. Based on this rule, a control strategy based on a three-point measure instead of a single point was proposed, and it was proved to be more effective than the one-point measure used in industrial applications.
-
图 1 边降自动控制系统（a）和工作辊窜辊调控功效系数（b）
Figure 1. Schematic of edge drop control system (a) and schematic showing the effectiveness of tapered work roll shifting (b)
图 2 薄带轧制受力与变形分析图。（a） 正视图；（b） 侧视图；（c） 俯视图
Figure 2. Force and deformation diagram of strip rolling: (a) front view; (b) side view; (c) top view
图 4 模型验证。（a） 第一机架计算结果; （b） 第二机架计算结果
Figure 4. Validation of model: (a) results of 1st stand; (b) results of 2nd stand
图 5 锥形工作辊窜辊边降调控功效系数。（a）第1特征点；（b）第2特征点；（c）第3特征点；（d）三点配合调控策略应用效果
Figure 5. Effectiveness of edge drop control of tapered work roll shifting: (a) at measuring Point 1; (b) at measuring Point 2; (c) at measuring Point 3; (d) applied effects of three-point control strategy
表 1 轧制参数表
Table 1. Table of rolling parameters
机架号 入口厚度/mm 压下量/% 后前张力/MPa 摩擦系数 1 2.50 30 15/135 0.085 2 1.80 35 135/140 0.080 3 1.18 31 140/145 0.070 4 0.80 28 145/145 0.060 
下载: 导出CSV
-
[1] 胡强, 王晓晨, 杨荃. 六辊冷连轧机边降自动控制系统设计及应用. 冶金自动化, 2016, 40(1):34 doi: 10.3969/j.issn.1000-7059.2016.01.008Hu Q, Wang X C, Yang Q. Design and application of automatic edge drop control system for 6-high tandem cold rolling mill. Metall Ind Autom, 2016, 40(1): 34 doi: 10.3969/j.issn.1000-7059.2016.01.008 [2] 张岩, 高健, 吴鲲魁, 等. 单锥度辊冷轧机边部减薄控制应用研究. 冶金自动化, 2016, 40(1):45 doi: 10.3969/j.issn.1000-7059.2016.01.010Zhang Y, Gao J, Wu K K, et al. Application research for edge drop control on cold mill of single taper roll. Metall Ind Autom, 2016, 40(1): 45 doi: 10.3969/j.issn.1000-7059.2016.01.010 [3] Cao J G, Chai X T, Li Y L, et al. Integrated design of roll contours for strip edge drop and crown control in tandem cold rolling mills. J Mater Process Technol, 2018, 252: 432 doi: 10.1016/j.jmatprotec.2017.09.038 [4] Lee J S, Shin T J, Yoon S J, et al. Prediction of steady-state strip profile in flat rolling. Steel Res Int, 2016, 87(7): 930 doi: 10.1002/srin.201600032 [5] Pawelski O, Teutsch H. A mathematical model for computing the distribution of loads and thickness in the width direction of a strip rolled in four-high cold-rolling mills. Eng Fract Mech, 1985, 21(4): 853 doi: 10.1016/0013-7944(85)90092-X [6] Jiang Z Y, Wei D, Tieu A K. Analysis of cold rolling of ultra-thin strip. J Mater Process Technol, 2009, 209(9): 4584 doi: 10.1016/j.jmatprotec.2008.10.035 [7] 孙文权, 杨荃, 邵健, 等. UCM冷连轧机硅钢边降控制技术. 北京科技大学学报, 2010, 32(10):1340Sun W Q, Yang Q, Shao J, et al. Edge drop control technique of silicon steel for UCM tandem cold rolling mills. J Univ Sci Technol Beijing, 2010, 32(10): 1340 [8] Ma X B, Wang D C, Liu H M. Coupling mechanism of control on strip profile and flatness in single stand universal crown reversible rolling mill. Steel Res Int, 2017, 88(9): 1600495 doi: 10.1002/srin.201600495 [9] Wang X C, Yang Q, Jiang Z Y, et al. Research on the improvement effect of high tension on flatness deviation in cold strip rolling. Steel Res Int, 2015, 85(11): 1560 [10] 连家创, 段振勇, 叶星. 三维解析法求解辊缝中金属横向流动问题. 燕山大学学报, 1984(3):1Lian J C, Duan Z Y, Ye X. Study of rolling region metal transverse flow by 3 dimensional analytical method. J Yanshan Univ, 1984(3): 1 [11] Le H R, Sutcliffe M P F. A robust model for rolling of thin strip and foil. Int J Mech Sci, 2001, 43(6): 1405 doi: 10.1016/S0020-7403(00)00092-8 [12] Feng X W, Wang X C, Sun J Q, et al. Analysis of tapered work roll shifting technique in 5-stand UCMW tandem cold rolling process [J/OL]. Australian Journal of Mechanical Engineering (2019-04-23) [2019-06-01]. https://doi.org/10.1080/14484846.2019.1606762 [13] 管健龙, 何安瑞, 孙文权. 薄铝带轧制工作辊边部接触的建模与仿真. 东北大学学报: 自然科学版, 2015, 36(7):942Guan J L, He A R, Sun W Q. Modeling and simulation of thin aluminum cold rolling with work roll edge contact. J Northeast Univ Nat Sci, 2015, 36(7): 942 [14] 刘立文, 张树堂, 武志平. 张力对冷轧板带变形的影响. 钢铁, 2000, 35(4):37 doi: 10.3321/j.issn:0449-749X.2000.04.010Liu L W, Zhang S T, Wu Z P. Influence of tension on the deformation of strip during cold rolling. Iron Steel, 2000, 35(4): 37 doi: 10.3321/j.issn:0449-749X.2000.04.010 [15] Hacquin A, Montmitonnet P, Guillerault J P. A steady state thermo-elastoviscoplastic finite element model of rolling with coupled thermo-elastic roll deformation. J Mater Process Technol, 1996, 60(1-4): 109 doi: 10.1016/0924-0136(96)02315-1 -
点击查看大图
图(5) / 表(1)
计量
- 文章访问数: 867
- HTML全文浏览量: 724
- PDF下载量: 49
- 被引次数: 0
