冷轧高强钢内浪产生的原因及控制

结合平整机的结构特点和平整工艺板形控制过程，分析了冷轧高强钢平整过程中内浪产生的原因，并提出了改进措施。认为，原料、设备、张力、工作辊是内浪缺陷产生的主要原因。通过提高原料质量、增加设备精度、稳定张力和分类使用工作辊等措施，减少了内浪的产生，工作辊的磨削数量由原来的80套/月降为30套/月，节约生产成本约10万元/月。同时提高了冷轧平整工艺的生产稳定性和产品合格率。     

针对冷轧中间浪的热轧带钢凸度分析与控制

针对某钢厂冷轧工序电镀锌等钢种表现出的中间浪板形缺陷，通过长期的跟踪对比分析，认为电镀锌钢种冷轧中间浪缺陷与热连轧生产线的热轧带钢板廓凸度有关。为明确热轧带钢凸度与冷轧中间浪之间的对应关系，统计分析了热轧带钢凸度情况，表现出冷轧中间浪问题的热轧带钢凸度值C₄₀均为50μm以上，而且现场实际生产的热轧带钢C₄₀大于50μm的比例达到了44.07%,因此提出热轧带钢C₄₀过大是产生冷轧中间浪的一个主要原因；分析了热轧凸度仪数据处理计算过程对实测凸度值的影响规律，并将凸度仪的在线测量值与人工离线测量值进行对比，发现离线测量凸度均大于在线测量凸度，偏差平均值为10μm左右，因此提出热轧现场凸度仪因数据处理过程中存在的误差，导致实际生产的带钢凸度较测量值偏大是产生冷轧中间浪的另一个主要原因。针对热轧产品凸度过大，综合生产稳定性、改进过渡性原则，提出了将原凸度目标50μm设定为30μm的“小凸度”控制策略，并投入工业生产实践，热轧带钢凸度得到有效控制。分别连续统计实施“小凸度”轧制策略前后各5个月的实际生产数据，发现电镀锌钢种因存在...     

铜市酝酿中级别调整

铜市正在酝酿中级别调整金融危机后期,即2008年12月见底2825美元/吨以来,LME铜市演绎了经典的A-B-C三浪反弹,以波浪理论分析,可看作是2001年11月1336美元/吨为起点的历时55个月超级牛市的调整浪二浪之b浪,而a浪下跌始于2006年5月的8675美元/吨,a与b分别用时31个月和26个月,整个二浪属于强势平台调整型。目前,LME铜市处于c浪下跌初期,预计其用时大概需要22个月(可能在2012年12月结束),将主要运行于10160美元/吨     

支撑辊阶梯辊型技术的应用试验

本文介绍了阶梯辊型技术在秦皇岛板材公司的应用试验情况，其中阐述了试验内容和方法，检测和分析了板凸度、辊型磨损等数值。结果表明，支撑辊Ｌ－２７０ｍｍ阶梯辊型型技术的应用在改善板型、减少轧型浪型废品方面效果显著。     

强化质量意识注重企业管理

强化质量意识注重企业管理无锡县雪浪初轧厂无锡县雪浪初轧厂于１９８７年开始筹建，自筹资金１６５０万元，仅用了不到一年的时间，创建了以６３０×３横列式轧机为主体、配套设施齐全、年生产能力为３０万吨的中型冶金企业。建厂以来，我们始终坚持“以质量求生存，以技...     

莱钢大型H型钢腹板浪原因分析与控制

介绍了莱钢大型H型钢热轧腹板浪和冷却腹板浪产生的原因,并制定了相应的解决措施。     

简论社会思潮与弘扬民族精神

如果说社会生产和日常生活是深层的水流,那么社会思潮作为水流奔腾所形成的浪花,民族精神作为历史长河中所形成的涛浪.虽然浪花引人注目,涛浪激荡心灵,但它们往往表面现象转瞬即逝的;相反支持浪花、涛浪的深层水流才是根本的存在.     

热轧带钢单边浪控制与调整

主要介绍了热轧带钢轧制过程中的辊缝状态、坯料楔形、坯料宽度方向上温度不均、坯料板形不良、轧机入口导板不对中、轧辊两侧磨损不均、飞剪切头切尾不干净、轧机机座两侧刚度系数不同等导致带钢产生单边浪的原因,并对减小带钢单边浪提出了相应的控制措施和方法,以提高热轧带钢产品的质量。     

极薄带钢用串列式冷轧机自动板形控制系统的开发

近年来，随着冷轧钢板板厚更薄及要求板形质量更好，迫切要求确立冷轧机高粗度平坦度（板形）控制技术。在以轧制极薄带钢为主的千叶钢铁厂第一冷轧车间的６机架串列式冷轧机上，１９８８年４月设置接触辊式板形传感器，从而开发了自动板形控制系统。根据详细的模拟结果，终端控制选择了工作辊正负弯辊以及可改变板宽方向冷却剂流量分布的局部冷却控制。通过采用本系统，不仅可控制纯边浪和中浪，而且还可控制复杂的波浪分布。其结果     

船舶参数激励横摇运动研究综述

为避免参数激励导致船舶出现不稳定横摇,提出有效抑制参数横摇的方法.分析参数激励引起的大幅横摇运动的动力特性,从船舶非线性耦合运动、横浪运动、纵浪上参数激励运动和波浪上参数与波浪联合激励运动方面,对目前研究现状及取得的主要成果进行综述,对船舶参数激励横摇运动及其倾覆机理的研究前景进行展望.     

轧制带材的屈曲理论及其在冷轧机板形控制中的应用

本文首次应用薄板稳定理论求解了轧制带材各种复杂模态的在线屈曲临界域和瓢曲浪形成路径，成为正确的板形力学判据，它是在板形控制系统中建立控制目标设定模的理论基础，并在宝钢２０３０ｍｍ冷轧机中得以成功应用。     

3#电工钢机组带钢板形的控制与改善

冷轧电工钢产品除了对磁性能有较高需要外,对带钢的浪形也有很高的要求.电工钢连续退火涂层机组由于退火温度高,带钢在退火过程中会产生浪形,严重时会影响产品的正常使用.在分析带钢浪形的影响因素的基础上,3#电工钢机组采用控制带钢冷却速度、改进缓冷段风箱结构和挡板控制方式、减少退火炉入口带钢跑偏等措施来控制浪形的发生.在生产过程中,取得了良好的浪形控制效果.     

珠钢平整机带头平整功能开发及应用

针对薄规格产品的浪形情况和平整机平整带钢头尾浪形所存在的缺陷等问题，珠钢自主开发了平整机带头平整程序，实现了平整机带头的平整功能，改善了产品的质量，提高了经济效益。     

Physical and Numerical Simulation of Fluid Flow and Solidification at the Twin‐Roll Strip Casting Process

The fluid flow in a twin‐roll strip caster is investigated by physical and numerical simulation on a 1:1‐scale water model. A laser‐optical measurement technique (Laser Doppler Anemometry ‐ LDA) is used to validate the numerical results for the water flow. The numerical simulations are then transferred to the melt flow in the strip caster. The investigations are focused on different SEN concepts (submerged entry nozzle), a single‐nozzle system with two outlet ports and a double‐nozzle system with one outlet port each. The Influence of these concepts on the velocity, turbulence, and temperature distribution inside the liquid pool between the casting rolls and on the solidification and growth of the strip shells are investigated by numerical simulations (Computational Fluid Dynamics ‐ CFD). The non‐isothermal melt flow is calculated considering the solidification enthalpy as well as the behaviour of the solidifying melt. In addition to the numerical simulations of the melt flow inside the pool the temperature distribution in the cast strip is simulated. The SEN concept directly correlates with the temperature distribution Inside the strip. Furthermore, the surface temperature of the strip below the outlet of the roll gap is measured using a line‐scanner and is compared with the CFD simulation. In order to simulate the shape of the free surface in the liquid pool, CFD simulations of the water flow in the physical model are carried out using a Volume of Fluid model (VoF). This two‐phase model is able to reproduce free surface waves.     

Nonlinear Spline Finite Element Method for Ribbing of Cold-Rolled Coils

 The ribbing problem has serious influence on the steel product quality, which produces additional shape waves on the surface of uncoiled steel strip on the process of curl. Nonlinear spline finite element method (n-spline FEM) is adopted to establish the relationship between the ribbing height and deflection of additional shape wave, for example, post-buckling deformation. The proposed spline FEM is more effective and convenient than traditional finite element method in the buckling analysis. Using the spline FEM, the shape wave caused by the ribbing is calculated, and then the ribbing values can be obtained which are difficult to measure in practice. At the same time, the judgment rule is also given for estimating the strip quality according to the ribbing value.     

A 2.5-dimensional Analytical Model of Cold Leveling for Plates with Transverse Wave Defects

Waves occurring in cold-rolled plates or sheets can be divided into longitudinal and transverse waves. Classical leveling theories merely solve the problem of longitudinal waves, while no well accepted method can be employed for transverse waves. In order to investigate the essential deformation law of leveling for plates with transverse waves, a 2.5-dimensional(2.5-D) analytical approach was proposed. In this model, the plate was transversely divided into some strips with equal width; the strips are considered to be in the state of plane strain and each group of adjacent strips are assumed to be deformation compatible under stress. After calculation, the bending deformation of each strip and the leveling effect of overall plate were obtained by comprehensive consideration of various strips along with the width. Bending of roller is a main approach to eliminate the transverse waves, which is widely accepted by the industry, but the essential effect of bending of roller on the deformation of plates and the calculation of bending of roller are unknown. According to the 2.5-D analytical model, it can be found that, for plates, it is neutral plane offsetting and middle plane elongation or contraction under inner stress that can effectively improve plate shape. Taking double side waves as an example, the appropriate values of bending of roller were obtained by the 2.5-D analytical model related to different initial unevenness, which was applicable to the current on-line adjusting of bending of roller in rolling industry.     

Influence of roll with cone defect on shape in a six-high mill and its control model

Cone defect in rolls may be caused by bad grinding. Cone defect leads to shape defect in unilateral waves of the finished strip. By using a six-high mill as example and by considering the features of the devices and technology, an influence model of roll with cone defect and a suitable shape control technology of a six-high mill was established to guarantee good shape. This model was then applied to a production practice of 1220 cold continuous rolling units. Quantitative analysis of different kinds of roll with cone defect and its effect on shape control shows that the additional shape caused by cone defect are unilateral waves. In conclusion, optimising the amount of tilt settings can effectively control the additional shape caused by cone defect, which provides enterprises with a useful reference for the high-precision control of shape.     

辊式矫直机矫直板带浪形的有限元仿真分析

 辊式矫直机的矫直功能是中厚板生产线上保证板带板形的重要手段,其矫直过程可以消除或均匀板带内部残余应力,对提高板带综合质量具有重要意义。为了分析矫直机对带有边浪的板带的矫直过程以及矫直效果,首先建立了板带弯曲挠度的计算模型,为确定矫直辊的压弯量奠定了基础。在矫直模型作为压弯量设定的基础上,参考现场实际设备尺寸,通过借助大型商用有限元软件ANSYS建立了11辊的辊式矫直机有限元仿真模型,并针对研究目标设计了相应的仿真工况,将模型的矫直过程调整为采用上辊系整体压下倾斜的设置,对不同浪高的板带进行仿真分析。将有限元模型计算出的矫直力与生产实际设备的矫直力进行对比,有限元模型的矫直力计算偏差约为8.3%,满足计算精度要求。设置边浪浪高分别为5、10、20 mm的板带作为仿真工况,对其矫直过程进行仿真计算,提取仿真结果中的相关数据进行分析,发现在不采用弯辊的条件下,矫直过程同样具有消除板带不平度的作用。结果表明,在浪高较大时,矫直过程消除不平度的作用明显,但是矫直后板带并不能达到最终的平整度要求;在浪高较小时,矫直过程对不平度的消除能力较弱,但矫直后板带不平度可以达到最终的平整度要求。在分析的基础上,在工业现场的实际设备中进行相关试验,试验数据表明,仿真结果与试验结果趋势相同。     

Oblique and Herringbone Buckling Analysis of Steel Strip by Spline FEM

 The tilted waves in steel strip during rolling and leveling of sheet metal can be classified into two different types of buckling, oblique and herringbone buckling, respectively. Numerical considerations of oblique and herringbone buckling phenomena are dealt with by the spline finite element method (FEM). It is pointed out that the shear stress due to residual strains caused by the rolling process or applied non-uniform loading is the main reason of oblique and herringbone buckle. According to the analysis of stress distribution in plane, the appropriate initial strain patterns are adopted and the corresponding buckling modes are calculated by the spline FEM. The developed numerical model provides an estimation of buckling critical load and wave configuration.