成功解决冷轧带钢表面"锈斑"的冷轧带钢平整线

分析了冷轧带钢表面"锈斑"产生的原因,并设计了一种新型的冷轧带钢平整生产线,通过在机组中设置新型挤干机及挤干辊,在不破坏带钢表面质量的同时清除带钢表面残留的平整液,避免了带钢表面因沾染水分而生锈的情况,提高了带钢表面的外观质量.     

板带钢头部翘曲的有限元分析

为了减轻轧件头部翘曲给轧制过程带来的影响,根据现场轧制工艺,采用弹塑性有限元法建立了三维非对称轧制有限元模型。利用该模型分析热轧板带钢生产过程中轧件头部翘曲的产生机理,并研究了不同轧制工艺下的辊速比、上下表面温差、不同摩擦系数对轧件头部翘曲的影响规律。结果表明,随着压下量的增大,轧件头部翘曲量的增大趋势减缓,采用不同的配辊方案（异径比）可控制其头部翘曲的现象。     

WRS轧机工作辊磨损计算及板形调控分析

在热带钢连轧机设计及改造中采用WRS辊系作为下游机座可以增强机组的板形调控能力。从理论上分析了辊系在轧制中的磨损特性，工作辊磨损辊型的计算方法，根据实际轧制工况对其板形的调控、影响因素进行了定量分析。     

CAPL平整工艺参数合理化研究

本文以Ｂｌａｎｄ－Ｆｏｒｄ—Ｈｉｌｌ理论公式为基础构造了半经验平整轧制为模型，在模型中，以Ｈｉｔｃｈｃｏｃｋ所提出的两个圆柱体接触的变形理论来确定变形区长度，模型反映了带钢变形抗力、外摩擦及带钢张力对轧制力的影响。据此模型，本文给出了平整轧制力及张力设定规范。     

有高温相变的电工钢热轧起浪的有限元分析

针对电工钢自由规程轧制过程起浪问题,开展电工钢不同冷却条件下的连续冷却相变转变温度分析测定和Gleeble热模拟实验,发现电工钢在975~875℃的奥氏体-铁素体两相区,随着轧制温度降低,变形抗力反而减小;电工钢大量同宽自由规程轧制下的工作辊出现严重的不均匀的箱型磨损和明显的热胀,综合辊形变化显著.考虑电工钢两相区变形抗力差异和综合辊形变化,建立电工钢热轧过程轧辊轧件的三维弹塑性耦合有限元模型,仿真分析轧制力、弯辊与窜辊对承载辊缝形状的影响,研究摩擦系数、压下量与轧制速度对带钢宽度方向内应力变化规律的影响,采用Shohet板形判据确定电工钢比例凸度残差变化路径,明确电工钢在"平坦死区"较大的上游机架出现"异常起浪"的生成过程.该方法为电工钢热轧板形的浪形控制提供了依据.     

非对称轧制力能参数与带钢张应力分布规律

为深入了解带钢轧制过程中非对称因素对轧制力能参数与带钢张应力分布的影响,应用ABAQUS非线性有限元软件对轧制过程进行二维建模及仿真分析,以轧辊驱动方式非对称、上下工作辊与带钢间接触摩擦润滑条件非对称以及存在异步轧制等3种非对称因素作为研究对象,计算并分析上述非对称因素及其程度对于轧后带钢内部张应力分布、轧制力以及轧制扭矩的影响规律,进而定量分析与比较3种非对称轧制因素对于轧制过程中的力能参数和厚向张应力分布规律的影响程度. 仿真计算表明：3种非对称轧制状态都会导致轧后带钢厚向张应力分布的不对称;3种非对称轧制状态都会明显改变轧制过程力能参数大小;与相应对称轧制状态相比,有些非对称因素可以不同程度地降低轧制力和轧制扭矩. 轧制过程中的非对称因素从不同的角度来分析,是利弊共存的.     

异步冷轧轧制力矩的理论及实验分析

用辊系力矩分析法，建立了支持辊传动四辊冷轧机异步轧制轧制力矩的理论计算结构式，并对异步冷轧轧制力矩特性进行了生产实验分析，为异步工艺在冷轧带钢生产中的应用提供了理论及实验依据。     

1780热连轧机轧辊的动力学分析

以1780热连轧机机组第五架轧机在轧制过程中发生振动为背景,建立轧辊三维模型,利用ANSYS软件对其进行动力学分析,计算出工作辊和支承辊的各阶模态参数。工作辊的第3阶和第11阶振型纵向变形较大,造成较大辊缝,对轧制厚度影响最大;支承辊的第1阶和第7阶振型轧辊纵向位移明显,五倍频振动是带材或轧辊表面产生明暗条件原因。     

连续铸轧辊套传热分析

在连续铸轧中，金属液经铸嘴装置连续不断地注入2个相向旋转，内部通水冷却的铸轧辊的辊缝中间，金属液在辊中冷却，凝固结晶并经轧制成形，作者通过建立铸坯与铸轧辊辊套之间强温度耦合特性的界面接触热导模型及铸坯和铸轧辊辊套传热数学模型，对铸轧辊与铸坯的温度场进行了仿真，并分析了辊套的厚度，导热系数和表面粗糙度对辊套温度分布的影响，通过仿真分析发现：辊套外表面温度在铸轧区变化剧烈，辊套进入铸轧区入口处温度开始急剧上升，但最高温度并不在出口,而是在轧制区靠近出口,辊套离开铸轧后温度开始下降，进入入口处时温度降至最低；界面导热能力随辊套表面粗糙度减小，辊套材料的导热系数增大，辊套厚度减小而增大。     

尼龙66低旦丝用细面牵伸辊的开发和应用

对尼龙66低旦丝一步法连续聚合纺丝过程中使用的牵伸辊表面粗糙度进行研究,对比不同粗糙度的牵伸辊对低旦丝物理性能和可纺性的影响,探索最佳表面粗糙度的牵伸辊.实验证明,采用表面粗糙度Ra值为3.0μm的细面牵伸辊,低旦丝质量得到优化,毛丝现象明显改善,同时提高了产品得率.     

Improvement on strip flatness of cold temper mills by modifying roll contour shape

A study on roll gap profile (strip profile) control was accomplished in a 1700 mm single-stand temper mill. Some critical problems such as the deviation of work roll contour caused by grinding and wear, the effectiveness of work roll bending were discussed. Using a finite element model, the effects of roll contours (ground and wear) on strip profile were investigated. The roll bending effect on strip thickness was also analyzed. It is pointed out that there are some special features of flatness control in the temper mill: during temper rolling, roll deformation is slight due to small rolling load, and the loaded roll gap profile mainly depends on work roll contour, while the backup roll has a little effect on gap crown; the effect of bending force on gauge can not be ignored due to the coupling between flatness control and gauge control. A new roll contour arrangement adaptable to the mill was presented and has been put into practical production. The application of the new set of rolls showed some good results: larger crown control range of work roll bender, higher rolling stability, better strip profile and flatness quality.     

平整延伸率对Ti-IF冷轧带钢力学性能的影响

冷轧带钢的力学性能与退火后的平整工艺有关。通过对Ti-IF带钢不同延伸率的试验研究,找出平整延伸率对力学性能影响关系,有利于指导生产和产品性能的稳定控制。     

Preset model of bending force for 6-high reversing cold rolling mill based on genetic algorithm

The hydraulic roll-bending device was studied, which was widely used in modern cold rolling mills to regulate the strip flatness. The loaded roll gap crown mathematic model and the strip crown mathematic model of the reversing cold rolling process were established, and the deformation model of roll stack system of the 6-high 1 250 mm high crown (HC) reversing cold rolling mill was built by slit beam method. The simulation results show that, the quadratic component of strip crown decreases nearly linearly with the increase of the work roll bending force, when the shifting value of intermediate roll is determined by the rolling process. From the first pass to the fifth pass of reversing rolling process, the crown controllability of bending force is gradually weakened. Base on analyzing the relationship among the main factors associated with roll-bending force in reversing multi-pass rolling, such as strip width and rolling force, a preset mathematic model of bending force is developed by genetic algorithm. The simulation data demonstrate that the relative deviation of flatness criterions in each rolling pass is improved significantly and the mean relative deviation of all five passes is decreased from 25.1% to 1.7%. The model can keep good shape in multi-pass reversing cold rolling process with the high prediction accuracy and can be used to guide the production process.     

油介质下轮轨粘着特性数值分析-研究生论坛

基于二维滚动接触理论和部分弹流理论,建立了微凸体接触情况下的稳态部分弹流数值模型,运用多重网格法对油介质工况下的轮轨黏着特性进行数值仿真研究。利用所建立的数值仿真模型研究了轮轨接触压力分布情况,分析了滚动速度、载荷、轮轨表面粗糙度等参数对轮轨黏着特性的影响。结果表明:油介质条件下轮轨接触区的宽度比干态下要宽,是干态下接触区宽度的1.5倍左右;油介质下的轮轨黏着系数明显小于干态下的黏着系数;轮轨黏着系数随着速度的增加逐渐减小,随接触压力的增加而降低,随轮轨表面粗糙度的增加而增大。     

Thermal contact conductance at continuous roll-casting interface

The effects of surface roughness, strain rate, friction coefficient and pressure on real contact area were analyzed based on the research of Stupkiewicz. The real contact area model taking account of the effect of friction and deformation of material was obtained. The model of contact conductance at the rolling interface was obtained by integrating the specific feature of heat transfer through the interface of continuous roll-casting. The results indicate that the real contact area increases obviously when the material is under yield, and the real contact area varies inversely with surface roughness, whereas it varies exponentially with friction coefficient, strain rate and pressure, and the power factor depends on strain rate.     

Analysis of the thermal profile of work rolls in the hot strip rolling process

A 2-dimension axisymmetric model was developed by the finite-difference method, which can be used to predict the transient temperature field and thermal profile of work rolls in the hot strip rolling process. To demonstrate the accuracy and reliability of the solution developed, the calculation results were compared with the production data of a 1700 mm hot strip rolling mill and good agreement was found between them. The effect of strip width and roll shifting on the thermal expansion of the work rolls was studied.It is found that the strip width has marked effect on the efficient thermal crown. Initially, when the rolling strip changes from narrow to wide, a bigger efficient thermal crown can be quickly achieved; afterwards, when the rolling strip changes from wide to narrow,not only the influence of uneven wear can be reduced but also the excessive efficient thermal crown can be avoided. It is also found that the work roll shifting has a determinate but not obvious effect on the reduction of the efficient thermal crown, and will make the strip shape unstable without being used properly.