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.     

纳米添加剂对板带钢冷轧乳化液润滑性能的影响

通过四球摩擦学试验分析纳米添加剂对板带钢冷轧乳化液摩擦学性能的影响;在不同润滑条件下进行冷轧试验,分析纳米添加剂对冷轧过程和轧后带钢表面质量的影响。结果表明,含纳米添加剂的轧制乳化液与传统轧制乳化液相比,其承载能力和抗磨减摩性能均有所改善;带钢冷轧过程中采用含纳米添加剂的轧制乳化液进行润滑,可有效降低轧制压力和轧机功率、减少能耗,并且轧后带钢表面质量也有明显改观。     

冷轧带钢板形测量信号的有效补偿处理方法

针对冷轧带钢板形测量信号的补偿处理问题,通过数学模型分析和仿真验证的方法进行了研究和优化设计.所提出的板形测量信号补偿处理方法可以有效消除外界因素对测量信号产生的影响,为板形控制系统提供高精度的板形信号以用于提高板形控制精度,满足高精度板形控制的需要.仿真研究验证了该测量信号补偿方法的有效性和先进性.     

Lubrication in strip cold rolling process

A lubrication model was developed for explaining how to form an oil film in the deformation zone, predicting the film thickness and determining the characteristics of lubrication in the strip rolling process, combined with the knowledge of hydrodynamic lubrication and rolling theories. Various mineral oils with viscosities from 0.032 to 1.6 Pa.s were used to obtain different film thicknesses in the strip cold rolling. Results from the experiment and calculation show that the oil film forming in hydrodynamic lubrication is up to the bit angle and a higher rolling speed or a higher rolling oil viscosity. The mechanism of mechanical entrainment always affects the film thickness that increases with the rolling oil viscosity increasing or the reduction rate decreasing in rolling.     

Dynamic characteristics of cold rolling mill and strip based on flatness and thickness control in rolling process简

The dynamic model of cold rolling mill based on strip flatness and thickness integrated control was proposed,containing the following sub-models：the rolling process model,the dynamic model of rolls along axial direction,and the compensation model.Based on the rule of volume flow rate,the dynamic rolling process model was built.The work roll and backup roll were taken as elastic continuous bodies,the effect of shear and moment of inertia were taken into consideration,and then the dynamic model of rolls was built.The two models were coupled together,and the dynamic model of rolling mill was built.In the dynamic model,the thermal expansion of the rolls,the wear of the rolls and other related parameters can not be considered.In order to compensate the dynamic model,the coupled static model of rolls and strip was applied.Then,according to the inner relationship of these models,the dynamic model and the compensation model were coupled,and the dynamic model of rolling mill based on the strip flatness and thickness integrated control was built.The dynamic simulation of the rolling process was made,and the dynamic thickness and the dynamic flatness information were obtained.This model not only provides a theory basis for the virtual rolling,but also provides a platform for the application of advanced control theory.     

Strip shape control capability of hot wide strip rolling mills

The elasticity deformation of rolls was analyzed by means of two-dimensional finite element method （FEM） with variable thickness. Three typical mills were used as objects for analysis. A thorough study was done on the control capabilities of these mills on the strip shape. Then the strip shape control capabilities of the three mills was compared synthetically. 2008 University of Science and Technology Beijing. All rights reserved.     

Analysis of the cause of crack in cold rolling of QSn6.5-0.1 strip

ＱＳｎ6 .5 0 .1ｃｏｐｐｅｒａｌｌｏｙ,ｔｈｅｍｏｓｔｉｍｐｏｒ ｔａｎｔｅｌａｓｔｉｃｍａｔｅｒｉａｌ,ｈａｓｂｅｅｎｕｓｅｄｆｏｒｐｒｏｄｕｃｉｎｇｓｐｒｉｎｇｓａｎｄｓｗｉｔｃｈｅｓｅｔｃ .ｄｕｅｔｏｉｔｓｅｘｃｅｌｌｅｎｔｍｅ ｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ[1 3] .Ｈｏｗｅｖｅｒ,ｄｕｒｉｎｇｃｏｌｄｒｏｌｌｉｎｇ,ａｌａｒｇｅｎｕｍｂｅｒｏｆｃｒａｃｋｓｏｃｃｕｒｒｅｄａｎｄｃｏｎｃｅｎｔｒａｔｅｄｏｎｔｈｅｏｕｔｓｉｄｅｓｕｒｆａｃｅ .Ｃｅｒｔａｉｎｌｙ ,ｔｈｅｒａｔｅｏｆｐｒｏｄｕ…     

板形控制技术探讨

介绍带钢板形控制技术，比较其特点及应用情况，总结板形控制技术及理论成果；展望板形控制技术的发展方向，为进一步促进该技术的研究提供参考。     

Backup roll contour of a SmartCrown tandem cold rolling mill

SmartCrown was a new system developed by VAI for improving the strip profile and flatness control first applied in 1700mm tandem cold rolling mills at Wuhan Iron & Steel (Group) Corporation (WISCO). After tracing and testing, the application of the conventional crown backup roll matching the SmartCrown work roll of the production mill led to heavy and nonuniform wear, and the edge spalling of the backup roll often occurred. A 3-dimension finite element model of roll stacks was established, which was used to analyze the above-mentioned problems, and it was found that the main reason was the highly nonuniform contact pressure distribution between the work roll and the backup roll. A new FSR (flexible shape backup roll) was developed and applied in 1700mm tandem cold rolling mills. A lot of good actual effects of FSR, such as evident improvement in profile and flatness of strips,non-occurring edge spalling, wear uniform, and remarkable decrease in roll consumption were validated by long-term industrial applications.     

冷轧带钢板形屈曲变形失稳限的有限元分析

采用ANSYS有限元仿真分析方法研究冷轧宽带钢板形屈曲失稳特性。利用ANSYS的几何非线性求解模块，建立宽薄带钢二维有限元模型，分析不同形式载荷、厚宽比和张应变下的屈曲失稳过程，计算板形屈曲变形失稳限。分析结果表明：边中复合浪的临界失稳载荷最大，中浪的较大，边浪的最小；边中复合浪的屈曲半波长为板宽的50％-60％，中浪与单边浪为80％左右，对称双边浪约为70％；在同样载荷下，随着厚宽比或张应变的增加，临界失稳限呈增长趋势，并且复杂浪形的临界失稳限增长速度明显大于简单浪形的增长速度。     

Study and application of crown feedback control in hot strip rolling

Crown feedback control is one part of the automatic shape control （ASC） system. On the basis of large simulation researches conducted, a linear crown feedback control model was put forward and applied in actual strip rolling. According to its successful op- eration in the ASP 1700 hot strip mill of Angang Group for one year and also from the statistical results of several crown measurements, it can be definitely said that this control model is highly effective and shows stable performance. The control effectiveness of different gauges of strips with the feedback control is found to increase by 10%-30% compared with that without feedback control.     

基于DSP的三相光伏并网发电系统研究

光伏发电设备接入电网会对电力系统的稳定性产生影响.以光伏并网发电系统为研究对象,基于数字信号处理器(DSP)控制的光伏并网逆变器的工作原理,探讨了LCL滤波器的设计,给出了参数的设计方法和设计步骤.同时研究了并网过程中的软件锁相环技术,对锁相环电路的组成、工作原理进行了探讨.     

冷轧界面油膜厚度对表面形貌转印过程的影响

为研究冷连轧过程中接触界面润滑油膜厚度对表面形貌转印过程的影响,在跟踪实际生产中带钢表面形貌的基础上,结合轧辊表面磨损形貌以及润滑分析确定的界面油膜分布,建立真实表面接触的带钢形貌生成模型,用跟踪测量轧辊服役期内生产带钢表面的粗糙度对模型进行验证.利用模型分析在不同磨损状态下电火花毛化轧辊油膜厚度对转印形成带钢表面形貌的影响规律.结果表明:轧辊表面处于不同磨损状态时,带钢表面Ra的转印率随着油膜厚度的增加而减小;轧辊表面磨损后转印形成的带钢表面P_c的转印率在油膜厚度增加的初期基本保持不变,而后急剧减小.     

基于ＤＳＰ的Ｌｉｕ混沌系统的实现

介绍了一种用DSP实现Liu混沌系统的方案.采用TMS320F2812和DA转换芯片TLC7528C作为工具,将Liu系统离散化后用DSP进行迭代计算,再进行DA转换,输出到示波器上得到相图,并与Matlab仿真结果比较,证明了该方法的正确性.使用该方法不仅观察到了数字电路中的混沌现象,应用到实际中还可与其他数字器件完好地对接,拓宽了混沌理论的应用领域.     

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.     

热连轧带钢负荷分配法的进展

综述了热连轧带钢生产中负荷分配方法的发展,阐明了各种分配方法的优缺点,为热连轧精轧机组合理分配各机架的压下量提供了参考,并叙述了热连轧负荷分配的发展方向。     

Compound control for speed and tension multivariable coupling system of reversible cold strip mill

To weaken the nonlinear coupling influence among the variables in the speed and tension system of reversible cold strip mill, a compound control (CC) strategy based on invariance principle was proposed...     

1420 mm轧机板形预设定计算仿真系统设计

为了提高板形预设定计算的精确度,针对某厂1420 mm冷连轧机板形控制系统的预设定计算模型进行仿真计算.将板形预设定模块从原Solaris系统移植到Windows模拟机上,建立数据信号输入和输出接口,实现板形预设定离线模拟计算,为板形设定计算提供研究和开发平台.其预计算结果的精确度与实际测量值十分相近,直接影响到基础自动化层(L1)的控制,最终提高了带钢板形的质量.     

板带轧制断面形状调节的影响规律研究

为了分析各种断面形状调节手段对各次断面形状的影响规律,以HC轧机为例,以倾辊、工作辊弯辊、工作辊非对称弯辊和中间辊横移作为断面形状调节手段,按照机理模型计算了各调节手段对1次、2次、3次和4次断面形状的影响系数,系统地揭示了各种调节手段对各次断面形状的影响规律,为断面形状在线控制模型的建立、实现提供了基础。     

基于DSP的数字信号采集处理系统设计

为快速准确地采集各种数据，提出一种基于DSP的数字信号处理方法．系统采用DSP作为主处理芯片，外围电路由FPGA实现．多路高速数据使用并行方式进行采集，利用DSP高速处理能力对数据进行处理，最后通过在FPGA内部实现的UART电路与模拟串行口完成数据传输．利用DSP FPGA设计的数字信号处理系统，具有与其他以现代数字技术为基础的设备接口方便、系统精度高、工作可靠的优点．