电动压下多轧程优化规程的实现

论述了多轧程电动压下生产过程中，采用综合等储备原理计算优化规程，进行板宽和板厚控制的可行性及其效果，通过安钢２８００ｍｍ轧机上的工程实践，证明该方法是行之有效的。

型钢全轧程仿真软件的开发与应用

型钢轧制是一个连续的过程,单工序仿真分析存在效率低、精度差的问题。针对单工序仿真存在的不足,通过捕捉模型拓扑关系特点,进行了温度继承、轮廓提取等关键技术的研究,开发了型钢全轧程仿真分析软件。统计表明,单工序仿真分析其前处理时间是全轧程仿真分析软件的10倍左右,与现场实际结果相比,形状误差为8%-10%,轧制力误差为35%-40%,而全轧程仿真分析软件的形状误差为3%-5%,轧制力误差为5%-10%。该软件在现场得到广泛应用,解决了诸多型钢质量难题,降低了型钢产品开发难度。

簿钢带冷连轧一次轧程探讨

本文介绍了上海第十钢铁厂对薄钢带从二次轧程简化成一次轧程的生产探讨,实验证明一次轧程中间不退火轧制极薄带钢是可行的。

热轧带钢轧制全程三维热力耦合仿真分析

通过三维热力耦合弹塑性有限元方法,对1250mm×20mm热轧带钢整个轧制过程进行了仿真分析。介绍了轧制过程分段处理方法及边界条件的设置,获得了轧制全程的轧件温度场及变形结果。通过温降曲线与现场的测试数据进行对比,仿真分析结果与现场实际情况基本吻合,能够为实践生产提供理论参考。

冷轧退火工艺对铁素体不锈钢抗起皱性能的影响

研究了两种不同冷轧退火工艺对铁素体不锈钢的力学性能、织构和抗起皱性能的影响。结果表明:在87%的冷轧压下率单轧程后,25%预拉伸的起皱高度为27.69μm;当总压下率保持不变时,采用双轧程的铁素体不锈钢在25%预拉伸后起皱高度为15.08μm,比单轧程明显降低。在分析再结晶织构后发现:单轧程退火后生成了强γ织构,峰值较高;而双轧程退火后γ织构较为均匀,没有产生明显的强点,峰值也较低。力学性能分析表明,单轧程的平均塑性应变比r值为1.48,平面各向异性参数Δr值为0.46,双轧程能获得更高的r值和Δr值,分别为1.70和0.97。

65Mn优质冷轧钢带的试制与开发

文章主要介绍了包钢钢联一轧厂通过对65Mn优质冷轧钢带的开发与生产,拓宽了冷带产品品种,优化了产品结构。并对65Mn优质冷轧钢带生产开发过程中的轧制工艺、退火工艺制度的制定及产品检验结果分析进行了详细阐述,总结出了65Mn优质冷轧钢带的生产工艺制度。

SUS430铁素体不锈钢冷轧工艺研究

为了减轻采用二轧程工艺生产SUS430不锈钢薄板对冷轧产能的影响,特进行了大压下试验。通过对比分析得出大压下的伸长率、塑性应变比值比二轧程的略低,但二轧程的各向异性指数值也最大,容易引起冲压件的凸耳缺陷,并且增加冷轧次数和中间退火会使生产难度和成本大大增加。使用大压下工艺生产的零件各项质量指标均已满足深冲要求,可以考虑采用大压下工艺替代二轧程工艺。

1450mm六辊可逆冷轧机轧制超宽超薄料的试验

通过在国产1450mm六辊可逆冷轧机上将1.8mm×1250mm的SPHC热轧酸洗卷轧成0.18mm×1200mm超薄高精度带钢的单轧程轧制试验,不仅验证了国产1450mm六辊可逆冷轧机的可靠性和先进性,还证明了单轧程轧制超薄高精度带钢的可行性,由此可为企业降本增效提供技术参考。

优质中、高碳钢的冷轧长带生产

优质中、高碳钢的冷轧长带在生产过程中必须研究最合理的热处理工艺，以及最经济的热处理制度和轧程的安排，才能低耗高效地生产符合优质冷带技术标准的产品。

异型钢轧制关键技术研究与应用

从全轧程数值模拟、全流程工艺优化、全工序质量控制研究分析,三个维度有机协同融合,以降本增效和产量提升为出发点,通过升级轧辊材质、优化配辊模式和轧辊经济过钢量三个方面,来缓解当前的成本和效率的压力,在保证尺寸精度的同时,实现表面质量与生产效率双提升,助力产线发展,最终实现了异型钢轧制技术的高效集成。

Continuous extrusion and rolling forming velocity of copper strip

A new copper strip production technology combined with continuous extrusion and rolling technology was proposed. The roll velocity must first be matched with the continuous extrusion velocity to achieve continuous extrusion and roll forming. The bite condition of continuous extrusion was determined, and the compatibility equation between the roll velocity and parameters such as the extrusion wheel velocity, reduction, and strip size was established through mechanical by plastic theoretical calculations. The finite element model of continuous extrusion and rolling was then established by using the TLJ400 continuous extrusion machine with a roll diameter of 200 mm. The relationship between the continuous extrusion and rolling velocities was determined through numerical simulations by software DEFORM-3D, and the accuracy of compatibility equation of velocity was verified.

Densification process of 10%B_4C-AA2024 matrix composite strips by semi-solid powder rolling

Semi-solid powder rolling（SSPR） is a novel strip manufacturing process,which includes the features of semi-solid rolling and powder rolling.In this work,densification process and deformation mechanisms of B4 C and AA2024 mixed powders in the presence of liquid phase were investigated.The relationships between relative densities and rolling forces were analyzed as well.The results show that liquid fraction plays an important role in the densification process which can be divided into three stages.Rolling deformation is the main densification mechanism in deformation area when the liquid fraction is lower than 20%.When the liquid fraction is equal to or higher than 20%,the flowing and filling of liquid phase are the densification mechanisms in deformation area.The relative densities increase with increasing rolling forces.The relative density–rolling force curves are similar at 550 °C and 585 °C.The characteristics of the curve shapes are apparently different at 605 °C and 625 °C.

Continuous FEM simulation of multi-pass plate hot rolling suitable for plate shape analysis

In order to continuously simulate multi-pass plate rolling process,a 3-D elastic hollow-roll model was proposed and an auto mesh-refining module with data passing was developed and integrated with FE software,Marc.The hollow-roll model has equivalent stiffness of bending resistance and deformation to the real solid and much less meshes,so the computational time is greatly reduced.Based on these,the factors influencing plate profile,such as the roll-bending force,initial crown,thermal crown and heat transfer during rolling and inter-pass cooling can be taken into account in the simulation.The auto mesh-refining module with data passing can automatically refine and re-number elements and transfer the nodal and elemental results to the new meshes.Furthermore,the 3-D modeling routine is parametrically developed and can be run independently of Marc pre-processing program.A seven-pass industrial hot rolling process was continuously simulated to validate the accuracy of model.By comparison of the calculated results with the industrial measured data,the rolling force,temperature and plate profile are in good accordance with the measured ones.

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 modem 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.

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

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.

Multi-objective optimization of rolling schedule based on cost function for tandem cold mill

In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and rolling speeds for a specified product. The proposed schedule optimization model consists of several single cost fi.mctions, which take rolling force, motor power, inter-stand tension and stand reduction into consideration. The cost function, which can evaluate how far the rolling parameters are from the ideal values, was minimized using the Nelder-Mead simplex method. The proposed rolling schedule optimization method has been applied successfully to the 5-stand tandem cold mill in Tangsteel, and the results from a case study show that the proposed method is superior to those based on empirical formulae.

Roll shifting strategy with varying stroke and step in hot strip mill

A new roll shifting strategy with varying stroke and varying step was investigated,Two characteristic parameters including cat ear height and gap contour smoothness were introduced to assess the effect of shifting strategy on roll wear,and the relation between characteristic parameters and shifting strategy was established.Both varying stroke and varying step can reduce cat ear height and gap contour smoothness,so the shifting strategy with varying stroke and varying step is better than the one with either varying stroke or varying step,Based on the effect of shifting control parameters on characteristic parameters of roll wear,the selection principle of these shifting control parameters was gained.A case study was conducted to validate the proposed roll shifting strategy,reducing uncontrollable quartic loading gap contour,improving strip profile and extending rolling length of a rolling campaign.

Analysis and prediction of fishtail during V-H hot rolling process

The fishtail in head and tail of the slabs was studied during V-H hot rolling process. With the application of ANSYS/LS-DYNA, simulation analysis was used to research this process. The various factors which have a great influence on fishtail shapes were analysed, such as initial width, initial thickness, radius of the edger roll and horizontal roll, edging draught,horizontal reduction rate, and friction coefficient of the surface. Then the curves that can describe the shapes were obtained. After a certain time of self-learning, the optimized curves were given out. At last, through the fitting of the simulation test results, the math models for the area of fishtail defect changing with the presented factors were received. The experimental results show that the accuracy of the prediction for the fishtail shapes is more than 95%. With the application of the prediction for the fishtail shapes and the area of the fishtail defect, the loss rate of the slab is decreased by about 0.1%.

Bending analysis and control of rolled plate during snake hot rolling

In order to study the bending behavior of aluminum alloy 7050 thick plate during snake hot rolling, several coupled thermo-mechanical finite element(FE) models were established. Effects of different initial thicknesses, pass reductions, speed ratios and offset distances on the bending value of the plate were analyzed. ‘Quasi smooth plate' and optimum offset distance were defined and quasi smooth plate could be acquired by adjusting offset distance, and then bending control equation was fitted. The results show that bending value of the plate as well as the extent of the increase grows with the increase of pass reduction and decrease of initial thickness; the bending value firstly increases and then keeps steady with the ascending speed ratio; the bending value can be reduced by enlarging the offset distance. The optimum offset distance varies for different rolling parameters and it is augmented with the increase of pass reduction and speed ratio and the decrease of initial thickness. A proper offset distance for different rolling parameters can be calculated by the bending control equation and this equation can be a guidance to acquire a quasi smooth plate. The FEM results agree well with experimental results.