共查询到17条相似文献,搜索用时 46 毫秒
1.
梅钢1420轧制力模型在Hill方程基础上,分解提炼3个关键因子,建立了显函数的轧制力模型,并进行变形抗力参数和摩擦系数参数的自适应修正以提高轧制力模型精度.经生产实践数据检验,该模型自适应系数在0.9~1.1以内,满足模型在线控制要求. 相似文献
2.
为提高中厚板精轧机轧制力的预报精度,建立了Sims公式简化式与人工神经网络相结合的轧制力预报综合模型。以3 000 mm中厚板精轧机实测数据为基础,用Sims公式简化式计算轧制力主值,利用MAT-LAB人工神经网络工具箱,建立BP神经网络模型预报轧制力的偏差值,用提前结束的方法来训练网络。模型的综合采用加法和乘法两种方式。结果表明,与单独采用Sims公式简化式相比,综合模型的预报精度提高很多,而且加法网络算法的预报效果比乘法网络算法更好。 相似文献
3.
采用了BP神经网络对热轧无缝钢管穿孔过程中轧制力进行预测,在BP算法学习过程中引入了附加动量法和自适应学习速率,结合Levenberg-Marquardt优化方法,加快了学习时的收敛速度,试验证明,取得了良好的学习和测试效果。研究结果可为斜轧穿孔工具设计和工艺调整提供一定的理论依据,对解决生产中出现的实际问题、开发新产品和新工艺提供有效的指导。 相似文献
4.
对《机床夹具设计》^「1,2」中抽象的滑柱力学模型,进行了分析,指出其错误在于滑柱承受的是一个非平衡力系,建立了基于平衡力系的力学模型,并推演出了相应的力学计算公式。 相似文献
5.
针对气球力Snake模型存在对初始轮廓线位置敏感和弱边界泄露的缺点,将图像的全局信息融入到气球力Snake模型中,提出了基于模糊聚类的自适应气球力Snake模型,并应用于图像分割。该模型可以根据图像的区域信息自适应地改变气球力的方向和大小,使得轮廓线能正确收敛到目标边界。实验结果表明:改进模型放宽了对初始轮廓线位置的限制,克服了弱边界泄露的缺点,能使轮廓线在深度凹陷区域得到正确收敛,对噪声的鲁棒性强,且不存在GVF场的临界点问题。 相似文献
6.
对<机床夹具设计>[1,2]中抽象的滑柱力学模型,进行了分析,指出其错误在于滑柱承受的是一个非平衡力系,建立了基于平衡力系的力学模型,并推演出了相应的力学计算公式. 相似文献
7.
对《机床夹具设计》[1,2 ]中抽象的滑柱力学模型 ,进行了分析 ,指出其错误在于滑柱承受的是一个非平衡力系 ,建立了基于平衡力系的力学模型 ,并推演出了相应的力学计算公式 相似文献
8.
为了提高粒子滤波的性能,使用集合卡尔曼滤波对建议分布进行改进,同时提出了用于视频跟踪的自适应融合模型.使用集合卡尔曼滤波结合当前的观测信息构造建议分布,结合当前观测信息对每一个粒子进行集合分析,得到新的建议分布,依据新的建议分布对粒子进行采样,同时在跟踪过程中将颜色特征模型和形状特征模型进行融合,并进行自适应更新.实验结果证明:相对于传统粒子滤波和扩展卡尔曼粒子滤波,使用新的建议分布可以更有效地降低均方根误差,同时自适应融合模型的稳定性要高于使用单一颜色模型.使用新的建议分布和融合模型,可以有效提高粒子滤波的准确性和稳定性. 相似文献
9.
Fromthetimewhen3-rollmillsareinvelltedtotheendof1970's,theyhadbeenusedinhotrollingofwirerods,especiallyinproducingofnon-ferrousmetals.Itisestimatedthatapproximately90%ofthewirerodsmadefromaluminumandaluminumalloyswereproducedonthe3-rollmillsatthattim... 相似文献
10.
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. 相似文献
11.
陈树宗;张欣;彭良贵;张殿华;孙杰;刘印忠 《中南大学学报(英文版)》2014,21(5)
In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost function 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 functions, 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. 相似文献
12.
厚度精度是衡量带钢质量的重要指标.本文通过对首钢京唐酸轧机组厚度控制系统进行了深入研究,分析了包括1#机架FF-AGC、BISRA-AGC和GM-Smith AGC以及2#-5#机架MF-AGC的综合的厚度控制策略.实际应用效果表明,成品厚度偏差小于±1%,达到了较高的厚度控制精度. 相似文献
13.
曹建国;徐小照;张杰;宋木清;宫贵良;曾伟 《中南大学学报(英文版)》2011,18(5)
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. 相似文献
14.
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. 相似文献
15.
在设备能力范围内,分析了冷辗扩加工的综合辗压区,综合考虑了辗压时的力能参数与坯坯变形状态,建立了轴承座圈冷辗扩加工工艺参数分析的数学模型。通过实例说明,所建立的数学模型是合理的,对系统地、科学地制定冷辗扩工艺规程提供了科学依据。 相似文献
16.
为满足新一代高技术冷连轧机宽幅电工钢薄板等高端板材“Dead flat”矩形断面超平材超高板形质量要求,采用显式动力学有限元法建立六辊冷连轧机一体化仿真模型,利用现场工业轧制试验数据验证有限元模型的准确性,定量分析电工钢完整轧制过程中不同轧制因素对有载辊缝凸度的影响规律;基于6辊UCM冷轧机板形控制机理和课题组自主设计的EDW-N(Edge Drop Control Work Rolls for Non-shifting of the Work Rolls)工作辊非窜辊辊形建立六辊冷连轧机电工钢矩形断面控制的弯辊力数学模型;由有限元仿真与现场工业轧制试验结果确定了六辊冷连轧机电工钢矩形断面控制弯辊力数学模型的参数,并验证了其准确性;某大型1 420 mm六辊冷连轧机生产应用现场连续检测反馈数据表明:取得电工钢高精度出口凸度均值C15≤7μm的比例从38.58%提高到67.74%的显著生产实绩,充分发挥了六辊冷连轧机的高精度板形控制能力,可在很大调节范围内对板形质量进行调控,为解决无工作窜辊的6辊UCM冷连轧机宽幅电工钢薄板矩形断面控制瓶颈难题提供了解决方案和实现路径。 相似文献
17.
文章在分析函数常用的级数法和迭代法算法的基础上,提出一种基于归约、逼近、重建的函数改进算法,满足浮点运算要求。通过测试证明了优化算法精度的优越性。同时,对基础数学库实现方法的研究,能够更有效满足高性能计算的精度要求和性能要求。 相似文献