基于GRNN神经网络的4200轧机宽展模型

 轧制过程中,针对4200轧机在轧件宽展变化自动预测和控制,分析了轧制过程中宽展变化的影响因素。在神经网络技术和现场实测数据的基础上,利用Matlab人工神经网络工具箱,应用GRNN广义回归神经网络建立宽展变化预测模型来提高轧制宽展变化预测的精度。结果表明,该方法建立的模型可以实现对宽展变化的预测,其预测精度有较大提高。     

宽厚板轧制过程中的宽展浅析

论述宽厚板轧制过程中影响宽展的主要因素及宽展与轧件宽度之间的关系,从现场收集的板宽变化数据,总结出变形区长度与钢板宽度之间的变化规律。提出了宽厚板轧制过程中钢板宽度的控制方法。     

提高中厚板宽度设定精度方法的研究

分析中厚板轧制过程的工艺特点,指出不同轧制阶段的宽展对宽度设定精度都有影响.基于经典宽展公式,得到多道次轧制下的宽展系数计算模型,在该模型基础上给出纵横纵和横纵轧制策略下宽展阶段目标厚度的计算方法,并提出相应的自学习算法;指出采用纵横纵轧制策略,可以消除坯料公差对宽度设定精度造成的影响;而合理使用测宽仪和人工卡量数据,有利于提高宽度设定精度.     

1780mm热连轧粗轧宽展模型参数优化研究

1780mm热连轧生产线的粗轧宽展模型分析与其实际应用效果存在较大误差。为提高宽度控制预报精度，采用了优化宽展模型参数法来提高模型精度；运用麦夸尔特法（Levenberg-Marguardt）和优化程序回归出模型的参数。用优化后的参数替换原有模型参数来控制宽度。经检验，宽度预测精度与优化前相比有显著提高。     

热连轧粗轧区FES宽展模型及其优化

为了满足某厂1580热连轧机宽度控制精度需求,提高宽展模型的广泛适用性,利用ANSYS/LS-DYNA有限元软件,对热轧粗轧区立轧--平轧过程进行了模拟.根据模拟数据,系统地分析了轧件宽度、厚度、轧辊直径、立辊侧压量和厚度压下量对"狗骨"宽展、自然宽展和绝对宽展的影响规律.利用模拟数据并结合现场数据构造了FES(finite element simulation)"狗骨"宽展模型和自然宽展模型,并建立了PSO-BP神经网络(粒子群BP神经网络).最后,FES宽展模型与PSO--BP神经网络相结合预报第1、3和5道次的宽展,其预报值与实测值误差在1mm以内的均达到了99%以上,达到了宽度控制的精度要求.     

热轧粗轧宽度控制优化与改进

宝钢不锈钢公司1780mm热轧生产线上的宽度控制主要采用了粗轧设定数学模型(RSU)及自动宽度控制模型(AWC)。针对生产过程中出现宽度控制模型的设定计算值和实侧值时常有较大的误差、学习系数经常处于不稳定的波动状态等问题,深入分析了粗轧设定宽展模型,对宽展模型中水平宽展系数及立辊宽展系数进行了优化,并改进了宽度自学习方式。结果表明,1780mm热轧生产线带钢的宽度精度显著提高,由改进前的92%提高到目前的98%以上。     

基于深度学习的带钢精轧过程自由宽展预测

为提高带钢精轧过程宽度的控制精度,以实际生产数据为驱动,建立深度学习网络模型,对自由宽展进行预测。采用拉伊达准则对实际生产数据进行清洗,对清洗后的数据进行相关性分析,并提取相关系数大于给定阈值的特征。基于预处理后的特征数据,对深度学习网络进行训练,建立自由宽展预测模型。针对测试实例,分别采用该模型与传统数学模型进行预测,并从均方误差、最大偏差以及误差分布等多个方面进行对比分析。结果表明,所建立的深度学习预测模型,具有更高的预测精度和更好的性能指标。     

热轧宽度模型改造

为了改善国内某热轧厂宽度控制稳定性和精度,在对原有模型和质量问题分析基础上,针对粗轧宽度模型实施了模型架构、模型算法、模型参数、自学习方式、短行程控制以及宽展预测模型的改造和优化。对钢种层别进行细分,自适应参数考虑了不同轧制生产模式的影响,带钢的头尾短行程控制曲线采用了可变多点方式,增加了立辊孔型模型以及立辊磨损模型,在宽展计算时考虑孔型的影响磨损量的贡献,提高了宽度模型预报精度。实际应用结果表明,经过优化改良的宽度模型有效提高了宽度控制稳定性和产品精度。     

基于轧制机理和混合神经网络的热轧精轧带宽预测

热轧带钢成品的宽度精度直接影响产品成材率，是产品性能提升的关键，而精轧区带钢出口宽度的精准预测可以为粗轧区宽度控制模型参数提供及时的优化调整指导。传统机理模型与实际情况往往存在较大差异，现有的数据驱动模型大多采用神经网络方法，但没有考虑轧制数据的时序性以及数据剪枝带来的信息损失。为了进一步提升精轧带钢宽度预测精度，提出一种基于轧制机理的混合神经网络宽度预测模型，利用精轧宽展的机理模型计算宽度基准值，结合卷积神经网络(CNN)和门控循环单元(GRU)输出宽度预测纠偏值。利用2 250 mm热连轧钢厂数据集试验，结果表明本文提出的热连轧带钢宽度预测模型训练效率较高，98.7%带钢宽度的预测精度在4 mm内，较传统BP神经网络模型和其他单一结构网络有大幅提升，且模型在线测试速度满足工业现场应用需求。     

连铸坯倒角对粗轧宽展的影响及宽度模型改进

带倒角的结晶器能够改善连铸板坯角部在矫直段的高温延展性,显著减少角横裂的发生。然而,连铸坯的倒角对粗轧过程宽展量有很大影响。通过建立粗轧过程板坯形变的有限元仿真模型,系统研究了轧制过程中板坯倒角尺寸和形状对轧件宽展量的影响。结果表明,连铸坯倒角边长越大,相同的立辊侧压量下所产生的狗骨回展量越小,同时在水平轧制时所产生的自然宽展也越小,而倒角角度的变化对粗轧宽展的影响不显著。针对现有的宽展公式没有考虑轧件存在倒角的问题,给出了一个含有倒角参数的修正项公式。通过与现场实测数据和原宽度模型计算结果对比,对于带倒角的连铸坯轧制情况,修正后的宽展模型预报精度显著提高。     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.