Characterization and activation of Basic Oxygen Furnace slag

BOF slags are by-products of steel conversion. They are a valuable mineral resource for the construction but have chemical properties that directly control their stability or any hydraulic activity. This paper provides a complete characterization and quantification of BOF slag phases in order to better understand their potential hydraulic activity. The acceleration of the hydration by chemical admixtures is also presented. The BOF slag variability is investigated on several samples with different origins and ages.BOF slag with different origins mainly contain 38-52% C₂S, 20-30% C₂F, 1-7% Ca(OH)₂, 11-13% Fe_1−xO, 2-8% CaO. Calcium silicate is present in β-C₂S form which is the active polymorph present in clinker. BOF slags have poor hydraulic activity at early ages which can be enhanced by calcium chloride addition.     

转炉氧枪防落制动装置的设计

介绍氧枪防落制动装置的结构和原理及受力分布计算。     

转炉炉壳变形及其控制

大型转炉用镁碳砖炉衬后，炉壳温度可达４７０℃或更高，造成炉壳蠕变而变形。研究了转炉炉壳变形的状态及规律，分析了炉体机械应力、温度应力及膨胀应力。并通过蠕变实验预测炉壳的残余寿命。还介绍了改善及控制炉壳变形的整形技术和冷却技术。     

西门子6SE70变频器在钢厂转炉倾动、氧枪升降控制电机上的应用

本文讲述了西门子6SE70变频器在转炉倾动、氧枪升降环节的控制原理及设计，以及在使用调试过程中所出现的问题及解决方案。     

Interfacial transition zone of cement composites with steel furnace slag aggregates

As previous studies of mortar and concrete with steel furnace slag (SFS) aggregates have shown increases or decreases in the bulk mechanical properties, this study investigated the microstructural cause of these opposing trends through characterization of the interfacial transition zone (ITZ) with quantitative image analysis of backscatter electron micrographs. Three SFS types – basic oxygen furnace (BOF), electric arc furnace (EAF), EAF/ladle metallurgy furnace (EAF/LMF) – were examined as aggregates in a portland cement mortar. The ITZ size for all SFS mortar mixtures was similar, with the ITZ of BOF and EAF/LMF being slightly more porous than mortar mixtures with EAF or dolomite. Microstructural examinations of the SFS particle revealed that BOF and EAF/LMF aggregates have different outer and interior compositions, with the outer composition consisting of a porous layer, which likely contributes to the reduced strength relative to EAF. The imaging results demonstrated that the type of SFS and its spatial composition greatly influences the bulk properties of mortar and concrete, mainly as a function of porosity content in the ITZ and the outer layer and interior porosity of the SFS aggregate.     

基于支持向量机碱度偏差估计的石灰加入量模型

提出碱度偏差估计模型,进而提出一种转炉炼钢石灰加入量计算方法.首先,使用支持向量机建立碱度偏差估计模型,预报输入碱度与炉渣碱度之间的偏差;然后,利用碱度偏差估计模型预报的偏差值修正传统公式中的碱度参数,再消除白云石加入量对石灰加入量的影响,得到改进的石灰加入量模型.应用该方法对一座150t转炉的实际生产数据进行计算,结果显示对碱度偏差的预报有着较高的精度,由此计算的石灰加入量可以满足实际生产的要求.     

炼钢潮污泥在铁矿造块中的配用技术

为解决炼钢污泥在烧结球团生产中配加难度大的问题，研究开发了一种新的配加工艺。该技术可将脱水后的炼钢潮污泥的含水率调整到40％左右，用专门设计的布料器薄薄地加在烧结或球团配料胶带的料面上，从而使混合料内的炼钢潮污泥呈高度分散分布。     

基于神经网络的转炉炼钢终点控制

转炉炼钢是一种非常重要的炼钢方法,终点控制是转炉炼钢后期的重要操作.由于冶炼过程温度极高,很难进行准确及时地测量,无法形成通常意义下的反馈控制.采用RBF神经网络预报转炉炼钢终点温度和碳含量,在此基础上提出了基于神经网络的动态终点控制方法来确定在补吹阶段需要的吹氧量和加入的冷却剂量,克服了传统控制方法中基于热平衡和氧平衡控制模型不准确的缺点,提高了终点命中率.     

轴承钢产品质量与生产工艺研究

本文系统地总结了国内外轴承钢质量与生产工艺技术，分析比较了各种轴承钢生产工艺方法。采用超纯净钢生产工艺和改善凝固偏析，是控制轴承钢质量的技术核心，而采用转炉工艺和连铸技术，可以明显地降低轴承钢生产成本，应在国内大力推广。     

Thermodynamics Behavior of Titanium for BOF Smelting Bearing Steel

Titaniumnitride is a kind of hard and crispyin-clusion, whichis harmful to the fatigue life of steelandis related to the titaniumand nitrogen contentsof steel ,that is ,the amount of titanium nitride in-clusion increases with the increase of titanium andnitrogen contents of steel[1 -3]. The nitride is moreharmful than oxides with the same di mension.It isnoted from experi ment results of the fatigue life ofbearing steel that when the titaniumcontent decrea-ses from40×10-6to 10×10-6,the fatig…