The 30Cr2Ni4MoV steel was produced base on the 45 t EBT-LF-VD-VD Process.The results show that technologies such as classified management steel scrap,selected quality scrap steel,strengthen the dephosphorization in furnace,using slag to desulfurize in LF refining furnace,the second VD process for further remove [O],[H] and [N] are applied.The content of impurity elements meets the quality requirement of 30Cr2Ni4MoV lower-pressure rotor steel.Low content of oxygen can be achieved in low-silicon and low-aluminum conditions.

The main source,quantity,size distribution,composition and type evolution rule of non-metallic inclusions in SPHC steel were analyzed and studied through the castig sampling of Tangsteel FTSSR cold rolling base material (SPHC) steel,and the inclusions was scanned and detected automatically by ASPEX.The results showed that the inclusions were mainly Al2O3 after feeding aluminum line,and MgO-Al2O3 type inclusions were formed in molten steel during the refining process.The inclusions whose length larger than 5 μm were about 15％ after feeding aluminum line and inclusions floatation.Mter calcium treatment,the Al2O3 and MgO-Al2O3 inclusions had better deformation effect,and the inclusions were changed into CaOCaS-Al2O3 compound inclusions,the inclusions less than 5 μm were more than 95％.Based on these findings,The countermeasure such as optimizing slag-making and argon blowing system,optimizing production organization mode and raising the level of protection casting had been utilized,and achieved the purpose of reducing the inclusion content,shortening refining cycle,reducing the production cost.

以唐钢薄板坯连铸中间包为原型,设计了几种不同位置安装气幕挡墙的中间包方案.研究了不同方案的中间包流场和夹杂物的运动轨迹,表明气幕挡墙位置及流量可以改变中间包流场及夹杂物的运行轨迹.通过“刺激—响应”方法获得了“RTD曲线”,计算得到平均停留时间、死区、活塞区和混返区等参数.气幕挡墙的位置和吹气量等对其冶金效果会产生显著的影响,认为合理设计气幕挡墙可以改善中间包内钢水的流场,延长钢水停留时间,利于夹杂物的上浮.

In this article,based on analysis on properties of blast furnace dusts in Tangshan,a process for comprehensive recycling of blast furnace dusts is put forward and validated through a range of tests.The results show that in the process,blast furnace dusts including Fe and C can be effectively recycled,and non-ferrous metals such as K,Na,Pb,and Zn can also be separated and collected through multistage hydrometallurgical process,which realizes the comprehensive utilization of blast furnace dusts. The researches prove that it is the best way to utilize blast furnace dusts.

根据高炉灰特性,进行了高炉灰含碳球团添加黏结剂的试验研究.研究结果表明,不同种类黏结剂对高炉灰含碳球团的粘结机理不同,导致对高炉灰含碳球团生球、干球以及成品球的粘结效果不同.根据高炉灰含碳球团黏结剂的使用效果,应优先考虑使用复合黏结剂,其次考虑使用无机黏结剂水玻璃.研究结果为高炉灰高效使用提供了技术依据.

对唐钢ORD一S矿粉进行流态化还原过程实验，研究添加剂对矿粉粘结的影响。发现高温富氢条件下，铁矿粉中加人白云石60m i n后金属率达到71.07%，粘结指数只有16.26%，防止粘结的效果最好，最优的白云石量是铁矿粉的2%。白云石的催化-细化效应延长了还原时间，提高了金属化率，降低了粘结指数。

The φ25 mm Nb-Cr micro-alloyed Ⅲ level bar was produced by controlled cooling industrial trial process,The production process,chemical composition,mechanical properties and microstructure of the testing ribbed bar were analyzed.The results show that the microstructure of the tested ribbed bar is tempered S-(F + P) from surface to core.The ferrite grain size in the core is 9.0～9.5 level and more pearlite is formed.The tensile strength,yield strength and elongation after fracture is 65 MPa,70 MPa and 6.5% higher than those of the standard requirement,respectively.The chemical composition is optimized,the Mn,Cr,Nb content is decreased.The mechanical properties of the tested ribbed bar qualify the requirement of Ⅲ level ribbed bar,and the production cost is decreased.

Operation regulations of primary argon tower and refining argon tower were presented and causes of fluctuation in the refining argon tower were analyzed.It found out that main causes of the fluctuation were effect of degree of supercooling of liquid nitrogen.The operation was stable after regulation.

Analyzing the reasons of the pure argon column undulation.The measures are taken to return to normal production.

This article introduces the process design which transforms 6000m~3/h oxygenerator into 17 000m~3/h oxygenation project in oxygen making plant.It also recounts several considerations of selecting the air separation unit of oxygenerator.Considering design principles,it expounds the arrangement of air separation plant as well as the piping of Molecular sieve(MS) purification system and its alterations of partial process line.

薄板坯连铸中间包包盖(以下简称中包盖)在使用中受冷热交替作用和温度波动影响,使用条件苛刻.因此,中包盖用浇注料应具有良好的抗热震性能和较高的高温抗折强度以满足生产需要.但在实际使用中,耐火材料经常会出现分层剥落现象,从而降低了中包盖的使用寿命.浇钢或烘包时,剥落的浇注料更易造成浸入式水口的堵塞.本文将对中包盖用浇注料在使用时的剥落现象进行分析,并提出改进措施.