Testing ladle brick made by various factories

Conclusions The resistance of linings in steel-casting ladles depends on the working conditions and the construction of the lining, the quality of the brick laying during repairs of the working layer, and the resistance of the ladle brick. The greatest effect on the wear of the lining in ladles is exerted by the following working conditions: chemical composition of the slag, temperature of the metal being cast, the dwell time of metal and slag in the ladle during one casting, the height of the slag layer in the ladle, the thickness of the lining in each belt of the structure. The quality of the structure in the ladles is mainly determined by the size of the joints, the care with which they are filled with mortar, uniformity of drying and warming-up of the ladles before filling them with metal.The resistance of the ladle brick depends mainly on the apparent porosity and nature of the pores and the concentration of fluxes and mullite in the brick.The highest resistance in service was shown by Zaporozh'e ladle brick made from Polozhe kaolin and having the lowest apparent porosity. The concentration of iron oxides in the brick was moderate, and on average equalled 1.39%.In terms of falling resistance the ladle brick of the remaining concerns can be placed in the following order: Chasov-Yar, Semiluks, Bogdanovich, Magnitogorsk, and Borovich.In order to increase the resistance of steel casting ladle linings it is necessary to increase the resistance of the ladle brick by reducing the apparent porosity, using raw materials with low concentrations of fluxes and improving the firing in order to obtain the maximum conditions of the ladle, reducing to a minimum the quantity of slag and reducing the casting time; to use a more rational thickness for laying the ladles over the courses, taking into account better use of their capacity.Translated from Ogneupory, No.5, pp. 27–32, May, 1970.     

Making ladle products using North Onezhsk bauxites

Conclusions It was found that the North-Onezhsk bauxites are promising raw materials for the production of highly resistant ladle bricks.We developed and mastered a technology in the BKO conditions for making ladle brick using these bauxites containing up to 6% iron oxides.In the lining of the steel ladles made with the use of bauxite chamotte, the bricks wear out 30–40% less than with ordinary ladle brick produced by BKO and the Chasov Yarsk Combine.Translated from Ogneupory, No. 8, pp. 4–9, August, 1980.     

Ladle bricks from clays of the Kirovograd and Polozhsk regions

Conclusions Use of the experimental brick made by the Chasov-Yar Combine makes it possible to increase the life of the lining of 230-ton steel casting ladles at the Kirov factory by about 1.5 melts.In addition the irregular erosion of the test brick without the formation of funnel-like hollows permits rapid removal of scale from the ladle.Manufacture of ladle brick from the new batch does not require great changes in the technology nor extra equipment.     

加废钢条件下铁水包的异常侵蚀与用材问题探讨

对铁水包的异常侵蚀进行了调研,对铁水包用砖的性能、组成与结构进行分析.结果表明:1)铁水包包壁采用的铝碳化硅碳砖与包底用铝碳化硅碳砖不同,含较多的叶蜡石,Al2O3含量只有36.32％(w);体积密度、显气孔率、耐压强度均低于行业标准的要求;其抗氧化性差,使用过程中氧化形成多孔层,造成砖衬结构疏松,引起断砖、局部磨损及...     

Quartz-clay ramming compounds with quartz sand from the Latnensk deposits

Conclusions Ramming compounds based on Latnensk clay-containing quartz sand and intended for the monolithic lining of steelcasting ladles were developed and tested and are now in production.The average durability of the lining of the 180-ton steelcasting ladles of converter section No. 1 of the Novolipetsk Metallurgical Plant is 9–10 melts when it consists of a ramming compound produced from Latnensk quartz sand. The lining becomes unserviceable owing to the low durability of the working layer of the bottom. When using a ramming compound based on Chasov-Yar semifatty sand, the lining of the lateral parts of the ladle bottom and that of the slag zone are severely eroded after 7–8 melts.Deceased.Translated from Ogneupory, No. 1, pp. 14–17, January, 1978.     

Mechanized guniting of the lining of steelcasting ladles

Conclusions A method has been developed and equipment constructed for guniting steelcasting ladles without any manual labor. Experiments and tests were carried out with compositions based on quartzite, Chasov-Yar semiloamy sand, and fine-ground chamotte. The industrial-scale guniting tests showed that the durability of the lining of 130-ton steelcasting ladles increases by 30% (4.7 melts) on average with one guniting per ladle campaign.Translated from Ogneupory, No. 5, pp. 32–36, May, 1977.     

Performance of a ceramic frit anti-oxidation coating on a MgO-C refractory brick

In steel production, ladles must be preheated to minimize the heat loss of the steel melt, prevent thermal shock of refractory bricks (MgO-C), and to maximize the lining life of ladle. Partial oxidation of MgO-C bricks begins in the graphite bond during the preheating. Oxidation of graphite bond also causes a decrease in performance of the bricks because of an increase in the brick porosity. In this article, coating on a MgO-C brick surface by a ceramic film to protect against carbon oxidation was studied. Coated and un-coated bricks were heated at 1200 °C, cooled to room temperature, then the brick properties investigated. The oxidization resistance properties of brick with coating were much better than those without coating, which should lead to longer refractory service life.     

Life of stopper heads in continuous steel casting

Conclusions Chamotte heads with 5, 10 and 15% graphite differ from conventional chamotte by high thermal endurance, thermal conductivity and wear resistance. The increased rigidity of stopper heads with a graphite content of 5 to 15% used in combination with magnesite sleeves enhances the formation of longitudinal cracks.Chamotte specimens fired at 1230° C are endowed with high wear-resistance. They differ from conventional chamotte refractories by higher thermal endurance and provide for good stopper service in reladling killed steel.High-alumina SP-9-type heads made at Chasov-Yar Combine wear less in intermediate ladles and are endowed with greater thermal strength than chamotte heads.The higher quality of the chamotte heads under conditions of Stalino Metallurgical Plant in comparison to that of Krasnoye Sormovo Plant is not only due to the quality of the refractory but also to such factors as the rate and degree of preheating intermediate ladles before filling with metal, careful placement of the stoppers, and use of graphite packing around the teeming head.Despite higher wear SP-12-type chamotte heads made at Chasov-Yar Combine allowed normal teeming of rimmed steel in 50 ton ladles.To ensure a steady service of the stoppers in continuous steel casting the preheating of intermediate ladles of 1300 and the use of precooled stoppers are recommended.     

铝镁尖晶石炭砖在盛钢桶上的应用

以铝镁尖晶石炭砖取代铝镁不烧砖在首钢第三炼钢厂９０ｔ盛钢桶上应用时效果良好．其侵蚀速率低，工作面反应层与变质层很薄，有较好的抗热震性能，尤其对抵抗碱性熔渣的侵蚀和渗透明显优于铝镁不烧砖。试验结果表明铝镁尖晶石炭砖的使用寿命比原用铝镁不烧砖提高一倍以上。     

Indispensability and Vulnerability of Magnesia-carbon Bricks for Steelmaking Process

The manufacturing techniques of magnesia-carbon bricks in China have been documented from raw materials,production(process and facilities)to performance and wear issues in the ladle.Magnesia-carbon bricks made of ordinary fused magnesia is the prevailing material used in the slagline of the ladle,but its service life is substantially lower than the bricks based on large-periclase-crystal fused magnesia.In two types of fused magnesia,the average values of periclase crystal size are in double for their difference.It is suggested that large-periclase-crystal fused magnesia should be used for manufacturing magnesia-carbon bricks for the slagline of the ladle by abandoning ordinary fused magnesia,in order to have a prolonged service life,increase the availability of the ladle and reduce the number of downtimes of the ladle.Free phenol in resin produced in China should be as low as that of resin made in Europe,to improve production environment and reduce smoke emission during the ladle preheating.There are large spaces to promote the productivity of magnesia-carbon bricks in China,with high intensity mixers and hydraulic presses.Expansion controlled magnesia-carbon bricks in the ladle depend on the optimized combination of sintered magnesia,Carbores and antioxidants as the matrix,to minimize the premature wear of vertical cracks and joint opening formed in the ladle lining.     

Tests of olivinite-based ladle refractory brick

A lining of burned forsterite—chromite brick, with the olivinite mined at the Khabozerovskoe deposit as the base, was tested in the 385-ton steel-teerning ladle of the converter plant at the Severstal' Works. The brick was made by the method developed at the St. Petersburg Institute of Refractories. The characteristics of the brick are given. The ladle lining was tested on a wide range of converter steel grades. At the end of the service period, the lining was examined and the nature of its wear was identified. The experimental lining withstood 23 heats. It is thought promising to use refractory brick of the forsterite composition in large-tonnage steel-teeming ladles.     

Increasing the life of ladle brick

Conclusions A technology was developed for the manufacture of ladle brick of high resistance. The difference between the proposed method and that used at present is in the increase in alumina content of the bond part of the batch. The nonplastic may be ordinary grog made of first or second-grade clays normally used in the manufacture of ladle bricks. The optimum Al₂O₃ content in the bond part of the batch is 55–60%.A compulsory condition for increasing the service life of the ladle brick, in addition to a high content of alumina, is the density of the bonding part of the batch. Therefore, the firing temperature of the goods should be determined not by the porosity of the finished product in general, but by the porosity of the bond part of the batch.The chief norms for the manufacturing technology are as follows: a) a batch content of 50–55% ordinary grog made of first and second-grade clays, water absorption not more than 5%; b) a batch content of 50–45% mixture of combined grist of high-alumina grog and clay; the ratio of grog to clay in the mix should be from 6535 to 7030.The conclusions of the present article have been proved by manufacturing an industrial batch of goods and testing them in linings of ladles [14]. The technology has been included in a project for reconstructing the Bogdanovich refractories plant.     

Production technology for ladle brick using semiacid clays

Conclusions A technology was developed for making ladle brick from Ch1PK semiacid clays mined in the Chasov Yar area.The biggest difference between semiacid ladle brick and firebrick is the after-expansion at service temperatures of 1500–1600° C which reaches about 3% and which densifies the structure of the ladle.The life of semiacid brick in 250-ton steel ladles on average is 11% higher than ordinary ladle brick.The production of ladle brick from semiacid raw materials is economic. The lower cost of the product is a result of using cheaper raw materials and firing the clay into chamotte and products at lower temperatures.Translated from Ogneupory, No. 5, pp. 3–7, May 1967.     

Innovative Lining of Unburnt Al_2O_3-MgO Brick for 300t Steel Ladle in Baosteel

The manufacture of clean steel needs high performance carbon-free bricks for ladle lining.Based on long term application experiences of the prefab Al₂O₃-MgO blocks,unburnt Al₂O₃-MgO brick has been developed by pressing a mix of alumina,spinel and magnesia as major raw materials and Al₂O₃-MgO gel powder as binder.In addition to low open porosity and high strength,the unburnt Al₂O₃-MgO brick shows superior corrosion resistance and thermal shock resistance to the prefab block.Field trials in a 300t steel ladle have indicated the residual lining of unburnt Al₂O₃-MgO bricks showed smooth surface without large spalling and seldom steel infiltration,consequently longer service life than the prefab blocks.The reliable,unburnt Al₂O₃-MgO bricks have more advantages of high efficiency,energy-saving and eco-friendly production.It will be one of the best options for ladle lining in the manufacture of high-purity steel.     

Introduction of rammed linings for 250-ton steel-teeming ladles at Makeevka Metallurgical Combine

Conclusions In the open hearth shop of the Makeevka Metallurgical Combine the 250-ton steel-teeming ladles have been converted from a brick lining to a monolithic quartzite-clay rammed lining prepared with the use of a sand slinger using MKG-1 mixture according to Technical Specification 14-8-252-77 produced by the Krasnogorovka Refractory Plant. The use of monolithic linings of the ladle walls provided an increase in their average life from 9.06 to 15.6 heats.During service of the quartzite-clay rammed linings in teeming ladles partial degeneration of the quartz into cristobalite and full transformation of the fine crystalline binder into glassy occurs.The annual saving from the introduction of monolithic rammed linings of the 250-ton steel-teeming ladles of the Makeevka Metallurgical Combine was 2000,000 rubles.Translated from Ogneupory, No. 1, pp. 47–49, January, 1985.     

Ladle brick from semiacid clays

Conclusions The main feature of the technology developed for the production of high-density ladle brick which expands in service, made from semiacid clay from Chasov Yar and Druzhkov sources, is the regular firing cycle for the chamotte and the finished products, namely completion of firing in the temperature range in which we can guarantee sintering of the material, but in which bloating has not yet begun.The life of the ladle brick in service made from semiacid clays is greater than that of high-chamotte ladle brick owing to the high density of the structural joints, governing the expansion of the working layer of the brick coming into contact with metal and slag.Mass production of semiacid ladle brick using the technology developed by VIO should be organized in refractory plants of the UkrSSR.Deceased.Translated from Ogneupory, No.2, pp.14–17, February, 1967.     

Post-mortem analysis of MgO–Al2O3–C bricks containing bauxite used in steel ladle walls

A serious problem with integrated masonry linings ladle was that the ladle wall bricks were difficult to be partially replaced. Thus, the service life of the ladle was determined by the properties of ladle wall bricks. In this study, the new generation of MgO–Al₂O₃–C bricks with bauxite aggregates was tested in a ladle lining of an integrated steel ladle for 103 cycles, and the corroded microstructure of the used brick was investigated. A multilayered structure of bauxite aggregates could be observed in the used brick, which inhibited the slag penetration along the boundary of the magnesia aggregates and reduced the degree of the aggregates fall off from the used bricks. Besides, during the process of slag penetration, bauxite aggregates could melt into the slag, which increased the viscosity of the slag and weakened the penetration ability of the slag. The MgO–Al₂O₃–C bricks with bauxite addition could improve the service life of the ladle to a certain extent.     

Guniting the lining of 300-ton steelcasting ladles

Conclusions The practice of guniting the lining of steelcasting ladles has been introduced for the 300-ton ladles of the open-hearth division of the Cherepovetsk Metallurgical Plant. The guniting parameters are as follows: the temperature of the lining of the ladle wall should be 60–120°C; the amount of wetting agent (sodium silicate solution) for the optimal adhesion of the G unite layer to the brick masonry should give the G unite mix a moisture content of 8–15%, and the density of the aqueous sodium silicate solution should be 1.15–1.30 g/cm³.The guniting operation is carried out with a remote-controlled centrifugal-action machine which permits the operation to be carried out at a temperature in the ladle of 200°C. The durability of the ladle lining increases significantly when the lining is gunited regularly up to five times per campaign. The estimated economic benefit from the practice of guniting the 300-ton steelcasting ladles is 85,000 rubles/yr.Deceased.Translated from Ogneupory, No. 2, pp. 29–32, February, 1978.     

A Retrospective Review of Alumina-magnesia-carbon Refractories

The residual expansion of in-situ spinel formation in using of alumina-magnesia-carbon(AMC)bricks monolizes the lining of steel-making ladles with the closure of their joints,which has been an effective solution avoiding washing out of the joints in ladle lining by the reduction of the penetration of liquid slag and molten steel.Alumina-magnesiacarbon refractories are overall reviewed,in terms of major raw materials,thermal evolution,corrosion and oxidation,and thermomechanical behavior,as well as type,addition and fraction of magnesia used.General commercial products contain 5%-10%MgO and 5%-10%C with a certain amount of metallic aluminum powder,which is believed to facilitate spinel formation at early stage of heating-up,although high magnesia containing AMC bricks are studied and used sometimes.With low ratio of Al₂O₃/C=12.9 and the carbon content of 6.4%C,AMC brick exhibits the highest corrosion resistance.It is important to determine the type,addition and fraction of magnesia used in AMC refractories for demonstrating high corrosion resistance and superior thermomechanical behavior.     

再生镁碳砖和铝镁碳砖在精炼钢包上的应用

介绍了采用64%～88%质量分数的用后钢包再生料制造的再生镁碳砖和再生铝镁碳砖的性能以及在精炼钢包上的应用情况。使用结果表明,根据使用条件和再生料的特点,把镁碳砖的制造技术和使用条件结合起来设计制造的再生镁碳砖,其使用效果显著好于原镁碳砖:在300 t精炼钢包渣线上的使用寿命提高15%,在50 t LF-VD炉渣线上的使用寿命提高50%以上。