Industrial tests of ladle refractories based on rocky olivinite of the Kovdorskoe deposit

The physicotechnical properties of ladle refractories based on rocky olivinite of the Kovdorskoe deposits, prepared by the technology of the St. Petersburg Institute of Refractories, are considered. Industrial tests of the experimental refractories in the lining of steel-teeming ladles of the open-hearth shop at the Cherepovtskii integrated iron and steel works have demonstrated that the attained durability of olivinite-containing lining (40 heats) exceeds 3.5 – 4 times the durability of conventional fireclay lining commonly used at the works. Rocky olivinite is a novel magnesia-containing raw material which should find wide use in the manufacture of ladle refractories.Translated from Ogneupory, Vol. 35, No. 1, pp. 27 – 28, January, 1994.     

Development of a Technology for Manufacture of Periclase-Carbon Refractories

A technology for manufacture of periclase-carbon refractories for the lining of steel-teeming ladles of oxygen-blowing converter is developed.     

Refractories of a fused periclase-chromite material for the wall lining of 100-ton arc furnaces

Conclusions The durability of a wall lining in 100-ton arc furnaces of MKhVP type refractories based on fused periclase—chromite material is 20–30% higher than that of a lining constructed of periclase—spinel brick produced from sintered magnesite and chromite ore.The chemical inertness, high resistance to attack by corrosive media, and the low content of low-melting silicates in the MKhVP refractories ensure that the rate of zone formation in the bricks is slow and the durability of the lining high.Bricks of fused periclase—chromite can be recommended as refractories for the wall lining of the arc furnaces of the Oskolsk Metallurgical Combine now being constructed.These refractories should also be subjected to testing in the roof lining of arc furnaces.Translated from Ogneupory, No. 7, pp. 26–30, July, 1978.     

Use of unfired periclase-carbon refractories in parts of linings of 350-ton steel-teeming ladles

Workers of the Azovstal’Company have established the causes of the decrease in the endurance of slag-line areas of linings of 350-ton steel-teeming ladles. In 1995–1996 they conducted industrial tests and introduced a process for lining the slag areas of 350-ton teeming ladles with unfired periclase-carbon refractories. The mean service life of a lining of a 350-ton teeming ladle with a slag line made of periclase-carbon refractories amounts to 23 heats on the average without hot repairs of the slag line during the campaign. The wear of the periclase-carbon lining in the slag line is 3.6–4.3 mm per heat. The specific consumption of refractories and materials for a lining has been decreased by 0.6–0.8 kg per ton of converter steel. Such an operating capacity for the periclase-carbon refractories in slag lines is provided by the composition and structure of the refractories, which possess a high heat resistance and resist the effect of the molten metal and slag. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 2, pp. 37–39, February, 1998.     

Testing lining materials in aluminum subchloride

Conclusions Tests of materials showed that for the lining of the reaction region in practice we can only use refractories made from sintered alumina; the content of Al₂O₃ in the article should be not less than 98%, firing of the articles should be done at above 1650°.Specimens made from aluminum nitride (AlN) gave good results in terms of chemical and mechanical resistance in conditions of the subchloride process, but since this material is scarce, it is recommended for the manufacture only of the most critical parts of the lining.Articles made from silicon nitride (Si₃N₄) or from silicon carbide with a nitride bond (SiC+Si₃N₄) can be used for lining the decomposer-condenser since it possesses adequate chemical resistance, high thermal conductivity, and preserve its strength with sudden changes in temperature and enables us to manufacture articles of complex shape with accurate dimensions.     

The use of a combined lining in copper production converters

Conclusions Strengthening of the above-the-tuyere zone of converter linings with fused periclasechromite refractories in combination with chromite-periclase heat-resistant refractories provides more uniform wear over the whole surface of the lining.With the use of a combined lining the life of a converter lining is at least as long or longer than the life of a lining with the use of only PKhP fused periclase-chromite refractories.The use of scientifically based heat-up conditions and converter operation taking into consideration the specific plant conditions may significantly increase the effect from the use of highly resistant refractories.As the result of use of combined linings in copper melting converters a 35–49% increase in converter life has been obtained.Translated from Ogneupory, No. 5, pp. 46–49, May, 1986.     

Mechanism of refractory wear in the reaction shaft of furnaces for melting of raw material in the suspended state

Conclusions The mechanism of failure of chrome-magnesite refractories under conditions of autogenous melting of sulfide ore was studied.On the basis of an analysis of the thermal operation of the lining taking into consideration the closeness of domestic refractories in thermophysical properties to Radex CN refractories, lining of the reaction shaft with domestic refractories was recommended.Translated from Ogneupory, No. 5, pp. 49–52, May, 1986.     

Improved refractories for the lining of blast furnaces

Conclusions A comprehensive comparative analysis of the principal properties of the refractories used for the lining of blast furnaces showed that the ShKD-type kaolin refractories produced by the Zaporozhe Refractories Plant possess the highest property indices and can be recommended for use under the heavy-duty service conditions in the lining of blast furnaces.A unified Standard for chamotte refractories for the lining of blast furnaces has been prepared from the results of a comprehensive analysis of their properties and the statistical data of the manufacturing plants and research institutes to meet the requirements of metallurgical plants and design organizations.Translated from Ogneupory, No. 8, pp. 20–28, August, 1976.     

Silicon carbide refractories in the lining of the cooler drum

Conclusions Tests were carried out at the Magnezit Combine with silicon carbide refractories in the lining sections subjected to maximum wear in the 36-m-long drum for the cooling of fired magnesite powder. The durability of the experimental bricks was 3–4 times greater than that of chamotte bricks.It was established that silicon carbide scrap and spoilage material are suitable for the production of high-durability refractories for service in a lining subjected to severe abrasion.Translated from Ogneupory, No. 5, pp. 28–30, May, 1978.     

Production and performance of dense corundum refractories

Conclusions The production technology was developed and production was launched of dense superduty corundum refractories with mullite—corundum binder. The products proved to be highly durable in the lining of a channel type induction furnace at the Volga Automobile Plant.The refractories are used also for the masonry of the roof of the high-temperature glass furnaces used in the production of glass fiber and are suitable as lining material for in-vacuo steel refining installations and other high-temperature heat-using equipment.Deceased.Translated from Ogneupory, No. 7, pp. 17–18, July, 1978.     

Competitiveness of products: A key to success in an incipient market economy

The Borovichi Refractory Plant has organized the production of new advanced refractories, including graphite-containing articles for continuous casting of steel, a variety of mullite-corundum articles, mortars, and refractories for lining blast furnaces. The prospects for refractory production are considered. Properties of the new refractories and data on their use in the metallurgical industry are presented.Translated from Ogneupory i Tekhnicheskaya Keramika, No. 8, pp. 23–26, August, 1996.     

Sialon-containing silicon carbide refractories

Conclusions We worked out the technology of sialon-containing silicon carbide refractories for lining the shafts of blast furnaces. It was shown that addition of MgO in combination with the waste products of the oxides of the rare-earth elements improves the strength and the other properties of the products fired at 1550°C in nitrogen atmosphere.The sialon-containing silicon carbide refractories exhibit a high resistance to the action of slags and are recommended for lining the lower portion of the shaft and the bosh of blast furnaces.Translated from Ogneupory, No. 5, pp. 6–8, May, 1992.     

Improving Lining Resistance Using High-Magnesia Fluxes in the Converter Steelmaking Process

Tests carried out at the Severstal Joint-Stock Co. and Magnitogorskii Iron-and-Steel Works JSC showed that a lime-magnesia flux containing 30 – 35% MgO used in the converter steelmaking process produced a favorable effect on the refractory lining resistance. Compositions for high-magnesia granules (50 – 65% MgO) were developed, their properties characterized, and the rate of solution in the slag melt was determined. Using these granules in the converter process makes it possible to increase the service life of periclase-carbon refractories for converter linings.     

Wear mechanism of linings of high-temperature tunnel kilns in the region of burner embrasures

The refractories of the lining of burner embrasures of tunnel kilns are subjected to intense wear in the form of scourings, effects of wall and embrasure deformations, and spalls during service. The service life of the lining of burner embrasures can be increased by raising the quality of the refractories and improving the design of the burners and the operating regime.Translated from Ogneupory, No. 12, pp. 22 – 25, December, 1994.     

Promising technologies for refractories of the unmolded type for various heating units

Prmising technologies are presented for preparing unmolded refractories for lining heating units. Properties for unmolded refractories, and results of testing them in various enterprises are provided.Work of an engineering section is described that was created on the basis of the Bogdanovich OAO Ogneupory. Translated from Novye Ogneupory, No. 11, pp. 23–29, November 2008.     

Fabrication Of Periclase-Carbon Refractories With An Antioxidant And Their Testing In A Lining Of A 370-ton Converter

Periclase-carbon refractories based on electrofused periclase with an additive of passivated aluminum have been tested in service in the top cone of a 370-ton converter of the Magnitogorsk Metallurgical Works. The lining with experimental refractories withstood 1501 heats whereas the endurance of commercial periclase-carbon refractories of grades PUPK-6 and PUPK-8 equals 1185–1416 heats. It was concluded that the periclase-carbon articles with an aluminum antioxidant have good prospects for lining converters.     

Service of zirconia refractories in continuous furnaces for quartz glass melting

Data are given on the durability of baddeleyite refractories of grade TsTsPP, which contain no stabilizing additives, in operation in the lining of continuous furnaces for melting quartz glass at the Dzerzhinskii Glass Works. In operation in contact with molten quartz at a temperature of (2000 Mp 10)°C, the average (for a year) durability has increased up to 82.5 days compared with the lining made of refractory sectors of CaO-stabilized ZrO₂, which had a durability in these furnaces up to 25 days. It is noted that the durability of furnace linings made of baddeleyite refractories is limited by the durability of the roof plates. With the use of a water-cooled roof, the durability of the furnace lining was increased up to 267 days, but the heat losses were higher. The results of comparative tests of baddeleyite refractories with different porosity (between 9.6% and 22.3%) and of those based on natural baddeleyite of natural grain size and on electrofused ZrO₂ are given. No differences in their durability have been established. The results of examining the refractories after their operation in furnaces are also considered.Translated from Ogneupory, No. 2, pp. 25 – 28, February, 1994.     

Refractories for lining mobile mixers

Conclusions New and effective refractories have been developed whose physicotechnical and working parameters are better than those of existing Soviet and foreign materials. Commercial production of them has been organized.MKFU-83 and KKFU-76 refractories increase mixer lining resistance by substantial factors and reduce the number of repair cycles and the material and labor costs, while increasing the metal output. The refractories are recommended for use in steel-melting processes (electric furnaces and buckets).Translated from Ogneupory, No. 2, pp. 24–26, February, 1991.     

The effect of degassing technology parameters and the quality of periclase-chromite refractories on their wear resistance in vacuum chamber lining

The results of an integrated study of external factors on wear resistance of periclase-chromite refractories in vacuum chamber lining are discussed. It is established that the mineral composition and structure of magnesian-spinellide refractories are the least liable to transformations. __________ Translated from Novye Ogneupory, No. 9, pp. 35–38, September, 2006.     

The nature of the destruction and method of increasing the resistance of electric furnace linings

Conclusions During service, abundant saturation of the lining by components of the melting region is observed. The amount of silicates in the slag belt reaches 40–60% and in the high-lying lining — 10–15%.In regard to composition of the silicate bond in the working zones the lining is divided in height into two zones: the slag belt and the high-lying part. In the slag belt the bond is composed chiefly of cuspidine and fluorite; in the high-lying part — of dicalcium silicate and glass.Formation in the silicate bond of cuspidine and fluorite is due to the high rate of wear of the lining of the slag belt.In refractories of high density there is a smaller zone impregnated with reagents of the melting region, and so there is less wear during service.Further increase in the life of the lining can be obtained by using refractories with a minimum porosity in the slag belt and opposite the hot-phase arc; such refractories include fusion-cast blocks.