Tests on dinas concrete blocks in soaking pits of a blooming mill

Conclusions Dinas brick in the lining of soakingpits at 1400 – 1450 showed the same resistance as dinas brick, to the separating wall under the refractory layer the dinas concrete did not fuse and after 8 months of service was still suitable for further use.Temperature measurements show that the surface of the brickwork below the refractory lining heats up to 1200. This excludes the possibility of using heat-resistant concrete with a portland cement base and a chamotte filler in the brickwork of the basic walls of pits.Dinas concrete blocks can be used to replace dinas brick in the working lining of soaking pits and chamotte in the     

Experience in the service of and measures for improving the service life of coke ovens of refractory concretes

Conclusions Experience in the operation of coke ovens of Batteries Nos. 1 and 4 of Stakhanov Coke and Chemical Plant made of large dinas-quartzite blocks has made it impossible to confirm their technical advantages over ovens of normal small-piece refractories.Several years of observations of the surface condition of the concrete lining of coke ovens has shown that in general its resistance is at least as good as the resistance of the chamotte lining. The processes of graphitization of the coke battery concrete lining occur satisfactorily during service.To prolong the service life of refractory concrete batteries it is desirable to eliminate lining defects occurring in the initial period of service of batteries of blocks without delay.The recommended compositions of guniting compounds are quite effective for repair of the serface of dinas-quartzite concretes and possess good adhesion and life in the coking medium.Questions related to broadening of the introduction of concretes into the construction and repair of large-scale coke batteries are very pressing and require the continuation of investigations.Translated from Ogneupory, No. 3, pp. 47–50, March, 1987.     

Experience with the use of highly refractory concrete in slit heat-treatment furnaces

Conclusions A highly refractory concrete based on Portland cement containing chromite aggregate proved to have a high resistance in heat-treatment furnaces.This type of concrete can be used in furnaces for ferrous metallurgy and the machine-building industry, mainly where chromemagnesite brick is at present in use.Wider use, in the building of heating equipment, of large blocks of highly refractory concrete should help to mechanize installation work, reduce costs and sharply reduce building time, and also prolong the furnace life.     

Experience with the use of refractory concretes in structural components of open hearth furnaces

Conclusions Production tests showed that the wear of the blocks made of refractory concretes based on periclase cement and on Portland cernent in the walls of vertical channels, in the back wall and in the front columns of open-hearth furnaces does not exceed the wear of structures of refractory brick.It would be advantageous to continue tests on blocks of refractory concretes in open-hearth furnaces by extending the scale of the trials. The sizes of the blocks should be increased and their weight brought to three tons.For the large-scale use of large blocks of refractory concrete in open-hearth furnaces it is necessary to organize the plant manufacture of all components and to mechanize repair operations.A classification of refractory concretes was given in Ogneupory No. 5 for 1960 and in SNiP part I, section B, chapter 3, p. 11, Gosstroiizdat, 1963 [in Russian].     

An analysis of the reasons for the increased wear of the walls of the soaking pits of the 1150 slabbing mill of Il'ich plant

Conclusions It has been established that the increased wear of the silica refractory parts (concrete blocks and brick) in the soaking pit walls of the 1150 slabbing mill is caused by chemical interaction of the iron-manganese slag containing the aggressive intermetallic phase Fe_xAl_y with the silica lining with the formation of low-viscosity molten material.The type of steel has a significant influence on the wear of the lining. The most aggressive are killed and semikilled steels, which in contrast to rimmed steels are deoxidized with aluminum.The structure of refractories has a definite influence. The more dense dinas parts, which possess a strong tridymite bond of the crystals in the finely dispersed portion, are more wear resistant than the silica concrete blocks not containing tridymite.Testing of refractory concrete parts of magnesia spinellide or forsterite compositions in the walls (or only in the support zone) of soaking pits with liquid slag removal is recommended.Translated from Ogneupory, No. 3, pp. 42–46, March, 1986.     

Service of fireclay blocks with clay — Phosphate bonds in blooming soaking pits

Conclusions A technology was developed for making chamotted concrete blocks with clay-phosphate bond. A cycle was selected for thermal processing.Blocks were tested in the walls of the working cells of soaking pits used for blooming. The resistance of the block lining is 50% higher than that of the brick lining.The blocks wear out mainly because of slag formation at the surface and the edges, and also because of mechanical failure. Scaling was noted during service of the blocks after natural drying.The phosphate bond during prolonged heating contributes to the decomposition of the mullite, and has a mineralizing effect on the polymorphic inversions taking place in the silica.Chamotte concretes with clay-phosphate bonds can be recommended for use in heat-treatment furnaces.Translated from Ogneupory, No. 2, pp.21–26, 1971.     

Separation of the refractory powder in the flame-guniting of converters

Conclusions An analysis of the deposition of the refractory particles on the converter lining in cyclonic-flame guniting revealed the presence of a conspicuous maximum deposition which coincided with the site of the peak depositions in a hot converter model and in a real 130-ton converter.Erosion of the converter lining is uneven and the local burns can be effectively repaired by depositing a maximum of gunite in the zone where the residual thickness of the lining is at minimum.Translated from Ogneupory, No. 5, pp. 49–52, May, 1975.     

Corundum-silicon carbide-bearing concrete parts made using a liquid glass binder

Conclusions Using the method of simplex-grid experimental planning and the generalized function of desirability, we determined the range of optimum composition of liquid glass bonded corundum-silicon carbide-bearing concretes possessing the specified properties.The improved service characteristics of the corundum-silicon carbide-containing concrete products owe to their phase composition: the content of nonoxidized silicon carbide, the formation of secondary mullite from the products of oxidation of silicon carbide and the fine fractions of corundum, and due to the presence of virtually unaltered coarse corundum grains that are introduced by the corundum waste products of the Yurginsk abrasives factory.Evaluation tests are being carried out on the experimental corundum-silicon carbide-bearing concrete products that were placed in the lining of a soaking pit of the Krivorozhstal' steel plant and a recuperator of the Petrovsk factory.Translated from Ogneupory, No. 1, pp. 4–10, January, 1988.     

Magnesia blocks formed on a 3000-ton hydraulic press

Conclusions A production line containing a 3000-ton hydraulic press is used for manufacturing unfired chrome magnesite and forsterite concrete blocks for repairing the lining of heat-consuming plant by mechanical means.An analysis was carried out of the variation of the properties and chemical composition through the block and with the heat treatment temperature, and of the deformation and thermophysical properties and slag resistance of the blocks. The blocks can be recommended as lining material for the walls of the slag pockets and vertical channels of open-hearth furnaces of varied capacity, and for the floor and lower part of the walls of soaking pits.With these blocks the process of lining metallurgical equipment can be mechanized, labor productivity is higher, and the useful life of the individual lining elements longer. The savings achieved from using the blocks as lining material amount to 13–15 rubles/ton blocks.Translated from Ogneupory, No. 6, pp. 4–9, June, 1976.     

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.     

New refractory concretes and binding systems: Basic trends of development, production, and use of refractories in the XXIst century. Part I. Trends of development, binding systems

General trends in the development, production, and service of refractories are considered. The share of refractories used in ferrous metallurgy amounts to 60–70%, which means that the predominant trend is determined by the requirements imposed on the refractories used in the steel industry. The proportion of unshaped refractories in the total production will inevitably grow. The basic problem in this field is the improvement of their matrix (disperse) phase, i.e., the binding system. The main types of refractory binders, of which highly concentrated ceramic binding suspensions (HCBS) are the most interesting, are considered. In contrast to natural ceramic binders (clays) HCBS are artificial systems that can be obtained on the basis of many refractory materials. The priority aspect in the creation of new refractory concretes (castables) and binders is described. The first artificial ceramic binders and cement-free refractory concretes based on them were created and installed by the author at the end of the 60s, and in the 70s he suggested many types of ceramic castables, including superlow-cement ones. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 2, pp. 4–13, February, 1998.     

Production and service testing of magnesite-chrome concrete

Conclusions In addition to magnesite-chrome concretes with periclase cement base, they can also be manufactured using a periclase-spinel cement. These concretes show less initial strength, but they soften to a lesser degree over the range 400 to 1000–1200°, hence after heating their strength is not lower than concrete with a periclase-cement base.The least softening of magnesite-chrome concretes over the given temperature range is shown by those with the addition of magnesium sulphate solution and soluble glass; as the modulus of the soluble glass is reduced, the compressive strength of the concretes under air-dry conditions and during heating increases. To obtain strong concretes, the soluble glass modulus must come within 1,8–2,2.In pneumatic tamping the strength of magnesite-chrome concretes is much greater than in vibration methods.In the spouts of electric steel-smelting and open-hearth furnaces, magnesite-chrome concrete showed a high degree of resistance, and its use for this purpose should be widely recommended.In the walls of an electric steel smelting furnace, the magnesite-chrome concrete was not inferior in strength to magnesite brick. The concrete containing magnesium sulphate was particularly satisfactory in this respect.The positive results of the test show the advisability of using concretes with a magnesium sulphate bond in the walls of electric furnaces with a view to replacing rammed linings made with a tar and pitch bond.The use of concrete for lining arresters in vacuum steel casting ensures satisfactory steel casting and has no effect on the quality of the metal.     

Periclase — Chromite concrete for lining of cement kilns

The object of the study is the technology of refractory concrete on a composite sodium-silicate binder for the lining of the sintering zone of rotary cement kilns. The developed composition of the refractory concrete contains chromium ore as the filler, which makes it possible to improve the operating properties of the material. The processes of formation of high-refractory compounds and the formation of a buffer zone at the clinker — refractory boundary in the concrete operating in the sintering zone of clinker kilns have been investigated. The physico-technical properties of the refractory concrete and the results of its experimental industrial testing are also given.Translated from Ogneupory, No. 3, pp. 23–24, March, 1994.     

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.     

Refractory concrete parts for edging the walls of soaking pits

Conclusions The technicoeconomic desirability of replacing chamotte brick in the edge of soaking pits with concrete parts of bauxite or of a mixture of commercial grade chamotte and silicon carbide part scrap using high-alumina cement was shown. The life of the upper structure of the soaking pit doubled, the time for repair of this element of the lining was reduced by more than 10 times, and the heavy bricklaying work was replaced by less laborious assembly work.Translated from Ogneupory, No. 8, pp. 30–32, August, 1982.     

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.     

Testing the bond of refractory concretes in zinc scrap melts

Conclusions Compositions of bonding or refractory concretes with high contents of chrome spinel are stable inregard to molten clinker produced in the reprocessing of zinc-containing scrap.The bonds of refractory concretes made from slags obtained in aluminothermal production are resistant to molten clinker.It is desirable to use slags obtained from melting metallic chromium, and to a less degree titanoaluminous slag as finely milled constituents of the bond in refractory concretes for lining rotary furnaces that are used in zinc production.The final conclusions will be made after we have investigated refractory concretes containing bonds that are more resistant in molten clinker.Translated from Ogneupory, No. 1, pp. 26–31, January, 1968.     

Drying and firstheat up of a kiln unit with cyclone heat exchangers with a lining of refractory concretes

Conclusions An accelerated drying and first heat up cycle was developed for a kiln unit for dry production of clinker with a capacity of 3000 tons/day with cyclone heat exchangers with a lining of refractory concretes of high-alumina cement with a chamotte aggregate. The drying of the lining and the heating of the unit were done in 4 days. The results of the work indicate the desirability of use of refractory concretes for lining the cyclone heat exchangers of kiln units for dry production of clinker.Translated from Ogneupory, No. 3, pp. 46–49, March, 1985.     

Experience with the industrial use of refractory concrete

Summary At KMK (Kuznets Steel Combine) extensive tests were made to fit various furnace parts with concrete containing Portland cement and aluminous cement, and also magnesia concretes containing sulfuric-acid bond.The concrete blocks and monolithic linings in a number of places exhibit advantages over brick structures.Concrete blocks behaved successfully in the air heaters, in the walls of heat-treatment furnaces for sheet rolling, in the covers of charging windows of open hearths, in the covers of charging traps of coke batteries, and in the dampers of periodic kilns for firing refractories.Concrete insulation was successfully applied to beam pipes.Experiments to use concrete to line the upper parts of soaking pits of blooming mills were unsuccessful.     

Mixtures of a base composition: Consumable lining of tundish ladles of continuous casting machines

Work on creating a refractory mixture of a base composition for consumable linings of tundish ladles of continuous casting machines is described. Various binders for mixtures deposited on the working lining of the tundish ladle by guniting have been tested. The endurance of a consumable lining based on periclase with an elevated content of CaO was 5 heats on a CCM of an electric steelmaking shop.Translated from Ogneupory, No. 4, pp. 28 – 30, April, 1996.