Under electric steel smelting workshop (ESSW) OAO Volzhskii Pipe Plant operating conditions the evolution of design and life of oxide-carbon refractories produced and supplied by OAO BKO in the period 2004 -2008 is followed. Operation of the working refractory lining layer of 150-ton steel-pouring ladles of ESSW furnace-ladles is analyzed, and the main areas for improving refractory composition and lining design are determined.The electric steel smelting workshop (ESSW) of OAO Volzhskii Pipe Plant (OAO VTZ) with a capacity of 900 thousand tons of steel per year provides the requirement of the enterprise for steel pipe manufacture. The modern electric steel smelting equipment includes the following units: an arc steel smelting furnace with a melt weight of 150 tons, water-cooled panels and roof, window delivery of metal; two furnace-ladle units (FLU) for finishing melt with respect to chemical composition and temperature with introduction of artificial slag and blowing with argon; a yard for steel-pouring ladles with a capacity of 150 tons in an amount of seventeen units; a steel vacuum degassing installation (VD-process); three four-stream units for continuous billet casting of the curvilinear type. Use of advanced technology and highly efficient equipment makes it possible to obtain high quality steel billets with an ultralow content of harmful impurities and gases.After introduction in 2000 of an oxide-carbon lining for steel-pouring ladles specialists of OAO VTZ started to attempt to improve the quality specifications for smelted steel and to reduce its cost. Intensification of production operations and steel processing under ESSW OAO VTZ conditions (argon blowing, steel vacuum degassing) lining service conditions in metallurgical units became complicated. The process of vacuum degassing of steel, active movement of metal and slag as a result of bottom blowing, created particularly severe service conditions for refractories in steel-pouring ladles, caused intense action on the oxide-carbon linings of a high temperature (up to 1720°C), corrosive molten slags, variable gas atmospheres, and increased thermomechanical loads. The requirement for completion of alloying, deoxidation, homogenizing metal with respect to chemical composition and temperature markedly increased the metal dwell time in ladles.Expenditure on repair and assembly of linings was a considerable part of the cost of pipe steel production. A reduction in specific expenditure in the consumption of refractory materials and an increase in the service life of linings of metallurgical units will make it possible to increase the operating efficiency of ESSW OAO VTZ. An increase in the life of trouble-free operation of linings is provided by improved technology and increasing the technical property indices and quality of refractories used, continuous observation of the design of the lining of the working layer providing uniform wear of all lining elements.The scientific and practical research center for improving technology and production (TsSTiP) of OAO...

Periclase-carbon linings made from objects supplied by OAO Borovichi Refractory Combine have been tested under operating conditions of converter workshop No. 2 at OAO NLMK in 2007 -2008 There is comparative analysis of linings and directions for improving refractory composition are determined.Specialists of OAO Novolipetsk Metallurgical Combine are devoting increased attention to the quality and reduction in cost of smelted steel. Intensification of production operations during the manufacture and processing of steel (argon blowing, chemical heating complicates the service conditions of refractory linings in metallurgical units: converters, steel-pouring ladles, electric furnaces, furnace ladle devices. The cost of refractory linings made from oxide-carbon refractories and operating in regimes of the intense action of high temperature, molten metals and slags, various gas atmospheres, mechanical loads, and also expenditure on repair and maintenance, contribute a considerable part of the cost of output. The service conditions for lining a converter in CW-2 of OAO NLMK are provided below:

The main areas of activity of OAO BKO (Open Joint Stock Corporation Borovich Refractory Combine) for the production and supply of sets of oxide-carbon refractory objects and subsidiary materials intended for the working layer of metallurgical units are considered. Results for the operation of the refractories supplied to metallurgical units, and prospects for joint work for increasing the operating life of linings are presented.Specialists of OAO BKO have developed and are constantly improving oxide-carbon refractories intended for lining steel-pouring ladles, converters, furnace-ladle units for extra-furnace processing of steel, and other metallurgical production units. The consumers of this production are numerous Russian metallurgical enterprises: OAO Severstal', OAO NLMK, OAO ChMK, OAO VTZ, OAO AvtoVaz, and many others. Since 2006 within the framework of a joint enterprise OAO BKO has produced oxide-carbon refractories in the PRC. The production capacity of the joint enterprise is about 30,000 tons per year. The Chinese shareholders also have their own plant for melting magnesite which is a favorable fact in the production of oxide-carbon refractories, since only periclase of the highest quality is used.The technology of oxide-carbon refractory production in the joint enterprise is determined by OAO BKO specialists in relation to service conditions in some consumer enterprise. Monitoring of quality is carried out in China by OAO BKO specialists.An increase the life of accident-free operation of linings is provided by a combination of technology with an increase in the technical property indices and the quality of the refractories used, continuous optimization of the lay-up design for the lining working layer providing the same life for all lining elements and uniform wear. The comprehensive solution of the problem for oxide-carbon refractories makes it possible to accomplish further improvement in physicochemical and operation properties of objects, to increase the life of the structural elements of refractory linings, and economic steel production. As a result of selecting the optimum grades for different areas of steel-pouring ladle linings, based on continuous engineering and monitoring operation of units, the life of the lining working layer supplied by OAO BKO satisfies the operating conditions of consumers, and provides guaranteed commitments.In a combined lay-up for lining the walls there is use of periclase-carbon objects grade PU-4AS and periclasespinel-carbon wall items grade PShU-45 and PShU-50, that are a new development of OAO BKO and serve as a replacement for the widely used corundum-periclase-carbon refractories. High-purity materials are used during the manufacture of objects: fuzed coarsely-crystalline periclase, fuzed aluminomagnesium spinel, fuzed corundum, coarse-flake graphite, combined antioxidizing addition Al met + Si and a combined organic binder. In preparation of the mix the polyfraction grain size composition of periclase and corundum is selected and introduced in an amount that i...

Properties are provided for oxide-carbon refractories produced by OAO BKO, used for lining various zones of steel-pouring ladles and converters. The dynamics of lining life for a OAO NLMK 350-ton converter, executed with refractories produced by OAO BKO, are demonstrated.The crisis year of 2009 brought changes in metallurgical production. A sharp and repeated fall in the price of ferrous metals and rolled product made steel producers reconsider plans of the development of production in the direction of greater profit. Open-hearth production was finally closed down in OAO Severstal'; the open-hearth workshop was closed in OAO Ashinsk Metallurgical Plant, etc. Contemporary and innovative technology is replacing outdated methods.Even higher specifications are laid down for the refractory objects in lining metallurgical units, which compels OAO BKO refractory workers to steadily improve oxide-carbon refractories, produced currently in contemporary production in China. From 2006 OAO BKO refractories are favorably recommended for lining steel-pouring ladles, converters, furnace-ladle devices for extra-furnace treatment of steel, and other steel smelting production units.The improvement in oxide-carbon refractories is complex in nature and combines several areas simultaneously. Use of the latest achievements in science and technology, the OAO BKO scientific center (technology and production are improved in the center) using contemporary equipment carries out research on the physiochemical and technical property indices for refractories. The research work attracts specialists and refractory technology faculties of institutes of St Petersburg, Belgorod, and Moscow. In production there is use of high quality mixing and pressing equipment from leading world companies.In order to provide production of high quality raw material is use of the resources of Chinese stockholders, having their own plant for melting magnesite, which makes it possible to use in the production of periclase with purity up to 99%. Material filling of the charge and technology for producing oxide-carbon refractories in a joint enterprise is determined by OAO BKO specialists in relation to the service conditions of the consumer. Quality control of refractories is carried out by OAO BKO specialists. Use of contemporary methods for logistical control makes it possible to shorten the time for movement of a load from production to the consumer to three weeks, thereby making it possible to track the location of a load daily.In order to provide uniform life for all lining elements and their uniform wear there is optimization of lining design combined with choice of refractories. As a result of selecting the optimum grades of objects fro different zones of a lining in a steel-pouring ladle, based on continuous monitoring of unit operation and realization of the zonal principle of lining construction, its life entirely satisfies consumer operating, providing the guaranteed commitments of the supplier.The plant produces objects of grades PU-1, PU-6 (Table 1) for ...

The interrelation between the content of carbon and silicon carbide and the properties of carboxylated refractories (porosity, mechanical strength, heat resistance, resistance to the action of blast-furnace slag) is studied. Dependences of the properties of carboxylated refractories on their material composition are plotted.The quality of steel in metallurgy is often improved by treating cast iron, i.e., desulfurization, dephosphorization, and desiliconization, which are performed in mixers, casting ladles, and oxygen-blown vessels [1]. The functional layers of the linings of this equipment are primarily made of refractories based in the Al 2 O 3 -SiC-C system, which have replaced the earlier used high-alumina refractories and increased substantially the service life of the linings [2, pp. 248 -259]. Refractories with Al 2 O 3 -SiC-C composition are not roasted and are produced with the use of high-alumina raw materials (bauxite, corundum of different quality), silicon carbide, graphite, and tar with addition of functional additives [3].In order to improve the parameters of the properties carboxylated refractories are enriched with carbon. Carbon decreases the penetration of slag into refractories, which is associated with its low wetting with slag and the capacity to reduce iron oxides in the slag, which raises the viscosity and the melting temperature of the latter [4]. Carbon is usually introduced into the refractory in the form of graphite and tar. It is assumed that the gaseous products of carbon oxidation (CO and CO 2 ) in a carboxylated refractory fill the pores and create backpressure that hinders the penetration of slag. Growth in the carbon content is accompanied by increase in the slag resistance of carboxylated refractories [5]. The content of carbon in the refractories and its protection from burning are determined by the production parameters of the refractories and the service conditions in linings of metallurgical equipment.In the course of the study the carbon content was varied from 4 to 8 wt.% by changing the amount of introduced graphite at a constant amount of tar. The content of silicon carbide was varied within 10 -14 wt.%. The components were introduced into the composition of the finely milled part of the charge. The time of vibromixing was 25 min. The mixture prepared left no remainder on a sieve with a cell size of 0.063 mm. We used high-quality components of domestic and foreign producers. The plasticizer was a composition with a high residual carbon content, which had been developed by the department of chemical technology of high-temperature materials. The mixtures were prepared in a tempering mill with maximum charge of 6 kg; the preparation time was 20 -25 min. The tests were performed for molded cubic specimens with an edge of 50 mm, which had been heat treated preliminarily at 300 ºC with 15-h hold. The results of the tests were plotted in the form of linear dependences on the domains of designed compositions for 9 points using the MS Excel 2003 medium.The ultimate compressive s...