Selecting stable mortars for lining intermediate ladles of continuous steel casting plants

Conclusions The prolonged casting of killed carbon steel requires the use of high-alumina mortar VT-1, slaked with water; prolonged casting of rimmed and corrosive (manganese type) steels requires high-alumina mortar VT-1 slaked with orthophosphoric acid; the assembly of composite elongated nozzles in combination with batcher inserts for casting two or more heats of ordinary rimmed steels 08KP requires corundum type mortars (V-6).Translated from Ogneupory, No. 6, pp. 20–25, June, 1970.     

Physicochemical processes during the contact of steel with casting nozzles

Conclusions The results of physicochemical processes taking place in casting nozzles depend on the content of the steel of chemically active components and the composition of the refractory. An examination of the phase diagram of the systems forming contact zones in the nozzles enabled us to obtain a nomogram for determining the degree of erosion or tightening up of the nozzles in the intermediate ladles as a function of the composition of the refractory material and the content of aluminum in the steel being cast.In order to explain the stable feed of metal from the intermediate ladels in continuous steel casting plant in the crystallizer we recommend the casting of rimmed steel through magnesite nozzles, killed steel with a content of less than 0.01% aluminum through zircon nozzles, and containing more than 0.01% aluminum through fireclay (35–40% Al₂O₃).Translated from Ogneupory, No. 6, pp. 33–38, June, 1973.     

Service of elongated composite nozzle batchers and nozzles under the batcher insert for continuous steel casting

Conclusions High-alumina composite elongated batcher nozzles containing 62–64% A1₂O₃ satisfy the requirements of casting killed steel. They are being introduced in the continuous steel casting plant of the electric steel casting shop of the Novolipets Metallurgical Factory.The casting of metal in a crystallizer needs to be done through elongated batching devices under a cover, with the maximum degree of sealing and proximity of the metal surface to the tapping hole of the nozzle.Prolonged casting of the unkilled steels type ST2KP and 3KP should be done through elongated high-alumina nozzles containing 80–82% A1₂O₃ with corundum batcher inserts.The following took part in the project: S. A. Krulevetskii, E. I. Ermolaeva, V. V. Parfent'eva, L. N. Baskakova, T. K. Chirkina, N. T. Nikokoshev, Yu. A. Kravchenko, and G. B. Lesokhin.Translated from Ogneupory, No. 2, pp. 21–24, February, 1969.     

Making gate valve refractories for steel ladles using GK alumina

Conclusions A technology was developed for making articles for the gate valves of steel casting ladles ensuring high service factors. It was found possible to use high-alumina chamotte instead of corundum.Translated from Ogneupory, No. 1, pp. 16–18, January, 1980.     

Developing ramming compounds for monolithic linings in steel ladles

Conclusions It is possible to use natural loamy sands with a refractoriness about 1650°C and containing 2.5–4.5% Al₂O₃, and also mixtures of quartz sands and 15% fireclay for rammed linings of steel ladles applied with sand slinger. The relationship between the wear of these linings in service and the compounds concentrations of alkali metal oxides was determined in the research.A composition was developed for a compound based on pure quartz material (Ovruch quartzites) with an addition of 15% fireclay. Production of the compounds has started at the Krasnogorov Refractories Plant. The use of the new compounds has increased the life of 100-ton ladles at the Dzerzhinskii Factory from 12 to 18–20 pourings.Translated from Ogneupory, No. 1, pp. 6–10, January, 1979.     

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.     

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.     

Steelcasting and intermediate ladles for equipment for the continuous casting of steel

Conclusions The life of linings in large ladles depends on the grade of steel, the amount, chemical composition and consistency of the slag.The intermediate ladle made in the factory ensures reliable operation during the casting of metal by the continuous steel casting operation.Heating the intermediate ladle to 1100–1200°C by means of compact burners, working on coke gas, and new designs for cooled stoppers and stopper devices greatly reduces slab loss.In the process of evaluating the casting of transformer steel the loss due to nonmetallic inclusions was greatly reduced, but not completely eliminated.Further work must be done to explain the causes of the formation of slag inclusions and methods of handling the problem.     

Production and use of low-fired stopper tubes

Conclusions Fireclay stopper tubes made by semidry pressing and fired at 800–900° C are suitable for service in steel casting ladles in the open-hearth departments of NTMK. Compared with ordinary low-fired stopper tubes they are more spalling resistant and less thermal conducting.The use of low-fired stopper tubes is economical owing to the reduction in loss and fuel consumption in firing.Translated from Ogneupory, No. 5, pp. 8–10, May 1967.     

Production and use of periclase-chromite concrete parts for the linings of high temperature ladles

Conclusions A method has been developed for production of standard periclase-chromite concrete parts for the linings of high temperature ladles for teeming steel and ferroalloys. The parts have high strength and low porosity and are practically shrinkage-free.The life of periclase-chromite concrete parts in the steel teeming ladles of Chelyabinsk Metallurgical Plant is about four times greater than that of fireclay parts, in Red October Plant practically the same as that observed with the use of high alumina parts, and at Chelyabinsk Electrometallurgical Plant it was higher only in the upper portion of ladles in comparison with that obtained with the normally used fired periclase parts.During service in ladles the parts do not spall, become encrusted at a metal temperature of 1620 °C, do not become encrusted at 1790°C, and at 2200°C are eroded by slag.Translated from Ogneupory, No. 7, pp. 16–20, July, 1982.     

High-alumina refractories for lining steel ladles (discussion)

Conclusions We developed and evaluated, in industrial conditions, a technology for the production of unfired, mullite-corundum refractories, and also fired, mullite-siliceous refractories with additons of chrome ore for lining steel ladles.The life of the 150-tonne steel ladles, with steel processing outside the furnace, when the ladles were lined with the experimental unfired mullite-corundum refractories, equals the life of the ladles lined with similar, industrial fired bricks. The same resistance (on average 20 pourings) was possessed by the ladles lined with the experimental mullite brick of improved quality. The resistance of the ladles lined with the experimental, fired mullitesiliceous refractory with the chrome additive was 26–27 pourings.To explain the effectiveness of using the newly developed refractories in the linings of steelcasting ladles, it is necessary to continue testing them in different metallurgical enterprises.The first part of the discussion was published in No. 8, 1988, and it was continued in Nos. 9–12, 1988, and Nos. 1–3 and 5, 1989.Translated from Ogneupory, No. 7, pp. 4–8, July, 1989.     

High-durability plugs for the ladles of continuous steelcasting plant

Conclusions The Krasnyi Oktyabr refractories plant has produced SP-14 and SP-11 type conical chamotte plugs containing 39.77% Al₂O₃ + TiO₂.The SP-14 plugs were tested in the main ladles of the continuous steelcasting equipment of the Novo-Lipetsk metallurgical plant, the SP-11 type in pony ladles at the Sarkanais Metallurgs plant.The tests demonstrated the superiority of these plugs, i.e., they reduced the proportion of unregulated castings from 23.2 to 3.4% in the main ladles and lowered wear in the pony ladles by 8–9%. These conical chamotte plugs can be recommended, therefore, for use in the main and pony ladles of continuous steelcasting equipment.Translated from Ogneupory, No. 6, pp. 3–4, June, 1974.     

Wettability of aluminosilicate refractories with molten steel

Conclusions An increase in the Al₂O₃ content of the base causes the wetting angle of steel 10kp to increase with an increase in the temperature from 1490 to 1620°C.Chromium-nickel steel wets refractories to a greater degree than rimmed steel. In this case the wetting angle is largest on mullite-corundum refractories containing 75–78% Al₂O₃.The introduction of small amounts of modifying additives in the form of MgO and Cr₂O₃+ ZrSiO₄ into mullite-corundum and corundum refractories causes the wetting angle to increase by 7–10° and helps to increase the resistance of the refractory materials to the action of rimmed steel.Translated from Ogneupory, No. 4, pp. 53–56, April, 1978.     

Introducing “Orion” equipment for mechanized guncreting of steel ladles

Conclusions Industrial operation in steel factories of the Orion complex has shown the effectiveness of the plant and of mechanizing the guncreting of steel ladles. The average life of the lining in ladles was increased by 25–50%, the maximum life of 200-ton ladles at the Rustav factory having been brought to 52 heats. A reduction has been achieved in the specific consumption of ladle refractories equal to 1.7–3 kg/ton of steel. At Magnitogorsk they have increased the throughput capacity of steel melting bays by 3% with a reduction in the ladle stock of 11%.Translated from Ogneupory, No. 6, pp. 19–22, June, 1981.     

Increasing the resistance of stoppers in large steel-casting ladles

Conclusions The use in large ladles of stoppers with diameters of 205 mm, with a porosity of 17–20%, and stopper tubes with a porosity of 20–24% ensures normal operation of the stopper during the whole of the casting cycle.The dimensions of the socket brick GK-8 for the bigger stopper do not have to be altered.According to the experience of ChMZ and NTMK (Nizhne-Tagil'sk Metallurgical Combine) the temperature of initial deformation of stoppers without injury to their resistance can be reduced to 1320°C.The desirability of determining this property for stoppers should be established by the refractory institutes.Existing GOST 5500-50 was not fixed for the widely introduced semidry pressing of stopper equipment and changes in the technology of steel-casting.It is necessary to accelerate the incorporation of resolutions made at the All-Union Conference of Refractory workers in 1960 on re-examination of GOST 5500-50.     

Dense zircon insert-batchers for intermediate ladles on continuous steel casting plant

Conclusions A technology was developed for making dense zircon insert-batchers with an open porosity of up to 10%. The insert wear is less than 1 mm during the hot time. They satisfy the property requirements for continuous casting of killed carbon steel deoxidized with aluminum in amounts of up to 300 g/ton.Translated from Ogneupory, No. 3, pp. 11–13, March. 1973.     

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.     

Cast magnesia-spinel concrete linings for steelcasting ladles

Conclusions The magnesia-spinel concretes developed by the writers possess good mobility, thermal-shock resistance, volumetric stability, and low porosity. The concretes settle without additional compaction.A simple technology was developed for the production of cast concrete linings in steelcasting ladles. In transformer steel production the lining of 25-ton recasting ladles lasted six times longer than a chamotte brick lining and the specific consumption of refractories was four times lower; in 35-ton steelcasting ladles a lining of concrete MShG-15 lasted twice as long as a chamotte brick lining and the specific consumption of refractories was 1.3 times lower.An installation was devised for the production of cast concrete linings in steelcasting ladles.Translated from Ogneupory, No. 5, pp. 9–15, May, 1977.     

Kyanite and fireclay from Vietnam

Conclusions The sample of kyanite studied represents a valuable raw material suitable for making high-alumina refractories. It can be used to make mullite-siliceous brick whose properties, especially when the ore is enriched by the wet method, correspond to those for mullite goods (GOST 24704-81). The Al₂O₃ content in the refractories can be increased to the level of mullite by adding alumina to the batch. The kyanite goods, in terms of service in steel casting ladles, are superior to firebrick (by a factor of 1.5).The fireclay is suitable as a bond in the batch for high-alumina goods and for making firebricks class C.Translated from Ogneupory, No. 5, pp. 20–23, May, 1991.     

High-alumina low-fired products based on kyanite — Sillimanite concentrate

Conclusions A technology was developed for making high-alumina low-fired products using kyanite-sillimanite concentrate with a sulfite-lye or orthophosphoric acid bond.The possibility was established of using low-fired brick at service temperatures of up to 1500°C. The tests of these high-alumina products in steel casting ladles of different capacities and in industrial kilns with different service conditions enabled us to establish the most effective locations of their use.Translated from Ogneupory, No. 6, pp. 6–9, June, 1971.