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.     

Service of refractories in the continuous casting of 100 ton converter heats

Conclusions Refractories for steel-casting ladles used at present in the converter shop of the Novolipetsk Factory can be used for casting 100-ton heats. However, it is necessary to increase the resistance of the ladle linings.Ladle bricks, stopper tubes, and zircon nozzles provide reliable casting of 3–4 heats in series without replacing the intermediate ladle.To provide reliable covering of the jets where necessary it is recommended that use be made of highalumina plugs for intermediate ladle stoppers.Translated from Ogneupory, No. 7, pp. 37–41, July, 1968.     

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.     

Stopper tubes with better spalling resistance

Conclusions An improvement in the grain-size composition of the body and a reduction in segregation of the body when it is poured into the press molds permitted us to increase the spalling resistance of stopper tubes and to improve their reliability in service. Simultaneously there was a reduction in the percentage loss due to cracks in drying and firing.Translated from Ogneupory, No. 4, pp. 6–8, April, 1967.     

Semiacid ladle brick based on low-fired chamotte,quartz sand,and Ch1PK clay

Conclusions Dense semiacid products based on low-fired chamotte can be obtained by adding 15–30% quartz sand to the batch. The articles need to be fired at 1260±30–40°C. Firing at temperatures above 1300° and below 1230 even by 20–40° reduces the apparent density and after-expansion of the products.Preliminary testing in service showed that the wear of the semiacid ladle brick is 10% less than that of dense kaolinized brick.Using the proposed technology it is necessary to produce large batches of semiacid refractories, observing the optimum parameters of their manufacture in order to establish the economic effectiveness and advantages of organizing the industrial production of such articles.Translated from Ogneupory, No. 8, pp. 9–15, August, 1969.     

Increasing wear resistance of stoppers for 140-ton steel-casting ladles

Conclusions Among the principal reasons for partial or substantial leaking of the metal stream are the following: burning away of the stopper, breaking off of the spherical part of the head, wear and tear of the head and sleeve bricks and opening up of the seams through deformation of the rod.The stoppers burn away on account of a great deal of wear and tear in the pipes, erosion of the seams, formation of cracks in the pipes and head and deformation of the stopper on account of the rod becoming too hot.The amount of slag in the ladle is one of the main factors for corrosion wear in stopper pipes. The aggressive action in the slag increases as the temperature of the metal and casting time are increased.Breaking off of the spherical part of the head during the first stopper opening due to the formation of skull between the stopper saddle and head can be avoided by using a graphite filling.Insulation of the stopper rod reduces the temperature during casting by 150–300°. The use of good quality mortar in assembling stoppers reduces the erosion of seams, while the use of a high-alumina putty prevents wear in the pipes.     

Sighting tubes for temperature measurements in open-hearth roofs

Conclusions Service tests of sighting tubes made from corundum and magnesia spinel showed that a gas permeability of 0.0009–0.00006 liter·m/m²·h·mm water guarantees the measurement of temperature with optical pyrometers without interference from the gaseous atmosphere.The maximum life of sighting tubes placed in the roof of open-hearth furnaces is obtained only when the articles are fixed at a distance not exceeding 40–50 mm in front of the roof surface; the minimum life is possessed by those products protruding into the furnace space by a magnitude equal to 3 diameters. The greatest resistance is shown by articles made from magnesia spinel.The sighting spinel, thin-walled tubes can be used for short control temperature checks of the roof of open-hearth furnaces; corundum and spinel tubes can be used for automatic measurements of temperatures in periodic kilns for firing refractories.Translated from Ogneupory No. 6, pp. 7–10, June, 1968.     

Ceramics for furnaces for growing crystals by the Verneuil method

Conclusions The writers developed optimal compositions and the technology for corundum tubes of high thermal strength for furnaces for growing monocrystals. The durability of the fired tubes was 58–104 days and that of unfired tubes 51–82 days.The technology is based on the use of high-fired granular corundum filler, not more than 40% fine-ground components, and 20% added- Al₂O₃ for fired tubes and 5% added H₃PO₄ for unfired tubes.Translated from Ogneupory, No. 8, pp. 39–44, August, 1976.     

Two-piece nozzle-batchers for continuous casting of electrical-engineering steel

Conclusions A design and production technology were developed for making fireclay two-piece elongated steelcasting nozzle batchers with an apparent porosity of 14–17%. The resistance of the nozzles is satisfactory and they form a satisfactory jet, despite the retarding action of the stopper plug.The nozzles are being introduced at the Novolipetsk Metallurgical Factory and their production organized at the Semiluki Refractories Factory. The use of elongated nozzles and improved insulation of the working zone in the crystallizer during the continuous casting of electrical-engineering and carbon steel permitted a substantial improvement to be made in the purity of the surface of the cast slabs and the quality of the metal, and also yielded 46,000 rubles annual savings.Translated from Ogneupory, No. 4, pp. 4–6, April, 1967.     

Granulation of particulate oxide materials

Conclusions The improved technology for granulating particulate oxide materials using the grains of inoculator seeds makes it possible to reduce the period of granulation and to increase the yield of the final granules. The waste products obtained during production of flaky (platelike) corundum can be used as the inoculator grains. In order to obtain granules having an ellipticity not exceeding 0.5–0.7 mm, the optimum size of the inoculator grains is 1–2 mm.The inoculator grains obtained from the low-fired (undersintered) material has advantages over the densely sintered materials from the standpoint of improved internal structure of the granules. We established the optimum quantity of the inoculator grains for obtaining granules measuring (20±3) mm in diameter using a granulator having a diameter of 1000 mm with minimum irretrievable waste products during the initial period of granulation.We studied the growth kinetics during seedless granulation and during granulation with an inoculator. It was shown that densification of the granules occurs during granulation. We determined the main physical and mechanical properties of the granules obtained by granulating on the inoculator grains and by seedless granulation and established the optimum composition of the binding solution (binder) incorporating a phosphate-containing component as strengthening agent.Translated from Ogneupory, No. 6, pp. 10–13, June, 1989     

Making refractory products from Arkalyksk clays

Conclusions With the use of Arkalyksk clay in existing conditions of refractories production at the ChMZ plant for obtaining grog with a water absorption of up to 5–6% it is necessary to add 25% plastic clay of the Buskul'sk type.The introduction into use of a rotary furnace will permit the firing of refractory Arkalyksk high-grade clays without additions, which should increase the life of the ladle and stopper refractories.     

Making siphon and ladle products from Arkalyksk clay

Conclusions It is possible to use Arkalyksk clay in the bonding part of the batch in amounts of 3% for preparing siphon tubes with physicochemical properties corresponding to the requirements of GOST.With combined firing of experimental siphon tubes and ladle brick it was possible to increase the firing temperature by 50°C, as a result of which the porosity of the ladle brick drops 1%, and the wear 2–3 mm/heat. The experimental siphon tubes tested for casting steel had a satisfactory resistance.Translated from Ogneupory, No.2, pp. 1–3, February, 1970.     

Corrosion resistance of aluminum and its alloys under the operating conditions of viscose manufacturing gas conduits

Conclusions In conformity with the data obtained, technical aluminum, grade A7 (or AD00) can be recommended for making discharge tubes at viscose fibre plants.Considering that discharge tube lines are expensive equipment designed for long-term use, it is advisable to use a supplemental polymeric protection for the aluminum, for example, chemically resistant, cold-setting sealing agents.The use of conduit tubes of 10.5 mm thick aluminum having a polymer protective coat instead of wooden ones will make it possible to reduce expenditures for making them by a factor of 2–3, and will essentially eliminate costs for repair work.Translated from Khimicheskie Volokna, No. 5, pp. 17–19, September–October, 1988.     

Use of a nozzle in particle acceleration by a flow of gas detonation products in tubes

Experimental results on the acceleration of inert spherical particles(30–170 µm in diameter) by gas detonation waves in tubes with nozzles are presented. It is shown that divergent nozzles increase the particle velocity by up to40%. Laser visualization was applied to obtain streak records of particle motion.Translated from Fizika Goreniya i Vzryva, Vol. 32, No. 5, pp. 21–29, September–October, 1996.     

Manufacture of stopper tubes by semidry pressing at the “Red Star” Factory

Conclusions The Red Star Factory has developed the production of stopper tubes on a press designed by I. F. Yurchenko.A scheme has been developed for the manufacture of stopper tubes of different grades by semidry pressing.     

The service of refractories in stream treatment of metal with continuous casting of the steel

Conclusions The service of monoblock stoppers, controlling nozzles, and submerged nozzles with stream blowing of the metal with gas was studied. The desirability of use of a monoblock stopper with a hole in the lower portion and a thread in the upper for treatment of the metal with gas in the intermediate ladle was concluded.The service of straight-through submerged nozzles under conditions of blowing was studied and means of increasing their life were noted.Translated from Ogneupory, No. 2, pp. 47–50, February, 1984.     

Potentiometric determination of benzenesulfonic acid in technological solutions and on the surface of fillers

Conclusions Procedures have been developed for the potentiometric determination of BSA content of impregnating baths and on the surface of fillers in the technological process of making chemically resistant tubes.The procedures proposed are characterized by accuracy and reproducibility of results.A study of the change in BSA content and moisture content at various stages of the technological process of making chemically resistant tubes has shown a change in the figures for these indices with the storage time of the starting BSA and of the impregnating solutions, and with filler nonuniformity.Translated from Khimicheskie Volokna, No. 1, pp. 56–57, January–February, 1987.     

The effect of viscosity on the detonation stability of diethylene glycol dinitrate

It was established that increasing the viscosity of diethylene glycol dinitrate by addition of 3% colloxylene leads to a 20% decrease in the critical diameter of high-speed detonation of liquidHE in glass tubes. In thin-walled paper tubes, end-on camera streak records show the appearance of a near-wall unreacting layer, whose thickness increases as the front moves along the charge.Translated from fizika Goreniya Vzryva, Vol. 32, No. 1, pp. 111–114, January–February, 1996.     

Record-breaking durability of quartz protecting tubes for steel teeming tested under service conditions

Results for a pilot batch of quartz protecting tubes for steel teeming fabricated by a ceramic castable technology and tested at the Novolipetsk Iron and Steel Works (NLISW) are reported. The average durability of tubes tested was shown to be 5.2 heats (maximum 9), which is 15% higher than that of corundum-graphite protecting tubes available from the Vesuvius JSC. The cost of corundum-graphite tube is 5 times the cost of quartz tubes.__________Translated from Novye Ogneupory, No. 12, pp. 17 – 18, December, 2004.     

Experimental study of burn-up regimes in mixtures of C2H2+O2+N2 in closed tubes

An experimental study is performed of burn-up regimes in C₂H₂+O₂+N₂ acetylene mixtures in closed volumes formed by tubes with sealed ends and sections of 50–80 cm² for various initiation methods. Conditions are determined for detonation-free burn-up, as well as for propagation of a regime intermediate between combustion and detonation.Arzamas. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 2, pp. 43–46, March–April, 1992.