Krosakiharima Corporation Patent applications |
Patent application number | Title | Published |
20150368159 | MAGNESIA CARBON BRICK - In the present invention, the attempt was made to increase the denseness (to lower the porosity) of a magnesia carbon brick furthermore thereby providing the magnesia carbon brick having a high durability never found in the past. The magnesia carbon brick of the present invention comprises a magnesia raw material and a graphite, wherein the magnesia carbon brick contains the graphite with the amount thereof in the range of 8% or more by mass and 25% or less by mass and the magnesia raw material with the amount thereof in the range of 75% or more by mass and 92% or less by mass, the both amounts being relative to the total amount of the magnesia raw material and the graphite; as a grain size distribution of the magnesia raw material, the magnesia raw material having particle diameter of in the range of 0.075 mm or more and 1 mm or less is blended with the amount thereof being 35% or more by mass relative to the total amount of the magnesia raw material and the graphite, and a mass ratio of the magnesia raw material having the particle diameter of in the range of 0.075 mm or more and 1 mm or less to the magnesia raw material having the particle diameter of less than 0.075 mm is 4.2 or more; and an apparent porosity thereof after firing in reducing atmosphere for 3 hours at 1400° C. is 7.8% or less. | 12-24-2015 |
20150196954 | METHOD FOR USING UPPER NOZZLE - With a view to adding, to an upper nozzle formed with a bore having a shape capable of creating a less energy loss or smooth (constant) molten steel flow to suppress the occurrence of adhesion of inclusions and metals in molten steel, a gas injection function to thereby further suppress the occurrence of the adhesion, the present invention provides a method of using an upper nozzle configured to have a cross-sectional shape of a wall surface defining the bore, taken along an axis of the bore, comprising a curve represented by the following formula: log(r (z))=(1/n)×log((H+L)/(H+z))+log(r (L)) (n=1.5 to 6), where: L is a length of the upper nozzle; H is a calculational hydrostatic head height; and r (z) is an inner radius of the bore at a position downwardly away from an upper edge of the bore by a distance z. The method comprises using the upper nozzle in such a manner as to satisfy the following relationship: R | 07-16-2015 |
20140263483 | PLATE FIXING STRUCTURE AND PLATE - Provided is a plate fixing structure which is usable in a concavo-convex fitting technique for fitting with respect to a fitting concave or convex portion provided in a plate-receiving metal frame, and capable of easily achieving an alignment between the fitting convex portion and the fitting concave portion, and a plate for use with the fixing structure. The plate | 09-18-2014 |
20130334263 | REFRACTORY MATERIAL AND CASTING NOZZLE - A refractory product includes CaO component-containing refractory particles and MgO component-containing refractory particles. The refractory material contains, a chemical composition measured after it has undergone heating in a non-oxidizing atmosphere at 1000° C., one or more of the following metal oxides B2O3, TiO2, V2O5, P2O5 and SiO2 in a total amount of 0.1 to 5.0 mass %, and free carbon in an amount of 2 to 35 mass %, with the remainder including CaO and MgO whose mass ratio (CaO/MgO) is in the range of 0.1 to 1.5. In microscopic observation performed at room temperature on the refractory material which has undergone the above heating, an inorganic film comprised of CaO and the one or more metal oxides is formed in at least each CaO surface of the refractory particles each containing either one or both of a CaO component and an MgO component, with a thickness of 0.1 to 25 μm. | 12-19-2013 |
20130288879 | HIGH-RIGIDITY CERAMIC MATERIAL AND PRODUCTION METHOD THEREFOR - Disclosed is a boron carbide-based ceramics material which has a high density and a high specific rigidity, but additionally with excellent processability, and a production method for the boron carbide-based ceramics material. Specifically, the high-rigidity ceramics material contains boron carbide in an amount of 90 to 99.5 mass %, wherein at least silicon, aluminum, oxygen and nitrogen coexist in a grain boundary phase between crystal grains of the boron carbide. This high-rigidity ceramics material can be produced by a method comprising: preparing a boron carbide powder, and, as a sintering aid, one or more selected from the group consisting of an oxide, a nitride and an oxynitride of silicon, an oxide, a nitride and an oxynitride of aluminum, and a composite oxide, a composite nitride and a composite oxynitride of aluminum and silicon, in such a manner as to contain all of Si, Al, O and N; and subjecting the boron carbide powder and the sintering aid to mixing, forming and sintering. | 10-31-2013 |
20130284770 | SLIDING NOZZLE PLATE AND SLIDING NOZZLE DEVICE USING THE SAME - Disclosed is a sliding nozzle plate (composite sliding nozzle plate) ( | 10-31-2013 |
20130059719 | Aluminum oxycarbide composition, production method therefor, and refractory material - It is an object to provide an aluminum oxycarbide composition capable of suppressing oxidation of Al | 03-07-2013 |
20120217271 | MOLTEN METAL DISCHARGE NOZZLE - Provided is a molten metal discharge nozzle which has a bore configuration capable of creating a low-energy loss and smooth (stabilized) molten metal flow to suppress the occurrence of an adhesion matter. In the molten metal discharge nozzle, a radius r(0) of an upper end ( | 08-30-2012 |
20120141740 | SLIDING NOZZLE PLATE - The present invention provides an SN plate capable of being formed in a large size while using a highly corrosion resistant and highly thermally expansible refractory product. In the SN plate of the present invention, a specific refractory member | 06-07-2012 |
20120100982 | CORDIERITE-BASED SINTERED BODY - The present invention is intended to drastically improve a precision polishing characteristic of a cordierite-based sintered body which has low thermal expansibility, high dimensional long-term stability and high rigidity (high elastic modulus). The cordierite-based sintered body comprises cordierite as primary components, and one or more selected from the group consisting of La, Ce, Sm, Gd, Dy, Er, Yb and Y in an oxide-equivalent amount of 1 to 8 mass %, without any crystal phase other than a cordierite crystal phase. A mass ratio of primary components of the cordierite satisfies the following relations: 3.85≦SiO | 04-26-2012 |
20120035384 | ALUMINUM OXYCARBIDE COMPOSITION AND PRODUCTION METHOD THEREFOR - Provided is an aluminum oxycarbide composition production method capable of increasing a yield of Al | 02-09-2012 |
20110297707 | Anti-alumina-buildup refractories for casting nozzles - Disclosed is anti-alumina-buildup refractories for casting nozzles, which comprises a refractory aggregate including 20 mass % or more of CaO component, and 10 mass % or more of clinker particles each containing CaO as a mineral phase, on the basis of 100 mass % of the entire composition. At least a part of the surfaces of the CaO exposed from the surfaces of the corresponding clinker particles is formed with a CaCO | 12-08-2011 |
20110277951 | REFRACTORY MATERIAL, CONTINUOUS CASTING NOZZLE USING THE REFRACTORY MATERIAL, PRODUCTION METHODS FOR THE CONTINUOUS CASTING NOZZLE, AND CONTINUOUS CASTING METHODS USING THE CONTINUOUS CASTING NOZZLE | 11-17-2011 |
20110241267 | PLATE BRICK PRODUCTION METHOD AND PLATE BRICK - Disclosed is a method of producing a plate brick, which comprises: adding an organic binder to a refractory raw material mixture containing aluminum and/or an aluminum alloy; kneading them; forming the kneaded mixture into a shaped body; and burning the shaped body in a nitrogen gas atmosphere at a temperature of 1000 to 1400° C., wherein: when a temperature of a furnace atmosphere is 300° C. or more, the atmosphere is set to a nitrogen gas atmosphere; and when the temperature of the furnace atmosphere is 1000° C. or more, an oxygen gas concentration in the atmosphere is maintained at 100 volume ppm or less, and a sum of a carbon monoxide gas concentration and a carbon dioxide gas concentration is maintained at 1.0 volume % or less. This makes it possible to form a large amount of fine and uniform aluminum nitride in a plate brick to prevent microstructural degradation due to hydration caused by formation of aluminum carbide and suppress oxidation of a carbon bond so as to improve surface-roughening resistance. | 10-06-2011 |
20110240688 | IMMERSION NOZZLE - It is intended to uniform and straighten a molten steel stream flowing out of a discharge port of an immersion nozzle, and thus suppress mold powder entrapment in the vicinity of the immersion nozzle. The immersion nozzle comprises a tubular-shaped straight nozzle body formed to extend in a vertical longitudinal direction and adapted to allow molten steel from a molten-steel inlet provided at an upper end thereof to pass downwardly therethrough, and a pair of discharge ports provided in a lower portion of the straight nozzle body in bilaterally symmetrical relation and adapted to discharge the molten steel from a lateral surface of the straight nozzle body in a lateral direction. An inner surface of each of the discharge ports has, at least in part or in its entirety, a shape defined by a curved line along which an inner bore of the discharge port in a longitudinal cross-section of the immersion nozzle passing through respective centers of the immersion nozzle and the discharge port is gradually reduced in diameter in a direction from a start position to an end of the discharge port, wherein the curved line is represented by a diameter in the longitudinal cross-section of the immersion nozzle. | 10-06-2011 |
20110077340 | PLATE BRICK AND PRODUCTION METHOD THEREFOR - The present invention provides a plate brick having a low amount of generation of smoke and a gas with a pungent odor during use, and exhibiting high durability. A plate brick of the present invention is obtained by: adding an organic binder to a refractory raw material mixture containing 0.5 to 20 mass % of aluminum and/or aluminum alloy; kneading the mixture with the organic binder; forming the kneaded mixture into a shaped body; and subjecting the shaped body to a heat treatment at a temperature of 400 to 1000° C., wherein the plate brick is obtained without being impregnated with a carbon-containing liquid material comprising tar or pitch, after the heat treatment. The plate brick has a compressive strength of 180 MPa or more, and a weight-increasing rate of 1% or less as measured in a hydration test using an autoclave. | 03-31-2011 |
20110017784 | MOLTEN METAL DISCHARGE NOZZLE - Provided is a molten metal discharge nozzle capable of suppressing turbulence in a molten metal stream passing through an inner bore thereof, with a simple structure. A cross-sectional shape of a wall surface of the inner bore, taken along an axis of the inner bore, comprises a part or an entirety of a curved line expressed by the following formula: log(r(z))=(1/n)×log((Hc+L)/(Hc+z))+log(r(L)) (1), where: 6≧n≧1.5; L is a length of the nozzle; Hc is a calculative hydrostatic head; and r(z) is a radius of the inner bore at a position located a distance z downward from an upper end of the nozzle, wherein, in a graph where the distance z is plotted with respect to a horizontal axis (X-axis) thereof, and a pressure of molten metal at a center of the inner bore in horizontal cross-section at a position located the distance z is plotted with respect to a vertical axis (Y-axis) thereof, an approximation formula of a line on the graph is established without simultaneously including two or more coefficients having opposite signs, and wherein, on an assumption that the line is derived from an approximation formula based on a linear regression, an absolute value of a correlation coefficient of the line is 0.95 or more. | 01-27-2011 |
20100304951 | TAPHOLE MIX - It is intended to provide a taphole mix capable of forming SiC bonds with minimum of an excess and a deficiency in components thereof, and excellent in drillability. A fine particle fraction having a particle diameter of 75 μm or less is comprised of three components consisting of a silicon nitride-based material, a carbon-based material, and roseki, or comprised of the three component, and one or more selected from the group consisting of an alumina-based material, a silicon carbide-based material, a rare-earth element oxide-based material, clay, a high-purity silica-based material containing SiO | 12-02-2010 |
20100298109 | ZIRCONIA-MULLITE REFRACTORY RAW MATERIAL AND A PLATE BRICK - Provided is a zirconia-mullite refractory raw material which is less likely to undergo alternation and microstructural degradation under high-temperature conditions, and low in thermal expansion rate, so as to have thermal shock resistance and corrosion resistance. The zirconia-mullite refractory raw material comprises crystalline zirconia and mullite as primary components, with the remainder being corundum and/or a matrix glass, wherein the crystalline zirconia includes a eutectic zirconia crystal having a grain size of 1.0 μm or less, and has a maximum grain size of 30 μm or less, and the matrix glass is contained in an amount of 5 mass % or less. The zirconia-mullite refractory raw material has a chemical composition comprising 30 to 55 mass % of ZrO | 11-25-2010 |
20100219212 | UPPER NOZZLE - The present invention is directed to creating a less-energy loss or smooth (constant) molten steel flow with a focus on a configuration of a bore of an upper nozzle, so as to provide an upper nozzle formed with a bore having a configuration capable of to suppress deposit formation. For this purpose, in an upper nozzle | 09-02-2010 |
20100200619 | SLIDING NOZZLE DEVICE AND PLATE USED FOR THE DEVICE - It is intended to develop a technique of pressing and fixing a plate by a uniform force to suppress the occurrence of a crack around a nozzle hole of the plate during use, and provide a sliding nozzle device capable of improving durability of the plate, and a plate for use in the sliding nozzle device. The sliding nozzle device comprises a plate ( | 08-12-2010 |
20100163586 | STOPPER STRUCTURE AND PRODUCTION METHOD THEREFOR - The present invention provides a stopper structure capable of preventing loosening of a shaft rod during use, and gas leakage which is likely to occur when the stopper structure is designed to allow gas to pass therethrough. The shaft rod | 07-01-2010 |
20100119441 | Reactive working material for use in hydrogen production by decomposition of water - Disclosed is a reactive working material for use in a process of producing hydrogen by splitting water based on a two-step thermochemical water-splitting cycle through the utilization of solar heat, industrial waste heat or the like, which comprises a ferrite fine powder and a cubic zirconia supporting the ferrite fine powder. This reactive working material makes it possible to prevent scaling off of the ferrite fine powder from the zirconia fine powder due to volumetric changes of the ferrite fine powder during repeated use, and suppress growth of FeO grains due to repetition of melting and solidification when used as a reactive working material for a cyclic reaction under a high temperature of 1400° C. or more. | 05-13-2010 |
20100092750 | HIGH-DURABILITY SLEEVE BRICKS - Disclosed is a magnesia-carbon based sleeve brick for steelmaking converters, which is obtained by adding, to a refractory raw material mix containing 60 to 95 mass % of a magnesia raw material and 5 to 20 mass % of graphite, a metal powder of one or more selected from the group consisting of Al, Si, Mg, Ca, Cr and an alloy thereof, in an amount of greater than 3 to 6 mass %, and an organic binder, in addition to 100 mass % of the refractory raw material mix, and subjecting the resulting mixture to kneading, forming and heat treatment, wherein the sleeve brick is used under a condition that a thickness thereof is set at 70 mm or less. This makes it possible to prevent cracking which would otherwise occur in the sleeve brick itself, to allow the sleeve brick to have enhanced durability. One or more selected from the group consisting of B, B | 04-15-2010 |
20100084441 | REFRACTORY MATERIAL FOR NOZZLE FOR USE IN CONTINUOUS CASTING, AND CONTINUOUS CASTING NOZZLE - In a insert-type continuous casting nozzle comprising a highly functional layer formed to have a high corrosion resistance, a high anti-attachment capability, etc., and provided to define an inner bore thereof, the present invention is directed to providing a refractory material (mortar) for an intermediate layer of the continuous casting nozzle, which has a property capable of fixing an inner bore-side layer to an outer periphery-side layer (a nozzle body) of the continuous casting nozzle, while preventing the occurrence of expansion splitting in the outer periphery-side layer due to a difference in thermal expansion between the inner bore-side and outer periphery-side layers, and a continuous casting nozzle using the refractory material for the intermediate layer. The refractory material for the intermediate layer contains a hollow refractory aggregate in an amount of 10 to 75 volume %, wherein a ratio of an average radius R of each particle of the aggregate to an average wall thickness t of the particle satisfies the following relation: R/t≧10. This refractory material is disposed between an inner bore-side layer ( | 04-08-2010 |
20090096124 | Method of producing anti-alumina-buildup immersion nozzle for continuous casting - A method of producing an immersion nozzle for continuous casting, which includes integrally molding a first zirconia-graphite compound applied to a powder-line portion of the nozzle, and a second compound applied to at least an inner hole portion of the nozzle. The second compound includes 10 mass % or more of clinker particles each containing CaO as a mineral phase, and the surface of at least a part of the clinker particles is subjected to an anti-hydration treatment, such as a heat treatment to be performed under a CO | 04-16-2009 |