Abstract: The invention relates to a furnace having an inner wall, an outer wall and a heat insulation arranged in between. The heat insulation is foamed up in situ, and hardened, from a mass which contains,per 100 parts by weight of a reactive solid (stone-forming component),40-250 parts by weight of a water-containing hardener which effects the hardening reaction of the reactive solid (stone-forming component) in the alkaline region,40-250 parts by weight of fillers and a blowing agent.The reactive solid used is preferably a reactive solid from the group comprisingI finely dispersed oxide mixture containing amorphous silica and alumina,II a glassy, amorphous electrostatic precipitator ash,III ground calcined bauxite,IV electrostatic precipitator ash from lignite-fired power stations,V undissolved, amorphous SiO.sub.2, especially from an amorphous, disperse-pulverulent, dehydrated or water-containing silica or from high-temperature processes (silica fume), andVI metakaolin.

Abstract: A mold for forming an open top, walled member having side walls and a bottom surface for containing a molten metal. The mold including an inner screen having a plurality of openings having inner side walls and a bottom surface. The mold further includes an outer wall, wherein the inner screen and the outer wall are spaced relative to each other to define a space so that the side walls and the bottom surface of the open top, walled member are formed therebetween.

Abstract: Molten salt process for destruction of fluorine-containing waste in a molten salt such as molten sodium carbonate, and forming fluoride salts in the molten salt bath. The destructive phase change of conventional alpha-alumina refractory of the molten salt retaining vessel in the presence of such fluoride salts is avoided according to the invention by employing phase change resistant beta-alumina refractory bricks.

Abstract: Renovation of a heating wall, in particular a heating wall head of a coke oven battery, includes starting with reconstruction of the wall to be renovated on a wall protective plate of the part, abutting a new masonry exactly on the wall protective plate, and arranging between the new masonry and the old masonry a vertically extending welding joint for sealing the ceramic welding after heating up the new masonry, which means after reaching final thermal expansion of the new masonry.

Abstract: A process for cleaning a surface of a refractory structure which is at an elevated temperature, including projecting against the surface a comburent gas stream which is a powder stream including fuel particles carried in an oxygen-containing carrier gas the comburent gas stream impinging upon the surface at an impingement zone, whereby the fuel particles are caused or allowed to burn in a reaction zone defined generally around the impingement zone and the heat generated by the combustion of the fuel particles causes the surface or material adhered thereto to melt and provide a melted material, and projecting a scouring stream including oxygen simultaneously or alternately at the surface to scour the surface in the vicinity of the reaction zone and thereby clean the surface due to the scouring stream blowing away the melted material.

Abstract: A continuous checker column is molded and formed in situ inside a regenerative chamber, thereby eliminating the need for large numbers of individual, preformed checker bricks. A plurality of rigid molding rods or flexible cable rods are passed through, or hang from, a template installed in or above the empty checker chamber portion of a regenerative chamber. The molding rods are sized, shaped, and spaced to correspond substantially to the size, shape and spacing of the openings desired in the checker column. Then, a refractory material is injected into the checker column and allowed to harden. The molding rods are at least partially retracted, leaving the desired openings in the hardened refractory material. The injection and retraction steps can be repeated, as necessary, until the entire checker column has been formed.

Abstract: A pelletizable gunning composition is provided which exhibits excellent flow characteristics, minimal release of dust, and excellent adhesion and resistance to slag. The gunning composition includes high density magnesium oxide as the primary component, and lesser quantities of powdered metal, refractory clay, binder and, preferably, graphite. The dry components are mixed together, and the binder is added and mixed, resulting in a composition that can be pelletized. After pelletizing, the composition can be coated with a dusting material to facilitate pellet flow and prevent pellet agglomeration.

Abstract: A projecting construction apparatus for a molten-metal-discharging hole includes a rotating shaft and an impeller rotatably supported by the end of the rotating shaft. The impeller has vanes radially disposed and is open to fluid flow in a generally axial direction, such that gas flowing axially toward the impeller can pass substantially axially through the impeller without being deflected against a wall of the hole, while liquid and solid material are deflected by the vanes against the wall of the hole. At least two material-supplying pipes are located around the rotating shaft, and are connected to supply projection material entrained in a fluid to the impeller, and have ejection ports generally equi-angularly disposed about the shaft axis. The ejection ports are directed toward the vanes, and a plurality of control valves are connected to respective ones of the pipes so as to control an amount of the projection material which is supplied to each of the pipes.

Abstract: A method of applying a hot composite on top of the refractory lining of steel making and processing vessels is disclosed. The composite may be applied to the refractory wall in more than one layer, including a dense intermediate layer for adhesion, and a less dense layer on top that is designed to be consumed as a slag-forming component during steel making and refining. The composite is applied by discharging a carrier gas containing a mixture of small particles, including particles of silica, particles of at least one high-temperature oxide based material and particles of solid carbonaceous fuel, through a carrier gas discharge nozzle. Additional substances may be added to the mixture to enhance the slag-forming process. A controllable flow of oxidizing gas is charged at high and preferably supersonic speed through an essentially crescent-shaped nozzle partially surrounding the carrier gas discharge nozzle.

Abstract: The invention concerns a ceramic welding process in which a mixture of refractory and fuel particles is projected from an outlet at an end of a lance in a gas stream against a target surface where the fuel particles combust in a reaction zone to produce heat to soften or melt the projected refractory particles and thereby form a coherent refractory weld mass. A method of monitoring the distance between the lance outlet and the reaction zone is disclosed in which the reaction zone and at least part of the gap between that reaction zone and the lance outlet is monitored by a camera and an electronic signal is produced indicative of the distance ("the working distance") between the lance outlet and the reaction zone.

Abstract: In the construction of a hot blast stove, walls are made of pre-formed and baked bricks. At the joint between two walls, cast joining elements of complex shape are incorporated. The cast joining elements may be cast in situ. This avoids the need for pressing joining bricks of a variety of shapes.

Abstract: An expendable lining may be applied over the interior walls of a metal handling vessel for molten metal, e.g. a tundish. The expendable lining is usually applied over a relatively permanent, e.g. refractory brick, lining.If the expendable lining is formed by placing a suitable former inside the vessel to define a space corresponding to the desired lining, filling the space with particulate refractory material and heating, it has been found difficult to provide adequately uniform heating and to avoid distortion of the former.

Abstract: Method for lining a distributor for the continuous casting of metals, in particular steel, comprising preparing material for constituting a wear-resistant refractory lining of the distributor with raw natural dolomite, or raw natural calcite, or a mixture of these two materials, which are chosen with a particle size of between 0 and 5 mm, incorporating in this raw material a binder in proportions of 0.4 to 5% by weight and a mineral or organic plasticizer in proportions of 0.2 to 3% by weight and, after the lining has been placed in position on the distributor in the aqueous form, proceeding to the decarbonation of this lining in the course of its drying and baking, characterized in that the method further comprises incorporating in the material of the lining at least one compound having the property of shrinking at temperatures lower than about 700.degree. C.

Abstract: The invention relates to a metallurgical vessel, in particular a transport ladle or a treating ladle, for the production of steel with a bottom (2b) having a refractory lining (3) with a basic working layer (5). In order to create a durable lining it is provided that the working layer (5) consists at least in part of dry basic bulk material, the upper side of which is covered, before the vessel (1) is heated for the first time, by a chemically hardened protective layer (6) and which, after the vessel (1) has been filled, is partly present as a monolithic layer or the upper side of the working layer (5) is covered, before the vessel (1) is charged for the first time, by a monolithically fritted basic layer formed by heating the bulk material. The invention furthermore relates to a method of making the refractory linings of such vessels.

Abstract: A process for renewing the refractory lining of a ladle for casting steel and of similar metallurgical vessels. While the ladle (10) is still hot, the slag (S) still adhering to the inner surface (26) is melted off from the remaining lining (2) with the aid of a high-temperature burner (9) operating under reducing conditions and allowed to run out of the ladle (10) in the molten condition. After cooling, the glassy surface of the remaining lining (2) is roughened. The new refractory lining (30) is then applied by casting, with the aid of a template.

Abstract: A method for increasing the durability of refractory linings in vessels having inclined areas or conical parts in their inside contour includes in fitting the refractory bricks obliquely following the inside contour of the vessel. The slant of the bricks is brought about step by step by several layers of machine-pressable turning bricks of known uniform density. This method makes it possible to obtain softer transitions from the horizontally laid bricks to the obliquely laid bricks.

Abstract: An impeller as used in a projecting construction apparatus for a concave section of a molten-metal-discharging hole is supported on a rotating shaft for redirecting flow of impinging projection material. The impeller includes a plurality of vanes which are attached to the rotating shaft with a specified twisting angle relative to the rotating shaft. A material supplying pipe is directed upon the plurality of vanes, so that, upon impingement of the projection material upon the plurality of vanes, the projection material is projected outwardly and in a direction nearly opposite to the predetermined direction of impingement of the projection material supplied through the material-supplying pipe.

Abstract: In ceramic welding processes, oxidising gas and a mixture of refractory and fuel powders are projected against a surface and the fuel is burnt to generate sufficient heat that the refractory powder becomes at least partially melted or softened and a cohesive refractory mass is progressively built up against that surface. In order to reduce any tendency for the weld mass to include a low-grade refractory phase and thus promote the refractoriness of that weld mass, the fuel powder is present in a proportion of not more than 15% by weight of the total mixture and includes at least two metals selected from aluminium, magnesium, chromium and zirconium, and in that at least the major part by weight of the refractory powder consists of one or more of magnesia, alumina and chromic oxide, and in that the molar proportions of silica and calcium oxide present in the refractory powder (if any) satisfy the following expression: molar concentration of SiO.sub.2 in % .ltoreq.0.

Abstract: A reconstruction of a heating wall of a coking oven. The reconstruction includes utilization of a novel large size cast refractory repair module which may be utilized to replace existing silica bricks within a coke oven heating wall. The novel large size cast refractory module are monolithic structures formed from a castable refractory material having very high dimensional stability over a wide range of temperatures. Each repair module is a rectangular parallelepiped having one or more vertically extending flues formed therein, one end of a module being adapted to conform to the end shape of the damaged heating wall, the other end of the module being adapted to interfit with existing brickwork. The modules are assembled by initially removing damaged brickwork from the heating wall and then placing in the new modules which are mortared in place.

Abstract: A method for repairing a hot-blast, long-time cupola furnace by removing residual slag and relining the cupola furnace including feeding liquid nitrogen to the cupola furnace immediately at the end of a smelting operation and simultaneously with the feeding of the liquid nitrogen, removing residual slag from the furnace. The furnace is cooled with liquid nitrogen until the furnace reaches a temperature of less than or equal to 40.degree. C. after which the furnace is relined with fresh refractory tamping compound.

Abstract: Apparatus for repairing a refractory body, such as a furnace wall by projecting combustible particles in an oxygen-rich carrier gas against such body to cause oxidation of combustible particles in a reaction zone adjacent such body and thereby the generation of heat required for dressing such body or forming a refractory weld mass thereon, wherein the combustible particles are introduced into a first gas and oxygen-rich gas is forced through an entrainment zone 6 in which it produces an aspirating effect whereby a flow of combustible particles and first gas is induced into the entrainment zone 6 and the induced flow of combustible particles and first gas is carried along a conduit 9 and a lance 21 with the oxygen-rich gas to the reaction zone.

Abstract: The device mounted at the end of an operating arm comprises one or more suckers for supporting objects, for example refractory bricks for the brick-lining of a metallurgical converter, means for linear and angular displacement of the suckers, sensors for monitoring and controlling automatically the means of displacement in order to grip and position the objects in a predetermined location, after immobilization of the operating arm. The suckers are provided on a sucker-carrying plate which in its turn is supported by a pair of blocks which can slide in transverse slide bars of a carriage which comprises a pair of longitudinal slide bars, perpendicular to the transverse slide bars and housed in sliding fashion in a central support attached to the end of the operating arm with a degree of angular freedom and a degree of linear freedom orthogonal to the axes of the longitudinal and transverse slide bars.

Abstract: A metallurgical vessel (1) whose inner walls to be lined are relatively hot is placed on a suitable support; the support is tilted and the metallurgical vessel (1) is brought successively into a number of different positions, in each of which an inner wall or a part of wall of the vessel is substantially horizontal and turned upwards; in each of the abovementioned positions at least one layer of a substantially dry material comprising a mixture of refractory particles and a binder of the thermosetting or equivalent type is spread on the inner wall or part of wall, the composition and the particle size range of the mixture of refractory particles being such that this mixture sinters in contact with the liquid metal, and this material is spread out so as to form a substantially uniform layer, the inner walls of the vessel being initially at a sufficient temperature to be able to heat the material deposited on them to a temperature permitting the softening and the setting of the binder of thermosetting or equiva

Abstract: A refractory coating composition, adapted to be applied to a substrate by spraying or gunning, comprising:from about 25 to about 40% by weight alumina;from about 15 to about 25% by weight ceramic fiber;from about 40 to about 60% by weight colloidal silica; andsufficient water to form an aqueous suspension thereof.

Abstract: A method of repairing an eroded refractory wall pierced by one or more openings using a ceramic welding technique. A member of shape substantially complementary to the desired shape of the repaired opening is placed into each opening so that the member projects from the refractory wall by an extent at least equal to the local depth of erosion. Such complementarily-shaped member is so composed that it is adapted to withstand ceramic welding temperatures. A desired refractory repair mass is built up, by ceramic welding, adherent to the eroded wall and surrounding the complementarily-shaped members(s) while leaving its end or their ends exposed, and the complementarily-shaped member(s) is or are thereafter removed from the repaired openings(s). Such complementarily-shaped member may, for example, be of refractory carbon or of steel, such as stainless steel. Such a steel member may be tubular for the circulation of coolant.

Abstract: In a process for intermittently spraying a setting pasty composition mixed with a tempering liquid, in particular for building up refractory linings of metallurgical vessels, the composition is conveyed from a preparing station (6) at which it is prepared, to a delivery nozzle (11). In order to prevent the composition from thickening or hardening in the duct (15) leading to the delivery nozzle (11) when delivery is interrupted, it is conveyed during delivery stops in a circuit that includes the delivery nozzle (11).

Abstract: A process of repairing a refractory body, including the steps of a. introducing combustible particles into a first gas stream containing no more than 18% oxygen by volume; b. causing an oxygen-rich gas stream to flow through a particle entrainment zone into a reaction zone adjacent a refractory body to be repaired so as to produce an aspirating effect within the particle entrainment zone effective to induce a flow of the first gas stream containing the combustible particles into the particle entrainment zone and through to the reaction zone; and c. projecting the combustible particles entrained in the oxygen-rich gas stream against the refractory body to cause oxidation of the combustible particles in the reaction zone adjacent the refractory body and generate sufficient heat for one of dressing the refractory body or forming a refractory weld mass thereon.

Abstract: A method of hot repair heating trains of a coke oven battery includes brick laying of a heating train, warming a finished portion of a respective heating train during the brick laying to a temperature of approximately 250.degree. C., directly after ending the brick laying heating a new heating train to a temperature of approximately 500.degree. C., performing the warming and heating by means of gaseous heat carrier, blowing the heat carrier into the heating trains and heating the heat carrier in a heat exchange with use of heat of hot parts of the coke oven battery.

Abstract: Binder-impregnated carbon fiber rovings and the like, which are sticky and difficult to handle, are stacked to form modules that are packed in resinous bags under vacuum, and are then shaped to desired dimensions and densities without employing conventional molds, but simply by placing them in the confines of jigs or ruler frames and then releasing them from vacuum and expanding them to the desired dimensions. They are thereafter subjected to heat treatments to provide high temperature resistant carbon fiber-reinforced carbon or graphite modules which work, for example, as thermal insulation and refractory walls in high temperature heating furnaces.

Abstract: Disclosed is a non-inflammable insulating, composite material capable of being shooted onto a surface to be coated, such as the wall of a building to be insulated. This material comprises a fibrous-like, synthetic forsterite obtained by calcination of chrysolite asbestos fibers at a temperature from 650.degree. to 1450.degree. C.; an inorganic, lightweight filler selected amongst vermiculite, perlite and their mixtures; and a non-inflammable, hydraulic or silicate binder contained in such an amount as to make the material sufficiently adhesive to be shooted as a coating, either as such or after wetting, onto the surface to be insulated. The weight ratio of the synthetic forsterite to the inorganic filler is ranging from 20:80 to 80:20 to adjust the volumic weight of the final product from about 0.20 to about 0.50 gram per cm3. Also disclosed are methods of manufacturing such a non inflammable, insulating, composite material in a wet, ready-to-be-shooted form.

Abstract: A method of making an insulating furnace lining by forming a reticulated ceramic having interconnected webs defining a plurality of interconnected pores and a plurality of fibers distributed within substantially all of the pores in a selected volume of the reticulated ceramic. The reticulated ceramic is arranged to form at least a portion of a furnace lining. The reticulated ceramic and the fibers may be oxides, ceramics, carbides, nitrides, silicides, borides, carbon and mixtures thereof. The fibers form a batt which fills at least a portion of the pores.

Abstract: A device for repairing a hole in an object, including a flexible backing member which can be bent and positioned through a hole, of smaller diameter than the backing member, in order to support and position a fluent patching material. A rigid front dam is then positioned on the front of the hole and attached to the backing member using a connecting member. Front dam may have an impressionable material on one of its sides so that a desired texture can be impressed, and cast on the front of the hole repair.

Abstract: An improved apparatus and method of the inline degassing of the molten metal employing a fluxing gas.

Abstract: A method of flame spraying refractory material for in situ repair of, e.g., furnace linings wherein an inert carrier gas incapable of supporting combustion and particles of refractory oxide and combustible metal or other oxidizable material are delivered to a flame spraying apparatus wherein high pressure oxygen aspirates and accelerates the carrier gas-particle mixture; a controlled ratio of 5 to 1 to about 30 to 1 oxygen gas to carrier gas; allows for the use of highly combustible metals and materials such as chromium, aluminum, zirconium, and/or magnesium as heat sources without back-flash and at a deposition rate in excess of 2000 pounds per hour of refractory oxide to yield a deposited refractory mass exhibiting enhanced wear and erosion resistance.

Abstract: A particulate composition suitable for use in a process of dressing a refractory structure which includes the steps of projecting against a site of refractory structure to be dressed a comburent gas stream carrying a mixture comprised of fuel particles and refractory oxide particles, which fuel particles are comprised of at least one element which is oxidisable to form at least one refractory oxide; and causing or allowing the fuel particles to burn, the particulate composition being a mixture including fuel particles comprised of at least one element which is oxidisable to form a refractory oxide; refractory oxide particles; and particles of fluxing agent the fluxing action of which is such that when the mixture is projected in a comburent gas stream and the fuel particles are caused or allowed to burn, the refractory structure becomes softened to an extent such that the refractory structure becomes dressed by removal or displacement of material thereof under the mechanical action of the impinging comburent

Abstract: A ceramic fiber containing refractory moldable composition suitable for use with molten aluminum alloys, the composition comprised of 10-18 wt. % ceramic fiber, 33-45 wt. % colloidal silica, 30-42 wt. % total content of liquid carrier, 0.2-2.5 wt. % organic polymer and 1-15 wt. % barium sulfate. The composition has a high level of resistance to attack or penetration by molten aluminum.

Abstract: A tap spout, particularly for allowing molten metal to be discharged from oxygen-steel converters, includes a replaceable unit including a tubular wear lining and a jointing layer secured thereto. An inner lining of the tap spout may thus be repaired with relatively simple maintenance work by removing the inner lining and subsequently inserting the replaceable unit into an outer lining of the tap spout to form a new inner lining of the tap spout. The replaceable unit is adapted to facilitate either a press fit, and in particular, a fit ensured by axial compression of the jointing layer, or an expansion fit with the outer lining to secure the replaceable unit therein.

Abstract: A method of increasing the life of tuyere area refractories through repeated application of coherent refractory mass formed by ceramic welding process onto worn area after installing protective removable, expendable or reuseable pipes/rods. Consecutive use of this process can effectively suspend or reduce or control the wear of the original refractories.

Abstract: The present invention was developed to solve the problems inherent in conventional dry type and wet type gunning methods. The main point of the present invention is a novel method for gunning a refractory composition for obtaining a lining body having high density and high strength by premixing a refractory composition with water amounting to 1/5-3/4 of the total amount of water for the lining, and subsequently adding and mixing the rest of the water at the inside of the gunning nozzle of the dry gunning equipment while gunning.

Abstract: A process and an apparatus, by means of which the used surface of the lining of a steel ladle can be worked away, following the contours, in uniform layer thickness. On compliantly displaceable arms, tools are pressed against the inner circumference of the lining which exert a hammering pact against the surface layer of the lining under the effect of a vibrator. Then a mold is lowered into the ladle and the space remaining between the mold and the worked-away inner surface is filled with a pourable, refractory material, which bonds with the old lining to form a new monolithic lining.

Abstract: A refractory furnace (10) is constructed to facilitate repair of worn or damaged refractory portions while the furnace is maintained at near-operating temperature. A sidewall (40) of the refractory furnace is comprised of a plurality of modular sections (85) each of which includes a refractory lining (87). One or more modular sections may be selectively replaced when becoming worn or damaged. Replacement is accomplished by external access and removal of the worn or damaged modular sections.

Abstract: An apparatus which is adapted to move along a tundish, ladle, or the like having a generally closed lower end, enclosed sides, and an open upper end. The apparatus sprays the sides and lower end of the tundish with refractory material. The apparatus comprises a nozzle having an inlet and an outlet, and a base movable in an x direction generally horizontally along the tundish, a boom movable in a vertical y direction, a lance movable in a z direction generally perpendicular to the x and y directions, and a rotatably swivel bracket for rotating the nozzle outlet about an axis extending in the y direction. The apparatus also includes piping for supplying fluidized refractory material to the nozzle inlet, and a water ring for wetting the fluidized material before the nozzle outlet.

Abstract: A mixture of powdered metals and oxides used in ceramic welding for repairing fire brick linings of industrial ovens by blowing the powdered mix on hot oven walls in a stream of oxygen, where the powders have the characteristics providing for initial ignition of the stream of particles in the flame zone before they strike the oven wall and the oxidation continues after the particles form refractory mass on the oven wall.

Abstract: A refractory heat-insulating graphite sheet material characterized in that the material comprises a graphite sheet.

Abstract: A new method of making an electrically conductive hearth in a d.c. furnace is effected by first heating bricks such as magnesite-graphite bricks and the like, from their new commercially available form to high temperatures decresing the normal resistivity of the bricks and thereafter laying the bricks to form the hearth from top to bottom with the heat treated bricks.

Abstract: A modified metallurgical converter wherein removable segments or portions are provided in the anticipated areas of highest wear of its refractory lining, and methods for repairing same. Also, a method for improving the service and operational life of such metallurgical converters.

Abstract: A refractory product is shown in the form of a dense sintered alumina-chromia, zirconia-alumina-silica, zirconia-alumina body, or zirconia-chromia-alumina having less than about 8% of homogeneously distributed closed porosity formed by sintering an intimate interdispersion of fine particles of alumina-chromia, zirconia-alumina-silica, zirconia-alumina, or zirconia-chromia-alumina.

Abstract: A process for reducing the cracking tendency and improving the strength of specified rammed plastic refractory reactor liners is described, the process comprising heating reactor liner mounted in a reactor, prior to its first use, to a temperature of from about 490.degree. C. to about 510.degree. C., the heating being carried out by heating said liner at a rate to produce a temperature increase of the liner not greater than about 6.degree. C. per hour. A reactor comprising a vessel or tube having a liner of the type specified and cured in the manner described is also disclosed.

Abstract: An internal lining for protecting the permanent refractory lining of a metallurgical vessel (1, 2) such as a tundish, casting ladle or slag pot has a base of refractory inorganic particles coated with a binder. The protective internal lining is constituted by at least two layers, namely an inner layer (3) which sinters throughout its mass under the action of heat of the molten metal contained in the metallurgical vessel, and a layer (4 or 5) which does not sinter at all or sinters only to a partial extent in order to remain friable even when the inner layer (3) has completely sintered.

Abstract: A process of forming a refractory mass on a surface, which process includes spraying against that surface a mixture of refractory particles and oxidisable particles which react exothermically with oxygen to generate sufficient heat to soften or melt at least the surfaces of the refractory particles and so bring about formation of said refractory mass, and causing the sprayed mixture to be heated sufficiently to cause the oxidisable particles to undergo such exothermic reaction, the granulometry of the particles which are sprayed in the mixture being such that the mean of the 80% and 20% grain sizes of the refractory particles is greater than the mean of the 80% and 20% grain sizes of the oxidisable particles and that the size range spread factor of the refractory particles is at least 1.2.