Abstract: A method and an apparatus for the rapid melting of glasses in a skull crucible is provided. The method and apparatus introduce high-frequency energy into the contents of the crucible by means of a coil arrangement surrounding the skull crucible, in order to heat the melt, and the batch is laid and the molten glass discharged in the upper region of the crucible, and undissolved constituents of the batch are retained by means of a cooled bridge which is immersed in the melt. The glass is taken off above the coil arrangement and is fed for further processing without flowing through the coil region.

Abstract: A glassmelting furnace is heated by combustion of fuel having an atomic ratio of hydrogen to carbon of 0.9 or less.

Abstract: Certain preferred embodiments of the present invention provide a system for and method of analyzing and cleaning a cullet stream prior to bottle manufacturing. In accordance with certain aspects of the present invention, the system includes a raw materials feeder, a mixing stage, a melting stage, a bottle-forming stage, a cooling/annealing stage, an inspection stage, and a batch controller. The raw materials feeder further includes a cullet bin within which is cullet supply, a feeder, an analysis device, and removal assembly. Certain preferred embodiments of the method include the steps of feeding cullet onto the conveyor, performing real-time composition analysis of the cullet, removing contaminants from the cullet, determining whether the cullet batch is consistent with a predetermined tolerance threshold, adjusting the glass batch formulation, sending the batch ingredients to the mixing stage, and then completing the overall glass manufacturing process.

Abstract: A method of manufacturing glass melt and a method of manufacturing molded glass material by forming glass melt. In the method of manufacturing glass melt, the glass melt containing fluorine is prepared by melting glass raw materials and refining the resulting glass melt. The refining is conducted in a refining vat equipped with a flow inlet through which flows glass melt obtained by heating and melting the glass raw materials, and a flow outlet through which flows glass melt that has been refined, with the level of the glass melt being maintained in such a manner that the flow inlet and flow outlet remain beneath the surface of the glass melt and the glass melt does not contact external air. The method of manufacturing a molded glass material comprises the step of molding the glass melt produced by the above method.

Abstract: A conduit for molten glass, a molten glass degassing method and a sub-atmospheric apparatus are provided, which are able to produce homogenous and good quality glass at low cost. A conduit for molten glass, which is capable of flowing molten glass in a horizontal direction, and to which vertical pipes are connectable, is disposed in a substantially horizontal direction. The conduit for molten glass can increase the area of a free surface of the molten glass by setting a width W at a larger value than a height H in cross-section and having an outline in cross-section comprising a convex curve. When the conduit for molten glass thus configured is used as a sub-atmospheric apparatus, it is possible to degas the molten glass effectively. Additionally, it is possible to have a sufficient strength since the convex curve forming the cross-section is elliptical. Further, it is possible to reduce costs by decreasing the amount of metal required for forming the cross-section.

Abstract: The invention relates to an apparatus and a method for low-contamination melting of high-purity, aggressive and/or high-melting glass or glass-ceramic. According to the invention, for this purpose a melt is heated in a crucible or melting skull crucible by means of high-frequency radiation and is mixed or homogenized in the melting crucible. It is preferable for a gas nozzle, from which gas bubbles, e.g. oxygen bubbles (known as O2 bubbling), escape into the melt, to be provided at the base of the crucible. This alone makes it possible to achieve surprising multiple benefits in the melting skull crucible. Firstly, unmelted batch which drops into the melt in solid form, for example from above, is melted down more quickly as a result of more intensive mixing with the liquid fraction of the melt, secondly the temperature distribution in the melt is made more even, thirdly a uniform distribution or mixing of different glass constituents is achieved, and fourthly the redox state of the glass can be adjusted.

Abstract: A method of controlling reaction paths of glass batch components added to a resident glass melt is provided, including the steps of providing a plurality of raw material batch components according to a batch recipe, selectively combining a portion of the batch components into a first combination material having a melting temperature in a range of 60 to 90% of a resident melt temperature (K) and a viscosity3 a melt viscosity/100, and selectively combining another portion of the batch components into a second combination material having a reaction temperature in a range of 60 to 100% of the resident melt temperature, the second combination material being capable of forming an intermediate compound via a solid state reaction before reacting with the glass melt. The first and second combination materials and any remaining batch components are mixed and introduced into a glass melter.

Abstract: A glass with high internal transmission as well as low tendency to radiation-caused physical compaction and low tendency to solarization, comprising 18 to 31% by weight of SiO2, 0 to 7% by weight of Na2O3, 0 to 7% by weight of K2O, 65 to 84% by weight of PbO, 0.001 to 1% by weight of As2O3+As2O5, which is characterized by a content of 0 to 5000 ppm of Sb2O3 0 to 500 ppm of TiO2 0 to 100 ppm of CuO 0 to 1000 ppm of F. The ?(As2O3, As2O5, Sb2O3, F)?20 ppm and the ratio of As(III)/As(V) is at least 0.5. Such a glass is suitable for the use as optical element.

Abstract: A glass melting furnace has a gas inlet positioned proximate to a charging section oxy-fuel combustion region to introduce gas into the region and to at least partially displace gas having a partial pressure of alkali vapor from the region, and optionally a gas outlet is adapted to provide an exit for a volume of furnace atmosphere. A method for reducing alkali vapor corrosion of glass furnace refractory structures includes providing a gas inlet proximate to the oxy-fuel combustion region; introducing a volume of gas from the inlet into the region, displacing a volume of gas having a partial pressure of alkali vapor from the region; and, optionally providing a gas outlet adapted to provide an exit for a volume of furnace atmosphere.

Abstract: The process of the invention produces alkali-free aluminosilicate glass having an Al2O3-content of more than 12% by weight with the addition of from 0.005% by weight to 0.6% by weight of sulfate for batch formulation.

Abstract: A method and device for nozzle-injection of gas into molten glass is disclosed wherein a gas stream is introduced into the molten glass in a temporally pulsed throughput such that the gas stream is interrupted between two sequential pulses, the duration of each pulse amounting to less than one second.

Abstract: The invention relates to a process for the production of a glass melt. For the avoidance of the oxygen reboil the process is equipped with the following process stages or steps: a melting stage a refining stage a homogenizing and conditioning stage; in which before the homogenizing and conditioning stage the melt is heated to a temperature of over 1700° C.; in which polyvalent ions are present in the melt in a proportion of at least 0.5% by wt.

Abstract: A method and system for feeding and burning pulverized fuel, such as petroleum coke, in a glass melting furnace, which includes a glass melting and a plurality of burners associated with a pair of sealed regenerative chambers disposed side-by-side which act as heat exchangers, the burners are arranged in a series of ports that are associated with the glass melting region of the furnace. The system includes means for supplying the pulverized fuel by each one of the burners for melting glass raw materials. The emissions of flue gases produced by the combustion process of the fuel in the furnace are controlled in order to maintain clean the flue gases and for reducing the emission of impurities from the fuel such as SOx, NOx and particulates.

Abstract: A method of producing flat glass in which foam which appears on the surface of molten glass melted using oxy-fuel burners is dispersed by directing a diffuse, luminescent flame onto the surface of the glass carrying the foam.

Abstract: The process of the invention produces alkali-free aluminosilicate glass having an Al2O3-content of more than 12% by weight with the addition of from 0.005% by weight to 0.6% by weight of sulfate for batch formulation.

Abstract: A method of making glass (e.g., grey in color in some embodiments, or otherwise colored in other embodiments) in a manner so as to reduce selenium (Se) burnoff. In some embodiments, Epsom salt(s) is added to the glass batch in order to reduce Se burnoff. The resulting glass product is useful, for example, in vehicle and/or architectural privacy glass applications.

Abstract: In many engineering production processes, for example glass or glass-ceramic manufacturing processes, liquids, such as glass melts, participate in the processes in which gases are dissolved, which in part form bubbles in the liquid. So that the quality of the final product is not disadvantageously influenced, the liquid, e.g. glass melt, should be refined to remove the bubbles. According to the method of the invention an overpressure acting on the liquid is provided which is such that the internal pressure in the bubbles immediately under the surface of the liquid in a refining chamber is at least as great as the sum of equilibrium pressures of the gases dissolved in the liquid and the sum of the vapor pressure of components evaporating from the liquid. A two stage apparatus is provided which performs a preferred embodiment of the refining method of the invention.

Abstract: An alkali-free glass applicable to a light transparent glass substrate in a liquid crystal display essentially consists, by weight, of basic elements of 40-70% SiO2, 6-25% Al2O3, 5-20% B2O3, 0-10% MgO, 0-15% CaO, 0-30% BaO, 0-10% SrO, and 0-10% ZnO, and a fining agent of a combination of 0.05-3% Sb2O3 and at least one of 0.05-2% SnO2 and 0.005-1% Cl2, which fining agent makes the resultant glass free from bubbles without the use of toxic As2O3 which has been known as the fining agent in the art.

Abstract: The invention concerns an optical colored glass of the composition (in % in weight on oxide basis) SiO2 50-62; K2O 10-25; Na2O 0-14; Al2O3 0-2; B2O3 3-5; ZnO 13.5-37; F 0-1; TiO2 0-7; In2O30-2; Ga2O3 0-2; SO30-1; SeO20-1; C 0-1; MIMIIIY2II 0.1-3, whereby MI=Cu+ and/or Ag+ and/or MIII=In3+ and/or Ga3+ and/or Al3+ and/or YII═S2− and/or Se2− and at least 0.1% in weight of the oxide (M2O3) of the MIII, which is/are present in MIMIIIYII2, and with at least 0.2% in weight of the oxide, of the YII, which is/are present in MIMIIIYII2.

Abstract: An alkali-free glass applicable to a light transparent glass substrate in a liquid crystal display essentially consists, by weight, of basic elements of 40-70% SiO2, 6-25% Al2O3, 5-20% B2O3, 0-10% MgO, 0-15% CaO, 0-30% BaO, 0-10% SrO, and 0-10% ZnO, and a fining agent of a combination of 0.05-3% Sb2O3 and at least one of 0.05-2% SnO2 and 0.005-1% Cl2, which fining agent makes the resultant glass free from bubbles without the use of toxic As2O3 which has been known as the fining agent in the art.

Abstract: Glass is produced in a glassmelting furnace by combusting fuel and oxidant having an oxygen content greater than 80 vol. % oxygen in a melting zone to form molten glass, wherein the surface of the molten glass is exposed to the gaseous atmosphere in the melting zone and the water vapor content of the atmosphere at the surface of the molten glass is greater than 35 vol. %, and oxidant having an oxygen content greater than 80 vol. % is injected into the refining zone of the furnace under conditions to minimize mixing of said oxidant with gases above said oxidant and sweep water vapor at the surface of the molten glass into the melting zone to lower the water vapor content of the atmosphere at the surface of the molten glass.

Abstract: An alkali-free glass applicable to a light transparent glass substrate in a liquid crystal display essentially consists, by weight, of basic elements of 40-70% SiO2, 6-25% Al2O3, 5-20% B2O3, 0-10% MgO, 0-15% CaO, 0-30% BaO, 0-10% SrO, and 0-10% ZnO, and a fining agent of a combination of 0.05-3% Sb2O3 and at least one of 0.05-2% SnO2 and 0.005-1% Cl2, which fining agent makes the resultant glass free from bubbles without the use of toxic As2O3 which has been known as the fining agent in the art.

Abstract: A method is provided for the production of glass with reduced volatilization of components. Such method allows the reduction of emitted metals and other volatiles in the production of glass. The method encompasses the use of a calcium magnesium silicate in the production glass composition.

Abstract: Glass raw material is fed to a glass furnace to prepare molten glass. At least one metal compound from one of the following metals: aluminum, titanium, silicon, zinc, magnesium, iron, chromium, cobalt, cerium or calcium is supplied to a foam layer formed on the molten glass to diminish or extinguish the foam layer.

Abstract: In many engineering production processes, for example glass or glass-ceramic manufacturing processes, liquids, such as glass melts, participate in the processes in which gases are dissolved, which in part form bubbles in the liquid. So that the quality of the final product is not disadvantageously influenced, the liquid, e.g. glass melt, should be refined to remove the bubbles. According to the method of the invention an overpressure acting on the liquid is provided which is such that the internal pressure in the bubbles immediately under the surface of the liquid in a refining chamber is at least as great as the sum of equilibrium pressures of the gases dissolved in the liquid and the sum of the vapor pressure of components evaporating from the liquid. A two stage apparatus is provided which performs a preferred embodiment of the refining method of the invention.

Abstract: In many engineering production processes, for example glass or glass-ceramic manufacturing processes, liquids, such as glass melts, participate in the processes in which gases are dissolved, which in part form bubbles in the liquid. So that the quality of the final product is not disadvantageously influenced, the liquid, e.g. glass melt, should be refined to remove the bubbles. According to the method of the invention an overpressure acting on the liquid is provided which is such that the internal pressure in the bubbles immediately under the surface of the liquid in a refining chamber is at least as great as the sum of equilibrium pressures of the gases dissolved in the liquid and the sum of the vapor pressure of components evaporating from the liquid. A two stage apparatus is provided which performs a preferred embodiment of the refining method of the invention.

Abstract: The invention relates to lead-free optical glasses having a refractive index nd of from 1.52 to 1.58, an Abbe number vd of from 50 to 57 and a negative partial dispersion &Dgr;Pg,F of <−0.0090, having a composition (in % by weight, based on oxide) of SiO2>15-25; B2O3 45-55; Al2O3 8-13; CaO 2-8; ZnO 0-5; with CaO+ZnO 2-10; Li2O 0-4; Na2O 0-4; K2O 0-4; with Li2O+Na2O+K2O 3-8; La2O3 0-14; Nb2O5 0-4.8; Ta2O5>10-17; with Ta2O5+Nb2O5>10-17; SnO2 0-2; ZrO2 0-7; with Ta2O5+ZrO2>10-<18.

Abstract: A system for melting and delivering glass to a work area such as spinners for making fiberglass includes a melter with heaters so arranged that the “hot spot” in the molten glass is located away from the walls and corrosion sensitive parts so that the various elements of the melter wear out at substantially the same time. The system is further provided with a dual exhaust arrangement when the melter, conditioner and forehearth are located on the same floor of the plant, the first exhaust being at the juncture of the melter and conditioner, and the second being an alternating replacement for one of the heating/cooling orifices and mechanisms in the conditioner, so as to effectively limit the amount of corrosive volatiles reaching the forehearth.

Abstract: The invention relates to a process for the production of a glass melt.

Abstract: In an industrial glass furnace, which optionally contains recuperators, regenerators, electric boost or other devices for providing heat to glass batch material, at least one staged combustion oxy-fuel burner is mounted in the roof of the furnace to provide heat to melt the glass batch material by providing a flow of fuel to the oxy-fuel burner; providing a flow of gaseous oxidant in association with said the oxy-fuel burner; injecting the fuel and the oxidant into the furnace; and, combusting the fuel such that at least a portion of combustion is effected in the vicinity of said glass forming material to enhance convective and radiative transfer of heat to said glass forming material without substantially disturbing the glass forming material. In one embodiment, the oxy-fuel burner is adapted for injecting liquid fuels.

Abstract: A system for melting and delivering glass to a work area such as spinners for making fiberglass includes a melter with heaters so arranged that the “hot spot” in the molten glass is located away from the walls and corrosion sensitive parts so that the various elements of the melter wear out at substantially the same time. The system is further provided with a dual exhaust arrangement when the melter, conditioner and forehearth are located on the same floor of the plant, the first exhaust being at the juncture of the melter and conditioner, and the second being an alternating replacement for one of the heating/cooling orifices and mechanisms in the conditioner, so as to effectively limit the amount of corrosive volatiles reaching the forehearth.

Abstract: The present invention relates to a process and apparatus to cast and form slag directly from the molten state into crystalline or amorphous products suitable for use as decorative and structural building and construction materials. Molten slag and additives are refined at high temperature in a treatment furnace for a period of hours. The eventual entrapped gas content is controlled using a variety of methods, such as vacuum pressures and bottom stirring with inert gas. The molten slag is cast directly into moulds, and these moulds form the slag into any shape desired. The formed products are immediately introduced into a heat treatment furnace at temperatures at or above the glass transition temperature (GTT) for the case of crystalline products, or just below the GTT for amorphous products. The product is thermally cycled over a period of hours to relieve thermal stresses during cooling to ambient temperatures.

Abstract: A bushing tip plate support assembly for a bushing in a filament forming apparatus is disclosed. The support assembly improves the flatness of the tip section within the spans between the external support and the center support. The filament forming apparatus includes a bushing having a bottom plate from which nozzles or tips depend. The disclosed support assembly is an improvement on the internal support assemblies in conventional bushings because it has several functions. The support assembly includes two vertical dividers mounted in the bushing. The bottom ends of the dividers are welded to the tops of tip plate gussets in the bushing. The dividers are attached to side plates of the bushing as well. An upper portion of each divider serves as an upper side wall for the bushing and defines part of the throat of the bushing into which the molten glass flows. The dividers also include middle and lower portions with perforations through which the glass in the bushing may flow.

Abstract: Briefly, according to the present invention there is provided a refractory lined glass melter for producing refined glass from raw glass-forming material using at least one oxygen-fuel burner recessed within a burner block mounted in the roof of the furnace and a process of using the burner. The velocities of the gaseous fuel and of the oxygen from the oxygen-fuel burner are controlled such that the velocities of the gaseous fuel and the oxygen are substantially equivalent to provide a generally laminar gaseous fuel and oxygen flow to combust proximate a top surface of the raw glass-forming material and produce a flame which impinges the surface of the raw glass-forming material and which has a middle portion of a columnar shape.

Abstract: An apatite glass ceramic is described which is characterized by good chemical stability, a low expansion coefficient and high translucence, and is particularly suitable, by itself or together with glasses or other glass ceramics, as a veneering material for ceramic dental restorations.