Abstract: A forehearth (1) or working-end for glass furnace of the type including one or more modules or sections (2), each one having: —an understructure (3) in which a vat (4) is defined into which the molten glass flows; —a superstructure (5) including a cooling air duct (13) and a pair of lateral fume ducts (20), communicating with the vat area (4) into which the molten glass flows, characterised in that, next to an outlet opening (17) of the duct (13), a “Venturi block” (22) is provided, into which both the cooling air from the duct (13) and the fumes from the fume ducts (20) flow, shaped in such a way that the cooling exit air causes the fumes to be extracted from the fume ducts (20). The forehearth and the fume extraction procedure enable the thermal homogeneity of the glass to be improved while reducing the use of refractory material, the formation of cracks in the superstructure and costs.

Abstract: A chamber (101, 201), for holding molten glass (113, 202) having a free surface (114, 203), includes a bellows (4, 204), a sealing ring (10, 210), and a cover (30, 50, 230). The bellows is coupled to the chamber, and the sealing ring is coupled to the bellows. The sealing ring may include one or more various devices, associated with operation of the chamber, including: an atmosphere supply tube (14, 214), an electric lead (12), a pressure differential sensor (16, 216), a thermo couple, an oxygen sensor, and/or an auxiliary port (18). The sealing ring further includes an upper opening (21) having an inner diameter (22). The cover is removably coupled to the sealing ring and extends over the sealing-ring-upper-opening inner diameter, wherein the sealing ring is disposed between the cover and the chamber. The cover may include various separately removable sections (30, 32, 34, 35, 37, 50, 52, 54).

Abstract: The present invention relates to a glass meting furnace comprising a channel-shaped melting tank, the batch materials being introduced at an upstream end, the molten glass being recovered at the downstream end, said furnace being heated by means of burners, in which the combustion energy is produced by oxy-fuel combustion in respect of at least 65% thereof, the burners being distributed on the walls along the length of the furnace, in which flue gas discharge is mostly localized close to the upstream end near the openings through which the batch materials are introduced, the rest of the flue gas being removed close to the downstream part so as to maintain dynamic sealing with respect to the surrounding atmosphere.

Abstract: A vacuum degassing apparatus having a throughput of at least 200 tons/day without causing problems such as a stagnation of molten glass flow in the molten glass flow path, an increment of flow rate of the molten glass flow in a local area, an excessive increment of pressure loss of the molten glass flow. A vacuum degassing apparatus comprises a vacuum degassing vessel, and an uprising pipe and a downfalling pipe which are connected with the vacuum degassing vessel, wherein the vacuum degassing vessel includes a wide portion for providing a molten glass flow path, and in the wide portion, the proportion W1/L1 of the breadth of molten glass flow path W1 to the length of molten glass flow path L1 is at least 0.

Abstract: The present invention provides a vacuum degassing apparatus and a vacuum degassing method for molten glass, which can suppress generation of bubbles on an interface between molten glass and a wall face of a conduit for molten glass such as a vacuum degassing vessel, an uprising pipe or a downfalling pipe that constitute a vacuum degassing apparatus, or influence of lowering of vacuum degassing effect due to rise of the level of molten glass in the vacuum degassing vessel, and which can stably exhibit the effect of vacuum degassing.

Abstract: Methods and apparatus for controlling glass flow in, for example, a downdraw glass manufacturing process (e.g., the fusion downdraw process) are provided. In certain aspects, the mass, thickness, and/or the temperature distribution of molten glass (40) on the surface of forming apparatus (60) is managed by: (A) constructing a stream-tube mapping between (i) regions (510; FIG. 5A) of a cross-section of a conduit (400) that supplies molten glass (40) to the forming apparatus (60) and (ii) regions (510; FIG. 5B) on the exterior surface of the forming apparatus (60); (B) using the stream-tube mapping to select a temperature distribution for the cross-section that results in a desired mass, thickness, and/or temperature distribution of molten glass (40) on the surface of the forming apparatus (60); and (C) heating and/or insulating the conduit (400) so as to produce a temperature distribution for the cross-section which equals or at least approximates the distribution selected in step (B).

Abstract: The present invention is directed toward a method of reducing contamination of a glass melt by oxide particulates, such as particulates of platinum oxide, which may condense on the inside surfaces of a stir chamber, particularly the stir shaft, and fall back into the glass melt. The method includes causing a flow of gas through an annular space between the shaft and the chamber cover. In one embodiment, the flow of gas through the annular space is caused by drawing a vacuum in the chamber. An apparatus for practicing the method is also provided.

Abstract: A method for the refining of glass by means of high temperatures in a skull crucible is provided. The method includes introducing a glass melt in the skull crucible through an inlet disposed at an upper region of the skull crucible, heating the skull crucible by irradiation of high-frequency energy, and discharging the glass melt from the skull crucible through an outlet disposed at the upper region, the outlet being disposed at a place essentially lying opposite the inlet.

Abstract: A vacuum degassing apparatus for molten glass includes a vacuum housing which is evacuated to be depressurized therein; a vacuum degassing vessel which is provided in the vacuum housing to vacuum-degas molten glass as the molten glass flows therein; an uprising pipe which connects to the vacuum degassing vessel, and sucks and draws up undegassed molten glass to introduce the undegassed molten glass into the vacuum degassing vessel; and a downfalling pipe which connects to the vacuum degassing vessel and draws down the degassed molten glass from the vacuum degassing vessel to discharge the degassed molten glass. The cross sectional area of the path at the upper end portion of the uprising pipe is larger than the cross sectional area of the path at the lower end portion of the uprising pipe.

Abstract: Feed materials are melted in a furnace to form a glass melt in a first vessel, transferred through a first refractory metal connecting tube to a second vessel for conditioning, then transferred through a second refractory metal connecting tube to a third vessel where the glass melt is fined. A gas is bubbled into the glass melt through an injection tube disposed in the first connecting tube, optionally in the second connecting tube, and optionally in both connecting tubes. The gas may be used to mix the melt and/or recharge a fining agent with oxygen.

Abstract: A process for melting and refining vitrifiable materials, such that all or part of the thermal energy necessary for melting the said vitrifiable materials is supplied by the combustion of fossil fuel(s) with at least one oxidizer gas, the fuel(s)/gas or the gaseous products resulting from the combustion being injected below the level of the mass of vitrifiable materials (7). The refining of the vitrifiable materials after melting comprises at least one step of subjecting them to subatmospheric pressure while centrifuging.

Abstract: A glass melting apparatus is provided with a clarifier tank adapted to clarify melted glass which is obtained by melting a raw glass material. Partition walls are provided in the clarifier tank so as to define a meandering flow passage through which the melted glass flows. A bottom of the clarifier tank is sloped so that the flow passage ascends from an upstream side thereof to a downstream side thereof.

Abstract: A conduit structure for molten glass, a conduit system for molten glass, a vacuum degassing apparatus and a method for vacuum-degassing molten glass by use of the vacuum degassing apparatus, which are capable of effectively removing components eluted from a refractory brick forming a conduit for molten glass, foreign substances generated in the interface between molten glass and a platinum wall surface forming a conduit for molten glass, a bubble remaining in a surface layer of molten glass, a glass material denatured by volatilization, and the like, are provided.

Abstract: A front end for a glass forming operation comprises an open channel and at least one burner. The channel has at least one surface. The surface has at least one hole therein. The burner is oriented in the hole at an acute angle relative to the surface. In another embodiment of the invention, the channel has a top and a pair of sidewalls each having a surface. At least one hole is in at least one of the surfaces. The hole is at an acute angle relative to at least one surface. The burner is an oxygen-fired burner. In yet another embodiment of the invention, the top and sidewalls each have a super structure surface constructed of refractory material. The channel has an upstream end and a downstream end. At least one of the surfaces has a plurality of holes therein. The burners extend at an acute angle relative to at least one surface and in a plane extending between the upstream end and the downstream end and perpendicular to at least one surface. Oxygen-fired burners extend axially through corresponding holes.

Abstract: A charged glass raw material B is melted in a melting tank 10 by heating with a burner 31 and by heating with electrodes 12, to form molten glass G. Then, the molten glass G flows into a tank additionally provided as a noble gas dissolving tank 20 through a throat 40. The noble gas dissolving tank 20 is provided with a noble gas dissolving device 53, and the noble gas dissolving device 53 is provided with sixteen noble gas inlets 22 for introducing a helium or neon gas supplied to a hearth through heat resistant gas introduction tubes 21 into the noble gas dissolving tank 20. Bubbles of a helium gas A having a purity of 99% are blown out from the noble gas inlets 22 in volumes such that the bubbles have an average diameter of 80 mm or less in the molten glass G.

Abstract: In some embodiments, the invention provides a refining chamber for glass production, made of platinum group metal materials, with improved refining effectiveness. The refining chamber according has the shape of a tube with a cross section (1), with the cross section of the tube being shaped, in at least one segment, so that in the operating position the length (10) of a horizontal line (12) which divides the surface of the cross section into essentially a lower and an upper segment of the surface, both of which have essentially the same area, is greater than twice the maximum vertical extent (30) of the lower segment of the surface. The cross section of the refining chamber can, for example, have the shape of an oval, an ellipse, a slot, a rounded triangle or a polygon, and the stiffness of the shape of the refining chamber can be increased by forming radially peripheral creases, corners, waves or folds.

Abstract: A glass-melting furnace (10) has an upstream end (6), a downstream end (8), and a roof (22). The upstream end is positioned upstream of the downstream end. A charger (32) is provided to supply glass-forming material (30) to the upstream end of the furnace. At least one burner (34) is provided to supply heat to the glass-forming material at the upstream end of the furnace. An exhaust (60) is in communication with the downstream end of the furnace, with the exhaust being positioned downstream of the at least one burner.

Abstract: A front end for a glass forming operation including an open channel and at least one burner. The channel surface has at least one burner port and a burner oriented in the burner port at an acute angle relative to the channel surface. The surface may be a top, side or end wall and the burner port is at an acute angle relative to the surface of the wall.

Abstract: Forehearths that create a substantially homogeneous temperature to molten glass forming materials across the end position are provided. A gas cavity, a weir, a refractory block, or a heating element in the forehearth may be utilized to reduce a temperature gradient of molten glass forming materials across the end position. Reducing the temperature difference of the molten glass forming material across the end position permits for improved chemical and physical properties of the glass fibers and the end products formed from the glass fibers. In addition, a reduction in the temperature gradient across the end position produces a more homogenous glass fiber and glass product. Further, a reduction in the shear break rate occurs when the molten glass forming material has a temperature that is substantially the same across the end position, which results in a reduction in the breakage of glass fibers and an increase in manufacturing efficiency.

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 apparatus for reduced-pressure refining of a glass melt includes a refining bank formed so that a reduced pressure is generated by a glass flow in it. The refining bank has a component, which is made from a refractory metal or refractory alloy acting as glass-contact material. The refractory metal or alloy contains molybdenum, tungsten, tantalum, and/or hafnium. The device of the present invention includes a protective gas reservoir for a protective gas and an automatically operating valve connecting the reservoir with the refining bank so that an inner side of the component that would otherwise be exposed when a pressure rise or a falling glass melt column occurs is protected from oxidation by the protective gas. A process for using the device during refining of the glass melt is also part of the invention.

Abstract: The basic shape of the molten glass fining apparatus of the present invention is preferably either an elliptical or a somewhat rectangular shape such that the flow is more uniform and the bubbles have less distance to rise to the surface. A novel baffle design is also shown. The present invention improves the fining capability of the apparatus without increasing the cost of construction materials. In fact, the cost may be reduced.

Abstract: A method and system feed and burn pulverized fuel, such as petroleum coke, in a glass melting furnace having burners associated with sealed regenerative chambers which act as heat exchangers. The system supplies the pulverized fuel 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. The regenerative chambers are manufactured with selected refractories such as magnesium, zircon-silica-alumina, or magnesia and zirconium-silicate, for counteracting the erosive and corrosive effects produced by the combustion process of the fuel in the glass melting chamber. A burner feeds the petroleum coke and simultaneously mixes a primary air and pulverized fuel-air mixture for the burning of the pulverized fuel.

Abstract: A method for controlling the foam produced when a molten material encounters reduced pressure in a vacuum chamber includes passing the molten material through an aging zone in the vacuum chamber in which the molten material is allowed to drain from between the bubbles of the foam and then collapsing the bubbles of the drained foam.

Abstract: Methods of manufacturing glass sheets with manufacturing systems that including platinum-containing components are provided. The method includes providing a barrier coating to reduce the hydrogen permeability of the platinum-containing components which reduces the propensity for blistering of glass sheets made using the components.

Abstract: The double-walled noble metal duct (1) for conducting a glass melt has an outer noble metal pipe (1b) and an inner noble metal pipe (1a) extending within the outer pipe, so that an inner space (21) is formed within the inner pipe and an intermediate space (23) is formed between the inner pipe (1a) and the outer pipe (1b). The intermediate space is completely filled with glass melt when the double-walled noble metal duct conducts the glass melt, when the outer pipe (1b) has an exhaust vent (4). The outer pipe (1b) also has a bottom outlet (7) communicating with the intermediate space for removal of oxygen bubbles formed on the outer wall. The noble metal duct can be used in glass conditioning and in the manufacture of glass articles that are devoid of polyvalent ions.

Abstract: A vacuum degassing apparatus for molten glass includes a vacuum housing; a vacuum degassing vessel provided in the vacuum housing; an uprising pipe which connects to the vacuum degassing vessel; and a downfalling pipe which connects to the vacuum degassing vessel. The vacuum housing has an accommodating portion to accommodate the uprising pipe and an accommodating portion to accommodate the downfalling pipe, at least one of which is divided horizontally into a plurality of sections to form a plurality of divided rooms juxtaposed in the vertical direction, and the respective divided rooms are provided with a pressure controller to control the pressures of the respective divided rooms independently.

Abstract: The invention relates to a skull pot (1) for melting, crystallizing or refining inorganic substances. Said pot comprises a pot wall (1.1), a pot bottom (1.2), an induction coil (2) which surrounds the pot wall (1.1) and by means of which high-frequency energy can be coupled into the content of the pot. The pot wall (1.1) is formed by a ring of metal pipes which can be connected to a cooling medium. Slits are embodied between adjacent metal pipes. The bottom (1.2) is provided with a discharge for the melt (3). A sleeve (4) is allocated to the discharge. The admission end (4.1) of the sleeve (4) protrudes far into the inner chamber of the skull pot (1) in such a way that, during use, the melt (3) can be withdrawn through the crystallized bottom layer (3.3) in a controlled manner without the danger of impairing quality.

Abstract: This invention relates to a device for melting or refining glass or glass ceramics. According to the invention, such a device is provided with the following characteristics: a channel which is arranged in an essentially horizontal manner and which is provided with an inlet and an outlet for the glass melt; and an HF coil for coupling HF energy into the melt is allocated to the channel. The channel is made of a plurality of metal pipes in a similar way to a skull pot. Said pipes can be connected to a cooling medium.

Abstract: The invention relates to a skull pot for melting or refining glass or glass ceramics, comprising a pot wall (1), a pot base, and an induction coil (3) which surrounds said pot wall and through which high-frequency energy can be coupled into the contents of the pot. The pot wall is made up of a ring of metal pipes (1.1) which can be connected to a cooling medium, slot-type intermediate chambers being provided between adjacent metal pipes. The pot base has a run-off for the melt. The metal pipes (1.1) that form the pot wall (1) arm short-circuited with each other above the base in order to increase the degree of efficiency of the skull pot and especially, in order to even out the temperature profile of the melt throughout the depth of the melt.

Abstract: The subject of the invention is a process for melting and refining vitrifiable materials, such that all or part of the thermal energy necessary for melting the said vitrifiable materials is supplied by the combustion of fossil fuel(s) with at least one oxidizer gas, the said fuel(s)/gas or the gaseous products resulting from the combustion being injected below the level of the mass of vitrifiable materials (7). The refining of the vitrifiable materials after melting comprises at least one step of subjecting them to subatmospheric pressure.

Abstract: An apparatus for making glass in which a glass melt is refined in a vessel with oxygen is described. It includes a melt-containing vessel (10) having a refining region (3) for refinement of the glass melt and a noble metal member for producing oxygen in the melt. The noble metal member (40) has an outer side facing the glass melt and an inner side facing away from the glass melt washed with and acted on with oxygen. Oxygen-containing bubbles are vigorously generated on the outer side of the noble metal member facing the glass melt when the inner side is washed with the oxygen.

Abstract: The present invention is to provide an all-electric glass-melting deep furnace and a method of refining and supplying glass in which high-quality molten glass can be efficiently produced in large quantity at high heat efficiency. An all-electric glass-melting deep furnace 20 has a bottom 2 and a side wall 4 constructed by piling up fireproof bricks 3 on the perimeter of the bottom 2. A height H of the side wall 4 is set to be twice or more than twice as long as an inside dimension D of the bottom 2 of the furnace. Since the furnace 20 is deep, there can be achieved a thick batch layer, a space in which glass is melted at high temperature, and a cooling area which is necessary to refine molten glass. The method of the present invention makes it possible to remove seeds which are generated when glass raw material are melted.

Abstract: A method for equalizing temperature differences in molten glass in at least one temperature equalization zone that is in the form of a channel for transporting a glass melt. The equalization zone is located upstream from a tapping point, at which the glass is tapped into a mold in a forming machine, or the like. Resistor heating elements are provided in the temperature equalization zone side walls, bottom wall, and roof. The temperatures of the surfaces of the respective side walls, bottom wall, and roof that are in contact with the resistor heating elements are measured. The resistor heating elements are controlled by an electric controller so that the temperatures of the surfaces are substantially equal to a predetermined tapping temperature of the glass melt.

Abstract: A molten glass supply device is provided, which can solve unavoidable problems for high viscosity characteristics in connection with the conventional molten glass supply device for high viscosity glass. Such problems include improperly high heating cost caused by excessive heat radiation in a melting furnace, reduction in the grade of products deriving from an excess amount of an erosion foreign material and reduction in the product yield. High viscosity molten glass having a property in which a temperature at which the molten glass exhibits a viscosity of 1000 poise is 1350° C. or higher is supplied to a forming device through a melting furnace, a distribution portion in communication with the outlet of the melting furnace, and a plurality of branch paths branching from the distribution portion. In the branch paths, distribution resistance providing portions that provide distribution resistance to molten glass passed through the branch paths are provided.

Abstract: The basic shape of the molten glass fining apparatus of the present invention is preferably either an elliptical or a somewhat rectangular shape such that the flow is more uniform and the bubbles have less distance to rise to the surface. A novel baffle design is also shown. The present invention improves the fining capability of the apparatus without increasing the cost of construction materials. In fact, the cost may be reduced.

Abstract: The invention relates to a method for producing and/or preparing molten glass. The invention is characterised by the following: the molten glass flows in a container in a principal flow direction, the level of the molten glass being at a specific height above the base surface of the container; streams of a free-flowing medium are introduced into the molten glass in such way that said glass flows in spiral paths and that the axes of the spirals run parallel or approximately parallel to the principal flow direction; neighbouring inlet points of the streams are separated by a mutual distance, (viewed from the principal flow direction), of at least 0.5 times the height of the molten glass level.

Abstract: The invention relates to a device for melting or refining glass or glass ceramics. According to the invention, a device of this type is provided with the following characteristics: a plurality of tubes which are U-shaped and arrange side by side so that they form a cage like skull channel that is open on top, and a high frequency oscillation circuit which comprises an induction coil. The tubes can be connected to a cooling medium. The induction coil wraps around the channel in such a manner that winding sections extend along the lateral walls of the channel.

Abstract: The invention concerns NOx-reduced firing of glass melting furnaces with preferably lateral fuel introduction at the combustion air ports thereof, wherein cross-flows of combustion air and combustible gas are suppressed by means of wall segments arranged in the combustion air port, air turbulence at the wall segment is reduced by waste gas filling of reduced-pressure regions and a primarily low-turbulence flame base is produced, which is based on the introduction of combustible gas in the form of a free jet. The wall segment and the waste gas filling jointly form a so-called flame base screen. As a secondary aspect the free jet is protected by the combustible gas jet being introduced into the core shadow of the flame base screen. The wall segment preferably simulates the idealised projection of a free gas jet, from the direction of view of the afflux flow of combustion air.

Abstract: The invention relates to a melting cistern for producing a glass melt as well as to its refining,

Abstract: The subject of the invention is a process for melting and refining vitrifiable materials, such that all or part of the thermal energy necessary for melting the said vitrifiable materials is supplied by the combustion of fossil fuel(s) with at least one oxidizer gas, the said fuel(s)/gas or the gaseous products resulting from the combustion being injected below the level of the mass of vitrifiable materials (7). The refining of the vitrifiable materials after melting comprises at least one step of subjecting them to subatmospheric pressure. The invention also relates to the device for implementing the process and to its applications.

Abstract: A glass feeder comprises an enclosed chamber through which molten glass can pass, and passing through each side wall into the chamber at least one burner comprising first and second burner head means for combusting oxidant and fuel within said chamber so as to generate flames which extend in axially opposite directions along each side wall, adjacent and parallel to the side walls and adjacent the surface of the molten glass.

Abstract: The invention relates to a method and a device for refining a glass melt according to the skull pot principle. According to the invention, the inlet and outlet are located in the upper area of the crucible and lie diametrically opposite each other.

Abstract: The apparatus for refining a glass melt has a refining unit, which includes a horizontally extending refining section for removal of rising gas bubbles from the glass melt flowing through the refining section. So that the refining section can be shortened in contrast to a refining section in an apparatus with an open channel flow, the refining section according to the invention is formed so that the glass melt flow rate is higher over a substantial lengthwise portion of it near its bottom and lower near a surface of the glass melt flowing through it in comparison to the corresponding flow rates in an open channel flow for the same throughput. The refining section is advantageously at least partially covered with a fire resistant cover, which contacts the glass melt flowing through it and has at least one opening through which gas bubbles can escape. In addition the refining section may be provided with built-in elements shaped to provide the desired improved flow rate profile for the glass melt.

Abstract: A front end for a glass forming operation comprises an open channel and at least one burner. The channel has at least one surface. The surface has at least one hole therein. The burner is oriented in the hole at an acute angle relative to the surface. In another embodiment of the invention, the channel has a top and a pair of sidewalls each having a surface. At least one hole is in at least one of the surfaces. The hole is at an acute angle relative to at least one surface. The burner is an oxygen-fired burner. In yet another embodiment of the invention, the top and sidewalls each have a super structure surface constructed of refractory material. The channel has an upstream end and a downstream end. At least one of the surfaces has a plurality of holes therein. The burners extend at an acute angle relative to at least one surface and in a plane extending between the upstream end and the downstream end and perpendicular to at least one surface. Oxygen-fired burners extend axially through corresponding holes.

Abstract: A device and method for the plaining of glasses or glass-ceramics. The device is provided with a melting vat, at least two plaining containers serially connected after the outlet of the melting vat, and at least one of the plaining containers is built in accordance with the skull principle from a plurality of metal tubes comprising a cooling agent connection and a high-frequency device for inductively coupling high-frequency energy into the contents of the plaining container.

Abstract: Molten glass has a liquid level located at a higher level than lower ends of an uprising pipe and a downfalling. In addition, a contacting portion of the uprising pipe or the downfalling pipe and a brick receiver on an upstream or downstream pit for supporting the uprising or downfalling pipe, or a joint in the brick receiver is filled with sealing material.

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: The double-walled noble metal duct (1) for conducting a glass melt has an outer noble metal pipe (1b) and an inner noble metal pipe (1a) extending within the outer pipe, so that an inner space (21) is formed within the inner pipe and an intermediate space (23) is formed between the inner pipe (1a) and the outer pipe (1b). The intermediate space is completely filled with glass melt when the double-walled noble metal duct conducts the glass melt when the outer pipe (1b) has an exhaust vent (4). The outer pipe (1b) also has a bottom outlet (7) communicating with the intermediate space for removal of oxygen bubbles formed on the outer wall. The noble metal duct can be used in glass conditioning and in the manufacture of glass articles that have polyvalent ion vacancies.

Abstract: The invention relates to a device for purifying molten glass;