Abstract: Repositionable heater assemblies and methods of controlling temperature of glass in production lines using the repositionable heater assemblies are disclosed. The repositionable heater assembly includes a support frame, a first sled and a second sled each coupled to the support frame with bearing members that allow the first sled and the second sled to translate in a longitudinal direction. Each of the first sled and the second sled include at least one heating element, where the heating elements are spaced apart from the glass ribbon a spacing distance. The first and second sleds are movable in the longitudinal direction to controlling the spacing distance between the heating elements of the first sled and the second sled and the glass ribbon to manage temperature of the glass ribbon.

Abstract: A method of forming a glass article includes drawing a glass ribbon from a draw housing in a downstream direction, heating portions of only a bead of the glass ribbon to form compressive stress regions in the bead, scoring the glass ribbon to form a score line on which the glass ribbon is broken. The bead is heated at a position upstream from the score line. An apparatus for manufacturing a glass article includes a draw housing for forming a glass ribbon having a bead, a heating apparatus with a heat source for forming compressive stress regions in portions of only the bead of the glass ribbon, and a scoring apparatus that forms a score line on which the glass ribbon is broken to form the glass article. The heat source moves downstream simultaneously with the glass ribbon.

Abstract: A glass manufacturing apparatus is described herein that comprises a forming device configured to produce a glass ribbon and a pull roll device which draws the glass ribbon downward from the forming device. The pull roll device has a first roll apparatus, a second roll apparatus, and a third roll apparatus. The pull roll device is configured to at least independently operate the first roll apparatus and the second roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: A glass manufacturing apparatus comprises a forming device configured to produce a glass ribbon and a control device configured to independently operate a first pull roll apparatus and a second pull roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: A method for making a glass laminate sheet including: selecting a core glass composition and a clad glass composition combination for a glass laminate structure; determining and comparing the viscosity and coefficient of thermal expansion (CTE) profiles for each of the selected core and the clad glass compositions with each other over a temperature range of interest including the onset of viscoelasticity to ambient temperature; and processing the selected core and clad glass composition in a laminate fusion draw apparatus to form a laminate glass sheet in accordance with at least one difference condition for the clad effective coefficient thermal expansion (CTEeff core) and the core effective coefficient thermal expansion (CTEeff core). Another method for making a glass laminate sheet includes controlling the cooling rate to control the resulting strength of the laminate.

Abstract: Methods and apparatuses for fabricating continuous glass ribbons are disclosed. The method includes forming the continuous glass ribbon by drawing the continuous glass ribbon from a draw housing in a drawing direction, heating at least one portion of a central region of the continuous glass ribbon at a heating location downstream of the draw housing, sensing a temperature of the continuous glass ribbon at a sensed temperature location downstream of the draw housing, and automatically controlling the heating of the at least one portion of the central region of the continuous glass ribbon based on the sensed temperature to mitigate distortion of the continuous glass ribbon.

Abstract: A glass manufacturing apparatus comprises a forming device configured to produce a glass ribbon and a control device configured to independently operate a first pull roll apparatus and a second pull roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: A method of forming a glass article includes drawing a glass ribbon from a draw housing in a downstream direction, heating portions of only a bead of the glass ribbon to form compressive stress regions in the bead, scoring the glass ribbon to form a score line on which the glass ribbon is broken. The bead is heated at a position upstream from the score line. An apparatus for manufacturing a glass article includes a draw housing for forming a glass ribbon having a bead, a heating apparatus with a heat source for forming compressive stress regions in portions of only the bead of the glass ribbon, and a scoring apparatus that forms a score line on which the glass ribbon is broken to form the glass article. The heat source moves downstream simultaneously with the glass ribbon.

Abstract: Repositionable heater assemblies and methods of controlling temperature of glass in production lines using the repositionable heater assemblies are disclosed. The repositionable heater assembly includes a support frame, a first sled and a second sled each coupled to the support frame with bearing members that allow the first sled and the second sled to translate in a longitudinal direction. Each of the first sled and the second sled include at least one heating element, where the heating elements are spaced apart from the glass ribbon a spacing distance. The first and second sleds are movable in the longitudinal direction to controlling the spacing distance between the heating elements of the first sled and the second sled and the glass ribbon to manage temperature of the glass ribbon.

Abstract: Repositionable heater assemblies and methods of controlling temperature of glass in production lines using the repositionable heater assemblies are disclosed. The repositionable heater assembly includes a support frame, a first sled and a second sled each coupled to the support frame with bearing members that allow the first sled and the second sled to translate in a longitudinal direction. Each of the first sled and the second sled include at least one heating element, where the heating elements are spaced apart from the glass ribbon a spacing distance. The first and second sleds are movable in the longitudinal direction to controlling the spacing distance between the heating elements of the first sled and the second sled and the glass ribbon to manage temperature of the glass ribbon.

Abstract: A method for making a glass laminate sheet including: selecting a core glass composition and a clad glass composition combination for a glass laminate structure; determining and comparing the viscosity and coefficient of thermal expansion (CTE) profiles for each of the selected core and the clad glass compositions with each other over a temperature range of interest including the onset of viscoelasticity to ambient temperature; and processing the selected core and clad glass composition in a laminate fusion draw apparatus to form a laminate glass sheet in accordance with at least one difference condition for the clad effective coefficient thermal expansion (CTEeff core) and the core effective coefficient thermal expansion (CTEeff core). Another method for making a glass laminate sheet includes controlling the cooling rate to control the resulting strength of the laminate.

Abstract: A glass manufacturing apparatus comprises a forming device configured to produce a glass ribbon and a control device configured to independently operate a first pull roll apparatus, a second pull roll apparatus, and a third pull roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque, at least one of a first midstream pair of draw rolls rotates with a substantially constant torque, and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: Repositionable heater assemblies and methods of controlling temperature of glass in production lines using the repositionable heater assemblies are disclosed. The repositionable heater assembly includes a support frame, a first sled and a second sled each coupled to the support frame with bearing members that allow the first sled and the second sled to translate in a longitudinal direction. Each of the first sled and the second sled include at least one heating element, where the heating elements are spaced apart from the glass ribbon a spacing distance. The first and second sleds are movable in the longitudinal direction to controlling the spacing distance between the heating elements of the first sled and the second sled and the glass ribbon to manage temperature of the glass ribbon.

Abstract: A flange (13) for use in direct resistance heating of a glass-carrying vessel (10), such as a finer, is provided. The flange comprises a plurality of electrically-conductive rings which include an innermost ring (140) which is joined to the vessel's exterior wall (12) during use of the flange and an outermost ring (150) which receives electrical current during use of the flange. The innermost ring (140) comprises a high-temperature metal which comprises at least 80% platinum and the outermost ring (150) comprises at least 99.0% nickel. This combination of materials both increases the reliability of the flange and reduces its cost. In certain embodiments, the flange can also include one or more rings (190) composed of a platinum-nickel alloy which has a lower thermal conductivity than platinum or nickel and thus can serve to reduce heat loss through the flange.

Abstract: Methods and apparatuses for fabricating continuous glass ribbons are disclosed. The method includes forming the continuous glass ribbon by drawing the continuous glass ribbon from a draw housing in a drawing direction, heating at least one portion of a central region of the continuous glass ribbon at a heating location downstream of the draw housing, sensing a temperature of the continuous glass ribbon at a sensed temperature location downstream of the draw housing, and automatically controlling the heating of the at least one portion of the central region of the continuous glass ribbon based on the sensed temperature to mitigate distortion of the continuous glass ribbon.

Abstract: Methods for controlling thickness variations across the width of a glass ribbon (104) are provided. The methods employ a set of thermal elements (106) for locally controlling the temperature of the ribbon (104). The operating values for the thermal elements (106) are selected using an iterative procedure in which thickness variations measured during a given iteration are employed in a mathematical procedure which selects the operating values for the next iteration. In practice, the method can bring thickness variations of glass sheets within commercial specifications in just a few iterations, e.g., 2-4 iterations.

Abstract: A glass manufacturing apparatus is described herein that comprises a forming device configured to produce a glass ribbon and a pull roll device which draws the glass ribbon downward from the forming device. The pull roll device has a first roll apparatus, a second roll apparatus, and a third roll apparatus. The pull roll device is configured to at least independently operate the first roll apparatus and the second roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: A glass manufacturing apparatus comprises a forming device configured to produce a glass ribbon and a control device configured to independently operate a first pull roll apparatus and a second pull roll apparatus such that at least one of a first upstream pair of draw rolls rotates with a substantially constant torque and at least one of a first downstream pair of draw rolls rotates with a substantially constant angular velocity. In further examples, methods of manufacturing a glass ribbon are provided.

Abstract: Methods and apparatus for controlling the stress in, and the shape of, the glass ribbon (15) formed in a downdraw glass manufacturing process (e.g., the fusion downdraw process) are provided. In certain embodiments, the control is achieved by cooling the bead portions (21a, 21b) of the ribbon (15) at a rate which provides a heat flux Q?b at the thickest part of the bead (23a, 23b) which is given by Q?b=Q?q+?Q?, where (i) Q?q is the heat flux at a transverse position adjacent to the bead portion (21a, 21b) at which the ribbon's thickness equals 1.05*tcenter, where tcenter is the final thickness at the ribbon's center line (17), and (ii) ?Q??(tb/tq?1)Q?q+10 kilowatts/meter2, where tb is the thickness of the thickest part of the bead portion. The cooling can take place along the entire length of the ribbon (15) or at selected locations, e.g.

Abstract: A flange (13) for use in direct resistance heating of a glass-carrying vessel (10), such as a finer, is provided. The flange comprises a plurality of electrically-conductive rings which include an innermost ring (140) which is joined to the vessel's exterior wall (12) during use of the flange and an outermost ring (150) which receives electrical current during use of the flange. The innermost ring (140) comprises a high-temperature metal which comprises at least 80% platinum and the outermost ring (150) comprises at least 99.0% nickel. This combination of materials both increases the reliability of the flange and reduces its cost. In certain embodiments, the flange can also include one or more rings (190) composed of a platinum-nickel alloy which has a lower thermal conductivity than platinum or nickel and thus can serve to reduce heat loss through the flange.