A tool for local cooling by contact of a glass sheet at a temperature higher than 450° C., known as a contact tool, includes a contact face suitable for coming into contact with the glass sheet, the tool including an internal pipe for the circulation of a coolant, in particular air. The tool is used in a device for bending and/or cooling a glass sheet, in particular individual, the tool coming into contact with the glass sheet while it is held by a bending tool or by a cooling frame after bending. A compression zone is created that is capable of being drilled to form an edge having compressive stresses.

A process for manufacturing a bent laminated glazing, includes manufacturing a first bent laminated glazing including at least two glass substrates locally comprising, in each of the at least two glass substrates and facing each other in all the at least two glass substrates, a zone including compressive stresses, and cutting the first bent laminated glazing through its entire thickness along a line included in the zone in order to form local cut edges and, after cutting, a second bent laminated glazing with the local cut edges having compressive edge stresses.

A nozzle strip for a blow box for thermally prestressing glass panes, which nozzle strip has a row of nozzles each having a nozzle inlet and a nozzle opening for impinging on a surface of a glass pane with a stream of air through the nozzle openings, wherein the nozzle openings are arranged on merlon-like elevations of a side surface of the nozzle strip.

Glass laminates, comprising more than one glass composition, are becoming increasingly common as the industry moves towards lighter and stronger glazing. Bending dissimilar glass compositions can present problems. A mismatch in the glass viscosity curves, especially in the viscoelastic region of the compositions can result in one layer becoming softer than one of the other layers during the thermal bending process. As a result, economical processes, such as gravity or press bending in which multiple glass layers are simultaneously bent, may not be practical to use forcing the use of more expensive single glass layer bending processes. By thermal treatment processes the fictive temperature of at least one of the glass compositions prior to bending can be shifted to better match the other compositions allowing the glass layers to be simultaneously bent.

A system for positioning an optical preform in a furnace is provided that includes an upper muffle and a downfeed handle assembly with a tube defining a first end and a second end, the second end extending into the upper muffle. A handle is disposed within the tube. A second end of the handle extends into the upper muffle and a seal assembly is positioned around both the tube and the handle. The first end of the handle extends through the seal assembly and a drive assembly is coupled with the downfeed handle.

The present description concerns a gas cooling cell, comprising: a chamber; at least one opening in the chamber, of access to a treatment space internal to the chamber; at least one door for closing the opening; and a system (4), internal to the chamber, comprising at least one wall (42) mobile between a first position where this wall forms a screen between the opening and the treatment space, and a second position where said wall clears the access to the treatment space from the opening.

The present description concerns a gas cooling cell, comprising: a chamber; at least one opening in the chamber, of access to a treatment space internal to the chamber; at least one door for closing the opening; and a system (4), internal to the chamber, comprising at least one wall (42) mobile between a first position where this wall forms a screen between the opening and the treatment space, and a second position where said wall clears the access to the treatment space from the opening.

A method for heat strengthening or tempering glass sheets of a glass load containing several glass sheets, in which the glass sheets are heated in a furnace to a tempering temperature and the glass load is transferred at a transfer speed (W) away from the furnace into a tempering unit, in which the actual quenching is conducted by blasting cooling air onto both surfaces of the glass sheets. By an initial blasting unit, located between the furnace and the quenching unit and divided into initial blasting zones in the direction transverse to the motion of the glass, is blasted compressed air onto the surface of the leading and trailing edges of a glass sheet, to the direction of which normal it is desired to straighten the end in order to decrease end-edge kink.

Glass stack configurations including a carrier plate, setter plates, and glass sheets for thermal treatment of the glass sheets to form glass ceramic articles are provided. The glass stacking configurations and components described herein are selected to improve thermal uniformity throughout a glass stack during ceramming processes while maintaining or even reducing the stresses in the resultant glass ceramic article. Accordingly, the glass ceramic articles made according to the various embodiments described herein exhibit improved optical qualities and less warp than glass ceramic articles made according to conventional processes. Various embodiments of carrier plates, setter plates, parting agent compositions, and methods of stacking glass sheets are described.

The disclosure relates to glass compositions having improved thermal tempering capabilities. The disclosed glass compositions have high coefficients of thermal expansion and Young's moduli, and are capable of achieving high surface compressions. A method of making such glasses is also provided.