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.

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 present disclosure relates to the technical field of glass tempering, and in particular to a method and apparatus for weakening stress patterns of tempered curved glass. A through continuous reversible deformation cavity replaces an original split-type air box to serve as an air grid. A fluid smoothing structure is distributed in the cavity and configured for reducing fluid resistance. An outlet airflow orienting and stabilizing structure is distributed outside the cavity and configured for constraining the direction, flow velocity and flow quantity of a jetted airflow. A butt-joint device capable of changing with the curvature of the cavity surface is arranged between the cavity and an air supply source for the cavity.

A method for designing a quench box having first and second blastheads for tempering at least first, second and third sheets of glass each having a different shape is disclosed. The method comprises (i) using the shape of at least the first and second sheets of glass to calculate a first average surface; (ii) using the first average surface to calculate a quench surface of first and second quench modules of the first blasthead; (iii) using the first average surface to calculate a quench surface of a first quench module of the second blasthead; and (iv) using the shape of at least the third sheet of glass to calculate a quench surface of a quench module that replaces a quench module of the first and second blastheads when used to temper the third sheet of glass.

A tempering furnace for a glass sheet has a conveyor for the glass sheet, and first convection blow means over the conveyor to heat the glass sheet by hot air jets blown onto its top surface. With second convection blow means, pressurized air external to the tempering furnace may be led to second blow nozzles from which air is discharged as jets towards the bottom surface of the glass sheet. The heating effect of the air jets of the first convection blow means onto the glass sheet is adjustable by adjusting the feeding of electric current to electric elements inside blow enclosures, and the heating effect onto the glass sheet of the jets discharging from the second blow nozzles is adjustable by adjusting the blow pressure of feed pipes.

A method and an apparatus for tempering glass sheets. A glass sheet is heated to a tempering temperature and quenching is conducted by blasting cooling air to both surfaces of the glass sheet. The quenching of a top surface and a bottom surface of the glass sheet's both side portions is commenced earlier or is performed at the early stage of quenching more effectively than the quenching of a top surface and a bottom surface of the glass sheet's intermediate portion. As a result, the compression stress required for a desired tempering degree is established on both surfaces of the side portions earlier than on both surfaces of the intermediate portion. In order to achieve this, the cooling air enclosures above and below a glass sheet are provided with a subarea of weakened cooling effect.

A strengthened glass sheet product as well as process and an apparatus for producing the product. The process comprises cooling the glass sheet by non-contact thermal conduction for sufficiently long to fix a surface compression and central tension of the sheet. The process results in thermally strengthened glass sheets having improved breakage properties.