In the manufacturing of flat glass, it is the process of controlled cooling, which is done to prevent residual stresses in the glass.
American Society for Testing and Materials
A vessel that employs high pressure heat used to produce a bond between glass and PVB or urethane sheet, creating a laminated glass product.
Flat glass that is curved into shapes while still hot.
The process of edge finishing glass to a beveled angle.
A noticeable imperfection in glass.
Bubbles in a coating film that forms during the heat treating process.
Bow (or Warp)
A curve, bend or other deviation from flatness in glass.
The resulting pattern formed by the cracks in glass when broken. Also called the fracture pattern.
A gas pocket in the interlayer material or between the glass. In flat glass, a inclusion greater than 1/32" in diameter.
The extreme lateral edge of the ribbon, as drawn in the flat glass manufacturing process.
Bullet Resistant Glass
The multiple lamination of glass. Glass and plastic that are designed to resist penetration from small fire arms.
The installation of glass where the vertical glass edges are without structural supporting mullions.
A term sometimes used for tempered glass.
Tension stresses within the center portion of heat-treated glass.
An inorganic and non-metallic coating used to be fused to a substrate.
Very small cracks in flat glass usually at the edge.
Chemically Strengthened Glass
Glass that has been heat treated from ion-exchange to produce a compressive stress layer at the treated surface area.
An imperfection due to breakage.
A method of making flat glass. Blowing a large bulb, opening it up, and spinning it flat.
A lightly pitted area on the glass surface, resulting in a dull gray appearance.
Broken glass, extra glass from a previous melt or the edges that are trimmed off glass to size. Cullet is one of the essential ingredients in the raw batch in glass-making, it facilitates the melting process.
Glass cut to a specified width and length.
Scoring glass with a diamond, steel wheel or other alloy wheel and breaking it along the score.
A manufacturing process of flat glass. Molten glass is blown and drawn into the form of a cylinder, which is subsequently split longitudinally, reheated, and flattened.
Deflection of Glass
The amount of bending of the center of glass.
The cubical pattern of a fracture in fully tempered glass.
Deep, short scratches.
A small particle of foreign material imbedded in the surface of flat glass.
Alteration of viewed images, caused by the variations in the flatness of glass.
Windows which have a layer of inert gas sealed between inner and outer pains. The gas that is typically used in this type of window is either argon or krypton.
Double Strength Glass
Float glass, approximately 1/8" (3mm) thick.
Glass produced by a continuous drawing operation.
Compressive stresses at the edge of heat-treated glass.
A specified finish to the edges of glass. Sometimes called Edgework.
Grinding the edge of flat glass to the desired shape or finish.
To alter the surface of glass. Usually by hydrofluoric acid or other caustic sources. Permanent etching of glass can occur from long term, high alkali contact.
Any debris resulting from the processing and fabricating of glass prior to the tempering process.
Any glass panel, window, door or skylight on a building.
A term that describes flat glass, sheet glass, plate glass, cylinder and rolled glass.
A pool of molten metal, usually tin, in which molten glass is drawn into a flat sheet.
Glass formed on a bath of molten tin. The surface in contact with the tin is known as the tin surface. The top surface is known as the air surface.
Glass in particulate form.
Surface treated to simulate frost.
Fully tempered glass
Flat or bent glass that has been heat-treated to a high surface and edge compression to meet ASTM C 1048 Standards. Fully tempered glass, if broken, will fracture into many small cubical pieces, known as dicing. Fully tempered glass is approximately four times stronger than annealed glass of the same thickness.
Glass Association of North America.
A round or elongated bubble in glass.
A hard brittle substance, usually transparent, made by fusing silicates, soda ash and lime stone, under high temperatures.
A general term used to describe glass, panels, etc. Also the process of installing glass or panels into a prepared opening in windows, door panels, partitions, etc.
Glazing Select Quality
This represents the flat glass supplied when quality is not otherwise specified. (Typically q^3 from ATSM C 1036 Standard.)
The degree of shine or luster on the surface of glass, ceramic enamel or ink.
Glass that absorbs a significant amount of solar energy.
Glass able to withstand high thermal shock, usually because of its low coefficient of expansion.
Flat or bent glass that has been heat-treated to a specific surface and edge compression to meet the requirements of ASTM C 1048. Heat-strengthened glass is approximately two times as strong as annealed glass of the same thickness. Heat-strengthened glass is not considered safety glass, because it will not dice like fully tempered glass.
Term used for both fully tempered glass and heat-strengthened glass.
Those manufacturing operations dealing with hot glass, which are melting, forming, and annealing.
A foreign solid or gas within the glass matrix.
Two or more pieces of glass spaced apart and hermetically sealed to form a single-glazed unit, with an air space between each lite. Commonly called IG units.
Any material used to bond two lites of glass together to form a laminate.
International Window Cleaning Association.
An abrupt deviation on flat glass most commonly found near the edge of heat-treated glass.
Two or more pieces of glass permanently bonded together with interlayer.
Pieces of glass bonded together at their edges. Usual with soldered lead.
A long, tunnel-shaped oven for annealing glass, usually by a continuous process for slow cooling.
Another term for a pane of glass.
The glass melting assembly, including the melter, regenerators, flues, refiners, forehearths, channels, throats, etc.
Horizontal or vertical bars that divide the glass area into smaller lites of glass.
National Glass Association.
A surface cavity formed by a gaseous inclusion.
Roughness or waviness on the surface of glass which resembles the skin of an orange in texture.
Rolled glass with a pattern imprinted on one or both sides. Usually used for light control on bath enclosures or decorative glazing.
Pilkington Float Glass Process
The process of making flat glass with a continuous pour of glass onto a molten tin bath.
Pittsburgh Sheet Process
The method of making sheet glass by drawing it vertically upward from a bath.
Flat glass formed by the rolling process, then ground and polished on both sides.
A device for examining the amount of strain in a glass sample.
Pyrolytic Coated Glass
A thin Low-e coating applied to the hot surface of glass when manufactured.
The thermal resistance of a glazing system.
A glass batch without cullet.
A glass batch made of only cullet.
Glass with a metallic coating to reduce solar heat gain.
A continuous length of glass in process.
Roller Distortion or Roller Wave
A waviness resulting in horizontal heat-treated glass, as a result of glass being transported through the furnace on rollers.
Small scratches in glass, generally caused during shipping.
Flat or bent glass that is heat treated or laminated, and if broken would not cause serious injury.
To penetrate the surface of glass with a cutting device, such as a glass cutter.
Coating applied to glass surfaces to reduce scratching effects.
Any marking or tearing of the glass surface.
Sealed Insulating Glass
(Same as "Insulating Glass ")
To grind or sand the sharp edges of a piece of glass, usually with a belt or wheel.
Small bubbles in flat glass, less than 1/32" in diameter.
Flat glass made by continuous drawing in the vertical direction.
The process of applying silver to the back of mirrors.
Windows with just one layer of glass. This type of window offers little protection against heat and cold.
To cut a piece of glass to a specific size.
Solar Control Glass
Tinted or coated glass that reduces solar heat gain through a glazed product.
Discoloration of glass.
Crystalline inclusion imbedded in the glass.
Flat glass between 0.115 and 0.134 in. thick.
Flat glass between 0.085 and 0.101 in. thick.
Any tension or compression existing in the glass, usually as a result of incomplete annealing.
Surface stresses in heat-treated glass, resulting from rapid cooling of glass surface to produce compressive stresses at the surface.
The amount of residual stress in annealed glass.
A term for glass subjected to heat treatment, followed by rapid cooling, to produce a compressive surface layer.
A term sometimes used by foreign manufactures to identify heat-treated or fully tempered glass.
Windows which seal two layers of inert gas within three panes of glass. Also known as Pane Insulated.
Sodium silicate glass that is soluble in water.
An opening constructed in a wall to admit light or air, usually framed with glass and sometimes mounted to permit opening and closing.
Flat glass with wire mesh embedded in the glass.