Manufacturer - uPVC Window & uPVC Doors



About Glass


Glass is a combination of sand and other minerals that are melted together at very high temperatures to form a material that is ideal for a wide range of uses from packaging and construction to fiber optics. A form of glass occurs naturally within the mouth of a volcano when the intense heat of an eruption melts sand to form Obsidian, a hard black glassy type of stone. Man first used this as tips for spears.


Today man has mastered the glass-making process and can make many different types of glass in infinitely varied colors formed into a wide range of products. Glass, chemically, is actually more like a liquid, but at room temperature it is so viscous or 'sticky' it looks and feels like a solid. At higher temperatures glass gradually becomes softer and more like a liquid. It is this latter property, which allows glass to be poured, blown, pressed and moulded into such a variety of shapes.



Types of Glasses



1. Float glass: Standard flat, clear window glass is called float glass; named after the manufacturing process that creates it. During production, soda lime glass, calcium, silica sand, soda, oxide and magnesium are mixed together and melted in a furnace at a temperature of around 1500°C. The molten glass is then poured into a molten tin bath. The tin is fluid but the glass is still viscous, so they do not mix and instead stay flat like the contact surface between them. The glass partially cools, and is then put into a lehr (annealing chamber), where it undergoes a controlled cooling process until it reaches room temperature.


2. Low-emission glass: (Low-E) is a clear glass that has a microscopically thin coating of metal oxide. This filters the sun's heat while allowing a considerable amount of light to enter. Low-E glass is a type of insulating glass, which increases the energy efficiency of windows by reducing the transfer of heat or cold through glass. That means in cold temperatures your house stays warmer, and in the hot temperatures it stays cooler by rejecting the sun's heat and damaging rays reducing air conditioning and artificial lighting costs.


3. Reflective Glass: Reflective window glazing is commonly used in hot climates where solar heat gain control is critical. Reflective Glass reduces heat and light with a metal oxide coating that provides a mirrored effect. In addition to daytime privacy and minimized ultraviolet damage, Reflective Glass provides a dramatic visual impact and is often used as an architectural design element.


4. Tempered glass: Tempered or toughened glass undergoes a different manufacturing process to normal glass, this glass is designed to be around 3 times as strong as normal glass. As soon as the glass is removed from the furnace, it receives a continuous and uniform air quench, where air is blown across it to cool it to a temperature of around 400 - 600 °F and thus causing the material to harden. The tempered glass is then fit for security applications. Tempered glass is tougher to break than ordinary glass, and when broken just shatters into small fragment that avoid causing major harm.


5. Laminated glass: Another kind of security glass is laminated glass this is secure in the way that when someone tries to break the glass because there is a sandwich effect from the glass between PVB or resin it holds together when forced. This coating over the glass means when it is hit it may crack but the pieces are held together preventing splinters of glass. For this reason it is also installed to delay the spread of fires.


6. Double Insulated Glass: Double Glazing is simply a glazing process in which a window is formed by using two panes of glass with a space between the panes. The space between the two panes is of variable thickness, usually several millimeters. The trapped air between the panes acts as an effective layer of insulation. The double layer of sealed glass is manufactured to a required size and before the unit is sealed a drying agent is added to ensure that no moisture is present. In order to remain effective it is important to ensure that no moisture is present and that it is airtight. Following manufacture of the sealed unit the pane of double thick glass is added to a suitable frame chosen by the customer.


7. Body-tinted glass It is a normal float-clear glass into whose melt colorants are added for tinting and solar-radiation absorption properties. This reduces heat penetration in buildings. Coloured glass is an important architectural element for the exterior appearance of windows, doors and facades.