Tempered glass is known to much today: do store show-windows of it, insert it into doors and cars, cars and vessels. Wide circulation of glass of special type is promoted by its unique qualities which are given to material when using special technology.
Production of tempered glass means several stages through which there goes normal sheet material. The main stage – training which gives to glass durability exceeding similar characteristic of normal material several times. But it is not the only plus of tempered glass. At its destruction it is not formed the sharp splinters capable to give wounds that speaks about safety of material when using in the most various spheres: construction, automotive industry, other industries.
Preparation has flown down also heating
At first carefully examine the selected material – in it there should not be bubbles, outside – scratches and other defects. Any defects inevitably lead to emergence of the internal stresses leading to cracking. If there is need, then on templates cut out preparations of the necessary form; at the same time their edges grind on special (facet) machines. All operations with preparations (drilling, cutting, other types of processing) will see to training.
The following step – heating. It has to be made in the conditions of uniform heating of surface. Temperature and duration of heating are connected. At the bigger duration of heating temperature has to decrease and vice versa. The room of cold glass in the furnace at initial stage causes its cooling, but then temperature is quickly restored to initial value. After short endurance in scorching heat, glass is moved to obduvochny grids.
Time of heating of leaf 6 mm thick in the furnace to 620-650os, is from 3 minutes 40 seconds to 5 minutes (depending on the chemical composition of material).
Cooling and control
It is possible to cool material in different ways: by means of oils, air, various liquids. However air-cooling is considered the most effective method. It consists in perpendicular giving on leaf of several air streams which go from snuffled, arranged in chessboard order. Number of producers in addition provides rotation of obduvochny grid so that each stream of air made rotational motion.
Correctly processed glass is capable to maintain 1800 wasps that allows to use it by production of electric stoves, fireplaces.
After glass cools down, quality control is carried out. For determination of thickness use micrometer which carry out measurements in 4 different points. The product has to be absolutely colourless; sorting is made depending on availability of defects (svil, bubbles, midge, etc.). For check of durability from height of 0.8 m drop on surface metal sphere weight in 800 g (thickness of plate less than 5 mm). At the same time glass has to be scattered on pieces no more than 3.2 cm in size.