The dry mixture of raw materials is heated to 1560°C in a melting furnace. The melting point of glass is even higher then it is for steel.
When the glass is melted, it is poured into the so-called Float. This immense basin is filled with hot, liquid tin having about 1000°C. The liquid glass is pulled carefully over the surface of the tin and disperses uniformly like an oil film on water. This way, the absolutely smooth surface can be achieved.
Schematic description of the manufacturing process
In the float basin, the liquid tin stands on a level of about 8 cm, this stands for a capacity of 200 tons. With the help of conveyance wheels, the glass is pulled over the tin and gets a uniform thickness and a high planeness. The pulling speed of the conveyance wheels are decisive for the thickness of the final glass.
Schematic description of the float basin
Behind the float basin, the glass has passed about 70 meters since the furnace. It has cooled down to 620°C and now forms long sheet of solid glass. This sheet is lead into a cooling furnace and cut into larger pieces immediately afterwards.
It is characteristic for a floatline, that it is permanently running. Only a stable process and a constant, continuous production flow can accentuate the economies of scale to its full extend. After approximately 15 years of non-stop production, a floatline needs to be replaced.
Discover our Floatglasses for solar applications: