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Making Flat Glass

Flat glass is used in windows because it is strong, clear, and weatherproof. In the past, making flat glass was time-consuming and costly, but now it can be made cheaply and easily due to the float glass method. This multi-phase method was discovered in 1959 by a British company called Pikington.

In the first phase, glass ingredients are put into a melting furnace. This produces molten glass. Next, the molten glass is gently poured into a tank of molten tin. This tank is called a float bath because a layer of molten glass floats on the surface of the molten tin. Molten tin is used in the float bath because it has a smooth, mirror-like surface. The molten glass can be made thicker or thinner by controlling how fast it flows through the float bath.

The flat layer of glass is then moved along rollers and cooled very slowly in a low tunnel called a lehr. In the next phase, the glass is washed and then cut into sheets using diamond wheel cutters. Finally, the sheets of glass are stacked together and taken to the warehouse.


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