Glasses and its manufacture Presented by Kavinilavan k
History & applications Archaeologists have found evidence of man-made glass which dates back to 4000BC. They are used in car doors, windows,home appliances,lights,etc.,
Manufacture In olden days glasses are made by hand. They take long time and more man power. Now-a-days making of glass are machinated. From olden days to now,sand is the important raw material in making glass.
Raw materials Sand SAND SODA ASH (grade A to G) Soda ash Lime stone LIME STONE DOLOMITE Dolomite Alumina ALUMINA
MELTING & REFINING The raw materials are mixed and melted in gas furnace up to all the raw materials are completely melted. In this process impurities are come upwards & they are removed. It will take 50 hours to melt. Capacity of furnace is 2000 tones.
Float bath Molten glass float through tin. Glass enters the bath at 1,100 degree and leave the bath at 600 degree Celsius. Because tin more denser than glass,glass float on them & they form smooth and bubble less flexible glass at last.
coating After float bath & In this stage glass is coating called ribbon glass. Variety of chemicals are coated at thickness of less than micron based on its purpose. This process is called chemical vapor deposition (CVD)
Annealing Annealing means cool down the substance by slow and steady process. Glass will broke when cooled suddenly, so it will be gradually cooled to normal temperature. After this process we get a fine smooth glass plate.
Cutting & quality control These glass plate are cut into proper size using diamond cutter. After this all the glass plates are check for its quality and optical view.