Looking (at) Glass
The glass of milk that you gulp down everyday…do you know how it gets to the dining table? I mean the glass...not the milk. Glass has a transparent, almost invisible presence in our lives. We look through it, we drink from it and it mirrors us.
Clear, chemically inert, non-reactive and hardwearing. These qualities
Glass was used as early as 4000 BC in the Middle East as a glaze to decorate beads. The earliest known clear glass is a vase found in Nineveh in Assyria, dating around 800 BC.
Conditioning: Forehearth brings glass to a uniform temperature and it is cut into segments of molten glass called gobs.
Forming: Gobs are forced into a shape and temperatures drop below 1,149° C. The cooling plate cools containers rapidly to below 482° C.
Molding: At the bottle machine a hollow is created in the gob. The hollow gob is called parison. Air is blown into the parison to bring it to
Annealing: Formed containers are placed in a machine where temperature is raised close to melting point and reduced below 482° C. The process strengthens containers.
Inspection: Fast Cooling machine brings temperatures down to 37.7° C. Defective containers are sent back into the furnace.
Finished glass containers are used to package products. When thrown
Melting: A furnace melts around 800 BC. sand, soda ash, limestone
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