Float-glass process

In the float-glass process, adopted by all leading plate-glass manufacturers, the molten glass is allowed to float and soHdify on the surface of a pool of molten tin which provides an ideally flat surface. The endless glass ribbon has a surface so smooth that cosdy grinding and polishing are unnecessary. 

About two-thirds of the N2 produced industrially is supplied as a gas, mainly in pipes but also in cylinders under pressure. The remaining one-third is supplied as liquid N2 since this is also a very convenient source of the dry gas. The main use is as an inert atmosphere in the iron and steel industry and in many other metallurgical and chemical processes where the presence of air would involve fire or explosion hazards or unacceptable oxidation of products. Thus, it is extensively used as a purge in petrochemical reactors and other chemical equipment, as an inert diluent for chemicals, and in the float glass process to prevent oxidation of the molten tin (p. 370). It is also used as a blanketing gas in the electronics industry, in the packaging of processed foods and pharmaceuticals, and to pressurize electric cables, telephone wires, and inflatable rubber tyres, etc. 

These films are deposited at atmospheric pressure on the hot glass in a continuous operation (float-glass process). The CVD reactions are described in Ch. 11. 

Tin has many uses, including coating (tins/cans for food), alloys such as bronze, organ pipes, solder, and the float glass process. It is also important in laboratory syntheses, in spite of the well-known toxicity problems. 

For example one area well known in the chemical industry is process de-bottlenecking. Another example is the need for more environmentally friendly processes. Drucker s example is plate glass making by the float glass process (Pilkingtons). 

PiUdngton Brothers patent the float glass process... 

The glass plate produced by the "float-glass" process has a thin layer of tin metal on one side of the plate. This layer is useful for applying other coatings such as silver to the glass. 

Thinner glass qualities down to 2 mm thick are produced by stretching the still workable glass on the tin-bed. The float-glass process supplies flat glass in mirror glass quality, but is restricted to soda-lime glass. 

High-temperature cutting torches Reductive atmosphere for float-glass process Glass polishing... 

The relationship of this development, if any, to the later float glass process is not clear.)... 

Pilkington, Sir Alastair was born in 1920. He served in the Second World War. In 1942 he was captured on the island of Crete and spent the rest of the war as a POW. After finishing his studies at Cambridge University he joined the Pilkington glass company in 1947. By 1959 the float glass process was a success and the production of flat glass was revolutionized. He died in 1995. 

Pilkington Bros. Ltd., England, in 1937. (For a more recent process introduced by this firm see float glass process.) Pill Test. See slag attack tests. Pillar. (1) A column of brickwork for example the refractory brickwork between the doors of an open-hearth steel furnace. 

The Hall of Mirrors (La Galerie des Glaces) at the Palace of Versailles in France was begun in 1678, well before the development of the float glass process. What technology was available in the seventeenth century... 

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