What’s the process of glass production?
How is glass produced in modern society?
An incredibly important advancement in how glass was manufactured is through the technique of adding lead oxide to molten glass; as it improves the appearance of the glass, which made it easier to melt using sea-coal. This technique increased the “working period” of glass, making the substance easier to manipulate. The process was originally discovered by George Ravenscroft in 1674, who was the first person to produce clear lead glassware on an industrial scale. Ravenscroft was fortunate enough to have the cultural and financial resources at his disposal, as this allowed the revolution of the glass trade. In this sense England overtook Venice as the centre of the glass industry throughout the eighteenth and nineteenth century. Seeking to find an alternative to the average glass production, he used flint as a source of silica. He was granted the patent in 1673, which allowed for production and refinement to be moved from his glasshouse on the Savoy to the seclusion of Henley-on-Thames.
By 1696, after the patent was expired, twenty-seven glasshouses in England were produced using flint glass, with these being exporting all over Europe. Rather than reducing the lead content in the glass, glass manufacturers responded by creating highly decorated, more delicate forms, known to collectors today as Excise glasses.
An early advance in the automation of glass manufacturing was patented in 1848, by then engineer Henry Bessemer. His system produced a ribbon of flat glass by forming the ribbon between rollers. The surfaces of the glass first needed polishing.
The mass production of glass was first developed in 1887 by the firm Ashley Yorkshire, England. This semi-automatic process would use machines that were capable of producing 200 bottles per hour, which was much quicker than the traditional methods of manufacturing.
The “Float Glass” process
In 1898, Pilkington invented Wired Cast glass, which incorporated a strong steel-wire mesh for safety and security in glass. This greatly post-dates the Georgian era. The Machine Drawn Cylinder technique was invented in the USA, being the first mechanical method for the drawing of window glass. It was manufactured under licence in the UK by Pilkington from 1910 onwards.
Pilkington improved the plate polishing process in 1938, incorporating a double grinding process to give an improved quality to the finish of the glass. Between 1953 and 1957, Alastair Pilkington and Kenneth Bickerstaff developed the revolutionary float glass process, which would go on to become the first successful commercial application of forming a continuous ribbon of glass using a molten tin bath. The use of this method gave the sheet uniform thickness and a flat surface. Modern windows are produced from float glass.
For more on glass and its production, please visit the glass manufacturers website!