Innovations

← Back
May 07, 2018

Float Glass Annealing Lehr

After the formed glass ribbon leaves the tin bath, the glass is at a temperature of 530C. If the glass ribbon were allowed to cool in free air, the surfaces would cool much more rapidly than the internal body of the glass. This would cause the surface to be in severe compression and would also cause unwanted internal stresses in the ribbon.



The thermal history of glass during and immediately after forming is such that internal stresses are bound to be present. It is therefore necessary to bring the glass to ambient temperature gradually by a controlled thermal treatment - annealing. In practice, annealing is carried out in a long annealing lehr oven, 6m wide and 120m long, with a predetermined temperature gradient through which the glass passes. In the case of containers and table ware, the product is transported on a conveyor belt and for flat glass on a special roller conveyor. Controlled electric heating elements are precisely located in the lehr to maintain a consistent temperature profile across the width of the glass ribbon.

The end result of the annealing process is glass which has been carefully cooled to ambient temperatures over a long distance, without the introduction of temporary or residual stresses.

Our latest innovations

May 07, 2018

History of Glass


How to turn Sand into Glass The raw material from which glass is made is silica, the most abundant of all the earth's minerals. Milky white in color, it is found in many forms of rock, including granite. And as every beach in the world has been ... Read More→

May 07, 2018

Float Glass Cutting and Packing


The final manufacturing process for float glass is the Cutting and Packing line. The cutting and packing conveyor is comprised of special roller sections that are capable of transporting glass product without damage. All cutting equipment and se... Read More→

May 07, 2018

Float Glass Annealing Lehr


After the formed glass ribbon leaves the tin bath, the glass is at a temperature of 530C. If the glass ribbon were allowed to cool in free air, the surfaces would cool much more rapidly than the internal body of the glass. This would cause the surfa... Read More→

May 07, 2018

Glass Materials and Batching


Glass contains three major categories of constituents - formers, fluxes, and network modifiers. Silicon dioxide (SiO2), or sand, is used as the former and basic constituent with soda ash (Na2CO3) as the flux. Lime (CaCO3) and dolomite (CaCO3MgCO3) a... Read More→

May 07, 2018

Glass Melting Process


Melting The typical melting furnace is a Six Port Cross Fired Regenerative furnace with a capacity of 500 tons per day. Cross fired regenerative furnaces have been built for very small and very large melting areas. The smallest units may be unecono... Read More→

April 10, 2018

Glass Coating Technology Comparison


A variety of techniques are available to deposit thin films onto flat glass. The most widely used of these for producing high quality functional coatings can be subdivided into two classes: Physical Vapor Deposition (PVD) and Chemical Vapor Depositi... Read More→

March 21, 2018

Building Wealth in Float Glass


Float glass manufacturing is a wealth generating industry. Float glass was invented in the 1950s, and the industry has grown steadily since then. Float glass offers a promising opportunity for investors that are aware of a populous area with unmet g... Read More→