The recipe for our basic Float Glass
Glass is made from very basic substances. But when those basic ingredients go through our process, they transform into the durable and advanced building material that we love.
Take some high quality sand (the kind you’d imagine on your dream beach), soda ash, limestone, saltcake and dolomite and melt at white heat to a high consistency and you’ve got glass.
But here’s a little more detail for those of you who want to learn more about how we create our base form glass….
All those raw materials we mentioned before – we call them the batch. And the first thing we do is make sure the batch is up to scratch – that is, each component is measured out rigorously and blended to ensure the mix stays consistent and within our tight tolerances for these things. Only then can the batch pass through the furnace.
The Furnace: Melting and Refining
After we determine that the batch is ready,an automated conveyor progressively adds the mix to the filling end of the gas fired regenerative furnace. The blank of solid granules of the newly introduced batch mix rest briefly on the surface of the already molten glass, before the 1550°C temperatures in the melter see them melt and combine. The molten glass stays in the furnace long enough to allow the components to combine and react together and allow bubbles of gas to escape – ensuring glass of consistent colour and density, and as free from distortion and faults as practically possible.
We use world leading technology to apply coatings that impart clever thermal properties and other desirable benefits to the glass. There are a number of coatings that can be applied depending on the end-product. One common coating is low emissivity (Low E) coating, which could go on to improve the energy performance and comfort of your space, if the end-product ends up near you.
Another form of coating is the pyrolytic coating process – or so-called “hard coating” process – deposits and fuses microscopically thin layers of metal oxides to the surface of the glass, producing extremely durable coated products that can easily be handled, transported and processed.
Since the glass we send you isn’t generally still firing hot, you might have guessed we have a cooling process.
The annealing lehr, which is essentially a very long cooling rack for the glass “ribbon” produced at the hot-end of the process, removes stresses in the glass by carefully cooling it down from 600°C to room temperature. Careful controls applied in this process ensure that the glass can be smoothly cut when fully cooled – both for cutting the ribbon into the large stock sheets that come of here at the manufacturing line, and for all the subsequent cutting and processing of those sheets after they’ve been shipped out to processing factories.
This makes sure that in the end, you get a sheet of glass that’s of the highest standard for clarity, flatness, and edge quality, with almost no optical distortion and residual stresses in the glass.
So that’s how you make float glass, what else is there?
When it comes to creating our performance glass, this process isn’t quite enough. There’s lots of other stages in between, and other ways we form glass besides our basic float glass.
You may be interested in learning about how we create our stock laminates!