House Window Glass: How is Float Glass Made

The process of making float glass is so amazing that it’s almost akin to magic. Raw materials are inserted from one end and from the other end, specifically cut plates of glass start to emerge at a whopping rate of six thousand tons per week. The final product is destined to be used in various types of house windows.

How is window glass made, floating glass

However, to make all of this possible and have a successful window installation Chicago , there are 6 stages that need to be considered, as following:

1. Melting and refining

The first stage involves making the batch which consists of finely grained ingredients that are carefully controlled to ensure their quality is the best. The batch will then flow like a blanket on the glass that is molten in the melter at fifteen hundred degrees Celsius. The glass that results has almost optical quality and as much as two thousand tons of it are made at the same time.

The processes include melting the glass, refining it and homogenizing it and they all take part in various areas of the factory. In total, the melting process can last as long as fifty hours and it delivers glass that’s heated up at eleven hundred degrees Celsius. This is high quality glass that is smooth and free from bubbles and inclusions.

Keep in mind that the quality of the glass depends on the melting process and the composition can also be modified accordingly depending on what properties required for the finished product.

2. Float bath

At this point glass from the melter is going to flow on a mirror like surface made of molten tin, starting at eleven hundred degrees Celsius. It’s then going to leave the float bath as a solid ribbon at six hundred degrees Celsius. It’s been more than 6 decades since the same principle of float glass is used and surprisingly, there have been no changes about it.

However, the product did suffer some changes: they include a range for the equilibrium thickness that can be as little as less than 1 mm and as thick as twenty five millimeters. The ribbon no longer has striations, bubbles and inclusions, but it’s actually so clear that some call it perfect. When it comes to the float, it basically delivers what’s known as a fire finish that you’re probably aware of if you own new chinaware.

3. Coating

In order to change the optical properties of glass, special coatings can be applied using advanced temperature technology to the glass’ cooling ribbon.

CVD is currently regarded as the most important advance in the float process ever since it was invented and it can easily be used for laying down many types of coatings that are as thin as 1 micron. This is a special process that makes it possible to add several coatings in just a few seconds as the glass ribbon flows underneath the coaters. If things will eventually change regarding the CVD process, they’re certainly going to affect the composition.

4. Annealing

Even though float glass can be easily made, as it cools, the ribbon deals with a lot of stresses. For instance, if there’s too much stress, then the glass is going to break underneath the cutter. In order to have these stresses properly relieved, the ribbon is heat-treated in a long furnace.

5. Inspection

One thing that makes the float process so amazing and popular is the fact that it makes flawless glass. However, to make sure the quality is still amazing, inspection is a must. There are cases, though, when a tremor of the tin creates ripples into the glass ribbon, bubbles cannot be removed during refining and sand grains won’t melt.

When inspection is considered, computers will effectively steer cutters around the flaws. Current technology allows for up to one hundred million measurements a second which means that it’s very simple to locate flaws that the human eye cannot see.

The selvedge is cut by diamond wheels and the ribbon is also cut to the exact size specified by the computer. When it comes to the float glass, it’s usually sold by the square meter. The way it goes is that clients’ needs are translated into patterns of cuts by the computers in such a way that waste is minimized as much as possible. This way, not only are the clients going to get a high quality product, but the manufacturer doesn’t have to worry about wasting materials.

Check this world’s most advanced float glass plant: