What Makes Tempered Glass So Effective?
Tempered glass, commonly referred to as toughened glass is made up of cut-to-size glass sheets that are fed into the tempered furnace, reaching heat levels of approximately 650°C to ensure optimal malleability. The glass is then moved into the quench where it is rapidly cooled by blasting both sides with air. This rapid quenching induces compressive stresses to the glass surface, while the centre remains in tension. Although the physical characteristics remain unchanged, the additional stresses created within the glass increases its strength by 4 – 5 times that of annealed glass of equal thickness!
In addition to clear glass, it also offer various tints, Low-E glass, hard-coat reflective glass and some temperable soft-coat reflective glass – offering a dynamic and well-rounded selection that provides the same strength and protection. In the event of breakage, the panel will fracture into relatively small harmless particles to ensure the safety of building inhabitants, reducing the amount of large, sharp pieces that can cause injury.
Compared to annealed glass, tempered glass maintains a greater resistance to thermal stress (temperatures 70°C to 290°C). Thanks to its mechanical strength, it is ideal for creating a frameless or ‘transparent structure’ concept in all glass assemblies, including shop fronts and curtain walls. For the same reason, tempered glass is highly recommended for doors, side panels, glass balustrades, shower screens, and even glass walled squash courts. Using this type of glass in automotive and furniture applications can create a safer and well-protected shield when faced with accidents or applied pressure.
What is Heat Strengthen Glass?
Heat strengthen glass, commonly referred to as half-tempered glass, is a process quite similar to tempered glass. However, with heat strengthened glass, the sheets are quenched at a slower rate over a longer period of time. This results in lower compressive stress, increasing the strength to only twice that of annealed glass of equal thickness. Heat strengthen glass has less distortion when compare with tempered glass, although it has greater resistance to thermal stress when compared to annealed glass. Since glass usually breaks into large pieces when damaged or shattered, this type of glass is normally used with laminated coating for skylights since when and if the glass is broken, the fragmented pieces can be retain by the interlayer, rather than falling down as tempered laminated glass would.
Innoglass Performs Efficient Heat Soak Testing to Ensure the Highest Quality
Heat soaking is a destructive test that ensures each sheet of glass is able to endure pressure from heat and stress. During these tests, Innoglass applies 280°C±10°C of heat temperatures to the glass for several hours. This speeds up the Alpha to Beta transformation of any nickel sulphide (NiS) that is present. What does this accomplish? By accelerating the testing process, it reduces the likelihood of breakage by a factor of 20, or 5 lites per 1000 panes. Additionally, the ability to identify NiS inclusion, prior to on-site installation, can:
- Reduce the risk of spontaneous breakages after installation
- Increase safety and security
Innoglass strongly recommends tempered laminated glass application in any area that is highly populated, where the consequence of breakage could result in injury.