Spontaneous breaking of tempered glass
Spontaneous breaking of tempered glass.
Sometimes tempered glass breaks without an obvious cause. When this happens breakage could be caused by; the glass being impacted in the same place over time (breakage can occur then or at a later time due to accumulation of tension in a particular area), pressure points in places where there are metal fittings (such as the screws in the profiles), the continuous tensioning of the glass (defective assembly, when the glass is tightened – when the fixing points are not coplanar), when the glass is too tight in the frame, if the glass edge is not finely finishing, shaving remains on the edges of the glass or if nickel sulphate inclusions are left in the float glass.
The probability of spontaneous breakage (in the case of nickel sulphate inclusions) is 1: 10000. This percentage is greatly influenced by the thickness as well as the temperature of the glass.
To reduce this probability, a test called the Heat Soak Test can be done. Spontaneous breaks cannot be eliminated, but by doing this test the probability is reduced by 100 times, the spontaneous breakage probability then being 1: 1000000.
The Heat Soak Test is a test in which the glass is heated to a temperature of 400 degrees, held there for about 2-4 hours and then cooled based on a calculated and pre-set temperature curve. If there are nickel sulphate inclusions, the glass will break. Any glass that passes the heat soak test is fit for installation.
My job involves Construction surveying at the various sites where we have ongoing projects and then designing the finished products, which we fully realise in the Glas Expert production halls. My duties also include troubleshooting installations and finding optimal solutions for execution, commissioning and exploitation by the final consumer of the glass products we made. These solutions are discussed and established together with the designers and architects, or directly with the project beneficiary.
Possibly the first time you’ve heard of it, or perhaps a printer comes to mind but you’re probably thinking about something to do with advertising, right? Well, Indeed, there is something called a UV printer, that can print on glass and is used in the advertising industry but that’s not it !