Hot Dip Treatment Of Tempered Glass

Hot dip treatment, also known as homogenization treatment, is commonly known as "detonation". Hot dip treatment is the process of heating tempered glass to 290 ℃± 10 ℃ and holding it for a certain period of time to promote the rapid crystal phase transformation of nickel sulfide in tempered glass. This allows tempered glass, which was originally intended to self explode after use, to be artificially broken in advance in the factory's hot dip furnace, thereby reducing the self explosion of tempered glass during installation and use. This method generally uses hot air as the heating medium, and is referred to as "Heat Soak Test" or HST in foreign countries, which is literally translated as hot dip treatment.
Difficulties in hot dipping. From a theoretical perspective, hot dip treatment is neither complex nor difficult. But in reality, achieving this process indicator is very difficult. Research has shown that there are various specific chemical structural formulas for nickel sulfide in glass, such as Ni7S6, NiS, NiS1.01, etc. Not only do the proportions of various components vary, but other elements may also be doped. The speed of its phase transition highly depends on the temperature. Research has shown that the phase transition rate at 280 ℃ is 100 times that at 250 ℃, so it is necessary to ensure that each piece of glass in the furnace undergoes the same temperature regime. Otherwise, on the one hand, low temperature glass cannot completely phase change due to insufficient insulation time, which weakens the effectiveness of hot dip. On the other hand, when the glass temperature is too high, it can even cause the reverse phase transformation of nickel sulfide, causing greater hidden dangers. Both of these situations can lead to ineffective or even counterproductive hot dip treatment. The uniformity of temperature during the operation of hot dip furnaces is so important, and the temperature difference inside most domestic hot dip furnaces even reaches 60 ℃ during hot dip insulation. It is not uncommon for imported furnaces to have a temperature difference of about 30 ℃. So even though some tempered glass undergoes hot dip treatment, its self explosion rate remains high.