Solution for self explosion of tempered glass (3) - Hot dip treatment

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 the tempered glass. This allows the tempered glass, which was originally intended to self explode after use, to be artificially crushed 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 called "Heat Soak Test" or HST in foreign countries, which is directly translated as hot dip treatment.
Difficulties in hot dipping. From a principle 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 they may also be doped with other elements. The speed of its phase transition highly depends on the temperature. Research has shown that the phase transition rate at 280 ℃ is 100 times higher than 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 fully transform 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 can even reach 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 has undergone hot dip treatment, its self explosion rate remains high.