The reasons for the self-explosion of tempered glass

In fact, from the birth of tempered glass, it is accompanied by the problem of self-explosion. The self-explosion of tempered glass can be expressed as the phenomenon that the tempered glass automatically breaks without external direct action. Tempered glass blast can occur in the process of tempering processing, storage, transportation, installation and use.

Self-explosion rates are inconsistent with manufacturers, ranging from 3% to 0.3%. Generally, the self-explosion rate is calculated in units of the number of pieces. The area size and glass thickness of the single piece of glass are not considered, so it is not accurate enough, and it is impossible to make a more scientific comparison. In order to uniformly measure the self-explosion rate, a unified assumption must be determined. Uniform conditions are determined: every 5 to 8 tons of glass contains a nickel sulfide sufficient to cause self-explosion; the area of each piece of tempered glass is 1.8 m2 on average; nickel sulfide is evenly distributed. Then calculate the self-detonation rate of 6mm thick tempered glass from 0.64% to 0.54%, that is, the self-explosion rate of 6mm tempered glass is about 3‰~5‰. This is basically consistent with the actual value of domestic high-level processing enterprises.

Even if it is completely produced according to the standard, it cannot completely avoid the self-explosion of tempered glass. Large buildings can easily use hundreds of tons of glass, which means that there is a high probability of nickel sulfide and heterogeneous impurities in the glass. Therefore, although the tempered glass is subjected to hot dip treatment, self-explosion is still inevitable.

There are two mian reasons for self-explosion.

First, self-explosion caused by visible defects in the glass, such as stones, sand, bubbles, inclusions, notches, scratches, blasts, etc.;

Second is the self-explosion of tempered glass caused by nickel sulfide (NIS) impurities and heterogeneous phase particles in the glass. BALLANTYNE first proposed the mechanism of nickel sulfide self-explosion of tempered glass in 1961. BORDEAUX and KASPERr have found that the diameter of nickel sulfide causing self-explosion is between 0.04 and 0.65 mm and the average particle size is 0.2 mm. Newly discovered heterogeneous particles cause self-explosion of tempered glass.

Also, there are other factors in the self-explosion of tempered glass: unreasonable glass slotting and drilling, poor quality of original glass, uneven thickness such as embossed glass, uneven stress distribution such as curved tempered glass and regional tempered glass.

Joysun's tempered glass can be proceeded by heat soak test to low the glass self-explosion.