Why does tempered glass explode?

Edge and appearance quality of glass

The quality of glass edge is poor, and there are cracks and edges. The deep scratch on the glass surface is an important factor causing the explosion of tempered glass. The edge of glass is mainly characterized by longitudinal cracks. There are two main reasons for the edge of glass. On the one hand, the glass edge is impacted by external force, on the other hand, the polishing quality of the glass edge is poor and light. When the glass is tempered, the temperature loss of the front end of the glass (i.e. the furnace head) from the furnace to the arc is large, and the stress is relatively concentrated, which is easy to cause microcracks and cracks at the edge of the glass. The main feature of burst edge is shell-like defects on the inner and outer surfaces of glass edge.

Defects in product design

Defects in the design of tempered glass products are also hidden dangers that lead to spontaneous combustion and explosion cracking of glass. Defects in product design mainly refer to some glasses with holes, holes and corners. The design of holes or openings is too close to the edge of the glass, or the distance between two holes and two openings is too close, and the corners of the glass or the corners of the openings are too sharp, which leads to too concentrated stress on the glass and easy cracking of toughened products in later use.

Tempering process quality

Unreasonable tempering process will also lead to self-explosion of tempered glass products in the later stage. The main factors that lead to the late self-explosion of glass due to improper tempering process are: the degree of tempering of glass is too high, and the size of glass reaches or exceeds the load capacity of tempering furnace.

Nickel sulfide is mixed in the original glass.

If the glass caused by nickel sulfide does not disperse after self-explosion, it is easy to find the characteristics of an "8" or "butterfly spot" fragment pattern at the starting point of the fracture, and we will find a small black spot at the intersection of the "8" crack.

Improper installation of glass

There are two main reasons for the explosion of tempered glass caused by improper installation of glass. On the one hand, because the external force on the glass after installation is too large, when installing the glass, if the radian of tempered glass does not match the installation frame, it is forcibly installed with external force; On the other hand, the glass is exposed to the metal frame or metal screw; These two aspects will cause the later explosion of tempered glass.