Glass can sometimes break during the tempering process, which is not necessarily an issue with the tempering furnace; it's related to many factors. We need to understand the specific causes and solutions to minimize such occurrences.

Reason 1: The glass substrates have quality issues, including the use of poorly annealed glass or glass with large bubbles and impurities.

Solution: Only high-quality glass blanks can ensure the quality of tempered glass.

Reason 2: The glass has cracks or the edges of the glass are not properly handled.

Solution: Utilize glass with minimal surface cracks or good edge finishing.

Reason 3: Poorly handled glass drilling edges or glass drilling diameter smaller than the glass thickness.

Solution: Address the edges of the drilling and increase the diameter of the glass drilling.

Reason 4: The glass drilling location is too close to the edge of the glass.

Solution: A straight slot can be cut using a cutting machine at the edge of the drilling to allow for adequate heat absorption during tempering.

Reason 5: Utilizing double tempering with tempered glass.

Solution: Tempered glass has formed into particles, and re-tempering it is akin to glass detonation. If there are any defects in the glass, it is prone to shattering within the tempering furnace. To be precise, it is strictly prohibited to re-temper glass.