Glass tempering furnace (also called glass annealing furnace or glass tempering furnace) is a device used for tempering glass during the production process. Tempering treatment is to form compressive stress on the surface of the glass and tension inside by heating and rapid cooling, thereby enhancing the strength and impact resistance of the glass.
The basic principle of glass tempering furnace includes the following steps:
Heating:
The glass plate or glass sheet first enters the tempering furnace and is heated to the softening point of the glass (generally about 620-650°C) by high temperature in the furnace. The purpose of heating is to soften the glass so that it can withstand pressure without breaking during the subsequent cooling process.
Uniform heating:
In order to ensure uniform heating of the glass, glass tempering furnaces usually use convection hot air systems or infrared heaters. This prevents the glass from generating thermal stress due to uneven temperature during the heating process, which may cause the glass to break.
Rapid cooling:
When the glass is heated to a certain temperature, it will pass through the cooling zone in the tempering furnace and be quickly cooled with cold air. The cooling speed is critical. It is usually necessary to quickly reduce the surface temperature of the glass within a few seconds to form compressive stress on the surface of the glass. This process hardens the outside of the glass while the inside remains at a high temperature and elasticity, forming a stress state of "internal and external tensile stress-external compressive stress" to enhance the strength of the glass.
Tempering effect:
Through heating and rapid cooling, compressive stress is formed on the surface of the glass, which significantly improves the glass's resistance to bending and impact. Tempered glass is usually harder and stronger than ordinary glass. Even if it breaks, it will form small granular fragments to reduce damage.
The main purpose of the glass tempering furnace is to improve the physical properties of glass by controlling the heating and cooling process. It is widely used in industries such as construction, automobiles, electronics, and home appliances.
