Heating principle of glass tempering furnace

　　At present,the physical tempering method commonly used in glass tempering furnaces is to heat the glass to a softening point(about 650°C).At this time,the glass can still maintain its original shape,but the particles in the glass have a certain migration ability,so the structure is adjusted.So that the internal stress is quickly eliminated,and then the tempered glass is blown and quenched.When the temperature is balanced,compressive stress is generated on the surface of the glass and tensile stress is generated in the inner layer,that is,the glass has a uniform and regular distribution The internal stress improves the tensile strength of the glass as a brittle material,so that the bending and impact strength of the glass is improved.

　　At the same time,due to the existence of uniform internal stress in the glass fired in the glass tempering furnace,once the glass is partially broken by an impact that exceeds its strength,it will explode into small particles under the action of the internal stress,which improves its safety.Therefore,tempered glass can also be called prestressed glass or safety glass.

　　When the temperature in the heating glass tempering furnace is uneven,the air flows from a low temperature to a high temperature.When the air temperature is higher than the glass temperature,the glass is heated.

　　Because the furnace door is opened or cold air enters from the place where the heating furnace is not tightly sealed,this cold air locally reduces the furnace temperature and glass temperature.In actual production,opening the furnace door has a greater impact on the temperature,often before and after heating the glass tempering furnace Add a corner furnace wire to the upper and lower parts of the furnace to balance the temperature.In the rear furnace door,because of the fear of cold air from the air grille being blown into the furnace,an air curtain is often used to isolate the exchange of cold and hot air.

　　Some glass tempering furnaces mainly use convection for heating.The hot air is drawn from the heating furnace of the small tempering furnace,and a small and high-temperature-resistant electric blower is used to blow the hot air through the pipe to the air hole or the nozzle to the upper and lower sides of the glass.Therefore,the hot air runs in a sealed cycle,which effectively prevents cold air from entering the furnace.