Tempered glass is the most commonly used glass deep-processed product. Windshield, window glass for vehicles, trains, etc., glass doors and partitions for high-end hotels, glass windows and many glass curtain walls use tempered glass. This is because the strength of the tempered glass is 3 to 5 times that of the flat glass, and it is also excellent in resistance to rapid cooling and rapid heat, and it is small in shape after being broken, and does not cause great damage to humans, so it is called safety glass. The production of tempered glass is very simple. After cutting, edging or punching the flat glass, it is sent to a tempering furnace above 650 °C for heating, and then quenched by cold blowing to form permanent compressive stress on the glass surface to make the strength. Greatly improved, this is tempered glass. Once the tempered glass is made, it can no longer be cut, otherwise it will be crushed.