What is the Manufacturing Process of Tempered Glass

31 Jul.,2025

Uncover the fascinating process behind tempered glass, a vital material renowned for its exceptional strength and safety features. Dive into the sophisticated heating and cooling techniques that bolster its durability, rendering it perfect for multiple applications. Join us as we explore each step in crafting this high-performance glass and discover its transformative impact today!

 

 

Tempered glass, also called toughened glass or reinforced glass - belongs to safety glass. Tempered glass is actually a type of prestressed glass. In order to improve the strength of glass, chemical or physical methods are usually used to form compressive stress on the surface of the glass. When the tempered glass is subjected to external forces, it first offsets the surface stress, thereby improving the load-bearing capacity and enhancing the tempered glass's own resistance to wind pressure, cold and heat, impact resistance, etc. .

 

What is the Manufacturing Process of Tempered GlassWhat is the Manufacturing Process of Tempered Glass

 

Advantages of Tempered Glass

 

1. High safety.

The increased load-bearing capacity of tempered glass improves its fragile nature. When the tempered glass is damaged by external force, the fragments break into small obtuse-angle particles similar to honeycombs, reducing harm to the human body.

 

What is the Manufacturing Process of Tempered Glass

 

2. High intensity.

 

The impact strength of tempered glass of the same thickness is 3 to 5 times that of ordinary glass, its bending strength is 3 to 5 times that of ordinary glass, and its impact strength is 5 to 10 times that of ordinary glass.

 

3. Thermal stability.

Tempered glass has good thermal stability, and its resistance to rapid cooling and rapid heating is 2 to 3 times higher than that of ordinary glass. It can generally withstand temperature changes of more than 150LC, and has obvious effects on preventing thermal explosions.

 

Where Tempered Glass Product is Used:

 

1. Construction and decoration industry (for example: doors, windows, curtain walls, interior decoration, etc.)

2. Furniture manufacturing industry (glass coffee table, furniture accessories, etc.)

3. Home appliance manufacturing industry (TVs, ovens, air conditioners, refrigerators, etc.)

4. Electronics and instrumentation industry (mobile phones, MP3, MP4, clocks and other digital products)

5. Automobile manufacturing industry (automotive windshields, etc.)

6. Daily products industry (glass cutting boards, etc.)

7. Special industries (glass for military industry)

 

What is the Manufacturing Process of Tempered Glass What is the Manufacturing Process of Tempered Glass

 

 

Tempering Process of Tempered Glass Manufacturing

 

Tempered glass is made by heating the ordinary glass to close to the softening temperature (when it is in a viscous flow state) - this temperature range is called the tempering temperature range (620℃-640℃), keeping it warm for a certain period of time, and then cooling it suddenly. The following is a brief description of the temperature change and stress formation process of tempered glass during heating and quenching.

 

a. Phase to Start Heating:

The glass piece enters the tempering furnace for heating at room temperature. Since glass is a poor conductor of heat, the temperature of the inner layer is low and the temperature of the outer layer is high. The outer layer begins to expand, but the inner layer does not expand. Therefore, the expansion of the outer layer is inhibited by the inner layer, causing temporary compressive stress on the surface. , the central layer is tensile stress. Due to the high compression resistance of glass, the glass pieces will not break despite rapid heating. (Note: From here we can learn that once the glass enters the furnace, the temperature difference between the inner and outer layers of the glass causes stress on the inner and outer layers of the glass. Therefore, thick glass should be heated slower and at a lower temperature. Otherwise, the temperature difference between the inside and outside is too large and the glass will be in the furnace. rupture inside.)

 

b. Phase to Continue the Heating:

As the glass continues to heat, the temperature difference between the inner and outer layers of the glass shrinks, and when both the inner and outer layers reach the tempering temperature, the stress in the glass plate is equal.

 

c. Phase to Start the Quenching (1.5-2 seconds before starting to blow):

The glass sheet enters the air grille from the tempering furnace and is blown. The temperature of the surface layer drops below the core temperature, and the surface begins to shrink, while the central layer does not shrink. Therefore, the shrinkage of the glass surface layer is inhibited by the central layer, causing the surface layer to be subject to temporary tensile stress. The central layer Create compressive stress.

 

d. Phase to Continue the Quenching:

The inner and outer layers of the glass are further quenched, and the surface layer of the glass has hardened (the temperature has dropped below 500°C) and stopped shrinking. At this time, the inner layer also begins to cool and shrink, and the hardened surface layer inhibits the shrinkage of the inner layer. As a result, compressive stress is generated in the surface layer, and tensile stress is formed in the inner layer.

 

e. Phase to Continue Quenching (within 12 seconds):

The temperature of the inner and outer layers of glass further decreases. At this time, the inner layer of glass drops to about 500°C, and the shrinkage accelerates. At this stage, the compressive stress of the outer layer and the tensile stress of the inner layer have basically formed. However, the central layer is still relatively soft and has not completely escaped from the viscous flow state, so it is not the final stress state.

 

f. Tempering Completed (within 20 seconds):

At this stage, both the inner and outer layers of glass are completely tempered, the temperature difference between the inner and outer layers is reduced, and the final stress of the tempered glass is formed, that is, the outer surface is compressive stress and the inner layer is tensile stress.

 

Continuous Tempering Furnace to Heat and Cool Tempered Glass

 

What is the Manufacturing Process of Tempered Glass

 

 

About Huide Glass: 

 

Huide Glass has been in that processing business of tempered glass sheets products for around 13 Years since 2011. We have strong production and development capabilities, and currently has 7 automatic cutting machines, 8 edge grinding lines, there are 8 CNC precision grinding processing centers; there are 3 tempering furnaces(one for North-Glass, one for Yihai, and one for continuous tempering furnace SOUTHTECH). we can fabricate tempered glass sheet products 3,000,000 square meter per year. 

 

Our tempered glass products includes tempered glass shelf for refrigerator, tempered glass door for refrigerators, tempered glass lid for household washing machines, tempered glass sheet for smart tea table top or bedside table top, tempered glass cover panel for water cleaner and water heater, tempered glass cover for advertising billboard, tempered glass top and front door panel for tea bar machine, tempered glass door sheet for ovens, tempered glass sheet for gas stoves, tempered glass cover panel for display cabinet, display box, or tempered glass cover sheet for showcase counter,etc, and also we can do customized manufacturing according to your unique real applications. if you want to know more, don't hesitate to contact us. 

 

 

What is the Manufacturing Process of Tempered Glass