The production process of glass mainly includes the following steps: raw material preparation, melting, molding, annealing and subsequent treatment. ‌

Raw material preparation

The main raw materials of glass include quartz sand (mainly silicon dioxide), soda ash (sodium carbonate), limestone (calcium carbonate), etc. These raw materials need to be crushed and mixed to form a batch. The uniformly mixed batch will be used in the subsequent melting process. ‌

Melting

The batch is sent to a high-temperature furnace for heating, usually at a temperature between 1500-1700℃. At high temperatures, the raw materials melt and react chemically to form a uniform glass liquid. During the melting process, the carbonate raw materials will decompose to produce carbon dioxide gas, which needs to be discharged through the exhaust system to avoid the formation of bubbles in the glass. ‌

Molding

The molten glass liquid is molded according to demand. Common molding methods include blowing, pressing, wire drawing, etc. For example, flat glass can be made by float process, while bottle glass is mostly made by blowing. The temperature of the molded glass products is still very high, and they need to be annealed to eliminate internal stress and prevent cracking during cooling. ‌

Annealing

The formed glass products need to be sent to the annealing kiln for annealing. The annealing kiln is a device with a gradually lowered temperature. By controlling the temperature gradient, the stress inside the glass products is gradually released and reaches a balanced state, thereby avoiding the occurrence of cracking.

Subsequent processing

The annealed glass products also need to undergo a series of subsequent treatments and processing to meet different usage requirements. These treatments include polishing, grinding, drilling, etching, screen printing, etc. to improve the surface finish, strength and decorative effect.

Quality control and packaging

Finally, the glass products after completing all processes need to be quality tested, including thickness, strength, transparency, etc., to ensure that the quality meets the standards before packaging and shipment.