Production Technology of Glass Bottle

 Production Technology of Glass Bottle

The production process of glass includes: batching, melting, forming, annealing and other processes. The introduction is as follows:

Firstly, weighing all kinds of raw materials in a mixer mixed evenly after ingredients according to the design of the material recipe.The main raw materials of glass are quartz sand, limestone, feldspar, soda, boric acid and so on.

Secondly, the prepared raw materials are melt through high temperature heating, forming a uniform bubble - free glass liquid.This is a very complex physical and chemical reaction process.The melting of glass takes place in the melting furnace, there are two main types of melting kilns. One is a crucible kiln, in which the glass material is held inside the crucible and heated outside the crucible.Small crucible kiln only put one crucible, large crucible can be up to 20 pieces.The other one is the pool kiln, in which the glass is melted and the open flame is heated on the surface of the glass.Most of the glass melting temperature is in 1300 ~ 1600 ℃. Most are heated by flame, but a small amount by electric current, called an electric furnace. Now, the pool kiln is continuous production, the small pool kiln can be several meters, the big can be more than 400 meters.

Thirdly, forming is to transform the molten glass into a solid product with a fixed shape. Forming can only be carried out in a certain temperature range, which is a cooling process. Glass first changes from viscous liquid to plastic state, then to brittle solid state. Forming methods can be divided into artificial forming and mechanical forming.

Lastly,  the glass undergoes intense temperature change and shape change during the forming process, which leaves thermal stress in the glass. This thermal stress will reduce the strength and thermal stability of glass products. If it is cooled directly, it is likely to crack during cooling or later storage, transportation and use. In order to eliminate cold explosion, glass products must be annealed after forming. Annealing is to keep the temperature in a certain range or cool down slowly for a period of time to eliminate or reduce the thermal stress in the glass to the allowable value.