Abstract: glass products are widely used in daily life. They are mainly made of glass. The raw materials for the production of glass products include sandstone, silica sand, feldspar, limestone, fluorite, soda ash, Glauber’s salt, various additives, etc. when producing glass in a glass factory, the raw materials are first classified and stored in the factory, and then the production can be completed after the raw material pre-processing, melting, forming, heat treatment, processing, inspection and other processes. Let’s learn about the raw materials and technological process of glass products.
1、 What raw materials are used to produce glass products
Glass products are produced from glass and are widely used in construction, daily use, medical treatment, chemistry and other fields. There are many raw materials for producing glass products, mainly including the following:
1. Sandstone: sedimentary rock formed by cementation of quartz (SiO2) particles.
2. Silica sand: natural sand mainly composed of quartz.
3. Feldspar: the general name of brick aluminate feldspar group minerals containing potassium, sodium and calcium.
4. Limestone: calcium carbonate rock.
5. Dolomite: double salt rock of calcium carbonate and magnesium carbonate.
6. Fluorite: natural mineral of calcium fluoride.
7. Soda ash: anhydrous sodium carbonate.
8. Mirabilite: anhydrous sodium sulfate.
9. Carbon powder: a powder mainly composed of carbon.
10.Additives: including flux inhibitor, clarifier, oxidizer, reductant, colorant, decolorizer, etc.
2、Brief introduction of glass product process
The production of glass products is usually carried out in glass factories. The production process varies according to different products and different raw materials. It can be roughly divided into the following steps:
1. Ingredients
After entering the factory, various raw materials for glass production shall be stacked by type.
2. Pre processing
The raw materials shall be pretreated, such as silica sand, soda ash, feldspar, dolomite, limestone, mirabilite, etc. shall be crushed, mixed and stirred according to the plan, and iron containing raw materials shall be removed.
3. Melting
The glass batch is heated at high temperature (1550-1600 ℃) in the tank furnace or tank furnace to form uniform, bubble free liquid glass that meets the forming requirements; The dirty material and glass liquid deposited at the bottom of the tank furnace flow out.
4. Forming
Put the liquid glass into the mold to make the glass products with the required shape. There are three types of molding: manual molding, mechanized molding and semi mechanized molding. The molding methods are usually blowing method, drawing method, pressing method and blowing pressing method.
5. Heat treatment
That is, annealing, quenching and other processes, mainly to reduce the thermal stress, phase separation or crystallization of glass products, and change the structural state of glass. The glass is heated to the temperature of strain point in the annealing furnace, and then cooled to room temperature at a certain rate.
6. Processing
It includes hot processing and cold processing. Hot processing includes hot cutting, hot sealing, modeling and other processes. Cold processing mainly includes polishing and grinding.
7. Inspection
The glass products processed according to the standard shall be inspected. The qualified products can be sold after packaging. The unqualified products shall be removed and the causes shall be found out.