it is in a tin bath, and the glass floats on the surface of the tin liquid. Therefore, this kind of glass is first of all smooth and has no water ripples.
used for making mirrors and automobile glass. No hair, no distortion, which is one of its great advantages.
Secondly, the quartz sand used for float glass is of good raw material. The produced glass is pure and transparent. Bright and colorless. There are no glass boils, bubbles and the like.
thirdly, the structure is compact, heavy, smooth to the touch, and the same thickness is larger than that of a flat plate per square meter, so it is easy to cut and not easy to be damaged.
More than 3 production lines in China are produced in strict accordance with national standards, and this kind of glass is the best glass for civil buildings. Its price, compared with the same thickness, is only about 4 yuan higher than that of flat glass per square meter.
production process:
the forming process of float glass production is completed in a tin bath filled with protective gases (N2 and H2). Molten glass continuously flows in from the tank kiln and floats on the surface of tin liquid with relatively high density. Under the action of gravity and surface tension, the glass liquid is spread and leveled on the tin liquid surface, and the upper and lower surfaces are flat, hardened and cooled before being led to the transition roller table. The rollers of the roller table rotate to pull the glass ribbon out of the tin bath into the annealing kiln, and after annealing and cutting, the flat glass product is obtained. Compared with other molding methods, the advantages of float method are: it is suitable for manufacturing high-quality flat glass with high efficiency, such as no ribs, uniform thickness, flat upper and lower surfaces and parallel to each other; The scale of the production line is not limited by the forming method, and the energy consumption per unit product is low; High utilization rate of finished products; Easy to manage scientifically and realize mechanization and automation of the whole line, with high labor productivity; The continuous operation cycle can be as long as several years, which is beneficial to stable production; It can provide suitable conditions for online production of some new varieties, such as electro-flotation reflective glass, spraying film glass during annealing, cold end surface treatment and so on.
what's the difference between ordinary flat glass and float glass
A: ordinary flat glass and float glass are both flat glass. Only the production process and quality are different.
Ordinary flat glass is a transparent five-color flat glass made of Shi Ying sandstone powder, silica sand, potassium fossils, soda ash, mirabilite and other raw materials in a certain proportion, which is melted in a furnace at high temperature and produced by vertical pull-up method or flat pull method and calendering method. Ordinary flat glass can be divided into three categories according to its appearance quality: selected products, first-class products and second-class products. According to the thickness, it is divided into five types: 2, 3, 4, 5 and 6mm.
B: Float glass is a transparent five-color flat glass made of raw materials such as sea sand, Shi Ying sandstone powder, soda ash, dolomite, etc., which are melted in a furnace at high temperature, and the glass liquid continuously flows from the tank furnace to float on the metal surface, spread into a glass ribbon with uniform thickness and polished by fire, cooled and hardened, separated from the metal liquid, and then annealed and cut. The glass surface is particularly flat and smooth, with very uniform thickness and little optical distortion. Float glass can be divided into three categories according to its appearance quality: superior product, first-class product and qualified product. According to the thickness, it can be divided into seven types: 3, 4, 5, 6, 8, 1 and 12 mm.
C: the appearance quality grade of ordinary flat glass is judged according to the number of defects such as wave ribs, bubbles, scratches, sand grains, bumps and lines. The appearance quality grade of float glass is judged according to the number of defects such as optical deformation, bubbles, inclusions, scratches, lines and fog spots.
< Raw materials of float glass >: Directory
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chapter 1 raw materials and glass composition
1? 1 overview
1? 2 composition of float glass
1? 2? 1 the role of oxides
glass definition-glass: a relatively transparent solid substance, which forms a continuous network structure when melting, and the viscosity gradually increases and hardens without crystallization during cooling. The chemical oxide composition of ordinary glass (Na2O·CaO·6SiO2) is mainly composed of silicon dioxide. Widely used in buildings to block wind and light.
China, also known as colored glaze in ancient times, is a kind of transparent, high strength and hardness, airtight material. Glass is chemically inert in the daily environment and will not interact with living things, so it is widely used. Glass is generally insoluble in acid (except that hydrofluoric acid reacts with glass to form SiF4, which leads to the corrosion of glass); But soluble in strong base, such as cesium hydroxide. Glass is an amorphous supercooled liquid. The melted glass cools rapidly, and each molecule forms glass because there is not enough time to form crystals.