Learn more about float glass

Glass is not necessarily very flat. The very flat glass you see is generally float glass. "Float" is a kind of technology. The origin, characteristics and production process of float glass are as follows:

Float glass is in a tin bath, the glass floats on the surface of liquid tin. Therefore, this kind of glass has good flatness and no water ripple. Used for mirror making and automobile glass. No face, no shape, this is one of its major advantages. The second is the ore quartz sand selected for float glass, with good raw materials. The glass produced is pure and transparent. It is bright and colorless. There's no glass, no bubbles and so on. Third, the structure is compact, heavy, smooth handle, the same thickness per square meter larger than the plate, good cutting, not easy to damage. More than 30 production lines in China are produced in strict accordance with national standards. This kind of glass is the best glass for civil buildings. Its price, compared with the same thickness, is only about 4 yuan per square meter of flat glass.

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 into the tank and floats on the surface of tin liquid with high relative density. Under the action of gravity and surface tension, the glass liquid spreads and flattens on the tin liquid surface, forms the upper and lower surface leveling, hardening and cooling, and then is led to the transition roller table. After annealing and cutting, flat glass products are obtained. Compared with other molding methods, float method has the following advantages: it is suitable for high-efficiency manufacturing of high-quality flat glass, such as no corrugated ribs, uniform thickness, smooth upper and lower surfaces, parallel to each other; the scale of production line is not limited by the forming method, the energy consumption per unit product is low; the utilization rate of finished products is high; it is easy to scientific management and realize the mechanization and automation of the whole line It can provide suitable conditions for on-line production of some new varieties, such as electro float reflective glass, spraying film glass during annealing, cold end surface treatment, etc.

What is 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 made of quartz sandstone powder, silica sand, potash fossil, soda ash, Glauber's salt and other raw materials according to a certain proportion, melted at high temperature in a furnace, and produced by vertical leading up method, flat drawing method and rolling method. According to the appearance quality, ordinary flat glass can be divided into three categories: special products, first-class products and second-class products. According to the thickness, it can be divided into 5 types: 2, 3, 4, 5 and 6 mm.

B: Float glass is made of sea sand, quartz sandstone powder, soda ash, dolomite and other raw materials according to a certain proportion. After melting at high temperature in the furnace, the glass liquid continuously flows from the tank to the metal surface and floats on the metal surface. After cooling and hardening, the float glass is separated from the liquid metal, and then annealed and cut. The glass surface is especially smooth, the thickness is very uniform, and the optical distortion is very small. According to the appearance quality, float glass can be divided into three categories: superior products, first-class products and qualified products. According to the thickness, it can be divided into 7 types: 3, 4, 5, 6, 8, 10 and 12 mm.

C: The appearance quality grade of ordinary flat glass is determined according to the number of defects such as ripple, bubble, scratch, sand, pimple and line. The appearance quality grade of float glass is judged according to the number of defects such as optical deformation, bubble, inclusion, scratch, line and fog spot.