Ordinary flat glass
Ordinary flat glass is a transparent five colored flat glass produced by mixing raw materials such as quartz sandstone powder, silica sand, potassium fossils, soda ash, and saltpeter in a certain proportion, melting them at high temperature in a melting furnace, and using vertical pulling method, flat pulling method, and rolling method. Ordinary flat glass is divided into three categories based on appearance quality: selected products, first-class products, and second-class products. Divided into five types based on thickness: 2, 3, 4, 5, and 6mm.
Float glass is a transparent five color flat glass made from raw materials such as sea sand, quartz sandstone powder, soda ash, dolomite, etc., prepared in a certain proportion, melted at high temperature in a melting furnace, and the glass liquid continuously flows from the tank furnace to float on the metal surface. It is spread into a glass strip with uniform thickness and polished by fire, cooled and hardened to separate from the metal liquid, and then annealed and cut. The glass surface is particularly flat and smooth, with a very uniform thickness and minimal optical distortion. Float glass is divided into three categories based on appearance quality: superior, first-class, and qualified. Divided by thickness into seven types: 3, 4, 5, 6, 8, 10, and 12mm.
The appearance quality grade of ordinary flat glass is determined based on the number of defects such as ripples, bubbles, scratches, sand particles, lumps, and lines. The appearance quality level of float glass is judged based on the number of defects such as optical deformation, bubbles, inclusions, scratches, streaks, and fog spots.
Float glass
The forming process of float production is completed in a tin bath filled with protective gases (N2 and H2). Molten glass flows continuously from the tank furnace and floats on the surface of the relatively dense tin liquid. Under the action of gravity and surface tension, the glass liquid spreads and flattens on the tin liquid surface, forming a smooth upper and lower surface. After hardening and cooling, it is led up to the transition roller platform. The rollers on the roller table rotate, pulling the glass ribbon out of the tin bath and into the annealing kiln. After annealing and cutting, flat glass products are obtained. Compared with other forming methods, float glass has the advantages of being suitable for high-efficiency manufacturing of high-quality flat glass, such as no wave 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 achieve full mechanization and automation, with high labor productivity; The continuous operation cycle can last for several years, which is conducive to stable production; Suitable conditions can be provided for online production of some new varieties, such as electric float reflective glass, spray coated glass during annealing, cold end surface treatment, etc.