The linear expansion coefficient of G3.3 borosilicate glass is 3.3 0.1x10-6/k, which is a kind of glass which is based on sodium oxide (Na2O), boron oxide (B2o3) and Silica (SiO2). The content of boron and silicon in the glass is high, boron: 12.5~13.5%, Silicon: 78~80%, it is said that this kind of glass is high borosilicate glass. It belongs to Pyrex glass in boron silicate glass. Acid and alkali resistant water, excellent corrosion resistance, with good thermal stability, chemical stability and electrical properties, it has resistance to chemical erosion, thermal shock resistance, mechanical properties, withstand the high temperature characteristics. High Borosilicate glass (also known as hard glass), due to linear thermal expansion coefficient (3.3 0.1) x10-6/k, also known as "borosilicate glass 3.3". It is a low expansion rate, high temperature, high strength, high hardness, high transmittance and high chemical stability of special glass materials, because of its excellent performance, is widely used in solar, chemical, pharmaceutical packaging, Electric light, craft jewelry and other industries. Its good performance has been widely recognized all over the world, especially in the field of solar energy applications more widely, Germany, the United States and other developed countries have been widely promoted. Borosilicate glass 3.3 of the linear thermal expansion coefficient (3.3 0.1) x10-6/k, its main performance indicators are up to international ISO standards, with the United States Corning 7740 Materials, Germany Shaw Company's 50 materials are the same kind of material. Compared with universal glass, non-toxic side effects, its mechanical properties, thermal stability, water resistance, alkali resistance, acid and other properties greatly improved, can be widely used in chemical, aerospace, military, family, hospital and other fields, can be made into lamps, plates, telescope films, washing machine observation holes, microwave ovens, solar water heaters and other products, With good popularization value and social benefit, the appearance of this kind of glass in our country is another new revolution of basic material industry.