Low-expansion heat-resistant fire-resistant glass, by weight percentage, which includes the following components: SiO2 75 ~ 85%, B2O3 8 ~ 19%, Al2O3 1 ~ 5%, Na2O 2 ~ 5.5%, K2O 0 ~ 3%, ZrO2 0 ~ 3%, ZnO 0 ~ 3%, MgO 0 ~ 3.5%, CaO 0 ~ 4%. Identified in this invention the glass composition, its glass products in 25 ℃ ~ 300 ℃ temperature range, thermal expansion coefficient significantly lower than the current flat glass, is located 3.1 × 10-7 / ℃ ~ 4.0 × 10-7 / ℃ between the Ritter softening point reached 820 ℃ and above, there is a very good heat resistance, heat a long time will not burst and softening deformation, can effectively extend the refractory time, stop the spread of fire and reduce losses. In blocking the spread of fire and fire-resistant glass composite rather, softening temperature, thermal expansion coefficient is small, light weight per unit area can be used to float glass production line for mass production.
