Al2O 3 and MgO are added on the basis of SiO 2-cao-na2o ternary system, which is different from plate glass in that the content of Al2O 3 is higher and the content of CaO is higher, while the content of MgO is lower.
No matter what type of molding equipment, whether it is beer bottles, liquor bottles, cans can be used this type of ingredients, only need to do some fine-tuning according to the actual situation. Its composition (mass fraction) range is: SiO 27%~73%, A12O 32%~5%, CaO 7.5%~9.5%, MgO 1.5%~3%, R2O 13.5%~14.5%.
This type of ingredient is characterized by a moderate aluminum content, the use of Al2O3 containing silica sand, or the introduction of alkali metal oxides with feldspar to save costs. The amount of CaO+MgO is relatively high, and the hardening speed is relatively fast, so as to adapt to the higher machine speed, a part of MgO is used instead of CaO to prevent the glass from crystallizing in the liquid flow hole, feeding passage and feeding machine. Moderate Al2O3 can improve the mechanical strength and chemical stability of glass.