Silica ramming mass can safely be used up to an operating temperature of 1600 C. Since it expands very little, it is superior to both alumina and magnesia refractories to resist thermal shocks. Though silica lining has good endurance against thermal shock, it has poor resistance against steelmaking slags. Temperature control is very necessary for a satisfactory lining life.
Typical chemical composition of silica ramming mass consists of SiO2 – 98.9 % minimum, Al2O3 – 0.6 % maximum, Fe2O3 – 0.2 % maximum, and CaO – 0.1 % maximum. The typical physical properties of the silica ramming mass