Low porosity fire clay brick is specially made from flint clay 45%,and the particle size of the raw material is strictly limited.The apparent porosity of the brick and reach 10 g/cm3.As it's rather dense,it has good performance under high temperature.It has good resistant to alkli slag and its refractoriness under load is high.The reheating linear Change is even better than high alumina bricks.As a kind of developed product,low porosity fire clay brick is widely used on iron&steel,glass,cement,chemical and non-ferrous metallurgy industrial.