Sk-36 ItemStandard Ai2o3(%)55 Fe2o3 (%)2.0 Refractoriness (sk)36 Refractoriness under load, 0.2mpa, ta, ((°c)1450 Porosity (%20-24 Bulk density (g/cm³)2.2-2.30 Cold crushing strength (mpa)45 Thermal expansion at 1000°c (%)0.3 Sk-38 ItemStandard Ai2o3(%)75 Fe2o3 (%)2.0 Refractoriness (sk)38 Refractoriness under load, 0.2mpa, ta, ((°c)1520 Porosity (%20-22 Bulk density (g/cm)2.4-2.5 Cold crushing strength (mpa)55 Thermal expansion at 1000°c (%)0.2.