Physical properties
Brand	SK-32	SK-34	SK-35	SK-36	SK-38
Index
Refractoriness ℃	1730	1750	1770	1770	1790
bulk density g/cm3	2.15	2.2	2.3	2.35	2.52
Apparent porosity ≦%	24	24	23	23	23
Cold crushing strength ≧Mpa	30	35	40	45	65
Refractoriness under load (0.2MP) ℃	1350	1350	1400	1450	1550
Permanet liner change  1500℃ 2hrs%	+0.2to-0.2	+0.2to-0.2	+0.1to-0.4	+0.1to-0.4	+0.1to-0.4
Thermal expansion at 1000  ℃	0.5	0.5	0.5	0.5	0.5
Fe3O4%	1.96	1.93	1.9	1.87	2
Al2O3%  ≧	42	48	55	60	65
SiO2	48-50	46-48	41-44	37-40	27-30