Material

SiO2 :30~40% ;AI2O3:55~65%; R2O:~2%;RO :4~8%

Compression strength

>100kg/cm2

2kg softening point under load

1350C

Refractoriness 

1750C

The max temperature

1300C

Material:

SiC:55~70%;AI2O3+TiO3:13~15%;SiO2:18~22%;Fe2O3:1~1.5%
K2O.Na2O.CaO.MgO:0.5~1%

Compression strength

>400kg/cm2

2kg softening point under load

>1600C

Refractoriness

1650C

Apparent porosity

<18.2~24%

Reheating linear shrinkage

<0.5%