item   

index   

RN-42

RN-40

RN-36

ω(Al₂O₃),%                    ≥

42

40

36

Bulk density,g/cm³  

2.00 2.20

2.00 2.20

2.00 2.20

Apparent porosity,%             ≤

22(24)

22(24)

22(24)

Compressive strength,MPa        ≥

35

30

25

refractoriness under load of 0.2MPa,    ≥

1410

1350

1300

Permanent linear change,%

1400×2h

0.40

1350×2h

0.50

0.50

Remarks1.the data in the parenthesis is for the checker brick in checker chamber

         2.bulk density index is the reference index of the designed brick, and dont used for assessment