Indicator name

Index

Mass fraction per calcined substance at temperature (1000 + 50) ºС, %

• MgO, no less
• CaO, no more
• SiO₂, no more
• Fe₂O₃, no more

91,0

3,0

3,0

2,5

Open porosity, %, no more

22

Ultimate compressive strength, N/mm², not less

60

Starting temperature of softening, ºС, not lower

1550

Indicator name

Index

MgO, not less, %

65

65

Cr₂O₃, within, %

7-15

7-15

Ultimate compressive strength, N/mm² , not less

32,5

32,5

Open porosity, %, no more

20

20

Starting temperature of softening, ℃, not lower

1540

1540

Thermal resistance (heating up to 1300℃,

water cooling) number of heat cycles, not less

5

5

Additional linear shrinkage at 1650℃ with

exposure for 3 hours, %, no more

0,8

0,5

Indicator name

Index

MgO, not less, %

65

Cr₂O₃, within, %

8-18

Ultimate compressive strength, N/mm2² , not less

25

Open porosity, %, no more

24

Starting temperature of softening, ℃, not lower

1500

Thermal resistance, number of heat shifts, not less

8

Additional linear shrinkage at 1650℃ with exposure for 3 hours, %, no more

0,9

Indicator name

Index

Mass fraction, %

• MgO, no less
• C, within
• Al₂O₃, within

92

13–17

-

92

9–13

5-8

93

9–13

-

93

9–13

-

93

9–13

-

Open porosity, %, no more

3,0

3,0

3,0

3,0

3,0

Apparent density, g/cm3, no less

2,95

2,96

2,98

3,0

2,95

Compressive strength, N/mm², no less

30

35

35

30

30

Maximum application temperature, ºС

1850

1850

1850

1850

1850