Spheroidal Graphite Cast Iron Roll
Spheroidal Graphite Cast Iron Roll
Thanks to its higher content of Ni and Mo alloys, pearlite, basinite and martensite matrixes with excellent performance are produced. The graphite si spherical form, demonstraing good heat transfer property and high tensile strength. Through changing the struture into basinite of marensite matrix, chemical compostion of needly-like spherical iron of heat treatment, a dense reticular primary cementite with high wear-resistance is produced.
Figure 1. Centrifugal Figure 2. Static
Figure 3. Pearlitic Figure 3. Bainitic
Mechanical properties
|
Designation of rolls
|
Barrel hardness (HSD)
|
Neck hardness (HSD)
|
Tensile strength (MPa)
|
|
CrMo semi-chilled SG cast iron rolls
|
40~55
|
32~50
|
＞300
|
|
CrMo indefinite chilled SG cast iron rolls
|
55~70
|
35~55
|
＞300
|
|
NiCrMo indefinite chilled SG cast iron rolls (I)
|
48~70
|
35~55
|
＞320
|
|
NiCrMo indefinite chilled SG cast iron rolls (II)
|
48~70
|
35~55
|
＞320
|
|
Pearlitic nodular cast iron rolls (I)
|
45~55
|
35~55
|
＞450
|
|
Pearlitic nodular cast iron rolls (II)
|
55~65
|
35~55
|
＞450
|
|
Pearlitic nodular cast iron rolls (III) |
62~72 |
35~55 |
＞450 |
|
bainitic nodular cast iron rolls (I) |
55~78 |
32~45 |
＞350 |
|
bainitic nodular cast iron rolls (II) |
60~80 |
32~45 |
＞350 |
Chemical Properties
|
Designation of rolls
|
C
|
Si
|
Mn
|
P
|
S
|
Ni
|
Cr
|
Mo
|
Mg
|
|
CrMo semi-chilled SG cast iron rolls
|
2.9/3.6
|
0.8/2.5
|
0.4/1.2
|
≤0.25
|
≤0.03
|
0.2/0.6
|
0.2/0.6
|
＞0.04
|
|
|
CrMo indefinite chilled SG cast iron rolls
|
2.9/3.6
|
0.8/2.5
|
0.4/1.2
|
≤0.25
|
≤0.03
|
0.2/0.6
|
0.2/0.6
|
＞0.04
|
|
|
NiCrMo indefinite chilled SG cast iron rolls (I)
|
2.9/3.6
|
0.8/2.5
|
0.4/1.2
|
≤0.25
|
≤0.03
|
0.5/1.0
|
0.2/0.6
|
0.2/0.6
|
＞0.04
|
|
NiCrMo indefinite chilled SG cast iron rolls (II)
|
2.9/3.6
|
0.8/2.5
|
0.4/1.2
|
≤0.25
|
≤0.03
|
1.0/2.0
|
0.3/1.2
|
0.2/0.8
|
＞0.04
|
|
Pearlitic nodular cast iron rolls (I)
|
2.9/3.6
|
1.4/2.2
|
0.4/1.0
|
≤0.15
|
≤0.03
|
1.5/2.0
|
0.1/0.6
|
0.2/0.8
|
＞0.04
|
|
Pearlitic nodular cast iron rolls (II)
|
2.9/3.6
|
1.2/2.0
|
0.4/1.0
|
≤0.15
|
≤0.03
|
2.0/2.5
|
0.2/1.0
|
0.2/0.8
|
＞0.04
|
|
Pearlitic nodular cast iron rolls (III) |
2.9/3.6 |
1.0/2.0 |
0.4/1.0 |
≤0.15 |
≤0.03 |
2.5/3.0 |
0.2/1.2 |
0.2/0.8
|
＞0.04 |
|
bainitic nodular cast iron rolls (I) |
2.9/3.6 |
1.2/2.2 |
0.2/0.8 |
≤0.10 |
≤0.03 |
3.0/3.5 |
0.2/1.0
|
0.5/1.0 |
＞0.04 |
|
bainitic nodular cast iron rolls (II) |
2.9/3.6 |
1.2/2.0 |
0.2/0.8 |
≤0.10 |
≤0.03 |
3.5/4.5 |
0.3/1.5 |
0.5/1.0 |
＞0.04 |
Micro-structure
|
Designation of rolls
|
Microstructure
|
|
CrMo semi-chilled SG cast iron rolls
|
Pearlite + cementite + SG + small percentage fermite
|
|
CrMo indefinite chilled SG cast iron rolls
|
Pearlite + cementite + SG
|
|
NiCrMo indefinite chilled SG cast iron rolls (I)
|
Pearlite + cementite + SG
|
|
NiCrMo indefinite chilled SG cast iron rolls (II)
|
Fine pearlite + cementite + SG
|
|
Pearlitic nodular cast iron rolls (I)
|
pearlite + cementite + small percentage fermite
|
|
Pearlitic nodular cast iron rolls (II)
|
pearlite + cementite + small percentage fermite
|
|
Pearlitic nodular cast iron rolls (III) |
pearlite + cementite + small percentage fermite |
|
bainitic nodular cast iron rolls (I) |
bainite + cementite + SG
|
|
bainitic nodular cast iron rolls (II) |
bainite + cementite + SG
|
Application
|
Designation of rolls
|
Application
|
|
CrMo semi-chilled SG cast iron rolls
|
Section mill, bar mill, roughing stands of wire-rod mill, work roll of rail mill
|
|
CrMo indefinite chilled SG cast iron rolls
|
Section mill, bar mill, intermediate and finishing stands of wire-rod mill
|
|
NiCrMo indefinite chilled SG cast iron rolls (I)
|
Section mill, bar mill, intermediate and finishing stands of wire-rod mill
|
|
NiCrMo indefinite chilled SG cast iron rolls (II)
|
Section mill, bar mill, intermediate and finishing stands of wire-rod mill
|
|
Pearlitic nodular cast iron rolls (I)
|
roughing stands of bar mill and wire-rod mill
|
|
Pearlitic nodular cast iron rolls (II)
|
roughing stands of bar mill and wire-rod mill
|
|
Pearlitic nodular cast iron rolls (III) |
roughing stands of bar mill and wire-rod mill |
|
bainitic nodular cast iron rolls (I) |
roughing stands of bar mill and wire-rod mill |
|
bainitic nodular cast iron rolls (II) |
roughing stands of bar mill and wire-rod mill |