Properties
The mechanical properties are improved due to the presence of chilled surface strcture and the change of pinetree-like structure. The hardness and type of matrix of roll depend on the conditions of application. The roll produced with centrifugal method basically eliminates the presence of graphite in its working layer while the core is made of nodular cast iron, increasing as a result, both the wear-resistance and breaking strength.

Chemical Analysis
Designation of rolls |
C |
Si |
Mn |
P |
S |
Ni |
Cr |
Mo |
NiCrMo chilled cast iron rolls (I) |
2.9/3.6 |
0.25/0.8 |
0.2/1.0 |
¡Ü0.4 |
¡Ü0.08 |
0.5/1.0 |
0.2/0.6 |
0.2/0.6 |
NiCrMo chilled cast iron rolls (II) |
2.9/3.6 |
0.25/0.8 |
0.2/1.0 |
¡Ü0.4 |
¡Ü0.08 |
1.0/2.0 |
0.3/1.2 |
0.2/0.6 |
NiCrMo chilled cast iron rolls (III) |
2.9/3.6 |
0.25/0.8 |
0.2/1.0 |
¡Ü0.4 |
¡Ü0.08 |
2.0/3.0 |
0.5/1.5 |
0.2/0.6 |
NiCrMo chilled cast iron rolls(IV) |
2.9/3.6 |
0.25/0.8 |
0.2/1.0 |
¡Ü0.4 |
¡Ü0.08 |
3.0/4.5 |
0.5/1.7 |
0.2/0.6 |
Physical Properties
Designation of rolls |
Barrel hardness (HSD) |
Neck hardness (HSD) |
Tensile strength (MPa) |
Depth of chilled lager |
200 |
200/250 |
250/300 |
300 |
NiCrMo chilled cast iron rolls (I) |
60~70 |
32~50 |
£¾150 |
12~25 |
15~30 |
17~35 |
20~45 |
NiCrMo chilled cast iron rolls (II) |
62~75 |
35~52 |
£¾150 |
12~25 |
15~30 |
17~35 |
20~45 |
NiCrMo chilled cast iron rolls (III) |
65~80 |
40~55 |
£¾150 |
12~25 |
15~30 |
17~35 |
20~45 |
NiCrMo chilled cast iron rolls(IV) |
70~85 |
32~45 |
£¾150 |
12~25 |
15~30 |
17~35 |
20~45 |
Microstructure
Designation of rolls |
Microstructure |
NiCrMo chilled cast iron rolls (I) |
Pearlite + cementite +ledeburite |
NiCrMo chilled cast iron rolls (II) |
Fine pearlite + cementite +ledeburite |
NiCrMo chilled cast iron rolls (III) |
Sorbite + cementite + ledeburite |
NiCrMo chilled cast iron rolls(IV) |
Sorbite + cementite + ledeburite |
Application
Designation of rolls |
Application |
NiCrMo chilled cast iron rolls (I) |
Section mill, bar mill, wire-rod mill narrow strip mill, finishing stand |
NiCrMo chilled cast iron rolls (II) |
Section mill, bar mill, wire-rod mill narrow strip mill, finishing stand |
NiCrMo chilled cast iron rolls (III) |
Section mill, bar mill, wire-rod mill narrow strip mill, finishing stand, tube stretch reducing mill |
NiCrMo chilled cast iron rolls(IV) |
Section mill, bar mill, wire-rod mill narrow strip mill, finishing stand, tube stretch reducing mill | |