Alloy chilled cast iron rolls (rings) are manufactured by utilizing the subcooling of the molten iron itself and the chilling effect of the mold surface, combined with the addition of Ni, Cr, and Mo alloying elements. The matrix structure of the working layer is essentially free of flake graphite, resulting in high hardness and excellent wear resistance.
Large-scale rolls can be produced using static composite casting, providing high hardness in the roll body and high toughness in the roll neck, demonstrating good thermal stability and accident resistance.
Chemical Composition (%)
Code
Material
C
Si
Mn
Cr
Ni
Mo
V
CC-1
Chilled Cast Iron
—
—
CC-2
Chilled Cast Iron
—
CC-3
Chilled Cast Iron
—
CC-4
Chilled Cast Iron/Composite
—
(0.1-0.3)
Physical Properties
Code
Body Hardness (HS)
Neck Hardness (HS)
Tensile Strength (MPa)
Chill Depth – Sections (≤Φ200)
Chill Depth – Sections (Φ201-250)
Chill Depth – Sections (Φ251-300)
Chill Depth – Sections (>Φ300)
Chill Depth – Plate (Thin)
Chill Depth – Plate (Medium)
CC-1
58-70
32-48
> 150
12-25
15-30
17-35
20-45
CC-2
62-75
35-52
> 150
12-25
15-30
17-35
20-45
CC-3
65-80
35-52
> 150(300)
12-25
15-30
17-35
20-45
CC-4
60-70
35-48
> 300
8-35
8-45
Applications
CC-1: Finishing stands for small bar, wire rod, and narrow strip mills.
CC-2, CC-3: Finishing stands for small bar, wire rod, and narrow strip mills; sizing rings for seamless tube mills.
CC-4: Three-roll medium plate mills, hot-rolled stack thin plate mills.
Manufacturing Range
Small scale: Roll body diameter ≤Φ 550.
Large composite: Roll body diameter ≤Φ 900, body length 3000.
102 Alloy Indefinite Chilled Rolls
Alloy indefinite chilled rolls (rings) are distinguished from chilled cast iron rolls by the precipitation of fine graphite in the working layer. Graphite is uniformly dispersed throughout the roll cross-section, with its quantity and size increasing with depth. Due to the addition of Mn, Cr, Ni, Mo, and other alloying elements, the presence of fine graphite not only improves spalling resistance, thermal crack resistance, and wear resistance, but also ensures a small hardness drop in the working layer. Surface micro-graphite pores also improve the biting capacity of the roll.
Chemical Composition (%)
Code
Material
C
Si
Mn
Cr
Ni
Mo
IC-1
CrMo Indefinite
—
IC-2
NiCrMo Indefinite
IC-3
NiCrMo Indefinite
Physical Properties
Code
Body Hardness (HS)
Neck Hardness (HS)
Tensile Strength (MPa)
IC-1
58-70
35-55
> 160
IC-2
62-72
35-55
> 160
IC-3
68-75
35-55
> 160
Applications
IC-1: Intermediate and finishing stands for bar, wire rod, and section mills.
IC-2, IC-3: Intermediate and finishing stands for bar, wire rod, and section mills; sizing rings for seamless tube mills.
Manufacturing Range
Rolls: Body diameter ≤Φ 650, body length ≤ 1500.
Rings: Body diameter Φ190-600, body length 400(max.).
103 Alloy Spheroidal Graphite (SGP) Rolls
Alloy spheroidal graphite cast iron rolls (rings) are characterized by graphite in a nodular form within the matrix. By adjusting Ni, Cr, and Mo alloy elements and specific heat treatment regimes, different series such as common pearlite, large-scale alloy SG, pearlitic SG, and acicular SG rolls (rings) can be produced. These products offer good strength, high-temperature performance, and accident resistance, with minimal hardness drop in the working layer.
Chemical Composition (%)
Code
C
Si
Mn
Cr
Ni
Mo
Mg
SGP-1
—
≥0.04
SGP-2
≥0.04
SGP-3
≥0.04
SGP-4
≥0.04
SGAC
≥0.04
Physical Properties
Code
Body Hardness (HS)
Body Hardness Uniformity (HS)
Neck Hardness (HS)
Tensile Strength (MPa)
SGP-1
58-70
—
35-55
> 320
SGP-2
62-70
—
35-55
> 320
SGP-3
42-55
≤5
32-43
≥390
SGP-4
50-72
≤5
35-55
≥390
SGAC
55-75
≤5
40-60
≥400
Applications
SGP-1: Roughing and intermediate stands for bar, wire rod, and section mills; edging rolls for rail/beam mills.
SGP-2: Roughing and intermediate stands for bar, wire rod, and section mills.
SGP-3: Large blooming mills.
SGP-4: Roughing and intermediate stands for continuous section mills, bar/wire rod roughing/intermediate stands, and tube sizing rings.
SGAC: Intermediate and finishing stands for continuous section mills, seamless tube rolls/rings, and intermediate/pre-finishing/finishing stands for rebar/wire rod mills.
Manufacturing Range
Rolls: Suitable for various roll specifications.
Rings: Body diameter Φ190-1500, body length 900(max.).
104 High Ni-Cr Indefinite Chilled Composite Rolls
High Ni-Cr indefinite chilled composite rolls are high-performance rolls manufactured via centrifugal or full-flushing methods. By increasing Ni, Cr, and Mo content, high micro-hardness of the structure and carbides is achieved. Combined with special heat treatment, a uniform, dense working layer with small hardness drop is obtained. The presence of fine graphite provides good wear resistance, thermal crack resistance, spalling resistance, and indentation resistance. The outer layer thickness can be adjusted as needed, while the core utilizes tough gray iron or high-strength SG iron for satisfactory core and neck toughness. Sufficient water cooling during use is essential.
Physical Properties
Code
Hardness (HS)
Tensile Strength (MPa)
Bending Strength (HS)
Impact Toughness (×10⁴J/m²)
Elastic Modulus (kMPa)
HNiCr-1
70-85
350-450
450-650
3-7
150-190
HNiCr-2
60-75
350-450
450-650
2-6
150-190
Gray Core
35-50
> 190
350
3-7
110-150
SG Core
35-50
> 350
550
4-7
160-190
Applications
Finishing stand work rolls (rear stands) for hot strip mills.
Work rolls for roughing and finishing stands of wide/medium plate mills.
Work rolls and backup rolls for hot strip (plate) four-roll skin pass mills.
Cross-cut leveling rolls.
Steckel mill work rolls.
Pre-finishing rings for high-speed wire rod mills.
Work rolls for non-ferrous metal plate mills.
Manufacturing Range
Manufacturing Method
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Centrifugal
Φ280-1350
400-4300
45
Full-flushing
Φ800-1300
≤5500
105 High Chromium Composite Casting Rolls
High chromium composite rolls contain 6~22% chromium in the working layer with a high-strength SG iron core. Depending on carbon content, they are classified as high chromium cast steel or high chromium cast iron rolls. Due to high chromium, carbides are of the M7C3 type, providing high hardness, toughness, and wear resistance. The matrix is highly alloyed and specially heat treated for excellent high-temperature mechanical properties. They are used for hot strip mills based on stand position and cooling conditions. They are also applicable for cold mills, skin pass work rolls, and ring products.
Chemical Composition (%)
Code
Cr
HCr-1
10-15
HCr-2
14-19
HCr-3
16-21
HCrS
6-15
Physical Properties
Code
Hardness (HS)
Tensile Strength (MPa)
Bending Strength (HS)
Impact Toughness (×10⁴J/m²)
Elastic Modulus (kMPa)
HCr-1
60-70
500-800
700-1000
4-8
210-225
HCr-2
65-80
500-800
700-1000
4-8
210-225
HCr-3
78-92
600-900
900-1300
4-8
210-225
HCrS
65-85
700-1000
210-225
Roll Neck
35-50
> 350
550
4-7
160-190
Applications
HCr-1: Roughing work rolls for hot strip mills, work rolls for wide/medium plate mills.
HCr-2: Finishing stand work rolls (front stands) for hot strip mills, rolls for bar/wire mills and seamless tube straighteners.
HCr-3: Cold strip mill work rolls, skin pass work rolls.
HCrS: Roughing and front finishing work rolls for hot strip mills, cold strip mill work rolls, medium plate mill work rolls.
Manufacturing Range
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Φ280-1350
400-3100
35(max.)
201 Alloy Cast Steel Rolls
Alloy cast steel rolls are manufactured using electric arc and refining furnaces for high-quality steel, combined with advanced casting and heat treatment technologies, resulting in high strength, good thermal crack resistance, toughness, and wear resistance.
Chemical Composition (%)
Code
C
Si
Mn
Cr
Ni
Mo
V
CS-1
—
—
—
CS-2
—
CS-3
CS-4
CS-5
—
Physical Properties
Code
Body Hardness (HS)
Tensile Strength (MPa)
Elongation (%)
Impact Toughness (×10⁴J/m²)
CS-1
28-43
≥600
≥5
≥8
CS-2
30-45
≥800
≥5
≥8
CS-3
46-65
≥800
≥2
≥5
CS-4
45-65
≥800
≥3
≥4
CS-5
40-55
≥700
≥4
≥7
Applications
Square and slab blooming mills, section roughing/intermediate mills, hot strip mills, scale-breaker edging rolls, two-high roughing mills, medium plate two-high roughing mills, and backup rolls for hot-rolled narrow strip.
Manufacturing Range
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Φ1500(max.)
3000(max.)
60(max.)
202 Semi-steel Rolls
Semi-steel rolls include integral, composite, and sleeved products. Mo, Cr, Ni, and other micro-alloys are added to high-carbon steel, combined with special heat treatment. They offer high wear resistance, strong toughness, and good thermal crack resistance, with almost no hardness drop in the working layer.
Chemical Composition (%)
Code
C
Si
Mn
Cr
Ni
Mo
AD-1
AD-2
AD-3
AD-4
AD-5
Ring Core
≥1.50
≥1.20
—
—
—
—
Physical Properties
Code
Body Hardness (HS)
Tensile Strength (MPa)
Elongation (%)
Impact Toughness (×10⁴J/m²)
AD-1
35-50
≥500
≥1.0
≥4
AD-2
40-55
≥450
≥1.0
≥4
AD-3
50-65
≥350
≥0.5
≥5
AD-4
50-65
≥350
≥0.5
≥5
AD-5
45-55
≥350
≥0.5
≥5
Applications
Roughing stands, front finishing stands, and vertical rolls of hot strip mills; roughing, intermediate, and pre-finishing stands of section, rail/beam, and bar mills; rings and sleeves for universal and cantilever mills.
Manufacturing Range
Category
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Semi-steel Rolls
Φ1500(max.)
3000(max.)
60(max.)
Semi-steel Rolls
Φ1400(max.)
700(max.)
7(max.)
203 Graphite Steel Rolls
Graphite steel rolls exhibit performance similar to semi-steel rolls but are characterized by a small amount of graphite in the microstructure. Graphite improves thermal crack resistance and resistance to scale adhesion, making them suitable for blooming or roughing operations.
Chemical Composition (%)
Code
C
Si
Mn
Cr
Ni
Mo
GS-1
GS-2
GS-3
GS-4
GS-5
Core
<0.3
<1.0
—
Body Hardness
Code
GS-1
GS-2
GS-3
GS-4
GS-5
HS
36-44
38-55
40-48
42-50
44-52
Tensile Strength MPa: 385-750
Bending Strength MPa: 585-920
Applications
Roughing stands of hot strip mills and medium/wide plate two-high reversible mills.
Blooming mills, continuous billet mills, and section/rail/beam mills; particularly suitable for deep-groove rolls and hot strip mill roughing stands.
Manufacturing Range
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Φ1350(max.)
3100(max.)
50(max.)
204 Composite Cast Steel Backup Rolls
Cast steel backup rolls manufactured via composite casting. The outer layer contains Ni, Cr, Mo, and other alloys, specially heat-treated to a microstructure of tempered sorbite, bainite, and uniformly distributed fine carbides. The core and neck use high-quality low-carbon or low-alloy steel, providing high wear resistance, good spalling resistance, and strong toughness.
Chemical Composition (%)
Code
C
Si
Mn
Cr
Ni
Mo
DCS-1
DCS-2
DCS-3
DCS-4
Hardness (HS)
Code
DCS-1
DCS-2
DCS-3
DCS-4
Body
50-60
55-65
60-70
65-75
Neck
25-45
25-45
25-45
25-45
Mechanical Properties
Category
Body
Neck
Tensile Strength, MPa
1200-2000
min. 400
Yield Strength, MPa
1000-1400
min. 200
Body Hardness (HS)
FSC-1
FSC-2
FSC-3
FSC-4
FSC-5
FSC-6
FSC-7
FSC-8
FSC-9
FSC-10
60-70
60-80
76-80
60-80
60-70
65-75
75-85
77-85
65-71
80-95
90-100
90-100
90-100
90-100
65-80
90-100
90-100
86-90
75-82
Applications
Finishing stand work rolls for hot strip mills, cold strip mill work rolls, rings/sleeves for bar, wire, and universal H-beam mills.
Manufacturing Range
Category
Body Diameter (mm)
Body Length (mm)
Net Weight (t)
Rolls
Φ400-850
1000-2500
15(max.)
Rings
Φ200-1400
700(max.)
7(max.)
301 Forged Steel Cold Rolls
Forged steel cold rolls include cold work rolls and backup rolls. High-quality alloy forged steel blanks are produced using advanced smelting (EAF), refining (ESR and Ladle Refining), and forging equipment (3150t hydraulic press). Computer control ensures reproducibility of hardness and hardening depth. Specific heat treatments including induction hardening (continuous and integral), sub-zero treatment, and tempering produce a high, uniform hardness working layer with a depth exceeding 30mm, offering sufficient wear resistance, toughness, and accident resistance.
