Steel rolling mill roll  

 

1)Nodular cast iron rolls

 

Ductile iron with more Ni, Mo alloy can obtain good pearlite, bainite, martensite matrix organization, and graphite shape for the ball, good thermal conductivity, tensile strength, high by changing the organization as the bainite, martensite and needle ductile iron the chemical and heat treatment process, we can obtain very dense mesh primary cementite, improve abrasion resistance.

 

-- Mechanical Property

 

Rod surface hardness	HSD70-90
Core department hardness	HSD35-55
Core department tensile strength	>500Mpa

 

-- Application

 

Nodular cast iron rolls are mainly used in the billet and roughing stand of hot rolling mills;sections mills,tube mills,bar mills and wire mills.

 

 

-- Mechanical Property

 

Spheroidal Graphite Pearlitic Roll (SGPI)	60~70	35~55	>450
Spheroidal Graphite Pearlitic Roll (SGPII)	55~65	35~55	>450
Spheroidal Graphite Pearlitic Roll (SGPIII)	62~72	35~55	>450

 

 

 

 

 

 

 

3)Bainitic Nodular Cast Iron Rolls

 

Alloy elements of Ni ,Mn, Cr, Mo etc are added to bainitic nodular cast iron rolls for obtaining acicular(bainite-martensite)matrix in its microstructure of these rolls. Its strength and toughnes is higher than Perlitic Nodular Cast Iron Rolls, wearability is also better than latter. These rolls can be produced by static casting or centrifugal casting. 

 

Brand	C	Si	Mn	Cr	Ni	Mo
SGB 1	3.00-3.50	1.40-2.40	0.20-0.80	≤0.50	2.50-3.50	0.40-1.00
SGB 2	3.00-3.50	1.20-2.00	0.20-0.80	0.20-1.00	3.00-4.50	0.40-1.00

 

-- Mechanical Property

 

Brand	Barrel Hardness(HS)	Tensile Strength(Mpa)	Bending Strength(Mpa)	Application
SGB 1	55-70	≥400	600-800	Small profiled bar, stick, narrow steel finishing mill frame, high speed  wire pre-finishing rolling
SGB 2	62-80	≥400	600-800

 

 

 

 

 

 

 

4)Centrifugal Acicular nodular cast iron roll

 

Centrifugally Acicular nodular cast iron rolls(SGAI)	2.90~3.60	1.20~2.20	0.20~0.80	≤0.10	≤0.03	3.01~3.50	0.20~1.00	0.50~1.00
Centrifugally Acicular nodular cast iron rolls(SGAII)	2.90~3.60	1.00~2.00	0.20~0.80	≤0.10	≤0.03	3.51~4.50	0.30~1.50	0.50~1.00

 

-- Mechanical Property

 

Centrifugally Acicular nodular cast iron rolls(SGAI)	55~78	32~45	>350
Centrifugally Acicular nodular cast iron rolls(SGAII)	55~78	32~45	>350

 

 

 

 

 

5)Indefinite Chilled cast iron roll 

 

The feature of this casting roll is that it shaped into graphite ball and its performances can be compared with that of alloy infinite chilled roll, and its intensity is higher than that of infinite chilled one, so it is usually used for rest energy casting.

 

-- Chemical Composition

  

Grade	Hardness(HSD)	C	Si	Mn	Ni	Cr	Mo
Indefinite-I	60-70	3.0/3.5	0.5/1.0	0.5/1.0	0.5/1.0	0.5/1.0	0.2/0.6
Indefinite-II	62-72	3.0/3.5	0.5/1.0	0.5/1.0	1.0/2.0	0.5/1.0	0.2/0.6
Indefinite-III	65-75	3.0/3.5	0.5/1.0	0.5/1.0	2.0/3.0	0.7/1.2	0.2/0.6
Indefinite-IV	70-85	3.0/3.5	0.5/1.0	0.5/1.0	3.0/5.0	1.0/2.0	0.2/0.6

 

  

 

 

 

 

 

 -- Physical  properties

 

Hardness of shell	HSD60-85
Hardness of neck	HSD35-48
Tensile Strength of core	≥450Mpa

 

 

 

 

 -- Application Scope

 

 

For the finishing stands of continuous rolling mill of strip and bar, the pre-finishing stands of high speed wire, the intermediate and the front of finishing stands of small section, also utilized in thin plate and straightening roll.