Specification :

Centrifugal Casting Acicular Spheroidal Graphite Rolls (mill rolls)

::Application
Various types of continuous rough intermediate and finish mills for processing bars, sections and strips. Used as

the secondary finishing and back rolls. Also suitable for use on stainless-steel strip hot mills.
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::Description
This grade is stronger and more wear resistant than SG Pearlitic iron and capable of much higher hardness levels.

The enhanced properties are the result of increased Nickel,Chromium and Molybdenum alloys.It also has 3% to 3.4%

carbon content alloyed with the nickel, manganese and molybdenum which forms the nodular cast iron with a bainitic-

acicular-martensitic matrix.non-continuous carbides maintain the wear resistance while at the same time exhibiting

high strength and resistance to firecracks. All rolls are specially molded and the final portion of the extensive

heat treatment procedure develops an acicular matrix.A special grade has been introduced:SGA grades alloyed with Cr

to achieve a deep penetration of carbides. These grades have a lower hardness drop, better wear resistance

properties, and is recommended for rolls with deep grooves.

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::Properties
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

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Mechanical Properties Centrifugal Method Conventional
Hardness of roll surface HSD50-85 HSD45-80
Hardness of roll collar HSD35-48 HSD35-55
Tensile strength of core e400MPa e300MPa
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::Chemical Composition of shell
C Si Mn Ni Cr Mo Mg
3.0/3.5 1.5/2.0 0.4/1.0 3.0/4.5 0.2/1.2 0.6/1.0 e0.04
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