Section Sleeves

Alloy Cast Steel rolls have a lower carbon content range than Steel Base qualities. The matrix can be heat treated to give either a spheroidised pearlite, which gives an alloy of maximum toughness, or a fine pearlite for additional wear resistance. There are also small areas of primary carbide (hype reutectoid) which enhance wear resistance. However, the most important characteristic of this type of roll is its high strength and toughness, and therefore it is primarily used in roughing and semiroughing applications.

SPECIFICATIONS

Production Type Static Monobloc Cast Materials

Chemical C  0.8-1.4 | Si 0.2-0.6 | Mn 0.5-1.8 | P ≤0.05 | S ≤0.05 | Ni ≤1.0 | Cr 0.45-1.20 | Mo 0.2-0.45

Hardness 35-50 HSc | Tensile ≥ 650-740 Mpa | Bending ≥ 700-1100 Mpa

SG Acicular, alloyed with the Nickel, Manganese and Chromium with a Bainitic-Acicular-Martensitic matrix has a higher UTS, hardness and is more wear resistant than the SG Pearlitic quality. Semi- continuous carbides maintain the wear resistance while at the same time exhibiting high strength and resistance to firecracks. Extensive heat treatment procedure ensures an acicular matrix. This grade can be produced by Static casting (Monoblock) or using the Centrifugal Cast (CC) Double pour method.

SG Acicular grades alloyed with Chromium 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.

SPECIFICATIONS

Production Type Static Monobloc or Centrifugal Cast Double Pour Materials

Chemical C  3.00-3.50 | Si 1.00-2.20 | Mn 0.30-1.00 | Ni 2.50-5.00 | Cr 0.30-1.50 | Mo 0.30-1.00

Hardness 61-78 HSc | Tensile ≥ 400-500 Mpa | Bending ≥ 600-750 Mpa

Graphitic Steel roll is the inclusion of spheroidal type graphite in a pearlitic, steel-like matrix. Consequently, it can be classified between nodular cast iron and hypereutectoid cast steel. This free graphite in the microstructure gives “iron-like” roll finish and increases the roll bite. This graphite permits self-lubrication to reduce side wear and also dissipates heat to reduce thermal cracking. With excellent penetration of hardness, this quality is suitable for all types of section mills.

SPECIFICATIONS

Production Type Static Monobloc Cast Materials

Chemical C  1.3-1.5 | Si 1.2-2.0 | Mn 0.8-1.1 | P – | S – | Ni 0.6-1.3 | Cr 0.2-0.8 | Mo 0.2-0.6

Hardness 35-50 HSc | Tensile ≥ 390-490 Mpa | Bending ≥ 490-686 Mpa

SG Pearlitic is characterised by nodular graphite and carbides arranged in a pearlitic matrix. Its properties are similar to Alloy Indefinite Chill except the graphite structure is changed from flake shapes to spheroidal forms. SG Pearlitic rolls will have higher strength than Indefinite Chill. SG Pearlitic rolls are suitable both roughing and finishing, and a wide range of applications. This grade can be produced by Static casting (Monoblock) or using the Centrifugal Cast (CC) Double pour method. In addition various SG Pearlitic grades have been introduced:

SGP grades alloyed with Chromium to achieve a deep penetration of carbides. These grades have a lower hardness drop and good wear resistance properties and is recommended for rolls with deep grooves.

SGP grades alloyed with Molybdenum and Nickel subjected to high temperature heat treatment have an excellent resistance to fire cracking properties along with high strength. The impact resistance is also increased over that of flake graphite iron.

SPECIFICATIONS

Production Type Static Monobloc or Centrifugal Cast Double Pour Materials

Chemical C  3.00-3.40 | Si 1.00-2.00 | Mn 0.30-0.80 | Ni 1.00-2.60 | Cr 0.10-0.90 | Mo 0.30-0.80

Hardness 40-65 HSc | Tensile ≥ 400-600 Mpa | Bending ≥ 600-900 Mpa

Adamite Steel Base rolls can be classified as high carbon alloy steel rolls. The carbon content is in the range 1.3-2.2% and alloy additions produce a structure containing no free carbon and a discontinuous hypereutectic carbide phase. However, for an increase in carbide there will be a reduction in toughness. The semi-continuous hypereutectic carbide in the microstructure will markedly increase the wear resistance of the material. Appropriate heat treatment gives this roll an excellent combination of hardness and strength, and the uniform hardness throughout the roll is ideal for deep, heavy sections.

SPECIFICATIONS

Production Type Static Monobloc Cast Materials

Chemical C  1.8-2.2 | Si 0.3-0.6 | Mn 0.7-1.1 | P ≤0.05 | S ≤0.05 | Ni ≤1.0 | Cr ≤ 2.0 | Mo ≤ 0.2

Hardness 40-50 HSc | Tensile ≥ 450-500 Mpa | Bending ≥ 508-755 Mpa

Alloy Indefinite Chill rolls consist of cast iron with fine interdendritic graphite evenly dispersed throughout the barrel of the roll. The size, shape and distribution of the graphite together with the carbide content is controlled by the chilling effect and the alloy content. The addition of alloys such as manganese, nickel, chromium, and molybdenum changes the matrix structure from pearlitic, through bainite, to martensitic. The carbide form is altered from semi-continuous to rigid continuity enhancing the strength, hardness in depth and wear resistance properties.

The fine graphite enhances the resistance to the thermal stresses by increasing the thermal conductivity, thus reducing fire cracks. Its increased shock resistance (damping capacity) helps to reduce spalling particularly when large reductions in section are required.

The gradual change in hardness makes it ideal for deeper grooving and can be used in both roughing and finishing stands for bar and sections, and for roughing and intermediate stands of wire and rod mills. AIC rolls with artensitic structure and high hardness are suitable for finishing stands of wire mills. This grade can be produced by Static casting (Monoblock) or using the Centrifugal Cast (CC) Double pour method.

SPECIFICATIONS

Production Type Static Monobloc or Centrifugal Cast Double Pour Materials

Chemical C  3.00-3.50 | Si 0.60-1.20 | Mn 0.50-1.20 | Ni 1.00-5.00 | Cr 0.70-2.00 | Mo 0.10-0.50

Hardness 51-85 HSc | Tensile ≥ 380-500 Mpa | Bending ≥ 580-700 Mpa