ALLOY CAST STEEL ROLLS

Characteristics : Carbon content in Alloy Cast Steel Rolls is in the range of 0.50% to 0.80%. These Hypo-eutectoid steel rolls are alloyed with Chromium and Molybdenum. The heat treatment of these rolls involve double annealing cycles followed by tempering. This helps to improve toughness and thermal shock resistance. The microstructure is primarily fine pearlitic with broken/spheroidized cementite. These rolls have high mechanical strength with good weldability.

Applications : These rolls are ideally suited for Blooming Mills and Roughing Stands for Light and Heavy Section Mills.

• Common Grades:
• ACS 33 (30°-35° Sh C)
• ACS 37 (35°-40° Sh C)

• Mechanical Properties:
• Tensile Strength : 700-800 N/mm2
• Bending Strength: 3-6 J/cm2

ALLOY STEEL BASE (ADAMITE) ROLLS

Characteristics : Alloy Steel Base Adamite Rolls are Hyper-eutectoid Steel alloyed with Nickel, Chromium and Molybdenum with higher Carbon content, ranging from 0.80% to 2.00%. Vanadium is also added to achieve the desired microstructure. It has higher mechanical strength and thermal/wear resistance. The rolls undergo a multi-stage, high temperature heat treatment cycle which consists of Normalizing/Hardening followed by a tempering cycle. This gives the rolls a combination of hardness, toughness and wear resistance required for a particular application. The microstructure consists of fine pearlitic matrix with spheroidized carbide.

Applications : These rolls are suitable for Roughing, Intermediate and Finishing stands for Section and Structural Mills. Applications include Heavy Section and Rail Mills, Universal Beam Mills, TMT Bar Mills, Medium Section Mills and Billet Mills.

• Common Grades:
• ADM 37 (35°-40° Sh C)
• ADM 42 (40°-45° Sh C)
• ADM 47 (45°-50° Sh C)
• ADM 50 (48°-52° Sh C)

• Mechanical Properties:
• Tensile Strength : 600-700 N/mm2
• Bending Strength: 3-8 J/cm2

GRAPHITE STEEL ROLLS:

Characteristics : This type of roll is special type of steel roll where some properties of cast iron must be included in the steel material. The service performance of this roll is superior to normal steel roll; it gives better wear resistance and resistance to fire cracking due to the presence of graphite without reduction of strength and toughness. Ideal for all mills like medium and heavy section where fire cracking is major concern.

• Common Grades:
• GPH 50 (48° - 52° Sh C)
• GPH 53 (53° - 58° Sh C)

SPHEROIDAL GRAPHITE IRON (PEARLITIC) ROLLS

Characteristics : Spheroidal Graphite Iron Rolls are structurally characterized as having graphite in nodular form instead of being in flakes as characterized in normal Cast Iron Rolls. The matrix structure varies from Ferrito-Pearlitic and Pearlitic together with different carbide content and graphite in the form of spheroid / nodules.

Applications : These rolls are suitable for Roughing and Intermediate Mill stands of Blooming/Slabbing, TMT Bars Mills and Wire Rod mills. Rolls for Intermediate and Finishing Stands of Structure and Strip Mills.

• Common Grades:
• SG P 47 (45°-50° Sh C)
• SG P 53 (50°-55° Sh C)
• SG P 57 (55°-60° Sh C)
• SG P 63 (60°-65° Sh C)

• Mechanical Properties:
• Tensile Strength :400-600 N/mm2
• Bending Strength: 2-4 J/cm2

SPHEROIDAL GRAPHITE IRON (BAINITIC/ACCICULAR) ROLLS

Characteristics : S.G.I. Bainitic/Accicular Rolls are stronger and more wear resistant than S.G.I. Pearlitic Rolls and are capable of much higher hardness. They are alloyed with a higher % of Nickel and Molybdenum than S.G.I Pearlitic and as a result, Accicular rolls have a bainitic matrix with increased carbide. The name of this material is based on its constituents of nodular graphite and carbides in an accicular (needle-like) bainitic matrix, also called Lower Bainitic. These Rolls are very suitable for a wide range of applications due to its hardness penetration, good wear and heat resistance. Intensive water cooling of rolls is necessary to ensure best performance.

Applications : These rolls are suitable for Intermediate and Finishing Mill stands for TMT Bar Mills, Rail and Structural mills. Rolls for Finishing Stands of Wire rod and Strip Mills.

• Common Grades:
• SG AC 63 (60°-65° Sh C)
• SG AC 67 (65°-70° Sh C)
• SG AC 73 (70°-75° Sh C)

• Mechanical Properties:
• Tensile Strength : 500-600 N/mm 2
• Bending Strength: 3-5 J/cm 2

ALLOYED INDEFINITE CHILL ROLLS (AIC)

Characteristics : Alloyed Indefinite Chill Rolls (AIC) have a matrix structure which varies from fine pearlitic to bainitic martensitic depending on the alloy addition. The desired hardness is achieved by changing the carbide to graphite balance with the help of the chemical composition. The presence of flake graphite makes the material resistant to fire cracking, spalling/chip-off and wear. Also, due to alloy addition, these rolls have a much better hardness penetration than clear chill and other cast iron rolls. Alloyed Indefinite Chill Rolls (AIC) are highly suitable for products where surface finish is very critical. Adequate water cooling of roll is required. Wide range of hardness/composition for a variety of applications is available to suit a particular mill stand.

Applications : Intermediate/Finishing stand of Wire Rod Mills, TMT Mills, Merchant Mills and Structural Mills. Finishing stand of Strip, Sheet and Flat rolling mills.

• Common Grades:
• AIC 57 (55°-60° Sh C)
• AIC 63 (60°-65° Sh C)
• AIC 67 (65°-70° Sh C)
• AIC 73 (70°-75° Sh C)
• Special Grades:
• SPIC (70°-80° Sh C)

• Mechanical Properties:
• Tensile Strength :200-300 N/mm 2
• Bending Strength: 1-1.8 J/cm 2

QUALITY CONTROL

Quality Control - an integral element
All the rolls are thoroughly inspected at various stages of production to ensure that the best quality product reaches our customers. Inspection is carried out by a team of dedicated Engineers using various metrological instruments. Firstly, Hardness is checked by Proceq Equotip Hardness tester at the roughing stage. Then, the roll is put through Non-Destructive Testing (NDT) to check for any internal flaws. After passing these tests, the rolls are sent for final machining. Lastly, final hardness is taken and rolls are measured to ensure everything is as per customer's drawings and specifications. Rolls are then packed as per Customer's specifications.