Material Grade: SG II, SG IV, SG V

Section, Wire Rod & Narrow Strip Mill Indefinite Chilled Nodular Iron Rolls (SG Series)

Designed for intermediate rolling applications requiring a balance of toughness and wear resistance. The SG series utilizes a nodular iron base with an indefinite chill microstructure, providing the necessary bite friction and surface durability to support stable pass shapes in long product mills.

By Material

By Application

By Tooling

Key Mill Applications (Recommended Stands)

Wire Rod & Bar Mills

Recommended Grades: SG II, SG IV

Effective for intermediate stands. The graphite distribution helps to manage thermal stress, while the chilled matrix supports consistent pass life during continuous rolling operations.

Small Section Mills

Recommended Grades: SG IV, SG V

Offers stable performance for light section profiles. It helps to maintain surface quality and aids in preventing premature wear in the pass grooves under moderate loads.

Narrow Strip Mills

Recommended Grades: SG V

Suitable for intermediate stages where both structural integrity and moderate wear resistance are required to handle strip shape stability.

Chemical Composition & Physical Properties

We balance the nodularizing elements with alloying components to achieve a uniform distribution of graphite and carbides. The specific metallurgical parameters for the SG series are detailed below:

Code	C	Si	Mn	Cr	Ni	Mo	Hardness (HSD)	Tensile (N/mm²)
SG II	2.90-3.60	0.80-2.50	0.40-1.20	≤ 0.20	–	0.20-0.60	50-70	≥ 320
SG IV	2.90-3.60	0.80-2.50	0.40-1.20	0.20-0.60	0.50-1.00	0.20-0.80	55-70
SG V	2.90-3.60	0.80-2.50	0.40-1.20	0.30-0.80	1.01-2.00	0.20-0.80	60-70

Metallurgical Excellence

Why do DURON SG Series rolls support reliable intermediate rolling?

Thermal Shock Mitigation : The presence of spheroidal graphite helps to dissipate heat and absorb thermal expansion during rolling cycles. This microstructural feature reduces the risk of deep fire crazing and surface deterioration.
Optimized Bite Friction : The specific surface characteristics of the indefinite chill structure promote reliable billet biting. This is essential for maintaining the rhythmic flow of the rolling line and reducing slippage.
Balanced Operational Reliability : With a tensile strength of ≥ 320 N/mm², these rolls provide a safe operational margin for intermediate stands subjected to fluctuating mechanical loads and varied reduction rates.

Manufacturing Control & Inspection

100% Non-Destructive Testing

Every roll undergoes rigorous Ultrasonic Testing (UT) at the working layer and bonding zone to eliminate internal voids and ensure structural integrity under heavy loads.

Precision CNC Machining

Roll necks and barrel profiles are machined using heavy-duty CNC equipment, strictly adhering to your drawing's dimensional and runout tolerances for perfect bearing fitment.

Metallurgical Verification

Chemical compositions are analyzed via spectrometer pre-pouring, and multi-point hardness mapping is conducted post-heat treatment to guarantee the specified hardness gradient.

Quality Traceability

All dispatched rolls are accompanied by a comprehensive inspection certificate, documenting chemical composition, hardness distribution, and UT reports.