Rolls for every stand of the mill

The working surface shows a white, graphite-free structure of eutectic carbide and transformed austenite — a hard layer with excellent wear resistance. Flake graphite is embedded in a pearlite matrix containing about 0.08% combined carbon. Compared to grey iron, white chill iron has greater hardness, better wear resistance and high compressive strength, making excellent work rolls for two-, three- and four-high mills turning out high-grade ferrous and non-ferrous sheet, strip and sections.

Carbon content in the range of 0.50% to 1.20%. Heat treatment gives a spheroidised or fine pearlite matrix for high toughness, with small areas of carbide increasing wear resistance. Normal double annealing followed by a tempering cycle improves toughness and thermal shock resistance. The microstructure is primarily pearlitic with broken cementite — mechanical strength of a higher degree with good weldability.

A highly alloyed centrifuged shell as the working layer over a core of grey iron or SG iron, depending on mill requirements. The shell microstructure — carbide and graphite in a matrix progressing from pearlite and bainite through to martensite in harder grades — gives wear resistance controlled by proper dispersion of graphite and carbides. Compared to statically cast double poured rolls: less average hardness drop, a more uniform compact shell, and lower core alloy content imparting higher toughness.

Widely used for hot rolling in pre-roughing and roughing group stands, and at different positions in section mills. The material consists of carbides in a pearlitic matrix with carbon between 1.0 and 2.2%. Depending on primary requirements, a variety of grades with a series of carbon contents and alloying elements are used, matched to mill conditions of wear, strength and thermal cracking.

Multi-grade rolls tailored to mixed rolling schedules where a single stand sees varied sections and materials — composition and chill depth adjusted to the customer\u2019s pass design.

Forged rolls made with centre holes for heat treatment and inspection — specified primarily for work rolls, back-up rolls, auxiliary and special rolls. Typical composition 0.85 C, 0.30 Mn, 0.30 Si, 1.75 Cr, 0.10 V, with molybdenum added and chromium varied for specific characteristics. Cold rolling involves extremely high pressures, and forged rolls deliver the strength, quality and wear resistance it demands — preferred in non-ferrous hot mills over iron rolls for their higher bending strength and resistance to metal pickup.

SG (ductile) iron is one of the most versatile roll materials today, with greatly improved properties including tensile strength above 40 kg/mm² against 20–30 kg/mm² for cast iron. Specifically good for small section and flat rolling, and most suitable for heavier sections where added strength and depth of hardness are required. Stand-cast acicular SG iron is employed for special-purpose rolls such as pilger rolls.

Nodular acicular rolls widely used for hot rolling in intermediate, prefinishing and finishing group stands. The material consists of nodular graphite and carbides in a martensitic and bainitic matrix — more wear resistant than nodular pearlitic rolls. Standard and higher-alloyed variants are chosen per mill conditions, where wear resistance increases with hardness drop against standard grades for the type of groove or calibre.

A centrifugally cast shell of high speed steel over a tough core of SG iron or forged steel. The shell is alloyed with chromium, molybdenum, vanadium and tungsten (typically C 1.6–2.3%) and hardened to form very hard MC carbides in a tempered martensite matrix. This gives several times the wear life of indefinite chill or SGACC rolls, a stable roll surface through long campaigns, and good resistance to thermal cracking — used in intermediate and finishing stands of hot strip, bar and wire rod mills.

General-purpose metal rolls manufactured to customer specification for varied rolling and processing applications beyond the standard grades.