Rolls

Hardness ：75+/-5

Material：High Nickel-Chromium-Aluminum Alloy

Sizes (Dia × Length, mm)：

711*1750

711*1500

600*1500

600*1250

600*1000

600*600

400*1500

400*800

Hardness ：75+/-5

Material：High Nickel-Chromium-Aluminum Alloy

Sizes (Dia × Length, mm)：

815*2135

800*1500

800*1250

800*1000

600*1250

600*1000

600*800

600*600

400*800

400*600

Hardness ：69+/-3

Material：Nickel-Chromium-Molybdenum Alloy

Sizes (Dia × Length, mm)：

305*1830

400*2100

400*1500

400*1250

400*1000

300*1250

300*1000

250*1250

250*1000

250*800

250*600

Starting point of production. Selected metallic charge materials for roll manufacture are charged into an electric furnace and melted using electrical energy. Furnace temperature, melting time and chemical uniformity are tightly controlled to obtain a homogeneous molten metal ready for subsequent forming.

During melting, small quantities of molten metal are extracted with dedicated samplers. These samples are used to verify that the chemical composition meets specification before casting proceeds.

The taken melt samples are analyzed by optical emission spectrometry to precisely determine elemental contents. Results are compared with target ranges; if deviations appear, furnace additions or adjustments are made to ensure consistent product quality.

Approved molten metal is poured into a rapidly rotating mold. Centrifugal force distributes the metal against the mold wall forming a dense, uniform roll shell (rough casting). This process enhances internal soundness and structural homogeneity.

The freshly cast roll blanks are transferred to a controlled storage area (rough casting warehouse) where environmental conditions prevent corrosion or mechanical damage while awaiting machining.

Initial mechanical machining removes surface allowances, risers or excess material from the casting to bring the roll blank closer to its design envelope and provide reference surfaces for precision operations.

Precision milling or cutting of keyways (key seats) on the roll (or shaft) to specified dimensions and tolerances, ensuring accurate fit and torque transmission in later assembly.

High-precision turning of the roll body to achieve required diameter, concentricity and low surface roughness, laying the foundation for later finishing steps.

Drilling of specified holes (e.g., for cooling, mounting, or instrumentation) with controlled position, diameter and depth using appropriate drilling equipment and tooling.

Additional turning to refine geometry and dimensions after prior operations, reducing remaining allowances and preparing surfaces for heat treatment or subsequent precision steps.

Assembly stage where the roll body is press-fitted with its spindle (roll neck/shaft) using hydraulic or mechanical presses to achieve a secure, interference-fit connection assuring operational stability.

Combined heat treatment (austenitizing, quenching, tempering) applied to the assembled roll neck region to enhance mechanical properties such as strength, toughness and wear resistance for service loads.

Precision enlargement and finishing of existing internal holes using a boring machine to achieve tight dimensional, geometric and surface finish requirements for proper fit and alignment.

Cylindrical (and/or face) grinding removes residual machining marks, corrects minor geometric errors, and produces a high-quality surface finish critical to rolled product quality and roll performance.

Machining or forming of specific grooves, flutes or pass profiles on the roll surface according to rolling process requirements to control material deformation and guidance during rolling.

Rotational testing to measure and correct imbalance. Mass adjustments (e.g., drilling, adding weights) are performed so the roll runs smoothly at operating speeds, minimizing vibration and noise, extending service life.

Comprehensive quality inspection covering dimensional accuracy, surface condition, internal integrity (e.g., NDT), and compliance with customer and standards requirements before release.

Measurement of surface and (where required) subsurface hardness using Rockwell, Brinell or other methods to verify that hardness values fall within specified design ranges ensuring performance.

Conforming rolls are protected with tailored wooden crating to prevent impact, abrasion and corrosion during handling, storage and transport, ensuring safe delivery to the customer.

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