Roll Manufacturing Processes
Roll Manufacturing Processes
Roll Manufacturing Process
About Our Roll Manufacturing Processes
We have realized an integrated in-house production framework involving all stages from raw material procurement through casting, processing, inspection, and shipping out.
We fully leverage casting and forging processes and apply precision machining to manufacture high-quality rolls for rolling mills. With our integrated in-house framework we deliver rolls for rolling mills optimized for the manufacturing conditions of our customers, who produce a diverse range of metal products.
Roll Main Process
Main Processes
Molding
A preparatory step for molds used in casting. We use two different types: sand molds for shaft sections requiring strength and metal molds (dies) for body sections that come in contact with steel materials in the course of rolling.
Equipment
Two molding sand mixers(as of April 2025)
Melting
A process employing induction furnaces to melt raw materials. The stage in which molten iron is produced. Strict control of factors such as raw materials, components, temperature, and timing is enacted, as this is an important process in determining the performance of finished products.
Equipment
One 30-t low-frequency induction furnace, one 15-t low-frequency induction furnace, two 3-t high-frequency induction furnaces, one emission spectrometer (as of April 2025)
Casting
The stage when molten iron is poured into molds. Proper control of factors such as the temperature and casting speed is enacted to ensure that no impurities remain in finished products.
Equipment
One horizontal centrifugal casting machine, one inclined centrifugal casting machine(as of April 2025)
Heat Treatment
The stage in which heat treatment is applied to enhance the performance of finished products. Our proprietary SIP (Sumitomo Improved Penetration) heat treatment is applied to enhance various performance factors by densifying the structure of the metal. For centrifugal high-speed steel, DH (Differential Heat treating), another proprietary heat treatment of our own, is applied to deliver increased hardness of body sections only.
Equipment
Seven heat treatment furnaces, one DH furnace (as of April 2025)
Processing
A processing, or machining, stage in which products are given finished forms. Skilled selection of specialized tools is performed in accordance with the hardness and other qualities of the material to carry out machining on the nanometer (μm) order.
Equipment
14 NC roll lathes, three cylindrical grinding machines, two horizontal boring machines, two five-face milling machines(as of April 2025)
Inspection
Intraoperation inspections are carried out before sending out finished products.
Only good-quality items satisfying specified specifications and criteria are allowed on to the next stage.
Inspection items
Dimension measurements, ultrasonic testing (introduction of automatic ultrasonic flaw detection testing equipment planned within 2025), magnetic particle testing, Shore D hardness testing, microstructure observation