Method for producing H-shaped steel
AssigneeNippon Steel Corporation
InventorHiroshi Yamashita
Life of this patent
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Abstract
A large-size H-shaped steel product is produced by performing a rough rolling step including an edging rolling step of rolling and shaping a material to be rolled into a predetermined almost dog-bone shape, and a flat rolling step of performing rolling of a web part by rotating the material to be rolled after completion of the edging rolling step by 90° or 270°, upper and lower caliber rolls of at least one caliber of calibers configured to perform the flat rolling step include recessed parts configured to form a raised part at a middle of a web part of the material to be rolled, the recessed parts being provided at roll barrel length middle parts of the upper and lower caliber rolls.
Claims4
A method for producing H-shaped steel, the method comprising:
- a rough rolling step;
- an intermediate rolling step;
- and
- a finish rolling step,
- wherein:
- a rectangular cross-section slab having a thickness of 290 mm or more and 310 mm or less is used as a raw material;
- the rough rolling step comprises:
- an edging rolling step of rolling and shaping the material into a predetermined shape including a web part;
- and
- a flat rolling step of rotating the material after completion of the edging rolling step by 90 degrees or 270 degrees and performing rolling of the web part of the material;
- the flat rolling step further comprising forming a raised part at a middle of the web part of the material using recessed parts of upper and lower caliber rolls having of at least one caliber of a plurality of calibers, each of the recessed parts being provided at respective middle parts along a respective roll barrel of the upper and lower caliber rolls;
- a width of the raised part formed in the flat rolling step is set to 25% or more and 50% or less of a width of the web part of the material;
- and
- a thickness of the web part rolled in the flat rolling step is set to a predetermined thickness in a range of values, a lower limit value of the range of values of the predetermined thickness being expressed by the following formula (3),
- Y=−0.118X2+11.732X−121.15 (3)
- where Y indicates the web thickness (mm) of the web part rolled in the flat rolling step, and X indicates an escaping percentage (%) equaling (width of the raised part L1/the width of the web part L2)×100.
Dependencies are inferred from the claim text.