The present invention relates to a method for producing H-shaped steel using a slab or the like having a rectangular cross-section as a material, for example. Provided is a method for producing H-shaped steel, the method including: a rough rolling step; an intermediate rolling step; and a finish rolling step. A slab material whose ratio of slab width to slab thickness is equal to or more than 6.0 and equal to or less than 7.7 is used as a material to be rolled. In a rolling mill a plurality of calibers having projections may be provided to shape the material to be rolled. The projections may have a height of 100 mm or more, and the tip of the projections may have an angle of equal to or more than 25 and equal to or less than 40.

A method for producing H-shaped steel, the method includes: a rough rolling step; an intermediate rolling step; and a finish rolling step, wherein: a rolling mill that performs the rough rolling step is engraved with a plurality of calibers configured to shape a material to be rolled; the plurality of calibers include: one or a plurality of split calibers formed with projections configured to create splits vertically with respect to a width direction of the material to be rolled to form divided parts at end parts of the material to be rolled; and a plurality of bending calibers formed with projections configured to come into contact with the splits and sequentially bend the divided parts formed by the split caliber; and the projections formed in a final split caliber of the split calibers are each composed a tip part in a tapered shape having a predetermined tip angle, and a base part located at a base of the tip part and having a tapered shape with a gentle inclination as compared with the tip part.

There are provided: an edging rolling step of rolling and shaping a material to be rolled into a predetermined shape; a raised part generating step of performing rolling of a web part by making the material to be rolled to be rotated, and forming a raised part at a middle of the web part of the material to be rolled; a supplementary edging rolling step of performing light reduction rolling by making the material to be rolled after being rolled in one pass or more in the raised part generating step to be rotated again and returning the material to be rolled to a final caliber in the edging rolling step; and a raised part eliminating step of reducing and eliminating the raised part formed in the raised part generating step, in upper and lower caliber rolls which perform the raised part generating step, recessed parts configured to form the raised part at the middle of the web part of the material to be rolled are provided at roll barrel length middle parts of the upper and lower caliber rolls, a roll shape of the upper and lower caliber rolls is designed to make tips of flange parts of the material to be rolled to be out of contact with the upper and lower caliber rolls, two steps of the raised part generating step and the supplementary edging rolling step are continuously performed one time or plural times, and the raised part eliminating step is performed after the raised part generating step and the supplementary edging rolling step are performed.

There are provided: an edging rolling step of rolling and shaping a material to be rolled into a predetermined shape; a raised part generating step of performing rolling of a web part by making the material to be rolled to be rotated, and forming a raised part at a middle of the web part of the material to be rolled; a supplementary edging rolling step of performing light reduction rolling by making the material to be rolled after being rolled in one pass or more in the raised part generating step to be rotated again and returning the material to be rolled to a final caliber in the edging rolling step; and a raised part eliminating step of reducing and eliminating the raised part formed in the raised part generating step, in upper and lower caliber rolls which perform the raised part generating step, recessed parts configured to form the raised part at the middle of the web part of the material to be rolled are provided at roll barrel length middle parts of the upper and lower caliber rolls, a roll shape of the upper and lower caliber rolls is designed to make tips of flange parts of the material to be rolled to be out of contact with the upper and lower caliber rolls, two steps of the raised part generating step and the supplementary edging rolling step are continuously performed one time or plural times, and the raised part eliminating step is performed after the raised part generating step and the supplementary edging rolling step are performed.

The present invention discloses a extra thick hot rolled H section steel and a production method therefor. The extra thick hot rolled H section steel contains, by mass, the following chemical components: 0.04-0.11% of C, 0.10-0.40% of Si, 0.40-1.00% of Mn, 0.40-1.00% of Cr, 0.10-0.40% of Cu, 0.020-0.060% of Nb, 0.040-0.100% of V, 0.010-0.025% of Ti, 0.010-0.030% of Al, 0.0060-0.0120% of N, not more than 0.015% of P, not more than 0.005% of S, not more than 0.0060% of O, and the balance Fe and trace residual elements, wherein 0.090%?Nb+V+Ti?0.170%, 6.5?(V+Ti)/N?10.5, and 0.30%?CEV?0.48%. The extra thick hot rolled H section steel has a flange thickness of 90 mm-150 mm, has excellent comprehensive mechanical properties, and can well meet the needs for heavy supporting structural parts of high-rise buildings, large squares, bridge structures, etc.

The present invention discloses a extra thick hot rolled H section steel and a production method therefor. The extra thick hot rolled H section steel contains, by mass, the following chemical components: 0.04-0.11% of C, 0.10-0.40% of Si, 0.40-1.00% of Mn, 0.40-1.00% of Cr, 0.10-0.40% of Cu, 0.020-0.060% of Nb, 0.040-0.100% of V, 0.010-0.025% of Ti, 0.010-0.030% of Al, 0.0060-0.0120% of N, not more than 0.015% of P, not more than 0.005% of S, not more than 0.0060% of O, and the balance Fe and trace residual elements, wherein 0.090%?Nb+V+Ti?0.170%, 6.5?(V+Ti)/N?10.5, and 0.30%?CEV?0.48%. The extra thick hot rolled H section steel has a flange thickness of 90 mm-150 mm, has excellent comprehensive mechanical properties, and can well meet the needs for heavy supporting structural parts of high-rise buildings, large squares, bridge structures, etc.

The invention relates to a method of manufacturing steel parts of sheet metal by hot deep drawing characterized by bringing the semi-finished product into austenitic condition by heating, subsequently cooling its locations, which would undergo undesirable deformation, to a temperature below the austenite temperature, and then completing the forming process.

The invention relates to a method of manufacturing steel parts of sheet metal by hot deep drawing characterized by bringing the semi-finished product into austenitic condition by heating, subsequently cooling its locations, which would undergo undesirable deformation, to a temperature below the austenite temperature, and then completing the forming process.

This H section includes, as a chemical composition, C, Si, Mn, Nb, V, Ti, and N; in which the H section includes, as a metallographic structure, ferrite of 60 area % to less than 100 area %, an average grain size of this ferrite is 1 m to 30 m, a thickness of a flange is 20 mm to 140 mm, tensile yield stress is 385 MPa to 530 MPa, and Charpy absorbed energy at 20 C. is 100 J or more.

Rolled H-shaped steel is characterized in that a top 5% average value of Mn concentrations in a most embrittled portion in a flange is 1.6 times or less an Mn concentration at a position of 1/6 in a flange width direction from an end face in the flange width direction and 1/4 in a flange thickness direction from a face of a flange positioned on a side opposite to that of a web, and a top 5% average value of Mn concentrations in a central segregation portion dispersed in a region 15 mm or more apart from a center of the flange width toward one end face or both end faces in the flange width direction and within 2 mm from a flange surface layer in the thickness direction is not less than 1.1 times nor more than 1.6 times the Mn concentration at the position of 1/6 in the flange width direction from the end face in the flange width direction and 1/4 in the flange thickness direction from the face of the flange positioned on the side opposite to that of the web.