A facility cost and a remodeling cost can be reduced, and further, a steel sheet pile product with high dimensional accuracy is produced by suppressing occurrence of warpage of a material to be rolled during bending. There is provided a bending device which produces a steel sheet pile by performing bending on a material to be rolled after being subjected to rough rolling, intermediate rolling, and finish rolling in a hot state, in a direction of increasing a cross sectional height of the material to be rolled, the bending device including: a forming stand including a forming caliber configured by an upper caliber roll and a lower caliber roll; and a drive unit driving either the upper caliber roll or the lower caliber roll.

A facility cost and a remodeling cost can be reduced, and further, a steel sheet pile product with high dimensional accuracy is produced by suppressing occurrence of warpage of a material to be rolled during bending. There is provided a bending device which produces a steel sheet pile by performing bending on a material to be rolled after being subjected to rough rolling, intermediate rolling, and finish rolling in a hot state, in a direction of increasing a cross sectional height of the material to be rolled, the bending device including: a forming stand including a forming caliber configured by an upper caliber roll and a lower caliber roll; and a drive unit driving either the upper caliber roll or the lower caliber roll.

There is provided a production method for a hat-shaped steel sheet pile including performing rough rolling, intermediate rolling, and finish rolling on a material to be rolled through hot rolling, and then performing bending forming, in which the material to be rolled is composed of a web corresponding part, flange corresponding parts, arm corresponding parts, and joint corresponding parts, corner parts as worked parts are formed at connection places between the web corresponding part and the flange corresponding parts and connection places between the flange corresponding parts and the arm corresponding parts, the intermediate rolling is carried out by performing rolling in a plurality of passes on the material to be rolled in a hot state by using a caliber provided to upper and lower caliber rolls in one or a plurality of intermediate rolling mills in which one stand is configured by one caliber, at a height lower than a predetermined target product height, the bending forming is performed in a hot state and performed in a state where the worked parts have a temperature of transformation point or higher, and in the bending forming, the material to be rolled is formed to have predetermined target height and target width.

There is provided a production method for a hat-shaped steel sheet pile including performing rough rolling, intermediate rolling, and finish rolling on a material to be rolled through hot rolling, and then performing bending forming, in which the material to be rolled is composed of a web corresponding part, flange corresponding parts, arm corresponding parts, and joint corresponding parts, corner parts as worked parts are formed at connection places between the web corresponding part and the flange corresponding parts and connection places between the flange corresponding parts and the arm corresponding parts, the intermediate rolling is carried out by performing rolling in a plurality of passes on the material to be rolled in a hot state by using a caliber provided to upper and lower caliber rolls in one or a plurality of intermediate rolling mills in which one stand is configured by one caliber, at a height lower than a predetermined target product height, the bending forming is performed in a hot state and performed in a state where the worked parts have a temperature of transformation point or higher, and in the bending forming, the material to be rolled is formed to have predetermined target height and target width.

To suppress a material amount deficiency in arm parts which occurs at a rough shaping stage to produce a hat-shaped steel sheet pile product in a good shape when a large-size hat-shaped steel sheet pile is produced using a raw material in a rectangular cross-sectional shape (slab). A production method for producing a hat-shaped steel sheet pile by reducing a rectangular cross-sectional raw material, includes: edging rolling of performing reduction in a width direction on the rectangular cross-sectional raw material; and a first forming rolling of performing reduction in which a cross section of a material to be rolled after the edging rolling is formed into a substantially hat-shaped cross-sectional shape, wherein in the edging rolling, reduction in which a thickness of end parts in the width direction of the material to be rolled is increased using an edging caliber being a restraining caliber having a caliber bottom width T3 larger than a thickness T1 of the rectangular cross-sectional raw material to form into a dog-bone shape is performed.

To suppress a material amount deficiency in arm parts which occurs at a rough shaping stage to produce a hat-shaped steel sheet pile product in a good shape when a large-size hat-shaped steel sheet pile is produced using a raw material in a rectangular cross-sectional shape (slab). A production method for producing a hat-shaped steel sheet pile by reducing a rectangular cross-sectional raw material, includes: edging rolling of performing reduction in a width direction on the rectangular cross-sectional raw material; and a first forming rolling of performing reduction in which a cross section of a material to be rolled after the edging rolling is formed into a substantially hat-shaped cross-sectional shape, wherein in the edging rolling, reduction in which a thickness of end parts in the width direction of the material to be rolled is increased using an edging caliber being a restraining caliber having a caliber bottom width T3 larger than a thickness T1 of the rectangular cross-sectional raw material to form into a dog-bone shape is performed.

To suppress the occurrence of a defective shape such as a flange wave or the like by reverse rolling so as to improve the product dimension accuracy and stability of rolling. A production method for forming a steel sheet pile with flanges from a material to be rolled by caliber roll rolling, includes a step of performing reverse rolling on the material to be rolled by a same caliber, wherein: the step of performing reverse rolling includes a step of forming first flange parts across a neutral line and second and third flange parts arranged on both sides of the first flange parts; the caliber includes first flange facing portions for forming the first flange parts, second flange facing portions for forming the second flange parts, and third flange facing portions for forming the third flange parts; and an inclination angle of the first flange facing portion with respect to a horizontal plane is larger than inclination angles of the second and third flange facing portions.

To suppress the occurrence of a defective shape such as a flange wave or the like by reverse rolling so as to improve the product dimension accuracy and stability of rolling. A production method for forming a steel sheet pile with flanges from a material to be rolled by caliber roll rolling, includes a step of performing reverse rolling on the material to be rolled by a same caliber, wherein: the step of performing reverse rolling includes a step of forming first flange parts across a neutral line and second and third flange parts arranged on both sides of the first flange parts; the caliber includes first flange facing portions for forming the first flange parts, second flange facing portions for forming the second flange parts, and third flange facing portions for forming the third flange parts; and an inclination angle of the first flange facing portion with respect to a horizontal plane is larger than inclination angles of the second and third flange facing portions.

To suppress the shape defect at a bite end part of a material to be rolled at a bending rolling stage of a rough rolling step to achieve improvements in productivity such as an improvement in yields and a decrease in crop in production of a steel sheet pile. A production method for producing a steel sheet pile by reducing a raw material in a rectangular cross-section, includes a rough rolling step, an intermediate rolling step, and a finish rolling step, wherein a rolling mill configured to perform the rough rolling step is provided with a caliber configured to perform bending rolling of extending a thickness center line length of the raw material and rolling and shaping the raw material from a rectangular cross-sectional shape to a substantially steel sheet pile cross-sectional shape, and wherein in the bending rolling, rolling that a reduction amount with respect to a predetermined section of a bite end part of the raw material is smaller than a reduction amount with respect to a part other than the predetermined section is performed.

To suppress the shape defect at a bite end part of a material to be rolled at a bending rolling stage of a rough rolling step to achieve improvements in productivity such as an improvement in yields and a decrease in crop in production of a steel sheet pile. A production method for producing a steel sheet pile by reducing a raw material in a rectangular cross-section, includes a rough rolling step, an intermediate rolling step, and a finish rolling step, wherein a rolling mill configured to perform the rough rolling step is provided with a caliber configured to perform bending rolling of extending a thickness center line length of the raw material and rolling and shaping the raw material from a rectangular cross-sectional shape to a substantially steel sheet pile cross-sectional shape, and wherein in the bending rolling, rolling that a reduction amount with respect to a predetermined section of a bite end part of the raw material is smaller than a reduction amount with respect to a part other than the predetermined section is performed.