Production method and production facility for steel sheet pile with flanges

Abstract

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.

1 . A production method for forming a steel sheet pile with flanges from a material to be rolled by caliber roll rolling, the production method comprising a step of performing reverse rolling on the material to be rolled by a same caliber, wherein:
 the step of performing reverse rolling comprises 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 comprises 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.   
     
     
         2 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein:
 the step of performing reverse rolling comprises a step of forming a web corresponding part and arm corresponding parts;   the caliber comprises a web facing portion for forming the web corresponding part and arm facing portions for forming the arm corresponding parts;   the caliber comprises web-side flange facing portion groups each including at least one of the second flange facing portions and arm-side flange facing portion groups each including at least one of the third flange facing portions; and   with respect to a straight line linking a boundary part between the web-side flange facing portion group and the web facing portion and a boundary part between the arm-side flange facing portion group and the arm facing portion, the second flange facing portion is in a protruding shape in a flange outside direction, and the third flange facing portion is in a protruding shape in a flange inside direction.   
     
     
         3 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein rolling in which a flange elongation λf 1  at the first flange part is smaller than flange elongations λf 2 , λf 3  at the second flange part and the third flange part is performed in the caliber. 
     
     
         4 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein the step of forming the first flange parts, the second flange parts, and the third flange parts is an intermediate rolling step. 
     
     
         5 . The production method for a steel sheet pile with flanges according to  claim 4 , wherein the caliber has a caliber shape opened at both end parts in a width direction. 
     
     
         6 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein the flange corresponding parts in a bent shape formed in the material to be rolled by the step of forming the first flange parts, the second flange parts, and the third flange parts are rolled and shaped into a desired flat shape by rolling in a caliber at a stage subsequent to the step of forming the first flange parts, the second flange parts, and the third flange parts. 
     
     
         7 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein rolling is performed in the caliber so that the flange elongation λf 1  at the first flange part becomes a web elongation λw or less. 
     
     
         8 . The production method for a steel sheet pile with flanges according to  claim 1 , wherein the steel sheet pile is a hat-shaped steel sheet pile. 
     
     
         9 . A production facility for forming a steel sheet pile with flanges from a material to be rolled by caliber roll rolling, the production facility comprising a rolling mill which performs reverse rolling on the material to be rolled by a same caliber, wherein:
 the rolling mill which performs reverse rolling comprises a caliber which forms first flange parts across a neutral line and second and third flange parts arranged on both sides of the first flange parts;   the caliber comprises 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.   
     
     
         10 . The production facility for a steel sheet pile with flanges according to  claim 9 , wherein:
 the rolling mill which performs reverse rolling comprises a caliber which forms a web corresponding part and arm corresponding parts;   the caliber comprises a web facing portion for forming the web corresponding part and arm facing portions for forming the arm corresponding parts;   the caliber comprises web-side flange facing portion groups each including at least one of the second flange facing portions and arm-side flange facing portion groups each including at least one of the third flange facing portions; and   with respect to a straight line linking a boundary part between the web-side flange facing portion group and the web facing portion and a boundary part between the arm-side flange facing portion group and the arm facing portion, the second flange facing portion is in a protruding shape in a flange outside direction, and the third flange facing portion is in a protruding shape in a flange inside direction.   
     
     
         11 . The production facility for a steel sheet pile with flanges according to  claim 9 , wherein a flange elongation λf 1  at the first flange part is smaller than flange elongations λf 2 , λf 3  at the second flange part and the third flange part in the caliber. 
     
     
         12 . The production facility for a steel sheet pile with flanges according to  claim 9 , wherein the caliber is a caliber provided in an intermediate rolling mill. 
     
     
         13 . The production facility for a steel sheet pile with flanges according to  claim 12 , wherein the caliber has a caliber shape opened at both end parts in a width direction. 
     
     
         14 . The production facility for a steel sheet pile with flanges according to  claim 9 , further comprising a subsequent-stage caliber which rolls and shapes the flange corresponding parts in a bent shape formed in the material to be rolled by rolling in the caliber which forms the first flange parts, the second flange parts, and the third flange parts, into a desired flat shape. 
     
     
         15 . The production facility for a steel sheet pile with flanges according to  claim 9 , wherein the flange elongation λf 1  at the first flange part is a web elongation λw or less in the caliber. 
     
     
         16 . The production facility for a steel sheet pile with flanges according to  claim 9 , wherein the steel sheet pile is a hat-shaped steel sheet pile.