To provide a method for straightening a U-shaped steel sheet pile, capable of properly straightening warpage of both the left and right joint parts 104 of a U-shaped steel sheet pile having arm parts formed between each joint part and flange part, and an apparatus therefor.
Straightening is conducted by a roller straightening apparatus 10 having a plurality of straightening rolls arranged above and below in a zigzag pattern. At least one of the plurality of straightening rolls is used as a rolling-reduction roll capable of concentrically applying rolling-reduction to the arm parts 103 and/or the joint parts 104 of the U-shaped steel sheet pile and further adjusting the amounts of the rolling-reductions at the left and right sides. Each of the amounts of the rolling-reductions that are applied to the left and right arm parts 103 and/or the left and right joint parts 104 by the rolling-reduction roll is adjusted according to the difference between the amounts of warpage of the left and right joint parts 104 of the U-shaped steel sheet pile 100.
YOSHIDA YOSHIKAZU
AZUMA ETSUO
HOASHI YUKIHIRO
Kazuhiro Mori