STEEL MATERIAL CHUCK IN HOT THREE-DIMENSIONAL PROCESSOR, MANUFACTURING METHOD FOR BENT MEMBER AND MANUFACTURING APPARATUS

PROBLEM TO BE SOLVED: To exhibit a sufficient chuck performance by bringing all of a plurality of chuck claws 11 arranged on the inner face of a longitudinal end of a steel material 2 into a sure contact with the inner face of a steel pipe when a bent member is manufactured by a 3DQ device 0.SOLUTION: A chuck of a steel material 2 in a hot three-dimensional device 0 comprises: a plurality of chuck claws 11 arranged inside the longitudinal end of at least one of hollow and long steel materials 2 each having at least one apex and a closed cross section having two sides continuous to both sides of the apex in the cross section circumferential direction; and a chuck claw drive mechanism 12 that drives the plurality of chuck claws 11 in the direction of contact with the inner face of the steel material 2 and in the direction of separation from the inner face. The chuck claw drive mechanism 12 comprises a first chuck claw drive mechanism that drives at least partial chuck claws of the plurality of chuck claws 11 and a second chuck claw drive mechanism that drives other partial chuck claws.SELECTED DRAWING: Figure 4 【課題】３ＤＱ装置0により屈曲部材を製造する際、鋼材2の長手方向の端部内面に配置される複数のチャック爪11を全て鋼管の内面に確実に当接させて十分なチャック性能を発揮する。【解決手段】断面周方向へ少なくとも一つの頂点と頂点の両側にそれぞれ連続する２つの辺とを有し閉じた横断面を有する中空かつ長尺の鋼材2における少なくともの一方の長手方向端部の内部に配置される複数のチャック爪11と、複数のチャック爪11をそれぞれ鋼材2の内面に当接する方向、内面から離反する方向へ駆動するチャック爪駆動機構12とを備える熱間三次元装置0における鋼材2のチャックにおいて、チャック爪駆動機構12は、少なくとも、複数のチャック爪11のうちの一部のチャック爪を駆動する第１のチャック爪駆動機構と、他の一部のチャック爪を駆動する第２のチャック爪駆動機構とを備える。【選択図】図４