| 摘要 |
PURPOSE:To produce deformed section bars having no twists by rolling blank materials with grooved rolls so as to roll down the parts to be thin-walled but not to roll down the parts to be thick-walled. CONSTITUTION:A bar 1 having a flat plate-like section molding which is a blank material is moved longitudinally between a grooved rolls 3 having a groove 2 provided on at least one surface side thereof and a roll 4 provided on the opposite side. While the thin-walled part 5 to be thin-walled in the transverse direction of the bar 1 is rolled down between a projecting surface part 6 of the roll 3 which delineates the part 2 and the roll 4, the bar receives no rolling down effect in the thick-walled part 7 to be thick-walled in the transverse direction located in the position corresponding to the groove 2. Thus, the flow by the deformation of the part 5 moves to the part 7 which is not applied with the rolling down force, that is, into the part 2, thereby packing the part 2. The generation of the difference in the longitudinal or rolling direction occuring in the difference in the wall thickness in the transverse direction is thus prevented, and the generation of twists after the rolling is eliminated. |
