To obtain a method and an apparatus for bending a long member, with which it is possible to satisfactory bend a long member having wide range variations in tensile yield strength, particularly a long member having low tensile yield strength.
The method for bending the long member has: a step in which the long member is pulled in the longitudinal direction by applying a tensile force which increases from an initial tensile force; a step in which the displacement of the long member after the application of the initial tensile force has started is measured; and a step in which, when the displacement exceeds a tensile rupture threshold value within a predetermined time or when the predetermined time has elapsed without the displacement exceeding the tensile rupture threshold value, bending is performed by simultaneously applying a corrected tensile force smaller than the tensile force at the point of time when the tensile rupture threshold value is exceeded, or the corrected tensile force smaller than the tensile force at the point of time when the predetermined time has elapsed and bending pressure to bend the long member so that the long member assumes a curved line shape in the longitudinal direction.
TAKAGI KAZUYUKI
MATSUBARA AKINORI
MORI YUJI
| JPH11290962A | 1999-10-26 | |||
| JPS53120669A | 1978-10-21 | |||
| JP2000237825A | 2000-09-05 |
Daisuke Ando