To provide a circumferential length correcting method for a metal ring including: a circumferential length measuring step of passing the metal ring around a driving roller and a driven roller, displacing the driving roller and the driven roller away from each other, and measuring the actual circumferential length of the metal ring under tension; and a circumferential length correcting step of correcting the circumferential length of the metal ring by displacing a circumferential length correcting roller by a predetermined displacement in a direction in which the metal ring is extended, and capable of imparting an appropriate arc shape to the metal ring while correcting the circumferential length to fall within an appropriate value range, and a circumferential length correcting apparatus therefor.
Before the circumferential length correcting step, the method includes an arc-shape imparting step of displacing an arc-shape imparting roller 3, which has an arc-shaped outer circumferential surface and is positioned inside the metal ring W, by a predetermined distance in a direction in which the metal ring W is extended, thereby imparting an arc shape W1 conforming to the shape of the outer circumferential surface of the arc-shape imparting roller 3 to the metal ring W.
| JPS59225829 | MANUFACTURE OF SHEET WITH NO SPIKE |
| JPH04344887 | LASER BEAM MACHINING METHOD |
MINEGISHI SEIICHI
YAGASAKI TORU
AOYAMA HIDEAKI
| JP2005282709A | 2005-10-13 | |||
| JPS5850139A | 1983-03-24 |
| WO2002038302A1 | 2002-05-16 |
Takehiro Chiba
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