| 摘要 |
<p>In the bending in a bending plane of a multiple tube (6) having a plurality of compartments (7,8) extending side-by-side in the longitudinal direction of the tube, a bending location is moved progressively along the tube and during bending a mandrel (12,13) is located inside each said compartment at the bending location. To improve control of the tube shape, during at least part of the bending the position of at least one of the mandrels (12,13) relative to the tube at the bending location varies in dependence on at least one parameter of the bending. At least one of said mandrels (12,13) may be free to move, under constraint by a resilient force, in the longitudinal direction of the tube.</p> |
