| 摘要 |
In each cycle of a sequence of repetitive cycles a longitudinal section of an elongated, continuous piece of material spaced from the free end of the piece is draped about an arcuate face of a mandrel by a bending tool moving about the axis of curvature of the mandrel face, and the free end of the piece is thereby engaged with the arcuate face of another mandrel and secured to the other mandrel, whereupon the section draped over the first mandrel is cut. The central portion of the blank severed thereby from the continuous piece is draped over the second mandrel bent into a ring, the curvature of the leading and trailing blank portion, being due to previous draping over the first mandrel.
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