Remodelling hollow bodies with respect to the shape of the cross-section (remodelling end portions only B21K21/12)

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Making hollow articles not covered by a single preceding sub-group (essentially from sheet-metal or uniform thin-walled tubes B21D, e.g. B21D41/00, B21D51/00) > Remodelling hollow bodies with respect to the shape of the cross-section (remodelling end portions only B21K21/12)