| 摘要 |
To make plastic carrying bags or sacks, sections are cut or are severed by hot wire welding from a gusseted tubular film by a formation of transverse seam welds and transverse severing cuts or by hot wire-welded transverse seam welds. At least in their bottom portion the sections are provided with corner seam welds, which are separately formed in the two folds and which diverge obliquely from the outer fold lines toward the top and/or bottom seam weld and terminate short of the inner fold line and merge into the latter. To prevent in the making of the carrying bags an elongation of the intermediate portion of the tubular film, the latter is initially formed with corner seam welds only in one fold of each of the two gussets before the transverse seam welds and transverse severing cuts or hot wire-welded transverse seam welds are formed. When said corner seam welds have cooled, congruent corner seam welds are formed in the respective other folds.
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