Making flat-bottomed bags by forming sheet into tube around filling pipe, welding edges to form longitudinal seam and forming corner welds and cross-welds, one of corner welds forming part of longitudinal seam

摘要

The method involves forming the sheet (1) into a tube around a filling pipe (2), welding the edges to form a longitudinal seam (4) and forming corner welds and cross-welds. The novelty is that one of the corner welds forms part of the longitudinal seam.