Patent attributes
A method and apparatus for making a stepped end on a tube of flexible material includes a tube slitting station having a slitting tool with double edge slitting to provide respective slits beside a first panel and beside a second panel, respectively; a first trimming station trimming a first panel of the tube to a first shortened length, a second trimming station trimming the side gussets to a second length, wherein the second length is longer than the first shortened length; and an adhesive applying station applying adhesive on the tube above and below a fold line across the tube, wherein the tube is adapted to be folded along the fold line, and the adhesive material is adapted to form an adhesive to adhesive seal above and below the fold line.