An apparatus and method for feeding sheet film material longitudinally from a roll and for forming and sealing the sheet into tubes comprising roller means for supporting a supply roll of film and for feeding the film, folding means at the edge of the film for folding an edge portion, forming means for forming the film into inner and outer tubes, bullet shaped shaping means for shaping the tubes and overlapping the sheet edges, and anvil and ultrasonic stylus means for engaging and fusing the overlapped sheet edges. The method includes feeding and shaping the sheet into tubes, overlapping the sheet edges, feeding the overlapped sheet edges between an anvil and an ultrasonically energized stylus and energizing the stylus to fuse and seal the sheet edges.