VERFAHREN ZUM HERSTELLEN VON SAECKEN AUS THERMOPLATISCHEM KUNSTSTOFF

摘要

A process of manufacturing sacks from synthetic thermoplastic material. A tubular structure is formed from webs of plastic film in that the side portions are infolded and their overlapping margins are adhesively joined by an adhesive seam, tubular sections are severed from the tubular structure and the tubular sections are provided with bottom seam welds and are then filled and provided with top seam welds. The two plastic film webs are moved in unison, and cut sections of oriented plastic material are provided, which cut sections are shorter than the distance between the subsequently formed bottom and top seam welds as measured along the flattened sacks. The cut sections are introduced between the plastic film webs with such a spacing relative to each other that the spaces between the bottom and top seam welds are to be formed. The plastic film webs and the fabric sections are brought together and are laterally offset from each other. The exposed margins of the plastic film webs and of the cut sections are provided with coatings of hot-melt adhesive so that during the subsequent formation of the tubular film the mutually overlapping margins provided with coatings of hot-melt adhesive are adhesively joined. The tubular sections are severed transversely from the tubular film near the centers of the spaces between consecutive cut sections. The transversely extending bottom and top seam welds are formed only between the inner and outer tubular films.