| 摘要 |
The invention relates to a process and an installation for producing packaging bags for liquid or viscous products, the process consisting in making a thermoplastic tubular film (2) by pressing a fused plastic material through a ring nozzle (3), the tubular film (2) so formed being enlarged by means of a gas fed into the tube at a pressure higher than the pressure acting outside the tubular film (2), the plastic material still having a high temperature and being incompletely cured being further flattened using a roller bed (4) and pressed using a pair of pressing rollers (5), so that the inner parts of the resulting bi-layered web (6), pressed to one another, adhere without being joined by fusion, in order to allow the cut thereof along some longitudinal lines using some rotating circular tools (9), thereby resulting some partial webs (7) which are then wound onto some magazine reels (10) which allow the connection between said material and some suction plates (22) acting upon the layers (14 and 15) of the partial web (7) with a view to allowing the insertion of a filler pipe (16) therebetween, said filler pipe (16) containing the product to be packaged, the layers (14 and 15) being further soldered along the free edges using a soldering device (17), the individual packaging units (19) being formed using a sealing device (20), the tubular film (2) being printed afterwards with text or drawings by means of a printing mechanism (8).
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