| 摘要 |
<p>Suction is applied to the components of the sachet for the thermoplastic film, or film-clad material, to be matched from above and below and the edges turned into a seam. When the seam has been welded, suction through apertures in the block is released, while maintained on the mandrel, holding the finished sachet in place while the shaping block is swung clear by cranks. The purpose is to give a clean edge and an even welded seam.</p> |
