| 摘要 |
<p>In the packaging field certain types of packages are manufactured from pre-shaped, cylindrical casings made from a heat-shrinkable laminate. The casings are formed by winding a material sheet around a mandrel and subsequent sealing together of the overlapping ends of the sheet. However, because of the stiffness of the material the leading end of the sheet protrudes tangentially from the mandrel during the winding and prevents an accurate adaptation of the material sheet to the surface of the mandrel. According to the method and arrangement of this invention this disadvantage is avoided in that the leading end of the sheet is pre-heated on the side facing the mandrel to such a degree, that the shrinking is initialled. The shrinking of one side only results in that the leading end of the material sheet is given a curved shape with a radius that coincides with the radius of the mandrel, and consequently the leading end is no longer an obstacle to the winding.</p> |
