| 摘要 |
To insulate piping against passage of heat, cold and sound, there are used inter alia preformed insulating sleeves, wrapped glass or rock wool material etc. A continuous sheet-like, flexible covering material in the form of a semi-finished product is used for wrapping round the insulation, said product consisting of a multilayer laminate containing at least two layer groups, the first group forms the outer part of the sheet material when rolled up, and contains a supporting layer consisting of a kraft paper or the like with minor extensibility, and is covered on its outwardly facing surface with a polyethylene layer and similarly on its inner surface with a polyethylene or glue layer while the second group, that forms the inner part of the material when rolled up, contains a layer consisting of a highly extensible paper or the like, which is given a contracting tendency due to its striving to return to its original shape, by being given a high tensional load during manufacture. The highly extensible paper has a polyethylene or glue layer on its surface facing towards the first layer group, said layer being bonded to the corresponding layer in the first layer group or constituting said layer. On its surface, facing the opposite direction, it is protected by a polyethylene layer. Both layer groups are bonded to each other such that the sheet material has an enduring precurvature, characteristic for the sheet material, which thus fits snugly round insulations of different diameters.
|
