| 摘要 |
<p>The pipe (1) has a base pipe (2), and an in-extruded strip-shaped layer (3a) arranged at an inner surface, where another in-extruded strip-shaped layer is arranged at an outer surface of the base pipe. The layers are arranged in a spaced manner such that the density of a material of the strip-shaped layers is different from the density of the base pipe material. The strip-shaped layers at the inner and/or outer surfaces have same strip width and are regularly arranged over the circumference of the plastic tube.</p> |
