| 摘要 |
<p>Pipe for relining underground pipelines, which is of the composite type having an annularly rigid corrugated outside wall (10) of polymer material, which is connected to the outside surface of a smooth inside wall (11) which consists of a thermoplastic elastomer so that it can be stretched and compressed. According to the invention there is provided on the inside of the smooth inside wall (11) a thin layer (13) of thermoplastic having a lower frictional coefficient and/or greater wear-resistance than the material of the inside wall.</p> |
