| 摘要 |
<p>In order to insert a flexible tubular liner into a conduit without dragging the liner over the interior walls of the conduit whose rough surfaces might damage the liner, the liner is flattened and folded firstly into a plurality of longitudinal strips and then folded secondly into an upper and lower portion with the fold adjacent the mouth of the conduit and the portions extending away therefrom the upper portion being enclosed by two of said longitudinal strips of the lower portion and moving the fold into the conduit and along the liner. The upper portion is now drawn into the conduit by sliding between the two longitudinal strips of the lower portion and is therefore protected thereby from damage caused by direct sliding contact with the interior walls of the conduit. <IMAGE></p> |
