| 摘要 |
Conventionally designed district heating pipes assembled from prefabricated heat insulated pipe elements (2, 4) are not well suited for being mounted in the underground by the so-called horizontal drilling technique, because the associated exterior sealing sleeves (16) arranged over the pipe element joints may be axially displaced if they meet with obstructions during their insertion through the subsoil bore. According to the invention, the conventional joints may still be used, if only the said sleeves, with reduced diameter, are mounted between narrowed ends (12) of the exterior mantle pipes (10) of the pipe elements (2, 4). <IMAGE> |
