摘要 |
<p>A device (1) for making a trench (4) in the bed of an area of water, in particular for laying a pipeline or cable (5) in the bed, comprising a vehicle (1) or the like which can be displaced underwater with respect to the said bed and on which there are at least one or more spray arms (7, 8, 17-26) which, in use, extend substantially vertically downwards next to the pipeline or cable and are provided with spray nozzles (12) for high-pressure water jets, in which device the spray arm comprises first spray nozzles and second spray nozzles which are located at a distance therefrom in the direction of forwards movement of the vehicle.</p> |