| 摘要 |
<p>A vehicle (40) for laying a pipe (42) in a trench (44) in the sea floor (46) is disclosed. The vehicle has two operational modes, a first mode for cutting a trench in a sea floor with a soft upper layer and a hard lower layer and a second mode for a sea floor of hard material throughout the depth of the trench. The vehicle has three cutting chains (56,58,60), the forward most chain, that is only used when the second mode cuts a shallow central section of the trench from a first side. A centrally positioned cutting chain (56), that is used in both modes, cuts the next portion of the trench to its full depth from the opposite side that the forward most cutting chain (58) operates. A rear most cutting chain (60) cuts the final portion of the trench to its full depth, therefore partially overlapping with the previous portion, and operates from the same side of the trench (44) as the forward most cutting chain (58).</p> |
