Review of Cabling Techniques and Environmental Effects Applicable
Review of Cabling Techniques and Environmental Effects Applicable
Review of Cabling Techniques and Environmental Effects Applicable
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<strong>Review</strong> <strong>of</strong> <strong>Cabling</strong> <strong>Techniques</strong> <strong>and</strong> <strong>Environmental</strong> <strong>Effects</strong> <strong>Applicable</strong> to the Offshore Wind<br />
Farm Industry – Technical Report<br />
cutter consists <strong>of</strong> a rotating wheel disc <strong>and</strong> is fitted with a number <strong>of</strong> replaceable<br />
rock cutting teeth. Progress is slow (100m/hr to 500m/hr) using these vehicles<br />
<strong>and</strong>, in extreme cases, progress <strong>of</strong> only tens <strong>of</strong> metres can be made in a full day<br />
<strong>of</strong> trenching operations. It is <strong>of</strong>ten the case that the vehicle has to be recovered<br />
for the cutting teeth to be replaced as they abrade quickly in the rock material<br />
thus losing their effectiveness in cutting mode. Owing to the very aggressive<br />
nature <strong>of</strong> the cutting tool, the cable is carefully guided through the tracked cable<br />
burial vehicle through an enclosed cable pathway over the top <strong>of</strong> the rock wheel<br />
cutter before being guided to the base <strong>of</strong> the cut trench. Diver intervention is<br />
usually required in any cable loading <strong>and</strong> unloading process. Figure 3.18 shows<br />
a shallow water tracked cable burial machine which is fitted with a rock wheel<br />
cutter, but has the flexibility to interchange to a mechanical chain excavator if<br />
required.<br />
Figure 3.18: Shallow Water Tracked Cable Burial Machine Fitted with<br />
a Rock Wheel Cutter<br />
(Photo courtesy <strong>of</strong> The Engineering Business Ltd)<br />
Mechanical chain excavators<br />
Mechanical chain excavators are typically used in circumstances where the<br />
seabed material is beyond the capability <strong>of</strong> a jetting system or where deeper<br />
burial is required. Mechanical chain excavators typically operate in the 2.5m<br />
to 3.0m trench depth range as opposed to the 1.0m to 1.5m depth range that<br />
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