Page 235 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition
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224 CHAPTER 9 LARS and TMS
Drag
Clump weight
FIGURE 9.3
Clump weight deployed ROV.
Drag
FIGURE 9.4
Cage deployed ROV.
Cage
depth for a distance of 500 ft (150 m) or more from the point of the clump weight, cage, or top hat. As discussed above, most operators refer to the TMS as the entire system of cage or “top hat” deployment, tether management, vehicle protection, and junction point for the surfacevehicle link. Technically, the TMS is the tether-handling machinery only.
Clump deployed
The use of a clump weight has become prevalent in the observation-class category. If working on or near the sea bottom, clump weights enable the ROV operator to easily manage the tether “lay” from the insertion point next to the vessel all the way to the clump weight location either mid-water or next to the bottom.
This allows the weight to absorb the cross-section drag of the current, relieving the submersible of the tether drag from the surface to the working depth. The vessel can be maneuvered to a point
Umbilical Umbilical
Tether
Tether
