The KDDI OCEAN LINK is equipped with ROV MARCAS-IV(ROV:Remotely Operated Vehicle).
MARCAS-IV can dive to a maximum depth of 2,500 meters, and performs cable burial and maintenance.
The burial is performed by taking in a large amount of seawater, waterjetting it into the seabed, and digging a trench.
The maximum burial depth is around 3 meters.
In addition, MARCAS-IV can remove obstacles, or can cut a cable and rope by using its manipulator.
MARCAS-IV will be replaced by the new type of ROV, MARCAS-IV in near future.
(The MARCAS-IV brochure is here.)
Specifications of ROV MARCAS-IV
| Max. Working Depth | 2,500m |
| Dimensions | Length 5.38m (w/2 m jet tool) 6.48m（w/3 m jet tool) Width 3.65m Height 2.96m |
| Weight | 17 tons in air Neutral in sea water |
| Propulsion | Forward/Backward 3 knots Lateral 2 knots Vertical 2 knots |
| Vehicle power | Total 450 kW (225kW Subsea Electric motor x 2) |
| Thruster | 500mm hydraulic driven thruster x 10 |
| Max. Burial Depth | 3.0 m(depending on seabed soil composition) |
| Umbilical Cable | Steel-armored cable 3,500 m |
MARCAS-IV Operating Scene
1. For the cable burial, MARCAS-IV is lifted up by the A-frame of the mother vessel, and is paid out overboard.
2. It is stored in the mother vessel when it is not used, and has an inspection or maintenance for next operation.
3. Control room for ROV MARCAS-IV
MARCAS-IV is on the KDDI OCEAN LINK, and is engaged in submarine cable maintenance.
In the ocean area up to 2,500 meters depth, MARCAS-IV carries out localization of a cable failure point, cutting the cable and its reburial after the repair to maximum depth of 3 meters by Jet Tool Mode.