Tension Control
Cranemaster will decouple the motion of the boom-tip from a load which is fastened to the sea bed or to a subsea structure. It is therefore possible to use Cranemaster to keep a load in position without releasing the tension in the crane/winch wire.
Operational Challenges
Rapid heeling of vessel during installation of heavy objects.
Instability between touch-down and fastening.
Suction forces combined with vessel movements creating large dynamic forces in crane and wire.
Keeping tension during sawing and cutting.
Cranemaster Benefits
Constant tension despite vessel movements.
Fail safe constant tension functionality.
Works as a constant tension system, but with added dampening preventing abrupt movements.
Overload protection.
Typical examples of use
- Removal of objects from the sea floor.
- Installation of heavy objects to reduce rapid heeling of the vessel.
- Avoid instability of object between touch-down and fastening.
- Keep tension during operation (sawing, cutting, etc.).
Adjustment and fine tuning of position after touch-down
There are many reasons why the position of a manifoild, transition piece or other object has to be adjusted after initial touch-down. Cranemaster is ideally suited to keep a certain tension in the wire after touch-down, either to ease the moving of the object without lifting it, or to avoid instability of the object. For both situation Cranemaster will also decouple the wave motion from the load.
Compensation for tool-weight subsea
For subsea tasks such as cutting/sawing during decomissioning, it might be preferable to compensate for the weight of the tool in water. By having Cranemaster tuned to the correct weight, this can be easily acheived.
Featured References – Tension Control
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Cranemaster used for load test on Normand Seven
Customer Challenge: The vessel Normand Seven was chartered from Solstad Offshore ASA by Subsea 7 and converted into a subsea pipe laying vessel for a long-term contract in Brazilian waters. Subsea 7 [...]