Method of mooring of ship and arrangement to accomplish the method

Abstract

Methods and arrangements of releasably mooring a ship in a definite position at a distance from land with an ability to return later to the same place. The mooring is accomplished by means of a substantially ring-shaped mooring unit, which can be raised and lowered and which has a gap along its periphery, which can be connected to and disconnected from the ship by a connectable part located below the surface of the water. The mooring unit enables a ship carrying a downwardly protruding load to pass by after disconnection and lowering of the mooring unit, and to be rotated round an essentially vertical imaginary axis.

Description

technical field [0001] The present invention relates to a method of enabling the mooring of a vessel at a defined location at a distance from land and possibly leaving the vessel from its associated berth / moorage. Background technique [0002] For floating vessels, dynamic positioning (DP) and / or mooring systems are used in order to prevent the vessel from moving, ie to keep it in a defined position. Depending on the assigned task of the vessel and the relevant water depth, various requirements are placed on the immobility of the vessel or, conversely, on the maximum permissible deviation from a determined position. [0003] The ability of the vessel to maintain an established position depends on the reaction time of the DP system to resist / offset environmental forces due to wind, waves and swells. In certain waters, ships may also be affected by forces caused by ice floes. A DP system comprises: a thruster, ie a thruster, which can rotate 360 ​​degrees in the horizontal p...

AI Technical Summary

Problems solved by technology

[0006] Another complication is that during certain operations a steel pipe, the so-called "riser", is used between the valve at the seabed and the vessel

Pulling / retracting the "riser" before the riser disconnects is too time-consuming, so the arrangement must be designed so that disconnection can be achieved without pulling / retracting the "riser" to vessel

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