Method of establishing and/or operating a bore well in a seabed and a drilling vessel for use in connection therewith

A drilling vessel comprising

• a drilling barge having a part carrying a derrick and associated drilling equipment;
• a larger supporting floatable vessel having an upper deck that is configured to receive the drilling barge in a position in which the drilling barge part carrying the derrick extends beyond the deck of the supporting vessel, means being provided for interconnecting the drilling barge and the supporting vessel in said position;
• means for anchoring the barge in relation to a seabed by submerging the supporting vessel so as to position said vessel in contact with the seabed;
• and
• supporting spacing means arranged between the drilling barge and the supporting vessel, so as to position the drilling barge and the drilling equipment thereon in a desired position in relation to the seabed.

A method of establishing and/or operating a bore well in a bed or floor under a body of water at a selected location of operation by means of a drilling barge or vessel having a derrick or rig and associated drilling equipment, said method comprising the steps of:

• providing a plurality of separate, floatable sub-vessels at a first location remote to the selected location of operation, the size and dimensions of each sub-vessel allowing for transportation of the sub-vessels on rivers or other narrow waterways;
• towing the sub-vessels from the remote first location via such narrow waterway to a second location adjacent to or closer to the selected location of operation;
• interconnecting the sub-vessels at said second location so as to form a barge;
• mounting the derrick or rig and associated drilling equipment on the barge thus formed;
• moving the drilling barge to the selected location of operation;
• and
• anchoring the drilling barge in relation to the bed or floor under said body of water so as to substantially align the derrick with the existing or planned bore well.

A set of separately floatable sub-vessels for forming a drilling barge or vessel, said set comprising:

• a plurality of elongated first sub-vessels adapted to be arranged in side-by-side relationship so as to extend in the longitudinal direction of the vessel, the size and dimensions of each sub-vessel allowing for transportation of the sub-vessels on rivers or other narrow waterways, said sub-vessels having tanks formed therein, and each sub-vessel having connecting means for interconnecting the sub-vessels in a floating condition and comprising drawing equipment for drawing the sub-vessels into mutual adjacent positions;
• mechanical interlocking means for temporarily interconnecting the sub-vessels in such position, and means for subsequently interconnecting the sub-vessels more permanently, each sub-vessel defining a deck part and a bottom part forming in the interconnected condition of the sub-vessels the deck and the bottom, respectively, of the vessel;
• and
• a drilling rig or derrick to be mounted on the deck of the vessel.