Abstract: A ship for use in offshore operations, with one or more vertical openings (moonpools) in the hull, wherein the deck and/or hull bottom areas between or substantially between and/or otherwise adjacent the openings, are displaced relative to the rest of the deck and/or hull bottom areas of the ship to a position closer to the ship's transverse neutral axis. The area between the rest of the other deck- and hull bottom areas and substantially the displaced area or areas at the openings in the ship and the rest of the deck- and/or hull bottom areas can be stepped in one or more steps, or be shaped as an approximately linear or arcuate junction.

Abstract: When mooring a production ship (10) above a submarine production well, minimum three (usually e.g. eight) anchor lines are used in the form of mooring chains (16b, 16a′, 16b′, 16c′) each extending from a stationary point at the seabed to a separate attachment point on the ship (10). At least one anchor line (16b, 16c) (of a minimum line number of three) has a fixed length and leads to an attachment hook (20) on-board the ship, while the or each of the remaining anchor lines (16a′, 16c′, 16d′), as known per se, has a changeable, shortenable length between the stationary seabed point and a point (34) on the ship (10), e.g. by means of a winch (30) for each of said longitudinally changeable anchor lines (16a′, 16c′, 16d′), simplifying the mooring arrangement constructively and the mooring operations functionally.

Abstract: A swivel device for a ship (10) equipped so as to serve as i.a. a production and/or a drilling ship by exploitation of submarine wells or reservoirs, respectively, containing oil and/or gas, where the ship (10) is formed with a vertically through-going shaft (12). Within the shaft (12), a turret (16) having a substantially vertical axis is rotatably mounted in relation to the hull and is included in said swivel device. Thus, when the turret (16) is moored to the seabed, the ship (10) may turn about said vertical axis, dependent on wind and/or sea currents. The swivel device comprises a first pipe (32) substantially concentrical with the turret (16) and with a smaller external diameter than the internal diameter of the turret (16), so that, between the outside of said first pipe (32) and the inner side of the turret (16), a vertically through-going annulus is formed for accommodating of several production risers (34).

Abstract: To permit use of a ship as production ship, among other things in conjunction with a so-called STL-buoy (30) and in test production without a buoy (30), and in which the ship (10) is formed with a bottom recess (12) for the reception of the buoy (30) in a mutually pivotal manner, there has been formed, immediately above said bottom recess (12), a vertically oriented cavity (14) in the ship's hull. In this cavity (14) is pivotally supported a sleeve-shaped turret (16) which is configured with at least one through bore, channel or other passage for passing pipelines (24, 24′), pipeline portions (38, 38′), or the like, which may be connected at the one end via a swivel device (22) to one or more pipes or the like (26) fixed in the vessel. The sleeve-shaped turret (16) works alone during test production, but is connected to the buoy (30) so that together they form a turret (16, 30) in regular production.