Abstract: A drilling unit on a deck of a floating vessel, includes a drill tower structure with a heave-compensation system, a winch mounted at or near the deck, a crown block mounted at a top side of the drill tower structure and at least one wire rope between the winch and the crown block. The heave-compensation system includes a slideable support frame configured to be moved in a direction substantially parallel to the axial direction of the drill tower structure. Either the winch or the crown block is positioned within the slideable support frame such that a distance between the winch and the crown block is controlled by at least one electric motor or linear actuator. In an alternative embodiment in which a crown block in not employed, the winch is placed in the slideable support frame at the top side of the drill tower structure.

Abstract: A tow line controlling device and a method of operation of a tow line controlling device in which the tow line controlling device is positioned in a deck of a vessel. The tow line controlling device includes at least two vertical tow pins that are movable between a passive position and at least one active position, and includes a gap between two of the tow pins, and the gap is spanned by a bridge formed by the two tow pins at least when the tow pins are in one of their active positions. The tow line controlling device also includes a lower stopper that is movable between a passive position and at least one active position and is positioned between two of the tow pins.

Abstract: There is described a system for hoisting a load on an offshore rig, the system comprising a winch having a winch drum; drive means for operating said winch; one or more sheaves; an elongated hoisting member, such as a wire rope, configured to run over said one or more sheaves and to connect said winch to a load, wherein said winch drum, in a first position of use (A), is configured to accommodate only a single layer of said elongated hoisting member.

Abstract: A tow line controlling device and a method of operation of a tow line controlling device in which the tow line controlling device is positioned in a deck of a vessel. The tow line controlling device includes at least two vertical tow pins that are movable between a passive position and at least one active position, and includes a gap between two of the tow pins, and the gap is spanned by a bridge formed by the two tow pins at least when the tow pins are in one of their active positions. The tow line controlling device also includes a lower stopper that is movable between a passive position and at least one active position and is positioned between two of the tow pins.