Abstract: A jacking system (4) is described for a leg (3) of a jack-up platform (1). The jacking system comprises at least three independent yokes (7a-7d). Each independent yoke is connected to a jack-up structure by at least one vertically arranged double acting actuator (8a-8d?) and is equipped with a leg engaging mechanism such as a horizontally arranged movable locking pin (9a-9d), which is configured to engage or to disengage with a hole of the jack-up leg, in order to transfer a load (L) from the jack-up platform (1) to the leg (3), including a controller configured to operate the yokes (7a-7d) in a way that the leg (3) is moved by all the at least three yokes (7a-7d) in an alternating mode, such that at any moment in time during operation all but one of the at least three yokes (7a-7d) take the load (L) via the associated engaging mechanism, while the remaining yoke of the at least three yokes (7a-7d) makes a return stroke with its engagement mechanism in a disengaged position.

Abstract: A connecting apparatus for two offshore units includes a coupling element with two sets of couplings and resetting facilities that compensate movements between the two offshore units. The coupling element includes a frame connected with the offshore units by two sets of couplings in a manner allowing pivotal movement and rotation. At least one set of couplings includes a first and a second elongated element that are each connected with both the frame and an offshore unit via constructions allowing pivotal movement and rotation. The resetting facilities include a first and a second resilient element that are each stationary connected with the offshore unit and force either the first or the second elongated element to a position extending substantially vertically downwards.

Abstract: A jack-up platform comprising a deck structure, a column with a base structure and a jack-up system for moving the column and the deck structure relative to each other. The base structure comprises a base and at least three base supporting parts, while the deck structure, starting from at least three spaced coupling places, can be connected by a tensioning apparatus with at least three mutually spaced connecting places on or near the base supporting parts. Before the installation the platform, floating with pulled-up column, is brought to the desired location where the base supporting parts are brought into contact with the floor and the deck structure is raised out of contact with the water. After providing the tensioning apparatus and bringing the deck structure to working height, the tensioning apparatus is tensioned, for instance by slightly further raising the deck structure which is then secured relative to the column.

Abstract: A drilling rig, in particular for the offshore industry, in the form of a jack-up platform on which a cantilever is mounted so as to be movable at least substantially horizontally and in a first direction, with the cantilever projecting more or less outside the jack-up platform. On the cantilever a drilling platform is present, which drilling platform is movable relative to the jack-up platform in a second direction, different herefrom. This drilling platform is fixedly mounted on the cantilever while the latter is movable relative to the jack-up platform in both abovesaid directions.

Abstract: A bottom supporting construction for a leg end of a displaceable jack-up platform including a block-shaped leg end part and a supporting element which can be positioned and anchored on a bottom under water and which is provided with a supporting face for a leg end, while a resilient sealing collar, closed upon itself, and a buffer, which in unloaded condition have a height less than that of the sealing collar, are arranged so that when the leg end comes to rest on the supporting element, a space closed off from the environment is formed between that leg end, that sealing collar and the supporting face, and closable discharge is present for enabling water to be discharged from that space. If so desired, upwardly extending support can be arranged on the supporting face, which receive the leg end at least locally with relatively close abutment, so that that support can support the leg end in horizontal direction.