Abstract:
A method of making an island 28, 47 including the steps of: manufacturing a plurality of formations 10, 31 , 32; transporting the formations 10, 31, 32 to a site in a water body 18, 37; assembiing said formations 10, 31, 32 proximate one another; said formations 10, 31, 32 defining an artificial island structure with both below and above water line components 10, 31, 32. Methods are described, as well as methods and components for both island and existing island and land enhancements.
Abstract:
A support (4) for an elevated mass (6, 8) , comprising at least three extended, mutually trussless supporting columns (14, 14', 14", 14"') , and where the longitudinal axes of the supporting columns (14, 14', 14", 14"') meet near the centre of gravity (20) of the elevated mass (6, 8) .
Abstract:
Es wird eine Unterbaukontruktion (4) für eine Bohranlage mit einer einen Bohrmast (1) tragenden Bohrplattform (3) vorgeschlagen, wobei die Unterbaukonstruktion (4) aus einer Mehrzahl von Modulen (41) aufgebaut ist, deren Außenmaße und Aufhängungspunkte mit denen eines Standardseecontainers übereinstimmen.
Abstract:
An offshore base (10), particularly but not exclusively for a offshore wind turbine, is described. The base has two or more legs (14) radiating from a central support structure (12), wherein the legs are wholly or substantially formed from plate steel. The invention provides a simpler form of construction for an offshore base, replacing the currently used tubular steel pieces, which have difficult welding arrangements and subsequent weak stresses, with a far simpler straight welding arrangement, with stronger stress points, and/or more easily reducible stress points by the use of stiffeners in a manner well known to those skilled in the art. One embodiment of the current invention has been shown to provide a suitable base for an offshore wind turbine using an 8m significant wave height, water depth up to 15m and current speed of around 2m. The embodiment uses common jack-up, lifting and piling equipment, keeping pile diameters and length generally less than lm and 25m respectively.
Abstract:
The invention relates to a watercraft for providing maintenance to a wind energy facility, which is characterized by a stabilization device consisting of a plurality of support columns (36) placed in the hull (32) of the craft in such a way that they can be lowered, lift tanks (34) provided in the support columns (36) and a device for pumping out or flooding the lift tanks (34).
Abstract:
The invention relates to a leg assembly for an offshore structure, such as a self-elevating jack-up rig. The leg assembly has a pair of parallel leg chords (40, 42) divided into a plurality of sections by transverse bracing members (46). A unit of angular bracing members (50, 58, 62, 66) is secured within each such section. The unit has four angular members defining a rhombus, with each angular bracing member attached to a transverse bracing member and an adjacent leg chord.
Abstract:
The invention relates to a method for installation of windmills at sea. The windmills are placed upon beds on the sea bottom, with bed and windmill comprising tower, mill top and rotor assembled in mainly one piece in another location than the final location of the windmill. The invention is characterized in that the bed and the windmill in one piece is shipped by means of a craft and brought to the place for the final location, and that bed and windmill in one piece under application of a crane such as a floating crane is placed on the final location. The invention relates as well to a bed for windmills. The bed comprises a base piece and one on the base piece placed plinth part, upon which the windmill tower may be placed and fastened, so that the base piece of the bed is composed of essentially uniformly formed base piece segments, which together make up the base piece of the bed. Furthermore, the invention relates to an application of such a bed.
Abstract:
A floatable structure (10, 12) such as a jack-up barge has a plurality of legs (14) upon which the structure may be supported and raised. Each leg is pivotable between an upright operative position and a recumbent storage position and means such as hydraulic rams (22) are provided for producing pivoting of said legs between said positions. Each leg may be carried by a jacking collar (16) with respect to which the leg is jackable to extend the leg when in the operative position, each jacking collar being pivotable by said rams to carry the respective leg between said operative and storage positions.
Abstract:
A method and apparatus for erecting and removing offshore structures including a jacket (100) and a platform (7a) is disclosed. The system of the invention includes a platform-lifting unit (2), a jacket lifting unit (110), and a control unit (1). The platform-lifting unit (2) includes a laterally and vertically movable truss member (4a), which is hingedly connected to a barge (2a) with lifting beams (5a), and a means for positioning the truss member at desired height and at lateral displacement above the barge (2a). The jacket-lifting unit (110) contains a ballast tank structure (113) connected to a strong back (16a) that has a plurality of grappling members (19). The control unit (1) contains all supporting and controlling systems for the other units. To remove the platform (7a), the truss member (4a) of the platform lifting unit (2) is moved underneath the platform, the truss is raised to exert force on the platform, the platform is severed from the jacket (100) and the platform is moved on top of the barge (2a). To remove the jacket (100), the jacket-lifting unit (110) is lowered by controllably flooding the ballast sections (3) at varying rates, the grappling members (19) are securely attached to the jacket structure (100), the jacket-lifting unit is pulled by the control unit (1), to tilt the jacket, and the ballast sections are deballasted to controllably lift and float the jacket.
Abstract:
A method serves to mount the piles (6) associated with the installation of a pile-founded offshore platform, e.g. a production platform, wherein these are driven down into the sea bed through pile guides (12) attached to or forming part of the foundation (16) of the platform. A device for performing the method comprises at least one chute (15) which is preferably C- or U-shaped in cross section and which extends with a suitable inclination upwardly from the upper end (13) of a pile guide (12) to at any rate substantially in below the position which the pile tip (8) of a pile (6) to be placed in the pile guide (12) assumes in said freely hanging position of the pile (6). A conventional drilling rig may be used for installation of in particular smaller platforms, thus providing great savings in terms of economy and frequently also in terms of time.