Abstract:
A floating offshore platform is disclosed with one or more extension plates fixedly coupled to one or more pontoons on the offshore platform and extending from the pontoons. As the floating platform moves, the pontoon-coupled extension plates separate the water and cause drag on the platform. The water moving with the extension plates also increases the dynamic mass. The added drag and dynamic mass increases the natural period of the motion away from the wave excitation period to minimize the wave driven motion compared to a platform without the extension plates. The extension plates can be coupled to the pontoons during fabrication at the yard directly or through frame members. The extension plates generally are generally located inclusively between the top and bottom elevations of the pontoons, and therefore do not significantly reduce the clearance between the seabed and the hull at the quayside.
Abstract:
The present disclosure provides in at least one embodiment a rotatable keel skirt assembly on a rectangular-shaped keel pontoon. The rectangular-shaped keel pontoon reduces the maximum hull width by a significant percentage compared to a circular-shaped keel pontoon while maintaining the same hull motion performance. The rotatable keel skirt assembly allows the size of the pontoon to define the width of the hull during some fabrication phases of the platform, rather than the additional width of the keel skirt assembly. Thus, the outreach of the crane and other equipment can be effectively used as if the keel skirt assembly was not present. After fabrication, the hull can be moved away from the quayside and the keel skirt assembly can be rotated into position for service. Various systems and methods are disclosed for articulating the keel skirt assembly about the hull.
Abstract:
The present disclosure provides a system and a method for efficiently converting the structure of a drilling floating platform into a structure for a production floating platform. A riser support module can be coupled to a topsides of the drilling floating platform and suspended below a moonpool or other opening through the topsides to support risers and their respective riser pull tubes, if any. The riser support module can be prebuilt and installed as a unit for example at a quayside.
Abstract:
The present disclosure provides a system and method for monitoring a floating vessel hull mooring system by determining one or more hull rotational motions of yaw, roll, and/or pitch that do not require independent knowledge of environmental conditions. The hull rotational motion of a secure and intact mooring system can be calculated and/or established experientially over time by measuring movement of the hull to characterize the hull rotational motion at given geographical positions. A compromised mooring system will result in different hull rotational motion of at least one of yaw, roll, and/or pitch. By monitoring the hull rotational motion for a given geographical position to be compared to the theoretical values (and/or previous recorded values), it is then possible to assess that at least a portion of the mooring system has been compromised and in at some embodiment indicate which portion of the mooring system has been compromised.
Abstract:
The present disclosure provides in at least one embodiment a rotatable keel skirt assembly on a rectangular-shaped keel pontoon. The rectangular-shaped keel pontoon reduces the maximum hull width by a significant percentage compared to a circular-shaped keel pontoon while maintaining the same hull motion performance. The rotatable keel skirt assembly allows the size of the pontoon to define the width of the hull during some fabrication phases of the platform, rather than the additional width of the keel skirt assembly. Thus, the outreach of the crane and other equipment can be effectively used as if the keel skirt assembly was not present. After fabrication, the hull can be moved away from the quayside and the keel skirt assembly can be rotated into position for service. Various systems and methods are disclosed for articulating the keel skirt assembly about the hull.