Abb Lummus Global Inc.

Deepwater Marine Technology L.l.c.

Edward Huang

Jun Zou

Shihwei Liao

Bambang A Sarwono

Bruce Zurbuchen

Vince Giorgi

Shaji Samuel

John Allen

John Chianis

Clay F Anderson

Frank Shih-Fai Chou

Ngok W Lai

Thomas W Clapp

A tension leg platform is secured to the sea floor with a plurality of tendons, each of the tendons being in tension due to buoyancy of the platform. The tendons are made up of joints of pipe secured together to define a hollow interior sealed from entry of sea water. A lower section of the joints of pipe of each of the tendons has smaller inner and outer diameters and greater wall thicknesses than an upper section of the joints of pipe. Bulkheads are sealed within the interior of the upper and lower sections of the joints of pipe of each of the tendons. The bulkheads are spaced apart from each other along the lengths of the upper and lower sections of the joints of pipe to define separate compartments sealed from each other.

Stepped tendon with sealed bulkheads for offshore platform

A tendon for an offshore floating platform has a tubular section formed of joints of steel pipe secured together. The tubular section has an interior sealed from sea water to provide buoyancy. A composite fiber section is secured to a lower end of the tubular section. The composite fiber section is formed of non metallic fibers and has a solid interior.

Hybrid composite steel tendon for offshore platform

A temporary stability module and method for marine structures during construction, transportation and installation is taught. The device and method permit the structure, including platforms, deck and equipment to be constructed in an upright position, towed to an ocean installation site, and installed by ballasting the structure or temporary stability module and subsequent removal of the module.

Temporary floatation stabilization device and method

A lateral mooring system for tendon-based platforms is disclosed, which provides reduced installation and/or operational cost associated with the installation and operation of an extended-base tension leg platform. The lateral mooring system includes a plurality of mooring lines that provide lateral support to the platform in mild metocean conditions, but may have application in more severe oceanic condition. A method for installing the system on the platform and a method for drilling wells on a offshore site.

Tension leg platform having a lateral mooring system and methods for using and installing same

A marine buoy for the offshore support of subsea production and drilling activities that has a closed-bottomed base section with a solid ballast and variable ballast chambers, a chamber in the base section for storing equipment and supplies, and an upper section with a smaller cross-sectional area than the base section having an elevator shaft leading from the top of the upper section to the chamber in the base section. The upper section supports a deck for housing process equipment for operations that the marine buoy is supporting.

Marine buoy for offshore support

An offshore well platform is towed in an upright condition to a well site by the use of a temporary flotation device. The flotation device mounts to a portion of the platform and is partially submerged, increasing the ability and buoyancy of the platform. At the site, the engagement of the flotation device shifts to a deploying position. In the deploying position, the ballast of the platform is increased to cause it to more deeply submerge. The flotation device remains at least partially surrounding the platform and floating while the platform moves downwardly relative to it. This provides lateral support if needed to prevent heeling while being submerged. The flotation device is disengageable from the platform when the platform is fully submerged.

Floating stability device for offshore platform

An extended-base tension leg substructure, an offshore platform supported on the substructure and a method for supporting an offshore platform on the substructure are disclosed, where the substructure includes a plurality of support columns disposed about a central axis of the substructure and interconnected by at least one pontoon. Each column comprises an above water and submerged portion. The substructure also includes a plurality of wings or arms radiating from the columns and/or the pontoons, each wing fixedly or removably securing at least one tendon extending from a wing to an anchor on the seabed. The substructure includes an open, wave transparent central zone for improved access to well-related equipment, conduits or the like and the wings minimize translational movement and rotational flex in the substructure reducing fatigue in the tendons and their connections.

Extended base tension leg substructures and method for supporting offshore platforms

An exemplary floatable vessel is described having an upper tower section with a reduced diameter or width and an affixed lower base section having an enlarged diameter or width. The lower section contains weighted ballast distributed upon its lower floor. The lower section also includes flotation tanks which can be filled with air to raise the vessel in the water such that portions of the lower section are raised above the water line. Alternatively, the flotation tanks can be flooded to dispose the lower section and a portion of the upper section below the water level. The upper tower section of the vessel supports a deck structure upon which rig components can be constructed or secured. The tower section includes flotation tanks as well. In preferred embodiments, these tanks are variable tanks that can be partially filled with air and partially flooded with water. The vessel defines a central chamber within which drilling risers are contained and suspended from the deck structure of the vessel downward toward the sea floor. One or more pneumatic supports are provided which assist in securing the riser and absorbing energy from movement of the platform. The floating vessel can be constructed and transported in a upright or vertical orientation so that it does not need to be upended prior to mooring at its intended location. In addition, structures such as rig components may be placed atop the tower portion prior to or during transportation of the vessel. During transportation by towing, the flotation tanks of the lower section are filled with air so that the lower section is partially raised above the surface of the water. The vessel is placed into its installed position by flooding the flotation tanks of the lower section to cause the lower section to become submerged.

Growing community of inventors

Houston, TX, United States of America

Edward Huang