Abstract: An acoustic underwater navigation system is disclosed. For instance, an underwater receiver determines its position using signals broadcast from an array of acoustic transmitters located near the surface. The position of the array is measured using global positioning system (GPS) technology and the transmitters collectively produce an acoustic signal in which the position and attitude of the array and the GPS time of transmission are encoded. An underwater receiver which is synchronized with the GPS time uses the transmitted position and attitude of the array and the transmission time information to calculate its position.

Abstract: A template for use in positioning subsea wellbores that has a drop away funnel that extends laterally from the template. The drop away funnel is used to locate a piling adjacent the wellbores and is selectively detached from the template after installing the piling. A tang and clevis type assembly mounts the drop away funnel to the template, where the tang and clevis are coupled together with a main stud. The main stud is oriented substantially parallel with an axis of the drop away funnel; so that when the stud is removed, the drop away funnel can decouple from the template and slide axially downward along the piling.

Abstract: A mobile drilling system comprising a top member with a drilling rig positioned thereon. The top member is removably engaged with a foundation member. The foundation member comprises a tower. The top member is moveable and adapted to be elevated out of the water for placement on top of the tower. The tower is preferably of concrete and extends out of the water and above any ice. A method is also described by which the top member is elevated out of the water either by jacking down legs or lifting by interaction with the tower.

Abstract: A method for installing risers so they extend from a FPU (floating production unit) to multiple subsea hydrocarbon wells of an oil field, which avoids damage to the pipe sections and that is economical. As pipe sections are connected to a near end (56) of a pipe string portion (68B-68D) that lies at the FPU, a tug boat (30) pulls the far end (65) of the pipe string toward a well head. Initially, a long pull line (34) extends from a winch (32) on the tug boat, in a double catenary curve to the far end of the pipe string. The winch is operated to shorten the pull line until the pipe string extends in a double catenary curve (60). Tension in the pipe string is maintained at a proper level during installation by maintaining the near end portion of the pipe string so it extends at a near end angle (70) to the vertical that continually lies within a predetermined range, such as from 3° to 12°.

Abstract: A ram tensioner system with a deck mountable frame having an upper portion and a lower portion connected by a plurality of cylinder sleeves and at least one guide post sleeve. A guide post engages the guide post sleeves, and an individually replaceable modular cylinder is in each cylinder sleeve along with at least one individually removable seal gland that is lubricated by a hydraulic power unit, and a slidable rod engaging each of the cylinders. The slidable rods can be attached to the tension deck with a tension ring to engage a riser and provide movable tension to the riser.

Abstract: One or more embodiments of a floating vessel for supporting well head surface equipment that has a deck operatively disposed on the floating vessel. The floating vessel can include a ram tensioner system positioned between the well head surface equipment and the deck. The ram tensioner system can include push up ram style tensioner system with a deck mountable frame having an upper portion and a lower portion connected by a plurality of cylinder sleeves and at least one guide post sleeve.

Abstract: A combined piloting method of remote operated underwater vehicles includes: connecting, to a vertical profile, a constraint device including at least two arms arranged at a reciprocal fixed angular position, each of the at least two docking arms including at a first end a device for the hooking of a remote operated underwater vehicle, the at least two docking arms being constrained at one of their second ends to a device for the sliding and rotating hooking to the vertical profile; connecting at least two remote operated vehicles to the constraint device; detecting the position of the overall structure consisting of the constraint device and remote operated vehicles; detecting the orientation of each of the remote operated vehicles; receiving data relating to the position and orientation to be reached; determining the power required by each remote operated vehicle; and transmitting related commands to each vehicle.

Abstract: Apparatus includes a seal head having first and second ends and a sidewall having an internal diameter. The first end of the seal head is open to the environment, and the second end is closed to the environment by an end cap. The seal head includes an aperture configured to accommodate a subsea source. A tubular seal head extension is fluidly connected to the seal head end cap. The seal head extension has an external diameter, an external surface, and a length. A movable element having first and second ends and a sidewall structure having an internal diameter sufficiently larger than the external diameter of the extension forms an annulus between the movable element and the extension. The movable element first end opens to the environment, while its second end is closed by an end cap defining an exit fluidly connectable to a subsea collection system.

Abstract: Floating systems for well operations are disclosed with a height-adjustable crown assembly movably connected to a derrick; in one aspect, movable within the derrick by movement apparatus; and, in one aspect, movable with a motion compensator. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).

Abstract: A drill ship is provided for conducting subsea operations, including intervention, maintenance and workover operations. The ship includes a hull having a substantially wide beam-to-length ratio and a deckspace. An automated system for handling tubulars and risers is mounted to the deck space, along with a pipe racking system. The deckspace includes a heavy-lift heave crane for handling seafloor operations and a medium duty crane mounted over the deckspace. The ship is configured to provide heavy lift subsea construction operations including 16-inch riser well intervention and workover programs, connected riser completion operations, and riserless tophole drilling and casing operations. The ship is also able to perform connected riser remedial drilling and slim hole well construction. The ship maximizes environmental efficiency in both construction and use, and provides a stable and safe work and living environment for operations personnel.

Abstract: A subsea intervention system is disclosed comprising a floating vessel and a source of coiled tubing at the floating vessel. The system includes a seabed installation including a wellhead and compliant guide having one end operatively connected to the floating vessel and the second end operatively connected to the seabed installation. The compliant guide provides a conduit between the floating vessel and the wellhead for the coiled tubing. At least one injector is present at the floating vessel for inserting the coiled tubing into the compliant guide, and a carousel is proximate the wellhead which comprises a plurality of chambers with intervention tools in at least two of those chambers. The system may also include a plurality of sensing units that are disposed at spaced intervals along the compliant guide to monitor various aspects of the compliant guide and to transmit that information to a repositioning system.

Abstract: A system for supporting multiple-well-site, offshore, hydrocarbon-bearing fields, each well-site has one or more wells. In general, the system first comprises a floating vessel that is relocatable from a first subsea well-site to a second subsea well-site. The system also comprises two separate systems: (1) an operations control system for providing subsea well-site operations such as power and communications; and (2) an intervention system for conducting intervention services to an individual subsea well such as workover services and maintenance services. The operations system may provide control to wells and other subsea equipment at either the first well-site or the second well-site, regardless of the location of the floating vessel. The intervention system may provide workover and/or maintenance to subsea equipment or individual wells at the well-site at which it is located.

Abstract: A method of installing equipment subsea comprising the steps of: assembling the equipment within a frame; submerging in the sea at least a part of an assembly comprising the frame and the equipment; coupling the at least partially submerged assembly to a vessel; transporting the at least partially submerged assembly proximate a subsea installation site; coupling the assembly to an installation device; and installing the equipment at the installation site using the installation device. A frame for supporting equipment is also disclosed wherein the frame is shaped to match the dimensions of the equipment to be supported. The frame comprises at least one clamp having a first half clamp member for releasably engaging a second half clamp member of a second structure and a full clamp member for clamping around and supporting the equipment. The first half clamp member and the full clamp member can be integrally formed.

Abstract: The invention relates to a vessel (1) provided with a deck (2) and with a device (3) for removing and/or installing a sub-structure (4) of a drilling or production platform, wherein said device comprises a supporting structure (5) which is capable of tilting movement in a direction transversely to an edge (6) of the deck (2), hoisting means (7) connected to said supporting structure for hoisting said sub-structure, and supporting means for supporting said sub-structure mainly during tilting movement of said supporting structure, wherein said supporting means are provided separately from the supporting structure and capable of tilting movement with respect to the edge of the deck.

Abstract: The invention relates to apparatus for controlling the flow rate of a fluid in tubing (4), said apparatus (5) comprising at least one hole (7) passing through the wall of said tubing and a moving shutterjacket (8) mounted to engage said hole. According to the invention, said apparatus further comprises deflector means (9) covering said jacket and said hole so that said deflector means directs the fluid through the wall of said tubing.

Abstract: A system and method autonomously clears obstacles and mines from an approach lane. A ship is distantly located from an approach lane spanning a surf zone and beach portion, and the ship has operator control station software in an onboard computer. At least one system delivery vehicle having a storage bay and propulsion system transits from the ship to the approach lane in response to instructions from the operator control station. A line charge is disposed in each bay and has one end coupled to the system delivery vehicle. A line charge delivery vehicle in the bay is connected to another end of the line charge to pull the line charge from the bay and emplace it in a straight path in the approach lane in response to instructions from the operator control station. Explosives in all line charges are detonated to clear the approach lane.

Abstract: Hybrid riser configuration comprising a plurality of steel riser pipes substantially inserted in aluminium guide conduits, with buoyancy means and tethering tension means, the guide conduits and riser pipes being rigidly connected to a base anchored to the ocean floor. The guide conduits serve as the tethering tension means and as radial constraint for the respective riser pipe therein to allow the riser pipe to buckle in elastic deformation (Euler) to form a spiral when expanding due to service pressure and temperature. A method for installing the riser configuration is also disclosed.

Abstract: A subsea hydrocarbon reserve is exploited by intially drilling a first well (4) from a floating drilling vessel (2). A tree (8) is then installed on the well (4) and a production riser (10) is established between the well and the vessel for transferring production fluid from the first well (4) to the vessel (2) from where an off-loading hose (12) conveys the production fluid to a tanker (18). Production fluid is then extracted from the first well (4) via the production riser (10) which is of sufficient flexibility and length to permit the drilling vessel (2) to move between appropriate locations to drill further wells (4′, 20).

Abstract: A method and a system for testing a borehole in an underground formation by the use of so-called closed chamber testing. When carrying out the method, a test or production pipe (5) is carried down the borehole, where the test pipe can be closed at its upper end and at its lower end is provided with a downhole assembly (6) comprising equipment for testing of fluid flow from the formation (3), the annulus (23) between the test pipe (5) and a casing (20) in the borehole being shut off during the test by a gasket (22) at a desired depth, and fluid from the formation being allowed to flow through the test pipe (5) to a collecting tank (9) coupled to the test pipe via a flow head (4) at the upper end of the test pipe (5).

Abstract: A subsea system is provided for producing a number of subsea wells which may be arranged in groups. Each of the groups of subsea wellheads is connected to deliver production flow to a subsea manifold and each subsea manifold is connected to deliver production flow to a production riser. A plurality of production risers each being connected to receive production flow from one of said subsea manifolds extend from the subsea manifolds for groups of wells. A deep draft floating spar is located generally above the subsea wellheads with mooring lines and has a production platform located above the sea surface and has buoyancy and ballast chambers to control floatation. The spar structure defines a riser bore receiving the production risers extending from the subsea wellheads to the production platform. The spar is also capable of being shifted laterally by its mooring lines for positioning above a selected well to thus permit well intervention activities as needed.

Abstract: A method of extending the working range of a main platform installation for oil deposits at sea involves:(1) positioning a temporary floating station at a location distance from the main platform installation and near to an oil deposit having small individual production capacity;(2) connecting the floating station with at least one well head of said oil deposit;(3) bringing up multi-component effluents from the at least one well head and pumping the effluents to the main platform installation;(4) when production of the effluents from said deposit ends, removing the floating station; and then(5) repositioning the floating station at at least one other oil deposit located at a distant location from said main platform installation to work the at least one other deposit. Also a facility for carrying out this method as described.

Abstract: A method of extending the working range of a main platform installation for oil deposits at sea involves:(1) positioning a temporary floating station at a location distance from the main platform installation and near to an oil deposit having small individual production capacity;(2) connecting the floating station with at least one well head of said oil deposit;(3) bringing up multi-component effluents from the at least one well head and pumping the effluents to the main platform installation;(4) when production of the effluents from said deposit ends, removing the floating station; and then(5) repositioning the floating station at at least one other oil deposit located at a distant location from said main platform installation to work the at least one other deposit. Also a facility for carrying out this method as described.

Abstract: A method is described for conducting well operations from a floating platform that may be moved to various locations above subterranean formations. Marine risers that have been previously connected to the platform flex sufficiently to allow this movement. The mobility of the platform allows well drilling, completion, producing, and workover activities to be conducted simultaneously through the risers attached to the platform. The mobility of the platform also allows new wells to be drilled at more preferable locations than those that would be available from a fixed bottom supported well template.

Abstract: A subsea drilling template has a plurality of drilling guides disposed at various angles relative to the plane of the template. The drilling guides cause angular deviation of the drill string passing into the guides resulting in wide spacing of the boreholes drilling through the template. The widespread boreholes allow efficient production of shallow subsea hydrocarbon producing formation without the need of satellite wells.

Abstract: Method and apparatus for use in drilling a well from a floating vessel by means of a riser which connects the vessel's drilling equipment to a wellhead assembly adjacent the ocean floor. Braking apparatus is provided which is capable of arresting the vertical motions of the drilling riser and of securing the upper end of the riser to the vessel whenever the riser is disconnected from the wellhead.

Abstract: Apparatus for use in drilling a well from a floating vessel by means of a riser which connects the vessel's drilling equipment to a wellhead assembly adjacent the ocean floor. The riser is capable of being disconnected from the wellhead assembly and having the motion of its upper end arrested and subsequently secured to the vessel. The present riser braking clamp apparatus comprises braking elements integrally carried by the telescoping joint located at the upper end of the riser. Actuation of these braking elements prevents further telescopic movement of the telescopic joint, thereby preventing movement of the riser upper elements relative to the vessel.

Abstract: Apparatus and method for use in drilling a well from a floating vessel by means of a riser, which connects the vessels drilling equipment to a wellhead assembly adjacent the ocean floor. The riser is capable of being disconnected from the wellhead assembly, and having its upper elements locked to the vessel. This allows the riser to be suspended from the floating vessel, or permits maintenance of the normal riser motion-compensating and tensioning equipment. Riser locking apparatus is employed which comprises selectively positionable moveable locking beams adapted to be remotely actuated to lock the upper elements of the riser to the vessel, thereby preventing lateral or vertical movement of the riser relative to the vessel after the lower end thereof has been disconnected from the wellhead assembly.

Abstract: An oil production system for producing oil at an offshore location comprises a floating storage vessel to receive the produced oil, the vessel having means for dynamic positioning and being connectable to a subsea well head by a riser and having means for separating the associated gas from the produced oil and employing the separated gas as fuel for the dynamic positioning.Re-entry of the subsea well is effected by providing the riser with means for effecting a simultaneous stab connection with the production bore and hydraulic control system lines without orientation.