Abstract: The present invention provides drilling systems for drilling subsea wellbores. The drilling system includes a tubing that passes through a sea bottom wellhead and carries a drill bit. A drilling fluid system continuously supplies drilling fluid into the tubing, which discharges at the drill bit bottom and returns to the wellhead through an annulus between the tubing and the wellbore carrying the drill cuttings. A fluid return line extending from the wellhead equipment to the drilling vessel transports the returning fluid to the surface. In a riserless arrangement, the return fluid line is separate and spaced apart from the tubing. In a system using a riser, the return fluid line may be the riser or a separate line carried by the riser. The tubing may be coiled tubing with a drilling motor in the bottom hole assembly driving the drill bit.

Abstract: A subsea control module consists of three primary sections. The lower portion consists of a plate for carrying hydraulic couplings and hydraulic passages from valves to couplings. The lower portion contains a sub-assembly containing electro-optical couplings with direct sealed passages and wiring to a dry electronics chamber. The valve manifold has multiple pressure supply sources and a plurality of valves mounted therein. An outside portion of the valves are exposed so that the valves are externally accessible without disassembly of the subsea control module assembly, which facilitates an increase in accessibility and a reduction in maintenance times and costs. Electronics, wiring and solenoid valves are located in a one atmosphere, dry nitrogen purged chamber in a pressure vessel dome. The dry chamber has direct access to transducers and solenoid valves, thereby eliminating subsea cables. A mandrel extends below the device for engagement with a central locking mechanism in a receiver baseplate.

Abstract: A subsea wellhead assembly located at the sea floor that includes a subsea wellhead and a stationary blowout preventer mounted to the subsea wellhead for controlling a well during drilling. A drill pipe defines an annulus within the stationary blowout preventer. The drill pipe extends to a rotational drive mechanism on a drilling rig at the surface. A drilling head forms a seal against a drill pipe with a rotatable inner portion. The rotatable inner portion rotates with the drill pipe and prevents drilling fluid returns from flowing up the annulus around the drill pipe and prevents drilling fluid returns from discharging onto the seabed. The drilling head is mounted on top of the stationary blowout preventer. A riser extends upward from the drilling head and extends to a floating drilling rig. The riser has a lower end that connects into the drilling head below the drill pipe seal for receiving mud-returns flowing up around the annulus of the drill pipe.

Abstract: A system and methods for diverless replacement of a functional component installed on a service unit on a sea bottom-based installation is provided. The component is fitted releasably into the service unit as an insert with an externally extending maneuverable part. The replacement is carried out by a tool mounted on a remotely operated vehicle (ROV). The invention utilizes ROV supported weight compensation means for compensating the weight of the component in order to maintain the ROV in a substantially neutral buoyancy state during operations. The weight compensating means comprises a separate adapter element having the same weight as the component to be replaced. The adapter element or adapter are equipped to be releasably supported by the ROV tool. The adapter has an upper end and a lower end and a central axis extending therethrough, and a centrally extending throughgoing opening having transverse dimensions larger than the largest transverse dimension of the component.

Abstract: A movable diverter housing including a guide adapted to be mounted to the underside of a drill floor on a drilling rig and a diverter housing adapted to move in engagement with the guide.

Abstract: A riser tensioner system for applying a substantially constant tensioning force to a riser and allowing a floating platform to move within a given range along a longitudinal axis of the riser. The system includes a plurality of tensioner assemblies each of which are coupled to the riser and to the platform. Each of the tensioner assemblies includes an upper member, a lower member, a connecting member coupled to the upper and lower members, and intermediate members coupled to the upper and lower members at a point intermediate the ends of the upper and lower members. At least one of the upper member, the lower member, and the intermediate members are adapted to provide a constant tensioning force. The arrangement of the upper member, lower member, connecting member, and intermediate members further provide a linkage whose centerline in angularly spaced from the longitudinal axis of the riser by a substantially constant amount throughout the range of motion of the linkage.

Abstract: A subsea well assembly has an antirotation device to prevent rotation of an inner wellhead housing within an outer wellhead housing. A number of slots are formed in the upper rim of the outer wellhead housing. The slots have open upper ends. A number of pins are mounted to the exterior of the inner wellhead housing. Guide surfaces extend upward from the slots to guide the pins as the inner wellhead housing is lowered into the outer wellhead housing. The pins locate in the slots to prevent rotation.

Abstract: A protective cap (12) can be run onto and retrieved from a subsea wellhead (10) from a floating service vessel. Slidably mounted shear pins (32) in the cylindrical wall (14) of the protective cap (12) allow the cap to be attached by a downward push. Retrieval of the protective cap (12) involves an overpull on the drill string that is sufficient to shear the pins (32) in the cylindrical wall (14).

Abstract: A running tool for use with a subsea well guide base when drilling from a floating drill ship is designed to be releasably detached without rotation so that the tool can be uncoupled at the surface upon completion of the guide base running procedure. The running tool is attached to the guide base by threaded elements which are designed to strip when a predetermined upward force is exerted on the running pipe string to which the tool is integrally connected thereby permitting retrieval of the tool by the running string.

Abstract: A retrievable guide base and gimbal unit for a subsea well, and a tool for use with a pipe running to retrieve the guide base and gimbal from the subsea wellhead.

Abstract: An offshore oil production and mooring system comprises a subsea well head production system connected to a subsea base located on the sea bed. A subsea restraining buoy is located at a position below the sea surface but above the sea bed. The buoy is pivottally connected by a flexible lower support line to the subsea base and by a flexible upper support line to a buoyant riser endpiece adapted for connection to a loading vessel. The endpiece is located in its rest position at a position below the sea surface but above the sea bed and is anchorable to the sea bed. A flexible production riser rises from a subsea connector to the production system to the subsea restraining buoy and is supported by the lower support line. The riser then passes over the buoy and so to the riser endpiece, this section of the riser being supported by the upper support line.

Abstract: A system for handling a reeled tubing including a guide, a shear for cutting the tubing and a tubing injector including upper and lower strippers and guides and an enclosure for the injector. The enclosure in one form excludes sea water in an open bottomed enclosure and the other maintains pressure in a completely closed enclosure.

Abstract: A subsea wireline lubricator comprises in sequence (a) a stuffing box, (b) at least one blow-out preventer, (c) a riser, (d) a foot valve and (e) a connector for connection to a subsea well head assembly.The lubricator permits wireline access to subsea oil wells without the need for a conventional tensioned riser.

Abstract: A fluid handling system with an injector in an enclosure and at least one stripper with upper and lower cup-shaped receptacles and resilient seals in the receptacles together with a fluid relief port between the receptacles for recovering fluid passing the seals.

Abstract: A system for oil well drilling and completing operations in deep water which allows an oil well drilled in deep water to start producing, the operations being conducted from a dynamically placed vessel, comprising: providing a permanent guide base (9) on the sea bottom containing a high pressure housing (13) having an upper free end (15) adapted to receive safety, drilling, and production (completion) equipment, the upper free end of the high pressure housing being covered by a protective cover (17) having an external conical part (18), the permanent guide base (9) also having attached thereto, by means of a releasing device, a releasable guide-funnel (10) which covers and protects the upper free end of the high pressure housing during drilling of the well but which prevents the production equipment from being installed because of its size and shape; withdrawing the releasable guide-funnel, after drilling operations are finished, by means of a remote control vehicle which activates the releasing device, thus

Abstract: A method and apparatus for injecting coiled tubing into a submerged well. The end of a coiled tubing is latched in a tubing injector and the tubing and injector are lowered through a body of water together. The injector is latched to the well and the injector moves the coiled tubing through the well. The injector weight is exerted on the tubing during movement through the body of water.The injector may be contained in a bell type or complete enclosure and fluid in the enclosure is maintained at approximately the external pressure.The injector may be connected to a shear, a stuffing box, and a tool receiver.

Abstract: A process for oil well drilling and completing operations in deep water which allows an oil well drilled in deep water to start producing, the operations being conducted from a dynamically placed vessel, comprising: providing a permanent guide base (9) on the sea bottom containing a high pressure housing (13) having an upper free end (15) adapted to receive safety, drilling, and production (completion) equipment, the upper free end of the high pressure housing being covered by a protective cover (17) having an external conical part (18), the permanent guide base (9) also having attached thereto, by means of a releasing device, a releasable guide-funnel (10) which covers and protects the upper free end of the high pressure housing during drilling of the well but which prevents the production equipment from being installed because of its size and shape; withdrawing the releasable guide-funnel, after drilling operations are finished, by means of a remote control vehicle which activates the releasing device, thus

Abstract: Method and apparatus for retrieving a running tool/guideframe assembly without the use of winch wires. A portion or each guidepost assembly can be unlatched from the seafloor-mounted template to permit that portion to be retrieved using the guidewires. The unlatchable portion of the guidepost system is formed with a load support that engages and supports the running tool/guideframe assembly so that the assembly is retrieved concurrently with the unlatchable portions of the guidepost assemblies.

Abstract: A sea bed oil producing and processing complex has a template with three bays housing pairs of modules, viz, well, gas and oil production modules. The complex includes a separator for separating oil and gas and a pump for the produced oil, and bars having pipework to carry fluids between the pairs of modules and to despatch separated gas and oil. Saddles may carry fluids across between individual modules of a pair and the complex may have facilities for artificial lift, water injection, chemical fluid injection and for test fluids. Multiples of the three bays and pairs of modules may be within a single template and a number of modules may surround a central piping template. The complex can be services and maintained in a diverless mode using a monohull vessel and an ROV.

Abstract: The field of crude oil exploitation on a sub-marine site. The station comprises a platform 1 of octagonal shape carried by a central column 2 anchored in the ground on which is fixed an effluent collecting module 5. Stacked on the said module is a central control module 60. Fixed in overhanging fashion on six sides of the octagon are frames 10 to 15 adapted to overhang drilling wells and each carrying a production head 30, 40. On the other two sides of the octagon, fixed by means of frames, there are an umblical head 80 and a connecting module 70 for the discharge of effluent.This arrangement makes it possible to bring a certain number of wells close to the platform and so shorten the distances between the modular units.

Abstract: A modular near-surface completion system that positions the production wellheads in a quiescent zone beneath significant wave activity yet within reach of divers for maintenance and inspection. Each subsea well is provided with (a) its own riser, (b) a riser tensioning buoy and (c) a production well tree mounted atop the riser buoy. Produced fluids are transmitted from the well tree to the floating production platform by means of flexible risers suspended in a catenary loop of sufficient length to permit the platform to be maneuvered to position it for drilling or workover of any of the plurality of templates it services.

Abstract: A subsea pumpdown tool launcher is provided which permits pumpdown operations without requiring riser access from the surface. The launcher includes an entry valve connected to an upper connection of a fluid circulation line which is, in turn, connectable to a pump. An unrestricted riser section is connected to the lower connection of the circulation line. The bottom of this riser section attaches to the top of a second valve for the exit or entry of a pumpdown tool to or from a subsea wellhead. The bottom of the second valve is connected to the top of a lower connection of the fluid circulation line. The bottom of the lower connection is connected to the top of a subsea wellhead assembly.

Abstract: Connectors, particularly remotely operated connectors used to connect underwater well members under large clamping forces, are provided with rigid rolling antifriction elements engaged between a camming surface and a cam follower surface for converting axially directed operating motion into radial movement of a contractible and expansible annular locking means.

Abstract: Connector, particularly for use in underwater well installations, for securing members together under large clamping forces. The connector is characterized by two successive stages of actuation of a locking means, typically a split ring or set of arcuate segments, with the actuating force of the second stage being applied by camming surfaces via low friction means to establish a high compressive preload without use of especially large power devices.

Abstract: This riser has a central pipe connected to an underwater installation through a flexible assembly, and a plurality of satellite pipes connected to corresponding tubes of the underwater installation through a plurality of hoses each arranged along an helical winding. Upper and lower fastening means secure these hoses to the upper and lower parts of the flexible assembly and maintain the ends of each connecting hose in the extension of the helical winding.

Abstract: A template for spacing a submarine structure such as an anchor block or a guide base for a second underwater well alongside an existing underwater well comprises a beam attached at one end, by means of a hinge, to a lowering guide which can be threaded over and be lowered along two guide wires of the first well, and at the other end by a remote-controlled release mechanism to the submarine structure such as the anchor block itself or a guide base for a second well.The beam, with such a submarine structure attached, is lowered down the guide wires while held in a vertical configuration, and is then swung into a generally horizontal configuration at the sea bed.

Abstract: This invention concerns a seabed device to support tubing connected to a wellhead.The device comprises a flange at the bottom end of the tubing, fitting into a rigid frame attached to and detachable from a framework located on the seabed, the said flange being connected to the wellhead by the same number of flexible pipes as there are passages in the tubing, with a connection-disconnection device to attach these flexible pipes to the wellhead.This device relieves the wellhead of stresses transmitted by the tubing.