Abstract: A running string for a subsea completion comprises an upper section (70) which may be a coiled tubing (CT) injector unit as shown, or a wireline lubricator (FIG. 8). A lower section (60) provides wireline/CT access to production/annulus bores of a tubing hanger (not shown) attached to tubing hanger running tool (62). A flow package (64) in the lower section (60), together with BOP pipe rams (86) and annular seal (88), directs production and annulus fluid flows/pressures to the BOP choke/kill lines (78/76). The upper and lower sections allow installation and pressure/circulation testing of, and wireline/CT access to, a subsea completion, without the use of a high pressure riser.

Abstract: In the drilling of a well, a dedicated drilling wellhead (520) mounted at the top of the casing cluster whilst the well is being drilled. At the end of drilling, a seal ring or sleeve (534) which during the drilling phase has the function of an annular sleeve isolating the well bore pressure from the production annulus space (540), is manipulated into an alternative position in which it acts to block the annular space (540) thereby acting as a temporary abandonment seal. A further plug seal is fitted in the well bore. The well is now temporarily sealed and the drilling wellhead can then be removed and can be reused on another well during the drilling phase of that well. A production wellhead (550,556) which has a cantilever christmas tree fitted on its side over a production wellhead (557) which can accept a conventional christmas tree on top is then fitted on to the casing hanger cluster.

Abstract: A standard ROV/manual gate valve operating mechanism is used to move a bore selector between the production and annulus bores of a completion. The ROV operation could be via torsion or linear action. The positioning of the selector may be hydraulically linked to the functioning of retainer valves. Alternatively, the operating mechanism may be for one of the retainer valves, with a mechanical linkage for actuation of the bore selector.

Abstract: The well intervention system of the invention is a novel subsea deployed wire line, “stiff wire” (conventional wire-line located inside reeled tubing or embedded in the tubing wall), coil tubing, or reeled pipe unit landed on the existing subsea wellhead assembly or tree, wherein the unit includes as an additional novel component a “carousel” tool caddy. The carousel is utilized to allow the remote change-out of multiple tool strings that are included in the carousel prior to deployment, thereby eliminating the need for a “riser” conduit to the surface or the need to trip tools through the riser column for tool replacement. The subject invention also includes an improved method for conducting a well intervention activity, wherein the method includes the step of selecting a tool for the well intervention activity from a carousel tool caddy located in close proximity to the well.

Abstract: A subsea production system and method includes a wellhead field having multiple wellheads and utilizes a stackable guide funnel system for sequential tying back of those wellheads. A storage frame retains several guide funnels that are nestably stacked one upon the other. The guide funnels may be sequentially removed from the frame by a riser connector having a complimentary latching mechanism. The frame is made up of a plurality of guide members that are secured to the exposed tubular conductor of a wellhead. A pair of annular rings surrounds portions of each of the guide members. The upper end of the frame is outwardly flared to assist in landing of the riser connector. The stacked guide funnels are prepositioned at one or more central locations upon the sea floor. The guide funnels are configured at the central location to permit sequential retreival. A riser having a riser connector is lowered to the central location. The riser connector latches onto the uppermost guide funnel within the frame.

Abstract: A riser connector is provided for connecting a riser to a wellhead assembly having a bore therethrough. The connector includes a housing having a first and a second end. The first end of the housing has an opening and is adapted for mounting to the wellhead assembly with the opening in communication with the bore of the wellhead assembly. The second end has a first opening connectable to the riser having a diameter at least the same as the inner diameter of the riser, and a second opening, having a diameter at least substantially the same as the diameter of the bore of the wellhead assembly. The housing further includes a first conduit connecting the opening in the first end of the housing to the first opening in the second end of the housing, and a second conduit connecting the opening in the first end of the housing to the second opening in the second end of the housing. In use, first well operations are conducted through the riser in the conventional manner.

Abstract: An underwater well system in which an initially vertical drilling riser conduit (5A) is fixed by a template at the seabed in a non-vertical orientation. Drilling is carried out through wellhead in the template which also includes a valve tree allowing the production fluid to be brought to the surface along a line separate from the drilling riser conduit. The template may be a junction template allowing several wells to be drilled from a single template, or allowing the template to be connected by one or more drilling conduits to further templates such that a wide area of the seabed can be covered for a single drilling riser conduit.

Abstract: A controls bridge for a flow completion system which comprises a tubing spool having a production outlet, a tubing hanger having a production bore that communicates with the production outlet and at least one service and control conduit extending therethrough, and at least one external service and control line that terminates near the tubing spool, the controls bridge comprising a first body portion; a mechanism for securing the first body portion to the top of the tubing spool and/or the tubing hanger; at least one first coupling member which is adapted to engage a second coupling member that is mounted in the service and control conduit; at least one third coupling member which is adapted to engage a fourth coupling member that is connected to the external service and control line; a bridge line which is connected between the first coupling member and the third coupling member; a first actuator for moving the first coupling member into engagement with the second coupling member; and a second actuator for mo

Abstract: The well intervention system is a subsea deployed wire line, “stiff wire” (conventional wire-line located inside reeled tubing or embedded in the tubing wall), coil tubing, or reeled pipe unit landed on the existing subsea wellhead assembly or tree, wherein the unit includes as an additional novel component a “carousel” tool caddy. The carousel is utilized to allow the remote change-out of multiple tool strings that are included in the carousel prior to deployment, thereby eliminating the need for a “riser” conduit to the surface or the need to trip tools through the riser column for tool replacement. A method for conducting a well intervention activity, wherein the method includes the step of selecting a tool for the well intervention activity from a carousel tool caddy located in close proximity to the well. The invention system may also be employed in a similar manner to conduct repair or surveillance operations for pipelines or flowlines having flow control manifolds.

Abstract: The well intervention system of the invention is a novel subsea deployed wire line, “stiff wire” (conventional wire-line located inside reeled tubing or embedded in the tubing wall), coil tubing, or reeled pipe unit landed on the existing subsea wellhead assembly or tree, wherein the unit includes as an additional novel component a “carousel” tool caddy. The carousel is utilized to allow the remote change-out of multiple tool strings that are included in the carousel prior to deployment, thereby eliminating the need for a “riser” conduit to the surface or the need to trip tools through the riser column for tool replacement. The subject invention also includes an improved method for conducting a well intervention activity, wherein the method includes the step of selecting a tool for the well intervention activity from a carousel tool caddy located in close proximity to the well.

Abstract: A method to set a hollow device into an undersea flow pipe uses a flexible pig driven by a flow flowing into said flow pipe to displace a hollow device to a point where a stop means halts a displacement of said hollow device, thereby setting said hollow device into position. A method to retrieve a hollow device into an undersea flow pipe uses a flexible pig driven by a flow flowing into said flow pipe to retrieve said hollow device from a location where said hollow device operates halted by a stopping means.

Abstract: An apparatus for controlling a blowout preventer stack. The apparatus comprises a control pod having a plurality of direct operated solenoid valves in electronic communication with a surface controller through one or more dedicated electronic control wires. The solenoids translate electronic control signals from the controller into hydraulic control signals that are in communication with a hydraulically operated pilot valve to cause delivery of hydraulic fluid from a power fluid source to a critical function of the blowout preventer stack (i.e., closing of a blowout preventer). The system also provides a plurality of hydraulically operated pilot valves that deliver hydraulic fluid from a power fluid source to a non-critical function of the blowout preventer stack upon receiving a hydraulic control signal directly from the controller through the umbilical.

Abstract: A method for retrieving a subsea pod from a lower marine riser package platform by connecting a buoyant pod retriever to the subsea pod and raising the subsea pod to the surface. In certain aspects, such a method is accomplished without an interruption of associated subsea drilling operations and/or without disconnecting the lower marine riser package from an associated subsea stack. Such a method, in certain aspects, includes: positioning a retrieval module above the pod container, the retrieval module having a pod holder releasably connected thereto; disconnecting the pod holder from the retrieval module; lowering the pod holder to the pod container and releasably connecting the pod holder to the pod container; releasing the pod container from the subsea lower marine riser platform; raising the pod holder to the retrieval module and releasably connecting the pod holder with the pod container to the retrieval module; and raising the retrieval module with the pod container to a location at the surface.

Abstract: A slimbore marine riser and BOP are provided for a subsea completion system which includes a tubing spool secured to a wellhead at the sea floor. The tubing spool has an internal landing profile for a reduced diameter tubing hanger which is arranged and dimensioned to pass through the bore of the riser and BOP at the end of a landing string. The tubing hanger, arranged and designed to be sealingly positioned in the tubing spool landing profile, has a production bore and a relatively large multiplicity of electric and hydraulic passages which terminate at a top end of the hanger with vertically extending electric and hydraulic couplers. A passage is provided through the body of the tubing spool which provides communication from above the tubing hanger to the well annulus below the hanger. A remotely controllable valve is placed in the annulus bypass passage.

Abstract: A one-trip system for removing casing from a wellhead is described. The string includes a cutting device spaced at the required depth and a grappling device above it at the appropriate location. A swivel tool, such as a marine swivel, is used in conjunction with a seal-pulling assembly so that after cutting the casing, the seal assembly can be pulled without an additional trip into the well. The grappling device or spear can be hydraulically actuated to grab the casing for removal from the wellbore. The spear features a drop-in restrictor which allows sufficient flow during cutting operations with a mechanical cutter without actuating the spear, while at the same time allowing actuation of the spear by circulation after dropping in the restrictor after the casing section has been cut.

Abstract: A deep ocean drilling system is disclosed for drilling offshore wells in extremely deep water using smaller and more economical drilling vessels. The system utilizes a reduced diameter drilling riser that reduces the size and cost of conventional floating drilling unit. The reduced diameter drilling riser is detached from the blowout preventer stack and repositioned and attached to a mud return assembly. Large diameter casing is lowered into the wellbore outside of the reduced diameter riser. Thereafter, the reduced diameter drilling riser is released from the mud return assembly and repositioned over and reconnected to the blowout preventer stack.

Abstract: A method of intervention on the seabed (F) using a free end of one riser (24) originating from a semi-submersible platform (10) designed for producing oil from a deposit, at a number of distinct intervention points (30, 32), includes the following successive steps: tethering the platform (10) to immobilize it in a position floating over the deposit; installing the riser (24) connecting the floating platform (10) to the seabed (F) for intervention at a first intervention point (30); carrying out an intervention at the first intervention point (30); disengaging the free end of the riser (24) from the first intervention point (30), while keeping this end submerged; moving the free end of the riser (24) with respect to the seabed (F) towards a second intervention point (32), while keeping the floating platform (10) in place; and carrying out an intervention at the second intervention point (32).

Abstract: The invention is a device for eliminating the “tripping” of the BOP stack to the surface when switching between drilling and completion modes of operation on a drilling rig. This device is a new apparatus for attaching a BOP guide funnel, which will allow the funnel to be released and/or reattached while the BOP remains subsea on or near the seafloor. The new BOP guide funnel assembly consists of three basic components: a guide funnel, a connector shroud and a parking pile adapter. The guide funnel has a downwardly opening funnel on bottom (used to capture a wellhead) and an upwardly opening smaller funnel on top (used to guide the shroud back into the guide funnel during re-installation of the guide funnel). The connector shroud is permanently attached to the bottom of the BOP stack, surrounding the BOP wellhead connector and holds the guide funnel in place.

Abstract: The pad eye hole for the pin of a lifting bail, or clevis, has two different radii producing hole profiles that overlap to provide one larger hole. One radius is the same as the radius of the pin and arranged to wrap almost half of the pin circumference when it is thrust against the hole wall for lifting. An alternate form of the pin hole is egg shaped with the smaller radius equal to that of the pin but wrapping somewhat less of the pin circumference. The resulting hole will accept a somewhat misaligned pin but win closely engage the pin load bearing surface while lifting loads.

Abstract: A connection for oilfield use is disclosed. It features male and female components held together by dogs actuable through one of the members and into the other. Different configurations of the connections envision a built-in preload to the connection when made-up. This is accomplished by a cantilevered component at the extremity of one of the components of the connection. Alternatively, the preload feature can be incorporated into the dog or other locking assembly that holds the components of the connection together. The connection is particularly useful in subsea chokes which have a removable insert which can be mounted to or removed from the choke body which is located subsea.

Abstract: A slimbore marine riser and BOP are provided for a subsea completion system which includes a tubing spool secured to a wellhead at the sea floor. The tubing spool has an internal landing profile for a reduced diameter tubing hanger which is arranged and dimensioned to pass through the bore of the riser and BOP at the end of a landing string. The tubing hanger, arranged and designed to be sealingly positioned in the tubing spool landing profile, has a production bore and a relatively large multiplicity of electric and hydraulic passages which terminate at a top end of the hanger with vertically extending electric and hydraulic couplers. A passage is provided through the body of the tubing spool which provides communication from above the tubing hanger to the well annulus below the hanger. A remotely controllable valve is placed in the annulus bypass passage.

Abstract: An apparatus and a method for extending subsea hydrocarbon flowlines from an initial installation on a template/manifold system to later drilled subsea wells. The extension utilizes a pigging valve assembly which completes a flow path to allow for line cleaning or pigging and is modified by adding a curved flowline connector adaptor to extend the subsea flowlines. The apparatus and method minimizes the amount of equipment that must be pre-installed to provide such flexibility, thus facilitating the ability to defer incremental development decisions.

Abstract: A method and apparatus for temporarily storing the lower portion of a string of drill pipe in a well which has a cased portion wherein a packer, installed between a storm valve located below the packer and an actuator located above the packer, is set in the annulus between the drill pipe and the well casing, the actuator being designed to close the valve upon initial axial movement of the upper portion of the drill pipe, and then to become disengaged from the lower portion of the set drill pipe allowing the remaining surface suspended drill pipe and actuator to be retrieved as in the case of a floating drill ship or set aside for reconnection and reopening of the storm valve after a storm has passed.

Abstract: A bore selection apparatus (38) is described for facilitating access from a single bore riser to a production bore (34,34a) or annulus bore (36, 36a) without using a wireline-run whipstock. The bore selector apparatus disposed within the bore of a BOP stack (12) and which can be coupled between casing or tubing and a sub-sea test tree. The bore selector apparatus (38) can be actuated from the surface or from an ROV to provide a coupling between the tubing bore (44) and the production bore (34, 34a) or between the tubing bore (44) and the smaller annulus bore (36, 36a).

Abstract: A tree running tool is provided which has a means for actuating a latch for latching a side valve tree to a wellhead. Also disclosed is a tree running tool having an external axially movable actuator, preferably in the form of a sliding piston sleeve which is capable of exerting great forces. Also disclosed is a tree running tool having an external connector unit for connecting the tree running tool to a side valve tree. The connector unit is preferably mounted to the sliding piston sleeve and is for axially mechanically connecting the tree running tool to a linkage extending upwardly from the side valve tree.

Abstract: A quick connect/disconnect system for an offshore oil/gas production platform is facilitated by a submerged connection header for the platform. The platform comprises a vessel with a connection bay on vessel bottom. The vessel has the ability to be ballasted to position the connection bay either for connection or for transport toward and away from the connection header. The connection header houses the production lines and control lines and is positively buoyed and held in place by tension cables extending from the header bottom to the ocean floor. The quick connect/disconnect system comprises couplers for the production lines and control lines and devices for releasably linking the header to the vessel bay whereby the vessel may be held in a state of positive buoyancy by appropriately deballasting the vessel.

Abstract: A method and a device for replacing a seal element in an undersea blowout preventer is provided. A complete system includes a control center on the surface, an umbilical from the control center to a remotely operated vehicle (ROV), and a seal element carrier manipulated by the ROV. The carrier includes either a retrieving tool or a running tool, which retains a cartridge which is to be inserted into or has been retrieved from a BOP. The cartridge is split along a vertical plane, with each half of the cartridge becoming a temporarily integral part of a pipe ram on either side of the BOP. Alignment ramps on the cartridge mate with complementary surfaces on the respective faces of the pipe rams. The retrieving tool preferably includes means for hydraulically actuating the retrieving tool with pressure through the umbilical, such as coiled tubing.

Abstract: A subsea wellhead assembly comprises a subsea wellhead, a spool body assembly, a helix, and a tubular bore protector. The spool body assembly is mounted to the wellhead and has an inside surface defining a vertical bore. The spool body assembly has an upper end, a lower end, and a lateral production fluid outlet port. The helix is formed from a tubular member and is positioned in a lower portion of the spool body assembly. The helix has a generally cylindrical outer surface defining an outer diameter and a generally cylindrical inner surface defining an inner diameter, an upper end and a lower end. The tubular member has an organ pipe-shaped cut in the upper end so that the upper end is generally elliptically shaped and forms a pair of arcuate ramps to orient a tubing hanger. The tubular bore protector body has an upper end, a lower end, and a longitudinal axis.

Abstract: A fill-up valve is provided for a riser having a longitudinal axis that is connected at one end to a subsea wellhead and at the other end to a platform of an offshore oil or gas well. The fill-up valve is formed from a gate valve that mounts to an exterior of the riser and occupies a position extending less than the entire transverse periphery of the riser. The gate valve has a transverse profile projecting outward from the exterior of the riser that allows passage of the riser and fill-up valve through confined areas, such as through a rotary table of the well. A flow passage of the gate valve communicates with the interior of the riser to allow water to flow into the interior of the riser.

Abstract: An offshore fluid transfer system (10) is provided, of the type that includes a riser (32) having an upper end (34) connected through a universal joint (36) to a turret (22) on a vessel and having a lower end (36) anchored by catenary chains (40), and that also includes hoses (70, 71) extending from a base (50, 58) on the seafloor to the turret on the vessel, which avoids the need for a complicated hose structure to pass fluid across the universal joint. A fluid coupling (73) near the bottom of the turret, which is widely spaced from the universal joint, connects to a hose that extends from the fluid coupling in a sinuous path down to the seafloor base. The long length of hose, enables it to bend when the vessel drifts, to avoid excessive hose tension or riser contact during such vessel drift. A riser connector (102) can be operated to disconnect the riser from the turret so the riser can sink. The fluid coupling can include a fluid connector (100) which can separately disconnect the hose from the turret.

Abstract: An improved subsea template system. A drilling template is adapted to rest on the seafloor. The drilling template includes at least one conductor guide through which a well is drilled. An alignment structure is attached to the top of the conductor guide and fits within a conductor guide of a production template. The production template includes at least one conductor guide more than the drilling template. Once engaged, the alignment sleeve serves to coaxially align the conductor guide of the drilling template with a corresponding conductor guide of the production template.

Abstract: A two-part connector for use in connecting and disconnecting fluid carrying conduits includes male and female connector parts each having sets of non-radially disposed fluid carrying bores therethrough. A rotatable valve member extends across each set of bores therethrough and is adapted to align with the bores in the connector part in which the valve member is mounted. Each of the bores in the male connector part is aligned with a respective bore in the female connector part when the two connector parts are assembled together. Each valve member is rotatable to a first position in which the holes therein are aligned with the bores in the connector parts to permit fluid flow and to a second position in which the body of the valve member obturates the bores so that no fluid flows therethrough. Releasable clamping means retain the two connector parts together in sealing engagement.

Abstract: The bore selector includes a housing with an upper end having at least a first bore and a lower end with at least second and third bores. The housing includes a central bore extending between the upper and lower ends. A tube has its upper end connected to the first bore and its lower end adjacent the second and third bores. A yoke having an aperture therethrough for passing the tube, is reciprocably mounted within the bore of the housing. The yoke includes cam slots receiving guide lugs projecting from the sides of the tube. A hydraulic actuating means is also mounted in the lower end of the housing for reciprocating the yoke whereby as the yoke is reciprocated within the housing, the guide lugs move within the cam slots to shift the lower end of the tube between the second and third bores. A cage is mounted within the lower end of the housing to ensure alignment and sealing engagement between the lower end of the tube and the face of the housing around the second and third bores.

Abstract: A diverless and guidelineless method to connect two subsea flowlines by a jumper assembly is provided. Pivotable stabs and fluid connection means are provided on each end of the jumper assembly. The stabs mate into receptacles located on the subsea flowline connections. The flowline is preferably lowered vertically and hinged over while sequentially landing the two pivotable stabs into their respective stab receptacles.

Abstract: A method of drilling a subsea well involves partial drilling of several wells within a cluster. A base such as a template will have a receptacle. A gimbal mounts to a latching mechanism which in turn releasably latches an outer wellhead housing. The latching mechanism has an upward facing guide funnel. After setting conductor pipe, the well is drilled to a selected depth, an inner wellhead housing and a first string of casing are lowered through the funnel. The running tool for the inner wellhead housing has a funnel retriever which latches to the funnel. After the casing has been cemented, upward movement of the running tool will pull the funnel, latching mechanism and gimbal to the surface.

Abstract: A satellite tree module (STM) (10) for controlling flow between a satellite flow and a subsea production system includes at the bottom of the STM a connector (12) of an internal-latch, hydraulically operated type. A lower structure (14) consists of a central ring and projecting arms terminating in guide funnels. An upper structure (18) supports a reentry pole (20) integrated to the STM assembly (10) via an orientation key, a reentry mandrel (22) and a cap (24) for protection of the external profile of the reentry mandrel (22) and its receptacles. A flow system is arranged above the lower structure (14) and inside the upper structure (18). The flow system consists of a set of pipes and valves through which production/injection, production testing and lift-gas fluids flow. A flow line terminal (26) and a control system responsible for the activation of the STM (10) components during the operational phase are amounted to one of the upper and lower structures.

Abstract: Apparatus having removable posts for guiding subsea well equipment. The apparatus includes a frame for permanent attachment to a well installation. The frame includes outwardly extending legs with each of the legs for receiving an upstanding retrievable guide post. Each leg includes a latching mechanism and a guide foot for receiving an upstanding guide post. The latching mechanism includes a retainer rotatable between a latching position, a latched position and an unlatched position. The latching mechanism preferably includes a handle connected to the retainer with the retainer being rotatably connected to the top of the frame. The retainer may include a beam for engaging a shoulder on the guide post when in the latched position. The handle is in a downward position when the retainer is in the unlatched position prior to the guide post being seated in the guide foot.

Abstract: A split wear bushing for a subsea well assembly provides a standoff for the drill pipe to avoid damage to the casing near where it secures to the casing hanger. The split wear bushing has an outer wear bushing that locks into the casing hanger. An inner wear bushing lands in the bore of the outer wear bushing. The inner wear bushing has an inner diameter that is smaller than the inner diameter of the casing to provide a standoff. The inner wear bushing is carried on a wear bushing sub. An engaging shoulder on the wear bushing sub contacts the inner wear bushing during each trip of the drill string to pull the inner wear bushing from the outer wear bushing. The inner wear bushing relocks to the outer wear bushing on the return trip. A retrieval lock enables the outer wear bushing to be retrieved along with the inner wear bushing for the final trip.

Abstract: A subsea system for oil or gas production and water injection operates without divers' assistance and with guide-cables and includes a template (50) equipped with ten drilling mouths (53) arranged in two rows of five. Each drill mouth (53) has a guidepipe (54). The upper extremity of the guide-pipe presents an external section for locking purposes. A guide-base (55) is provided with four posts (56) removable by a ROV. A central space is provided in the template for the setting of a manifold (60) through four posts (63) to guide the installation and devices which ensure the final positioning of the manifold (6) within established tolerances. Bases of export-line terminals (64) are located in one of the extremities of the template (50) Each base (64) is provided with two guide-posts removable by a ROV, in addition to reaction posts (66) which orient the lowering of the pulling and connection tools and transfer the stresses to the structure of the template. Receptacles (67) lock the export-line terminals.

Abstract: The invention relates to an apparatus for recovering a wellhead. The apparatus includes a housing, a latch, and a latch device actuator which are responsive to a force applied to the apparatus to separate the apparatus from the wellhead, which force will then cause the latch device to engage an external, rather than internal, profile of the wellhead so that the apparatus remains in engagement with the wellhead. The apparatus also includes a shaft which is capable of carrying a cutting mechanism to facilitate severing of the wellhead.

Abstract: A flowline selector device has a housing with a single passage at the upper end and two or more passages at the lower end. A tube connects to the upper end and has a lower end that is offset from the axis of the housing. Reciprocating the tube up and down and rotating it causes the tube to index between the various ports in the lower end of the housing. The lower end of the tube stabs into cylindrical bores in each port. A piston located at the upper end of the tube cooperates with an orientation sleeve to cause the indexing and reciprocating movement.

Abstract: An operational package comprising either a pump/driver package (1; 100) or a valve package (250) is retrievably installed at a subsea station by a receptacle (10; 110; 251). Co-operating connection means on the package and the receptacle establish fluid and/or electrical connection between the package and the receptacle on reception of the package within the receptacle. Seal means (14) carried by the package are moved into a condition to seal any such fluid connections. Installation is effected by establishing a running loop extending from a surface vessel downwardly through the receptacle (10; 110) and upwardly to the surface vessel outside the receptacle, the package (1; 100) being moved on and guided by the wire loop from the surface vessel into the receptacle.

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 hanger comprising two tubular sections, one partially received within the other, one section having a serrated surface and the other section retaining at least one detent whereby the axial length of the hanger is adjustable. This arrangement obviates the disadvantage in the conventional tie-back method of sub-sea wellhead completion wherein it is necessary to cut and dress the casing after pulling tension in the casing string.

Abstract: A fluid operated tool 30 (FIG. 4) for use in replacing a body clamped between facing platens has an open ended tubular member 31, through which the body can pass, that carries outwardly thereof, and axially extending, coplaner support arms 33, 34 at the end of which are hydraulic piston and cylinder arrangements 35, 36 for inserting between the platens to overcome the clamping force on the body, permitting it to be removed and replaced by way of the tubular member 31. The tool may be used subsea with a submersible to handle it and provide hydraulic power.

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: A subsea structure for oil well drilling, completion and production and specially designed for utilization in water depths of 1,000 m or more. The structure includes a template having radially extending structures and which extends radially from a central foundation, on top of which the template shall be set and where a central manifold for controlling the production of wells is located. Each structure arm is provided in its extremity with an opening for adaptation of a guide-base for well drilling, and one of the arms of the template (1) is intended to receive connectors (6) of export and well control lines.

Abstract: A subsea oil and/or gas production system comprises a template having a three-dimensional framework enclosing one or more production bays, each bay having a well slot and a manifold slot. The space above the well slot is occupied by a tree module fitted with a high pressure cap. The space above the manifold slot is occupied by a manifold header module positioned on the template and forming the base of the equipment in the area of the manifold slot(s), isolation valve module(s) positioned adjacent to the manifold header module and connected thereto, flow control modules(s) positioned adjacent to the isolation valve module(s) and connected thereto, production choke module(s) positioned adjacent to the flow control module(s) and connected thereto, and production control pod(s) positioned adjacent to the flow control modules(s) and connected thereto. The tree module(s) are connected to the flow control module(s).

Abstract: A guide base for a sub-sea well is formed in two parts, an annular portion fixed to a conductor housing and a retrievable portion surrounding and releasably attached to the annular portion. The retrievable portion can be recovered and used elsewhere if a well is suspended or abandoned or changed for another type of guide base after drilling and before completion. A trawler board deflector can also replace the retrievable guide base portion, and a retrievable protective cap may be placed on the well head housing of a suspended well. A hydraulically-operated multi-purpose tool may be used for placing or retrieving any of the retrievable items.

Abstract: Guide posts for any part of a sub-sea oil or gas installation can be installed in or removed from a guide foot solely by vertical movement. The guide post end has a surrounding locking sleeve capable of sliding axially relative to the guide post end and there is at least one locking mechanism formed of a ring or segments on the guide post and co-operating with at least one groove in the guide foot. Upward movement of the guide post end relative to the locking sleeve locks the mechanism, and upward movement of the locking sleeve relative to the guide post end unlocks it. The mechanism may be automatically reset by the unlocking action so that guide posts may be transferred underwater without being brought back to the surface, although damaged posts can always be retrieved if required. Tools for unlocking and removing the guide posts are also described, one of the tools being capable of dealing with bent guide posts.