Abstract: An undersea drilling template adapted to be lowered onto a seabed by a drillpipe. The template comprises a template base and at least one arm having a releasable clamping assembly for releasably connecting the template to the drillpipe. The clamping assembly is adapted to be clamped to the drillpipe during lowering of the template and release from the drillpipe when the lowering is completed.

Abstract: An apparatus for retaining fluid in a pipe includes an elongated body adapted to be positioned within a subsea wellhead assembly. The elongated body has an end adapted for connection to the pipe, a flow passage for fluid communication with the pipe, and an outer surface for engagement with a sealing member in the subsea wellhead assembly. A first chamber is defined within the elongated body and connected to receive pressure from above the subsea wellhead assembly. A second chamber is defined within the elongated body and connected to receive pressure from below the subsea wellhead assembly. A valve is supported in the elongated body for movement in response to pressure differential between the first and the second chambers. The valve is movable between an open position to permit fluid flow through the flow passage and a closed position to prevent fluid flow through the flow passage.

Abstract: An internal tieback connector for connecting a riser from a platform to a subsea wellhead having internal grooves and a casing hanger therein. The connector has an inner body which carries a lower housing adapted to land on the wellhead. A plurality of dogs abut the lower housing and are adapted to engage and lift the inner body relative to the lower housing. An upper housing is carried on the inner body and adapted to force the dogs inward into engagement with the inner body. A plurality of latch members are carried on the inner body and are adapted to engage the internal grooves when the internal is moved upward relative to the lower housing.

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 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 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 method and apparatus for removing abandoned or obsolete fixed platforms in a marine environment is provided. The apparatus includes a frame carrying an explosive charge. The frame includes a linear and a curved section which are adjustable moved relative to one another for fitting the explosive charge member to the inside bore of a vertical leg section of the rig. A shaped charge arrangement focuses an explosive charge at a desired location on the rig leg so that when the explosive charge detonates, the rig is cut with minimal invasion of the surrounding environment.

Abstract: A connector device for connecting a wellhead christmas tree assembly to a wellhead wherein the device comprises a cylindrical body adapted to be placed in sleeved relationship to the wellhead and having means for attaching a wellhead christmas tree assembly in coaxial relation therewith. The cylindrical body member is further provided with a plurality of lateral openings in equiangular relationship with respect to the axis of the body member. The connector further includes a plurality of locking dogs, each having a toothed front face in conforming configuration with the wellhead exterior and each disposed in a different one of the lateral openings. The connector also includes a first drive means comprising a locking sleeve with an internal camming surface for interacting with a matching cam surface on the back face of each of the locking dogs and adapted by an actuator to drive the locking dogs into locking engagement with the wellhead.

Abstract: A caisson wellhead system having a weak point wherein the wellhead system may be installed in a well as a single unit. The caisson wellhead system of the invention includes a lower tubular member having an upper rim. A lower rim of an upper tubular member is placed on the upper end of the lower tubular member. A removable connector is installed inside of and between the lower tubular member and upper tubular member for temporarily connecting the upper tubular member and the lower tubular member. A weak point is formed at the interface between the lower tubular member and the upper tubular member when the removable connector is removed. Therefore, the caisson wellhead system will break at a controlled location if any external components of the well equipment are struck by a foreign object such as an iceberg.

Abstract: A spanner joint assembly for connecting between an upper riser and a conventional dual bore tubing hanger in a subsea well. The spanner joint assembly includes upper and lower spanner joint portions connected to each other through an emergency disconnect portion. The upper spanner joint portion has a longitudinal production bore and a longitudinal annulus. The lower spanner joint portion has a longitudinal production bore with a production bore valve and a longitudinal nonconcentric annulus access bore. The emergency disconnect portion includes an upper mandrel connected to the upper spanner joint portion and a lower mandrel connected to the lower spanner joint portion. A releasable mechanical connector includes a retaining groove in the lower mandrel and a collet connected to the upper mandrel. The collet has a latching portion extending beyond the upper mandrel which is adapted to be received in the retaining groove.

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: In accordance with certain preferred aspects of the present invention, there is provided tree running tool with a mechanical mechanism for unlatching the tree running tool from a side valve tree. The tree running tool is formed from a tool body, a stem, a telescoping element, a retractable spacer, a means for moving the spacer, and a means for attaching the telescoping element to a lift device. The tool body has an upper end, a lower end, and a longitudinal axis. The stem is fixedly attached to the upper end of the tool body and extends axially therefrom. The stem has a lower end attached to the tool body and a generally annular flange at a position spaced apart from the tool body. The telescoping element is positioned alongside the stem. The telescoping element has a generally annular flange at a position between the generally annular flange of the stem and the tool body.

Abstract: A blowout preventer control system has been developed with a pod with features which include a retractable internal stab with fixed internal hydraulic connection lines to the blowout preventer. The hydraulic connection lines are connected by pressure activated packer seals. The stab also has an electrical connector to the blowout preventer which uses a guide which proper aligns the pins of the connector without any rotation. The piping of the control system uses an adjustable length type tubing to reduce the binding on the pipe. A lost motion float is used reduce the loading on the connection bolts of the system. The entire system is enclosed with plates with keep the expended hydraulic fluid in contact with the internal mechanisms. The transducers and seal subs are located for easy accessibility with no disruption of the surrounding elements of the system.

Abstract: An emergency recovery system designed for use in a subsea environment is disclosed. The emergency recovery system has a casing that is open at each end with a shackle connected to one end of the casing with the opposite end of the shackle designed for connection to appropriate points on the main stack and lower marine riser package in any orientation. A flexible sling with a closed loop formed at each end is used with one of the closed loops releasably connected to the shackle and the end of the casing. The other end of the sling has a flotation member attached to the sling adjacent the closed loop. The sling is fan folded as it is lowered into the casing. The flotation member is shaped to fit inside the other end of the casing with the closed end loop of the sling protruding from the casing. A split retaining ring is placed around the sling between the flotation member and the closed loop and inserted in the open end of the casing.

Abstract: A system for transporting hydrocarbon fluid produced from an offshore well using an offshore production platform and a hydrocarbon fluid storage space in fluid communication with the offshore well via a conduit is provided. The system comprises at least one hydrocarbon fluid export system including a shuttle tanker provided with positioning apparatus capable of limiting movement of the tanker away from a location at a selected distance from the production platform, a flowline for transferring the hydrocarbon fluid to the tanker, at least pan of the flowline being a continuous flexible flowline at one end provided with a connector for releasably connecting the flowline to the tanker so as to allow fluid transfer from the flowline to the tanker, and with a valve for opening or closing the flowline, the flexible flowline extending along the seabed and from the seabed in the form of a riser to the tanker when the flowline is connected to the tanker.

Abstract: A single drilling guide base for subsea oil wells includes two parts, namely a lower part (1) and an upper part (2), which are bolted together (at 7). The whole arrangement is provided with a seating indicator (5) connected to the lower part and holes in a funnel shaped portion of the upper part for the discharge of gravel.

Abstract: A system for turning a swivel aboard a vessel for oil extraction at sea includes a stationary swivel part connected to a rotary drilling rig on the vessel and one or more rotating parts connected to the vessel. The rotating swivel parts are connected to a torsionally rigid vertical frame structure via a drive mechanism which transmits rotary motion between the vessel and the swivel without angular displacement or significant reactive forces in the frame structure. The vertical frame structure includes four walls where one of the walls forms a gate for the insertion and removal of an entire swivel or parts of a swivel. The frame structure is attached to an overhead frame that extends across the diameter of the rotary drilling rig and is secured to the hull of the vessel.

Abstract: A cased suspended sub-sea well is secured for abandonment by setting a packer in the casing thereof, the packer having a perforating gun suspended therefrom firing the gun to perforate the casing and then injecting cement into the annulus behind the casing.

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 submarine wellhead (10) for producing wells, including a hollow body (14) mounted in a water-tight fashion on a well (16) configured to receive a suspension device (30) equipped with a production column (26) designed to be lowered down into the well, which body (14) is also equipped with an outlet port (20) for the oil coming up from the well through the production column (26), hydraulic flow between the production column (26) and the outlet port (20) occurring through the suspension device (30), and hydraulic flow being ensured regardless of the rotation position of the suspension device (30) in relation to the body (14).

Abstract: Environmentally-safe work-over operations are carried out on a well of an offshore platform by transporting an auxiliary oil-and-water separator together with well work-over equipment and installing it temporarily on the platform. The large volumes of oil- or chemical-contaminated fluids generated during a well work-over operation are collected and run through the high-capacity auxiliary oil-and-water separator before being disposed of and without upsetting the performance of the regular platform separator handling the flow of production fluids from other wells on the platform.

Abstract: An anchor system for temporarily anchoring the lower end of a lower marine riser package (LMRP) assembly, drilling riser, and drill string used in drilling subsea wells. The anchor system includes a dummy wellhead secured to the ocean floor and weight means stored in a dummy wellhead that can be connected to the end of the drill string in a manner that restrains the lateral movement of the LMRP assembly, drilling riser, and drill string.

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: A choke arrangement useful in subsea completions in a subsea tree cap. The subsea choke arrangement allows for refitting of existing subsea tree arrangements to allow for the installation of a choke arrangement that can be easily maintained and removed. Also, a choke arrangement is shown that allows the choke to be isolated after failure which permits continued production of the well until repair or replacement operations can be implemented.

Abstract: Apparatus is disclosed for use in drilling an offshore well wherein a drill string suspended from a drill ship for extension within a riser pipe, lower marine riser package and subsea wellhead including a blowout preventer stack may be sheared at a location intermediate the lower end of the riser pipe and a flex or ball joint of the riser package.

Abstract: A torque tool and mating profile allow large diameter conductor pipe to easily be retrieved from a subsea well. The profile will be located near the sea floor immediately above a left-hand threaded connector joint. The profile has a lifting shoulder and a torque key. The torque tool lowers through the conductor pipe from the drill rig on drill pipe. It has spring biased dogs that spring outward into the profile. The dogs have lifting surfaces for lifting the conductor string at the lifting shoulder at the profile. Rotating the torque tool causes it to engage the torque key to break out the connector joint.

Abstract: A device for retaining tubular inner and outer members together in a well allows the members to be pulled apart with a sufficient shear out force. The members have mating retaining and reaction groooves. The retaining groove has a deeper portion joining a shallower portion which is bounded by a shearing side wall. The reaction groove has a shearing side wall which opposes the shearing side wall of the retaining groove when the inner and outer members are fully inserted together. A solid elastomeric ring is carried within the retaining groove. The ring locates in the deeper portion when the inner and outer members are being pushed together. When a pulling apart force is applied, the shallower portion slides relative to the ring until the ring locates in the shallower portion and is contacted by the opposed shearing side walls.

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 subsea drilling drive pipe apparatus for drilling offshore wells from a floating vessel into the ocean floor. An elongated drilling drive pipe including a plurality of locking pads which are circumferentially positioned about the drive pipe periphery. A foundation structure is removably engageable with the elongated drive pipe by one or more locking pins which detachably engage the drive pipe thereby permitting the assembled members to be lowered as a unit to the ocean floor in contemplation of a subsea well drilling operation.

Abstract: Disclosed is a method for disconnecting a marine riser assembly from a subsea wellhead when the marine riser assembly contains substantially gas, the marine riser assembly comprising a riser and a wellhead connector having an internal shoulder for abutting against the top of the subsea wellhead. The method comprises equalizing the pressure acting on the internal shoulder of the wellhead connector and the seawater pressure acting external to the wellhead connector.

Abstract: Control apparatus for a sub-sea wellhead installation, for example of a satellite well, is disclosed which includes a plurality of control devices 80 each for providing a control function for the installation 10 and a connector 40, 45, 50 for connecting the devices 80 to the installation 10, each control device being independently engageable and disengageable with the connector 40, 45, 50. The connector includes a manifold 40 to which are connected a plurality of receptacles 50, each control device 80 being engageable with the the receptacle 50. The receptacles and control devices are preferably provided with complementary engageable portions 52, 54, 56; 82, 84, 86, which include hydraulic and electrical connectors 58, 60, 62, 70, 72; 88, 90, 92, 98, 100, so that control signals may be passed via the connectors 40, 45, 50 to the control devices 80 from a command installation and actuation signals may be passed from the control devices 80 through the connector 40, 45, 50 to devices on the installation 10.

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 subsea well choke system is disclosed. The well choke system has annulus and tubing access as well as wing lines for connections to flow lines. A pressure control valve is installed in the tree cap for easy replacement and also to facilitate pigging and well test operations.

Abstract: A drill ahead tool for drilling the initial portion of a subsea well allows an operator to drill ahead after running conductor pipe. The running tool locates in the wellhead housing secured to the upper end of the string of conductor pipe. The running tool has a mandrel that connects into the string of drill pipe. The mandrel locates in a sleeve. The sleeve locates in a body of the running tool. The body has dogs which engage a groove in the wellhead housing to secure the running tool to the wellhead housing while the conductor pipe is being run. The sleeve has a cam on its exterior for maintaining the dogs in the extended position. The drill pipe rotates the sleeve to advance the cam to allow the dogs to be retracted. The mandrel and sleeve have a J-slot and pin that allow the mandrel to be released from the sleeve to continue drilling ahead.

Abstract: The present invention relates to a method for replacing an insert unit included in an insert valve assembly belonging to a subsea production system for gas and oil. In carrying out the method, a manipulator (1) is brought by means of a sheave (2), a hoisting cable (3) and guide wires (4, 5) down to a predetermined location on the bottom of the sea. The manipulator comprises a telescopic arm (15, 16) which is then moved towards and fixed by means of a hook (20) and a lug (21) to a valve tree (17) which supports a valve (22), the insert unit (26) of which is to be unscrewed from the respective valve housing and be replaced. A carriage (18) located in the manipulator and comprising retracting, aligning and fixing devices (32, 33, 34) is brought with the aid of the telescopic arm and a rail, located on the top side of the carriage, towards the valve tree and is fixed to retraction cones (35, 36, 37) mounted on the valve tree.

Abstract: An upper marine riser package (10/10A) comprising a diverter (D) for diverting uncontrolled gas and return drilling mud therethrough, a flexible joint FJ for allowing tilting motion between a vessel and a riser string (RS), a self-tensioning slip joint (SJ) and riser rotation bearing joint (RB) suspended below said vessel (V) to compensate for vertical motion between a subsea well (W) and a floating vessel (V). The upper marine riser package (10/10A) is sized to be run through a confined opening such as a riser handling spider (HS) and rotary table (RT) and to be suspended and operated below the deck of the vessel (V). The upper marine riser package can be used to eliminate the conventional riser tensioners normally above the platform and can be used in combination with such conventional riser tensioners normally above the platform for deeper and deeper drilling opertion.

Abstract: A method and apparatus for abandoning an offshore oil or gas well drilled into the ocean floor having a plurality of concentric strings of pipe having throughbores and spaced to form an annular space between adjacent pipe strings. The invention includes perforating the pipe string with an explosive charge of a size, composition, and velocity so as to only penetrate one pipe string without damaging or penetrating any other pipe string in the well.

Abstract: A subsea drilling and production system where the production unit is removably connected onto a drilling template and operatively connected to one or more Christmas trees so that the production unit may be disconnected from the trees and removed from the template without first removing any of the trees and so that any of the trees may be disconnected from the production unit and removed from the underwater site without removing the production unit.

Abstract: A system for connecting an exploratory well into a producing well by retrieving a permanent guide base (P) and replacing the same with a completion guide base (C) containing the necessary equipment for producing from the well. To do this, the permanent guide base comprises two parts; a gimbal part (32) and a platform part (34)--the platform part (34) can be detached from the low pressure wellhead housing (W) and retrieved leaving the wellhead housing (W) and the permanent guide base gimbal part (32) subsea. The wellhead housing (W), provided with a latching profile (154), though not used during exploratory drilling, is now used to latch the completion guide base (C) thereto for production from the well. The two parts of the retrievable permanent guide base are latched together by a latching mechanism (74) which is easily releasable to unlatch one part from the other, and both guide bases (P & C) are provided with wire line guide posts (82) which are easily detachable for replacement if necessary.

Abstract: A remotely releasable pipe connector is described and comprises a first tubular connector or "pin connector" having at least one laterally extending locking member, and a slotted second tubular connector or "box connector" cooperatively disposable over the first tubular connector with the slots thereof removably engaging the first tubulars connector's locking members. One or more shear plates are attachable to the second tubular connector and are positioned to prevent the release of the locking members from the slots in the second tubular connector until the shear plates are subjected to a force greater than or equal to a predetermined force.

Abstract: A method of cutting and retrieving submarine well casing which includes the steps of lowering a tool on a string into the bore of the well casing which tool includes a casing cutter, a bumper sub connecting from the cutter to the combined anchor swivel and latching means to retain the anchor in unset position when it is being run with the string connected to the upper end of the tool, landing the tool with the swivel supported on the upper end of the casing and the remainder of the tool within the casing, releasing the latching means, raising the string to set the anchor, tensioning the string, energizing the cutter arms, rotating the string to cut the casing, and raising the string to retrieve the cut casing. The apparatus includes a casing cutter, a bumper sub, a combined anchor swivel and latching means to retain the anchor in unset position which latching means is actuated to unlatched position by manipulation of the string on which the tool is supported.

Abstract: An apparatus for lifting a blow-out preventer during oil or gas drilling operations includes a base frame which can be manually positioned atop the rotary table of the drilling platform of the drilling rig used to drill the well. The apparatus further includes a pair of winches which can be lowered to preselected positions on the base frame, after positioning the base frame on the rotary table, and secured to the base frame via pins that extend through clevises that are welded to the base frame and through apertured lugs that are welded to the winches and extend into the clevises. The blow-out preventer is lifted by the winches via cables that are wrapped on reels of the winches and passed through the base frame and rotary table to the blow-out preventer to which the cables are attached.

Abstract: A termination means for a plurality of riser pipes at a floating platform including a termination member for supporting said plurality of riser pipes, said termination member being supported and suspended by constant tension means on said platform. The plurality of riser pipes include a central riser pipe and satellite riser pipes arranged around said central riser pipe. Each of the satellite riser pipes extend through the termination member and are supported from said termination member by fluid pressure actuated tension compensator means which serve to tension each of the riser pipes. The termination means is adapted to both rigid and flexible riser pipes.