US Pat. No. 9,163,751

FLOATABLE SPOOLBASE WITH INTERMEDIATE CAROUSEL STORAGE

Subsea 7 Limited, Sutton...

22. A method of storing rigid pipe at a water-based spoolbase for supply to a reel-lay pipelaying vessel that visits the water-based
spoolbase,the water-based spoolbase having a unitary rigid buoyant body supporting a storage reel and a welding station upstream
of the storage reel, the method comprising welding pipe elements to a pipe and winding the pipe onto the storage reel, which
storage reel has an upright rotational axis.

US Pat. No. 9,074,706

PIPELAYING

Subsea 7 Limited, Sutton...

1. A piggybacking clamp for subsea laying of two or more elongate elements in a piggybacked arrangement, the clamp comprising:
a plurality of clamp segments assembled to surround and clamp the elongate elements, each clamp segment having two or more
generally parallel mutually spaced recesses shaped to extend partially around respective ones of the elongate elements; and

retainers that hold the clamp segments together when assembled, such that the assembled clamp segments apply clamping forces
to the elongate elements in the recesses;

wherein the retainers are male fixings on one of the plurality of clamp segments, which male fixings are received in complementary
holes in another of the plurality of clamp segments with an interference fit that maintains the clamping forces by friction
between the male fixings and internal surfaces of the holes.

US Pat. No. 9,140,384

SUBSEA CONNECTING APPARATUS AND METHOD

Subsea 7 Limited, Sutton...

1. A method for attaching a pipeline termination assembly having a pivot axis member defining a pivot axis for the pipeline
termination assembly to a subsea structure having one or more capture slots to receive the pivot axis member, comprising:
capturing the pivot axis member in the one or more capture slots, the one or more capture slots allowing vertical movement
of the pivot axis member of the pipeline termination assembly; and

rotating the pipeline termination assembly about the pivot axis defined by the captured pivot axis member engaged in the one
or more capture slots to assume a horizontal position, the one or more capture slots then permitting horizontal movement of
the pivot axis member of the pipeline termination assembly back and forth along the capture slot as the pipeline expands or
contracts;

wherein a capture device mounted on the subsea structure provides said one or more capture slots,
the method further comprising moving at least a first part of the capture device with respect to the subsea structure to retain
the pivot axis member in the one or more capture slots on rotating the pipeline termination assembly about the pivot axis.

US Pat. No. 9,422,773

RELATING TO BUOYANCY-SUPPORTED RISERS

Subsea 7 Limited, Sutton...

1. A subsea riser support buoy comprising:
a positively buoyant riser support member and a positively buoyant jumper support member that extend generally parallel to
each other and that define a lengthwise direction extending between them across the buoy, the riser support member and the
jumper support member being spaced apart from each other in the lengthwise direction;

side members that extend in the lengthwise direction at ends of the riser support member and the jumper support member to
join the riser support member and the jumper support member; and

pontoons of negative or neutral buoyancy that extend lengthwise from opposed ends of each side member and beyond the positive
buoyancy of the riser support member and the jumper support member, the pontoons comprising attachment points for connecting
tethers to the buoy.

US Pat. No. 9,227,700

TENSIONING AND CONNECTOR SYSTEMS FOR TETHERS

Subsea 7 Limited, Sutton...

1. A top connector for a tether of a tethered buoyant structure, the top connector comprising:
a support comprising an annular collar that surrounds and defines a seat for a resilient annular bush;
a frame extending upwardly above the support when oriented for use, the frame carrying chain-management features for supporting
a portion of a chain of the tether in use; and

a lever member comprising a down tube extending below the support when oriented for use, the down tube being pivotably connected
to the support via a flex joint; and

the flex joint comprising the resilient annular bush connected to the down tube;
wherein the down tube is pivotable relative to the support and the frame.

US Pat. No. 9,052,040

ALIGNMENT TOOL FOR ALIGNING SUBSEA ELEMENTS IN A PIGGYBACKED ARRANGEMENT

Subsea 7 Limited, Sutton...

14. A method of aligning a secondary elongate element with a primary elongate element for subsea laying of the elements in
a side-by-side piggybacked arrangement, comprising feeding the secondary element at a first angular position with respect
to the primary element along a space between neighbouring tracks of a tensioner and then guiding the secondary element into
a second angular position with respect to the primary element for attachment to the primary element.

US Pat. No. 9,234,400

SUBSEA PUMP SYSTEM

Subsea 7 Limited, Sutton...

1. A subsea pump system adapted to close a hydraulic ram of a blowout preventer, the subsea pump system comprising a plurality
of pumps including at least a first pump and a second pump configured to pump a driven fluid from a driven fluid source to
the hydraulic ram, each of the first and second pumps having a drive side configured to drive the pump, each drive side being
fed drive fluid from a drive-fluid source, and a driven fluid side, each driven fluid side being configured to feed driven
fluid to the same hydraulic ram, and wherein the subsea pump system has a controller adapted to select at least one of the
first and second pumps for pumping the driven fluid to the hydraulic ram by selectively feeding fluid from the drive fluid
source to the drive side of the at least one of the first and second pumps, wherein the first pump is adapted to pump driven
fluid at higher flow rates than the second pump, and wherein the second pump is adapted to pump driven fluid at higher pressures
than the first pump, whereby the controller is configured to feed drive fluid to at least the drive side of the first pump
to activate the first pump hydraulically at a lower fluid pressure range and the controller is adapted to feed drive fluid
to at least the drive side of the second pump to activate the second pump hydraulically at a higher fluid pressure range.

US Pat. No. 9,162,734

METHOD OF INSTALLING A BUOY AND APPARATUS FOR TENSIONING A BUOY TO AN ANCHORING LOCATION

Subsea 7 Limited, Sutton...

1. A method of installing a production buoy to subsea anchoring foundations, the method comprising, in order, the steps of:
floating a production buoy over the subsea anchoring foundations;
hanging at least one tether off the production buoy such that the or each tether extends from the production buoy towards
the subsea anchoring foundations;

submerging the production buoy to a connection depth which allows connection of the or each tether to the subsea anchoring
foundations; and

connecting the or each tether to the subsea anchoring foundation beneath the buoy.

US Pat. No. 9,121,230

RESTRAINT SYSTEMS FOR HYBRID DECOUPLED RISERS

Subsea 7 Limited, Sutton...

1. A seabed-to-surface riser system comprising:
a group of two or more subsea riser supports each extending upwardly from a seabed anchorage to a buoyant upper end region
located beneath the surface and each supporting at least one riser pipe extending from the seabed to the upper end region;
and

at least one jumper pipe extending from the upper end region of each riser support to a surface installation at a location
above the riser support, the riser supports and the surface installation defining a flow direction of well fluids that, when
the system is viewed from above, extends generally from the upper end regions of the riser supports toward the surface installation,
and the surface installation being spaced horizontally from the riser supports in the flow direction;
wherein:
the group of riser supports is disposed to one side of the surface installation;
at least outermost riser supports of the group lie on an axis transverse to the flow direction;
a plurality of laterally-extending flexible lines are attached to each of the outermost riser supports, the plurality of laterally-extending
flexible lines each applies mutually-opposed stabilising forces to each of the riser supports in the group of riser supports
in directions transverse to the flow direction; and

at least one of the laterally-extending flexible lines is a mooring line that extends from an outermost riser support of the
group to the seabed,

wherein a riser support of the group is connected to one or more neighbouring riser supports of the group by at least one
of the laterally-extending flexible lines extending transversely with respect to the flow direction.

US Pat. No. 9,488,304

TECHNIQUES FOR JOINING LINED PIPELINES

Subsea 7 Limited, London...

1. A pipeline joint arrangement between lined subsea pipes abutting end-to-end as used in the subsea oil and gas industry,
wherein the joint arrangement comprises:
a connector bridging spaced-apart liners of the pipes, the connector having:
a tube having opposed ends, the tube defining opposed male interface elements extending inwardly from respective ends of the
tube; and

at least one circumferential permeable choke projecting radially from each male interface element to control fluid flow around
the tube in use;

and each liner comprises:
a body section;
an end section of lesser thickness and greater bore than the body section; and
an inner step disposed between the body section and the end section;
and wherein:
a respective male interface element of the connector is received telescopically by the end section of each liner, with mutual
clearance defining an annular channel between the male interface element of the connector and the end section of the liner;

a respective end of the tube opposes the inner step of each liner; and
at least one permeable choke extends radially from each male interface element to the opposed end section of each liner to
restrict but not prevent fluid flow in the respective annular channels in use of the pipeline, the choke being designed to
collapse away from the liner over a threshold differential pressure applied across the choke to permit high-volume flow through
the respective annular channels.

US Pat. No. 9,387,911

LAUNCH AND RECOVERY TECHNIQUES FOR SUBMERSIBLE VEHICLES AND OTHER PAYLOADS

Subsea 7 Limited, Sutton...

12. A system for recovering a payload from an seabed location, the system comprising:
a lift line;
a thruster-equipped latch unit attached to the lift line and steerable in x- and y-axes horizontally through water to carry
the lift line toward a payload at an underwater location, the latch unit having a latch formation to attach the latch unit
to the payload, and being arranged to transmit lifting tension from the lift line to the payload via the latch formation to
recover the payload;

a heave-compensating winch which in use pays out the lift line to lower the latch unit toward the payload, controls a z-axis
position of the latch unit during lowering, and

increases the tension applied through the lift line via the latch unit is progressively increased to detach the payload from
a seabed location.

US Pat. No. 9,664,307

IMPROVEMENTS RELATING TO ABANDONMENT AND RECOVERY OF PIPELINES

Subsea 7 Limited, Sutton...

1. A method of abandoning a pipeline during subsea pipelaying from a pipelay vessel, the method comprising:
coupling the top of a pipe string indirectly to a lower tendon element of an abandonment string;
suspending the pipe string from the lower tendon element;
releasably engaging further tendon elements in succession to an upper end of the abandonment string while lowering the pipe
string into the sea, such that the pipe string and the abandonment string are in end-to-end alignment under tension along
a launch axis under the weight load of the pipe string;

lowering the top of the pipe string to a handover depth;
at the handover depth, applying tensile force via a wire from the vessel to the top of the pipe string, the wire being at
an acute angle to the launch axis;

by application of tensile force via the wire, deflecting the pipe string from the launch axis toward end-to-end axial alignment
with the wire to transfer the weight load of the pipe string to the wire; and

decoupling the abandonment string from the pipe string.

US Pat. No. 9,200,728

PIPELAYING

Subsea 7 Limited, Sutton...

1. An apparatus for clamping elongate elements in a parallel piggybacked arrangement during subsea laying of the elements,
the apparatus comprising opposed reciprocating jaws that move orthogonally with respect to a launch direction of the elements
toward one another in an assembly stroke and retract in a return stroke, each jaw having a cavity shaped to accommodate a
clamp segment, and each jaw being arranged to force together the clamp segments around the elongate elements to assemble a
piggybacking clamp that applies clamping forces to the elongate elements, wherein the cavity of each jaw has at least two
press surfaces for applying assembly force to separate locations of a clamp segment in the cavity, those locations being disposed
to either side of a portion of the clamp segment that accommodates at least one of the elongate elements, and wherein the
jaws are supported by a carriage that is movable reciprocally in an engagement stroke in the launch direction during clamping
and in a return stroke opposed to the launch direction after clamping.

US Pat. No. 9,121,529

METHOD OF LAYING A HYBRID PIPELINE ON THE SEABED

Subsea 7 Limited, Sutton...

1. A method of laying a hybrid pipeline comprising a rigid pipe section that lies on the seabed and a flexible jumper which
is connected to the rigid pipe section, comprising the steps of:
(i) lowering a rigid pipe section onto the seabed,
(ii) raising one end of the rigid pipe section on the seabed to the surface of the sea, while leaving a portion of the rigid
pipe section on the seabed,

(iii) connecting one end of a flexible jumper to the raised end of the rigid pipe section so that the flexible jumper and
the rigid pipe section are in fluid communication, and

(iv) lowering the one end of the flexible jumper to the seabed with the raised one end of the rigid pipe section attached,
to return the raised one end of the rigid pipe section to the seabed and to lay the flexible jumper on the seabed,

wherein a connection between the raised one end of the rigid pipe section and the flexible jumper receives auxiliary support
from an abandonment and recovery winch and winch line on a flexible lay vessel used for deployment of the flexible jumper,
when the one end of the or each flexible jumper is lowered to the seabed with the respective raised one end of the rigid pipe
section attached, to return the raised one end of the rigid pipe section to the seabed and thereby maintaining a sufficient
bending radius in the flexible jumper greater than a minimum bend radius of the flexible jumper.

US Pat. No. 10,088,078

SUBSEA DRYING SYSTEM

Subsea 7 Limited, Sutton...

1. A subsea drying system for drying a chamber underwater, the system comprising:a source of pressurised drying fluid comprising a container of drying fluid located underwater and beside the chamber;
an upstream piping between the source and a chamber inlet interface for conveying drying fluid to the chamber in use;
downstream piping between a chamber outlet interface and an outlet for conveying to the outlet and expelling from the system through the outlet liquid displaced from the chamber by drying fluid entering the chamber in a dewatering mode;
a recirculation path between the downstream piping and the upstream piping for conveying drying fluid exiting the chamber from the downstream piping to the upstream piping in a dehumidifying mode;
a dehumidifier in the recirculation path; and
a valve system for selectively closing and opening the recirculation path, the valve system comprising a first isolating valve between the upstream piping and the recirculation path, a second isolating valve between the downstream piping and the recirculation path, and an outlet valve at the outlet;
the system being is operable in an open loop in the dewatering mode and in a closed loop in the dehumidifying mode;
in the open loop, the valve system closes the recirculation path by closing the first and second isolating valves, and opening the outlet valve, so as to isolate the upstream and downstream piping from the recirculation path and prevent fluid communication therebetween, thereby directing liquid displaced from the chamber through the outlet; and
in the closed loop, the valve system opens the recirculation path by opening the first and second isolating valves, and closing the outlet valve, so as to couple the upstream and downstream piping in a closed fluid circuit with the chamber via the recirculation path, thereby directing drying fluid exiting the chamber through the dehumidifier to the upstream piping.

US Pat. No. 9,909,696

TECHNIQUES FOR JOINING LINED PIPELINES

Subsea 7 Limited, Sutton...

1. A method of assembling a pipeline joint, comprising:
providing a first lined pipe whose liner comprises:
a body section; and
an end section of lesser thickness and greater bore than the body section;
inserting into the end of the first pipe a connector comprising:
a tube having opposed ends, the tube defining opposed male interface elements extending inwardly from respective ends of the
tube; and

at least one circumferential permeable choke projecting radially from each male interface element to control fluid flow around
the tube in use;

such that one male interface element of the connector is received telescopically by the end section of the liner with the
choke extending radially between the male interface element and the end section, while leaving the opposed male interface
element protruding from the end of the first pipe;

bringing a second lined pipe into end-to-end abutting relation with the first pipe, the liner of the second pipe having a
corresponding body section and end section such that the opposed male interface element of the connector is received telescopically
by the end section of the liner of the second pipe, with the choke of the opposed male interface element extending radially
between that male interface element and that end section; and

joining the pipes where they abut end-to-end.

US Pat. No. 9,857,011

CONNECTIONS FOR SUBSEA PIPE-IN-PIPE STRUCTURES

Subsea 7 Limited, Sutton...

1. A reelable connection between facing ends of opposed pipe sections of a subsea pipeline, the connection being configured
to be reeled and then subsequently unreeled from a pipeline reel to return to its original shape, each pipe section being
of pipe-in-pipe construction comprising an inner pipe disposed within, and extending longitudinally along, an outer pipe that
defines an outer pipe diameter; wherein:
the outer pipe includes an end wall that is defined by an inwardly-inclined end portion of the outer pipe and is formed as
a one-piece, homogeneous structure with the outer pipe, the end wall connecting the inner and outer pipes of each pipe section
to seal an end of an annular space defined between those pipes;

the inner pipe of each pipe section protrudes longitudinally beyond the end wall and the outer pipe of that pipe section and
is joined to an inner pipe of the opposed pipe section, leaving opposed ends of the outer pipes of the pipe sections spaced
longitudinally from each other; and

a substantially flush insert disposed between the opposed ends of the outer pipes maintains the outer pipe diameter from one
pipe section to the other pipe section across the connection to facilitate reeling and unreeling of the pipe sections, wherein
the insert has one end welded to one of the opposed outer pipes or to the end wall of that outer pipe, and another end welded
to the other of the opposed outer pipes or to the end wall of that other outer pipe.

US Pat. No. 9,114,858

SUBSEA ANCHORING ASSEMBLY

Subsea 7 Limited, Sutton...

8. A subsea anchoring assembly, comprising:
an anchor;
a locking head for connection of a mooring line to the anchor; and
a socket provided on the anchor and having a seat adapted to receive and seat the locking head within the socket;
the socket having a neck provided with a guide device to direct the locking head into alignment with the socket;
wherein the locking head and the socket can move between a first configuration in which the locking head and the socket are
separate, and a second configuration in which the locking head and the socket are locked together; and

the anchoring assembly further comprising a ramp adapted to guide the head or the mooring line through the neck and into the
socket, wherein the seat on the socket faces the ramp.

US Pat. No. 9,719,613

PIPELAYING

Subsea 7 Limited, Sutton...

1. A method of clamping elongate elements in a parallel piggybacked arrangement during subsea laying of the elements, the
method comprising forcing together a plurality of clamp segments around the elongate elements by moving a pair of opposed
jaws towards one another to apply assembly force locally to the clamp segments at different locations of the clamp segments
in a direction orthogonal to a launch direction of the elongate elements, those locations being disposed to either side of
portions of the clamp segments that accommodate at least one of the elongate elements to assemble a piggybacking clamp that
applies clamping forces to the elongate elements, and further comprising supporting the jaws on a carriage that moves in the
launch direction during clamping to allow the clamp segments to move with the elongate elements in the launch direction while
forcing the clamp segments together around the elongate elements.

US Pat. No. 9,909,689

PIPELAYING

Subsea 7 Limited, Sutton...

1. A mudmat for a subsea pipeline accessory, the mudmat comprising:
a body having an accessory support structure arranged to lie underneath and support an accessory; and
at least one foundation element attached to the body and movable from a stowed position at least partially under the accessory
support structure into a deployed position extending laterally from the accessory support structure,

wherein the at least one foundation element is supported for rotation relative to the body during movement into the deployed
position.

US Pat. No. 9,909,690

TRANSPORTATION AND INSTALLATION OF ELONGATE SUBSEA ELEMENTS

Subsea 7 Limited, Sutton...

1. A method of handling a discrete elongate subsea element of determinate length for transport or installation, the method
comprising:
shortening a tensile chord system acting on longitudinally-spaced locations on the element to apply longitudinally-compressive
forces to the element, which forces bend the element along its length between said locations against elastic recovery force
to shorten a span of the element;

anchoring a first end of the element at a first anchorage located at a subsea installation before or after said bending of
the element; and

after said bending of the element and while the element remains bent, anchoring a second end of the element at a second anchorage
located at the subsea installation.

US Pat. No. 9,944,370

SUBSEA HOSTING OF UNMANNED UNDERWATER VEHICLES

Subsea 7 Limited, Sutton...

1. A method of hosting an autonomous underwater vehicle (AUV) at a subsea location, the method comprising:lowering at least one AUV basket, without self-propulsion, to a subsea location adjacent at least one pre-installed subsea structure, which structure has provision for electrical power to be provided to it;
at the subsea location, connecting the, or each, basket to a subsea structure by extending a power cable from the, or each, basket toward the subsea structure to receive electrical power from the subsea structure; and
using electrical power routed via the subsea structure to charge batteries of an AUV docked with the basket.

US Pat. No. 10,174,865

TOWABLE SUBSEA OIL AND GAS PRODUCTION SYSTEMS

Subsea 7 Limited, Sutton...

1. A towable pipeline bundle for installation underwater at a subsea oil or gas production site, the bundle comprising:two or more flowlines for carrying production fluid bundled in parallel relation;
at least one rigid buoyancy pipe extending along and supporting said bundled flowlines, which buoyancy pipe has an internal buoyancy chamber and at least one port for introducing fluid into the buoyancy chamber;
one or more spacer frames supporting and locating the flowlines relative to the buoyancy pipe and spacing each flowline from each other flowline, the or each spacer frame being attached to and extending transversely from or within the buoyancy pipe; and
wherein the buoyancy pipe is of polymer-composite material and is arranged to have positive buoyancy in seawater when its buoyancy chamber contains a fluid less dense than seawater.

US Pat. No. 10,215,324

METHOD OF AND SYSTEM FOR COATING A FIELD JOINT OF A PIPE

Subsea 7 Limited, Sutton...

1. A method of coating a field joint of a pipeline, the method comprising:placing at least one body comprising a thermoplastics material around the field joint;
assembling two or more mould tool elements around the field joint to make a mould tool that defines a mould cavity;
heating the body in the mould cavity around the field joint to effect thermal expansion of the thermoplastics material; and
constraining thermal expansion of the body in the mould cavity to apply elevated pressure between the body and pipe sections joined at the field joint, and then removing the mould tool from around the field joint;
wherein:
the mould cavity has a first volume;
on being placed around the field joint, the body has a second volume such that the body can fit into the mould cavity; and
the thermoplastics material of the body has a positive coefficient of thermal expansion such that, when heated in the mould cavity, the body would expand from the second volume to a third volume greater than the first volume if such thermal expansion were not constrained.

US Pat. No. 9,988,129

TRANSMISSION OF POWER UNDERWATER

Subsea 7 Limited, Sutton...

1. A method of providing electric power to subsea equipment underwater, the method comprising:temporarily coupling a rotary coupling element of a power unit to the subsea equipment;
effecting electromagnetic coupling between the rotary coupling element of the power unit and a stator of the subsea equipment by bringing together the rotary coupling element of the power unit and the stator of the subsea equipment, the electromagnetic coupling of the rotary coupling element of the power unit and the stator of the subsea equipment forms a generator that generates the electric power on board the subsea equipment upon rotation of the rotary coupling element of the power unit;
turning the rotary coupling element to generate electric power on board the subsea equipment; and
stabilizing the power unit and/or the subsea equipment against torque reaction forces by effecting a secondary attachment between the power unit and the subsea equipment.

US Pat. No. 10,174,866

APPARATUS AND METHOD FOR SUBSEA LIQUID MIXING AND SAMPLING

Subsea 7 Limited, Sutton...

1. A subsea-submersible mixing and sampling apparatus, comprising:submersible supply systems for first and second liquid components, each supply system comprising a respective submersible reservoir for holding a respective one of those liquid components, wherein the submersible reservoirs of the submersible supply systems are pressure-compensated or collapsible;
at least one submersible mixer downstream of the supply systems for mixing the first and second liquid components to form a mixture for curing;
at least one submersible sampling device downstream of the or each mixer for taking a sample of the mixture underwater; and
at least one injection outlet downstream of at least one of the mixers for injecting the mixture into a subsea chamber to which the injection outlet may be connected in use, wherein the injection outlet and a sampling device are on parallel flowpaths downstream of said mixer.

US Pat. No. 10,107,078

CONNECTION AND DISCONNECTION OF HYDRAULIC EQUIPMENT IN HYPERBARIC ENVIRONMENTS

Subsea 7 Limited, Sutton...

1. A hydraulically-powered tool system for subsea interventions, the system comprising:a tool communicating with a first connector element, the tool and the first connector element being on a hydraulic drive circuit; and
a tool power unit having a hydraulic supply circuit communicating with a second connector element, the first and second connector elements being arranged to be wet-mated with each other to establish fluid communication between the supply circuit and the drive circuit for powering movement of one or more elements of the tool when in use;
wherein:
the drive circuit is pressure-compensated by a drive circuit compensator, minimizing a pressure difference between the drive circuit and a hydrostatic pressure of surrounding environment;
the supply circuit is pressure-compensated by a supply circuit compensator, minimizing a pressure difference between the supply circuit and a hydrostatic pressure of surrounding seawater; and
the system further comprises at least one valve that, when the drive circuit and the supply circuit are in fluid communication, is operable to transfer pressure compensation of one of said circuits from the compensator of that circuit to the compensator of the other circuit.