U.S. patent application number 11/579224 was filed with the patent office on 2007-10-04 for flying lead connector and method for making subsea connections.
Invention is credited to Lionel M. Fontenette, Mario R. Lugo.
Application Number | 20070227740 11/579224 |
Document ID | / |
Family ID | 34956099 |
Filed Date | 2007-10-04 |
United States Patent
Application |
20070227740 |
Kind Code |
A1 |
Fontenette; Lionel M. ; et
al. |
October 4, 2007 |
Flying Lead Connector and Method for Making Subsea Connections
Abstract
The present invention generally provides a rigid flying lead.
The improved flying lead arrangement is configured to provide fluid
communication between a first item of subsea equipment and a second
item of subsea equipment in a marine body. In one embodiment, the
flying lead includes a first substantially rigid end kit disposed
at a first end of the flying lead, and a second substantially rigid
end kit disposed at a second end of the flying lead. A
substantially rigid midsection is defined between the first end kit
and the second end kit. At least one, and preferably multiple,
fluid communication lines are disposed within the midsection,
providing fluid communication between the two items of subsea
equipment. Examples of subsea equipment include an umbilical end
termination, a subsea distribution unit, a subsea tree and a
manifold. The flying lead is configured to be lowered into a marine
body using a spreader bar so that junction plates on the respective
end kits can be gravitationally landed into respective junction
plate receptacles.
Inventors: |
Fontenette; Lionel M.;
(Humble, TX) ; Lugo; Mario R.; (Houston,
TX) |
Correspondence
Address: |
Brent R. Knight;ExxonMobil Upstream Research Company
P.O.Box 2189 (CORP-URC-SW337)
Houston
TX
77252-2189
US
|
Family ID: |
34956099 |
Appl. No.: |
11/579224 |
Filed: |
May 9, 2005 |
PCT Filed: |
May 9, 2005 |
PCT NO: |
PCT/US05/15989 |
371 Date: |
October 31, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60571276 |
May 14, 2004 |
|
|
|
Current U.S.
Class: |
166/344 |
Current CPC
Class: |
E21B 33/038 20130101;
E21B 41/04 20130101; E21B 43/013 20130101 |
Class at
Publication: |
166/344 |
International
Class: |
E21B 41/04 20060101
E21B041/04 |
Claims
1. A flying lead for providing fluid communication between a first
item of subsea equipment and a second item of subsea equipment in a
marine body, the flying lead comprising: a first substantially
rigid end kit disposed at a first end of the flying lead; a second
substantially rigid end kit disposed at a second end of the flying
lead; and a substantially rigid and substantially linear midsection
providing two or more fluid communication lines between the first
end kit and the second end kit; wherein each of the first and
second end kits is configured to be landed into a respective first
and second item of subsea equipment by lowering the flying lead
into the marine body with a spreader bar.
2. The flying lead of claim 1, wherein each of the first and second
end kits comprises: an end kit connector for receiving a releasable
connection with the spreader bar.
3. The flying lead of claim 2, wherein the end kit connector on
each of the first and second end kits defines a pad eye.
4. The flying lead of claim 1, wherein the first end kit comprises:
a first end and a second end; a junction plate configured to land
into a junction plate receptacle at the first item of subsea
equipment; and at least two end kit communication lines each having
a first end and a second end, the first end of each of the at least
two end kit communication lines being in fluid communication with a
receptacle on the junction plate, and the second end of each of the
at least two end kit communication lines being in fluid
communication with a respective one of the one or more fluid
communication lines in the midsection of the flying lead.
5. The flying lead of claim 4, wherein: the junction plate is a
multi-coupler junction plate; and the at least one two kit
communications line comprise at least two separate metal-encased
communication lines.
6. The flying lead of claim 1, wherein the first end kit comprises:
a first end and a second end; a multi-coupler junction plate
disposed proximate to the first end of the first end kit, and
configured to land into a junction plate receptacle at the first
item of subsea equipment; and at least two metal-encased end kit
communication lines each having a first end and a second end, the
first end of each of the at least two end kit communication lines
being in fluid communication with a receptacle on the junction
plate, and the second end of each of the at least two end kit
communication lines being in fluid communication with a respective
fluid communication line in the midsection of the flying lead.
7. The flying lead of claim 7, wherein the first end kit further
comprises: a locating pin configured to land into a locating pin
receptacle at the first item of subsea equipment.
8. The flying lead of claim 1, further comprising a locating pin
for a locating assembly.
9. The flying lead of claim 8, wherein the locating pin further
comprises: a first end connected to a frame of the first end kit;
and a second end configured to gravitationally land into a locating
pin receptacle at the first item of subsea equipment.
10. The flying lead of claim 1, further comprising a locating pin,
the locating pin having: a first end connected to a frame of the
first end kit; a second end configured to gravitationally land into
a locating pin receptacle at the first item of subsea equipment;
and a key dimensioned to land on and to ride along a shoulder of
the locating pin receptacle.
11. The flying lead of claim 1, wherein the first end kit
comprises: a connector for receiving a releasable connection with
the spreader bar; an upper frame section; a multi-coupler junction
plate disposed on the upper frame section, and configured to land
into a junction plate receptacle at the first item of subsea
equipment; a lower frame section configured to be attached to the
midsection in a substantially horizontal orientation along the
bottom of the marine body; an intermediate frame section connected
to the upper and lower frame sections; and at least two
metal-encased end kit communication lines each having a first end
and a second end, the first end of each of the at least two end kit
communication lines being in fluid communication with fluid
couplers on the junction plate, and the second end of each of the
at least two end kit communication lines being in fluid
communication with respective fluid communication lines in the
midsection of the flying lead.
12. The flying lead of claim 11, wherein the upper, lower and
intermediate frame sections are each fabricated out of a metallic
substance.
13. The flying lead of claim 11, wherein the upper frame section
and the intermediate frame sections connect to form an essentially
right angle.
14. The flying lead of claim 11, wherein the intermediate frame
section connects to a riser casing, the riser casing in turn being
connected to the lower frame section.
15. The flying lead of claim 11, further comprising a bushing
providing a flex-limited connection between the upper frame section
and the intermediate frame section.
16. The flying lead of claim 6, wherein: the two or more
communication lines comprises at least two fluid communication
lines having different inner diameters; and at least one of the
communication lines is fabricated from heavy wall tubing.
17. The flying lead of claim 6, wherein at least one of the two or
more communication lines comprises a fluid communication line
having an inner diameter of at least one inch.
18. An end kit for a flying lead, the flying lead providing fluid
communication between a first item of subsea equipment and a
midsection having at least two fluid communication lines, the end
kit comprising: at least one rigid frame section; a connector
disposed on the at least one rigid frame section for receiving a
releasable connection with a spreader bar; and a multi-coupler
junction plate also disposed on the at least one rigid frame
section, and configured to gravitationally land into a junction
plate receptacle in an item of subsea equipment.
19. The end kit of claim 18, wherein the connector on the at least
one rigid frame section defines a pad eye.
20. The end kit of claim 18, further comprising at least two fluid
communication lines each have a first end and a second end, the
first end of each of the end kit fluid communication lines being in
fluid communication with a receptacle on the junction plate, and
the second end of each of the end kit fluid communication lines
being in fluid communication with a respective fluid communication
line of the midsection.
21. The end kit of claim 18, further comprising a locating pin
configured to land into a locating pin receptacle at the item of
subsea equipment.
22. The end kit of claim 21, wherein the locating pin has a first
end connected to the at least one rigid frame section, and a second
end configured to land into a locating pin receptacle at the first
item of subsea equipment.
23. The end kit of claim 18, wherein: the at least one rigid frame
section defines an upper frame section, an intermediate frame
section and a lower frame section, with the junction plate being
disposed on the upper frame section, the lower frame section being
configured to be attached to the midsection in a substantially
horizontal orientation along the bottom of the marine body, and the
intermediate frame section being connected to the upper and lower
frame sections; and wherein the end kit further comprises at least
two metal-encased end kit communication lines each having a first
end and a second end, the first end of each of the at least two end
kit communication lines being in fluid communication with a
respective receptacle on the junction plate, and the second end of
each of the end kit fluid communication lines being in fluid
communication with a respective fluid communication line of the
midsection.
24. The end kit of claim 23, wherein the upper frame section and
the intermediate frame section connect to form an essentially right
angle.
25. The end kit of claim 23, wherein the intermediate frame section
connects to a riser casing, the riser casing in turn being
connected to the lower frame section.
26. The end kit of claim 23, further comprising a flexible bushing
providing a limited-pivoting connection between the upper frame
section and the intermediate frame section.
27. The end kit of claim 18, further comprising a locating
assembly.
28. The end kit of claim 18, further comprising a locating
assembly, the locating assembly comprising: a locating pin disposed
along the first rigid frame section; and a receptacle configured to
receive the locating pin, the receptacle residing on the item of
subsea equipment.
29. The end kit of claim 18, further comprising a locating
assembly, the locating assembly comprising: a locating pin disposed
along the first rigid frame section; a key disposed along an outer
diameter of the locating pin; a receptacle configured to receive
the locating pin, the receptacle residing on the item of subsea
equipment; and a shoulder along an inner diameter of the
receptacle, the shoulder configured to receive the key and direct
it into a slot.
30. The end kit of claim 29, wherein the shoulder is bi-helically
arranged.
31. A method for installing a flying lead, the flying lead
providing fluid communication between a first item of subsea
equipment and a second item of subsea equipment in a marine body,
the method comprising the steps of: placing a flying lead onto a
vessel, the flying lead comprising: a first rigid end kit disposed
at a first end of the flying lead, the first rigid end kit having a
fluid communication line secured therein, a second rigid end kit
disposed at a second end of the flying lead, the second rigid end
kit also having a fluid communication line secured therein, and a
substantially rigid and substantially linear midsection also having
a fluid communication line disposed therein, the midsection fluid
communication line having a first end in fluid communication with
the fluid communication line of the first end kit, and a second end
in fluid communication with the fluid communication line of the
second end kit, and wherein each of the first and second end kits
is configured to be landed into a receptacle at a respective first
and second item of subsea equipment by lowering the flying lead
into the marine body with a spreader bar; locating the vessel at a
selected location generally above the first and second items of
subsea equipment; releasably securing the flying lead to a spreader
bar; lowering the spreader bar and connected flying lead into the
marine body; positioning the first end kit above the first item of
subsea equipment; landing the first end kit into the first item of
subsea equipment; establishing fluid communication between the
fluid communication line of the first end kit, and the first item
of subsea equipment; positioning the second end kit above the
second item of subsea equipment; landing the second end kit into
the second item of subsea equipment; establishing fluid
communication between the fluid communication line of the second
end kit, and the second item of subsea equipment, thereby
establishing fluid communication between the first and second items
of subsea equipment.
32. The method of claim 31, wherein the first end kit and the
second end kit each further comprises: at least one rigid frame
section; a connector disposed on the at least one rigid frame
section for receiving a releasable connection with the spreader
bar; and a junction plate also disposed on the at least one rigid
frame section, and configured to land into a junction plate
receptacle in an item of subsea equipment.
33. The method of claim 31, wherein: the communication line of the
first end kit is in fluid communication with the junction plate
receptacle on the first end kit; and the communication line of the
second end kit is in fluid communication with the junction plate
receptacle on the second end kit.
34. The method of claim 31, wherein: each junction plate is a
multi-coupler junction plate having multiple receptacles for
receiving fluid communication lines; the first end kit comprises at
least two fluid communication lines; the second end kit comprises
at least two fluid communication lines; and the midsection
comprises at least two fluid communication line.
35. The method of claim 31, wherein: the first end kit further
comprises a locating pin configured to land into a locating pin
receptacle at the first item of subsea equipment; and the second
end kit further comprises a locating pin configured to land into a
locating pin receptacle at the second item of subsea equipment.
36. The method of claim 35, wherein: the locating pin of the first
end kit has a first end connected to the at least one rigid frame
section of the first end kit, and a second end configured to land
into a locating pin receptacle at the first item of subsea
equipment; and the locating pin of the second end kit has a first
end connected to the at least one rigid frame section of the second
end kit, and a second end configured to land into a locating pin
receptacle at the second item of subsea equipment.
37. The method of claim 36, wherein: the locating pin of the first
end kit further comprises a key dimensioned to land on and to ride
along a shoulder of the locating pin receptacle at the first item
of subsea equipment; and the locating pin of the second end kit
further comprises a key dimensioned to land on and to ride along a
bi-helical shoulder of the locating pin receptacle at the second
item of subsea equipment.
38. The method of claim 31, further comprising the step of:
releasing the flying lead from the spreader bar.
39. The method of claim 38, wherein the step of releasing the
flying lead from the spreader bar is conducted before the step of
establishing fluid communication between the fluid communication
line of the first end kit and the first item of subsea
equipment.
40. The method of claim 31, wherein the first item of subsea
equipment is selected from the group consisting of an umbilical end
termination, a subsea distribution unit, a subsea tree and a
manifold.
41. The method of claim 31, further comprising the step of:
delivering fluid from the first item of subsea equipment to the
second item of subsea equipment through the flying lead.
42. The method of claim 41, wherein the fluid is selected from the
group consisting of hydraulic control fluid, chemical treatment
fluid, and gas for gas lift valves.
43. The method of claim 42, wherein: the fluid is a gas for gas
lift valves, and the gas is transmitted through a communication
line having a diameter greater than 1 inch.
44. The method of claim 42, wherein the chemical treatment fluid is
methanol.
45. The method of claim 31, wherein the step of establishing fluid
communication between the fluid communication line of the first end
kit, and the first item of subsea equipment, is accomplished by
using an ROV after the junction plate on the first item of subsea
equipment has gravitationally landed into the receptacle on the
first item of subsea equipment.
46. A flying lead for providing fluid communication between a first
item of subsea equipment and a second item of subsea equipment in a
marine body, the flying lead comprising: a substantially rigid and
substantially linear midsection, the midsection having a first end
and a second opposing end, and having a hydraulic line disposed
therein; a first end kit disposed at a first end of the midsection,
the first end kit having a steel-encased hydraulic line therein in
fluid communication with the hydraulic line of the midsection; a
second end kit disposed at a second end of the midsection, the
second end kit also having a steel-encased hydraulic line therein
and also being in fluid communication with the hydraulic line of
the midsection; and wherein the hydraulic lines of the midsection,
the first end kit and the second end kit each have an inner
diameter of at least one inch.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application 60/571,276, filed 14 May, 2004.
BACKGROUND
[0002] 1. Field of the Invention
[0003] Embodiments of the present invention generally relate to
subsea connections. Such connections may include subsea tie-in
monitoring lines, control lines and chemical injection lines.
Embodiments of the present invention further pertain to methods for
making subsea connections using flying lead connectors.
[0004] 2. Description of Related Art
[0005] Over the last thirty years, the search for oil and gas
offshore has moved into progressively deeper waters. Wells are now
commonly drilled at depths of several hundred feet and even several
thousand feet below the surface of the ocean. In addition, wells
are now being drilled in more remote offshore locations.
[0006] The drilling and maintenance of deep and remote offshore
wells is expensive. In an effort to reduce drilling and maintenance
expenses, remote offshore wells are oftentimes drilled in clusters.
A grouping of wells in a clustered subsea arrangement is sometimes
referred to as a "well-site." A well-site typically includes
producing wells completed for production at one and oftentimes more
pay zones. In addition, a well-site will oftentimes include one or
more injection wells to aid in maintaining reservoir pressure for
water drive and gas expansion drive reservoirs.
[0007] The grouping of subsea wells facilitates the gathering of
production fluids into a local production manifold. Fluids from the
clustered wells are delivered to the manifold through flowlines
called "jumpers." From the manifold, production fluids may be
delivered together to a gathering facility through a flow-line. The
clustering of wells also allows for multiple control lines and
chemical treatment lines to be run from the ocean surface, downward
to the clustered wells through one or more "umbilicals." The
umbilical terminates at an "umbilical termination assembly," or
"UTA," at the ocean floor The control line may carry hydraulic
fluid used for controlling items of subsea equipment such as subsea
distribution units ("SDU's"), manifolds and trees. Such control
lines allow the actuation of valves, chokes, downhole safety valves
and other subsea components from the surface. In addition, the
umbilical may transmit chemical inhibitors to the ocean floor and
then to equipment of the subsea processing system. The inhibitors
are designed and provided in order to ensure that flow from the
wells is not affected by the formation of solids in the flow stream
such as hydrates, waxes and scale. Electrical lines may also be
included in an umbilical for monitoring or control of subsea
functions.
[0008] In order to connect various communication lines, i.e.,
control lines and chemical injection lines, etc., to items of
equipment on the ocean floor, special connectors known as "flying
leads" are oftentimes employed. The flying leads connect the ends
of lines to subsea equipment, such as connecting to a control pod
on a manifold or subsea tree at one end to an umbilical termination
assembly at the other end. In shallow water, flying leads are
connected to the subsea equipment by divers. In deeper waters, one
or more remote operated vehicles (ROV) are utilized.
[0009] Different configurations for flying leads are presently
available. Two general types of flying leads for interconnecting
the elements of a subsea cluster production system are Hydraulic
Flying Leads, or "HFL's," and Steel Flying Leads, or "SFL's." Both
types of leads may house lines for monitoring, control and, when
necessary, chemical injection in the subsea system. Each type of
lead has benefits and limitations.
[0010] HFL leads commonly are made up of thermoplastic hoses of
various sizes and configurations. In one known arrangement, a nylon
"Type 11" internal pressure sheath is utilized as the inner layer.
A reinforcement layer is provided around the internal pressure
sheath. One material used as the reinforcement layer is a double
braided aramid fiber, such as Kevlar. A polyurethane outer sheath
is bonded to the Kevlar. The polyurethane sheath provides water
proofing. Where additional collapse resistance is needed, a
stainless steel internal carcass is disposed within the internal
pressure sheath. An example of such an internal carcass is a spiral
wound interlocked 316 stainless steel carcass.
[0011] End fittings are provided on each end of thermoplastic
hoses. The end fittings are typically crimped or swaged onto the
hose. Connected to the end fittings on each end of the hoses is a
multiple quick connect "MQC" junction plate. This MQC plate
provides the connection point between subsea equipment and
communication lines, and is usually installed last using ROV units
subsea. Bend restrictors are commonly added to the respective ends
of the hose, as needed. Subject to the use of bend restrictors, HFL
leads provide the benefit of flexibility which aids in
transportation, handling, and subsea installation. On the other
hand, HFL leads have inherent external pressure (collapse)
limitations, and can be subject to kinking. In addition, the use of
a metallic inner carcass induces large pressure drops across the
length of a hose. Further, the connection between the end fitting
and the hose requires a reduced diameter that restricts flow, and
is susceptible to erosion and clogging. Still further, the HFL hose
employs a screw-type fitting that is susceptible to leaking.
[0012] SFL leads presently being used commonly define a collection
of separate steel tubes bundled within a flexible vented plastic
tube. Typically, a "Cobra" type end connection containing a
multiple quick connect "MQC" junction plate connection is provided
at each end of the tubes. The individual tubes are routed into the
respective end connections and welded into socket fittings in the
opposing MQC junction plate connections. A bend restrictor is
fitted to each end. As noted, the MQC plates provide the final
connection point between the subsea components, and are usually
installed last by means of ROV units subsea.
[0013] Steel flying leads are able to tolerate higher external
pressures and lower temperatures. However, they suffer from a lack
of flexibility. As of this filing, the largest steel tubing line at
the end connection known to the inventors is 1/2'' in diameter.
Larger diameter lines make the end connections too stiff and
unmanageable during installation. Additionally, the bend radius
required for larger diameter tubing would place the end connections
too high above the seabed. Further, conventional steel flying leads
are not suitable for heavy wall tubing, as the end connections
become too stiff and unmanageable during installation. Conventional
SFL's are also difficult to install, and may be damaged during
installation. The difficulty of installing the SFL's makes them
susceptible to excessive installation vessel downtime. Conventional
SFL's further require more offshore equipment on deck of the vessel
during installation, which eliminates from consideration some
installation vessels with limited deck space. Finally, steel leads
are heavier than thermoplastic hoses, meaning that an ROV unit
having a greater capacity is required for installation. ROVs having
the needed horsepower range are not commonly available, and may
further restrict installation vessel options because normally the
only available ROVs of this power are permanently mounted on
vessels. Alternatively, the number and size of tubes used may be
limited due to remote operating vehicle (ROV) constraints.
[0014] Installation of an HFL lead or an SFL lead generally
requires the use of two ROV units. A first ROV carries an end of
the hose and docks to an MQC junction plate receptacle on the
subsea equipment. As the first ROV "flies" the end of the HFL to
the connection point, a second ROV observes the HFL at the
deployment frame in order to prevent damage to the HFL. Once
docked, the first ROV installs the HFL MQC junction plate
receptacle into an inboard junction plate on the manifold or other
subsea equipment.
[0015] There is a need for a flying lead arrangement that enjoys
the higher pressure ratings of conventional steel flying leads, but
is easier to install. There is further a need for a flying lead
arrangement that enjoys the pressure capacities of a steel flying
lead assembly, but which may optionally utilize flow lines greater
than 1/2'' in diameter, and which optionally may utilize an ROV
having a power rating normally associated with a lighter hydraulic
flying lead assembly.
SUMMARY
[0016] The present invention generally provides a rigid steel
flying lead. The improved flying lead arrangement is configured to
provide fluid communication between a first item of subsea
equipment and a second item of subsea equipment in a subsea
cluster. Non-limiting examples of subsea equipment include an
umbilical end termination, a subsea distribution unit, a subsea
tree and a manifold. In one embodiment, the flying lead includes a
first rigid end kit connected at a first end of the flying lead,
and a second rigid end kit connected at a second end of the flying
lead. A midsection is defined between the first end kit and the
second end kit. At least two, and preferably multiple, fluid
communication lines are disposed within the umbilical, providing
fluid communication between the two items of subsea equipment. The
communication lines comprise steel tubes or other rigid tubulars
connected in the first and second end kits and the midsection.
Additional communication lines may optionally be employed for
providing electrical or optical communication as may be employed
for monitoring or control of subsea components and conditions.
[0017] The first and second end kits are substantially rigid. This
allows them to more securely support opposing ends of the fluid
communication lines within the midsection, and allows the
communication lines to be fabricated from a rugged material such as
steel. The communication lines may also be of various
configurations, such has having an internal diameter of one inch or
greater. At least one of the communication lines may be fabricated
from a heavy wall tubing for conveying fluids under high pressure.
Preferably, each end kit houses a collection of separate steel
tubes in a structural steel housing, or "casing." MQC junction
plates continue to provide interface between the communication
lines and the selected subsea equipment. The rigid end kit
configuration allows each end kit to be gravitationally landed into
a junction plate receptacle at the respective first and second
items of subsea equipment by lowering the flying lead into the
marine body with a rigid structural member designed for this task.
An example of such a rigid structural member is a spreader bar.
[0018] The rigid SFL is optionally equipped with an alignment pin
at both end connections. The alignment pin includes a key that
lands into a receptacle. The receptacle includes a shoulder, such
as a "Y" shoulder or a helical shoulder, that orients the MQC
junction plates. The rigid flying lead is thereby caused to pivot
at the landing end in order to properly land the SFL at the second
end.
[0019] A method for making a subsea connection is also provided. A
flying lead in accordance with the present invention is placed onto
a vessel in a marine body. The respective first and second rigid
end kits connect fluid communication lines there between through a
substantially rigid and substantially linear midsection. The fluid
communication lines may be integral through the midsection and
opposing end kits, or may be separate collections of lines that are
welded together to form continuous fluid communication lines. Each
of the first and second end kits is configured to be
gravitationally landed into a receptacle at a respective first and
second item of subsea equipment by lowering the flying lead into
the marine body with a spreader bar.
[0020] The vessel having the flying lead is located at a selected
location generally above the first and second items of subsea
equipment. The flying lead is releasably secured to a spreader bar.
The spreader bar and connected flying lead are then lowered into
the marine body. The first end kit is positioned above the first
item of subsea equipment, and then landed. Next, the second end kit
is positioned above the second item of subsea equipment and landed.
Fluid communication is then established between the fluid
communication lines of the first end kit and the first item of
subsea equipment, and between the fluid communication lines of the
second end kit and the second item of subsea equipment. In this
manner, fluid communication is established between the first and
second items of subsea equipment. In one embodiment, the steps for
providing fluid communication are conducted by actuating an MQC
junction plate connection with an ROV.
[0021] Because the flying lead is supported by the spreader bar,
only one ROV is required for landing the flying lead ends to the
subsea equipment. In addition, a lower power rating is permitted
for the ROV than for many flying lead installation operations. This
aspect is further enhanced when the respective end kits include the
optional alignment pin. The key on the alignment pin orients the
MQC junction plates and rotates the rigid flying lead at one end of
the line as needed to align and land the second end. In addition,
the same spreader bar and lift rigging used for a flowline jumper
installation may be used for the rigid steel flying lead ("SFL")
installation. As the first end is lowered into its receptacle, the
alignment key/shoulder assembly helps rotate the second end into
proper orientation, resulting in minimal ROV involvement and power
requirement. Installation time is thereby minimized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] A description of certain embodiments of the inventions is
presented below. To aid in this description, drawings are provided,
as follows:
[0023] FIG. 1 presents a plan view of a subsea cluster production
system, or well site. The illustrative cluster production system
includes four producing wells, with flowline jumpers delivering
produced fluids into a manifold. Flying leads deliver fluids such
as hydraulic control fluids or chemical inhibitors to the
individual wells and to the manifold through a central distribution
unit.
[0024] FIG. 2 presents a side view of a flying lead end kit, in one
embodiment. The end kit includes a locating pin and an MQC junction
plate. The locating pin is positioned over a pin receptacle for
landing, while the MQC junction plate is positioned vertically over
an MQC junction plate receptacle for landing.
[0025] FIGS. 2A and 2B provide enlarged cross-sectional views of a
portion of the end kit of FIG. 2 at the interface with the
midsection. In FIG. 2A, the connection between the communication
lines of the end kit and the communication lines of the midsection
are seen, with illustrative elbow joint welds. A lower connection
bracket welded to the metal housings is also seen. In FIG. 2B, the
open end to the midsection is seen.
[0026] FIG. 3 provides a cross-sectional view of the flying lead
end kit of FIG. 2. Here, the locating pin is about to land into the
receptacle. However, the MQC junction plate has not yet landed into
the MQC junction plate receptacle.
[0027] FIG. 4 presents a next step in the installation of the
flying lead of FIG. 2. In this view, the locating pin of the end
kit has landed into the receptacle on the subsea equipment. In
addition, the MQC junction plate has gravitationally landed into
the MQC junction plate receptacle. Couplers remain retracted,
indicating that the junction plate is not yet "locked."
[0028] FIG. 5A presents an enlarged, cross-sectional view of an
illustrative junction plate landed into the junction plate
receptacle. The plate has landed, but fluid communication has not
been established through the receptacle. FIG. 5B presents yet a
further enlarged cross-sectional view of the plate and receptacle
of FIG. 5A.
[0029] FIG. 6A presents an enlarged, cross-sectional view of the
junction plate of FIG. 5A, landed into the junction plate
receptacle. Here, fluid communication has been established through
the receptacle. FIG. 6B presents yet a further enlarged
cross-sectional view of the plate and receptacle of FIG. 6A.
[0030] FIGS. 7A-7G (1) and (2) provide enlarged, cross-sectional
views of the locating pin and receptacle. These figures depict
steps for landing and orienting the locating pin into the
receptacle. In FIG. 7A(1), the locating pin is positioned
vertically over the receptacle. FIG. 7A(2) presents a top view of
the locating pin. An orienting key is seen along the outer diameter
of the pin.
[0031] FIG. 7B is provided to demonstrate that the locating pin is
configured to accommodate a degree of misalignment during the
landing step.
[0032] In FIG. 7C(1), the locating pin is lowered partially into
the receptacle. The key on the locating pin has landed onto a
helical shoulder in the receptacle. FIG. 7C(2) provides a top view
of the pin landing on the helical shoulder.
[0033] FIGS. 7D-7F demonstrate the further lowering of the locating
pin into the receptacle. The key rides downward along the helical
shoulder, providing proper orientation for the flying lead. The
"(1)" series of the figures provide a side view, while the "(2)"
series figures show a plan view. Finally, in FIGS. 7F(1)-(2) and
7G(1)-(2), the locating pin has fully landed into the receptacle.
The key has landed into a bottom slot along the helical shoulder.
FIGS. 7F(1)-(2) and FIGS. 7G(1)-(2) provide the same step, but at a
different radial side views.
[0034] FIG. 8 presents a flying lead end kit, in an alternate
embodiment. In this arrangement, a sheer pin is utilized in the
locating pin. A swivel joint between the upper housing and the
intermediate frame can also be seen. A flex-limiter is optionally
disposed at the end of the intermediate frame.
[0035] FIGS. 9A-9C are provided to depict installation of an
embodiment of the flying lead into a subsea production system. In
FIG. 9A, the flying lead is being lowered towards two items of
production equipment on an ocean bottom. Each end of the flying
lead is being positioned over a respective receptacle. One end is
positioned over a receptacle on a subsea tree, while the other end
is being positioned over a receptacle on a SDU. FIG. 9B shows that
one end kit has landed into the receptacle on the subsea tree. In
FIG. 9C, the other end kit has landed into the receptacle on the
SDU. Installation of the flying lead is now complete.
[0036] FIG. 10 is a top view of the subsea equipment of FIG. 9C. In
this view, the subsea tree and the SDU are seen in plan. The
spreader bar supporting the flying lead is also seen between the
tree and the SDU.
DETAILED DESCRIPTION
Description of Specific Embodiments
[0037] The following provides a description of specific embodiments
of the present invention:
[0038] A flying lead is provided herein. The flying lead enables
fluid communication between a first item of subsea equipment and a
second item of subsea equipment in a marine body. The flying lead
generally includes a first substantially rigid end kit disposed at
a first end of the flying lead; a second substantially rigid end
kit disposed at a second end of the flying lead; and a
substantially rigid and substantially linear midsection. The
midsection conveys two or more fluid communication lines between
the first end kit and the second end kit. In addition, each of the
first and second end kits is configured to be landed into a
respective first and second item of subsea equipment by lowering
the flying lead into the marine body with a spreader bar.
[0039] Preferably, each of the first and second end kits of the
flying lead has an end kit connector for receiving a releasable
connection with the spreader bar. In addition, it is preferred that
at least one of the end kits includes a first end and a second end;
a junction plate configured to land into a junction plate
receptacle at the first item of subsea equipment; and at least two
end kit communication lines each having a first end and a second
end, the first end of each of the at least two end kit
communication lines being in fluid communication with a receptacle
on the junction plate, and the second end of each of the at least
two end kit communication lines being in fluid communication with a
respective one of the one or more fluid communication lines in the
midsection of the flying lead. Preferably, the junction plate is a
multi-coupler junction plate.
[0040] Preferably, at least one of the end kits further includes a
locating pin configured to land into a locating pin receptacle at
the first item of subsea equipment. The locating pin, in one
embodiment, has a first end connected to a frame of the first end
kit; a second end configured to gravitationally land into a
locating pin receptacle at the first item of subsea equipment; and
a key dimensioned to land on and to ride along a shoulder of the
locating pin receptacle.
[0041] In one embodiment, at least one of the end kits for the
flying lead includes a connector for receiving a releasable
connection with the spreader bar; an upper frame section; a
multi-coupler junction plate disposed on the upper frame section,
and configured to land into a junction plate receptacle at the
first item of subsea equipment; a lower frame section configured to
be attached to the midsection in a substantially horizontal
orientation along the bottom of the marine body; an intermediate
frame section connected to the upper and lower frame sections; and
at least two metal-encased end kit communication lines each having
a first end and a second end, the first end of each of the at least
two end kit communication lines being in fluid communication with
fluid couplers on the junction plate, and the second end of each of
the at least two end kit communication lines being in fluid
communication with respective fluid communication lines in the
midsection of the flying lead. The upper, lower and intermediate
frame sections are preferably each fabricated out of a metallic
substance. Preferably, the upper frame section and the intermediate
frame sections connect to form an essentially right angle. The
intermediate frame section may connect to a riser casing, with the
riser casing in turn being connected to the lower frame section. A
flex-limited connection may be provided between the upper frame
section and the intermediate frame section.
[0042] In one arrangement of the flying lead, two or more
communication lines comprise at least two fluid communication lines
having different inner diameters, and at least one of the
communication lines is fabricated from heavy wall tubing. In one
arrangement, at least one of the two or more communication lines
comprises a fluid communication line having an inner diameter of at
least one inch.
[0043] In another embodiment, a flying lead is disclosed for
providing fluid communication between a first item of subsea
equipment and a midsection having at least two fluid communication
lines. The flying lead generally includes at least one rigid frame
section; a connector disposed on the at least one rigid frame
section for receiving a releasable connection with a spreader bar;
and a multi-coupler junction plate also disposed on the at least
one rigid frame section, and configured to gravitationally land
into a junction plate receptacle in an item of subsea equipment. In
one instance, the end kit includes at least two fluid communication
lines, each have a first end and a second end. The first end of
each of the end kit fluid communication lines is in fluid
communication with a receptacle on the junction plate, while the
second end of each of the end kit fluid communication lines is in
fluid communication with a respective fluid communication line of
the midsection.
[0044] The at least one rigid frame section of the end kit may
define an upper frame section, an intermediate frame section and a
lower frame section, with the junction plate being disposed on the
upper frame section, the lower frame section being configured to be
attached to the midsection in a substantially horizontal
orientation along the bottom of the marine body, and the
intermediate frame section being connected to the upper and lower
frame sections. In addition, the end kit may further comprise at
least two metal-encased end kit communication lines each having a
first end and a second end. The first end of each of the at least
two end kit communication lines is in fluid communication with a
respective receptacle on the junction plate, and the second end of
each of the end kit fluid communication lines is in fluid
communication with a respective fluid communication line of the
midsection.
[0045] A method for installing a flying lead is also provided. The
method generally includes the steps of placing a flying lead onto a
vessel, the flying lead having first and second opposite rigid end
kits, and a substantially rigid and substantially linear midsection
disposed there between. Each of the first and second end kits is
configured to be landed into a receptacle at a respective first and
second item of subsea equipment by lowering the flying lead into
the marine body with a spreader bar. Additional steps include
locating the vessel at a selected location generally above the
first and second items of subsea equipment; releasably securing the
flying lead to a spreader bar; lowering the spreader bar and
connected flying lead into the marine body; positioning the first
end kit above the first item of subsea equipment; landing the first
end kit into the first item of subsea equipment; establishing fluid
communication between a fluid communication line of the first end
it, and the first item of subsea equipment; positioning the second
end kit above the second item of subsea equipment; landing the
second end kit into the second item of subsea equipment; and
establishing fluid communication between a fluid communication line
of the second end kit, and the second item of subsea equipment,
thereby establishing fluid communication between the first and
second items of subsea equipment.
[0046] In one embodiment, the step of releasing the flying lead
from the spreader bar is conducted before the step of establishing
fluid communication between the fluid communication line of the
first end kit and the first item of subsea equipment. In another
embodiment, the method further provides the step of delivering
fluid from the first item of subsea equipment to the second item of
subsea equipment through the flying lead. In another embodiment,
the step of establishing fluid communication between the fluid
communication line of the first end kit and the first item of
subsea equipment is accomplished by using an ROV after the junction
plate on the first item of subsea equipment has gravitationally
landed into the receptacle on the first item of subsea
equipment.
[0047] The first item of subsea equipment may be selected from the
group consisting of an umbilical end termination, a subsea
distribution unit, a subsea tree and a manifold. The fluid may be
selected from the group consisting of hydraulic control fluid,
chemical treatment fluid, and gas for gas lift valves.
Definitions
[0048] The following words and phrases are specifically defined for
purposes of the descriptions and claims herein. To the extent a
claim term has not been defined, it should be given its broadest
definition that persons in the pertinent art have given that term
as reflected in printed publications, dictionaries and issued
patents.
[0049] "Flying lead" means any assembly that transports or
communicates either hydraulic (or other) control fluid, chemicals,
electrically conductive wiring, fiber optic lines, or any
combination thereof, between two items of subsea equipment.
However, the term "flying lead" excludes fluid connection
apparatuses that transport production fluids, such as "flowline
jumpers."
[0050] "Subsea equipment" means any item of equipment placed
proximate the bottom of a marine body as part of a subsea
well-site.
[0051] "Midsection" means any collection of lines for providing
hydraulic, chemical, fiber optic or electrical communication
through a marine body. In addition, the term "midsection" includes
integrated lines that provide any combination of hydraulic,
chemical, fiber optic or electrical communication. The midsection
may have a steel fabricated casing, a thermoplastic sheath, or be
composed of any other material that will provide for a
substantially rigid connection between first and second end kits of
a flying lead.
[0052] "End kit" means an assembly on a flying lead for providing
fluid communication between an item of subsea equipment, and
communication lines within a midsection.
[0053] "Marine body" means any body of water, such as salt water in
an ocean environment, or fresh water in a lake. Similarly, "subsea"
includes both an ocean body and a deepwater lake.
[0054] "Umbilical termination assembly" means any item of subsea
equipment that provides a termination point for one or more
umbilical lines. The umbilical termination assembly, or "UTA," may
be placed on an ocean bottom, a mud mat, a manifold, a suction
pile, or any other position proximate to the sea floor.
[0055] "Subsea distribution unit" means any item of subsea
equipment that provides at least hydraulic and/or chemical
distribution in a subsea production system.
[0056] "Subsea distribution unit" may be abbreviated as "SDU" or
"SDU."
[0057] "Subsea tree" means any collection of valves disposed over a
wellhead in a water body.
[0058] "Manifold" means any item of subsea equipment that gathers
produced fluids from one or more subsea trees, and delivers those
fluids to a separate collection point through a flowline.
[0059] "Spreader bar" means any elongated tool for suspending
opposing end kits and a connected midsection.
[0060] "Junction plate" means any apparatus that provides a
quick-connect for placing multiple set of communication lines in
communication with another set of communication lines. The
communication lines may include lines for communicating hydraulic
fluid, chemicals, electrical signals and fiber optic signals.
Description of Embodiments Shown in the Drawings
[0061] Described herein are flying leads for connecting subsea
equipment. Also described are methods for connecting subsea
equipment.
[0062] FIG. 1 presents a plan view of a subsea cluster production
system, or well site 10. The illustrative subsea well-site 10
includes four wells 12, 14, 16, 18. The illustrated wells 12, 14,
16, 18 represent producing wells. Flowlines, or "tree jumpers," 22
deliver produced fluids from the individual wells 12, 14, 16, 18 to
a manifold 20. The manifold 20 collects the produced fluids from
the individual wells 12, 14, 16, 18. In one arrangement, production
collected from jumpers 22 may be commingled, and then delivered to
either or both of production sleds 34. In the arrangement shown in
FIG. 1, production is selectively commingled, meaning that some
production is delivered to one of the first sleds 34, and some
production is commingled and delivered to the other of sleds 34. An
additional second production sled 32 may optionally be provided for
future cluster 10 expansion. Production would then be delivered to
the sleds 32, 34 via flowlines 24. From the sleds 34, production is
transported through flowlines 38 up to an offshore host platform
(not shown). Export flowline 36 may be provided in the future, and
is shown in broken lines to indicate that it is not currently
installed in the subsea cluster 10.
[0063] The subsea cluster production system 10 of FIG. 1 is
intended to be for purposes of example only. It is understood that
more or less than four wells may be clustered at the well site 10.
In addition, it is understood that one or more of the wells 12, 14,
16, 18 may be injection wells (water or gas) rather than production
wells, though the production system 10 would require a different
flowline architecture. Still further, it is understood that
production may be commingled into a single flowline at a manifold
and delivered directly to the offshore gathering facility (such as
an FPSO, not shown), or even to a land-based gathering facility. In
addition, it is understood that the manifold 20 may or may not have
extra slots for future wells or for tie-ins from other fields. The
exemplary manifold 20 includes slot 23 reserved for tie in with a
new flowline, to be potentially delivered in the future to a fourth
sled (not shown).
[0064] It is desirable for the operator of the subsea production
system 10 to be able to remotely control valves at the manifold 20.
It is also desirable that the operator be able to monitor subsea
conditions such as fluid temperature within the manifold 20. Those
of ordinary skill in the art will understand that manifold and sled
designs vary in sophistication and complexity, and may include
complex control and distribution systems, sometimes known as
"control pods." Control pods are modules that contain
electro-hydraulic controls, logic software, and communication
signal devices. A master computer in a host platform control room
(not shown) communicates with the subsea control pods to operate
the valves and other functions on the manifold to increase or
reduce flow rates, or to shut in the flow entirely, if needed.
[0065] It is desirable that the operator also be able to inject
chemicals into the manifold and the individual wellheads to
maintain flow assurance. Those of ordinary skill in the art
understand that in both oil and gas wells, water present in the
produced fluids can form natural gas hydrates. Hydrates are a
crystallized form of water and methane stabilized by high pressure.
In addition, at low temperatures the waxy paraffins in some crude
oils deposit on pipeline walls, constricting flows. To overcome
these conditions, the operator may inject paraffin inhibitors to
keep paraffins and waxes from solidifying or depositing in the flow
streams. In addition, the operator may inject methanol or glycol to
serve as a form of "antifreeze," preventing hydrates from forming.
Further, the operator may inject scale inhibitors and corrosion
inhibitors through flowline jumpers and subsea equipment.
[0066] FIG. 1 shows line 42' delivered from the host platform or
other source to an umbilical termination assembly ("UTA") 40'. Line
42' represents an integrated electrical/hydraulic umbilical. Line
42' provides conductive wires for providing power to subsea
equipment, and also provides hydraulic fluid needed to power subsea
functions. Exemplary line 42' also provides fiber optic or
electrical signal lines for monitoring well or other condition
requirements. Finally, line 42' may in the future provide chemicals
to be distributed through the system 10. Line 42' terminates at the
umbilical termination assembly 40'. From the SDU 50, flying lead
line 44' delivers fluids and, optionally, signals to a "UTA" 40.
From the SDU 50, flying leads 52, 54, 56, 58 connect to the
individual wells 12, 14, 16, 18, respectively. In addition, flying
lead 55 connects to the manifold 20 to deliver chemicals and to
provide power or control, as desired by the operator.
[0067] Certain components are included in FIG. 1 in broken lines.
Line 42'' represents a possible future hydraulic umbilical,
delivering hydraulic fluid to future termination box 40''. From the
termination box 40'', flying lead line 44'' also delivers fluids to
the SDU 50. Line 42'', box 40'' and flying lead 44'' are shown in
broken lines to indicate that they are not yet installed into the
subsea cluster 10.
[0068] The flying leads 52, 54, 55, 56, 58 of FIG. 1 represent
lines that are delivered by a spreader bar and an ROV 930 in
accordance with teachings herein. Each flying lead 52, 54, 55, 56,
58 includes a midsection (described below as component 130), and
opposing end kit sections (described below as components 110 and
210, respectively). These three components 110, 210, 130 are seen
together in the side views of FIGS. 9A-9C. The flying leads 52, 54,
55, 56, 58 may be low pressure hydraulic lines that deliver
chemicals, or they may be power lines for delivering electrical or
hydraulic power to subsea equipment such as wellhead valves. The
flying leads 52, 54, 55, 56, 58 can also provide high pressure flow
lines. The flying leads 52, 54, 55, 56, 58 may include fiber optic
or electrical lines for monitoring subsea sensors. In addition, the
flying leads 52, 54, 55, 56, 58 may be integrated, providing
combinations of the above functions.
[0069] FIG. 2 presents a side view of a flying lead end kit 110, in
one embodiment. The end kit 110 is substantially rigid, providing
support for one or more steel-encased communication lines 115. In
this embodiment, rigidity is provided by various metal frame
structures. These frame structures include a lower housing 118, an
upper housing 113, and an intermediate housing 112. The end kit
110, in one arrangement, is welded to the midsection 130. A lower
connection bracket 111 provides additional support between the
lower housing 118 and a riser casing 112' around the intermediate
housing 112. In addition, an upper arm 114 provides additional
support for the upper housing 113.
[0070] The dimensions of the end kit 110 and its supporting frames
112 and 114 are determined based upon known dimensions of the
subsea equipment in which the end kit 110 is to be landed. The
corresponding item of subsea equipment is not shown in the
cross-sectional view of FIG. 2. However, illustrative items of
subsea equipment are shown in FIGS. 9A-9C, as will be described
below.
[0071] Measurements for spacing and orientation of subsea equipment
are typically performed using a remote operated vehicle ("ROV")
after subsea installation. The measurements may be performed at the
same time well and flowline jumpers are measured, with the same
field proven acoustic and taut line Pre-Measurement Tool ("PMT")
equipment and techniques. The same measurement data may be used for
fabricating jumpers and the flying lead 100, except that the PMT
azimuth angle, which is disregarded for jumper fabrication in some
cases, is used in fabricating the flying lead 100. Performing
flying lead measurements at the same time that the jumpers are
measured reduces installation cost. The measurements provide a
"straight line" distance between the subsea components. The rigid
design allows constructing the flying lead 100 in the same straight
line, resulting in the shortest possible midsection 130 length.
This further reduces installation costs, as well as fabrication
costs.
[0072] Referring again to FIG. 2, an optional intermediate frame
116 connected to the upper housing 113 may be provided. The
intermediate frame 116 surrounds the intermediate housing 112 at an
upper end. In this instance, an upper end of the intermediate
housing 112 is secured to the upper housing 113 by a swivel joint
116'. The swivel joint 116'' allows the intermediate housing 112 a
permissible amount of play relative to the upper housing 113. This,
in turn, accommodates minor deviations in subsea geography from PMT
data measurements. In addition, a separate riser casing may be
provided to surround and support the intermediate housing 112. Such
a riser casing is shown at 112' in FIG. 2. Longitudinal play is
permitted between the intermediate housing 112 and surrounding
riser casing 112' during fabrication and before subsea deployment
so that an appropriate vertical dimension for the flying lead 110
may be acquired.
[0073] FIGS. 2A and 2B provide enlarged cross-sectional views of
the end kit 110 of FIG. 2. In FIG. 2A, the connection between the
communication lines 115 of the end kit 110 and the communication
lines 135 of the midsection 130 are seen, with illustrative elbow
joint welds 133. The lower connection bracket 111 welded to the
metal riser casing 112' and lower frame 118 is also more fully
seen. In the preferred practice, the lower frame 118 is welded to
the mid-section 130 after the correct horizontal distance is
obtained. The lower connection bracket 111 is then lowered over the
lower frame 118 and fastened.
[0074] In FIG. 2B, an open end of the midsection 130 is seen. It is
important to note that, because of the rigid flying lead 100
fabrication, certain communication lines 135' may be dimensioned to
be larger and more pressure-resistant than currently employed
communication lines. Currently, known steel communication lines for
flying leads do not exceed 1/2 inches in diameter. Lines 135' are
intended to represent metal-encased communication lines having a
diameter of two or more inches. This new and larger geometry allows
the flying lead 100 to communicate larger amounts of chemicals
required in some fields without affecting the installation
operation. For example, in some remote offshore locations,
temperatures at the ocean bottom are so cold as to cause hydrates
to form, even when glycol or methanol is being injected through a
1/2 inch line. Increasing the size of the communication line 135'
allows larger amounts of glycol or methanol to be injected, thereby
inhibiting hydrate formation.
[0075] To provide further structural support for the enlarged
metal-encased communication lines 135', a support member 138 may be
placed in the midsection 130. In FIG. 2B, the support member 138 is
seen in cross-section, and is shaped as an "I-Beam".
[0076] Referring back to FIG. 2, the end kit 110 next includes a
junction plate 140. The junction plate 140 is designed to provide
fluid communication between the various communication lines 115 of
the first end kit 110, and valves or lines (not shown in FIG. 2) in
an item of subsea equipment (also not shown in FIG. 2). The
junction plate 140 lands into a junction plate receptacle 142. The
junction plate 140 includes connectors 144 for enabling fluid
communication from the communication lines 115 of the end kit 110.
Those of ordinary skill in the art will appreciate from this
disclosure that an ROV may then in one embodiment be utilized in
order to enable the latching of the junction plate 140 into the
receptacle 142 in order to provide operational fluid
communication.
[0077] In the arrangement of the end kit 110 of FIG. 2, the
junction plate 140 is a multi-quick connect junction plate, or "MQC
junction plate." The MQC junction plate 140 is placed at an end of
the end kit 110 along the upper arm 114. However, the scope of the
present invention is not limited to the arrangement for a junction
plate, or the precise location of the junction plate along the end
kit 110. The present invention only requires that the junction
plate 140 be gravitationally landed into the receptacle 142.
[0078] In order to enable actuation of the junction plate 140, an
indexing arm 119 is disposed along the upper frame arm 114. The
indexing arm 119 provides a point of latching for an ROV (not seen)
in order to do its work on the junction plate 140.
[0079] FIG. 5A presents an enlarged, cross-sectional view of the
junction plate 140 landed into a junction plate receptacle 142. The
plate 140 has landed, but fluid communication has not been
established with the receptacle 142. FIG. 5B presents yet a further
enlarged cross-sectional view of the plate 140 of FIG. 5A. It can
be seen from FIGS. 5A and 5B that a collet arrangement is utilized
in the landing of the junction plate 140. Collet arms 146 are seen
in cross-section.
[0080] FIG. 6A presents another enlarged, cross-sectional view of
the junction plate 140. The plate is again landed into the junction
plate receptacle 142. Fluid communication has now been established
with the receptacle 142. FIG. 6B presents yet a further enlarged
cross-sectional view of the plate 140 and the receptacle 142 of
FIG. 6A.
[0081] Referring again to FIG. 2, a locating and orienting assembly
160 is preferably provided for the end kit 110. In the arrangement
of FIG. 2, the locating feature is a guide pin 168. The locating
pin 168 is connected to the end kit 110. The locating pin 168 is
dimensioned to land into a pin receptacle 162 that is fabricated
into an item of subsea equipment.
[0082] In the arrangement of FIG. 2, the locating pin 168 is
connected to the upper housing 113. The pin 168 is disposed between
the junction plate 140 and the intermediate housing 112. However,
it is again understood that the precise location of the locating
assembly 160 is a matter of designer's choice. The present
invention only requires that, if employed, the locating assembly
160 enable location on subsea equipment through gravitational
urging.
[0083] FIGS. 7A-8D provide enlarged, cross-sectional views of the
locating assembly 160. These figures depict steps for landing the
locating pin 168 into the receptacle 162, and orienting the flying
lead 100. In FIG. 7A, the locating pin 168 is positioned vertically
over the receptacle 162, ready to be landed. It can be seen that
the pin 168 includes an upper plate 161. The upper plate 161
provides a body for a welding connection with the upper housing 113
and also serves as a stop member. The pin 168 also includes a
spherical body 163 at its lower end. The spherical end 163 permits
some degree, e.g., 10 degrees, of misalignment in the approach
angle.
[0084] The locating pin 168 includes an optional key 164. The key
164 is dimensioned to engage a corresponding shoulder 166 within
the receptacle 162. If the flying lead 100 is not properly oriented
as the pin 168 of the first end kit 110 is landed into the first
item of subsea equipment, the key 164 will force the flying lead
100 to reorient as the key 164 rides downward along the receptacle
shoulder 166. Ultimately, the key 164 will engage a slot 165 within
the receptacle 162 at the angle of proper orientation.
[0085] As can be seen, FIG. 7A is broken into two drawings, to
with, FIGS. 7A(1) and 7A(2). FIG. 7A(1) provides a side view of the
locating assembly 160, while FIG. 7A(2) provides a plan view. It is
to be understood that the pin 168/receptacle 162 arrangement of
FIGS. 7A(1) and 7A(2) is exemplary only, and that other
arrangements may be employed.
[0086] FIG. 7C-7G are provided to demonstrate the landing of the
pin 168 into the receptacle 162. The "(1)" series figures provide
progressive side views, while the "(2)" series figures provide
corresponding plan views. In FIGS. 7C(1)-(2), the locating pin 168
is being further lowered into the receptacle 162. The key 164 is
riding downward along the helical shoulder 166, providing proper
orientation for the flying lead (seen at 100 in FIG. 9A). In FIGS.
7F(1)-(2), the pin 168 has fully landed into the receptacle 162.
The key 164 has landed into a bottom slot 165 along the helical
shoulder. FIGS. 7F(1)-(2), provide the same step as FIGS.
7G(1)-(2), but at a different radial side view. It is noted that in
the embodiment shown in the FIG. 7 series, the receptacle 162 is
round, and includes a helically-shaped shoulder 166 for directing
the key 164. However, the present inventions are not limited by
this landing configuration. In this respect, the receptacle could
be a "Y"-shaped receptacle having a recess for receiving the fully
landed key 164.
[0087] Returning again to FIG. 2, it can be seen that the junction
plate 140 is disposed vertically over the receptacle 142 on an item
of subsea equipment (not shown). Likewise, the locating pin 168 is
disposed vertically over the receptacle 162 on the item of subsea
equipment. The tip 163 of the pin 168 is being received within an
upper conical opening 167 in the receptacle 162. The upper conical
opening 167 aides in placement of the locating pin 168.
[0088] Moving to FIG. 3, FIG. 3 demonstrates a next step in the
landing of the end kit 110 into an item of subsea equipment (not
shown). FIG. 3 provides a cross-sectional view of the flying lead
end kit 110 of FIG. 2. Here, the locating pin 168 has landed into
the receptacle 162. However, the MQC junction plate 140 has not yet
landed into the junction plate receptacle 142.
[0089] FIG. 4 presents a next step in the installation of the
flying lead end kit 110 of FIG. 2. In this view, the locating pin
168 has completely landed into the receptacle 162 on the item of
subsea equipment. In addition, the junction plate 140 has landed
into the junction plate receptacle 142 and is shown locked. The end
kit 110 is now ready to have fluid communication established
between the fluid communication line 115 and the item of subsea
equipment through actuation of an ROV (not seen).
[0090] FIG. 8 presents a flying lead end kit 110, in an alternate
embodiment. In this arrangement, a sheer pin 169 is utilized in the
locating pin 168. The shear pin 169 is employed as an optional
feature to aid in later retrieval of the flying lead 100. In this
respect, if the end kit 110 cannot be cleanly removed due to moment
that might be acting through the locating pin 168, the shear pin
will break, releasing the upper housing 113 from the locating
assembly 160.
[0091] It should also be noted that in FIG. 8, the swivel joint
116' between the upper housing 113 and the intermediate frame 116
can also be more clearly seen. A flex-limiter 170 is optionally
disposed at the end of the intermediate frame 112'. In this manner,
the rigidity of the end kit 110 is maintained, allowing the use of
steel-fabricated fluid lines 115. In the arrangement of FIG. 8, the
flex-limiter 170 defines a bushing inserted along an inner diameter
of the intermediate frame 116. However, other arrangements may be
provided. For example, adjusting the length or inner diameter of
the intermediate frame will affect the degree of swivel of the
intermediate housing 112.
[0092] FIGS. 9A-9C are provided to depict installation of an
embodiment of the flying lead 100 into a subsea production system.
Each of these figures presents a side view of a flying lead 100
being connected to items of subsea equipment on an ocean bottom 5.
Each end kit 110, 210 is being positioned over a respective
receptacle 162, 262. In this example, one receptacle 162 is
integrated into a subsea tree 940, while the second receptacle 262
is integrated into a SDU 950.
[0093] In FIG. 9A, the flying lead 100 is being lowered onto an
illustrative bed, such as the ocean bottom 5. The flying lead 100
is being connected to first and second items of subsea equipment,
shown at 940 and 950. The purpose is to place the first item of
subsea equipment 940, e.g., a subsea tree on a well 944, in fluid
communication with a second item of subsea equipment 950, e.g., a
SDU. As discussed above, dimensions for the end kits 110 and 210,
as well as the midsection 130, have been previously determined so
that the flying lead 100 may be prefabricated. Preferably, the
flying lead 100 is assembled prior to delivery onto a delivery
vessel. The flying lead 100 is dimensioned so that the junction
plate 140 on the first end kit 110 will land into a junction plate
receptacle 142 on the first item of subsea equipment 940, and the
junction plate 240 on the second end kit 210 will land into a
junction plate receptacle 242 on the second item of subsea
equipment 950. At the same time, the midsection 130 will
substantially rest along the ocean bottom 5. Because the first 110
and second 210 end kits are substantially or relatively rigid, the
communication lines connecting the subsea tree 940 and the SDU 950
can be of sufficient size to handle large amounts of chemicals or
other fluids. At the same time, the lines can be "thick walled" to
handle high pressure as required in some fields without affecting
installation.
[0094] As can be seen from FIG. 9A, the flying lead 100 is
configured to be lowered onto the ocean bottom 5 by means of a
spreader bar. A spreader bar is shown at 910. The spreader bar 910
defines a rigid and elongated tool having adjustable connectors 918
at opposing ends. In one arrangement, a chain 914 descends from
each of the opposing end connectors 918, and releasably attaches to
an end kit connector 117, 217 on the respective end kits 110, 210.
Releasable connections 912 are provided between the support wires
914 and the end kit connectors 117, 217. In this way, the flying
lead 100 can be landed on the equipment subsea. An example of an
end connector is a pad eye.
[0095] It can be seen that the spreader bar 910 is lowered into the
marine body by a collection of support wires. These wires may
include a central support line 917, lateral support wires 916 and a
hoisting line 915. A buoy 180 may optionally be integrated into the
spreader bar system. In the view of FIG. 9A, a buoy 180 is disposed
below the spreader bar 910, and is connected to the spreader bar
910 by a central buoy line 184. The central buoy line 184 extends
below the buoy through line 182, and connects to the midsection
130. In this manner, the central portion of the midsection 130 is
supported while the flying lead 100 is being lowered onto the ocean
bottom 5.
[0096] At the step in FIG. 9A, the locating pin 168 has been
positioned vertically over the receptacle 162. If the midsection
130 is not properly oriented to allow the second end kit 210 to
land on the SDU 950, then the key orienting arrangement 164/166
described above will provide proper orientation. In addition,
placement of the locating pin 168 into the receptacle 162 at proper
angular orientation provides that the junction plate 140 on the
first end 110 will properly latch into the junction plate
receptacle 142. An ROV (not shown) may be used to guide the pins
168, 268 into the respective receptacles 162, 262.
[0097] FIG. 9B shows the next step in the installation of the
flying lead 100. In FIG. 9B, the locating pin 168 has
gravitationally landed into the first receptacle 162. In addition,
the junction plate 140 has latched into the junction plate
receptacle 142. However, it can be seen that the second end kit 210
has not yet landed into the SDU 950. The midsection 130 remains
suspended above the ocean bottom 5.
[0098] Turning finally to FIG. 9C, the locating pin 268 in the
second end kit 210 has landed into the second receptacle 262.
Likewise, the junction plate 240 has latched into the junction
plate receptacle 242. Thus, the flying lead 100 has been
mechanically installed into the subsea production system. The
midsection 130 may now rest on the ocean bottom 5.
[0099] It should be noted that merely because the flying lead 100
has been gravitationally landed into a subsea production system 10
does not mean that fluid communication has been established between
first 940 and second 950 items of subsea equipment. In the
preferred embodiment, an ROV is utilized to actuate the junction
plates 140, 240. Actuation of the junction plates 140, 240 provides
fluid communication between the items of subsea equipment 940, 950
and the intermediate flow lines 115, 215, 135. An ROV can be seen
above the SDU 950 at 930 in FIG. 9C.
[0100] Finally, FIG. 10 is provided in order to show a top view of
the flying lead being landed into a subsea tree 940 and a SDU 950.
In this view, opposing end kits 110, 120 are seen. In addition, the
spreader bar 910 is visible. The underlying midsection 130 is
hidden by the spreader bar 910.
[0101] In addition to the flying lead 100 disclosed herein, a
method for installing a flying lead is also provided. The flying
lead is configured to provide fluid communication between a first
item of subsea equipment and a second item of subsea equipment in a
marine body. The flying lead is placed onto a vessel, and the
vessel is located generally above the first and second items of
subsea equipment. The flying lead would be as described in the
embodiments above, and as claimed below.
[0102] The flying lead is secured to a spreader bar. The spreader
bar with connected flying lead is then lowered from the vessel and
downward into the marine body towards the subsea bottom. The first
end kit to the flying lead is positioned above the first item of
subsea equipment. Likewise, the second end kit is positioned above
the second item of subsea equipment. Positioning may be done with a
launched ROV.
[0103] The first end kit is landed into the first item of subsea
equipment. More specifically, the junction plate on the first end
kit is landed into a junction place receptacle on the first item of
subsea equipment. Use of a locating and orienting assembly such as
the one described above may be optionally employed.
[0104] The junction plate on the second end kit is positioned over
a junction plate receptacle on the second item of subsea equipment.
The junction plate on the second end kit is then gravitationally
landed into the junction plate receptacle for the second item of
subsea equipment. At that point, mechanical landing of the flying
lead between first and second items of subsea equipment has been
accomplished.
[0105] In one embodiment, the mechanical landing of the flying lead
onto opposing items of subsea equipment also establishes fluid
communication between the first and second items of subsea
equipment. However, it is preferred that separate steps be taken to
actuate fluid communication between fluid communication lines of
the first end kit and the first item of subsea equipment, and
between fluid communication lines of the second end kit and the
second item of subsea equipment. These actuation steps may also be
accomplished through use of an ROV as is known in the art.
[0106] In one arrangement, the present rigid flying lead reduces
leaks due to the all-welded construction. Because the present SFL
is rigid, the encased lines can be larger to handle increased
amounts of chemicals required in some fields. The lines can also be
"thick walled" to withstand high collapse pressures encountered in
some fields without affecting installation. The rigid steel casing
provides protection to the steel tubes at all times during offshore
handling and installation. It also provides protection to the
couplers at all times, including the landing operation.
[0107] A description of certain embodiments of the inventions has
been presented above. However, the scope of the inventions is
defined by the claims that follow. Each of the appended claims
defines a separate invention, which for infringement purposes is
recognized as including equivalents to the various elements or
limitations specified in the claims.
* * * * *