U.S. patent application number 14/355752 was filed with the patent office on 2014-10-30 for fluid transfer hose manipulator and method of transferring a fluid.
The applicant listed for this patent is SHELL INTERNTIONALE RESEARCH MAATSCHAPPIJ B.V.. Invention is credited to Andrew Michael Alderson, Gianpaolo Benedetti.
Application Number | 20140318666 14/355752 |
Document ID | / |
Family ID | 47088898 |
Filed Date | 2014-10-30 |
United States Patent
Application |
20140318666 |
Kind Code |
A1 |
Benedetti; Gianpaolo ; et
al. |
October 30, 2014 |
FLUID TRANSFER HOSE MANIPULATOR AND METHOD OF TRANSFERRING A
FLUID
Abstract
A fluid transfer hose manipulator is presented having an
articulated arm having a plurality of arm sections. A first arm
section of the plurality of arm sections and a second arm section
of the plurality of arm sections are connected to each other by a
first pivot joint. A base supports the first arm section. At least
one flexible hose for fluid transfer extends movably along at least
the first and second arm sections, and is directed and supported by
at least two hose guides. At least one hose tensioner is in contact
with the flexible hose to adjust the tension on the at least one
flexible hose.
Inventors: |
Benedetti; Gianpaolo;
(London, GB) ; Alderson; Andrew Michael; (London,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SHELL INTERNTIONALE RESEARCH MAATSCHAPPIJ B.V. |
The Hague |
|
NL |
|
|
Family ID: |
47088898 |
Appl. No.: |
14/355752 |
Filed: |
November 1, 2012 |
PCT Filed: |
November 1, 2012 |
PCT NO: |
PCT/EP2012/071664 |
371 Date: |
May 1, 2014 |
Current U.S.
Class: |
141/1 ;
414/139.6 |
Current CPC
Class: |
B65B 3/04 20130101; B63B
27/24 20130101 |
Class at
Publication: |
141/1 ;
414/139.6 |
International
Class: |
B63B 27/24 20060101
B63B027/24; B65B 3/04 20060101 B65B003/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 11, 2011 |
EP |
11187600.9 |
Claims
1. A fluid transfer hose manipulator, said hose manipulator
comprising at least: an articulated arm comprising a plurality of
arm sections, each arm section having a longitudinal axis, said
plurality of arm sections comprising at least a first arm section
and a second arm section, said first arm section connected to said
second arm section by a first pivot joint; a base supporting said
first arm section; at least two hose guides; at least one flexible
hose for fluid transfer, said flexible hose extending movably along
at least said first and second arm sections and directed and
supported by said at least two hose guides; at least one hose
tensioner in contact with the flexible hose to adjust the tension
on the at least one flexible hose.
2. The hose manipulator of claim 1, wherein said hose tensioner is
supported off of one of said arm sections or supported on said
base.
3. The hose manipulator of claim 1, wherein the hose tensioner
comprises a tensioner hose guide to direct the at least one
flexible hose along a path being deflected from a nominal path by
an amount, wherein said tensioner hose guide is movable in a
direction having a transverse directional component relative to the
nominal path, whereby the amount of deflection of the flexible hose
from the nominal path is variable.
4. The hose manipulator of claim 1, wherein the at least one hose
tensioner is connected to the base.
5. The hose manipulator of claim 1, wherein the at least one hose
tensioner is connected to the second arm section.
6. The hose manipulator of claim 1, wherein one or more of the hose
guides are sheaves.
7. The hose manipulator of claim 1, further comprising a third arm
section and a further hose guide, said third arm section connected
to said second arm section by a second pivot joint and having the
further hose guide positioned thereon, said flexible hose extending
movably along the longitudinal axis of the third arm section.
8. The hose manipulator claim 1, wherein said at least one flexible
hose further comprises a proximal end and a distal end, said
proximal end in fluid communication with a fluid first storage tank
and wherein said distal end comprises a restriction cone and a
fluid connector.
9. The hose manipulator of claim 8, wherein the distal end further
comprises an emergency release coupling.
10. The hose manipulator of claim 8, further comprising a position
monitoring system to monitor a position of the distal end of the
flexible hose relative to a reference position on one of the arm
sections.
11. The hose manipulator of claim 10, wherein the position
monitoring system comprises a positioning sensor connected to the
end of one of the arm sections to measure the position of the
distal end of the flexible hose.
12. The hose manipulator of claim 1, comprising two flexible hoses
for fluid transfer, each said flexible hose having dedicated hose
guides and tensioner.
13. The hose manipulator of claim 1, wherein the fluid is a
cryogenic fluid, for instance LNG.
14. A method of transferring a fluid between first and second
structures, wherein at least one of the first and second structures
is a moveable structure, typically a floating structure, comprising
at least the steps of: providing a first structure comprising a
fluid transfer hose manipulator according to claim 1, the at least
one flexible hose of the fluid transfer hose manipulator having a
proximal end connected to a fluid first manifold and having a
distal end; providing a second structure comprising a fluid second
manifold; aligning the fluid second manifold of the second
structure with the fluid transfer hose manipulator of the first
structure; adjusting the configuration of the fluid transfer hose
manipulator so that the distal end of the at least one flexible
hose can be connected to the fluid second manifold; connecting the
distal end of the at least one flexible hose to the fluid second
manifold; purging the at least one flexible hose; passing a fluid
through the at least one flexible hose; purging the at least one
flexible hose; disconnecting the distal end of the at least one
flexible hose from the fluid second manifold; adjusting the
configuration of the fluid transfer hose manipulator to withdraw
the distal end of the at least one flexible hose from the fluid
second manifold and second structure.
15. The method of claim 14, wherein the fluid first manifold is in
fluid connection with at least one fluid first storage tank and the
fluid second manifold is in fluid connection with at least one
fluid second storage tank.
Description
[0001] The present invention relates to a fluid transfer hose
manipulator. In an other aspect, the present invention relates to a
method of transferring a fluid between first and second
structures.
[0002] The transfer of fluids, such as processed or unprocessed
hydrocarbons or their derivatives, between structures, when at
least one of the structures is moveable and may therefore not be
stationary, poses a number of technical problems. This is
particularly the case when at least one or both of the structures
is a floating structure. For instance, such a fluid transfer system
should be capable of mitigating against a relative motion between
the structures, particularly in terms of one or more of the heave,
yaw, sway, pitch, surge and roll experienced by a floating
structure.
[0003] In particular, a system for fluid transfer from or to a
floating structure should compensate for heave produced by wave
motion or tidal motion, as well as for height differences between
the source and destination. Such height differences may arise, for
instance, due to the differences in the vertical position of the
fluid transfer system on one structure relative to the fluid
manifold on another structure to which the transfer system is to be
connected. One example of where such a fluid transfer system would
be required is in a floating production, storage and offloading
(FPSO) facility. A FPSO is a floating structure which receives
hydrocarbon from nearby platforms or directly from a subsea
hydrocarbon reservoir, processes the hydrocarbon and stores the
processed hydrocarbon until it can be offloaded onto a carrier
vessel.
[0004] Similarly, a Floating Liquefaction Storage Off-shore (FLSO)
facility combines the natural gas liquefaction process, storage
tanks, loading systems and other infrastructure into a single
floating structure. Such a structure is advantageous because it
provides an off-shore alternative to on-shore liquefaction plants.
An FLSO structure can be moored off the coast, or close to or at a
gas field, in waters deep enough to allow off-loading of the LNG
product onto a carrier vessel. It also represents a movable asset,
which can be relocated to a new site when the gas field is nearing
the end of its productive life, or when required by economic,
environmental or political conditions.
[0005] Such floating structures require the transfer of fluids,
typically processed hydrocarbons such as LNG, between the floating
structure on which the hydrocarbon is processed e.g. where natural
gas is optionally purified, then liquefied and temporarily stored,
to the processed hydrocarbon carrier vessel e.g. an LNG carrier
vessel. Similarly, the processed hydrocarbon cargo, such as LNG,
must then be transferred from the carrier vessel to an on-shore
import or processing facility.
[0006] US Patent Publication No. US 2010/0263389 discloses methods
for the dockside regasification of LNG. In one embodiment disclosed
in FIG. 2, a high pressure arm to transfer high pressure gas is
mounted on a dock or regasification vessel. An LNG hard arm similar
to the high pressure arm to transfer LNG from a ship-to-dock or a
dock-to-ship is also disclosed. The arm comprises transfer piping
and may contain multiple joints, a dampener and counterweights to
allow movement or articulation of arm sections. One problem
associated with the hard arm of US 2010/0263389 is that it has a
limited vertical range i.e. the range of height which the end of
the hard arm can reach, when connecting to a fluid manifold. In
addition, the hard arm and the base, such as a deck, to which it is
connected must be designed to bear the weight of the hard arm,
including the counterweights and damper. Furthermore, the large
mass of the upper arm section also increases the inertia of the arm
movement, making it more difficult to control the arm movement in
response to wind and wave motion.
[0007] In a separate embodiment, US 2010/0263389 discloses in FIG.
8 the transfer of LNG from a storage tank on an LNG carrier through
a manifold system having liquid conduits coupled to liquid hoses.
Although the deck can support a portion of the liquid hoses, it is
apparent from the Figure that these hang in a U-shape over the
water separating the two fluid manifolds. One problem associated
with the manifold and hose system of US 2010/0263389 is that liquid
may accumulate in the lowest section of the U-shape hose and it is
difficult to drain such liquid after fluid transfer. In addition,
the free-hanging liquid hoses are uncontrolled, which can lead to
impact between adjacent hoses or between a hose and the side of the
vessel as a result of relative movement between the manifolds.
[0008] In a first aspect, the present invention provides a fluid
transfer hose manipulator, said hose manipulator comprising at
least: [0009] an articulated arm comprising a plurality of arm
sections, each arm section having a longitudinal axis, said
plurality of arm sections comprising at least a first arm section
and a second arm section, said first arm section connected to said
second arm section by a first pivot joint; [0010] a base supporting
said first arm section; [0011] at least two hose guides; [0012] at
least one flexible hose for fluid transfer, said flexible hose
extending movably along at least said first and second arm sections
and directed and supported by said at least two hose guides; [0013]
at least one hose tensioner in contact with the flexible hose to
adjust the tension on the at least one flexible hose.
[0014] In a second aspect, a method of transferring a fluid between
first and second structures, wherein at least one of the first and
second structures is a moveable structure, preferably a floating
structure, is provided, said method comprising at least the steps
of: [0015] providing a first structure comprising a fluid transfer
hose manipulator as described herein, the at least one flexible
hose of the fluid transfer hose manipulator having a proximal end
connected to a fluid first manifold and having a distal end; [0016]
providing a second structure comprising a fluid second manifold;
[0017] aligning the fluid second manifold of the second structure
with the fluid transfer hose manipulator of the first structure;
[0018] adjusting the configuration of the fluid transfer hose
manipulator so that the distal end of the at least one flexible
hose can be connected to the fluid second manifold; [0019]
connecting the distal end of the at least one flexible hose to the
fluid second manifold; [0020] purging the at least one flexible
hose; [0021] passing a fluid through the at least one flexible
hose; [0022] purging the at least one flexible hose; [0023]
disconnecting the distal end of the at least one flexible hose from
the fluid second manifold; [0024] adjusting the configuration of
the fluid transfer hose manipulator to withdraw the distal end of
the at least one flexible hose from the fluid second manifold and
second structure.
[0025] In one embodiment of the second aspect, the fluid first
manifold can be in fluid connection with at least one fluid first
storage tank and the fluid second manifold can be in fluid
connection with at least one fluid second storage tank.
[0026] Embodiments of the present invention will now be described
by way of example only and with reference to the accompanying
non-limited drawings in which:
[0027] FIG. 1 is a diagrammatic scheme of one embodiment of a fluid
transfer hose manipulator described herein;
[0028] FIG. 2 is a diagrammatic scheme of another embodiment of a
fluid transfer hose manipulator described herein;
[0029] FIG. 3 is a diagrammatic scheme of a further embodiment of a
fluid transfer hose manipulator described herein; and
[0030] FIG. 4 (parts A to C) diagrammatically shows various storage
and fluid transfer configurations of a fluid transfer hose
manipulator described herein.
[0031] For the purpose of this description, a single reference
number will be assigned to a line as well as a stream carried in
that line. Same reference numbers refer to similar components. The
person skilled in the art will readily understand that, while the
invention is illustrated making reference to one or more a specific
combinations of features and measures, many of those features and
measures are functionally independent from other features and
measures such that they can be equally or similarly applied
independently in other embodiments or combinations.
[0032] The fluid transfer hose manipulator described below is
suitably employably particularly for the transfer of fluids to or
from a floating structure, especially in the marine environment.
The fluid transfer hose manipulator is particularly suitable for
the transfer of cryogenic fluids, especially liquefied natural gas
(LNG). A method of fluid transfer using such a hose manipulator is
also disclosed.
[0033] The presently proposed fluid transfer hose manipulator has
an articulated arm comprising a plurality of arm sections
interconnected by pivot joints and at least one flexible hose for
fluid transfer. The flexible hose extends movably along arm
sections and is directed and supported by at least two hose guides.
At least one hose tensioner is provided in contact with the
flexible hose to adjust the tension on the at least one flexible
hose.
[0034] The hose tensioner may operate to maintain a constant
tension on the flexible hose. Maintaining constant tension can
prevent the flexible hose from sagging or breaking (or at least
prevent the flexible hose from becoming over tensed) during
transferring of a fluid through the flexible hose.
[0035] With the presently disclosed fluid transfer hose manipulator
it is possible to replace the hard arm or manifold system of the
prior art and therewith to address various problems associated with
the hard arm or manifold system of the prior art.
[0036] A first of said arm sections may be supported on a base. The
tensioner may be supported by one of said arm sections or directly
by said base.
[0037] As examples, the fluid transfer hose manipulator may be
located on a floating structure, such as a carrier vessel, a
floating production platform or a floating processing platform and
operate to transfer fluid to another floating structure or a
non-floating structure. Alternatively, the fluid transfer system
may be located on a non-floating structure, such as a fixed
production or processing platform or on-shore, such as on a jetty
of an import or export terminal or of a processing facility, and
operate to transfer fluid to or from a floating structure, such as
a carrier vessel.
[0038] The fluid to be transferred by the hose manipulator may be
an unprocessed hydrocarbon e.g. one extracted from an undersea
reservoir, or a processed hydrocarbon, such as LNG or a hydrocarbon
derivative.
[0039] The hose manipulator described herein has a number of
advantages. It can transfer fluid from or to a fluid manifold for
supplying or receiving a fluid located at a wide range of heights
relative to the base to which the hose manipulator is attached. In
particular, the hose manipulator described herein has a much wider
vertical range of operation compared to the hard arm of US
2010/0263389. In addition, it does not require the presence of a
counterweight such that the articulated arm and the base to which
it is attached need only support the load of the arm sections and
flexible hose. Furthermore, the hose manipulator may be located on
a manifold platform, which due to the reduced mass of the hose
manipulator compared to a counterweighted hard arm, does not need
to be reinforced to bear the weight.
[0040] In addition, in contrast to the dampener of US 2010/0263389,
which is attached to and operates on the entire upper articulated
section of the hard arm, the tensioner of the hose manipulator
disclosed herein operates directly on the flexible hose, and not on
an arm section.
[0041] Also, by utilising flexible hose rather than rigid piping,
there is no need to provide swivel joints connecting the pipes in
different sections of the articulated arm.
[0042] The hose manipulator is also advantageous because it
maintains the flexible hose in a substantially vertical or a
"n-shaped" configuration, eliminating fluid retention. In contrast,
flexible hoses which are not supported in this way, such as in the
manifold and hose system of US 2010/0263389, can adopt a "u-shaped"
configuration in which fluid can accumulate at the base of the
"u".
[0043] In one embodiment, one of said at least two hose guides may
be located at or near an end of the longitudinal axis of each arm
section. As used herein, the longitudinal axis is the longest
dimension of the arm section.
[0044] In another embodiment, the at least one flexible hose may
further comprise a proximal end and a distal end.
[0045] The proximal end may be connected to the base. The proximal
end may be configured in fluid communication with a fluid first
storage tank. Said distal end may suitably comprise a restriction
cone and a fluid connector. For instance, the proximal end may be
connected to a fluid first manifold which is in fluid communication
with a fluid first storage tank, typically a plurality of fluid
first storage tanks. The fluid first storage tank preferably has a
fixed position relative to the base.
[0046] In another embodiment, the hose tensioner maintains the at
least one flexible hose under constant tension. The tension under
which the at least one flexible hose is maintained may change and
can be selected depending upon one or more of the following
criteria: whether the distal end of the flexible hose is attached
to a fluid manifold, the relative distance between the hose
manipulator and a fluid manifold to which it is attached,
particularly the vertical distance between the base of the hose
manipulator and the fluid manifold to which it is attached, whether
fluid is being transferred through the at least one flexible hose
and/or the characteristics of any fluid being transferred, such as
the fluid temperature or density.
[0047] In one embodiment, the at least one hose tensioner may be
connected to the base of the hose manipulator. The base may be, for
instance, a deck of a carrier vessel or PFSP, particularly the
manifold deck, or the surface of a jetty. This is advantageous
because it provides a stable arrangement of the hose connector, in
which the hose tensioner is attached to the base rather than one of
the arm sections.
[0048] In alternative embodiments, the at least one hose tensioner
may be connected to an arm section of the hose manipulator,
particularly an arm section other than the first arm section,
preferably the second or any third arm section. Supporting the at
least one hose tensioner off of one or the arm segments, preferably
the second or any third arm segment, is advantageous because it can
provide a greater deflection of the flexible hose from the
longitudinal axis of the arm section to which the hose tensioner is
connected, thereby facilitating a larger operating envelope, in
terms of the relative positions of the hose manipulator and the
manifold to which the flexible hose can be attached.
[0049] In a further embodiment, the hose tensioner may comprise a
tensioner hose guide to direct and optionally support the at least
one flexible hose. Such tensioner hose guide may direct the at
least one flexible hose along a path that is deflected from a
nominal path. The nominal path may be any suitable reference path
depending on the circumstances of the specific embodiment. For
instance, if the tensioner hose guide interacts with the flexible
hose in a section of the flexible hose that extends between two
adjacent hose guides, the nominal path may be defined by the line
that tangentially connects the two adjacent hose guides.
Alternatively, if for instance the tensioner hose guide interacts
with the flexible hose in a section of the flexible hose that
extends between the proximal end and the first hose guide of the
hose guides, the nominal path may be defined by or by the line that
tangentially connects the first hose guide with the proximal end of
the flexible hose. The proximal end may be connected in a fixed
point relative to the base.
[0050] The tensioner hose guide may be movable in a direction
having a transverse directional component relative to the nominal
path. Herewith the amount of deflection of the hose from the
nominal path can be variably changed.
[0051] The hose tensioner may suitably be connected to one of said
arm sections, wherein the tensioner hose guide can move along a
path at a non-zero path angle .alpha. to the longitudinal axis of
the arm section to which it is connected, thereby changing the
amount of deflection of the hose from its nominal path.
[0052] In a yet another embodiment, when the hose tensioner is
connected to one of the arm sections, the deflection of the path of
the hose by the movement of the tensioner hose guide may occur on
either side of the longitudinal axis of the arm section to which
the tensioner is connected. The longitudinal axes of two connected
arm sections can define an arm section angle .beta. at the pivot
joint connecting them. When the arm section angle .beta. is other
than 180.degree., the longitudinal axes of the two connected arm
sections can define an arm pivoting plane which passes through both
longitudinal axes. The non-zero path angle .alpha. may be a
positive or a negative angle measured with respect to the
longitudinal axis of the arm section to which the hose tensioner is
connected in the arm pivoting plane or a plane parallel
thereto.
[0053] The hose guides for a particular flexible hose may be
positioned parallel to the arm pivoting plane. For instance, when a
plurality of flexible hoses are present on a hose manipulator,
equivalent hose guides for different flexible hoses may be arranged
symmetrically about to the arm pivoting plane.
[0054] In a further embodiment, the hose tensioner may be connected
at or near the centre of the longitudinal axis of said arm section
and the path which the tensioner hose guide can move along is at an
angle .alpha. of approximately 90.degree. to the longitudinal axis
of the arm section to which it is connected.
[0055] In a still further embodiment, the tensioner hose guide can
be moved by one or more of the group comprising a tensioner
cylinder, electric motor and wire sheave.
[0056] In a further embodiment, one or more, preferably all, of the
hose guides may be sheaves. This embodiment may include the
tensioner hose guide, as well as the hose guides connected to the
arm sections which do not form part of the hose tensioner.
[0057] The first arm section is suitably connected to a second arm
section by a first pivot joint. In another embodiment, the hose
manipulator may further comprise a third arm section and a further
hose guide, wherein the third arm section is connected to said
second arm section by a second pivot joint and the third arm
section has the further hose guide positioned thereon. The flexible
hose can extend movably along the longitudinal axis of the third
arm section. The second pivot joint may be connected to the second
arm at the opposite end of the longitudinal axis to the end which
is connected to the first pivot joint.
[0058] In another embodiment, the distal end of the at least one
flexible hose may comprise an emergency release coupling,
optionally in addition to the restriction cone and fluid connector.
The emergency release coupling is configured to quickly separate
the at least one flexible hose, and particularly the distal end,
from a fluid manifold to which it is connected, for instance if
conditions arose in which the hose manipulator extended beyond its
safe operating envelope while connected to a fluid manifold during
fluid transfer.
[0059] In a further embodiment, the hose manipulator may further
comprise a position monitoring system to monitor the position of
the distal end of the flexible hose. The position of the distal end
may be monitored as an absolute position, i.e. with regard to the
location of the distal end on the earth, or in relative terms, for
instance the position of the distal end may be monitored with
respect to a relative position on the hose manipulator, such as a
relative position on an arm section or the base.
[0060] In a yet further embodiment, the position monitoring system
may comprise a positioning sensor to measure the position of the
distal end of the flexible hose. For instance, the positioning
sensor may be connected to the end of an arm section, preferably a
second or third arm section. The positioning sensor may operate by
laser, radar, lidar, echolocation or taught wire etc. For example,
a taught wire sensing system may comprise a wire connected between
the distal end of the flexible hose, such as a restriction cone
located on the distal end, or a tie bar on the distal end, and a
gimbal head affixed to the second or any third arm section. A
gimbal head sensor, such as a laser, can measure the angle of the
gimbal head to calculate the position of the distal end from the
angle and the length of the taught wire.
[0061] In an alternative embodiment, the distal end of the at least
one flexible hose may further comprise a position referencing
sensor, particularly a vertical position referencing sensor such as
GPS or the like. In this case, it is not necessary to determine the
position of the distal end of the flexible hose with respect to a
position on the hose manipulator. Instead, the absolute position of
the distal end of the at least one flexible hose may be
determined.
[0062] In a further embodiment, the hose manipulator may comprise
at least two flexible hoses for fluid transfer, typically two
flexible hoses, with each of the flexible hoses having hose guides
and a hose tensioner. Preferably, the flexible hoses are arranged
in planes located symmetrically on either side of the arm pivoting
plane. Providing hose guides, and more significantly a hose
tensioner, dedicated to a specific flexible hose, allows each
flexible hose to be manipulated independently, particularly with
regard to the tension of each flexible hose controlled by each hose
tensioner. Thus the magnitude of the path deflection of a specific
flexible hose produced by the hose tensioner can be controlled
independently of any other hoses on the hose manipulator. It will
be apparent that different flexible hoses may carry different
fluids, which may have different characteristics, such as densities
and/or temperatures, for instance when one flexible hose is
carrying LNG and another flexible hose is carrying boil off gas,
such that the deflection of the paths of two flexible hoses, even
on the same hose manipulator, may be required to be different e.g.
in order to provide a given tension.
[0063] In another embodiment, the fluid to be transferred in the
hose manipulator may be a cryogenic fluid, such as LNG.
[0064] In a further embodiment, the hose manipulator may further
comprise a storage spool for the flexible hose. The storage spool
allows the length of the flexible hose connecting to a manifold for
fluid to be adjusted. However, this embodiment is not preferred.
Instead, the hose manipulator would not typically comprise a
storage spool for the flexible hose, such that the extent to which
a flexible hose of fixed length extends beyond an end of the final
arm section, e.g. a second or third arm section, is determined only
by the magnitude of the deflection of the path of the flexible hose
by the hose tensioner.
[0065] In a still further embodiment, the arm sections of the hose
manipulator may be articulated at a pivot joint by one or more
hydraulic cylinders, electric motors or wire sheaves.
[0066] The following discussion relates to the operation of a fluid
transfer hose manipulator in the context of the transfer of LNG
from an FLSO unit to an LNG carrier vessel. However, it should be
understood that the hose manipulator is not limited to the transfer
of LNG, but is suitable for the transfer of any fluid or fluids,
such as other hydrocarbon liquids or hydrocarbon gases, over a wide
range of temperatures and pressures, typically temperatures in the
range of -200 to 200 .degree. C. and/or pressures up to 10.5
bar.
[0067] Similarly, although the hose manipulator is located on a
FPSO unit in the following embodiments, it can operate on any
floating structure, such as an LNG carrier vessel or on any
non-floating structure, such as an off-shore fixed platform or an
on-shore jetty. Although many of the advantages of the hose
manipulator arise when it is used to transfer fluid when at least
one, typically both, of the fluid source and fluid destination are
moveable structures, particularly floating structures, it can also
be used for fluid transfer between two non-floating structures.
[0068] FIG. 1 shows a first embodiment of the fluid transfer hose
manipulator 1 described herein. The hose manipulator comprises an
articulated arm 100 fixed to a base 220. The articulated arm 100
comprises a plurality of arm sections 110. The base 220 may be, for
instance, the manifold deck of an FLSO or attached to such a deck.
The base 220 may function as the reference point from which the
position of the arm sections 110 and at least one flexible hose
150, particularly a distal end 180 of a flexible hose 150, can be
determined. The hose manipulator 1 may be located outboard of the
fluid (e.g. LNG) manifold.
[0069] Each arm section 110 has a longitudinal axis 120, defining
the longest dimension of the arm section. The embodiment of FIG. 1
shows an articulated arm 100 comprising first arm section 110a and
second arm section 110b. The first arm section 110a has a first
section longitudinal axis 120a, and the second arm section 110b has
a second section longitudinal axis 120b.
[0070] The base 220 supports the first arm section 110a. The first
arm section 110a is connected to base 220 and is preferably fixed
immovably to the base 220, with its longitudinal axis 120a
vertical. The first arm section 110a is connected to the second arm
section 110b by a first pivot joint 130a, such as a hinge or any
type of joint allowing for a relative rotational movement of the
first arm section relative to the second arm section. The first
pivot joint 130a allows rotation of the second arm section 110b
about a first joint axis 135a. The rotation of the second arm
section 110b can be in a plane (the arm pivoting plane) defined by
the first and second longitudinal axes 120a, 120b.
[0071] The articulation of the second arm section 110b may be
achieved by a hydraulic cylinder (not shown) or other suitable
means. The hydraulic cylinder may be part of a hydraulic system and
can be connected to a hydraulic power unit with associated
directional valves and pumps. This is preferably a duplex system
with duplicate hydraulic pumps and associated controls. In a
further preferred embodiment, the hydraulic system may be fitted
with hose burst valves so that the arm sections can remain in
position it the event of a failure of the hydraulic system. The
hydraulic system may comprise a low pressure circulation circuit
for normal operation and a high pressure circuit for activation of
the emergency release, which is discussed below.
[0072] The fluid transfer hose manipulator 1 further comprises at
least one flexible hose 150. The type of flexible hose 150 will be
determined by the fluid to be carried within it. The flexible hose
150 should be selected to retain its flexibility during fluid
transfer i.e. the temperature and pressure and pressure of the
fluid being transferred. The flexible hose 150 may comprise a
thermoplastic or composite material.
[0073] For instance, when the fluid to be transferred is a
cryogenic fluid such as LNG, the flexible hose 150 may be a
composite flexible hose, typically comprising a polyester lining
with a polyamide outer cover reinforced with stainless steel wire.
Typically, the flexible hose 150 may be selected to meet the
requirements of BS EN 13766:2003 for thermoplastic multi-layer
(non-vulcanised) hoses and hose assemblies for the transfer of
liquid petroleum gas and liquefied natural gas.
[0074] When the fluid to be transferred is a gas, such as a
pressurised hydrocarbon gas, the flexible hose 150 may be a
composite flexible hose. For instance, for working pressures up to
5 bar, the flexible hose may typically comprise a polypropylene
and/or polytetrafluoroethylene lining with a polyester outer cover,
optionally coated with polyvinyl chloride, and reinforced with
stainless steel wire.
[0075] The at least one flexible hose 150 may comprise a proximal
end 170 and a distal end 180. The proximal end 170 may be connected
to a fluid first manifold 310, which can be situated on the
manifold deck of the FLSO. The at least one flexible hose is has a
length of approximately 30 m. In a preferred embodiment the
flexible hose 150 is not wound around an storage spool.
[0076] The fluid first manifold 310 may comprise a fluid manifold
restriction collar 320. The fluid manifold restriction collar 320
may be configured as an open cone and operates to prevent the
flexible hose 150 from adopting a configuration with a bending
radius less than its minimum. The distal end 180 of the flexible
hose 150 is configured to be attached to a fluid second manifold,
for instance on an LNG carrier vessel to which the LNG fluid is to
be transferred. The distal end 180 of the flexible hose 150 is
discussed in more detail in the embodiment of FIG. 3.
[0077] The at least one flexible hose 150 extends movably along
first and second arm sections 110a, 110b of the articulated arm
100. In particular, when not deflected by the hose tensioner 160
that will be discussed below, the flexible hose should extend along
the longitudinal axis (or an axis parallel to this) of the arm
sections 110a, 110b.
[0078] The flexible hose 150 is directed and supported by at least
two hose guides 140. The hose guides 140 allow free movement of the
flexible hose 150 along the guides, and transfer the weight of the
flexible hose 150 and any fluid therein to the hose manipulator 1,
and specifically the arm sections 110 to which they can be
attached. The hose guides 140 can act to change the direction of
the flexible hose 150 and ensure that the any bending of the hose
is greater than or equal to its minimum bending radius.
[0079] When the proximal end 170 of the flexible hose 150 is fixed
to fluid first manifold 310, and the flexible hose 150 is of a
fixed length, rotation of second arm section 110b about the first
pivot joint 130a can control the vertical height of distal end 180
with respect to the base 220 of the hose manipulator 1.
[0080] The embodiment of FIG. 1 shows arcuate hose guides 140 over
which the flexible hose 150 is directed. The flexible hose 150 may
run along grooves or channels on such hose guides 140. The grooves
or channels on each hose guide 140 can be aligned in the same
plane, such as a plane parallel to the arm pivoting plane, in order
to direct a single flexible hose 150 along a route in a single
plane. The hose guides 140 may be made of a polymer, metal, such as
aluminium, alloy, such as steel, typically nickel steel, or
composite, such as a composite comprising polymer, particularly a
composite comprising polymer and metal or alloy such as those
already mentioned. When the flexible hose 150 is to carry a
cryogenic fluid, the hose guides 140 may comprise 9 wt % nickel
steel. The hose guide 140 may comprise a material which reduces the
frictional contact with the flexible hose 150, thereby allowing
freedom of movement. For instance, the grooves or channels on the
hose guides 140 may be lined with TEFLON.TM..
[0081] The at least two hose guides 140 may be fixed to the
articulated arm 100. FIG. 1 shows first hose guide 140a fixed to
first arm section 110a, and second hose guide 140b fixed to second
arm section 110b. Preferably, the hose guide 140 is attached at or
near to an end of an arm section 110, the ends lying at either end
of longitudinal axis 120 of an arm section 110.
[0082] The articulated arm 100 further comprises at least one hose
tensioner 160. The hose tensioner 160 operates to adjust the
tension on the at least one flexible hose 150 and is thus in
contact with the flexible hose 150. The hose tensioner 160 is
connected to one of the arm sections 110 or the base 220 of the
hose manipulator 1. The hose tensioner 160 operates to maintain a
constant tension on flexible hose 150, particularly when both
proximal and distal ends 170, 180 are connected to fluid
manifolds.
[0083] In the embodiment of FIG. 1, the hose tensioner 160
comprises a tensioner hose guide 165, such as an arcuate tensioner
hose guide, and a tensioner arm 175, e.g. a telescopic tensioner
arm, to direct the flexible hose 150 along a path that is deflected
from a nominal path 155.
[0084] In the embodiment of FIG. 1, the nominal path 155 is taken
to be the line that tangentially connects the first hose guide 140a
with the proximal end 170 of the flexible hose 150. The tensioner
hose guide 165 is movable in a direction having a transverse
directional component relative to the nominal path 155. Movement in
such a direction allows to variably change the degree of deflection
of the hose from the nominal path 155.
[0085] The tensioner hose guide 165 can be connected to one of the
arm sections 110 of the articulated arm 100, such as the first arm
section 110a, via the tensioner arm 175. Although the hose
tensioner 160 is shown as being attached to the first arm section
110a in FIG. 1 for simplicity, it is preferred that it is attached
to a second or further arm section 110b in order to provide a
greater range of movement, by distancing it from base 220 and any
adjacent deck.
[0086] The tensioner hose guide 165 functions to restrain and guide
flexible hose 150 to ensure that the any bending of the hose is
greater than or equal to its minimum bending radius, in a similar
manner to the hose guides 140.
[0087] Furthermore, the tensioner hose guide 165 can move along a
path at a non-zero path angle .alpha., measured from the
longitudinal axis of the arm section to which it is attached. When
both proximal and distal ends 170, 180 of the flexible hose 150 are
connected to fluid manifolds, moving the tensioner hose guide 165
along non-zero path angle .alpha. will change the deflection of the
hose, thereby changing the tension of the hose. The non-zero path
angle .alpha., measured with respect to the longitudinal axis 120a
of the first arm section 110a to which the hose tensioner 160 is
connected, is typically approximately 90.degree., more typically
90.degree.. The movement of the tensioner hose guide 165 can be
achieved by increasing or decreasing the length of a telescopic
tensioner arm 175.
[0088] It is apparent that by moving the tensioner hose guide 165
away from the first arm section 110a, the deflection of the path of
the flexible hose 150 is increased e.g. with respect to the
shortest path between proximal end 170 and first hose guide 140a.
FIG. 1 shows a second configuration of the hose tensioner 160'
comprising tensioner hose guide 165' having an increased deflection
of the path of the flexible hose 150.
[0089] For a fixed length of flexible hose 150 attached to the
fluid first manifold 310, increasing the deflection of the path of
the flexible hose 150, for instance by moving the tensioner hose
guide 165 along a non-zero path angle .alpha. away from the first
arm section 110a, would lead to distal end 180 being drawn towards
the second hose guide 140b at the end of the second arm section
110b. If the distal end 180 were attached to a fluid second
manifold, this would increase the tension of the flexible hose 150.
However, if the position of the distal end 180 of the flexible hose
150 attached to a fluid second manifold were to approach that of
second hose guide 140b, for instance due to the effect of upward
wave heave on a floating structure to which the distal end 180 was
attached, then increasing the deflection of the path of the
flexible hose 150 by the hose tensioner 160 could reduce the length
of flexible hose extending beyond second hose guide 140b. Thus,
maintaining the flexible hose 150 under constant tension via the
hose tensioner 160 can prevent the flexible hose sagging under an
upwards heave motion.
[0090] Similarly, decreasing the deflection of the path of the
flexible hose 150, for instance by moving the tensioner hose guide
165 along a non-zero path angle .alpha. closer to the first arm
section 110a, would lead to distal end 180 being lowered away from
the second hose guide 140b at the end of the second arm section
110b, for instance to compensate for a downward heave wave motion.
Thus, maintaining the flexible hose 150 under constant tension via
the hose tensioner 160 can prevent the flexible hose from becoming
over tensed under a downwards heave motion. It will be apparent
that the hose tensioner 160 may also compensate for other wave
motions, such as sway and surge, which would also result in changes
of the distance between the distal end 180 of the flexible hose and
the second hose guide 140b.
[0091] In operation, once the configuration of the arm sections 110
of the articulated arm 100 is fixed i.e. the arm section angle at
the first pivot joint is fixed, the relative movement of the fluid
second manifold can be observed with respect to the hose
manipulator 1, and particularly the base 220 or the end of the last
arm, e.g. in this embodiment, second arm 110b, particularly second
hose guide 140b.
[0092] The tensioner hose guide 160 can be moved along non-zero
path angle .alpha. by, for instance a hydraulic cylinder (not
shown). The hydraulic cylinder may be connected to first arm
section 110a, or base 220. The hydraulic cylinder can be part of
the hydraulic system.
[0093] FIG. 2 shows a second embodiment of the fluid transfer hose
manipulator 1 described herein. Where identical reference numerals
are used to those of FIG. 1, equivalent components are referred to.
In this embodiment, the hose guides 140a, 140b and 165 are present
as sheaves. The sheaves may be connected to the arm sections 110,
for instance at the pivot joints 130, typically sharing the same
axis of rotation of the pivot joint and/or at an end of the
longitudinal axis 120 of an arm section 110.
[0094] In this embodiment, the hose tensioner 160 is connected to
the base 220 of the hose manipulator 1. The hose tensioner 160
comprises a tensioner hose guide 165, which is a sheave, and a
tensioner arm 175. In this embodiment, the tensioner arm may be of
fixed length. In contrast to the embodiment of FIG. 1, the path of
the flexible hose 150 is deflected by an arcuate movement of the
sheave tensioner hose guide 165, by tensioner arm 175 rotating
about tensioner pivot joint 225 on the base 220. The deflection of
the path of the hose can be described by measuring the non-zero
angle .beta., between the base 220 and the tensioner arm 175.
[0095] FIG. 2 shows a second configuration of the hose tensioner
160' comprising tensioner hose guide 165' having an decreased
deflection of the path of the flexible hose 150 between the
proximal end 170 and the first hose guide 140a. A decreased
deflection is achieved by increasing the non-zero angle .beta. to
.beta.'. The hose tensioner 160 can be moved along its arcuate path
by, for instance, connecting tensioner arm 175 to a hydraulic
cylinder (not shown) to move the arm and thereby the hose tensioner
hose guide 160. The hydraulic cylinder can also be fixed to the
base 220 or first arm section 110a. The hydraulic cylinder can be
connected to the hydraulic system discussed.
[0096] When the articulated arm 100 is in a fixed configuration
i.e. the first pivot joint 130a is set at a fixed arm section angle
between the first and second arm sections 110a, b and distal end
180 of the flexible hose 150 is unconnected to a fluid second
manifold, the second configuration of hose tensioner 160' will
result in a lower vertical position of the distal end 180', with
respect to base 220. Thus, when the distal end 180 of the flexible
hose 150 is connected to a fluid second manifold and the vertical
position of the fluid second manifold, with respect to base 220,
changes from position 180 to the position of the distal end 180',
for instance as a result of a downward heave wave motion of the
fluid second manifold (and the floating structure to which it is
attached), this movement can be compensated for, and the tension on
the flexible hose 150 maintained, by moving the hose tensioner to
position 160'.
[0097] FIG. 3 shows a preferred embodiment of the fluid transfer
hose manipulator 1 as described herein. Identical reference
numerals to those of FIG. 1 or
[0098] FIG. 2 correspond to equivalent components. In this
embodiment, the hose manipulator comprises a first and a second
flexible hose 150a, 150b respectively, each with independent first
and second hose tensioners 160a, 160b respectively. The first and
second flexible hoses 150a, 150b may be of 20.32 cm (8 inch)
internal bore diameter and 30 m in length.
[0099] A manifold platform 330 may also be present where the base
220 is connected to the first arm section 110a, to facilitate
inspection of the hose manipulator and particularly the connection
of fluid first manifold 310 to the proximal ends of the first and
second hoses 150a, 150b.
[0100] The articulated arm 100 comprises first, second and third
arm sections 110a, 110b and 110c. The first arm section 110a can be
secured at one longitudinal end to base 220. The first arm section
110a is connected at its other longitudinal end to the second arm
section 110b by a first pivot joint (not shown). The movement of
the first pivot joint can be achieved by first arm section
hydraulic cylinder 230a. First hose guide 140a, which is present as
a sheave, can share the same axis of rotation as the first pivot
joint.
[0101] Second and third arm sections 110b, 110c are connected by a
second pivot joint (not shown). The movement of the second pivot
joint can be achieved by second arm section hydraulic cylinder
230b. Second hose guide 140b, which is present as a sheave, can
share the same axis of rotation as the second pivot joint. A third
hose guide 140c, which is present as a sheave, is positioned at the
opposite end of the longitudinal axis of the third arm section 110c
from the second pivot joint. The first, second and third sheave
hose guides 140a, 140b, 140c may have a similar composition to
those of the embodiment of FIG. 2.
[0102] The third arm section 110c may comprise a guide-way to
support and/or direct each flexible hose 150a, 150b between the
respective second and third hose guides 140b, 140c. The guide-way
may be comprised of a metal or alloy, such as aluminium or 9 wt %
nickel steel and may optionally be lined with a friction reducing
material such as TEFLON.TM..
[0103] In this embodiment, the first, second and third hose guides
140a, 140b, 140c are present in pairs, with each of the first and
second flexible hoses 150a, 150b having dedicated first, second and
third hose guides. First and second hose tensioners 160a, 160b are
provided, one for each of the first and second flexible hoses 150a,
150b. The hose tensioners 160a, 160b are present on the second arm
section 110b. Correspondingly, the nominal path 155a (for the first
flexible hose 150a) is suitably taken to the defined by the line
that tangentially connects the first hose guides 140a and the
second hose guide 140b (which first and second hose guides are
adjacent to each other). This is an advantageous configuration,
because it provides a greater range of movement to each hose
tensioner, allowing an increase in the maximum deflection of the
flexible hoses 150a, 150b. It is preferred that the hose tensioners
160a, 160b operate independently. Consequently, the first and
second flexible hoses 150a, 150b can carry fluids of different
density, temperature and/or pressure etc., while still maintaining
the flexible hoses under constant tension.
[0104] Each hose tensioner 160a, 160b comprises a tensioner hose
guide, present as a sheave, and a tensioner hydraulic cylinder
240a, 240b. The tensioner hydraulic cylinders 240a, 240b can each
move the tensioner hose guide along a path at 90.degree. to the
longitudinal axis of the second arm section 110b, parallel to the
plane defined by any two of the longitudinal axes of the three arm
sections 110a, 110b, 110c. In this way, the path of each of the
flexible hoses 150a, 150b can be deflected from the respective
nominal paths between the first and second hose guides 140a,
140b.
[0105] Each flexible hose 150a, 150b is connected at a proximal end
to fluid first manifold 310 by a connector. In the embodiment of
FIG. 3, both flexible hoses are connected to the same fluid
manifold by a first Y-connection. The first Y-connection may have
lines for the purging, draining and/or drying of the flexible hose.
The first Y-connection may further comprise orifice plates to
reduce the effects of a fluid surge. However, in an alternative
embodiment (not shown), the first and second hoses 150a, 150b could
be connected to different fluid manifolds, carrying the same or
different fluids.
[0106] The distal end of each flexible hose 150a, 150b may comprise
a restriction cone 190a, 190b and an optional emergency release
coupling 210a, 210b. The emergency release coupling 210a, 210b of
each flexible hose can be linked to a fluid connector, here
provided in the form of a second Y-connector 200 so that both
flexible hoses may transfer fluid to the same fluid manifold. The
second Y-connector 200 may have lines for the purging, draining
and/or drying of the flexible hoses 150a, 150b. The second
Y-connector may further comprise orifice plates to reduce the
effects of a fluid surge.
[0107] The emergency release couplings 210a, 210b operate to sever
the connection between the flexible hose 150a, 150b and the second
Y-connector, thereby releasing the flexible hoses 150a, 150b from
their attachment to the fluid second manifold, should there be
insufficient time to achieve disconnection via the second
Y-connector 200. The emergency release couplings 210a, 210b may
each comprise double valves to minimise any spillage from the
flexible hoses 150a, 150b and fluid second manifold upon emergency
disconnection.
[0108] The first and second arm section hydraulic cylinders 230a,
230b, the tensioner hydraulic cylinders, 240b and the emergency
release couplings 240a, 240b can form part of the hydraulic system.
The hydraulic system may be operated by a programmable logic
controller. The programmable logic controlled can be provided with
the positions of the hydraulic cylinders, in order to determine the
arm section angles, and tension of the flexible hose.
[0109] Furthermore, the addition of an accumulator to a high
pressure circuit in the hydraulic system will ensure that emergency
release is possible, particularly with regard to severing the
connection between the first and second flexible hoses 150a, 150b
and the second Y-connector 200 and to the retraction of the
articulated arm 100 and flexible hose 150a, 150b, even in the event
of the loss of electrical or hydraulic power. The hydraulic lines
to the emergency release coupling 210a, 210b may be provided by an
umbilical line (not shown) to a distribution block on a tie bar
250. The tie bar 250 may link the first and second flexible hoses
150a, 150b, typically below restriction cones 190a, 190b (which may
be provided in the form of restriction collars 190a, 190b). The
umbilical line may be supported by a guide wire (not shown).
[0110] The fluid transfer hose manipulator 1 may further comprise a
position monitoring system to monitor the position of the distal
ends of the flexible hoses 150a, 150b. This position is preferably
monitored relative to a position on the hose manipulator, such as
on an arm section 110a, 110b, 110c or base 220. By monitoring the
position of the distal ends of the flexible hoses 150a, 150b, it
can be determined whether the hose manipulator is functioning
within an acceptable operating envelope. For instance, a narrow
connection limit operating envelope may be defined, with a broader
warning limit envelope and a still broader disconnect limit
envelope. If the distal ends of the flexible hoses 150a, 150b
exceed the disconnect limit envelope, the emergency release
coupling can be activated, for instance via the hydraulic system
through the umbilical line.
[0111] The position monitoring system may be connected to the
programmable logic controller which can control, via the hydraulic
system, one of more, preferably all of: the configuration of the
arm sections 110 of the articulated arm 100, the tension of the
flexible hose 150 via the hose tensioner 160 and the emergency
release coupling 210.
[0112] The position monitoring system may be, for instance a guide
wire and gimbal system. The guide wire may be connected between tie
bar 250 on the distal ends of the flexible hoses 150a, 150b and a
gimbal head located on the end of the third arm section 220c having
third hose guide 140c. A sensor, such as a laser, can measure the
angle of the guide wire at the gimbal head. The location of the
distal end of the flexible hose 150a, 150b can therefore be
determined from the gimbal head angle and the length of the guide
wire for a given hose tensioner 160a, 160b position.
[0113] For instance, the embodiment of FIG. 3 having a flexible
hose length of approximately 30 m, and a minimum mooring separation
of 3.7 m between the FLSO carrying the fluid transfer hose
manipulator and the LNG carrier vessel, the hose manipulator may
operate in sea conditions with relative dynamic motions between the
vessels of +/-0.75 m for each of heave, surge and sway.
[0114] Multiple hose manipulators may be provided on the FLSO, for
instance, four or five hose manipulators, each comprising two
flexible hoses, may be located on the manifold platform.
[0115] FIGS. 4A, 4B and 4C illustrate three configurations 1a, 1b
and 1c of the fluid transfer hose manipulator 1 according to the
embodiment of FIG. 3 on an FLSO 300.
[0116] FIG. 4A shows the hose manipulator 1 in a storage
configuration 1a, when not in use for fluid transfer. The first arm
section is fixed immovably to the base 220, with its longitudinal
axis vertical, while second and third arm sections are in a
substantially vertical configuration along their longitudinal axes
by virtue of the first and second pivot joints and first and second
arm section hydraulic cylinders. It will be apparent that this
configuration is advantageous for storage because it minimises the
footprint of the hose manipulator 1.
[0117] FIG. 4B shows the hose manipulator 1 in an operational
configuration 1b, when transferring LNG to an LNG carrier vessel
400. This operational configuration can be adopted when the fluid
second manifold 410 on the carrier vessel 400 is at substantially
the same height as the base 220 of the hose manipulator 1. This may
occur, for instance, when the LNG carrier vessel 400 is a 145,000
m.sup.3 carrier. The first arm section can be fixed immovably to
the base 220, with its longitudinal axis vertical, the second arm
section can be held with its longitudinal axis in a substantially
vertical orientation by virtue of the first pivot joint and first
arm section hydraulic cylinder, while the third arm section can be
held, by second arm section hydraulic cylinder and the second pivot
joint, at an angle of typically -20 to +20 .degree. from the
horizontal, more typically -15 to +15 .degree. from the horizontal,
measured from the axis of the second pivot joint. As used herein,
the term "substantially vertical" is intended to mean within
+/-10.degree. of vertical.
[0118] FIG. 4C shows the hose manipulator 1 in an operational
configuration 1c, when transferring a fluid to an LNG carrier
vessel 400. This operational configuration can be adopted when the
fluid second manifold 410 on the LNG carrier vessel 400 is at
substantially lower height than the base 220 of the hose
manipulator 1. This may occur, for instance, when the LNG carrier
vessel 400 is a 10,000 m.sup.3 carrier. The first arm section can
be fixed immovably to the base 220, with its longitudinal axis
vertical, the second arm section can be held, by the first pivot
joint and first arm section hydraulic cylinder, with its
longitudinal axis at an angle of from -10 to -30.degree. from the
horizontal measured from the first pivot joint, while the third arm
section can be held substantially vertically by second arm section
hydraulic cylinder and the second pivot joint.
[0119] In a further embodiment, a method of transferring a fluid,
such as a cryogenic fluid, for instance LNG, between first and
second structures using a hose manipulator described herein is also
disclosed. The method is particularly advantageous when at least
one, typically both, of the first and second structures is a
moveable structure, preferably a floating structure.
[0120] The method may comprise providing a fluid transfer hose
manipulator as described herein on a first structure. The first
structure may be a first non-floating structure, like an off-shore
platform or a jetty or the first structure may be a first floating
structure, typically a FSO, FPSO, FLSO or carrier vessel. The hose
manipulator may be in a storage configuration, as described above
and shown as 1a in FIG. 4A. The hose manipulator can be connected
to a fluid first manifold, which is in fluid communication with one
or more fluid first storage tanks 340. The one or more fluid first
storage tanks 340 may be one or more of insulated, cooled and
pressurised first fluid storage tanks, particularly if the fluid to
be transferred is a cryogenic fluid such as LNG. The one or more
fluid first storage tanks may be empty or partially full, if the
fluid is to be transferred to these tanks, of full or partially
full, if the fluid is to be transferred from these tanks.
[0121] A second structure can be provided. The second structure may
be a first non-floating structure, like an off-shore fixed platform
or a jetty or the second structure may be a first floating
structure, typically a FSO, FPSO, FLSO or carrier vessel. The
second structure may comprise a fluid second manifold, in fluid
communication with one or more fluid second storage tanks 440.
These one or more fluid second storage tanks may be similar to the
fluid first storage tanks already discussed.
[0122] The fluid second manifold of the second structure should be
aligned with the hose manipulator, typically a flexible hose of the
hose manipulator, more typically the distal end of a flexible hose,
still more typically a connector of a second end, such as a
Y-connection, of the first structure. This alignment may be
achieved by moving one or both of the first and second structures.
For instance, when one or both of the first and second structures
are floating structures, they can be positioned at a minimum
distance of 3.7 m. When both first and second structures are
floating vessels, the alignment may be achieved by a side-by-side
arrangement e.g. starboard to port or port to port or port to
starboard of the two vessels.
[0123] In one embodiment, the maximum vertical distance between
first and second fluid manifolds is in the range of from -19.2 m to
+3.7 m. The maximum horizontal distance between first and second
manifolds is in the range of from 9.6 m to 13.6 m. The maximum
lateral misalignment between first and second manifolds is in the
range of from -1.05 m to +1.05 m.
[0124] In one embodiment, the first and second structures are
floating structures. For instance, the first structure is an FLSO
300 and the second structure is an LNG carrier vessel 400 as shown
in FIGS. 4B and 4C. In another embodiment, one of the first and
second structures is a floating structure and the other is a
non-floating structure, for instance, the first structure may be a
jetty, while the second structure may be an LNG carrier vessel.
Typically, the first structure may be the jetty of an LNG import or
export terminal and the second structural may be an LNG carrier
vessel.
[0125] Once the fluid second manifold is aligned, the hose
manipulator can be moved from storage position 1a into the
operating position. The configuration of the operating system will
depend on the height of the fluid second manifold 410 versus that
of base 220. FIGS. 4B and 4C show two potential operational
configurations 1b and 1c.
[0126] Once the correct operational position such as 1b, 1c has
been adopted, a connector, such as a Y-connector, at the distal end
of the flexible hose may be connected to the fluid second manifold
410 of the second floating structure, such as LNG carrier vessel
400. This can be achieved by bolting the connector to the fluid
second manifold 410.
[0127] The flexible hose can then be purged. For instance, when the
fluid to be transferred is LNG, the purge fluid may be
nitrogen.
[0128] The fluid, such as LNG, can then be transferred between
first and second structures, such as the FLSO 300 and LNG carrier
vessel 400. Once the fluid transfer has been completed, the
flexible hoses can then be purged with purge fluid, such as
nitrogen. The connector of the distal end of the flexible hose may
then be disconnected from the fluid second manifold 410. The hose
manipulator may then be returned to storage configuration la. The
first and second structures may then be moved apart.
[0129] The person skilled in the art will understand that the
present invention can be carried out in many various ways without
departing from the scope of the appended claims.
[0130] For instance, one or more of the arm sections, typically the
section furthest along the articulated arm from the first arm
section connected to the base, may be telescopic. In particular,
such a telescopic arm section could be configured to change the
length of the arm section along its longitudinal axis. The length
may be changed by a hydraulic cylinder, which can be connected
* * * * *