Note: Descriptions are shown in the official language in which they were submitted.
CA 02582213 2013-10-17
DUAL CONTAINMENT SYSTEMS, METHODS AND KITS
FIELD OF THE INVENTION
[0002] The present invention relates generally to the field of spoolable
tubing, and
more particularly to a spoolable tube for conveying a fluid including an inner
layer and a
reinforcing layer.
BACKGROUND
[0003] Transporting fluids and mixtures of fluids may require careful
handling, for
example, when a fluid mixture includes a toxic fluid. An example of such a
fluid is sour
gas, which is natural gas that may contain up to, or over, 20% hydrogen
sulfide
contaminant by weight. Sour gas may also contain aromatic hydrocarbons, for
example,
benzene, toluene, xylenes and ethylbenzene. As is well known, hydrogen sulfide
and such
aromatic hydrocarbons may be toxic.
[0004] For example, the presence of hydrogen sulfide (H2S) in transportable
fluids can
give rise to critical safety problems. In humans, the recommended exposure
limit for H2S
is 10 ppm per 10 minutes of exposure. The gas is immediately lethal at a
concentration of
about 300 ppm, which is comparable to the toxicity of hydrogen cyanide. The
human nose
can detect concentrations as low as 0.02 ppm and its maximum sensitivity is
about 5 ppm;
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the nose becomes increasingly unable to detect hydrogen sulfide at
concentrations of 150-
200 ppm.
[0005] The presence of hydrogen sulfide and other toxic fluids also brings
special
demands on the materials for installations handling and the transport of
fluids, as many
metals are sensitive to, for example, sulfide stress cracking. During
transport along a pipe,
for example, fluids such as sour gas may partially separate and/or permeate
the pipe, thus
releasing toxic fluids into the pipe surroundings. When such a pipe includes
for example an
outer jacket, such escaped fluids may potentially cause burst or fracture of
the pipe and/or
the outer jacket.
[0006] Spoolable tubing, or tubing capable of being spooled upon a reel, is
commonly
used in numerous oil well operations, although other applications exist. For
example,
spoolable pipe may be used in gathering applications that, for example,
transport produced
fluids from the individual well head to transportation pipeline, or in other
oil well operations
include running down hole with well tools, or working over wells by delivering
various
chemicals down hole, and performing operations on the interior surface of the
well bore.
The tubes are spoolable so that a tube for example, can be used in long
continuous lengths
with a minimum number of joints, or with one well, and then transported on a
reel to another
well at a different location.
[0007] There is a need for a system that includes spoolable pipe which may
not be
susceptible to, for example, gas contaminants, and/or that provides for
removal of such
contaminants in a safe manner.
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[0008] The procedure to construct a composite tube that is capable of
spooling for
transport or deployment, and able to resist high internal pressure loads or
axial tensile or
compressive loads involves using complex composite mechanics engineering
principles to
ensure that the tube has sufficient strength. Examples of composite tubes are
presented in
U.S. Patents 5,921,285, 6,016,845, 6,004,639, 6,148,866, 6,286,558, 6,357,485,
and
6,604,550.
SUMMARY
[0009] Disclosed is a system for conveying a fluid comprising a spoolable
tube
comprising an inner layer which defines a first passage for conveying a first
fluid; and an
outer layer, where the spoolable tube also includes a second passage for
conveying a
second fluid and one or more fittings adapted to engage an axial end of said
inner layer
and an axial end of said outer layer.
[0010] For example, a system conveying a fluid is disclosed comprising: a
spoolable
tube that comprises an inner layer, where the inner layer comprises a first
layer and a
reinforcing layer comprising fiber and wherein the inner layer defines a first
passage for
conveying a first fluid, an outer layer; an annular space between the inner
and the outer
layer defining a second passage for conveying a second fluid; and one or more
fittings
adapted to engage an axial end of the inner layer and an axial end of the
outer layer. The
first passage may be capable of conveying a first fluid at a first pressure
and the second
passage may be capable of conveying said second fluid at a second pressure.
For example,
the pressure of a second fluid transported within the second passage may be
less than or
equal to the pressure of the first fluid transported in the first passage.
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[001111 In some embodiments, a second passage may comprise one or more
physical
perturbations such as channels or grooves. In other embodiments, the outer
surface of the
inner layer and/or the inner surface outer layer may include a physical
perturbation such as a
post, ridge, cleft, bump, groove or channel, and may be in some embodiments
axially or
helically oriented. Such a physical perturbation may be discontinuous or
continuous along
the axial length of the tube. For example, the outer surface of a reinforcing
layer may
include an axial or helically placed multi-filament yarn.
100121 The system disclosed herein includes a fitting. Such a fitting may
comprise a
first seal adapted to reversibly seal the first passage of the pipe disclosed
herein and may also
comprise a second seal adapted to reversibly seal the second passage of the
pipe. The fitting
may include a means to measure the pressure of the second fluid and/or a means
to measure
the pressure of the first fluid. Alternatively or additionally, the fitting of
the system may
include a means to limit the pressure of the second fluid, for example, the
system or fitting
may include a relief valve such as those known to persons skilled in the art.
[0013] The system may include a tube, wherein the first layer of the tube
may comprise
one or more of a polymer, an elastomer, or a metal. In some embodiments, the
first layer
may comprise a thermoplastic, such as for example, high density polyethylene,
crosslinked
polyethylene, polyvinylidene fluoride, polyamide, polyethylene terphthalate,
or
polypropylene, and combinations thereof. The tube of the disclosed system may
include an
outer layer that comprises one or more of a polymer, an elastomer, or a metal.
In one
embodiment, the outer layer comprises a thermoplastic, such as for example,
high density
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polyethylene, crosslinked polyethylene, polyvinylidene fluoride, polyamide,
polyethylene
terphtlialate, or polypropylene, and combinations thereof.
100141 A reinforcing layer of the disclosed tubes may include fiber, such a
glass, an
aramid, a metal, a carbon, a ceramic, or a mineral, or combinations of these.
Such a
reinforcing layer may further comprise a matrix. For example, a reinforcing
layer may
include fibers embedded or encapsulated in a matrix, for example, embedded or
encapsulated in a polymer such as for example a thermoplastic, or epoxy.
100151 The tubes, systems, and kits disclosed herein may also include an
energy
conductor or a data conductor. Such an energy conductor may be disposed
within, attached,
or adjacent to a reinforcing layer of the tube, or an energy conductor may be
disposed
between the inner layer and the outer layer. An energy conductor may include a
fiber optic
cable, a fiber optic sensor, a metal, or an insulated metal. The disclosed
fittings may also
include a connection for an energy conductor or a data conductor.
100161 The disclosed systems and kits also may include a fitting where, in
one
embodiment, the fitting may be adapted to engage said reinforcing layer and/or
said outer
layer, and/or adapted to seal on said inner layer and said outer layer.
100171 The disclosed systems may further comprise a means to vent a first
fluid
transported or conveying within the first passage, and/or a means to vent a
second fluid
transported or conveying within the second passage.
[00181 Another aspect of this disclosure is a method for containment of a
fluid,
comprising providing a tube comprising an inner layer defining a first fluid
pathway and an
outer layer, thereby forming a second fluid pathway, or annulus, between said
inner and
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outer layer, reversibly sealing said first fluid pathway at an axial end of
said tube; and
reversibly sealing said annulus at an axial end of said tube. The method may
further
comprise measuring the pressure of the fluid within the first fluid pathway
and measuring
the pressure of the fluid within the armulus. The method may further comprise
limiting a
first pressure of a first fluid in the first fluid pathway so that said first
pressure is less than
a pressure of a second fluid in the second fluid pathway.
[00191 In another aspect, a containment kit is disclosed herein comprising:
a pipe
comprising a thermoplastic inner layer, a reinforcing layer, and an outer
layer, that includes
at least two distinct passages for fluid; and a fitting that reversibly seals
the two distinct
passages for fluid.
[0019a] In another aspect, the present invention provides a system for
conveying a fluid
comprising: a spoolable tube comprising: an inner layer which defines a first
passage for
conveying a first fluid, wherein said inner layer comprises a first layer and
a reinforcing
layer comprising fiber; an outer layer; an annular space between said inner
and said outer
layer defining a second passage comprising a plurality of channels for
conveying a second
fluid, wherein the plurality of channels extend substantially along an axial
length of the
spoolable tube; and, one or more fittings adapted to engage an axial end of
said inner layer
and an axial end of said outer layer, wherein said fitting comprises a first
seal adapted to
reversibly seal said first passage directly from the atmosphere or separate
containment
device and a second seal adapted to reversibly seal said second passage
directly from the
atmosphere or separate containment device, said one or more fittings
comprising a
connection for an energy conductor.
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4
[0019aa] More preferably, the second passage further comprises grooves.
10019b1 In yet another aspect, the present invention provides a method for
containment
of a fluid, comprising: providing a tube comprising an inner layer defining a
first fluid
pathway and an outer layer thereby forming a second fluid pathway between said
inner and
outer layer, said second fluid pathway comprising a plurality of channels
extending
substantially along an axial length of the tube; reversibly sealing said first
fluid pathway
directly from the atmosphere or separate containment device at an axial end of
said tube;
and reversibly sealing said second fluid pathway directly from the atmosphere
or separate
containment device at an axial end of said tube with a fitting comprising a
connection for an
energy conductor.
[0019c] In yet another aspect, the present invention provides a
containment kit
comprising: a pipe comprising a thermoplastic inner layer, a reinforcing
layer, and an outer
layer, that includes at least two distinct passages for fluid, at least one of
the passages
comprising a plurality of channels extending substantially along an axial
length of the tube;
and a fitting that reversibly seals the two distinct passages for fluid
directly from the
atmosphere or separate containment device, the fitting comprising a connection
for an
energy conductor.
[0020] Other objects and advantages will become apparent
hereinafter in view of the
specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In the drawings, like reference characters generally refer
to the same parts
throughout the different views. Also, the drawings are not necessarily to
scale, emphasis
instead generally being placed upon illustrating the principles of the
invention. In the
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following description, various embodiments of the present invention are
described with
reference to the following drawings, in which:
[0022] FIGURE 1 is a side view, partially broken away, of a system that
includes a
spoolable tube with an inner layer and an outer layer with an annulus formed
between the
inner and outer layer and includes a fitting that includes a seal that seals a
first fluid pathway
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and a seal that seals a second fluid pathway, in accordance with one
embodiment of the
invention;
100231 FIGURE 2 is a cross-sectional view of a spoolable tube that includes
an inner
layer, and an outer layer with an annulus formed between the inner and outer
layer, in
accordance with one embodiment of the invention;
[00241 FIGURE 3 is a cross-sectional view of a spoolable tube that includes
an inner
layer forming a first passage and an outer layer, where a physical
perturbation forms a
second passage, in accordance with one embodiment of the invention; and
[00251 FIGURE 4 is a cross-sectional view of a spoolable tube including a
plurality of
channels located between a reinforcing layer, and an outer layer, in
accordance with one
embodiment of the invention.
DETAILED DESCRIPTION
100261 To provide an overall understanding, certain illustrative
embodiments will now
be described; however, it will be understood by one of ordinary skill in the
art that the
systems and methods described herein can be adapted and modified to provide
systems and
methods for other suitable applications and that other additions and
modifications can be
made without departing from the scope of the systems and methods described
herein.
100271 Unless otherwise specified, the illustrated embodiments can be
understood as
providing exemplary features of varying detail of certain embodiments, and
therefore, unless
otherwise specified, features, components, modules, and/or aspects of the
illustrations can be
otherwise combined, separated, interchanged, and/or rearranged without
departing from the
disclosed systems or methods. Additionally, the shapes and sizes of components
are also
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exemplary and unless otherwise specified, can be altered without affecting the
scope of the
disclosed and exemplary systems or methods of the present disclosure.
[002811 Disclosed is a spoolable tube that provides one, two, or more paths
for
conducting fluids (i.e., liquids and gases) along the length of the spoolable
tube. For
example, the spoolable tube can transmit fluids down a well hole for
operations upon the
interior surfaces of the well hole, the spoolable tube can transmit fluids or
gases to hydraulic
or pneumatic machines operably coupled to the spoolable tube, and/or the
spoolable tube can
be used to transmit fluids on surface from well holes to transmission or
distribution
pipelines. Accordingly, the spoolable tube can provide one, two or more
conduits for
powering and controlling hydraulic and/or pneumatic machines, and/or act as a
conduit for
fluids, for example gases or liquids.
1002911 Figures 1 and 2 illustrate a system 100 that includes a tube 10
constructed of a
first layer 12, a reinforcing layer 14 and at least one external layer 16 that
may enclose the
reinforcing layer(s) 14. The spoolable tube can be generally formed along a
longitudinal
axis 17. Although illustrated in Figure 1 as having a circular cross-section,
the disclosed
spoolable tube can have a variety of tubular cross-sectional shapes, including
but not limited
to circular, oval, rectangular, square, polygonal, and/or others.
[003011 First layer 12, otherwise referred to as a liner, can serve as a
pressure containment
member to resist leakage of internal fluids from within the spoolable tube 10.
In some
embodiments, the first layer 12 can include a polymer, a thermoplastic, an
elastomer, a
rubber, a metal, co-polymer, and/or a composite. The composite can include a
filled
polymer and/or a nano-composite. Accordingly, first layer 12 can include one
or more of a
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high density polyethylene (HDPE), a cross-linked polyethylene (PEX), a
polyvinylidene
fluoride (PVDF), a polyamide, polyethylene terphthalate, polyphenylene sulfide
and/or a
polypropylene. In one embodiment, the first layer 12 includes a modulus of
elasticity greater
than about approximately 50,000 psi, and/or a strength greater than about
approximately
1,000 psi.
100311 Referring back to Figure 1, the spoolable tube 10 can also include
one or more
reinforcing layers 14. In one embodiment, the reinforcing layers can include
fibers having,
for example, at least a partially helical orientation relative to the
longitudinal axis of the
spoolable tube. The fibers may have a helical orientation between
substantially about thirty
degrees and substantially about seventy degrees relative to the longitudinal
axis 17. For
example, the fibers may be counterwound with a helical orientation of about
40 , 45 ,
50 , 55 , and/or 60 . The reinforcing layer may include fibers having
multiple, different
orientations about the longitudinal axis. Accordingly, the fibers may increase
the load
carrying strength of the reinforcing layer(s) 14 and thus the overall load
carrying strength of
the spoolable tube 10. In another embodiment, the reinforcing layer may carry
substantially
no axial load carrying strength along the longitudinal axis at a termination.
100321 Exemplary fibers include but are not limited to graphite, KEVLAR,
fiberglass,
boron, polyester fibers, polymer fibers, mineral based fibers such as basalt
fibers, and
aramid. For example, fibers can include glass fibers that comprise e-cr glass,
Advantex , s-
glass, d-glass, or a corrosion resistant glass.
100331 The reinforcing layer(s) 14 can be formed of a number of plies of
fibers, each ply
including fibers. In one embodiment, the reinforcing layer(s) 14 can include
two plies,
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which can optionally be counterwound unidirectional plies. The reinforcing
layer(s) can
include two plies, which can optionally be wound in about equal but opposite
helical
directions. The reinforcing layer(s) 14 can include four, eight, or more plies
of fibers, each
ply independently wound in a helical orientation relative to the longitudinal
axis. Plies may
have a different helical orientation with respect to another ply, or may have
the same helical
orientation. The reinforcing layer(s) 14 may include plies and/or fibers that
have a partially
and/or a substantially axial orientation. The reinforcing layer may include
plies of fibers
with an abrasion resistant material disposed between each ply, or optionally
disposed
between only certain plies. In some embodiments, an abrasion resistant layer
is disposed
between plies that have a different helical orientation.
100341 The fibers can include structural fibers and flexible yarn
components. The
structural fibers can be formed of carbon, aramid, thermoplastic, and/or
glass. The flexible
yarn components, or braiding fibers, can be formed of either polyamide,
polyester, aramid,
thermoplastic, glass and/or ceramic. The fibers included in the reinforcing
layer(s) 14 can be
woven, braided, knitted, stitched, circumferentially (axially) wound,
helically wound, and/or
other textile form to provide an orientation as provided herein (e.g., in the
exemplary
embodiment, with an orientation between substantially about thirty degrees and
substantially
about seventy degrees relative to the longitudinal axis 17). The fibers can be
biaxially or
triaxia Ely braided. The reinforcing layer(s) and/or fibers in the reinforcing
layers can include
a coating.
100351 In one embodiment, the reinforcing layer(s) 14 includes fibers and a
matrix. The
reinforcing layer may be formed of one or more plies, each ply having one or
more fibers
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disposed or embedded within a matrix, such as a polymer, glue, resin, coating,
or
thermoplastic. The fiber material and orientation can be selected to provide
the desired
mechanical characteristics for the reinforcing layer 14.
[0036] In some embodiments, an adhesive can be used to bond the reinforcing
layer(s)
14 to first layer 12. In other embodiments, one or more reinforcing layers are
substantially
not bonded to one or more of other layers, such as the inner liner, internal
pressure barriers,
or external layer(s). First layer 12 and reinforcing layer 14 may form an
inner layer 15.
Inner layer 15 may include both a first layer 12 and a reinforcing layer 14,
or may include
only a first layer 12 or a reinforcing layer 14. Alternatively, inner layer
may include one,
two or more layers that each individually comprise a metal, polymer, rubber,
elastomer, or
other material. In some embodiments, the inner layer defines a passage for
conveying a first
fluid. For example, the inner layer may define a first passage for conveying a
first fluid that
comprises on fluid, or a mixture of fluids, one or more of which may permeate
through an
inner layer 15. Such a fluid, for example, may also be conveyed along tube of
system 100.
[0037] In certain exemplary embodiments, the matrix has a tensile modulus
of at least
100,000 psi, preferably at least 250,000 psi, and has a maximum tensile
elongation of at least
5%. In the case of a thermoset matrix, the matrix may have a glass transition
temperature of
at least 180 F. In the case of a thermoplastic matrix, the matrix may have a
melt temperature
of at least 250 F. The fibers may be structural fibers and/or flexible yarn
components. The
structural fibers may be formed of carbon, nylon, polyester, aramid,
thermoplastic, glass, or
other suitable fiber materials. The flexible yarn components, or braiding
fibers, may be
formed of nylon, polyester, aramid, thermoplastic, glass, or other suitable
fiber materials.
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The fibers included in the reinforcing layer 14 can be woven, braided,
knitted, stitched,
circumferentially wound, or helically wound. In particular, the fibers can be
biaxially or
triaxially braided. The reinforcing layer 14 can be formed through pultrusion
processes,
braiding processes, or continuous filament winding processes. In certain
exemplary
embodiments, a tube formed of the liners and the composite layers disclosed
herein may
form a composite tube having a tensile strain of at least 0.25 percent and
being capable of
maintaining an open bore configuration while being spooled on a reel.
[0038] In some embodiments, external or outer layer 16 forms a second
passage for
conveying a second fluid, or annulus 20, between outer layer 16 and inner
layer 15. Such
fluid may be a result of fluid permeating through inner layer 15 to annulus
20. The outer
layer(s) 16 may otherwise be understood to be an outer protective layer. In
some
embodiments, the external layer 16 is substantially unbonded to one or more of
the
reinforcing layer(s) 14, or substantially unbonded to one or more plies of the
reinforcing
layer(s) 14. The outer layer may be of unitary construction. In some
embodiments, a second
passage conveyed along annulus 20 may be capable of conveying a second fluid,
where, in
some embodiments, the second fluid is less than or equal to the pressure of a
first fluid
conveyed in the passage formed from an inner layer.
[0039] Annulus or fluid pathway 20 may further include one or more, or a
plurality of,
formed grooves or channels. Such grooves or channels may be formed from, for
example, a
polymer such as a thermoplastic. Grooves or channels within annulus 20 may be
longitudinal passages that extend substantially or partially along the axial
length of pipe 10.
Such grooves may create axial flow paths for fluids that may permeate into the
annulus from
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within inner layer of the composite tube. Such axial flow paths may terminate
at an axial
end of a tube.
[004011 An example embodiment of the invention, including a plurality of
channels 20,
can be seen in Figure 4. This embodiment can include a spoolable tube 10
including a first
layer 12, at least one reinforcing layer 14, and at least one external layer
16 that may enclose
the reinforcing layer(s) 14. A plurality of channels 20 can be located between
the
reinforcing layer 14 and at least one external layer 16 to provide a plurality
of axial flow
paths between these layers. In an alternative embodiment, these channels 20
may be located
between any two or more layers of a spoolable tube 10.
[0041] In one embodiment, the channels 20 can be cut, molded, extruded or
otherwise
created on an inner surface of the external layer 16 during manufacture of the
spoolable tube
10. Alternatively, the channels 20 can be cut, molded, extruded or otherwise
created on an
outer surface of the reinforcing layer 14, or created in both the inner
surface of the external
layer 16 and the outer surface of the reinforcing layer 14 in combination. In
an alternative
embodiment, the channels 20 can include separate hollow thin walled elements
placed
between the reinforcing layer 14 and at least one external layer 16 during or
after
manufacturing. These thin walled channels can be manufactured from a metal,
plastic,
composite material, or any other appropriate material with the required
strength and thermal
properties to provide appropriate flow paths between two or more layers of the
spoolable
tube 10.
[0042] Any number of channels 20 can be placed between the reinforcing
layer 14 and at
least one external layer 16, as required. These channels 20 can be placed at
regular intervals
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around the circumference of the inner surface of the external layer 16, as
shown in Figure 4,
or be located at one or more discrete, irregularly spaced locations around the
inner surface of
the external layer 16. In an alternative embodiment, a single channel may be
located
between the reinforcing layer 14 and at least one external layer 16.
[0043] In one embodiment of the invention, the plurality of channels 20 can
be
configured to run parallel, or substantially parallel, with a longitudinal
axis of the spoolable
tube 110. In an alternative embodiment, one or more channels 20 can be
configured to spiral
around the circumference of the inner surface of the external layer 16 at an
angle to the
longitudinal axis of the spoolable tube 10.
[0044] In one embodiment, the channels 20 can be substantially rectangular
in shape,
with the side walls configured to be substantially parallel with, or at a
shallow angle to, a
radial axis of the spoolable tube 10. In alternative embodiment, substantially
square, curved,
V-shaped, U-shaped, or any other appropriately shaped channels 20, or
combinations
thereof, may be incorporated into the spoolable tube 10. In general, these
channels may be
of any appropriate size, shape, and number to provide an appropriate flow
field between the
inner surface of the external layer 16 and the outer surface of the
reinforcing layer 14, as
required in a specific configuration of the invention.
[0045] Figures 2 and 3 illustrate a system that includes a physical
perturbation 22
disposed between the inner layer 15 and the outer layer 16. In some
embodiments, such a
perturbation may form an annulus 20, or a path for the axial movement of fluid
within an
annulus 20. For example, the outer surface of the inner layer 15 and/or the
inner surface of
the outer layer 16 may include such a physical perturbation. A physical
perturbation may
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include for example a protrusion, a channel, groove, cleft, ridge, bump, or
post. Such a
physical perturbation may be either axially or helically oriented, in part or
full, and/or a
physical perturbation can be discontinuous or continuous along the axial
length of the tube.
For example, grooves may be applied on the outer surface of the inner layer,
or the inner
surface of the outer layer or both, or applied at least partially helically or
axially to the
exterior surface of the reinforcing layer, to provide a path for the axial
movement of fluid
through a second passage 20. In another example, a physical perturbation may
include one
or more bumps or protrusions on the outer surface of the inner layer 15 and/or
the inner
surface of the outer layer 16. In an embodiment, the tubes disclosed herein
may comprise
one, two or more physical perturbations.
[0046] For example, such a physical perturbation may include one or more
multi-
filament yarns disposed helically or axially on the outer surface of the inner
layer 15 and/or
the inner surface of the outer layer 16. Such a yarn may comprise for example
glass or
polymer and may include space between the yarn filaments that may allow fluids
to move
axially between inner layer 15 and outer layer 16. Such a physical
perturbation, such as a
multi-filament yarn, may assist in the prevention of trapped fluids between
the inner and
outer layers. Such trapped fluids, that can not reach, for example, vents at
the ends of a pipe
may increase the likelihood of pipe burst.
[0047] In other embodiments, a physical perturbation 22 may include a
tracer wire that
includes a metal, for example, copper or steel. A metallic tracer wire, for
example, may
assist in ascertaining the position of a buried pipe system that is otherwise
metal free.
Physical perturbation 22 may also include, e.g. a tape, a mesh, rope, yarn,
string. Such
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embodiments of element 22 may comprise one or more of a metal, a polymer, a
plastic,
cellulose, or glass.
[00481 The outer or external layer(s) 16 can provide wear resistance and
impact
resistance. For example, the outer layer 16 can provide abrasion resistance
and wear
resistance by forming an outer surface to the spoolable tube that has a low
coefficient of
friction thereby reducing the wear on the reinforcing layers from external
abrasion. Further,
the external layer 16 can provide a seamless layer, to contain, for example, a
fluid flowing
between the inner 15 and outer layer 16. The external layer 16 can be formed
of a filled or
unfilled polymeric layer. Alternatively, the external layer 16 can be formed
of a fiber, such
as ararnid or glass, with or without a matrix. Accordingly, the external layer
16 can be a
polymer, thermoset plastic, a thermoplastic, an elastomer, a rubber, a co-
polymer, and/or a
composite, where the composite includes a filled polymer and a nano-composite.
In some
embodiments, outer layer(s) 16 can include one or more of high density
polyethylene
(HDPE), a cross-linked polyethylene (PEX), a polyvinylidene fluoride (PVDF), a
polyamide,
polyethylene terphthalate, polyphenylene sulfide and/or a polypropylene. The
outer layer 16
can include a modulus of elasticity greater than about approximately 50,000
psi, and/or a
strength greater than about approximately 1,000 psi. In an embodiment, the
outer layer 16
can carry at least ten percent, twenty percent, twenty-five percent, thirty
percent or even at
least fifty percent of an axial load in the longitudinal direction at a
termination. A seamless
external layer can comprise, for example, a seamless thermoplastic.
100491 In some embodiments, the external layer 16 can be formed by
extruding, while
the layer 16 can be formed using one or more materials applied at least
partially helically
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and/or at least partially axial along the longitudinal axis 17. The material
can include, for
example, one or more polymeric tapes. In an example embodiment, the external
layer 16 can
include and/or otherwise have a coefficient of friction less than a
coefficient of friction of a
reinforcing layer 14.
[0050] Particles can be added to the external layer 16 to increase the wear
resistance of
the external layer 16. The particles used can include one or more of ceramics,
metallics,
polymerics, silicas, or fluorinated polymers. For example, adding TEFLON (MP
1300)
particles and an aramid powder (PD-T polymer) to the external layer 16 can
reduce friction
and enhance wear resistance.
[0051] It can be understood that pressure from fluids transported by the
spoolable tubes
disclosed herein may not be properly released from the reinforcing layer(s)
14, and/or
from the inner layer 15, or the annulus 20 formed between the inner layer and
the outer layer.
Such accumulation of pressure can cause deterioration of the spoolable pipe
10, for example,
external layer rupture or inner pressure barrier collapse. Further, such
pressure may arise
from toxic fluid permeating from fluids transported within the inner layer 15.
Accordingly,
in some embodiments, to allow for capture of such fluid and/or for pressure
release along the
length of the spoolable pipe 10, the instant pipe system includes one or more
fittings. Such
fittings may be adapted to engage an axial end of the inner layer 15 and/or
the fluid path
defined by inner layer 15, and may include one or more seals 50, 52. The one
or more
fittings may also be adapted to engage an axial end of the annulus 20.
Referring to Figure 1,
seal 50 reversibly seals the fluid pathway defined by inner layer 15. Seal 52
may reversibly
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seal the annulus 20. In some embodiments, seals 50, 52 may each independently
reversibly
or irreversibly seal a fluid pathway.
[00521 For example, such couplings or fittings may engage with, be attached
to, or in
contact with one or more of the internal and external layers of a tube, and
may act as a
mechanical load transfer device. Couplings may engage one or both of the inner
liner, the
external wear layer or the reinforcing layer. Couplings or fittings may be
comprised, for
example, of metal or a polymer, or both. In some embodiments, such couplings
may allow
tubes to be coupled with other metal components, or to one or more containment
receptacles
for capturing independently fluids traveling along system 100. In addition, or
alternatively,
such couplings or fittings may provide a pressure seal or venting mechanism
within or
external to the tube. One or more couplings may each independently be in fluid
communication with the inner layer and/or in fluid communication with the
annulus formed
between the one or more reinforcing layers and/or plies of fibers and the
outer layer. Such
couplings may provide venting, to the atmosphere, or to one or more
containment devices, of
any gasses or fluids that may be present in any of the layers or annuluses
between the
external layer and the inner layer, inclusive.
[0053] The pipe or tube system may also include a pressure seal or venting
mechanism
within the pipe or tube, such as, for example, a relief valve. One embodiment
of the
invention can include a connection system to transfer a fluid contained within
the annulus
and/or within the inner layer, pass it round a seal or connection element, and
join it to
another fluid containing region, such as an annulus and or inner layer of
another adjoining or
separate tube, a storage container, or a venting container. Alternatively, the
fluid may be
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vented to the surrounding atmosphere, or to another appropriate safe or
controlled area.
Different venting mechanisms and/or connection systems may be coupled to the
annulus
and/or inner layer, as required. As a result, a fluid may be sealed within a
single inner layer
and/or annulus, connected between more than one inner layer and/or annulus,
e.g the system
is sealed across a connector, or can be vented to a separate containment
element.
[005411 With reference to Figure 2 the disclosed spoolable tubes 10 can
also include one
or more energy conductors 62 that can, for example, be integral with a wall of
the spoolable
pipe. Accordingly, the energy conductors 62 can be integral with the first
layer, reinforcing
layer(s), and/or exist between such first layer 12 and reinforcing layer 14,
and/or exist
between the inner layer 15 and an external layer 16. In some embodiments, the
energy
conductor 62 can extend along the length of the spoolable tube 10. The energy
conductors
62 can include an electrical guiding medium (e.g., electrical wiring), an
optical and/or light
guiding medium (e.g., fiber optic cable), a hydraulic power medium (e.g., a
high pressure
tube or a hydraulic hose), a data conductor, and/or a pneumatic medium (e.g.,
high pressure
tubing or hose).
[0055] The disclosed energy conductors 62 can be oriented in at least a
partially helical
direction relative to a longitudinal 17 axis of the spoolable tube 10, and/or
in an axial
direction relative to the longitudinal axis 17 of the spoolable tube 10.
[0056] A hydraulic control line embodiment of the energy conductor 62 can
be either
formed of a metal, composite, and/or a polymeric material.
[0057] In one embodiment, several energy conductors 62 can power a machine
operably
coupled to the coiled spoolable tube 10. For instance, a spoolable tube 10 can
include three
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electrical energy conductors that provide a primary line 62, a secondary line
62, and a
tertiary line 62 for electrically powering a machine using a three-phase power
system. As
provided previously herein, the spoolable tube 10 can also include internal
pressure barriers
12 for transmitting fluids along the length of the tube 10. In some
embodiments, the fittings
of system 100 may also include a connection for an energy conductor, for
example, to
receive a energy conductor that forms part of a spoolable tube.
[0058] System 100 may also include a means for measuring the pressure of a
first fluid
being transported, for example, within a first passage defined by an inner
layer of a
spoolable tube, and an means for measuring the pressure of a second fluid
being transported,
for example, within an annular space between an inner and outer layer. Such
means for
measuring different pressure may include one or more devices. Such devices may
include a
manometer, a device that includes a piezoelectric sensor, a Bourden gauge, or
a variable
inducting diaphragm.
[0059] The pipe systems disclosed herein may also include leak detection
means or
fittings. Such leak detection means, as known to those skilled in the art, may
be positioned
along the spoolable pipe, positioned between the inner and outer layer of such
spoolable
pipe, or within fittings disposed on the axial ends.
[0060] Unless otherwise stated, use of the word "substantially" can be
construed to
include a precise relationship, condition, arrangement, orientation, and/or
other
characteristic, and deviations thereof as understood by one of ordinary skill
in the art, to the
extent that such deviations do not materially affect the disclosed methods and
systems.
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100611 Throughout the entirety of the present disclosure, use of the
articles "a" or "an" to
modify a noun can be understood to be used for convenience and to include one,
or more
than one of the modified noun, unless otherwise specifically stated.
[0062] Elements, components, modules, and/or parts thereof that are
described and/or
otherwise portrayed through the figures to communicate with, be associated
with, and/or be
based on, something else, can be understood to so communicate, be associated
with, and or
be based on in a direct and/or indirect manner, unless otherwise stipulated
herein.
[0063] It should be understood that alternative embodiments, and/or
materials used in
the construction of embodiments, or alternative embodiments, are applicable to
all other
embodiments described herein.
[0064] Although the methods and systems have been described relative to a
specific
embodiment thereof, they are not so limited. Many modifications and variations
may
become apparent in light of the above teachings. Many additional changes in
the details,
materials, and arrangement of parts, herein described and illustrated, can be
made by those
skilled in the art. Accordingly, it will be understood that the following
claims are not to be
limited to the embodiments disclosed herein, can include practices otherwise
than
specifically described, and are to be interpreted as broadly as allowed under
the law.
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