Note: Descriptions are shown in the official language in which they were submitted.
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Device for uncoupling a plug from a pulling head
FIELD OF THE INVENTION
[0001] The present invention relates to an auxiliary device for uncoupling a
plug from
a pipe pulling head, more specifically for uncoupling a plug from a pipe
pulling head in
cases in which the pipe is suspected to be under pressure.
BACKGROUND OF THE INVENTION
[0002] Pulling heads are elements that are commonly used, for example, in
lifting or
transporting flexible lines on offshore oil rigs. These elements are connected
to the
upper end of a flexible line, also called a riser, in order to enable it to be
lifted or
transported and for the end thereof to be sealed.
[0003]
In addition, besides enabling the lifting and transporting of a riser, the
pulling
head also prevents leakage of the internal contents thereof, since the riser
end is
completely isolated from the outside.
[0004] However, at the moment at which the pulling head is disconnected from a
riser, it is common for the riser to contain pressurized fluids inside, which
may cause
environmental accidents or operator mishaps when the pulling head is uncoupled
from
the riser, endangering the life of the operators responsible for this step.
[0005] In order to provide a form of depressurization of the riser prior to
removal of
the pulling head, the riser is provided with an element known as a plug. A
plug is a
threadable element that is provided in the pulling head which, when
disconnected from
the pulling head, provides an opening that connects the inside of the riser to
the outside.
Through this opening, it is possible to connect a drain hose in order to drain
gases or
liquids from inside the riser.
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[0006] However, even with the adoption of a pulling head plug, risks to the
operator
still exist. In situations where the riser contains pressurized gases in its
interior, the
force exerted on the plug may be such that, when unscrewed, the plug may be
expelled
at high speeds, which can cause serious injury to the operators responsible
for this
service.
[0007] In addition, contact with these gases may cause operator intoxication,
not to
mention the risk of explosion or fire, given that these fluids are often
flammable.
[0008] Similarly, environmental damage is not entirely remedied through the
mere
adoption of the plug, since unscrewing the plug causes a significant portion
of the gases
inside the riser to be expelled before the optional drain hose is connected to
the hole
into which the plug would be inserted.
[0009] However, nothing in the prior art is disclosed to circumvent such a
problem, as
becomes evident from the documents presented below.
[0010] EP2808608A1 discloses an end fitting for a tubular member 1, possibly a
pulling head, comprising a threaded elongate member, described as a threaded
pin,
that connects to an expandable member.
[0011] When the threaded pin is screwed in, the expandable element is
compressed,
causing it to expand and thereby locking and sealing the pipe with the pulling
head.
However, that document makes no reference to a device for removing the
threaded
element that is aimed at assisting in the circulation of fluids and/or
pressure that may be
contained within the pipe.
[0012] US7396060B2 discloses a pile pulling device that is secured to the end
of a
pipe through the action of a wedge. The device of that document comprises a
shaft, a
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housing upon the shaft, one or more wedges, a cone, nuts, eye nuts, 0 rings,
and a
sleeve, all arranged coaxially.
[0013] Nevertheless, even though document US7396060B2 describes a pipe pulling
device, it remains completely silent with respect to a device for removing the
threaded
element that is aimed at assisting in the circulation of fluids and/or
pressure that may be
contained within the pipe.
[0014] On the other hand, KR2007044886A discloses a pulling head device in
which
a pulling head unit and a strap element (band) are coupled by fastening
members in
such a way that the pulling head does not easily disengage from the pipe when
the
pulling head is pulled.
[0015] However, even though that document does describe a pipe pulling device,
it
remains completely silent with respect to a device for removing the threaded
element
(plug) that is aimed at assisting in the safe circulation of fluids and/or
pressure that may
be contained within the pipe.
[0016] As can be seen from the documents presented, the current state of art
lacks a
device for the safe removal of a plug from a pulling head so as to optionally
assist in the
circulation of fluid and/or pressure that may be contained in the interior of
the pipe.
SUMMARY OF THE INVENTION
[0017] It is the primary object of the present invention to provide a device
for safely
uncoupling a plug, as well as for optionally identifying and/or measuring the
presence of
pressure and flow within the pipe, directing this flow to a safe area.
[0018] In order to achieve this object, the present invention provides a
device for
uncoupling a plug from a pulling head comprising a main body which, in turn,
comprises
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an isolation chamber that is formed by an isolating wall, the isolation
chamber
comprising an element for uncoupling the plug from a pulling head, and a
coupling
element that is designed to keep an outer edge of the isolating wall in
contact with a
surface of the pulling head so as to maintain the isolation chamber isolated
from the
external environment.
BRIEF DESCRIPTION OF THE FIGURES
[0019] The detailed description presented below makes reference to the
enclosed
figures and their respective reference numbers, representing the embodiments
of the
present invention.
[0020] Fig. 1 shows a view of an optional embodiment of a device for
uncoupling a
plug from a pulling head while also showing a pulling head and a plug in an
exploded
view.
[0021] Fig. 2 shows a view of the assembly that is illustrated in Fig. 1 in an
assembled configuration.
[0022] Fig. 3 shows a cross-sectional view of the embodiment illustrated in
Fig. 2.
[0023] Fig. 4 shows detail 4A that is highlighted in Fig. 3, but in a
perpendicular
section.
[0024] Fig. 5 shows an isolated perspective view of a particular configuration
of a
device for uncoupling a plug from a pulling head.
[0025] Fig. 6 shows a cross-sectional view of a device for uncoupling a plug
from a
pulling head illustrated in Fig. 5.
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[0026] Fig. 7 shows a cross-sectional view of a second optional embodiment of
a
device according to the present invention for uncoupling a plug from a pulling
head.
[0027] Fig. 8 shows detail 7A that is highlighted in Fig. 7.
[0028] Fig. 9 shows an isolated perspective view of the particular
configuration of a
device for uncoupling a plug from a pulling head.
[0029] Fig. 10 shows a cross-sectional front view of a device for uncoupling a
plug
from a pulling head illustrated in Fig. 9.
[0030] Fig. 11 shows a cross-sectional side view of a device for uncoupling a
plug
from a pulling head illustrated in Fig. 9.
DETAILED DESCRIPTION OF THE INVENTION
[0031] First of all, it should be emphasized that the following description
will
commence from a preferred embodiment of the invention as applied to a device
for
uncoupling a plug from a pulling head. As will be clear to any person skilled
in the art,
however, the invention is not limited to that particular embodiment.
[0032] In order to remedy the abovementioned problems of the prior art, the
invention
provides a device for uncoupling a plug from a pulling head comprising a main
body
which, in turn, comprises an isolation chamber that is formed by an isolating
wall, the
isolation chamber comprising an element for uncoupling the plug from a pulling
head,
and a coupling element that is designed to keep an outer edge of the isolating
wall in
contact with a surface of the pulling head so as to maintain the isolation
chamber
isolated from the external environment. Optionally, the isolating wall has a
cylindrical
shape.
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[0033] That way, the tool is positioned on a surface of a pulling head such
that the
plug is circumscribed at the outer edge of the isolating wall, thereby forming
an isolation
chamber in which the plug is positioned within the interior thereof. The plug
uncoupling
element is actuated only after positioning of the device, so if there are
pressurized fluids
inside the riser on which the pulling head is positioned, that fluid is
contained inside the
isolation chamber when the plug is uncoupled.
[0034] Likewise, the plug can be safely uncoupled even if there are
pressurized flows
within the riser on which the pulling head is positioned, since the isolation
chamber also
provides a physical barrier to prevent the plug from being thrown at high
speeds when
completely uncoupled.
[0035] Optionally, the isolating wall can comprise at least one fluidic
communication
pipe that is in communication with the interior of the isolation chamber. The
fluidic
communication pipe can be used to drain any fluids that may be present inside
the riser
and convey them to the isolation chamber upon uncoupling of the plug. In
alternative
embodiments, the pipe can be used to insert a pressurized fluid into the
isolation
chamber, thereby pressurizing the isolation chamber in order to prevent
leakage of
fluids from within the riser. The pressurization of the isolation chamber
could thus serve
as a tightness test. For this purpose, the pressure that is applied to the
isolation
chamber is optionally approximately 10% greater than the expected maximum
pressure
inside the riser.
[0036] It should be emphasized that the device described thus far can be
configured
to withstand different pressure levels. Testing has revealed that, for many
applications,
the tool must withstand pressures of up to 5000 psi (345 bar); however, the
tool can be
designed to withstand more or less pressure according to the requirements of
the
application.
[0037] In other alternative embodiments, the same fluidic communication pipe
can be
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initially used to insert a pressurized fluid into the isolation chamber in
order to prevent
fluid leakage from the riser and, after uncoupling, to drain any fluids
contained inside the
riser into the isolation chamber.
[0038] Another alternative embodiment makes a provision that the isolating
wall can
comprise two fluidic communication pipes that are in communication with the
interior of
the isolation chamber. In this embodiment, a first fluidic communication pipe
is designed
to inject a pressurized fluid into the isolation chamber, and a second fluidic
communication pipe is designed to drain a fluid out of the isolation chamber.
[0039] In any of the embodiments described above, fluid flowing out of the
isolation
chamber through the fluidic communication pipe may be intended for future
storage
and/or treatment in accordance with environmental rules and regulations at the
site of
application. In addition, a valve, or manifold, can be optionally used to
perform flow
control and fluid pressure measurements of the described system.
[0040] Thus, as has been described so far, it is clear that the device of the
present
invention has a number of advantages not found in the prior art, such as
operator safety
when performing plug uncoupling, as the plug will not be expelled at high
speeds, as
well as the guarantee of environmental safety, since the fluids contained in
the riser are
kept inside the isolation chamber and safely drained afterwards.
[0041] Fig. 1 shows a view of an optional embodiment of a device for
uncoupling a
plug 8 from a pulling head while also showing a pulling head 9 and a plug 8 in
an
exploded view.
[0042] Fig. 2 shows a view of the assembly that is illustrated in Fig. 1 in
its assembled
configuration. Fig. 3 shows a cross-sectional view of the embodiment that is
illustrated
in Fig. 2 in which the operation of the invention can be observed as described
above.
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[0043] Accordingly, the plug uncoupling device is positioned so as to be in
contact
with a pulling head 9, so that the outermost edge of the isolating wall 31 is
in contact
with the surface of the pulling head 9, so that the plug 8 is circumscribed at
this outer
edge of the isolating wall 31. The isolation chamber 32 is thus completely
isolated from
the external environment, so that when the plug 8 is uncoupled from the
pulling head 9,
the fluids contained within the riser and drained through a channel 92 of the
pulling
head 9 are contained in the isolation chamber 32 without leaking into the
environment.
[0044] The description given in the previous paragraph is made even clearer
with the
aid of Fig. 4, which shows the detail 4A that is highlighted in Fig. 3, but in
a
perpendicular section. In that figure, it can be seen that a sealing element 5
is optionally
used to seal the contact between the outermost edge of the isolating wall 31
and the
surface of the pulling head 9.
[0045] In the section shown, it can also be seen more clearly that the
isolating wall 31
optionally comprises two fluidic communication pipes 33 that are in
communication with
the interior of the isolation chamber 32. These fluidic communication pipes 33
are used
to drain any fluids that may be present inside the riser and convey them to
the isolation
chamber 32 upon uncoupling of the plug 8, as described previously. Preferably,
a first
fluidic communication pipe 33 is designed to inject a pressurized fluid into
the isolation
chamber 32, and a second fluidic communication pipe 33 is designed to drain a
fluid out
of the isolation chamber 32.
[0046] Fig. 5 shows an isolated perspective view of a particular configuration
of a
device 1 for uncoupling a plug from a pulling head. Fig. 6 shows a cross-
sectional view
of a device for uncoupling a plug from a pulling head illustrated in Fig. 5,
in which the
uncoupling element 21 is connected to a plug 8. In these figures, it can be
seen that the
optional configuration of the device for uncoupling a plug from a pulling head
is such
that the main body 1 is formed by an inner cylindrical body 2 and an outer
cylindrical
body 3 that are concentric with one another, the inner and outer cylindrical
bodies 2 and
,
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3, respectively, being designed to rotate relative to each other. In this
embodiment, the
inner cylindrical body 2 comprises the uncoupling element 21 of the plug 8 at
a first end,
and the outer cylindrical body 3 comprises the isolating wall 31 at a first
end.
[0047] In this configuration, in order for the seal of the isolation chamber
32 to be
maintained, at least one seal ring 51 is also provided between the inner
cylindrical body
2 and the outer cylindrical body 3. Preferably, a plurality of seal rings 51
are provided in
order to ensure proper functioning of the isolation chamber 32.
[0048] In addition, in order to enable better positioning and removal of the
plug
uncoupling element 21 from the plug 8 itself, at least a portion of the inner
cylindrical
body 2 comprises means for moving longitudinally with respect to its axis of
rotation.
[0049] Also optionally, the coupling element 4 is a cylindrical element that
is
concentric with the main body 1 and designed to rotate relative thereto.
According to the
illustrated embodiment, the device of the present invention thus comprises
three
cylindrical and concentric elements: coupling element 4; inner cylindrical
body 2; and
outer cylindrical body 3, with the coupling element 4 being designed to rotate
relative to
the outer cylindrical body 3, and with the outer cylindrical body 3 being
designed to
rotate relative to the inner cylindrical body 2.
[0050] Also optionally, the coupling element 4 is connected to the main body 1
by
means of a screw thread, the coupling element 4 comprising a stop 40 that is
designed
to abut against a pin 11 that is attached to an eye 91 of the pulling head 9.
Thus,
rotation of the coupling element 4 produces a longitudinal displacement
between it and
the outer cylindrical body 3, so that the isolation chamber 32 of the outer
cylindrical
body 3 approaches the surface of the pulling head 9 until its outermost edge
(or sealing
element 5) is pressed against the surface of the pulling head 9, effecting the
coupling of
the tool.
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[0051] The coupling element 4 can optionally comprise an actuating lever 42 to
facilitate rotation and consequent coupling thereof with the pulling head 9.
The actuating
lever 42 can be attached to the coupling element 4 itself, or it can be
temporarily
connected for use only during coupling and removal for ease of handling. To
this end,
the actuating lever 42 and the coupling element 4 can have a tight fit in any
geometric
shape that does not allow sliding between the elements when the tool is
turned.
[0052] After the described coupling, the inner cylindrical body 2 is moved
vertically so
that the plug uncoupling element 21 contacts the plug 8, thus enabling it to
be
uncoupled.
[0053] As is known from the prior art, the vast majority of plugs 8 are
coupled with the
pulling head 9 by means of a screw thread, making it possible for the plug
uncoupling
element 21 of the present invention to unscrew the plug 8. For this purpose,
the
uncoupling element 21 must comprise means for connecting to the plug 8, so
that when
it is turned it will execute the removal of the plug 8. Preferably, the
uncoupling element
21 has a hexagonal shape that fits into a hexagonal hole in the plug 8.
However, it
should be emphasized that the shape of the uncoupling element 21 is any shape
that
fits the shape of the plug hole 8.
[0054] To this end, the present invention provides for adoption of any of the
following
configurations: only the uncoupling element 21 is rotated relative to the
isolating wall 31;
a portion of the inner cylindrical body 2 is rotated relative to the isolating
wall 31; and/or
the entire inner cylindrical body 2 is rotated relative to the isolating wall
31. As
illustrated, an actuator 23 that is designed to actuate the uncoupling element
21 is
optionally provided, in which case the actuator 23 is an Allen key that is
connected to
one end of the inner cylindrical body 2, that end being situated opposite the
end
comprising the uncoupling element 21.
[0055] Optionally, the inner cylindrical body 2 can be manufactured in two
parts that
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are joined by a coupling 22, so that the coupling is fixed to each part by
fastening
elements 221, preferably screws. This configuration can be adopted in cases in
which
there are length limits for the manufacture of the shaft. Optionally, the
shaft is
manufactured by electrical discharge machining.
[0056] Also optionally, the invention provides for the use of at least one
locking
element 7 for use after the final coupling of the device. The locking element
7 has the
function of preventing relative turns between at least one of: the main body 1
and the
coupling element 4; and the inner cylindrical element 2 and the outer
cylindrical element
3. Thus, once the device is secured, the at least one locking element prevents
it from
disconnecting, which could cause accidents and/or leaks. Optionally, the
locking
element is a screw.
[0057] Fig. 7 shows a cross-sectional view of a second optional embodiment of
a
device according to the present invention for uncoupling a plug from a pulling
head. Fig.
8 shows detail 7A that is highlighted in Fig. 7.
[0058] As can be seen from Figs. 8 and 9, the pulling head 9 to which the plug
uncoupling device is being applied has smaller dimensions than the one
previously
presented, for which reason the device comprises an adapter element 24 that is
connected in a sealing manner to the outer edge of the isolating wall 31. In
this specific
embodiment, the adapter element 24 has a curvilinear shape in order to fit
more closely
against the surface of the pulling head 9. This makes it possible for the same
device to
be used on pulling heads of different sizes, which demonstrates the
versatility of the
disclosed device.
[0059] The adapter element 24 can be made of metal or of any polymeric
material
such as rubber or silicone. In addition, a sealant can be provided between the
adapter
element 24 and the isolating wall 31 in order to ensure that no fluid leaks
from the
isolation chamber 32.
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[0060] Fig. 9 shows an isolated perspective view of the particular
configuration of a
device for uncoupling a plug from a pulling head illustrated in Fig. 8. Fig.
10 shows a
cross-sectional front view of a device for uncoupling a plug from a pulling
head
illustrated in Fig. 9, and Fig. 11 shows a cross-sectional side view of a
device for
uncoupling a plug from a pulling head illustrated in Fig. 9.
[0061]
In the optional configuration illustrated in Figs. 9, 10, and 11, the adapter
element 24 comprises at least one sealing element 5, 5' at the contact between
the
adapter 24 and the surface of the pulling head 9. In a preferred embodiment,
two
sealing elements are used, with a more rigid first sealing element 5 being
attached to
the adapter 24, and with a more flexible second sealing element 5' being
positioned
between the first sealing element 5 and the surface of the pulling head 9.
[0062] It should be noted that, although a convex-shaped adapter element 24 is
described, such an element can have various shapes, including a concave shape.
As
will readily be understood by any person skilled in the art, the shape of the
adapter
element 24 will vary according to the surface profile of the pulling head 9 to
which the
device of the present invention is to be applied.
[0063] It should be emphasized that the embodiment presented in Figs. 8, 9,
10, and
11 also optionally comprises a number of the features described above,
according to
which the isolation chamber 32 is completely isolated from the external
environment: so
that when the plug 8 is uncoupled from the pulling head 9, the fluids
contained within
the riser and drained through a channel 92 of the pulling head 9 are contained
in the
isolation chamber 32 without leaking into the environment.
[0064] In the embodiment presented here, it can also be seen that the
isolating wall
31 optionally comprises two fluidic communication pipes 33 that are in
communication
with the interior of the isolation chamber 32. As described previously, these
fluidic
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communication pipes 33 are used to drain any fluids that may be present inside
the riser
and convey them to the isolation chamber 32 upon uncoupling of the plug 8.
[0065] In the embodiment shown in Figs. 8, 9, 10, and 11, it can also be seen
that the
main body 1 is optionally formed by an inner cylindrical body 2 and an outer
cylindrical
body 3 that are concentric with one another, with the inner and outer
cylindrical bodies
being designed to rotate with each other, the inner cylindrical body 2
comprising the
uncoupling element 21 of the plug at a first end, and the outer cylindrical
body 3
comprising the isolating wall 31 at a first end, with at least one sealing
ring 51 being
provided between the inner cylindrical body 2 and the outer cylindrical body
3.
[0066] Also optionally, the coupling element 4 is a cylindrical element that
is
concentric with the main body 1 and designed to rotate relative thereto.
According to the
illustrated embodiment, the device of the present invention thus comprises
three
cylindrical and concentric elements: coupling element 4; inner cylindrical
body; and
outer cylindrical body 3, with the coupling element 4 being designed to rotate
relative to
the outer cylindrical body 3, and with the outer cylindrical body 3 being
designed to
rotate relative to the inner cylindrical body 2.
[0067] Optionally, the coupling element 4 is connected to the main body 1 by
means
of a screw thread, the coupling element 4 comprising a stop 40 that is
designed to abut
against a pin 11 that is attached to an eye 91 of the pulling head 9. Thus,
rotation of the
coupling element 4 produces a longitudinal displacement between it and the
outer
cylindrical body 3, so that the isolation chamber 32 of the outer cylindrical
body 3
approaches the surface of the pulling head 9 until the adapter element 24 is
pressed
against the surface of the pulling head 9, effecting the coupling of the tool.
[0068] Although not shown, the present invention also provides a configuration
in
which the outermost edge of the isolating wall 31 has a curvilinear shape in
order to fit
the pulling head 9 as illustrated in Figs. 8, 9, 10, and 11. However, the use
of an
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adapter element 2, as described above is preferred, since it is thus possible
to use the
same device to remove the plug 8 from different pulling heads, with the
adapter element
24 being used when necessary.
[0069] After the described coupling, the inner cylindrical body 2 is moved
vertically so
that the plug decoupling element 21 contacts the plug 8, thus enabling it to
be
uncoupled.
