U.S. patent application number 14/366222 was filed with the patent office on 2014-11-06 for well completion arrangement and a method for preparing a well for abandonment.
This patent application is currently assigned to WTW Solutions AS. The applicant listed for this patent is WTW Solutions AS. Invention is credited to Bard Martin Tinnen.
Application Number | 20140326470 14/366222 |
Document ID | / |
Family ID | 48668885 |
Filed Date | 2014-11-06 |
United States Patent
Application |
20140326470 |
Kind Code |
A1 |
Tinnen; Bard Martin |
November 6, 2014 |
Well Completion Arrangement and a Method for Preparing a Well for
Abandonment
Abstract
A well completion arrangement and method is for removing at
least a portion of a line running in an annulus between a tubing
and a casing in a well. The arrangement comprises at least two
clamping means spaced apart in the longitudinal direction of the
tubing and fixed thereto, the clamping means being configured for
fixing the line with respect to tubing, a splitting means for
releasing the line from the interval defined by at least an upper
clamping means and a lower clamping means of the at least two
clamping means, a line manipulator apparatus for activating said
release of the line, and a line retrieval apparatus for displacing
into the tubing the portion of the line from said interval, thereby
removing the line from the annulus.
Inventors: |
Tinnen; Bard Martin;
(Stavanger, NO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
WTW Solutions AS |
Stavanger |
|
NO |
|
|
Assignee: |
WTW Solutions AS
Stavanger
NO
|
Family ID: |
48668885 |
Appl. No.: |
14/366222 |
Filed: |
December 11, 2012 |
PCT Filed: |
December 11, 2012 |
PCT NO: |
PCT/NO2012/050246 |
371 Date: |
June 17, 2014 |
Current U.S.
Class: |
166/385 ;
166/241.5 |
Current CPC
Class: |
E21B 33/134 20130101;
E21B 17/026 20130101; E21B 29/04 20130101 |
Class at
Publication: |
166/385 ;
166/241.5 |
International
Class: |
E21B 29/04 20060101
E21B029/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 21, 2011 |
NO |
20111760 |
Claims
1. A well completion arrangement for removing at least a portion of
a line running in an annulus between a tubing and a casing in a
well, the arrangement comprising: at least two clamping means
spaced apart in the longitudinal direction of the tubing and fixed
thereto, the clamping means being configured for fixing the line
with respect to tubing; splitting means for releasing the line from
the interval defined by at least an upper clamping means and a
lower clamping means of the at least two clamping means; a line
manipulator apparatus, for activating said release of the line; a
line retrieval apparatus for displacing into the tubing the portion
of the line from said interval, thereby removing the line from the
annulus.
2. The well completion apparatus according to claim 1, wherein the
clamping means constitutes a portion of the tubing connecting two
tubing joints (401), or associated crossover piping towards the
tubing.
3. The well completion arrangement according to claim 1, wherein
the arrangement is provided with an allocation means for
controlling the position of at least the manipulator apparatus
(901, 2101) with respect to the holding means.
4. The well completion arrangement according to claim 1, wherein
the line manipulator apparatus comprises the line retrieval
apparatus.
5. The well completion arrangement according to claim 1, wherein
the splitting means is provided in at least one of the clamping
means.
6. The well completion arrangement according to claim 1, wherein
the splitting means is provided in the manipulator apparatus.
7. The well completion arrangement according to claim 1, wherein
the splitting means is adapted to cut through a portion of the
clamping means.
8. The well completion arrangement according to claim 1, wherein
the line manipulator is further provided with gripping means
adapted for engaging a profile of the clamping means, the profile
being arranged adjacent of the holding means.
9. The well completion arrangement according to claim 1, wherein
the retrieval apparatus is at least one of a flow and pressure
inducing apparatus arranged for displacing the line from the
outside to the inside of the tubing.
10. The well completion arrangement according to claim 9, wherein
at least one of the flow and pressure inducing apparatus is a pump
located on the surface of the well.
11. A method of preparing a well for abandonment, the method
comprising: incorporating at least two spaced apart clamping means
in a tubing during completion of the well, the clamping means being
provided with a holding means for fixing a line with respect to the
clamping means, the line running in an annulus between the tubing
and a casing; providing splitting means for releasing the line at
least at an upper clamping means and at a lower clamping means of
the at least two clamping means, providing an apparatus for
inducing said release of the line; and providing an apparatus for
displacing into the tubing the portion of the line from the
interval defined by at least the upper clamping means and at the
lower clamping means of the at least two clamping means.
Description
[0001] This invention relates to controlled splitting, release and
removal of at least one line from a defined section of an annulus
between a tubing and a casing of a well related to the production
of hydrocarbons. More specifically the present invention relates to
a well completion arrangement for removing at least a portion of a
line running in an annulus between a tubing and a casing in a well
and a method for preparing a well for abandonment.
[0002] The main objective with the present invention is to provide
an arrangement and a method for controlled removal of at least a
section of at least one line in a well.
[0003] In this document the term line is meant to be any line
running in an annulus between a tubing and a casing. Such a line
may be a control line, a communication line, a chemical injection
line and similar. The line may be used to transmit electric or
fiber-optic signals, electric power, hydraulic fluid pressure,
scale inhibiting chemicals and similar. For the sake of simplicity
the line is commonly referred to as control line, but can be any
line mentioned above.
[0004] When abandoning a well in an oil/gas field and related
wells, the shutting down of the well has to be conducted according
to relevant regulatory practices. The general term for such
operations is "plug and abandonment". The regulatory practices
define the number and nature of barriers that need to be
permanently established between the hydrocarbon carrying formation
and the surface. Moreover, the practices define what equipment that
can be left permanently in the well and what equipment that has to
be removed.
[0005] Traditionally, plug and abandonment operations have been
conducted using rigs or tailor made jack systems, cutting the
tubing and the control line deep in the well, and pulling
everything out to the surface. Subsequent to this, the well is
cemented, and the top sections of the casing and conductors are cut
and removed.
[0006] For subsea wells, the use of rigs for plug and abandonment
operations becomes extremely expensive. Jack systems for similar
operations does not currently exist, but may be developed in the
future. Anyhow, both rig and jack operations would be very
expensive to use for plugging and abandoning subsea wells.
[0007] The regulations related to plug and abandonment work do
allow for the tubing to be left as part of the permanently cemented
equipment left in the well. However, control lines used to
communicate and/or operate downhole equipment such as sensors and
flow control devices cannot be left permanently in the well, as
they represent a potential for future leakage paths through the
cement. The control lines are typically clamped to the outside of
the production tubing, and in most cases there is no practical way
of removing the control lines without cutting and pulling the
tubing itself.
[0008] The invention has as its object to remedy or at least reduce
one or more drawbacks of the prior art.
[0009] The object is achieved through features as specified in the
description below and in the subsequent Claims.
[0010] In this document splitting will mean any kind of dividing of
the line, such as cutting, clipping, pulling apart, such as pulling
apart over a pre-created weakpoint or coupling in the line,
squeezing apart and disconnecting by means of operating line
couplings designed for this purpose.
[0011] In a first aspect of the present invention there is provided
a well completion arrangement for removing at least a portion of a
line running in an annulus between a tubing and a casing in a well,
wherein the arrangement comprising: [0012] at least two clamping
means spaced apart in the longitudinal direction of the tubing and
fixed thereto, the clamping means being configured for fixing the
line with respect to tubing; [0013] splitting means for releasing
the line from the interval defined by at least an upper clamping
means and a lower clamping means of the at least two clamping
means; [0014] a line manipulator apparatus for activating said
release of the line; [0015] a line retrieval apparatus for
displacing into the tubing the portion of the line from said
interval, thereby removing the line from the annulus.
[0016] The clamping means may constitute a portion of the tubing
connecting two tubing joints, or associated crossover piping
towards the tubing.
[0017] The arrangement may be provided with an allocation means for
controlling the position of at least the manipulator apparatus with
respect to the holding means.
[0018] The line manipulator apparatus may comprise the line
retrieval apparatus.
[0019] The splitting means may be provided in at least one of the
clamping means.
[0020] Alternatively, the splitting means may be provided in the
manipulator apparatus.
[0021] Thus, the splitting means may be adapted to cut through a
portion of the clamping means.
[0022] The line manipulator may further be provided with gripping
means adapted for engaging a profile of the clamping means. The
profile may be arranged adjacent of the holding means.
[0023] The retrieval apparatus may be a flow and/or pressure
inducing apparatus arranged for displacing the line from the
outside to the inside of the tubing. In one embodiment of the
present invention the flow and/or pressure inducing apparatus is a
pump located on the surface of the well.
[0024] In a second aspect of the present invention there is
provided a method of preparing a well for abandonment, the method
comprising the steps of: [0025] incorporating at least two spaced
apart clamping means in a tubing during completion of the well, the
clamping means being provided with a holding means for fixing a
line with respect to the clamping means, the line running in an
annulus between the tubing and a casing; [0026] providing splitting
means for releasing the line at least at an upper clamping means
and at a lower clamping means of the at least two clamping means;
[0027] providing an apparatus for inducing said release of the
line; and [0028] providing an apparatus for displacing into the
tubing the portion of the line from the interval defined by at
least the upper clamping means and at the lower clamping means of
the at least two clamping means.
[0029] The following describes a non-limiting example of a
preferred embodiment illustrated in the accompanying drawings, in
which:
[0030] FIG. 1 is a generic sectional view of a well for the
production of hydrocarbons;
[0031] FIG. 2 illustrates a prior art plug and abandonment
technique;
[0032] FIG. 3 illustrates a desired scenario for plugging and
abandonment, which is sought by means of the invention described
herein;
[0033] FIG. 4 illustrates prior art attachment techniques for
securing a control line to production tubing;
[0034] FIG. 5 illustrates a generic well completion according the
present invention;
[0035] FIG. 6 illustrates the same well completion as shown in FIG.
5, but where the control line has been removed;
[0036] FIG. 7 illustrates the completion from FIGS. 5-6 after the
well has been cemented;
[0037] FIG. 8a illustrates in a sectional view one embodiment of a
bottom clamp further to the invention herein;
[0038] FIG. 8b illustrates a side view of FIG. 8a seen from right
to left;
[0039] FIG. 9a illustrates the bottom clamp in FIG. 8a where a
wireline manipulation tool is used to create a cut and perform an
initial release operation of the control line;
[0040] FIG. 9b illustrates a side view of FIG. 9a seen from right
to left;
[0041] FIG. 10a illustrates in a sectional view an embodiment of an
intermediate clamp further to the invention herein;
[0042] FIG. 10b illustrates a side view of FIG. 10a seen from right
to left;
[0043] FIG. 11a illustrates the intermediate clamp of FIG. 10a, and
a wireline manipulation tool used to perform a release operation of
the control line;
[0044] FIG. 11b illustrates a side view of FIG. 11a seen from right
to left;
[0045] FIG. 12a illustrates a sectional view of one embodiment of a
top clamp further to the invention herein;
[0046] FIG. 12b illustrates a side view of FIG. 12a seen from right
to left;
[0047] FIG. 13a illustrates the top clamp of FIG. 12a, and a
wireline manipulation tool used to perform a cut and release
operation of the control line;
[0048] FIG. 13b illustrates a side view of FIG. 13a seen from right
to left;
[0049] FIG. 14a illustrates the top clamp of FIGS. 12a-13a, after
the control line has been cut and released, and shows the initial
stage of the control line removal operation;
[0050] FIG. 14b illustrates a side view of FIG. 14a seen from right
to left;
[0051] FIG. 15a illustrates a sectional view of a top clamp in
another embodiment, and a wireline manipulation tool used to
perform a cut and release operation of the control line;
[0052] FIG. 15b illustrates a side view of FIG. 15a seen from right
to left;
[0053] FIG. 16a illustrates the top clamp of FIG. 15a, after the
control line has been cut and released, and shows the initial stage
of the control line removal operation;
[0054] FIG. 16b illustrates a side view of FIG. 16a seen from right
to left;
[0055] FIG. 17a illustrates a sectional view of another embodiment
of a top clamp further to the invention herein;
[0056] FIG. 17b illustrates a side view of FIG. 17a seen from right
to left;
[0057] FIG. 18a illustrates the top clamp of FIG. 17a, and a
wireline manipulation tool used to perform a cut and release
operation of the control line;
[0058] FIG. 18b illustrates a side view of FIG. 17a seen from right
to left;
[0059] FIG. 19a illustrates the top clamp of FIGS. 17a-18a, after
the control line has been cut and released, and shows the initial
stage of the control line removal operation;
[0060] FIG. 19b illustrates a side view of FIG. 19a seen from right
to left;
[0061] FIG. 20a illustrates in a sectional view another embodiment
of a top clamp further to the invention herein;
[0062] FIG. 20b illustrates a side view of FIG. 20a seen from right
to left;
[0063] FIG. 21a illustrates the top clamp of FIG. 20a, and a
wireline manipulation tool in engagement with it to perform a cut
and release operation of the control line;
[0064] FIG. 21b illustrates a side view of FIG. 21a seen from right
to left;
[0065] FIG. 22a illustrates the top clamp of FIGS. 20a-21a, after
the control line has been cut and released, and the system being
ready for the control line removal operation;
[0066] FIG. 22b illustrates a side view of FIG. 22a seen from right
to left;
[0067] FIG. 23a illustrates in a smaller scale a sectional view of
a larger well schematic, and the well status upon completing the
manipulation step illustrated in FIG. 22a;
[0068] FIG. 23b illustrates in a larger scale a detail of FIG.
23a;
[0069] FIG. 24a illustrates a first step of removing the control
line based on a scenario as illustrated in FIG. 23a;
[0070] FIG. 24b illustrates in a larger scale a detail of FIG.
24a;
[0071] FIG. 25a illustrates a second step of removing the control
line based on a scenario as illustrated in FIG. 23a;
[0072] FIG. 25b illustrates in a larger scale a detail of FIG.
25a;
[0073] FIG. 26a illustrates a sectional view of an alternative
arrangement for removing the control line based on a scenario as
illustrated in FIG. 23a;
[0074] FIG. 26b illustrates in a larger scale a detail of FIG. 26a;
and
[0075] FIG. 27 illustrates a sectional view of an alternative
embodiment for removing the control line based on a scenario as
illustrated in FIG. 23a.
[0076] In this document positional specifications such as "upper"
and "lower", "bottom" and "top" or "horizontal" and "vertical"
refer to the position of the apparatus in the figures, which may
also be a natural, necessary or practical functional position.
[0077] In FIG. 1 a borehole 101 is provided with a casing 102 used
for preventing the borehole from collapsing during drilling and
subsequent production. In the lower section of the well, the casing
102 is cemented to the borehole 101, resulting in a section of what
is referred to as casing cement 103 herein; filling the annular
area between the casing 102 and the borehole 101. The casing cement
103 forms one of several required fluid barriers between the
underground, hydrocarbon carrying formation and the surface.
[0078] FIG. 1 illustrates a generic well completion wherein the
lower completion comprises a production liner 104, which is
cemented to the borehole using liner cement 105. The liner is open
towards the hydrocarbon reservoir via perforations 106. The design
and configuration of the production liner 104 may vary
significantly from what is illustrated herein, however this will be
appreciated by a person skilled in the art and not further
described herein. The production liner 104 is anchored to and forms
a seal towards the casing 102 by means of a liner hanger system
107.
[0079] The upper completion comprises a production tubing 108,
which is stung into the lower completion by means of a seal stinger
assembly 109. In the bottom section of the tubing 108, this is
terminated and forms a seal towards the casing 102 by means of a
production packer 110. In the top of the well, the tubing 108 is
terminated in the lower section of the wellhead 111.
[0080] In the lower section of the tubing 108, a permanent downhole
pressure and temperature gauge 112 is mounted. This is powered and
communicates to the surface by means of a control line 113.
[0081] In the top of the wellhead 111, an intervention bore 114 is
blocked by two crown plugs 115. On the side of the wellhead 111, a
flow line 116 is connected to a production bore 117.
[0082] The completion design may vary significantly from what is
shown in FIG. 1, and there are common completion components that
are not illustrated herein, such as a downhole safety valve. This
is done consciously in order to simplify the drawings, hence direct
the focus on the design and methods directly related to the
invention described herein. Such facts will be appreciated by a
person skilled in the art.
[0083] FIG. 2 illustrates relevant aspects in relation to prior art
techniques for permanent plugging and abandonment of wells. In
conjunction with such operations, heavy kill fluid is pumped into
the well, whereupon a deep-set mechanical barrier 118 is installed.
In conjunction with the killing of the well, holes 119 are punched
in the tubing 108 to allow for displacement to kill fluid both on
the inside and the outside of the tubing 108. As a next step,
further to current practice, the tubing 108 and control line 113 is
cut, normally right above the production packer 110, the cut being
illustrated by the line A-A'. Then, the tubing 108 and control line
113 is hauled out of the well using traditional casing/tubing
handling equipment such as tongues and control line 108 winches, or
tailored jack based tubing retrieval systems on the surface.
[0084] The subsequent step in plugging and abandonment is the
installation of a cement retaining device 120, before a cement
column referred to as abandonment cement 121 is dumped on top of
the cement retainer 120. It is a common requirement that the height
of the abandonment cement 121 column must equal or exceed a
particular length L. In many cases, the length L equals 50 meters.
A final important requirement in this respect is that the
abandonment cement 121 must fully overlap with the casing cement
103 in order to provide for the required pressure barrier function
between the hydrocarbon carrying reservoir formation and the
surface.
[0085] In particular on fields developed by means of subsea well
solutions, plug and abandonment operations can become very
expensive, as the current practice requires a drilling rig to
perform the operation. An object of the present invention is to
remove the need for a drilling rig to plug and abandon wells.
[0086] FIG. 3 illustrates a hypothetical situation, further to a
scenario sought achieved by the invention described herein. In the
scenario illustrated in FIG. 3 the tubing is not pulled out of the
well. Instead, the cement is pumped down the inside or bore of the
tubing 108, through the holes 119 and up the annulus between the
tubing 108 and the casing 102 as illustrated in FIG. 3. The result
is a column of abandonment cement 121 that fills both on the inside
and the annulus on the outside of the tubing 108. Current
regulations allow for such a method to be used, leaving the
relevant section of tubing 108 encased by the abandonment cement
121. The only limitation is that the control line 113 cannot be
left inside along the permanent cement barrier. Current regulations
state that the control line 113 may form a future leak path; hence
it needs to be removed prior to installing the cement 121. There is
no current existing technique to remove control line 113 from the
annular area between the tubing 108 and the casing 102. In order to
avoid rig operations for performing the plug and abandonment work,
there is a need for an arrangement and a method for cutting and
removing a section of control line 113 from the interval of length
L as illustrated in FIG. 3.
[0087] FIG. 4 illustrates prior art technology for attaching the
control line 113 to the tubing 108. The main parts of the tubing
108 is made up of tubing joints 401 and collars 402. In normal
cases, each tubing joint is approximately 12 meters long. Common
practice for installing a control line 113 is to attach it to the
tubing 108 using one cable clamp 403 per collar 402. There are
several designs of cable clamps 403, the one illustrated herein
having bands 404 surrounding the tubing, the bands 404 being
located adjacent the shoulders of the collar 402. This prevents any
sliding of the clamps 403 along the tubing 108 during installation
in the well. The clamp 403 is commonly a hinged design, manually
installed when running the well completion. The clamps 403 are
mounted on the tubing 108 as illustrated, whereupon the control
line(s) is/are routed into grooves 405 of the clamp 403 prior to
closing this and tightening it up using torque bolts 406. As a part
of this process, the control line 113 gets squeezed towards the
tubing 108 via the main shoulders 407 of the clamp 403, hence
securing this from any sliding movement along the length of the
tubing 108. As per current practice, the removal of control line
113 from the annulus between the tubing 108 and the casing 102 is
difficult, as the orientation of the control line 113 is unknown;
the tubing 108 may be ex-centered inside the casing 102, the clamps
403 being made of very hard materials, difficult to cut etc.
Finally, in relation to cutting the tubing 108 and the control line
113, there are regulatory requirements not to cause any damage to
the casing 102, making a cutting, allocation and retrieval process
for the control line 113 difficult.
[0088] According to the present invention, a well is completed in a
different manner than what is performed today. More specifically,
sections of the well overlapping with the interval of length L in
FIG. 3, are proposed completed by means of cable clamping
arrangements having distinctive characteristic in order to
facilitate for releasing, accessing and removing the control line
113 over an interval that has an equal or exceeding overlap with
the interval of length L in FIG. 3.
[0089] FIG. 5 illustrates a preferred embodiment of the invention.
In the illustration clamping means comprising one top clamp 501,
two intermediate clamps 502, 502' and one bottom clamp 503 is
illustrated. An important functionality related to these clamps
501, 502, 502', 503 is to secure the line 113 to the tubing 108
during installation of the well completion and for the wells life.
Essential functionality characteristics in conjunction with the
plugging and abandonment of wells are: [0090] The ability to
perform a controlled splitting of the line 113 (typically done in
the top clamp 501, the bottom clamp 503 or both). [0091] The
ability to perform a controlled release of the line 113 (typically
done in the top clamp 501 and bottom clamp 503 in conjunction with
a splitting/cutting operation, and for some embodiments in the
intermediate clamps 502, 502' [0092] The ability to remove at least
a majority of the line 113 from an interval equal to or exceeding,
and overlapping with the interval L as described above--in a
controlled manner.
[0093] There are several conceptual ways of achieving the
above--some examples are described in relation to the subsequent
figures of this document.
[0094] In one embodiment of the invention, all of the control line
113 is removed in one go. For this embodiment, the intermediate
clamps 502, 502' are designed to allow for the controlled release
of the control line 113 from the tubing at these locations, without
cutting the control line 113.
[0095] In another embodiment, the control line 113 is removed
sequentially. In one associated embodiment the control line 113 is
removed in sections that for the most overlap with the length of
the associated tubing joints. In this case, the intermediate clamps
502, 502' may not be relevant to use. In one related embodiment the
top clamp 501 and bottom clamp 503 is merged into one uniform
design, providing for both the ability to split the relevant
section of control line 113 as well as removing this from the
interval of relevance.
[0096] It should be emphasized that the clamps 501, 502, 502', 503
described herein are not needed for attachment of control line 113
along the entire well interval. They are only required for the
interval where the control line 113 needs to be cut/split, released
and removed in conjunction with a plug and abandonment
operation.
[0097] FIG. 6 illustrates the scenario where the control line 113
has been removed from the relevant interval by means of the
techniques proposed herein. Do note that this normally takes place
at a time where the initial steps of a plug and abandonment
operation is finished, hence the holes 119 are punched in the
tubing 108 and the deep set mechanical barrier 118 is
installed.
[0098] FIG. 7 illustrates the scenario where the relevant interval
has been cemented; this is the new abandonment scenario further to
the philosophy and techniques proposed herein. One final step of
the abandonment process not illustrated herein is related to the
removal of the x-mas tree 111, the flow line 116 and the upper
sections of the casing 102.
[0099] As mentioned above, the exact design and number of the novel
clamps that are proposed herein may vary. In one embodiment of the
invention, the operation of relevant clamps such as the top clamp
501, intermediate clamp(s) 502, 502' and bottom clamp 503 to
perform the required plug and abandonment steps (such as splitting,
releasing and accessing the control line) is achieved by means of
wireline manipulation techniques. In another embodiment, the
operation is conducted by means of system manipulation via the
control line 113. In still another embodiment, the components are
operated by means of mechanical systems, such as mechanical
counters and activation mechanisms, operated by manipulating tubing
pressure, annulus pressure or both according to a pre-defined
interval of pressure impulses defined by amplitude, duration,
frequency and similar. In one embodiment, the operation is
conducted by means of a combination of the above techniques.
[0100] FIG. 8a and FIG. 8b illustrates one embodiment of a bottom
clamp 503 associated with one embodiment of the invention. Do note
that the figures serve the purpose as non-limiting examples and
illustrations only.
[0101] FIG. 8a illustrates a sectional view of the bottom clamp 503
seen from the side, whereas FIG. 8b illustrates the same section,
uncut and as seen from the front looking from right to left in FIG.
8a towards the side where the control line 113 is attached.
[0102] For this embodiment, the bottom clamp 503 replaces the
collar 402 of FIG. 4, meaning that the tubing joints 401 are
screwed directly into the bottom clamp 503. Variations may apply,
such as using crossovers to the tubing and similar. This will be
appreciated by a person skilled in the art and not further
described herein.
[0103] For this embodiment, the purpose of the bottom clamp 503 is
merely to provide for a controlled method of cutting the control
line 113. In order to do this, the control line is located in a
groove 801 in the bottom clamp 503, and fixed to the bottom clamp
503 using holding means in the form of a block element 802 secured
with bolts 803. Finally, the bottom clamp 503 includes allocation
means in the form of an allocation and orientation profile 804 for
a wireline tool to be used in the plug and abandonment operation.
The profile 804 may be of similar design and shape as
orientation/allocation wedges used in conjunction with installation
of gas lift valves in side pocket mandrels. This will be
appreciated by a person skilled in the art and is no further
referred to herein.
[0104] FIG. 9a and FIG. 9b illustrate the process of cutting the
line 113 for the given embodiment of the bottom clamp 503. Here, a
line manipulation apparatus in the form of a tailored wireline tool
901 is positioned correctly by means of an allocation bolt 902
orienting the tool 901 with respect to the allocation profile 804.
Note that the wireline tool 901 is shown in a side view in FIG. 9a
and not in a sectional view as the clamp 503 and tubing 108. Then,
a splitting means in the form of a transverse cutter element 903 is
used to create a transverse cut 904 of the line 113 just above the
block element 802. By means, the section of line 113 that is
located above the bottom clamp 503 has been split and released, and
can now be pulled upwards.
[0105] FIG. 10a and FIG. 10b illustrate one embodiment of an
intermediate clamp 502 associated with a similar embodiment of the
invention as FIGS. 8-9. The main difference from the bottom clamp
503 of FIGS. 8-9 is that in FIG. 10, the control line 113 is
attached to the clamp 502 by a holding means shown as a hinged
block element 1001.
[0106] FIG. 11a and FIG. 11b illustrate the process of releasing
the control line 113 from the intermediate clamp 502 for this given
embodiment of the invention. Similar to the process described in
FIGS. 8-9, a wireline 901 tool is applied for this purpose. The
wireline tool 901 may be the same as the one described in FIGS. 8-9
using different tool modules, or a different tool. However, in this
document, number references for similar wireline tool modules are
kept constant for simplicity purposes.
[0107] Again, the wireline tool 901 is positioned correctly by
means of an allocation bolt 902 orienting the tool with respect to
the allocation profile 804. Then, a longitudinal cutter element
1101 is applied in a pattern illustrated by arrow 1102 to create a
longitudinal cut 1103 of the hinged block element 1001 as
illustrated in FIG. 11b. Thus, when a section of the control line
113 has been split and released above the lower block element 802
as illustrated in FIGS. 9a and 9b, the section of control line 113
that is located above the bottom clamp 503 and the intermediate
clamp 502 can now be pulled upwards. By means, the hinge 1001 does
no longer impose any holding force on the control line 113. In one
embodiment, the hinge 1001 is designed to open somewhat when cut,
for example by pre-tensioning it against a shoulder when tightening
the bolts 803. The cutting element 1101 as well as other cutting
elements described herein may be selected from the group
comprising: mechanical means such as blade/saw/grinder type
cutters; plasma cutters; chemical cutters; explosive cutters or a
combination of one or more thereof. This will be appreciated by a
person skilled in the art and is no further referred to herein.
[0108] In an alternative embodiment (not shown), the block element
1001 of the intermediate clamp 502 has a saw-tooth surface on the
side that imposes force on the control line 113. By means, this
allows for one-way travel of the control line 113, and no cutting
exercise is required to operate this, simplifying the total
operation of releasing and removing the control line 113 from the
interval of interest. This saw-tooth surface allows displacement of
the control line 113 in one direction, but not in the opposite
direction. A similar saw-tooth surface can also be applied on the
part of the intermediate clamp 502 that the control line 113 rests
on, or on both the block element 1001 and the clamp 502.
[0109] The control line 113 associated with the top clamp 501
and/or bottom clamps 503 could also be designed having a
self-disconnect system to remove the need to cut or manipulate the
line 113 loose from the clamp being in the opposite end of where it
is intended to pull/push the control line 113 out of the annular
segment in question.
[0110] As would be appreciated by a person skilled in the art,
combinations of the above features could also be included in
relevant embodiments, such as the inclusion of a saw-tooth or
similar one-way feature of block elements 802 shown in FIGS. 8 and
9 associated with top- or bottom clamps 501, 503.
[0111] FIG. 12a and FIG. 12b illustrate one embodiment of a top
clamp 501 associated with a similar embodiment of the invention as
in FIGS. 8-11. As for the bottom clamp 503 of FIGS. 8-9, the
control line 113 is attached to the clamp 502 by means of a block
element 802.
[0112] The main difference is that the top clamp 501 is provided
with a pulling profile 1201 on its internal wall, adjacent to the
block element 802.
[0113] FIG. 13a and FIG. 13b illustrate the process of releasing
the control line 113 from the top clamp 501 for the given
embodiment of the invention as described in FIGS. 8-11, and
moreover the process of removing the control line 113 from the
relevant section of the well. Here, the wireline tool 901 is
positioned in a similar way to what was described for the previous
figures. A latching/gripping element 1301 of the wireline tool 901
is operated to engage with the pulling profile 1201. A multi
directional cutter 1302 is applied to make a rectangular shaped cut
1303, surrounding the entire block element 802. A groove 1304 is
included in the arrangement to provide for space between the
cutting element and the control line 113. The intention with the
space is to avoid accidentally cutting the control line 113 below
the block element 802. The reason for avoiding cutting the control
line below the block element 802 will be apparent by studying FIGS.
14a and 14b. Such protection against accidental cutting could be
sought in various ways. This would be appreciated by someone
skilled in the art and is no further referred to herein. The
rectangular cut 1303 may be difficult to make in one go, whilst the
latching element 1301 is engaged to the pulling profile 1201. In
one embodiment, one or more of the cutting operations required to
create the cut 1301 is/are performed prior to engaging the latching
element 1301 to the pulling profile 1201, whereas the remaining
cutting operations are performed after engagement.
[0114] FIG. 14a and FIG. 14b illustrate the process of removing the
control line from the relevant section in the well for this given
embodiment, following the operative steps described in FIGS. 8-13.
Here, the latching element 1301 is retracted into the body of the
wireline tool 901, bringing the pipe segment defined within the
rectangular shaped cut 1303 holding the block element 802 with it.
As the block element 802 still exerts a strong holding force on the
control line 113, this can now be pulled out by means of the
wireline tool 901. In one embodiment, the control line is pulled
all the way to the surface and displaced of. This embodiment may
entail a challenge with respect to wireline lubricator space
required to bring out a >50 meter long object. In another
embodiment, the wireline is used to lower the control line 113
segment to a location below the interval L to be cemented (see FIG.
7) and drop it, hence dispose of it in that section of the well.
Thus, in FIG. 14a the wireline tool 9001 is both a manipulation
apparatus and a retrieval apparatus arranged for bringing or
displacing the portion of the line 113 from the outside to the
inside of the tubing 108.
[0115] FIG. 15a and FIG. 15b illustrate a slightly different
arrangement and method to achieve the same result as described in
relation to FIGS. 12-14. Here, the top clamp 501 is provided with a
wedge ring 1501 which has a wedge protrusion 1502 as an integral
part of it. When installed, the wedge ring 1501 is compressing a
spring 1503, which again forces the wedge protrusion 1502 down
abutting the block element 802. By means, when making a similar
square cut 1303 as illustrated in FIG. 14b, the wedge protrusion
biased by the spring 1503 will urge the piece that is cut loose
inwards towards the center or bore of the tubing 108. This is
illustrated in FIGS. 16a and b. A potential benefit with this
embodiment is that the tubing piece that is cut loose now can be
collected by means of a collector module 1504 of the wireline tool.
Such a collector module 1504 may provide a more simple design and
hence more reliable than the latching element 1301 of the previous
embodiment. Moreover, the collector module 1504 may not cause the
same spatial conflicts with the cutter 1302 when creating the cut
1303 as could be the situation with the latching element 1301.
[0116] One main benefit with the embodiments described in FIGS.
8-16 is that the clamp modules do not introduce any new leakage
points to the completion than what already exist between tubing
joints and collars as per current practice. However, the
embodiments shown in FIGS. 8-16 requires relatively sophisticated
wireline tooling to operate. In the following section, alternative
embodiments, in particular embodiments that do not require pipe
cutting modules are illustrated.
[0117] FIG. 17a and FIG. 17b show an alternative embodiment of the
top clamp 501. A pulling profile 1201 is integrated in a modular
pipe wall segment 1701, which is initially integrated in the top
clamp 501. A seal 1702 provides for the barrier integrity between
the inside and outside of the tubing 108. The pipe wall segment
1701 is fixed to the top clamp 501 by a locking means, which in the
embodiment shown is a lock pin 1703 initially located in a locking
position inside a lock groove 1704. For the illustrated embodiment,
the lock pin 1703 forms an integral part of lock ring 1705, which
is initially held in a lower (locking) position by lock spring
1706. Finally, for this embodiment the top clamp 501 includes a
splitting means in the form of a cutting module 1707, such as a
cutting blade.
[0118] FIG. 18a and FIG. 18b illustrate the initial operating step
of the top clamp 501 embodiment from FIG. 17 at a stage where plug
and abandonment activities have been initiated. As described for
the embodiment above, a tailored wireline tool 901 is positioned
correctly by means of an allocation bolt 902 orienting the tool
with respect to the allocation profile 804. Then, a
latching/gripping element 1301 of the wireline tool 901 is operated
to engage with the pulling profile 1201. The next step is to unlock
or release the pipe wall segment 1701 from the top clamp 501. This
is done by operating a lock manipulation module 1801 of the
wireline tool 901. For this embodiment, the lock manipulation
module 1801 engages with the lock ring 1705 and pushes this
upwards, as indicated by arrow 1802. This causes the lock pin 1703
to disengage from the lock groove 1704. Upon removing the lock
function, the pipe wall segment 1701 can be disengaged from the top
clamp 501 by means of operating the latching/gripping element 1301
of the wireline tool 901. When pulling the wall segment 1701
inwards, the cutting module 1707 cuts the control line 113. This is
further illustrated in FIG. 19a and FIG. 19 b. Subsequently, the
control line 113 can be pulled out of the well, alternatively
removed from the well interval to be cemented and disposed of
elsewhere in the well.
[0119] Again, it is emphasized that details shown in this document
illustrate possible system functions only. For example, the number
and design of locks related to the embodiment shown in FIGS. 17-19
may vary, and may in alternative embodiments vary significantly
from what is illustrated herein, however the functionality remains
similar.
[0120] FIG. 20a and FIG. 20b show yet another embodiment of the top
clamp 501. A portion of the control line 113 runs through a sealed
cavity 2001 defined by an outer cover lid 2002, the body of the top
clamp 501, and an inner mandrel 2003. The inner mandrel 2003 seals
against the cavity 2001 by means of mandrel seals 2004, 2004'. The
cover lid 2002 seals against the cavity by means a cover seal 2005
and line seals 2006, 2006'. The line seals 2006, 2006' surround the
control line 113, to form a seal around this.
[0121] Experts in the art will appreciate that the task of
obtaining 100% tight seals may be challenging from design,
operational and material related perspectives. In one embodiment of
the invention, the seals 2006, 2006' (as well as the other seals
described herein) may therefore not be pressure proof seals, but
rather functioning as efficient flow restrictors, enabling the
operation of pumping the control line 113 out of the annulus
between the tubing 108 and casing 102 using techniques to create a
pressure differential across seals 2006, 2006'. This is explainer
further in the following paragraphs.
[0122] FIG. 20a discloses a mandrel 2003 provided with a wireline
engagement profile 2007. The top clamp 501 is provided with a
mandrel recess 2008 to allow for a defined longitudinal
displacement of the mandrel 2003.
[0123] Inside the cavity 2001, the control line 113 is attached to
the mandrel 2003 by means of an attachment clamp 2009. Also, inside
the cavity 2001, the control line 113 is thread through a cutting
module 2010 that forms an integral part of the cover lid 2002.
[0124] In a preferred embodiment, the segment of control line 113
inside the cavity 2001 has a stop system associated with it,
preventing it from being pumped into the annulus on the outside of
the tubing 108. Such a stop system could involve one-way, saw-tooth
profiled surfaces where the control line 113 is resting against the
lid 2002 or the solid body of the top clamp 501. Alternatively,
such a stop system be achieved by providing geometrical anomalies
on the control line 113, such as for example arranging stop rings
on the line, that have a size that does not allow for the control
line 113 to be pumped backwards through the line seals 2006, 2006'
and into the annulus.
[0125] FIG. 21a and FIG. 20b illustrate the engagement of a mandrel
manipulation wireline tool 2101 to the engagement profile 2007 of
the mandrel 2003. More specifically, engagement dogs 2102 of the
wireline tool 2101 are in engagement with the profile 2007.
[0126] FIG. 22a and FIG. 22b illustrate the wireline tool 2101
pulling the mandrel 2003 upwards. This results in the cavity 2001
being opened towards the bore of the tubing 108. In the same
process, the clamp 2009 with the control line 113 attached to it
moves upwards with respect to the cutting module 2010, resulting in
the control line 113 being cut by the cutting module 2010. For the
illustrated embodiment, this entails a loose end 2201 of the
control line 113 being positioned adjacent to an opening 2202
between the cavity 2001 and the bore of the tubing 108.
[0127] In one embodiment, similar features as those shown in FIGS.
20-22 are associated with the bottom clamp 503 rather than the top
clamp 501. In such embodiments, the top clamp 501 may only have
features related to splitting and releasing the control line 113
inside it, and no feature for creating the said opening 2202
between the cavity 2001 and the bore of the tubing 108. One reason
for swapping the said functionalities between the top clamp 501 and
the bottom clamp 503 is that it may be desired to pump the control
line 113 downwards into the well during the subsequent operational
step(s).
[0128] One such scenario is described in FIG. 23a and FIG. 23b
illustrating the resulting status of the well and control line
system after the operation of a bottom clamp 503 according to a
method as illustrated in FIG. 20-22. The control line system is
defined by the control line 113 having one loose end 2201 exposed
to the bore of the tubing 108, the seal 2006 forming a seal between
the bore of the tubing 108 and the annulus between the tubing 108
and the casing 102. For this embodiment and given status of the
well operation, the control line 113 has been split and released in
the top clamp 501, and also released from the intermediate clamps
502, 502'. An "x" is used to illustrate the fact that these modules
have been operated according to said functions, despite the control
line 113 still being illustrated to run through them.
[0129] FIG. 24a and FIG. 24b illustrate one technique for
retrieving the control line 113 further to a scenario defined in
FIG. 23. In FIG. 24a and FIG. 24b a control line collecting
wireline tool 2401 is intervened into the well. The tool 2401
comprises a lower collector chamber 2402, with at least one
collector port 2403 being positioned adjacent to the loose end 2201
of the control line 113. The lower collector chamber 2402 module
also includes a lower packer element 2404 and an upper packer
element 2405 that, when in a "control line 113 retrieval position",
straddles the opening 2202 of the bottom clamp 503 illustrated in
FIG. 22a, including the seal 2006. The wireline tool 2401 also
includes a suction chamber 2406 containing a gas, typically air, at
a low pressure, equal or close to atmospheric pressure. The
collector chamber 2402 and the suction chamber 2406 are initially
separated by a piston 2407.
[0130] When the wireline tool 2401 is correctly positioned, as
illustrated in FIG. 25a and FIG. 25b, and the packer elements 2404,
2405 are engaged to the tubing 108, the piston 2407 is released.
Methods for releasing such pistons will be appreciated by a person
skilled in the art and is therefore not described in any further
details herein. Now, the piston 2407 travels up into the suction
chamber 2406, due to the pressure difference between the suction
chamber 2406 and the surroundings. As the packer elements 2404,
2405 forms an enclosure as illustrated in the figure, the control
line 113 is forced towards the inside of the tubing 108 and the
collector chamber 2402, driven by the high pressure being present
in the annulus between the tubing 108 and the casing 102. The
result is a separated control line segment 2501 being collected
into a collector chamber 2406 in a controlled fashion.
[0131] This embodiment and method may have a challenge in relation
to detecting whether or not all of the control line 113 has been
removed from the interval L (se FIG. 3). In one embodiment,
monitoring of pressure in the annulus between the tubing 108 and
the casing 102 is used to detect pressure change indications
verifying that all the control line 113 has been removed from the
relevant interval.
[0132] FIG. 26a and FIG. 26b illustrate a slightly different
embodiment of the wireline collector tool 2401. Here, the piston
2407 has been replaced by a channel 2601, located above the upper
packer element 2405. Instead of using an atmospheric suction
chamber 2406 as illustrated in FIG. 24a and FIG. 24b, the control
line is removed from the interval L (see FIG. 3) by pumping fluids
down the annulus between the tubing 108 and the casing 102 using a
surface pump (not shown), whilst opening valves on the top of the
well, allowing for a return of the same fluid via the bore of the
tubing 108. By means, the control line 113 will be pumped out of
the interval L and into the collector chamber 2402 of the wireline
tool 2401. In one embodiment of the invention, the channel 2601
includes a filter (not shown) to prevent the control line 113 being
pumped out of the wireline tool 2401.
[0133] For the method of pumping out the control line 113 by
pumping down the annulus; in one embodiment of the invention, the
pressure patterns on the surface is monitored, on the pump side or
on the return side or both, to observe for a pressure change
associated with the control line 113 no longer plugging the center
channel of the seal 2006. For scenarios where the well is completed
with multiple control lines 113 the entry to the channel of the
seal 2006 may be provided with a ball or similar that is adapted to
drop into and plug the channel when the line 113 is pumped out of
it. This would entail a pressure change when all the lines are
pumped out of the interval, and the system channels is plugged by
components that are prevented from moving. Alternative so called
tell-tale systems indicating when the control line has been fully
removed from the interval could be envisaged. Such tell-tale
systems would be appreciated by a person skilled in the art.
[0134] Do note that the deep set barrier 118 forms a sealed
enclosure towards the bottom section of the well, providing for a
pumping/circulation pattern as described above, and preventing
unwanted so called bullheading of fluids into the reservoir.
[0135] FIG. 27 illustrates an embodiment where no wireline tool is
used to collect the control line 113 that has been pumped out.
Instead, for this embodiment, the control line 113 is allowed to
free-fall to a section of the well where it is left permanently. In
one embodiment of the invention, the control line 113 falls to a
section of the well that does not overlap with the interval L to be
cemented. In one embodiment of the invention, a wireline tool 901
is used to force the control line 113 down and bundle it to a more
compact form, ensuring that it does not overlap with the interval L
to be cemented.
[0136] In another embodiment of the invention, similar techniques
are used to displace the control line 113 to other locations inside
the tubing 108, as well as to other locations inside the annulus
between the tubing 113 and the casing 102. The important aspect is
that the control line 113 originally located across the interval
"L" of FIG. 3 has been removed from the interval, and to a location
where it does not conflict with the subsequent cementing operations
as well as other subsequent operations of the well abandonment
operation.
[0137] In some scenarios, a well may be completed with multiple
control lines 113. Control lines 113 may also be one or a
combination of electric and hydraulic control lines 113. For the
removal of hydraulic control lines 113, pumping and/or suction
techniques described herein, such as the techniques described in
FIGS. 22-26, may not be directly applicable, as a hydraulic control
line 113 is hollow, and will allow flow through the bore therein.
For such cases, it may be required to provide for a method of
sealing the bore of the line 113 prior to utilizing pumping or
suction methods to remove it from the interval L. In one
embodiment, the arrangement and method for cutting the control line
113 segment to be removed in the opposite end of the loose end 2201
adjacent to the opening 2202 as illustrated in FIG. 22, would
include a method for sealing off the control line 113 in such an
opposite end. In one embodiment, such method for sealing would
entail mechanical deformation of the control line 113. In another
embodiment, check valve functionality is activated at this
instance. For the latter case, the method for splitting"cutting"
the control line 113 may not be mechanical cutting, but rather a
controlled disconnection of the control line 113 at a point
designed in order to facilitate for this (i.e. a line coupling
designed for such purposes), meaning that the control line 113 as
well as the surrounding well mechanics and manipulation devices
have been designed for performing a controlled disconnection and
sealing of the control line 113 at such point. Techniques for this
would be appreciated by a person skilled in the art.
[0138] As a final remark, it should be emphasized that the method
according to the invention provides for retrieving or producing out
the control line 113 in both the top as well as the bottom end of
the indicated top/intermediate/bottom clamp 501,502,503 assembly,
and that the functionality of the clamp systems 501, 502, 503 as
described in the examples provided herein could be interchanged, so
that for alternative embodiments the functionality shown for the
top clamp 501 herein would apply for a bottom clamp 502 and vice
versa. Moreover, the invention provides for sequential removal of
the relevant length of control line, such as sectional movement of
control line 113 between two and two clamps 501, 502, 503,
respectively--potentially removing the need for intermediate clamps
502, 502'. In the latter case, the term "release of control line
113" referred to herein would not be associated with the release of
control line 113 from an intermediate clamp 502, but the release
from a top clamp 501 or bottom clamp 503. In one embodiment the
release activity takes place simultaneously to the
cutting/splitting activity. To achieve splitting, release and
removal of control line(s) 113 from the annulus between the tubing
108 and the casing 102, features as described or illustrated
herein, as well as any combination of described features could form
part of relevant embodiments.
[0139] In one embodiment of the invention, the operation of
relevant clamps such as the top clamp 501, intermediate clamp(s)
502/502' and bottom clamp 503 to perform the required plug and
abandonment steps, such as cutting/splitting, releasing and
removing the control line 113, is achieved by means of wireline
manipulation techniques. In another embodiment, the operation is
conducted by means of system manipulation via one or multiple
control line(s) 113 in a similar way to how so-called smart well
components of wells are manipulated. As an example, the mandrel
2003 of FIG. 20 could be manipulated to provide for the
cutting/splitting, release and removal of control line 113 by
operations controlled via the control line 113 using known
actuating techniques such as hydraulic, electro hydraulic or
electric actuation, or other techniques appreciated by a person
skilled in the art. In still another embodiment, relevant
components are operated by means of mechanical systems, such as
mechanical counters and activation mechanisms, operated by
manipulating tubing pressure, annulus pressure or both according to
a pre-defined interval of pressure impulses defined by amplitude,
duration and similar. Norwegian patent application NO 20110246
filed by the present applicant describes one such arrangement and
technique. In one embodiment the above operations are conducted
using wireless techniques, and that autonomous, remotely operated
downhole arrangements perform one or more of the required
cut/split, release and remove operations. In one embodiment, the
operation is conducted by means of a combination of the above
techniques. Provided an otherwise equal parameter comparison; the
latter described methods (the methods not requiring wireline
manipulation) would be preferred over methods that require wireline
manipulation, as the cost of conducting a wireline operation can
become somewhat high in comparison.
[0140] In one embodiment, the clamping means 501, 502, 503 are not
in the form of collars that replaces the collar 402 of FIG. 4. In
some embodiments they may be designed in a similar fashion as prior
art cable clamps 403 illustrated in FIG. 4. For such embodiments,
the clamping means 501, 502, 503 and holding means 802, 1001, 2009
may be merged into one common functionality. Moreover, for such
cases, the collars 402 may be provided with external orientation
profiles to enable the mounting of the clamping means 501, 502, 503
with an orientation that provides for the use of techniques
described herein, and internal orientation profiles 804, 2007; 902,
2102 for the orientation of manipulation devices as described
herein.
* * * * *