Field of the invention
[0001] The present invention relates to an annular barrier for being expanded in an annulus
between a well tubular structure and a wall of a borehole or another well tubular
structure downhole for providing zone isolation between a first zone having a first
pressure and a second zone. Furthermore, the present invention relates to a downhole
system.
Background art
[0002] In recent years, the number of tool intervention operations in wells has increased,
and hydrocarbon wells are therefore made without electrical lines running inside the
casing which may conflict with intervention tools.
[0003] However, electricity is still needed for powering electrical devices arranged inside
or outside the casing several kilometres down, as the completions become more and
more developed, and this conflicts with the importance of keeping the casing free
of electrical lines without breaking the main barriers of the well.
Summary of the invention
[0004] It is an object of the present invention to wholly or partly overcome the above disadvantages
and drawbacks of the prior art. More specifically, it is an object to provide an improved
annular barrier and downhole system in which powering of electrical devices arranged
inside or outside a well tubular structure several kilometres down is possible while
still being able to perform tool intervention.
[0005] The above objects, together with numerous other objects, advantages and features,
which will become evident from the below description, are accomplished by a solution
in accordance with the present invention by an annular barrier for being expanded
in an annulus between a well tubular structure and a wall of a borehole or another
well tubular structure downhole for providing zone isolation between a first zone
having a first pressure and a second zone, the annular barrier comprising:
- a tubular metal part for mounting as part of the well tubular structure, the tubular
metal part having a first expansion opening, an axial extension and an outer face,
- an expandable sleeve surrounding the tubular metal part and having an inner face facing
the tubular metal part and an outer face facing the wall of the borehole,
- a first connection part and a second connection part configured to connect a first
end and a second end, respectively, of the expandable sleeve with the tubular metal
part, and
- an annular space between the inner face of the expandable sleeve and the tubular metal
part,
wherein the annular barrier further comprises an electrical conductor extending from
the first connection part to the second connection part.
[0006] By having the electrical conductor extending from the first connection part to the
second connection part, electricity can be supplied to an electric device further
down the well without breaking the barrier between the first and the second zone.
The connection parts do not move, and it is thus simple to provide a sufficient seal
between the connection parts and the electrical conductor.
[0007] Thus, the connection parts may be non-slidable in relation to the tubular metal part.
[0008] In an embodiment, the annular barrier described above may further comprise a tunnel
arranged in the space between the first connection part and the second connection
part, in which tunnel the electrical conductor extends.
[0009] Furthermore, the first and the second connection part may each have an electrical
connection configured to connect with the electrical conductor.
[0010] The annular barrier described above may further comprise a sealing means for sealing
around the electrical conductor.
[0011] In addition, the electrical conductor may be soldered to the connection parts.
[0012] Also, the sealing means may seal around the electrical conductor between the electrical
conductor and one of the connection parts or the tunnel.
[0013] In addition, the annular barrier described above may further comprise a sensor electrically
connected with the electrical conductor.
[0014] The expandable sleeve may be made of metal so that the annular barrier is a metal
annular barrier.
[0015] Furthermore, at least one sealing means may be provided on the outer face of the
expandable sleeve of the metal annular barrier.
[0016] Also, the annular barrier may comprise an expansion unit so that fluid passing the
expansion opening is led past the expansion unit before entering the annular space.
[0017] In addition, the expansion unit may comprise a permanent closing mechanism for preventing
fluid communication between the well tubular structure and the annular space in a
first position.
[0018] Furthermore, the permanent closing mechanism is a two-way valve comprising a second
position in which fluid communication between the annular space and the annulus or
the second zone is provided.
[0019] The present invention furthermore relates to a downhole system comprising:
- a well tubular structure, and
- a first annular barrier being an annular barrier described above, wherein the tubular
metal part is mounted as part of the well tubular structure.
[0020] The downhole system may further comprise a first electrical unit arranged on an outer
face of the well tubular structure and electrically connected with the electrical
conductor.
[0021] In an embodiment, the electrical unit may be an inductive coupler part.
[0022] Furthermore, the downhole system may further comprise a second electrical unit arranged
inside the well tubular structure and configured to abut an inner face of the well
tubular structure.
[0023] In an embodiment, the second electrical unit may be an inductive coupler part.
[0024] The downhole system may further comprise a second well tubular structure arranged
at least partly within a first well tubular structure, the second electrical unit
being arranged outside the second well tubular structure.
[0025] Moreover, the second electrical unit may be electrically connected to a third electrical
unit via a second electrical conductor.
[0026] In addition, downhole system may further comprise a second annular barrier through
which the second electrical conductor extends.
[0027] Also, the downhole system may further comprise a lateral tubular structure connected
with one of the well tubular structures, and wherein a third electrical unit may be
arranged outside the lateral tubular structure.
[0028] Additionally, the downhole system may further comprise a tool arranged in the well
tubular structure, the tool comprising an inductive tool coupler part configured to
be electrically connected with the inductive coupler part.
[0029] Finally, the downhole system may further comprise a sensor arranged outside one of
the well tubular structures.
Brief description of the drawings
[0030] The invention and its many advantages will be described in more detail below with
reference to the accompanying schematic drawings, which for the purpose of illustration
show some non-limiting embodiments and in which
Fig. 1 shows a cross-sectional view of an annular barrier having an electrical conductor,
Fig. 2 shows a cross-sectional view of an annular barrier having an electrical conductor
connected to connection parts via electrical connections,
Fig. 3 shows a cross-sectional view of another annular barrier having a tunnel in
which the electrical conductor runs,
Fig. 4 shows a cross-sectional view of a downhole system,
Fig. 5 shows a cross-sectional view of another downhole system having several electrical
units,
Fig. 6 shows a cross-sectional view of yet another downhole system having a lateral
tubular structure with a further electrical unit,
Fig. 7 shows a cross-sectional view of another downhole system having several electrical
units arranged down the well, and
Fig. 8 shows a cross-sectional view of yet another downhole system having several
electrical units arranged down the well and in a lateral tubular structure.
[0031] All the figures are highly schematic and not necessarily to scale, and they show
only those parts which are necessary in order to elucidate the invention, other parts
being omitted or merely suggested.
Detailed description of the invention
[0032] Fig. 1 shows an annular barrier 10 in a well, expanded in an annulus 2 between a
well tubular structure 1 and a wall 5 of another well tubular structure downhole for
providing zone isolation between a first zone 101 and a second zone 102. The annular
barrier 10 comprises a tubular metal part 7 for mounting as part of the well tubular
structure 1, the tubular metal part having an axial extension L along the longitudinal
extension of the well tubular structure. The tubular metal part 7 has a first expansion
opening 3 through which pressurised fluid enters for expanding the annular barrier
10. The annular barrier 10 further comprises an expandable sleeve 8 surrounding the
tubular metal part 7 and having an inner face 9 facing an outer face 4 of the tubular
metal part, and an outer face 16 of the expandable sleeve 8 faces the wall of the
well tubular structure 1. A first end 13 of the expandable sleeve 8 is connected to
the tubular metal part 7 by a first connection part 11, and a second end 14 of the
expandable sleeve is connected to the tubular metal part by a second connection part
12. Thus, an annular space 15 is enclosed between the inner face 9 of the expandable
sleeve 8 and the tubular metal part 7, which space expands as the expandable sleeve
expands due to the pressurised fluid let into the annular space. The annular barrier
10 further comprises an electrical conductor 17 extending from the first connection
part 11 to the second connection part 12 and through the annular space 15 so that
electricity can be conducted past the annular barrier to an electrically demanding
unit further down the well without breaking the seal between the first and the second
zone provided by the annular barrier.
[0033] In Figs. 2 and 3, the annular barrier 10 is expanded between the well tubular structure
1 and the wall 5 of a borehole 6. In Fig. 2, the first and the second connection part
11, 12 each have an electrical connection 24 connected to the electrical conductor
17, so that the electrical conductor is formed of a first part 35 extending in a first
zone 101, a second part 36 extending inside the annular barrier 10, and a third part
37 extending in a second zone 102. The electrical conductor 17 can thus be formed
of several parts forming one electrical conductor.
[0034] In Fig. 3, the annular barrier 10 further comprises a tunnel 18 in the form of a
tube arranged in the annular space 15 and extending between the first connection part
11 and the second connection part 12. The electrical conductor 17 runs in the tunnel
18, and a sealing means 19 is provided around the tunnel and around the electrical
conductor 17 so that fluid from the first zone 101 is hindered in flowing into the
second zone 102, and vice versa. Instead of having a sealing means 19 around the electrical
conductor 17 in the tunnel 18, the tunnel may be designed to collapse at a certain
pressure when the annular barrier 10 expands, as the pressure inside the annular space
15 forces the tunnel to collapse and shrink around the electrical conductor.
[0035] As shown in Fig. 2, the sealing means 19 may also be arranged in such a way that
it seals directly around the electrical conductor 17 and is arranged in the connection
parts 11, 12 and/or as part of the electrical connections 24. The annular barrier
10 further comprises a sensor 23 electrically connected with the electrical conductor
17 for taking measurements of e.g. pressure and temperature or the expansion ratio
of the expandable sleeve 8 during expansion of the annular barrier. As can be seen,
the electrical conductor 17 extends further past the sensor 23 to be electrically
connected with other electrical devices further down the well.
[0036] In Fig. 3, the annular barrier 10 comprises an expansion unit 41 arranged at the
first expansion opening 3 so that the pressurised fluid enters the first expansion
opening 3 and flows into the expansion unit 41 before being led into the annular space
15. The expansion unit 41 comprises a permanent closing mechanism which closes the
fluid communication between the inside of the well tubular structure 1 and the annular
space 15 in a first position after expansion of the expandable sleeve 8 and thus the
annular barrier 10, and in a second position allows for fluid communication between
the first zone 101 and the annular space 15 so that the pressure can be equalised
therebetween, should the pressure in the second zone 102 increase during e.g. fracturing.
Thus, the permanent closing mechanism is a two-way valve and may even function as
a three-way valve where fluid may also be led from the well tubular structure to the
annulus.
[0037] Fig. 4 shows a downhole system 100 comprising the well tubular structure 1 and a
first annular barrier 10 being the annular barrier described above, where the tubular
part is mounted as part of the well tubular structure. The electrical conductor 17
is led past the annular barrier 10, as described above, without breaking the barrier
between the first zone 101 and the second zone 102 provided by the annular barrier
10. Furthermore, the electrical conductor 17 is electrically connected to a first
electrical unit 20 arranged on an outer face 21 of the well tubular structure 1. The
electrical unit 20 is an inductive coupler part 20A, meaning that a tool inside the
well tubular structure 1 can be recharged by abutting the inner face of the well tubular
structure opposite the inductive coupler part, and the tool can thus be charged without
having to emerge all the way to surface or the well head, since power is conducted
in the electrical conductor past one or more annular barrier(s) and further down the
well. Furthermore, the well tubular structure 1 is intact, as the inductive coupler
part 20A is arranged on the outside of the well tubular structure.
[0038] The downhole system 100 of Fig. 5 further comprises a second electrical unit 20B
arranged inside the first well tubular structure 1, 1A configured to abut an inner
face 22 of the first well tubular structure and a second well tubular structure 1B
arranged partly within the first well tubular structure 1A. The second electrical
unit 20B is an inductive coupler part 20C, and electricity is thus conducted through
the first well tubular structure 1A and further conducted in the electrical conductor
17 outside of the second well tubular structure 1B. The downhole system 100 further
comprises a second annular barrier 10B having a tubular metal part 7 mounted as part
of the second well tubular structure 1B and expanded between the first well tubular
structure 1, 1A and the second well tubular structure 1, 1B. The electrical conductor
17 extends through the first annular barrier to the first electrical unit, and a second
electrical conductor 17B extends from the second electrical unit 20B through a third
annular barrier 10C to a third electrical unit 20D which can then be arranged several
kilometres further down the well. The second electrical unit 20B is electrically connected
to the third electrical unit 20D via the second electrical conductor 17B, and a tool
inside the second well tubular structure 1B can thus be electrically powered several
kilometres down the well by abutting the inner face of the second well tubular structure
opposite the inductive coupler part of the second electrical unit 20B
[0039] The downhole system 100 shown in Fig. 6 comprises a lateral tubular structure 31
extending from a window opening in the second well tubular structure 1B. The downhole
system 100 further comprises a tool 50 arranged in the lateral tubular structure 31
of the well tubular structure 1, and the tool comprises an inductive tool coupler
part 51 configured to be electrically connected with the inductive coupler part when
the tool abuts the inner face of the lateral tubular structure 31, as shown. The downhole
system 100 further comprises a sensor 23 arranged outside one of the second well tubular
structures for measuring e.g. temperature and/or pressure.
[0040] In Fig. 7, the downhole system 100 has a sleeve 55 movable by the sleeve control
57 for uncovering an aperture 54 or aligning a sleeve opening 58 with the aperture
54 allowing fluid to flow therethrough. The sleeve control 57 further comprises an
inductive tool coupler part 51 for receiving control signals from surface to open,
choke or close fluid communication through the aperture. The sleeve control 57 is
thus permanently installed in the production casing 1B, ready to move the sleeve from
one position to another in order to choke, open or close fluid communication from
the reservoir. The sleeve control 57 has its own power supply and can operate on its
own when receiving a control signal during production of fluid from the reservoir,
without the well being intervened by commonly used intervention tools. The inductive
tool coupler part 51 of the sleeve control 57 of the tool 50 is arranged in the fixation
unit 61 abutting the restriction 39 and the inner face of the casing 1B. The first
electrical unit 20a arranged on an outer face of the first well tubular structure
1A and a second electrical unit 20b arranged on an inner face of the first well tubular
structure 1A communicate via the casing/well tubular structure 1A. The second electrical
unit 20b and a third electrical unit 20C arranged further down the well communicate
via the electrical conductor 17 running through an annular barrier 10. The inductive
tool coupler part 51 and the third electrical unit 20C are electrically connected
via electromagnetic induction and transfer signals and electrical power between them
through the well tubular structure 1B. The sleeve control 57 comprises a first part
68 having members 69 engaging the profile 56, and a second part 70 having the fixation
unit 61 fixating the sleeve control 57 in the casing. The sleeve control 57 comprises
an actuator 72 for moving the first part 68 in relation to the second part 60, and
a power supply 64, such as a battery, supplying power to the actuator. The battery
may be charged through the well tubular structure 1B by the third electrical unit
20C.
[0041] The power supply may also be recharged by the inductive tool coupler part 51 converting
mud pulses, an electrical field or acoustic waves into electrical energy. The inductive
tool coupler part 51 may also comprise a propeller 21A in connection with a generator
22A for recharging the power supply by converting rotational energy generated by fluid
in the production casing 2 into electrical energy, as shown in Fig. 7.
[0042] In Fig. 8, the downhole system 100 comprises completion components 55 where a first
part 5a of the completion component is a member 69 engaging the profile 56 of a second
part 5b of the completion component. Thus, the first part 5a of the completion component
is arranged at the component control 57. The inductive tool coupler part 51 of the
component control 57 is arranged in the fixation unit 61 abutting the restriction
39 and the inner face of the casing 2. The first electrical unit 20a arranged on an
outer face of the intermediate casing and a second electrical unit 20b arranged on
an inner face of the intermediate casing communicate via the well tubular structure
1A. The first electrical unit 20a is electrically connected to surface via wiring
17 extending through the main barrier 65. The first electrical unit 20a and the second
electrical unit 20b are electrically connected via electromagnetic induction and transfer
signals and electrical power between them through the intermediate casing 1A. The
third electrical unit 20c is connected with the second electrical unit 20b by means
of wiring or an electrical conductor, such as a cable, a cord or a wire running through
an annular barrier 10. The third electrical unit 20c is arranged on the outer face
of the production casing 1B further down the well but above the lateral tubular structure
81. A fourth communication unit 20d is arranged opposite the inductive tool coupler
part 51 of the component control 57. The third and fourth communication units are
electrically connected via wiring 17. The fourth communication unit 20d and the inductive
tool coupler part 51 transfer signals and electrical power between them via electromagnetic
induction through the production casing 1B. The third electrical unit 20c is furthermore
electrically connected with a fifth electrical unit 20e arranged outside the main
casing which is the production casing 1B. The fifth electrical unit 20e is arranged
opposite an inductive tool coupler part 51 of another component control 57 in the
main casing and transfers signals and power by means of electromagnetic induction
through the production casing 1B. Both the wiring 17 between the second electrical
unit 20b and the third electrical unit 20c and between the third electrical unit 20c
and the fourth electrical unit 20d runs past an annular barrier 10. The wiring 17
extends in through one of the connection parts 11, 12 connecting the expandable sleeve
8 with the tubular part 7, and past the space 15 and through the other connection
part further down the well. The wiring 17 of Fig. 8 between the third electrical unit
20c and the fifth electrical unit 20e extends past the lateral tubular structure 81
on the outside of the main casing 1B and through the annular barrier 10 arranged further
down the main casing.
[0043] All the communication units each comprises an inductive coupler for transferring
power from one communication unit to another through the casing by means of electromagnetic
induction. The casing may have non-magnetic sections opposite the communication units
to optimise the transfer by electromagnetic induction.
[0044] The tool may be a stroking tool which is a tool providing an axial force, e.g. for
opening or closing a sliding sleeve. The stroking tool comprises an electrical motor
for driving a pump. The pump pumps fluid into a piston housing to move a piston acting
therein. The piston is arranged on the stroker shaft. The pump may pump fluid into
the piston housing on one side and simultaneously suck fluid out on the other side
of the piston.
[0045] By fluid or well fluid is meant any kind of fluid that may be present in oil or gas
wells downhole, such as natural gas, oil, oil mud, crude oil, water, etc. By gas is
meant any kind of gas composition present in a well, completion, or open hole, and
by oil is meant any kind of oil composition, such as crude oil, an oil-containing
fluid, etc. Gas, oil, and water fluids may thus all comprise other elements or substances
than gas, oil, and/or water, respectively.
[0046] By a well tubular structure is meant any kind of pipe, tubing, tubular, liner, string
etc. used downhole in relation to oil or natural gas production.
[0047] In the event that the tool is not submergible all the way into the well tubular structure,
a downhole tractor can be used to push the tool all the way into position in the well.
The downhole tractor may have projectable arms having wheels, wherein the wheels contact
the inner surface of the well tubular structure for propelling the tractor and the
tool forward in thewell tubular structure. A downhole tractor is any kind of driving
tool capable of pushing or pulling tools in a well downhole, such as a Well Tractor®.
[0048] Although the invention has been described in the above in connection with preferred
embodiments of the invention, it will be evident for a person skilled in the art that
several modifications are conceivable without departing from the invention as defined
by the following claims.
1. An annular barrier (10) for being expanded in an annulus (2) between a well tubular
structure (1) and a wall (5) of a borehole (6) or another well tubular structure downhole
for providing zone isolation between a first zone (101) having a first pressure (P
1) and a second zone (102), the annular barrier comprising:
- a tubular metal part (7) for mounting as part of the well tubular structure, the
tubular metal part having a first expansion opening (3), an axial extension (L) and
an outer face (4),
- an expandable sleeve (8) surrounding the tubular metal part and having an inner
face (9) facing the tubular metal part and an outer face (16) facing the wall of the
borehole,
- a first connection part (11) and a second connection part (12) configured to connect
a first end (13) and a second end (14), respectively, of the expandable sleeve with
the tubular metal part, and
- an annular space (15) between the inner face of the expandable sleeve and the tubular
metal part,
wherein the annular barrier further comprises an electrical conductor (17) extending
from the first connection part to the second connection part.
2. An annular barrier according to claim 1, further comprising a tunnel (18) arranged
in the space between the first connection part and the second connection part, in
which tunnel the electrical conductor extends.
3. An annular barrier according to claim 1 or 2, wherein the first and the second connection
part each have an electrical connection (24) configured to connect with the electrical
conductor.
4. An annular barrier according to any of the preceding claims, further comprising a
sealing means (19) for sealing around the electrical conductor.
5. An annular barrier according to any of the preceding claims, further comprising a
sensor (23) electrically connected with the electrical conductor.
6. A downhole system (100) comprising:
- a well tubular structure (1), and
- a first annular barrier (10) being an annular barrier according to any of claims
1-4, wherein the tubular metal part is mounted as part of the well tubular structure.
7. A downhole system according to claim 6, further comprising a first electrical unit
(20) arranged on an outer face (21) of the well tubular structure and electrically
connected with the electrical conductor.
8. A downhole system according to claim 7, wherein the electrical unit is an inductive
coupler part (20A).
9. A downhole system according to any of claims 6-8, further comprising a second electrical
unit (20B) arranged inside the well tubular structure and configured to abut an inner
face (22) of the well tubular structure.
10. A downhole system according to claim 9, further comprising a second well tubular structure
(1B) arranged at least partly within a first well tubular structure (1A), the second
electrical unit being arranged outside the second well tubular structure.
11. A downhole system according to claim 9 or 10, wherein the second electrical unit is
electrically connected to a third electrical unit (20D) via a second electrical conductor
(17B).
12. A downhole system according to claim 11, further comprising a second annular barrier
(10B) through which the second electrical conductor extends.
13. A downhole system according to any of claims 6-12, further comprising a lateral tubular
structure (31) connected with one of the well tubular structures, and wherein a third
electrical unit is arranged outside the lateral tubular structure.
14. A downhole system according to any of claims 6-13, further comprising a tool (50)
arranged in the well tubular structure, the tool comprising an inductive tool coupler
part (51) configured to be electrically connected with the inductive coupler part.
15. A downhole system according to any of claims 6-14, further comprising a sensor (23)
arranged outside one of the well tubular structures.