U.S. patent application number 13/102891 was filed with the patent office on 2012-11-08 for expandable downhole casing coupling locator tool.
This patent application is currently assigned to SMITH INTERNATIONAL, INC.. Invention is credited to James Bain, Brian Cruickshank, Charles Dewey, Murray Fearn, Mahavir Nagaraj.
Application Number | 20120279709 13/102891 |
Document ID | / |
Family ID | 47089461 |
Filed Date | 2012-11-08 |
United States Patent
Application |
20120279709 |
Kind Code |
A1 |
Bain; James ; et
al. |
November 8, 2012 |
EXPANDABLE DOWNHOLE CASING COUPLING LOCATOR TOOL
Abstract
A downhole locator apparatus, including a tool body having a
central axis defined therethrough, and at least one locator lug
radially expandable from the tool body, in which the at least one
locator lug is configured to be received in an annular groove
formed in an inner surface of a casing string, in which the at
least one locator lug is configured to move radially between a
retracted position and an expanded position.
Inventors: |
Bain; James; (Montrose,
GB) ; Fearn; Murray; (Aberdeen Grampian, GB) ;
Cruickshank; Brian; (The Woodlands, TX) ; Dewey;
Charles; (Houston, TX) ; Nagaraj; Mahavir;
(Spring, TX) |
Assignee: |
SMITH INTERNATIONAL, INC.
Houston
TX
|
Family ID: |
47089461 |
Appl. No.: |
13/102891 |
Filed: |
May 6, 2011 |
Current U.S.
Class: |
166/298 ;
166/206; 166/382 |
Current CPC
Class: |
E21B 29/06 20130101;
E21B 47/09 20130101 |
Class at
Publication: |
166/298 ;
166/206; 166/382 |
International
Class: |
E21B 29/06 20060101
E21B029/06; E21B 43/11 20060101 E21B043/11; E21B 23/01 20060101
E21B023/01; E21B 29/00 20060101 E21B029/00 |
Claims
1. A downhole locator apparatus, comprising: a tool body having a
central axis defined therethrough; and at least one locator lug
radially expandable from the tool body, wherein the at least one
locator lug is configured to be received in an annular groove
formed in an inner surface of a casing string, wherein the at least
one locator lug is configured to move radially between a retracted
position and an expanded position.
2. The apparatus of claim 1, further comprising an actuation
mechanism configured to move the at least one locator lug between
the retracted position and the expanded position.
3. The apparatus of claim 1, wherein the expanded position
comprises a first expanded position and a second expanded
position.
4. The apparatus of claim 3, wherein, in the first expanded
position, the at least one locator lug is engaged with the inner
surface of the casing string.
5. The apparatus of claim 3, wherein, in the second expanded
position, the at least one locator lug is engaged with the annular
groove formed between a first length of casing and a second length
of casing along the inner surface of the casing string.
6. The apparatus of claim 1, wherein the at least one locator lug
is coupled to at least one movable arm.
7. The apparatus of claim 6, wherein the at least one movable arm
is coupled to the tool body and is radially expandable from the
tool body.
8. The apparatus of claim 2, wherein the actuation mechanism is one
of a hydraulic actuation mechanism, a mechanical actuation
mechanism, an electro-hydraulic actuation mechanism, and an
electro-mechanical actuation mechanism.
9. A method of locating a casing coupling in a borehole, the method
comprising: disposing a locator apparatus into a borehole, the
locator apparatus comprising: a tool body having a central axis
defined therethrough; and at least one locator lug radially
expandable from the tool body, wherein the at least one locator lug
is configured to be received in an annular groove formed in an
inner surface of a casing string, wherein the at least one locator
lug is configured to move radially between a retracted position and
an expanded position; and moving the at least one locator lug
between the retracted position and the expanded position to
indicate a casing coupling location.
10. The method of claim 9, further comprising actuating the locator
apparatus at a predetermined location within the borehole.
11. The method of claim 10, wherein actuating the locator apparatus
comprises moving the at least one locator lug from the retracted
position to the expanded position.
12. The method of claim 9, wherein the expanded position comprises
a first expanded position and a second expanded position.
13. The method of claim 12, wherein, in the first expanded
position, the at least one locator lug is engaged with the inner
surface of the casing.
14. The method of claim 12, wherein, in the second expanded
position, the at least one locator lug is engaged with the annular
groove formed in the inner surface of the casing string.
15. The method of claim 9, further comprising determining a length
of the casing string within the borehole.
16. The method of claim 15, further comprising positioning the
locator apparatus at a predetermined distance from a drill bit
based on the determined length of the casing string within the
borehole.
17. The method of claim 9, further comprising deactuating the
locator apparatus at a predetermined location within the
borehole.
18. The method of claim 17, wherein deactuating the locator
apparatus comprises moving the at least one locator lug from the
expanded position to the retracted position.
19. A method of window-milling and sidetracking, the method
comprising: locating a position of a casing coupling in a borehole
using a locator apparatus; running a sidetracking assembly into the
borehole, wherein the sidetracking assembly comprises: a setting
tool; a whipstock comprising a ramp face along an axial length
thereof; and a drilling assembly having a drill bit disposed on an
end thereof; actuating the setting tool and securing the
sidetracking assembly in the borehole; applying weight on the
drilling assembly; rotating and translating the drill bit downward
along an axial length of the ramp face of the whipstock; milling a
window through the casing wall; and drilling into the formation in
a radially outward direction.
20. The method of claim 19, wherein locating a position of a casing
coupling in a borehole using a locator apparatus comprises:
disposing a locator apparatus into a borehole, the locator
apparatus comprising: a tool body having a central axis defined
therethrough; and at least one locator lug radially expandable from
the tool body, wherein the at least one locator lug is configured
to be received in an annular groove formed in an inner surface of a
casing string, wherein the at least one locator lug is configured
to move radially between a retracted position and an expanded
position; and moving the at least one locator lug between the
retracted position and the expanded position to indicate a casing
coupling location.
21. The method of claim 20, further comprising actuating the
locator apparatus at a predetermined location within the
borehole.
22. The method of claim 21, wherein actuating the locator apparatus
comprises moving the at least one locator lug from the retracted
position to the expanded position.
23. The method of claim 19, further comprising orienting the
whipstock in a desired azimuthal direction.
24. The method of claim 20, wherein the expanded position comprises
a first expanded position and a second expanded position.
25. The method of claim 24, wherein, in the first expanded
position, the at least one locator lug is engaged with the inner
surface of the casing.
26. The method of claim 24, wherein, in the second expanded
position, the at least one locator lug is engaged with the annular
groove formed in the inner surface of the casing.
27. The method of claim 20, further comprising determining a length
of the casing string within the borehole.
28. The method of claim 27, further comprising positioning the
locator apparatus at a predetermined distance from the drill bit
based on the determined length of the casing string within the
borehole.
29. The method of claim 20, further comprising deactuating the
locator apparatus at a predetermined location within the
borehole.
30. The method of claim 29, wherein deactuating the locator
apparatus comprises moving the at least one locator lug from the
expanded position to the retracted position.
31. A method of section milling, the method comprising: locating a
position of a casing coupling in a borehole using a locator
apparatus; running a section milling tool in to the borehole;
cutting a section of the casing; setting a cement plug in a
sectioned portion of the casing; and drilling a deviated hole using
a directional drilling assembly.
32. The method of claim 31, wherein locating a position of a casing
coupling in a borehole using a locator apparatus comprises:
disposing a locator apparatus into a borehole, the locator
apparatus comprising: a tool body having a central axis defined
therethrough; and at least one locator lug radially expandable from
the tool body, wherein the at least one locator lug is configured
to be received in an annular groove formed in an inner surface of a
casing string, wherein the at least one locator lug is configured
to move radially between a retracted position and an expanded
position; and moving the at least one locator lug between the
retracted position and the expanded position to indicate a casing
coupling location.
Description
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] Embodiments disclosed herein relate generally to downhole
tools.
[0003] Specifically, embodiments disclosed herein relate to an
expandable locator apparatus for locating a casing coupling in a
borehole.
[0004] 2. Background
[0005] Casing couplings, also referred to as casing joints or
casing collars, are used to connect lengths of casing pipe in a
borehole. Multiple lengths of casing pipe connected together with
casing couplings are referred to as a casing string. Coupling
locators are used to identify the location of couplings in borehole
casing strings. This is typically done during borehole departure
operations for various reasons. For example, the location of
couplings are determined prior to a window milling operation in a
sidetracking job to avoid having to mill through a coupling, which
has a larger metal wall cross-section as compared to a casing. The
integrity of the casing string above and below the casing coupling
may be lost, to some degree, by milling through the casing
coupling.
[0006] Traditionally, the locations of couplings are identified via
wireline logging tools, which are lowered into the borehole. The
cross-sectional area changes in the metal near the couplings are
typically identified using magnetic field sensors in the wireline
tools. The wireline techniques involve the use of dedicated
operators and equipment and considerable amount of time for a
dedicated wireline run. During such dedicated wireline runs, no
drilling activity can be conducted, thereby increasing the cost of
the drilling operation.
[0007] Casing coupling locators for use with wireline logging tools
include an electro-magnetic device capable of measuring changes in
a magnetic field. The electro-magnetic device is disposed within a
downhole tool and is typically lowered into the borehole while
being tethered to the surface by means of a wire or cable. This is
typically referred to as a wireline tool. The electro-magnetic
device measures the magnetic field at various positions within the
borehole, and the depth of the tool is determined using the length
of cable that has been lowered into the borehole. Casing couplings
usually have larger, metallic cross-sections as compared to the
rest of the casing string. This results in a change in the magnetic
field, which is recorded by the electro-magnetic device along with
the corresponding depth of the casing coupling.
[0008] Once a casing coupling is located, a setting tool and a
whipstock may be used to orient a drilling assembly above or below
the casing coupling. As such, the drilling assembly may avoid
drilling through the casing coupling, which usually has larger,
metallic cross-sections as compared to the rest of the casing
string, as discussed above. In operation, the whipstock is located
at a desired depth in the borehole by one of several techniques
(combined with an anchor or packer that can be set to a desired
location in a borehole, set on bottom, or set on plug, etc.), the
whipstock is then surveyed when at the desired depth so that the
whipstock face can be oriented azimuthally. Then the drilling
assembly is lowered into the borehole, e.g., the casing string, and
the whipstock serves to deflect or urge the drill bit into the side
wall of the bore hole at the angle of the ramp on the whipstock. A
window mill may be disposed on the drilling assembly within the
casing string and may follow the curve of the whipstock through the
casing wall, along a large radius path established by the
whipstock. Once the window mill has penetrated the casing wall and
created a window, the window mill is typically removed from the
borehole and replaced by a drill bit. As the drilling assembly
progresses, a secondary borehole is drilled that deviates or
branches from the existing borehole. This process of drilling a
deviated secondary borehole from an existing borehole is also
called "sidetracking." Another aspect of sidetracking includes
milling a section of casing, typically 15-25 ft., using Section
Mills, setting a cement plug, and using a directional drilling
assembly to drill a deviated hole from the existing borehole. The
Section Mills are expandable cutting tools commonly used to remove
a section of the casing. This process is known as "Section
Milling."
[0009] Wireline tools, as described above, require a dedicated
operation because they cannot be installed within a drill string.
This requires a significant portion of time dedicated to this
operation and also requires that all tools and drillstring
components are removed from the borehole. The operation also
requires dedicated, skilled operators trained to use the equipment.
This results in significant added cost to the drilling
operation.
[0010] Accordingly, there exists a need for a downhole coupling
locator tool that will efficiently locate casing couplings downhole
and reduce the downtime required to implement wireline locator
tools.
SUMMARY OF INVENTION
[0011] According to one aspect of the present invention, there is
provided a downhole locator apparatus, including a tool body having
a central axis defined therethrough, and at least one locator lug
radially expandable from the tool body, in which the at least one
locator lug is configured to be received in an annular groove
formed in an inner surface of a casing string, in which the at
least one locator lug is configured to move radially between a
retracted position and an expanded position.
[0012] According to another aspect of the present invention, there
is provided a method of locating a casing coupling in a borehole,
the method including disposing a locator apparatus into a borehole,
the locator apparatus including a tool body having a central axis
defined therethrough, and at least one locator lug radially
expandable from the tool body, in which the at least one locator
lug is configured to be received in an annular groove formed in an
inner surface of a casing string, in which the at least one locator
lug is configured to move radially between a retracted position and
an expanded position, and moving the at least one locator lug
between the retracted position and the expanded position to
indicate a casing coupling location.
[0013] According to another aspect of the present invention, there
is provided a method of window-milling and sidetracking, the method
including locating a position of a casing coupling in a borehole
using a locator apparatus, running a sidetracking assembly into the
borehole, in which the sidetracking assembly includes a setting
tool, a whipstock comprising a ramp face along an axial length
thereof, and a drilling assembly having a drill bit disposed on an
end thereof, actuating the setting tool and securing the
sidetracking assembly in the borehole, applying weight on the
drilling assembly, rotating and translating the drill bit downward
along an axial length of the ramp face of the whipstock, milling a
window through the casing wall; and drilling into the formation in
a radially outward direction.
[0014] According to another aspect of the present invention, there
is provided a method of section milling, the method including
locating a position of a casing coupling in a borehole using a
locator apparatus, running a section milling tool in to the
borehole, cutting at least a 25 ft. section of the casing, setting
a cement plug in a sectioned portion of the casing, and drilling a
deviated hole using a directional drilling assembly.
[0015] Other aspects and advantages of the present invention will
be apparent from the following description and the appended
claims.
BRIEF DESCRIPTION OF DRAWINGS
[0016] FIG. 1A is a side view of an expandable locator apparatus in
a retracted position in accordance with embodiments disclosed
herein.
[0017] FIG. 1B is a side view of an expandable locator apparatus in
a first expanded position in accordance with embodiments disclosed
herein.
[0018] FIG. 1C is a side view of an expandable locator apparatus in
a second expanded position in accordance with embodiments disclosed
herein.
[0019] FIGS. 2A-2C are side views of various locator lug profiles
in accordance with embodiments disclosed herein.
[0020] FIG. 3 is a flow chart of a method of window-milling and
sidetracking in accordance with embodiments disclosed herein.
[0021] FIG. 4 is a schematic view a sidetracking assembly in
accordance with embodiments disclosed herein.
DETAILED DESCRIPTION
[0022] The present disclosure relates to a locator apparatus for
locating a casing coupling in a borehole. More specifically,
embodiments disclosed herein relate to an expandable locator
apparatus for engaging with an annular groove formed in an inner
surface of a casing string to locate a casing coupling in a
borehole. Further, embodiments disclosed herein relate to a method
of window-milling and sidetracking.
[0023] Embodiments of an expandable locator apparatus disclosed
herein may be disposed on a bottom hole assembly (BHA) and may
allow casing couplings to be located while the BHA is still
disposed in the borehole. An expandable locator apparatus,
according to embodiments disclosed herein, may be able to ascertain
depth and mechanically locate the location or position of casing
couplings through the use of at least one locator lug, e.g. at
least one locator device such as a locator lug, pin, or protrusion.
While a locator lug is referred to herein, one having ordinary
skill in the art will appreciate that a pin, bolt, or other
protrusion member may be used without departing from the scope of
embodiments disclosed herein. Further, the at least one locator lug
of the expandable locator apparatus, according to embodiments
disclosed herein, may be coupled to at least one movable arm and
the at least one movable arm may be radially expandable from the
tool body. Furthermore, in one or more embodiments, the at least
one locator lug may be integrally formed with the at least one
movable arm or with a pad on the arm. In other embodiments, two or
more locator lugs and/or movable arms may be circumferentially
spaced around the tool body.
[0024] The expandable locator apparatus may be disposed within a
BHA containing additional tools and may be selectively actuated and
deactuated, as required. This may allow multiple operations to be
completed in a single run, thereby producing significant time and
cost savings. Additionally, the operation of the tool may not
require any additional equipment or resources, as the expandable
locator apparatus may use sensors and gauges found on a typical
drilling rig to produce the same information as a wireline tool,
which may have dedicated sensors and equipment. Finally, the
expandable locator apparatus may be operated by a skilled rig
operator, thereby eliminating the need for dedicated, wireline
personnel.
[0025] Referring generally to FIGS. 1A-1C, side views of an
expandable locator apparatus 100 according to embodiments disclosed
herein are shown. The expandable locator apparatus 100 includes a
tool body 101 having a central axis 150 formed therethrough. The
expandable locator apparatus 100 may include at least one locator
lug 105 that is radially expandable from the tool body 101. In one
or more embodiments, the at least one locator lug 105 may be
coupled to at least one movable arm 104. The at least one movable
arm 104 may be coupled to the tool body 101 and may be radially
expandable from the tool body 101. As used herein, "coupled" refers
to having two or more elements or components directly attached to
each other or indirectly attached to each other. For example,
although the at least one movable arm 104 is coupled to the tool
body 101, the at least one movable arm 104 may not necessarily need
to be in direct contact and directly attached to the tool body
101.
[0026] Further, as used herein, "radially expandable" refers to
having one or more elements or components being able to move in a
direction that is divergent from the central axis 150. For example,
the at least one locator lug 105 that is radially expandable from
the tool body 101 may move away from the tool body 101 in a
direction that is perpendicular or angled downward/upward to the
central axis 150. In one or more embodiments, the tool body 101 may
include at least one groove (not shown) configured to be received
by at least spline (not shown) that may be disposed on the at least
one movable arm 104. The engagement between the at least one groove
of the tool body 101 and the at least one spline of the at least
one movable arm may provide a track or path that may assist with
the radial expansion of the at least one movable arm 104.
[0027] In one or more embodiments, the expandable locator apparatus
100 may be disposed within a borehole (not shown). The borehole may
be lined with a casing string (not shown), which may include a
first length of casing 111 and a second length of casing 112. The
first length of casing 111 may be connected with the second length
of casing 112 by a casing coupling 110. As shown, the casing
coupling 110 is threadably connected to the first length of casing
111 and the second length of casing 112. However, those having
ordinary skill in the art will appreciate that other connecting
means may be used to connect a first length of casing to a second
length of casing. For example, the casing coupling may be connected
to a first length of casing and a second length of casing using
bolts, screws, or any other connection means known in the art. An
annular groove 121 may be formed in an inner surface of the casing
string, between the first length of casing 111 and the second
length of casing 112. The annular groove 121 may be a gap that is
formed near a center of the casing coupling 110, where the casing
coupling 110 connects the first length of casing 111 and the second
length of casing 112. In one or more embodiments, the at least one
locator lug 105 may be configured to move radially between a
retracted position and an expanded position, which will be
explained in further detail below. In one or more embodiments, the
at least one locator lug 105 may be configured to be received in
the annular groove 121.
[0028] In one or more embodiments, the expandable locator apparatus
100 may include an actuation mechanism (not shown) that may be
configured to move the at least one locator lug 105 and/or the at
least one movable arm 104 in a radial direction, between the
retracted position and the expanded position. Those having ordinary
skill in the art will appreciate that the at least one movable arm
104 may not be required to move the at least one locator lug in the
radial direction, between the retracted position and the expanded
position. For example, in one or more embodiments, the at least one
locator lug 105 may be coupled to the tool body 101 and be
configured to move in the radial direction between the retracted
position and the expanded position without the use of an at least
one movable arm.
[0029] In one or more embodiments, the actuation mechanism may be a
mechanical actuation mechanism, such as a spring or springs. The
springs may force the at least one locator lug 105 and/or the at
least one movable arm 104 in a radial direction away from the tool
body 101 and toward the inner surface of the casing string.
Alternatively, the actuation mechanism may be a hydraulic actuation
mechanism. For example, in one or more embodiments, the expandable
locator apparatus 100 may be actuated by a hydraulic pressure
differential between the expandable locator apparatus 100 and an
annulus 120 that is formed between an interior surface of the
casing string and the expandable locator apparatus 100. In other
words, a hydraulic force may cause the at least one locator lug 105
and/or the at least one movable arm 104 to move or extend
outwardly, in a radial direction that is away from the tool body
101, due to a differential pressure of the drilling fluid between
the expandable locator apparatus and the annulus 120. However,
those having ordinary skill in the art will appreciate that the
actuation mechanism may include other means known in the art to
move or force an element or component in the radial direction. For
example, the actuation mechanism may be an electrical-mechanical
actuation mechanism or an electro-hydraulic actuation
mechanism.
[0030] Referring to FIG. 1A, a side view of the expandable locator
apparatus 100 in the retracted position according to embodiments
disclosed herein is shown. In the retracted position, the at least
one locator lug 105 is not in contact with an inner surface of the
casing string, e.g. the first length of casing 111 or the second
length of casing 112. Further, in the retracted position, the at
least one locator lug 105 is not engaged with the annular groove
121 that may be formed about the casing coupling 110, between the
first length of casing 111 and the second length of casing 112. As
used herein, "retracted" may refer to any position in which the at
least one locator lug 105 and/or the at least one movable arm 104
is not in contact with the inner surface of the casing string and
is not engaged with the annular groove 121. For example, although
the at least one locator lug 105 and/or the at least one movable
arm 104 may not be completely retracted within the tool body 101,
the at least one locator lug 105 and/or the at least one movable
arm 104 may be considered to be in the retracted position as long
as the at least one locator lug 105 is not in contact with the
inner surface of the casing string and is not engaged with the
annular groove 121.
[0031] As shown in FIGS. 1B and 1C, respectively, the expanded
position may include a first expanded position and a second
expanded position. Referring to FIG. 1B, a side view of the
expandable locator apparatus 100 in a first expanded position
according to embodiments disclosed herein is shown. In the first
expanded position, the at least one locator lug 105 may be engaged
with an inner surface of the casing string, e.g., the first length
of casing 111 or the second length of casing 112. As discussed
above, the expandable locator apparatus 100 may be actuated, i.e.,
the at least one locator lug 105 may move or extend in a radial
direction that is away from the tool body 101, by an actuation
mechanism (not shown). In one or more embodiments, the at least one
locator lug 105 and/or the at least one movable arm may move or
extend outward, away from the tool body 101, until the movement of
the at least one locator lug 105 is restricted by an internal
diameter of the casing string, i.e., an internal surface of the
casing string. The expandable locator apparatus 100 may move within
the casing string, i.e., along the central axis 150, and the at
least one locator lug 105 may maintain contact with an internal
surface of the casing string due to hydraulic pressure acting on
the tool. As discussed above, the at least one locator lug 105
and/or the at least one movable arm 104 may be actuated,
alternatively, by a mechanical actuator, such as springs, which may
also cause the at least one locator lug 105 to maintain contact
with an internal surface of the casing string.
[0032] Referring to FIG. 1C, a side view of the expandable locator
apparatus 100 in a second expanded position according to
embodiments disclosed herein is shown. In the second expanded
position, the at least one locator lug 105 may be engaged with the
annular groove 121. As discussed above, the movement of the at
least one locator lug 105 is initially restricted by an internal
diameter of the casing string. As the expandable locator apparatus
100 moves within the casing string, the at least one locator lug
105 may maintain contact with an internal surface of the casing
string due to, for example, hydraulic pressure acting on the tool.
As the internal diameter of the casing string changes at the
location of the casing coupling 110, the hydraulic pressure may
force the at least one locator lug 105 and/or the at least one
movable arm 104 to move or extend further outward, away from the
tool body 101, until the at least one locator lug 105 is engaged in
the annular groove 121. As an operator may attempt to move the
expandable locator apparatus 100 past the annular groove 121, the
engagement of the at least one locator lug 105 and the annular
groove 121 may be observed by the operator as an increase in the
force required to move, e.g. pull or push, the expandable locator
apparatus 100 within the casing string.
[0033] Further, the expandable locator apparatus 100 may be
deactuated such that the at least one locator lug 105 moves from
the expanded position, either the first expanded position or the
second expanded position, to the retracted position. Deactuation of
the expandable locator apparatus 100 may allow the at least one
locator lug to disengage from the annular groove 121 and allow the
expandable locator apparatus 100 to move along the central axis 150
within the casing string. For example, deactuation may be achieved
by changing or relieving the hydraulic force between the expandable
locator apparatus 100 and the annulus 120 to allow the at least one
locator lug 105 to move from the expanded position to the retracted
position. Those having ordinary skill in the art will appreciate
that other methods of deactuation may be used with other types of
actuators and that deactuation is not limited to relieving the
hydraulic force acting on the at least one locator lug 105 and/or
the at least one movable arm 104, between the expandable locator
apparatus 100 and the annulus 120. Alternatively, in one or more
embodiments, the expandable locator apparatus 100 may not need to
deactuated in order for the at least one locator lug 105 to
disengage from the annular groove 121 and allow the expandable
locator apparatus 100 to move along the central axis 150 within the
casing string. For example, in one or more embodiments, springs
(not shown) may be used to move or extend the at least one locator
lug 105 in the radial direction, away from the tool body 101. Once
the at least locator lug 105 is engaged with the annular groove
121, a force with enough magnitude in a direction parallel with the
central axis 150 may cause the at least one locator lug 105 to
disengage from the annular groove 121 without full deactuation. The
force, described above, may cause the springs to compress as the at
least one locator lug 105 is forced out of engagement with the
annular groove 121. Once the expandable locator apparatus 100 is
deactuated, or when the at least one locator lug 105 is disengaged
from the annular groove 121, the operator may move, e.g., pull or
push, the expandable locator apparatus 100 along with a BHA and a
drillstring within the borehole, e.g. within a casing string, and
away from the casing coupling 110. This process may be repeated, as
required, at various points in the borehole to identify the
location of multiple casing couplings.
[0034] As shown in FIGS. 1A-1C, the at least one locator lug 105
may have a square or a rectangular profile. However, those having
ordinary skill in the art will appreciate that the profile of the
at least one locator lug may be one of a variety of shapes or
forms. For example, referring to FIGS. 2A-2C, in one or more
embodiments, at least one locator lug 205 may have at least a
square/rectangular profile, an angled/wedged profile, or a
round/semi-circular profile. As shown in FIG. 2A-2C, an annular
groove 221 may be formed in an inner surface of a casing string
(not shown) between a first length of casing 211 and a second
length of casing 212. In one or more embodiments, a casing coupling
210 may be used to connect the first length of casing 211 and the
second length of casing 212, as described above. Further, as
described above, the at least one locator lug 205 may be configured
to engage with the annular groove 221. As shown in FIG. 2A, in one
or more embodiments, the at least one locator lug 205 may have a
square or rectangular profile. As shown in FIG. 2B, in one or more
embodiments, the at least one locator lug 205 may have an angled,
or wedged, profile. This may allow the at least one locator lug 205
to be able to engage the annular groove 221 and also clear out any
debris that may have built up within the casing string and the
annular groove 221. Alternatively, as shown in FIG. 2C, in one or
more embodiments, the at least one locator lug may have a round or
semi-circular profile, which may allow the at least one locator lug
205 to disengage from the annular groove 221 without deactuation,
as discussed above. The at least one locator lug 205 may be round,
angled, triangular, hexagonal, or any other shape known in the
art.
[0035] A method of locating a casing coupling in a borehole, in
accordance with embodiments disclosed herein, may include disposing
a locator apparatus into a borehole, and moving at least one
locator lug between a retracted position and an expanded position
to indicate a casing coupling location. The locator apparatus may
include a tool body having a central axis defined therethrough, and
the at least one locator lug radially expandable from the tool
body, in which the at least one locator lug is configured to be
received in an annular groove formed in an inner surface of a
casing string, in which the at least one locator lug is configured
to move radially between the retracted position and the expanded
position. Once the at least one locator lug is engaged in the
annular groove, the operator receives an indication of the casing
coupling location, as an increase in the force required to move the
drill string, including the locator apparatus, within the casing
string.
[0036] The method may also include actuating the locator apparatus
at a predetermined location within the borehole. For example, as
discussed above, the locator apparatus may be a part of the BHA.
The BHA, i.e., the locator apparatus, may be moved within the
borehole to a location of interest, where the locator apparatus may
be actuated to locate a casing coupling at this location of
interest. This location of interest may be an area, e.g., a depth,
in a formation in which there is an interest in performing a
sidetracking operation. As such, the locator apparatus may be moved
to this location of interest, i.e., the predetermined location, in
order to locate a casing coupling at the predetermined location. As
discussed above, the borehole may be lined with multiple lengths of
casing, i.e., a casing string. Actuating the locator apparatus may
include moving the at least one locator lug from the retracted
position to the expanded position. As discussed above, the expanded
position may include a first expanded position and a second
expanded position. In the first expanded position, the at least one
locator lug may be engaged with the inner surface of the casing
string. In the second expanded position, the at least one locator
lug may be engaged with the annular groove formed in the inner
surface of the casing string. The method may also include
determining a length of the casing string within the borehole and
positioning the locator apparatus at a predetermined distance from
a drill bit based on the determined length of the casing string
within the borehole. For example, the length of the casing string
may be known by an operator operating the equipment by the number
of lengths of casing used in the casing string. The depth of the
drill bit, which is a known distance away from the locator
apparatus on the BHA, may be ascertained by actuating the locator
apparatus to locate a casing coupling to determine how many lengths
of casing are between the locator apparatus and the surface. The
method may also include deactuating the locator apparatus at a
predetermined location within the borehole. Deactuating the locator
apparatus may include moving the at least one locator lug from the
expanded position to the retracted position, as discussed
above.
[0037] A method of window-milling and sidetracking, according to
embodiments disclosed herein, may include locating a position of a
casing coupling in a borehole using a locator apparatus, running a
sidetracking assembly into the borehole, actuating the setting tool
and securing the sidetracking assembly in the borehole, applying
weight on a drilling assembly, rotating and translating a drill bit
downward along an axial length of a ramp face of a whipstock, and
deviating the drill bit in a radially outward direction, and
contacting an inner surface of a casing string to drill a deviated
hole. The sidetracking assembly may include a setting tool, a
whipstock including a ramp face along an axial length thereof, and
a drilling assembly having a drill bit disposed on an end thereof.
As discussed above, locating a position of a casing coupling in a
borehole, in accordance with embodiments disclosed herein, may
include disposing a locator apparatus into a borehole, and moving
the at least locator lug between a retracted position and an
expanded position to indicate a casing coupling location. The
locator apparatus may include a tool body having a central axis
defined therethrough, and at least one locator lug radially
expandable from the tool body, in which the at least one locator
lug is configured to be received in an annular groove formed in an
inner surface of a casing string, in which the at least one locator
lug is configured to move radially between the retracted position
and the expanded position. As discussed above, the length of the
casing string may be known by an operator operating the equipment
by the number of lengths of casing used in the casing string. The
depth of the drill bit, which is a known distance away from the
locator apparatus on the BHA, may be ascertained by actuating the
locator apparatus, i.e., moving the at least one locator lug
radially between the retracted position and the expanded position,
to locate a casing coupling and determining how many lengths of
casing are between the locator apparatus and the surface.
[0038] The method of window-milling and sidetracking may also
include actuating the locator apparatus at a predetermined location
within the borehole. The method of window-milling and sidetracking
may also include setting an orientation for the whipstock. For
example, a whipstock may be oriented in the borehole to a specific
orientation as measured by a measurement-while-drilling (MWD) tool.
As discussed above, the expanded position may include a first
expanded position and a second expanded position. In the first
expanded position, the at least one locator lug may be engaged with
the inner surface of the casing string. In the second expanded
position, the at least one locator lug may be engaged with the
annular groove formed in the inner surface of the casing string.
The method may also include determining a length of the casing
string within the borehole and positioning the locator apparatus at
a predetermined distance from a drill bit based on the determined
length of the casing string within the borehole. As discussed
above, once the at least one locator lug is engaged in the annular
groove, the operator receives an indication of the casing coupling
location, as an increase in the force required to move the drill
string, including the locator apparatus, within the casing string.
The operator may then determine the length of the casing string
within the borehole based on how many lengths of casing are between
the locator apparatus and the surface. Once the operator knows the
location of a casing coupling in an area of interest, the operator
may begin window-milling and/or sidetracking through a length of
casing or the borehole, and avoid window-milling or sidetracking
through a casing coupling. The method may also include deactuating
the locator apparatus at a predetermined location within the
borehole. Deactuating the locator apparatus may include moving the
at least one locator lug from the expanded position to the
retracted position, as discussed above.
[0039] A method of section milling, according to embodiments
disclosed herein, may include locating a position of a casing
coupling in a borehole using a locator apparatus, running a section
milling tool in to the borehole, cutting at least a 25 ft. section
of the casing, setting a cement plug in a sectioned portion of the
casing, and drilling a deviated hole using a directional drilling
assembly. The section milling tool may be expandable cutting tools
that may be used to remove a section of the casing. Those having
ordinary skill in the art will appreciate that the section milling
tool may be any cutting tool that may be used to remove a section
of a casing. Those having ordinary skill in the art will appreciate
that, in one or more embodiments, the section milling tool may be
used to cut a section that is more or less than 25 ft. in the
casing. A cement plug may be placed as a slurry in a specific
location within the borehole and may provide a means of pressure
isolation or a mechanical platform. Those having ordinary skill in
the art will appreciate that the cement plug may be any feature,
mechanism, or element known in the art that may provide a means of
isolation or provide a mechanical platform within a borehole.
[0040] The method of section milling, may also include disposing a
locator apparatus into a borehole, and moving the at least locator
lug between a retracted position and an expanded position to
indicate a casing coupling location. The locator apparatus may
include a tool body having a central axis defined therethrough, and
at least one locator lug radially expandable from the tool body, in
which the at least one locator lug is configured to be received in
an annular groove formed in an inner surface of a casing string, in
which the at least one locator lug is configured to move radially
between the retracted position and the expanded position.
[0041] Referring to FIG. 3, a flow chart of a method of
window-milling and sidetracking according to embodiments disclosed
herein is shown. A locator apparatus may be used to locate a
position of a casing coupling in a borehole, 361. Further, a
sidetracking assembly may be run into the borehole, 362. A setting
tool may be actuated to secure the sidetracking assembly within the
borehole, step 363. Further, weight may be applied to the drilling
assembly, 364. A drill bit may be rotated and translated downward
along an axial length of a ramp face of a whipstock, 365. A drill
bit may be deviated in a radially outward direction by contacting
the ramped face of the whipstock and may contact an inner surface
of a casing string to drill a deviated hole, 366.
[0042] Referring to FIG. 4, a schematic view a sidetracking
assembly 440, also known as a sidetracking BHA, according to
embodiments disclosed herein is shown. As shown in FIG. 4, the
sidetracking assembly 440 may include one or more of a setting
tool, e.g., an anchor 441, a whipstock 442, a drilling assembly 443
having a drill bit 453 or, alternatively, a mill (not shown)
disposed on an end thereof, a running tool 444, a segment of
heavyweight drill pipe 445, a circulation valve 446, an MWD tool
447 in addition to, or alternatively, a logging--while drilling
(LWD) tool (not shown), and an expandable locator apparatus 400.
Additionally, the sidetracking assembly 440 may include various
other elements or components. For example, the sidetracking
assembly 440 may include an expandable reamer assembly (not shown).
For example, and without limitation, exemplary expandable reamer
assemblies are shown in U.S. Pat. No. 6,732,817 and U.S. Pat. No.
7,048,078, which are incorporated herein by reference in their
entirety. Both U.S. Pat. No. 6,732,817 and U.S. Pat. No. 7,048,078
are assigned to the assignee of the present application. Further,
the sidetracking assembly 440 may include a scraper apparatus (not
shown). The scraper apparatus may be used to scrape or remove
debris that may build up within the casing string. Those having
ordinary skill in the art will appreciate that the sidetracking
assembly 440 may not necessarily be used exclusively for
sidetracking purposes, and that the sidetracking assembly 440, or
components of the sidetracking assembly 440, may be used to drill
the borehole. For example, the whipstock 442 may be excluded from
the sidetracking assembly 440, and the remaining components of the
sidetracking assembly 440 may be used to drill the borehole.
[0043] Still referring to FIG. 4, the sidetracking assembly 440 may
be run into a borehole (not shown), which may be lined with a
casing string (not shown), and the expandable locator apparatus 400
may locate a position or location of a casing coupling (not shown),
as described above. The anchor 441 may be set and may secure the
sidetracking assembly 440 within the borehole. The anchor 441 may
be an expandable anchor, or packer, that may inflate or expand in
order to secure the sidetracking assembly 440 within the borehole.
However, those having ordinary skill in the art will appreciate
that various other types of anchors or packers known in the art may
be used to secure the sidetracking assembly 440 within the
borehole. Weight may be applied to the drilling assembly 443 by,
for example, the segment of heavyweight drill pipe 445, as well as
by additional components, such as the running tool 444, the
circulation valve 446, and the MWD tool 447. The drill bit 453 of
the drilling assembly 443 may rotate and translate along an axial
length of a ramp face of the whipstock 442 and allow the drill bit
453 to deviate radially outward and contact an inner surface of a
casing string to drill a deviated hole. Those having ordinary skill
in the art will appreciate that the drill bit 453 may be a window
mill (not shown) that may be used to mill a window in the casing
string and may be removed, once the window is milled, and replaced
with a drill bit to complete a sidetracking process. The window
mill may be substantially similar to a drill bit, and may translate
along an axial length of a ramp face of the whipstock 442 to mill a
window in the casing string. Although the expandable locator
apparatus 400 is shown to be above the anchor 441 in the exemplary
sidetracking assembly 440 shown in FIG. 4, those having ordinary
skill in the art will appreciate that, in one or more embodiments,
the expandable locator apparatus 400 may be located below the
anchor 441. Further, those having ordinary skill in the art will
appreciate that the expandable locator apparatus 400 may be used
before or after the scraper apparatus, discussed above, is used. As
discussed above, one or more embodiments of the expandable locator
apparatus may include angled or wedged locator lugs that may assist
in clearing any debris build-up that may occur within an interior
surface of a casing string.
[0044] Advantageously, embodiments disclosed herein may provide an
expandable locator apparatus that may be able to ascertain depth
and mechanically locate the location or position of casing
couplings through the use of at least one locator lug. The
expandable locator apparatus may be disposed within a BHA
containing additional tools and may be selectively actuated and
deactuated, as required. This may allow multiple operations to be
completed in a single run, thereby producing significant time and
cost savings. Additionally, the operation of the tool may not
require any additional equipment or resources, as the expandable
locator apparatus may use sensors and gauges found on a typical
drilling rig, such as pressure, force, and temperature gauges, to
produce the same information as a wireline tool, which may have
dedicated sensors and equipment. Finally, the expandable locator
apparatus may be operated by a skilled rig operator, thereby
eliminating the need for dedicated, wireline personnel.
[0045] While embodiments have been described with respect to a
limited number of embodiments, those skilled in the art, having
benefit of this disclosure, will appreciate that other embodiments
can be devised which do not depart from the scope of embodiments
disclosed herein. Accordingly, the scope of embodiments disclosed
herein should be limited only by the attached claims.
* * * * *