U.S. patent application number 14/452262 was filed with the patent office on 2015-03-05 for retractable collet assembly for liner string installation in a wellbore.
This patent application is currently assigned to HALLIBURTON ENERGY SERVICES, INC.. The applicant listed for this patent is Halliburton Energy Services, Inc.. Invention is credited to Wesley Paul Dietz, Lester Barett Dupler, Dan Saurer, David Joe Steele.
Application Number | 20150060049 14/452262 |
Document ID | / |
Family ID | 52581516 |
Filed Date | 2015-03-05 |
United States Patent
Application |
20150060049 |
Kind Code |
A1 |
Saurer; Dan ; et
al. |
March 5, 2015 |
Retractable Collet Assembly for Liner String Installation in a
Wellbore
Abstract
A collet assembly for installing a liner string having a profile
in a wellbore. The collet assembly has a generally cylindrical
collet collar with a plurality of collet fingers extending
therefrom each having a collet head on a distal end thereof. In a
first position, the collet fingers are in a radially outwardly
flexed state such that the collet finger extend substantially
parallel with the central axis of the collet collar. In a second
position, the collet fingers are in a radially relaxed state such
that the collet fingers extend from the collet collar to the collet
heads at an angle toward the central axis of the collet collar.
Inventors: |
Saurer; Dan; (Plano, TX)
; Steele; David Joe; (Arlington, TX) ; Dietz;
Wesley Paul; (Carrollton, TX) ; Dupler; Lester
Barett; (Providence Village, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Halliburton Energy Services, Inc. |
Houston |
TX |
US |
|
|
Assignee: |
HALLIBURTON ENERGY SERVICES,
INC.
Houston
TX
|
Family ID: |
52581516 |
Appl. No.: |
14/452262 |
Filed: |
August 5, 2014 |
Current U.S.
Class: |
166/241.1 |
Current CPC
Class: |
E21B 23/00 20130101 |
Class at
Publication: |
166/241.1 |
International
Class: |
E21B 19/08 20060101
E21B019/08; E21B 19/24 20060101 E21B019/24; E21B 19/06 20060101
E21B019/06 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 4, 2013 |
US |
PCT/US2013/058056 |
Claims
1. A collet assembly for releasably engaging a profile of a
downhole tubular, the collet assembly comprising: a generally
cylindrical collet collar having a central axis; and a plurality of
collet fingers extending from the collet collar each having a
collet head on a distal end thereof; and wherein, in a first
configuration, the collet fingers are in a radially outwardly
flexed state such that the collet finger extend substantially
parallel with the central axis of the collet collar; and wherein,
in a second configuration, the collet fingers are in a radially
relaxed state such that the collet fingers extend from the collet
collar to the collet heads at an angle toward the central axis of
the collet collar.
2. The collet assembly as recited in claim 1 wherein the collet
fingers are angled between about 2 degrees and about 6 degrees
toward the central axis of the collet collar when the collet
fingers are in the radially relaxed state.
3. The collet assembly as recited in claim 1 wherein the collet
fingers are angled at least 3 degrees toward the central axis of
the collet collar when the collet fingers are in the radially
relaxed state.
4. The collet assembly as recited in claim 1 wherein the collet
fingers are operable to be radially inwardly
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119 of the filing date of International Application No.
PCT/US2013/058056, filed Sep. 4, 2013.
TECHNICAL FIELD OF THE DISCLOSURE
[0002] This disclosure relates, in general, to equipment utilized
in conjunction with operations performed in relation to
subterranean wells and, in particular, to liner running tool having
a retractable collet assembly for installing a liner string in a
wellbore.
BACKGROUND
[0003] Without limiting the scope of the present invention, its
background is described with reference to constructing a
subterranean well, as an example.
[0004] In conventional practice, the drilling of an oil or gas well
involves creating a wellbore that traverses numerous subterranean
formations. For a variety reasons, each of the formations through
which the well passes is preferably sealed. For example, it is
important to avoid an undesirable passage of formation fluids,
gases or materials out of a formation and into the wellbore or for
wellbore fluids to enter a formation. In addition, it is commonly
desired to isolate producing formations from one another and from
nonproducing formations.
[0005] Accordingly, conventional well architecture typically
includes the installation of casing within the wellbore. In
addition to providing the sealing function, the casing also
provides wellbore stability to counteract the geomechanics of the
formation such as compaction forces, seismic forces and tectonic
forces, thereby preventing the collapse of the wellbore wall. The
casings are generally fixed within the wellbore by a cement layer
between the outer wall of the casing and the wall of the wellbore.
During the drilling of the wellbore, annuli are provided between
the outer surfaces of the casings and the wellbore wall. When a
casing string is located in its desired position in the well, a
cement slurry is pumped via the interior of the casing, around the
lower end of the casing and upwards into the annulus. As soon as
the annulus around the casing is sufficiently filled with the
cement slurry, the cement slurry is allowed to harden. The cement
sets up in the annulus, supporting and positioning the casing and
forming a substantially impermeable barrier.
[0006] In one approach, each casing string extends downhole from
the surface such that only a lower section of each casing string is
adjacent to the wellbore wall. Alternatively, the wellbore casings
may include one or more liner strings, which do not extend to the
surface of the wellbore, but instead typically extend from near the
bottom end of a previously installed casing downward into the
uncased portion of the wellbore. In such installations, the liner
string may be set or suspended from a liner hanger. As yet another
alternative, in some wellbore installations, a liner string may be
installed in an uncased portion of the wellbore without being set
or suspended from a liner hanger. Liner strings are typically
lowered downhole on a work string that may include a running tool
that attaches to the liner string. It has been found, that in
certain wellbores such as deviated wellbores, horizontal wellbores,
multilateral wellbores and the like, significant force may be
required to work the liner string to the bottom of the wellbore. In
addition, it has been found, that following liner string
installation in such wellbores, it is sometimes difficult to
retrieve the running tool out of the wellbore due to certain
components of the running tool, such as collet assemblies, hanging
up on profiles of the installed liner string.
[0007] Accordingly, a need has arisen for a running tool that is
operable to deliver the required force to work the liner string to
the bottom of the wellbore. In addition, a need has arisen for such
a running tool that is operable to be retrieved out of the wellbore
without hanging up on profiles of the installed liner string.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] For a more complete understanding of the features and
advantages of the present disclosure, reference is now made to the
detailed description along with the accompanying figures in which
corresponding numerals in the different figures refer to
corresponding parts and in which:
[0009] FIG. 1 is a schematic illustration of an offshore oil and
gas platform installing a liner string in a subterranean wellbore
according to an embodiment of the present disclosure;
[0010] FIG. 2A is a side view of a portion of a running tool in its
running configuration for installing a liner string in a
subterranean wellbore according to an embodiment of the present
disclosure;
[0011] FIG. 2B is a quarter sectional view of a portion of a
running tool in its running configuration positioned in a liner
string according to an embodiment of the present disclosure;
[0012] FIG. 3A is a side view of a portion of a running tool in its
retrieval configuration after installing a liner string in a
subterranean wellbore according to an embodiment of the present
disclosure;
[0013] FIG. 3B is a quarter sectional view of a portion of a
running tool in its retrieval configuration after disengaging from
a liner string according to an embodiment of the present
disclosure; and
[0014] FIGS. 4A-4B are cross sectional views of a collet assembly
for use in a running tool according to an embodiment of the present
disclosure in its flexed and relaxed states, respectively.
DETAILED DESCRIPTION
[0015] While various system, method and other embodiments are
discussed in detail below, it should be appreciated that the
present disclosure provides many applicable inventive concepts,
which can be embodied in a wide variety of specific contexts. The
specific embodiments discussed herein are merely illustrative, and
do not delimit the scope of the present disclosure.
[0016] The present disclosure is directed to a running tool that is
operable to deliver the required force to work a liner string to
the bottom of a wellbore. In addition, the running tool that of the
present disclosure is operable to be retrieved out of the wellbore
without hanging up on profiles of the installed liner string.
[0017] In a first aspect, the present disclosure is directed to a
running tool for installing a liner string having a profile in a
wellbore. The running tool includes a mandrel, a prop assembly
positioned about the mandrel and a collet assembly slidably
positioned on the mandrel. The collet assembly has a generally
cylindrical collet collar with a plurality of collet fingers
extending therefrom each having a collet head on a distal end
thereof. In a first position of the collet assembly relative to the
mandrel, the prop assembly radially outwardly flexes the collet
fingers such that the collet heads engage the profile of the liner
string and are operable to apply a force in the downhole direction
to the liner string. In a second position of the collet assembly
relative to the mandrel, the collet assembly is remote from the
prop assembly such that the collet fingers radially inwardly
contract disengaging the collet heads from the profile of the liner
string, thereby enabling removal of the running tool from the liner
string.
[0018] In one embodiment of the running tool, in the second
position of the collet assembly relative to the mandrel, an inner
surface of the collet heads is proximate the mandrel forming
clearance gaps therebetween. In another embodiment, in the second
position of the collet assembly relative to the mandrel, an inner
surface of the collet heads contacts the mandrel. In certain
embodiments of the running tool, in the second position of the
collet assembly relative to the mandrel, the collet fingers are
angled toward the mandrel from the collet collar to the collet
heads. In such embodiments, collet fingers may be angled between
about 2 degrees and about 6 degrees or the collet fingers may be
angled at least 3 degrees. In some embodiments of the running tool,
in the first position of the collet assembly relative to the
mandrel, the collet fingers are in a first radially outwardly
flexed state and in the second position of the collet assembly
relative to the mandrel, the collet fingers are in a second
radially outwardly flexed state that is less than the first
radially outwardly flexed state. In other embodiments of the
running tool, in the first position of the collet assembly relative
to the mandrel, the collet fingers are in the radially outwardly
flexed state and in the second position of the collet assembly
relative to the mandrel, the collet fingers are in a radially
relaxed state. In these embodiments, in the second position of the
collet assembly relative to the mandrel, the collet fingers may be
operable to be radially inwardly flexed to contact an inner surface
of the collet heads with the mandrel.
[0019] In a second aspect, the present disclosure is directed to a
method for installing a liner string with a profile in a wellbore.
The method includes lowering the liner string into the wellbore on
a running tool, the running tool including a mandrel, a prop
assembly positioned about the mandrel and a collet assembly
slidably positioned on the mandrel, the collet assembly having a
generally cylindrical collet collar with a plurality of collet
fingers extending therefrom each having a collet head on a distal
end thereof; engaging the collet heads in the profile of the liner
string by radially outwardly flexing the collet fingers with the
prop assembly; applying a force in the downhole direction to the
liner string with the collet assembly; positioning the liner string
at a desired location in the wellbore; disengaging the collet heads
from the profile of the liner string by unpropping the collet
assembly such that the collet fingers radially inwardly contract;
and removing the running tool from the liner string.
[0020] The method may also include lowering the running tool
downhole into the liner string, locating an inner surface of the
collet heads proximate to the mandrel forming clearance gaps
therebetween, contacting an inner surface of the collet heads with
the mandrel; positioning the collet fingers at an angle toward the
mandrel from the collet collar to the collet heads; placing the
collet fingers in a reduced radially outwardly flexed state;
placing the collet fingers in a radially relaxed state; and/or
radially inwardly flexing the collet fingers to contact an inner
surface of the collet heads with the mandrel.
[0021] In a third aspect, the present disclosure is directed to a
collet assembly for releasably engaging a profile of a downhole
tubular. The collet assembly includes a generally cylindrical
collet collar having a central axis and a plurality of collet
fingers extending from the collet collar each having a collet head
on a distal end thereof. In a first configuration, the collet
fingers are in a radially outwardly flexed state such that the
collet fingers extend substantially parallel with the central axis
of the collet collar. In a second configuration, the collet fingers
are in a radially relaxed state such that the collet fingers extend
from the collet collar to the collet heads at an angle toward the
central axis of the collet collar.
[0022] In certain embodiments of the second configuration, the
collet fingers are angled between about 2 degrees and about 6
degrees toward the central axis of the collet collar when the
collet fingers are in the radially relaxed state. In some
embodiments of the second configuration, the collet fingers are
angled at least 3 degrees toward the central axis of the collet
collar when the collet fingers are in the radially relaxed state.
In one embodiment of the second configuration, the collet fingers
are operable to be radially inwardly flexed when the collet fingers
are in the radially relaxed state.
[0023] Referring initially to FIG. 1, a running tool for installing
a liner string in a subterranean wellbore is being deployed from an
offshore oil or gas platform that is schematically illustrated and
generally designated 10. A semi-submersible platform 12 is centered
over submerged oil and gas formation 14 located below sea floor 16.
A subsea conduit 18 extends from deck 20 of platform 12 to wellhead
installation 22, including blowout preventers 24. Platform 12 has a
hoisting apparatus 26, a derrick 28, a travel block 30, a hook 32
and a swivel 34 for raising and lowering pipe strings, such as a
liner string 36.
[0024] A main wellbore 38 has been drilled through the various
earth strata including formation 14. The terms "parent" and "main"
wellbore are used herein to designate a wellbore from which another
wellbore is drilled. It is to be noted, however, that a parent or
main wellbore does not necessarily extend directly to the earth's
surface, but could instead be a branch of yet another wellbore. A
casing string 40 is secured within main wellbore 38 by cement 42.
The term "casing" is used herein to designate a tubular string used
in a wellbore or to line a wellbore. The casing may be of the type
known to those skilled in the art as a "liner" and may be made of
any material, such as steel or a composite material and may be
segmented or continuous, such as coiled tubing.
[0025] Casing string 38 includes a window joint 44 interconnected
therein. In addition, casing string 38 includes a latch coupling
46. Latch coupling 46 has a latch profile that is operably
engagable with latch keys of a latch assembly 48 such that latch
assembly 48 may be axially anchored and rotationally oriented in
latch coupling 46. In the illustrated embodiment, when the primary
latch key of latch assembly 48 has operably engaged the latch
profile of latch coupling 46, a deflection assembly depicted as
whipstock 50 is positioned in a desired circumferential orientation
relative to window joint 44 such that a window can be milled,
drilled or otherwise formed in window joint 44 in the desired
circumferential direction. As illustrated, a branch or lateral
wellbore 52 has been drilled from window joint 44 of main wellbore
38. The terms "branch" and "lateral" wellbore are used herein to
designate a wellbore that is drilled outwardly from its
intersection with another wellbore, such as a parent or main
wellbore. A branch or lateral wellbore may have another branch or
lateral wellbore drilled outwardly therefrom.
[0026] Liner string 36 is being lowered downhole on a work string
54 that includes a running tool 56 that attaches work string 54 to
liner string 36. As shown, liner string 36 is being positioned in
lateral wellbore 52 that is generally horizontal. Due to friction
between liner string 36 and the surface of lateral wellbore 52,
significant force may be required to push liner string 36 to the
bottom or toe of lateral wellbore 52. This is achieved by applying
a force in the downhole direction to liner string 36 with a collet
assembly of running tool 56 that engages a profile within liner
string 36. After liner string 36 is positioned at a desired
location in wellbore 52, the collet assembly disengages from the
profile, which enables running tool 56 to be retrieved to the
surface with work string 54.
[0027] Even though FIG. 1 depicts a liner string being installed in
a horizontal wellbore, it should be understood by those skilled in
the art that the present running tool is equally well suited for
use in wellbores having other orientations including vertical
wellbores, slanted wellbores, deviated wellbores or the like.
Accordingly, it should be understood by those skilled in the art
that the use of directional terms such as above, below, upper,
lower, upward, downward, uphole, downhole and the like are used in
relation to the illustrative embodiments as they are depicted in
the figures, the upward direction being toward the top of the
corresponding figure and the downward direction being toward the
bottom of the corresponding figure, the uphole direction being
toward the surface of the well, the downhole direction being toward
the toe of the well. Also, even though FIG. 1 depicts an offshore
operation, it should be understood by those skilled in the art that
the present running tool is equally well suited for use in onshore
operations.
[0028] Referring next to FIGS. 2A-2B, therein is depicted a section
of a running tool 100 for installing a liner string in a
subterranean wellbore. As best seen in FIG. 2B, a liner string 102
may include any number of substantially tubular sections that are
preferably formed from jointed tubulars that are threadably coupled
together at the surface. In the illustrated section, liner string
102 includes an upper liner tubular 104 and an intermediate liner
tubular 106 that are threadably coupled together at threaded
connection 108. In the illustrated embodiment, liner string 102
defines a profile 110 between an upper shoulder 112 of intermediate
liner tubular 106 and a lower shoulder 114 of upper liner tubular
104. Running tool 100 is positioned at least partially within liner
string 102 and is operable to transport, apply downward force on
and set liner string 102 in the wellbore. Running tool 100 includes
a plurality of substantially tubular members that may be referred
to as a generally tubular mandrel 116 that cooperate together to
form a central bore 118 extending throughout. In the illustrated
section, tubular mandrel 116 includes an upper mandrel tubular 120
that may be threadably and sealingly coupled to or operably
associated with other components of the work string at its upper
end. Upper mandrel tubular 120 is threadably coupled on it lower
end to an intermediate mandrel tubular 122. Upper mandrel tubular
120 has a radially expanded lower section 124 that defines an upper
shoulder 126. Upper mandrel tubular 120 also has a radially reduced
channel 128.
[0029] A prop assembly 130 including a prop extension 132 is
disposed around upper mandrel tubular 120. A snap ring 134 prevents
axial movement of prop assembly 130 beyond predetermined limits
along upper mandrel tubular 120. A collet assembly 136 is slidably
positioned around upper mandrel tubular 120. Collet assembly 136
includes a generally cylindrical collet collar 138 having a
plurality of collet fingers 140 extending therefrom each having a
collet head 142 on a distal end thereof. Collet heads 142 include
lower shoulders 144 that form a mating surface with upper shoulder
112 of intermediate liner tubular 106. In addition, collet heads
142 include upper shoulders 146 that form a mating surface with
lower shoulder 114 of upper liner tubular 104. Collet collar 138
has a lower shoulder 148.
[0030] In operation and additionally referencing FIGS. 3A-3B,
running tool 100 is used to install liner string 102 in a wellbore.
In the illustrated embodiment, as liner string 102 is being run
downhole via work string 54, significant force may be required to
push liner string 102 to its desired location, particularly in
deviated, horizontal or multilateral wellbores. The force from the
surface is applied through work string 54 to upper mandrel tubular
120. In the running configuration of running tool 100, upper
mandrel tubular 120 applies the downward force to intermediate
liner tubular 106 via collet assembly 136. Specifically, as best
seen in FIG. 2B, prop assembly 130 radially outwardly flexes collet
fingers 140 such that collet heads 142 engage profile 110 of liner
string 102. In this configuration, the downward force from upper
mandrel tubular 120 is applied to upper shoulder 112 of
intermediate liner tubular 106 by lower shoulders 144 of collet
heads 142.
[0031] Once liner string 102 is positioned in the desired location
in the wellbore, running tool 100 can be decoupled from liner
string 102 and retrieved to the surface. This may be accomplished
using hydraulic pressure, shear force, string rotation or a
combination thereof to decouple a lower collet (not pictured) or
other component to allow relative movement between mandrel 116 and
liner string 102. Thereafter, shifting mandrel 116 uphole relative
to liner string 102 unprops collet assembly 136 through the
interaction of lower shoulder 114 of upper liner tubular 104 with
upper shoulders 146 of collet heads 142. Once collets heads 142 are
off of or remote from prop extension 132 of prop assembly 130, as
best seen in FIG. 3B, collet fingers 140 radially inwardly contract
such that an inner surface of collet heads 142 is proximate to the
outer surface of upper mandrel tubular 120 forming clearance gaps
therebetween or in contact with the outer surface of upper mandrel
tubular 120. In the case of contact between the inner surface of
collet heads 142 and the outer surface of upper mandrel tubular
120, collet fingers 140 go from a first radially outwardly flexed
state supported by prop extension 132 to a second radially
outwardly flexed state supported by upper mandrel tubular 120,
wherein the first radially outwardly flexed state is greater than
the second radially outwardly flexed state. In the case of a
proximate relationship between the inner surface of collet heads
142 and the outer surface of upper mandrel tubular 120, collet
fingers 140 go from a radially outwardly flexed state supported by
prop extension 132 to radially relaxed state, wherein a radially
inwardly directed force could cause collet fingers 140 to be
radially inwardly flexed until the inner surface of collet heads
142 contacts upper mandrel tubular 120. Depending upon the desired
relationship between the inner surface of collet heads 142 and the
outer surface of upper mandrel tubular 120, collet fingers 140 may
be angled toward upper mandrel tubular 120 from collet collar 138
to collet heads 142 between about 2 degrees and about 6 degrees and
preferably at least 3 degrees.
[0032] In this radially refracted configuration of collet assembly
136, collet heads 142 have disengaged from mating profile 110,
thereby releasing running tool 100 from liner string 102.
Thereafter, running tool 100 may be withdrawn uphole from liner
string 102 and out of the wellbore. Importantly, due to the
radially contracted configuration of collet assembly 136, running
tool 100 can be retrieved out of the wellbore without collet heads
140 hanging up on profiles or other radially reduced regions of
liner string 102. In addition, running tool 100 may be lowered
further into downhole into liner string 102, if desired, without
collet heads 140 hanging up on profiles or other radially reduced
regions of liner string 102.
[0033] Referring next to FIGS. 4A-4B, therein are depicted cross
sectional views of a collet assembly in its radially outwardly
flexed state and its relaxed state, respectively. Collet assembly
136 includes a generally cylindrical collet collar 138 having a
central axis 150. Collet assembly 136 also includes a plurality of
collet fingers 140 that extend from collet collar 138. Each collet
finger 140 has a collet head 142 on a distal end thereof. Collet
heads 142 include lower shoulders 144 for mating with upper
shoulder 112 of intermediate liner tubular 106, as described above.
In addition, collet heads 142 include upper shoulders 146 for
mating with lower shoulder 114 of upper liner tubular 104, as
described above. Collet collar 138 has a lower shoulder 148. Collet
assembly 136 has a first configuration, in which collet fingers 140
are in a radially outwardly flexed state such that collet fingers
140 extend substantially parallel with central axis 150 of collet
collar 138, as best seen in FIG. 4A. This configuration corresponds
to the configuration in FIG. 2B wherein collet assembly 136 is
engaged in profile 110 of liner string 102. Collet assembly 136 has
a second configuration, in which collet fingers 140 are in a
radially relaxed state such that collet fingers 140 extend from
collet collar 138 to collet heads 142 at an angle toward central
axis 150, as best seen in FIG. 4B. This configuration corresponds
to the configuration in FIG. 3B wherein collet assembly 136 is
disengaged from profile 110 of liner string 102. In this
illustrated embodiment, collet fingers 140 are angle toward central
axis 150 at about 3 degrees, however, other angles both greater
than and less than 3 degrees are also possible and are considered
within the scope of the present disclosure including, but not
limited to angles between about 2 degrees and about 6 degrees.
[0034] It should be understood by those skilled in the art that the
illustrative embodiments described herein are not intended to be
construed in a limiting sense. Various modifications and
combinations of the illustrative embodiments as well as other
embodiments will be apparent to persons skilled in the art upon
reference to this disclosure. It is, therefore, intended that the
appended claims encompass any such modifications or
embodiments.
* * * * *