U.S. patent application number 12/925319 was filed with the patent office on 2011-02-17 for expandable packer system.
Invention is credited to Mark K. Adam, Keven O'Connor, Jeffrey C. Williams.
Application Number | 20110037230 12/925319 |
Document ID | / |
Family ID | 40094795 |
Filed Date | 2011-02-17 |
United States Patent
Application |
20110037230 |
Kind Code |
A1 |
O'Connor; Keven ; et
al. |
February 17, 2011 |
Expandable packer system
Abstract
The expandable casing packing element systems for cased and
open-hole wellbores include an expandable casing member having a
sealing device comprising a sealing element disposed between at
least two retainer rings. The retainer rings have flat
cross-sections and the sealing element is forced radially outward
by the expansion of the expandable casing against the two retainer
rings such that the sealing element protrudes outwardly beyond the
retainer rings and engages the wall of a wellbore in three
locations. The retainer rings can also include flares that extend
outwardly from the body of the expandable casing to which they are
attached. As the expandable casing is expanded, the flares are
forced inward to compress the sealing element which is then
extruded radially outward through a gap between the two retainer
rings to engage and seal off the wellbore.
Inventors: |
O'Connor; Keven; (Houston,
TX) ; Adam; Mark K.; (Houston, TX) ; Williams;
Jeffrey C.; (Cypress, TX) |
Correspondence
Address: |
GREENBERG TRAURIG (HOU);INTELLECTUAL PROPERTY DEPARTMENT
1000 Louisiana Street, Suite 1700
Houston
TX
77002
US
|
Family ID: |
40094795 |
Appl. No.: |
12/925319 |
Filed: |
October 19, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12592491 |
Nov 25, 2009 |
7845402 |
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12925319 |
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12156408 |
May 30, 2008 |
7703542 |
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12592491 |
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60933183 |
Jun 5, 2007 |
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Current U.S.
Class: |
277/336 |
Current CPC
Class: |
E21B 43/103 20130101;
E21B 33/10 20130101 |
Class at
Publication: |
277/336 |
International
Class: |
E21B 33/12 20060101
E21B033/12 |
Claims
1-20. (canceled)
21. A sealing device for a radially expandable casing, the sealing
device comprising: a first retainer ring comprising a first end
portion and a second end; a second retainer ring; a gap disposed
between the first retainer ring and the second retainer ring; and
an extrudable sealing element disposed between the first retainer
ring and the second retainer ring and in fluid communication with
the gap, the extrudable sealing element being extrudable through
the gap when the expandable casing is radially expanded from a
first position to a second position, wherein during expansion of
the expandable casing toward the second position, the second end
portion of the first retainer ring is moved with respect to an
outer wall surface of the expandable casing toward an axis of the
expandable casing.
22. The sealing device of claim 21, wherein the second retainer
ring comprising a second retainer ring first end portion and a
second retainer ring second end portion, and wherein during
expansion of the expandable casing toward the second position, the
second retainer ring second end portion of the second retainer ring
is moved with respect to an outer wall surface of the expandable
casing toward the axis of the expandable casing.
23. A sealing device for a radially expandable casing, the sealing
device comprising: a first retainer ring comprising a first end
portion disposed substantially parallel to an axis of the
expandable casing and a second end portion disposed at a first
initial angle relative to the first end portion, the first initial
angle being less than 90 degrees and more than 0 degrees; a second
retainer ring; a gap disposed between the first retainer ring and
the second retainer ring; and an extrudable sealing element
disposed between the first retainer ring and the second retainer
ring and in fluid communication with the gap, the extrudable
sealing element being extrudable through the gap when the
expandable casing is radially expanded from a first position to a
second position, wherein during expansion of the expandable casing
toward the second position, the first initial angle is reduced.
24. The sealing device of claim 23, wherein the second retainer
ring comprises a second retainer ring first end portion disposed
substantially parallel to the axis of the expandable casing and a
second retainer ring second end portion disposed at a second
initial angle relative to the second retainer ring first end
portion, the second initial angle being less than 90 degrees and
more than 0 degrees; wherein during expansion of the expandable
casing toward the second position, the second initial angle is
reduced.
25. A sealing device for a radially expandable casing, the sealing
device comprising: a first retainer ring; a second retainer ring; a
gap disposed between the first retainer ring and the second
retainer ring; and an extrudable sealing element disposed between
the first retainer ring and the second retainer ring and in fluid
communication with the gap, the extrudable sealing element being
extrudable through the gap when the expandable casing is radially
expanded from a run-in casing radius to a set casing radius, the
set casing radius being greater than the run-in casing radius and
the difference between the set casing radius and the run-in casing
radius defining a casing radius differential, wherein during
expansion of the expandable casing, a portion of the first retainer
ring is radially expanded outward from a first run-in ring radius,
as measured from an axis of the expandable casing to the portion of
the first retainer ring, to a first set ring radius, as measured
from the axis of the expandable casing to the portion of the first
retainer ring, the first set ring radius being greater than the
first run-in ring radius, and the difference between the first set
ring radius and the first run-in ring radius defining a first ring
radius differential, and wherein the casing radius differential is
greater than the first ring radius differential.
26. The sealing device of claim 25, wherein during expansion of the
expandable casing, a portion of the second retainer ring is
radially expanded outward from a second run-in ring radius, as
measured from the axis of the expandable casing to the portion of
the second retainer ring, to a second set ring radius, as measured
from the axis of the expandable casing to the portion of the second
retainer ring, the second set ring radius being greater than the
second run-in ring radius, and the difference between the second
set ring radius and the second run-in ring radius defining a second
ring radius differential, and wherein the casing radius
differential is greater than the second ring radius differential.
Description
RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 60/933,183 filed Jun. 5, 2007.
BACKGROUND
[0002] The invention is directed to expandable casing packing
element systems for use in oil and gas wells and, in particular,
expandable casing packing element systems having extrudable sealing
elements for sealing open-hole wells.
[0003] Expandable casing having a sealing element such as a packer
have been used to seal the annulus of open-hole wells. In
operation, after the well is drilled into the earth formation, the
expandable casing is run into the well. The expandable casing has
disposed on it, or as part of the expandable casing string, a
sealing device such as a packer. The packer is designed to divide
the well by sealing against the well formation, thereby isolating a
lower portion of the well from an upper portion of the well.
[0004] After the expandable casing is run into the desired location
in the well, a cone or other device can be transported through the
bore of the expandable casing. As the cone, such as a swage,
travels downward, the expandable casing is expanded by the cone.
The expansion of the expandable casing causes the sealing device to
contact the formation and separate the open-hole well into at least
two isolated regions, one above the sealing device and one below
the sealing device.
[0005] The expandable casing and sealing devices disclosed herein
include components that, to the inventors' knowledge, are novel and
non-obvious from previous expandable casing and sealing
devices.
SUMMARY OF INVENTION
[0006] Broadly, the expandable casing packing element systems
disclosed herein include an expandable casing member having a
sealing device comprising a sealing element disposed between at
least two retainer rings. In one embodiment, both retainer rings
have flat cross-sections and the sealing element is forced radially
outward by the expansion of the expandable casing against the two
retainer rings such that the sealing element protrudes outwardly
beyond the retainer rings and engages the wall of the a wellbore in
three locations. The wellbore may be an opened-hole wellbore or a
cased wellbore. In another embodiment, both of the two retainer
rings include flares that extend outwardly from the body of the
expandable casing to which they are attached. As the expandable
casing is expanded, the flares are forced inward to compress the
sealing element which is then extruded radially outward through a
gap between the two retainer rings to engage and seal off the
wellbore.
[0007] Also disclosed is a method comprising the steps of: (a)
running an expandable casing string having a packing element system
attached thereto into a wellbore defined by an inner wall surface,
the packing element system having a sealing element and at least
two retainer rings, at one of the at least two retainer rings
overlapping the sealing element; (b) applying a radial load to
expand the expandable casing, causing the sealing element to be
extruded outwardly by at least one of the at least two retainer
rings applying an inward force to the sealing element; and (c)
continuing to apply the radial load causing the sealing element to
move radially outward into sealing engagement with the inner wall
surface of the wellbore. In one particular embodiment, the wellbore
is cased. In another specific embodiment, the wellbore is an
opened-hole wellbore.
BRIEF DESCRIPTION OF DRAWINGS
[0008] FIG. 1 is a cross-sectional view of one embodiment of an
expandable casing having a sealing device, FIG. 1 showing the
expandable casing as it is being expanded from its run-in position
to its expanded or set position.
[0009] FIG. 2 is a cross-sectional view of another specific
embodiment of an expandable casing having a sealing device, FIG. 2
showing the expandable casing in its run-in position.
[0010] FIG. 3 is a cross-sectional view of the expandable casing
shown in FIG. 2 shown in its expanded or set position.
[0011] While the invention will be described in connection with the
preferred embodiments, it will be understood that it is not
intended to limit the invention to that embodiment. On the
contrary, it is intended to cover all alternatives, modifications,
and equivalents, as may be included within the spirit and scope of
the invention as defined by the appended claims.
DETAILED DESCRIPTION OF INVENTION
[0012] Referring now to FIG. 1, in one specific embodiment,
expandable casing 30 is disposed within well 20 that has been
drilled into formation 26. Well 20 is defined by well inner wall
surface 22. Expandable casing 30 has upper end 32, lower end 34,
bore 36 defined by inner wall surface 38, outer wall surface 39,
and axis 40. Expandable casing 30 includes run-in diameter 42, set
diameter 44, and transitional diameter 46. Run-in diameter 42 is
less than set diameter 44 and transitional diameter 46 illustrates
the location of a cone (not shown) or other device used to expand
expandable casing 30 from the run-in diameter 42 to the set
diameter 44. Although a cone is described as being used to expand
expandable casing 30 from the run-in diameter 42 to the set
diameter 44, it is to be understood that any device or method known
to persons of ordinary skill in the art may be used to expand
expandable casing 30.
[0013] As illustrated in FIG. 1, disposed on outer wall surface 39
of expandable casing 30 are upper sealing device 50 and lower
sealing device 60. In this embodiment, upper sealing device 50 is
identical to lower sealing device 60 except that upper sealing
device 50 is shown in the set position and lower sealing device 60
is shown in the run-in position. It is to be understood, however,
that expandable casing 30 may have only one sealing device 50, 60,
or more than two sealing devices 50, 60. For convenience, both
upper and lower sealing devices 50, 60 will be discussed in greater
detail with reference to like numerals.
[0014] Sealing devices 50, 60 include annular deformable sealing
elements 51 having upper ends 52 and lower ends 54, upper retainer
ring 56, and lower retainer ring 58. Sealing element 51 is a
deformable element formed from an deformable material so that
radial outward movement of sealing element 51 away from axis 40 and
into upper and lower retainer rings 56, 58 causes sealing element
51 to extrude into sealing contact with inner wall surface 22 of
well 20. Suitable materials for forming sealing element 51 include,
but are not limited to, elastomers, rubbers, polymers, or
thermoplastics.
[0015] Additionally, sealing element 51 may have any shape desired
or necessary to provide the requisite compression, deformation, or
"extrusion" to form the seal with inner wall surface 22 of well 20.
As shown in FIG. 1, in this specific embodiment, sealing element 51
is formed in the shape of a sleeve having a thicker center portion
as compared to upper and lower ends 52, 54. This thicker portion is
disposed between upper and lower retainer rings 56, 58 and, as
shown with reference to sealing device 60, has an outer diameter
that is equal to the outer diameter of both upper and lower
retainer rings 56, 58 when in the run-in position. It is to be
understood, however, that sealing element 51 may have an outer
diameter that is less than the outer diameter of one or both of
upper or lower retainer rings 56, 58 when in its run-in position or
it may have an outer diameter that is greater than the outer
diameter of one or both upper or lower retainer rings 56, 58 when
in its run-in position.
[0016] Further, in the embodiment shown in FIG. 1, upper and lower
ends 52, 54 are shown protruding above and below upper and lower
retainer rings 56, 58; however, upper and lower ends 52, 54 are not
required to protrude above and below upper and lower retainer rings
in this manner.
[0017] Sealing element 51 is maintained against outer wall surface
39 of expandable casing 30 using any device or method known to
persons of ordinary skill in the art. For example, sealing element
51 may be chemically bonded to outer wall surface 39.
Alternatively, sealing element 51 can be maintained solely by upper
and lower retainer rings 56, 58.
[0018] Upper retainer rings 56 and lower retainer rings 58 are
expandable members disposed around the outer diameter of sealing
element 51 and, thus, can maintain or assist in maintaining sealing
element 51 along outer wall surface 39. In this embodiment both
upper retainer ring 56 and lower retainer ring 58 have a relatively
flat vertical cross-section parallel or substantially parallel to
the axial length of the expandable casing 30. As additionally shown
in FIG. 1, both upper and lower retainer rings 56, 58 have an axial
length greater than their width so that the inner diameter surface
area of both upper and lower retainer rings 56, 58 are in contact
with sealing element 51 to facilitate extrusion of sealing element
51 during expansion of expandable casing 30.
[0019] Although the shape of upper and lower retainer rings 56, 58
are discussed with reference to FIG. 1, it is to be understood that
upper and lower retainer rings 56, 58 may have any shape desired or
necessary to provide the necessary force against sealing element 51
during expansion of expandable casing 30 so that sealing element 51
is extruded to seal against inner wall surface 22 of well 20.
[0020] Further, upper and lower retainer rings 56, 58 may be formed
from any material known to persons of ordinary skill in the art.
For example, one or both of upper and lower retainer rings 56, 58
may be formed from stiffer elastomers, polymers, or metals such as
steel.
[0021] After expandable casing 30 is properly located within well
20, a cone (not shown) or other expanding device is run through
bore 36 of expandable casing 30. As the cone travels downward,
i.e., downhole, expandable casing 30 is forced radially outward
from axis 40. In so doing, run-in diameter 42 is radially expanded
to transition diameter 46 and ultimately to set diameter 44. As a
result of the radial expansion of expandable casing 30, sealing
element 51 is forced into upper and lower retainer rings 56, 58.
Although upper and lower retainer rings 56, 58 are radially
expandable, they are formed from a material that is stronger, i.e.,
more resistance to expansion, compared to the material used to form
sealing element 51. As a result, as expandable casing 30 is
expanded, sealing material 51 is compressed, deformed, or extruded
in between outer wall surface 39 of expandable casing and the inner
wall surfaces of upper and lower retainer rings 56, 58 defined by
the inner diameters of upper and lower retainer rings 56, 58. Due
to the compression of sealing element 51 between outer wall surface
39 of expandable casing 30 and the inner wall surfaces of upper and
lower retainer rings 56, 58, the center portion of sealing element
51 is extruded outwardly in between upper and lower retainer rings
56, 58; upper end 52 of sealing element 51 is extruded outwardly
above upper retainer ring 56; and lower end 54 of sealing element
51 is extruded outwardly below lower retainer ring 58 until all
three portions of sealing element 51 form a seal against inner wall
surface 22 of well 20. The distance between the outer diameter of
upper and lower retainer rings 56, 58 and inner wall surface 22 of
well 20 is referred to as the extrusion gap.
[0022] Referring now to FIGS. 2-3, in another embodiment,
expandable casing 130 has upper end 132, lower end 134, bore 136
defined by inner wall surface 138, outer wall surface 139, and axis
140. Expandable casing 30 includes run-in diameter defined by
run-in radius 142 (FIG. 2) and set diameter defined by set radius
144 (FIG. 3). Run-in radius 142 and, thus, the run-in diameter, is
less than set radius 144 and, thus, the set diameter. Expandable
casing 130 is radially expanded using a cone (not shown) or other
device used to expand expandable casing 130 from the run-in
diameter defined by run-in radius 142 to the set diameter defined
by set radius 144 in the same manner as the embodiment discussed
above with respect to FIG. 1.
[0023] As illustrated in FIG. 2, expandable casing 130 is in the
run-in position. Disposed on outer wall surface 139 of expandable
casing 130 is sealing device 150. Although only a single sealing
device 150 is shown, it is to be understood that more than one
sealing device may be disposed on outer wall surface 139 of
expandable casing 130.
[0024] Sealing device 150 includes annular sealing element 151,
upper retainer ring 156 and lower retainer ring 158. Annular
sealing element 151 is a deformable element formed from a
deformable material such as those discussed above with respect to
sealing element 51. In this embodiment, sealing element 151 has a
trapezoid section such that the inner surface of sealing element
151 has a longer axial length along outer wall surface 139 than the
axial length of the outer surface defined by the outer diameter of
sealing element 151.
[0025] Upper retainer ring 156 has upper flare portion 157 and
lower retainer ring 158 has lower flare portion 159 thereby forming
a cavity between upper retainer ring 156 and lower retainer ring
158 with a gap between the lowermost end of upper retainer ring 156
and the uppermost end of lower retainer ring 158. Sealing element
151 is disposed within the cavity. In one specific embodiment,
sealing element 151 is maintained along outer wall surface 139
through any device or method known to persons of ordinary skill in
the art, such as through chemical bonding or by upper and lower
retainer rings 156, 158.
[0026] As with the embodiment shown in FIG. 1, upper and lower
retainer rings 156, 158 may be formed from any material known to
persons of ordinary skill in the art. For example, one or both of
upper and lower retainer rings 156, 158 may be formed from stiffer
elastomers, polymers, or metals such as steel.
[0027] Upper flare portion 157 and lower flare portion 159 may have
any shape or angle relative to the remaining vertical portions of
upper and lower flare portions. For example, upper and lower flare
portions 157, 159 may be at an angle in a range greater than 0
degrees and less than 90 degrees relative to the vertical portions
of upper and lower flare portions 157, 159. Additionally, the angle
at which upper flare portion 157 intersects the remaining portion
of upper retainer ring may be different from the angle at which
lower flare portion 159 intersects the remaining portion of lower
retainer ring 158. In one specific embodiment, both of these angles
are within the range from 30 degrees to 60 degrees so that
sufficient inward force can be applied to sealing element 151
during expansion of expandable casing 130 to extrude sealing
element 151 through the gap between the lowermost and uppermost
ends of upper retainer ring 156 and lower retainer ring 158,
respectively. In the embodiment shown in FIGS. 2-3, upper and lower
flare portions 157, 159 are reciprocally shaped to receive sealing
element 151 so that a portion of both upper and lower flare
portions 157, 159 contact sealing element 151 during run-in.
[0028] Upper and lower retainer rings 156, 158 can be secured to
outer wall surface 139 through any device or method known to
persons of ordinary skill in the art. For example, upper and lower
retainer rings 156, 158 may be welded or epoxied to outer wall
surface 139. Alternatively, upper and lower retainer rings 156, 158
may be secured or formed integral with an expandable mandrel (not
shown) that is then secured such as through threads to an
expandable casing string.
[0029] As shown in FIG. 2, sealing element 151 of sealing device
150 is in its run-in position such that it does not protrude
outwardly from outer wall surface 139 past upper or lower retainer
rings 156, 158. It is to be understood that although sealing
element 151 is shown as having an outer diameter equal to the outer
diameters of upper and lower retainer rings 156, 158, sealing
element 151 may have either an outer diameter that is less than the
outer diameter of one or both of upper or lower retainer rings 156,
158 when in its run-in position, or an outer diameter that is
greater than the outer diameter of one or both of upper or lower
retainer rings 156, 158 when in its run-in position.
[0030] After expandable casing 130 is properly located within well
(not shown), a cone (not shown) or other expanding device is run
through bore 136 of expandable casing 130. As the cone travels
downward, i.e., downhole, expandable casing 130 is forced radially
outward from axis 140. In so doing, the run-in diameter illustrated
by run-in radius 142 is radially expanded to a transition diameter
(not shown) and ultimately to set diameter illustrated by set
radius 144 (FIG. 3). As a result of the radial expansion of
expandable casing 130, sealing element 151 is forced into upper and
lower flare portions 157, 159 of upper and lower retainer rings
156, 158. As with upper and lower retainer rings 56, 58, upper and
lower retainer rings 156, 158 are radially expandable; however,
they are formed from a material that is stronger, i.e., has more
resistance to expansion, compared to the material used to form
sealing element 151. As a result, as expandable casing 130 is
expanded, upper and lower flare portions 157, 159 bend inward
toward axis 140 as expandable casing 130 expands and, thus,
compress, deform, or extrude sealing element 151 within the cavity
in between outer wall surface 139 of expandable casing 130 and
upper and lower flare portions 157, 159. In other words, upper
flare portion 157 and lower flare portion 159 become more
straightened in line with the remaining portions of upper retainer
ring 156 and lower retainer ring 158, respectively, so that sealing
element 151 is forced radially outward.
[0031] Due to the compression of sealing element 151 between outer
wall surface 139 of expandable casing 130 and the upper and lower
flare portions 157, 159, sealing element 151 is extruded outwardly
from the cavity through the gap located between the lowermost end
of upper retainer ring 156 and the upper most end of lower retainer
ring 158 until sealing element 151 forms a seal against the inner
wall surface of the well. This distance between the outermost
diameters of upper and lower retainer rings 156, 158 and the inner
wall surface of the well is referred to as the extrusion gap.
[0032] It is to be understood that the invention is not limited to
the exact details of construction, operation, exact materials, or
embodiments shown and described, as modifications and equivalents
will be apparent to one skilled in the art. For example, the
sealing devices may be disposed on an expandable mandrel that is
placed within an expandable casing string. Additionally, the
expandable casing may have one or more sealing devices 50 or 60
together with one or more sealing devices 150. Moreover, a spacer
may be disposed in between outer wall surface 39 of expandable
casing 30 and the inner diameter of sealing element 151 to assist
in extrusion of sealing element 151 during expansion of expandable
casing 130. Further, the inner diameter of upper retainer ring 56
is not required to be equal to the inner diameter of lower retainer
ring 58. Likewise, the shape of upper flare portion 157 is not
required to be the same shape as lower flare portion 159.
Additionally, the expandable casing 30, 130 may be disposed in a
cased wellbore as opposed to an open-hole wellbore. Thus, the term
"wellbore" as used herein includes a cased wellbore as well as an
opened-hole wellbore. Accordingly, the invention is therefore to be
limited only by the scope of the appended claims.
* * * * *