U.S. patent application number 14/520189 was filed with the patent office on 2016-04-21 for apparatus for zonal communication interruption.
The applicant listed for this patent is Jose Oliverio Alvarez, David A. Stiles. Invention is credited to Jose Oliverio Alvarez, David A. Stiles.
Application Number | 20160108698 14/520189 |
Document ID | / |
Family ID | 55748630 |
Filed Date | 2016-04-21 |
United States Patent
Application |
20160108698 |
Kind Code |
A1 |
Alvarez; Jose Oliverio ; et
al. |
April 21, 2016 |
Apparatus for Zonal Communication Interruption
Abstract
A method for providing zonal communication interruption in a
wellbore, comprising: positioning a plurality of cement diverters
axially along an outer surface of a tubular member, each cement
diverter having an axial length and an azimuthal extension of less
than 360.degree., wherein the azimuthal position of at least one
cement diverter is axially rotated from an adjacent cement
diverter; positioning the tubular member within the wellbore; and
flowing cement into an annulus formed between an inner surface of
the wellbore and the outer surface of the tubular member, wherein
the positioning of the plurality of cement diverters provides zonal
communication interruption about every 10 to 20 feet (about every
3.0 to about 6.1 meters) axially along the tubular member. An
apparatus for providing zonal communication interruption in a
wellbore is also provided.
Inventors: |
Alvarez; Jose Oliverio;
(Houston, TX) ; Stiles; David A.; (Spring,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Alvarez; Jose Oliverio
Stiles; David A. |
Houston
Spring |
TX
TX |
US
US |
|
|
Family ID: |
55748630 |
Appl. No.: |
14/520189 |
Filed: |
October 21, 2014 |
Current U.S.
Class: |
166/285 ;
166/191 |
Current CPC
Class: |
E21B 33/14 20130101 |
International
Class: |
E21B 33/138 20060101
E21B033/138; E21B 43/14 20060101 E21B043/14; E21B 33/124 20060101
E21B033/124 |
Claims
1. A method for providing zonal communication interruption in a
wellbore, comprising: (a) positioning a plurality of cement
diverters axially along an outer surface of a tubular member, each
cement diverter having an axial length and an azimuthal extension
of less than 360.degree., wherein the azimuthal position of at
least one cement diverter is axially rotated from an adjacent
cement diverter; (b) positioning the tubular member within the
wellbore; and (c) flowing cement into an annulus formed between an
inner surface of the wellbore and the outer surface of the tubular
member, wherein the positioning of the plurality of cement
diverters provides zonal communication interruption about every 10
to 20 feet (about every 3.0 to about 6.1 meters) axially along the
tubular member.
2. The method of claim 1, wherein a first cement diverter of the
plurality of cement diverters is positioned at a first distance
from a first end of the tubular member.
3. The method of claim 2, wherein a second cement diverter of the
plurality of cement diverters is positioned at a second distance
from a first end of the tubular member, the second distance greater
than the first distance, the azimuthal position of the second
cement diverter rotated by at least about 30.degree. from the first
cement diverter.
4. The method of claim 3, wherein a third cement diverter of the
plurality of cement diverters is positioned at a third distance
from a first end of the tubular member, the third distance greater
than the second distance, the azimuthal position of the third
cement diverter rotated by at least about 30.degree. from the
second diverter segment.
5. The method of claim 4, wherein a fourth cement diverter of the
plurality of cement diverters is positioned at a fourth distance
from a first end of the tubular member, the fourth distance greater
than the third distance, the azimuthal position of the fourth
cement diverter rotated by at least about 30.degree. from the third
cement diverter.
6. The method of claim 1, wherein the azimuthal position of each
cement diverter is rotated between about 30.degree. and about
270.degree. from an adjacent cement diverter.
7. The method of claim 6, wherein the azimuthal position of each
cement diverter is rotated between about 90.degree. and about
180.degree. from an adjacent cement diverter.
8. The method of claim 1, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 35.degree.
and about 270.degree..
9. The method of claim 8, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 90.degree.
and about 180.degree..
10. The method of claim 1, wherein each of the plurality of cement
diverters is between about two and about ten feet (about every 3.0
to about 6.1 meters) in length.
11. The method of claim 1, wherein each of the plurality of cement
diverters is axially spaced apart along the tubular member by about
3 to about 20 feet (about 0.9 to about 6.1 meters).
12. The method of claim 1, wherein each of the plurality of cement
diverters is swellable.
13. The method of claim 12, wherein each of the plurality of cement
diverters has a swellable coating applied thereto.
14. The method of claim 12, wherein each of the plurality of cement
diverters is inflatable.
15. The method of claim 1, wherein the wellbore comprises an
inclined and/or horizontal section.
16. An apparatus for providing zonal communication interruption in
a wellbore, comprising: a tubular member having a plurality of
cement diverters positioned axially along an outer surface of a
tubular member, each cement diverter having an axial length and an
azimuthal extension of less than 360.degree., wherein the azimuthal
position of at least one cement diverter is axially rotated from an
adjacent cement diverter and the positioning of the plurality of
cement diverters is effective to provide zonal communication
interruption about every 10 to 20 feet (about every 3.0 to about
6.1 meters) axially along the tubular member.
17. The apparatus of claim 16, wherein a first cement diverter of
the plurality of cement diverters is positioned at a first distance
from a first end of the tubular member.
18. The apparatus of claim 17, wherein a second cement diverter of
the plurality of cement diverters is positioned at a second
distance from a first end of the tubular member, the second
distance greater than the first distance, the azimuthal position of
the second cement diverter rotated by at least about 30.degree.
from the first cement diverter.
19. The apparatus of claim 18, wherein a third cement diverter of
the plurality of cement diverters is positioned at a third distance
from a first end of the tubular member, the third distance greater
than the second distance, the azimuthal position of the third
cement diverter rotated by at least about 30.degree. from the
second diverter segment.
20. The apparatus of claim 19, wherein a fourth cement diverter of
the plurality of cement diverters is positioned at a fourth
distance from a first end of the tubular member, the fourth
distance greater than the third distance, the azimuthal position of
the fourth cement diverter rotated by at least about 30.degree.
from the third cement diverter.
21. The apparatus of claim 16, wherein the azimuthal position of
each cement diverter is rotated between about 30.degree. and about
270.degree. from an adjacent cement diverter.
22. The apparatus of claim 21, wherein the azimuthal position of
each cement diverter is rotated between about 90.degree. and about
180.degree. from an adjacent cement diverter.
23. The apparatus of claim 16, wherein each of the plurality of
cement diverters has an azimuthal extension of between about
35.degree. and about 270.degree..
24. The apparatus of claim 23, wherein each of the plurality of
cement diverters has an azimuthal extension of between about
90.degree. and about 180.degree..
25. The apparatus of claim 16, wherein each of the plurality of
cement diverters is between about two and about ten feet (about
every 3.0 to about 6.1 meters) in length.
26. The apparatus of claim 16, wherein each of the plurality of
cement diverters is axially spaced apart along the tubular member
by about 3 to about 20 feet (about 0.9 to about 6.1 meters).
27. The apparatus of claim 16, wherein each of the plurality of
cement diverters is swellable.
28. The apparatus of claim 27, wherein each of the plurality of
cement diverters has a swellable coating applied thereto.
29. The apparatus of claim 27, wherein each of the plurality of
cement diverters is inflatable.
30. The apparatus of claim 16, wherein the wellbore comprises an
inclined and/or horizontal section.
31. A method of creating a wellbore in an underground formation,
comprising the steps of: (a) drilling a borehole in the underground
formation; (b) installing a tubular member into the borehole, the
tubular member having a plurality of cement diverters positioned
axially along an outer surface of the tubular member, each cement
diverter having an axial length and an azimuthal extension of less
than 360.degree., wherein the azimuthal position of at least one
cement diverter is axially rotated from an adjacent cement
diverter; and (c) flowing cement into an annulus formed between an
inner surface of the wellbore and the outer surface of the tubular
member, wherein the positioning of the plurality of cement
diverters provides zonal communication interruption about every 10
to 20 feet (about every 3.0 to about 6.1 meters) axially along the
tubular member.
32. The method of claim 31, wherein the azimuthal position of each
cement diverter is rotated between about 30.degree. and about
270.degree. from an adjacent cement diverter.
33. The method of claim 32, wherein the azimuthal position of each
cement diverter is rotated between about 90.degree. and about
180.degree. from an adjacent cement diverter.
34. The method of claim 31, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 35.degree.
and about 270.degree..
35. The method of claim 34, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 90.degree.
and about 180.degree..
36. The method of claim 31, wherein each of the plurality of cement
diverters is between about two and about ten feet (about every 3.0
to about 6.1 meters) in length.
37. The method of claim 31, wherein each of the plurality of cement
diverters is axially spaced apart along the tubular member by about
3 to about 20 feet (about 0.9 to about 6.1 meters).
38. The method of claim 31, wherein each of the plurality of cement
diverters is swellable.
39. The method of claim 38, wherein each of the plurality of cement
diverters has a swellable coating applied thereto.
40. The method of claim 39, wherein each of the plurality of cement
diverters is inflatable.
41. A method of producing hydrocarbons from a production well of an
underground formation, comprising the steps of: (a) installing a
tubular member into a wellbore of an underground formation, the
tubular member having a plurality of cement diverters positioned
axially along an outer surface of the tubular member, each cement
diverter having an axial length and an azimuthal extension of less
than 360.degree., wherein the azimuthal position of at least one
cement diverter is axially rotated from an adjacent cement
diverter; (b) flowing cement into an annulus formed between an
inner surface of the wellbore and the outer surface of the tubular
member to form a production well; and (c) producing fluids
containing hydrocarbons from the production well wherein the
positioning of the plurality of cement diverters provides zonal
communication interruption about every 10 to 20 feet axially (about
every 3.0 to about 6.1 meters) along the tubular member.
42. The method of claim 41, wherein the azimuthal position of each
cement diverter is rotated between about 30.degree. and about
270.degree. from an adjacent cement diverter.
43. The method of claim 42, wherein the azimuthal position of each
cement diverter is rotated between about 90.degree. and about
180.degree. from an adjacent cement diverter.
44. The method of claim 41, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 35.degree.
and about 270.degree..
45. The method of claim 44, wherein each of the plurality of cement
diverters has an azimuthal extension of between about 90.degree.
and about 180.degree..
46. The method of claim 41, wherein each of the plurality of cement
diverters is between about two and about ten feet (about every 3.0
to about 6.1 meters) in length.
47. The method of claim 41, wherein each of the plurality of cement
diverters is axially spaced apart along the tubular member by about
3 to about 20 feet (about 0.9 to about 6.1 meters).
48. The method of claim 41, wherein each of the plurality of cement
diverters is swellable.
49. The method of claim 48, wherein each of the plurality of cement
diverters has a swellable coating applied thereto.
50. The method of claim 41, wherein the wellbore comprises an
inclined and/or horizontal section.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional No.
61/914,735, filed Dec. 11, 2013, which is incorporated herein in
its entirety for all purposes.
FIELD
[0002] The present disclosure broadly relates to well cementing and
completions. More particularly, the present disclosure relates to
an apparatus and method for providing zonal communication
interruption.
BACKGROUND
[0003] After a section of a well is drilled, a metal casing is
lowered and cement is pumped inside the casing. The cement then
travels through the annulus between the formation rock and the
external face of the casing and allowed to set in the annulus.
Cementing accomplishes the following purposes: zonal isolation,
pressure isolation, casing corrosion protection, casing support and
drilling fluid recovery.
[0004] However, in many situations the cement does not perform as
expected. This can cause the well to lose integrity, producing
zonal communication that can have catastrophic results.
Communication between zones is usually through micro channels in
the cement. Examples of these situations include: cement slurry not
placed properly within the annulus due to poor centralization, poor
hole quality, inefficient mud removal, etc.; cement slurry
contamination with formation fluids; and long term failure due to
changes in pressure and/or temperature.
[0005] Current solutions to prevent micro channels include the use
of centralizers, including bow springs, rigid centralizers and
solid centralizers. Centralizer efficiency is dependent upon hole
quality; so in the case of washouts, centralizer efficiency is
greatly reduced. Another solution presently employed is the use of
swellable packers: These are elastomeric rings placed within the
annulus that swell to fill the gap space between casing and
formation. However, like most current technologies, swellable
packers can only address the micro channels between pipe and cement
and not between cement and formation. Another current solution is
the use of compressible cements, thixotropic cements, surfactant
cements, etc.
[0006] Despite these solutions, there exists a need to address
problems associated with imperfect zonal isolation. Therefore, what
is needed is an improved method and apparatus for providing zonal
communication interruption in a wellbore.
SUMMARY
[0007] In one aspect, disclosed is a method for providing zonal
communication interruption in a wellbore. The method includes the
steps of positioning a plurality of cement diverters axially along
an outer surface of a tubular member, each cement diverter having
an axial length and an azimuthal extension of less than
360.degree., wherein the azimuthal position of at least one cement
diverter is axially rotated from an adjacent cement diverter;
positioning the tubular member within the wellbore; and flowing
cement into an annulus formed between an inner surface of the
wellbore and the outer surface of the tubular member, wherein the
positioning of the plurality of cement diverters provides zonal
communication interruption about every 10 to 20 feet (about every
3.0 to about 6.1 meters) axially along the tubular member.
[0008] In some forms, a first cement diverter of the plurality of
cement diverters is positioned at a first distance from a first end
of the tubular member. In some forms, a second cement diverter of
the plurality of cement diverters is positioned at a second
distance from a first end of the tubular member, the second
distance greater than the first distance, the azimuthal position of
the second cement diverter rotated by at least about 30.degree.
from the first cement diverter.
[0009] In some forms, a third cement diverter of the plurality of
cement diverters is positioned at a third distance from a first end
of the tubular member, the third distance greater than the second
distance, the azimuthal position of the third cement diverter
rotated by at least about 30.degree. from the second diverter
segment. In some forms, a fourth cement diverter of the plurality
of cement diverters is positioned at a fourth distance from a first
end of the tubular member, the fourth distance greater than the
third distance, the azimuthal position of the fourth cement
diverter rotated by at least about 30.degree. from the third cement
diverter.
[0010] In some forms, the azimuthal position of each cement
diverter is rotated between about 30.degree. and about 270.degree.
from an adjacent cement diverter. In some forms, the azimuthal
position of each cement diverter is rotated between about
90.degree. and about 180.degree. from an adjacent cement
diverter.
[0011] In some forms, each of the plurality of cement diverters has
an azimuthal extension of between about 35.degree. and about
270.degree.. In some forms, each of the plurality of cement
diverters has an azimuthal extension of between about 90.degree.
and about 180.degree..
[0012] In some forms, each of the plurality of cement diverters is
between about two and about ten feet (about every 0.6 to about 3.0
meters) in length.
[0013] In some forms, each of the plurality of cement diverters is
axially spaced apart along the tubular member by about 3 to about
20 feet.
[0014] In some forms, each of the plurality of cement diverters is
swellable. In some forms, each of the plurality of cement diverters
has a swellable coating applied thereto.
[0015] In some forms, of the plurality of cement diverters is
inflatable.
[0016] In some forms, the wellbore comprises an inclined and/or
horizontal section.
[0017] In another aspect, disclosed is an apparatus for providing
zonal communication interruption in a wellbore. The apparatus
includes a tubular member having a plurality of cement diverters
positioned axially along an outer surface of a tubular member, each
cement diverter having an axial length and an azimuthal extension
of less than 360.degree., wherein the azimuthal position of at
least one cement diverter is axially rotated from an adjacent
cement diverter and the positioning of the plurality of cement
diverters is effective to provide zonal communication interruption
about every 10 to 20 feet (about every 3.0 to about 6.1 meters)
axially along the tubular member.
[0018] In some forms, a first cement diverter of the plurality of
cement diverters is positioned at a first distance from a first end
of the tubular member. In some forms, a second cement diverter of
the plurality of cement diverters is positioned at a second
distance from a first end of the tubular member, the second
distance greater than the first distance, the azimuthal position of
the second cement diverter rotated by at least about 30.degree.
from the first cement diverter.
[0019] In some forms, a third cement diverter of the plurality of
cement diverters is positioned at a third distance from a first end
of the tubular member, the third distance greater than the second
distance, the azimuthal position of the third cement diverter
rotated by at least about 30.degree. from the second diverter
segment. In some forms, a fourth cement diverter of the plurality
of cement diverters is positioned at a fourth distance from a first
end of the tubular member, the fourth distance greater than the
third distance, the azimuthal position of the fourth cement
diverter rotated by at least about 30.degree. from the third cement
diverter.
[0020] In some forms, the azimuthal position of each cement
diverter is rotated between about 30.degree. and about 270.degree.
from an adjacent cement diverter. In some forms, the azimuthal
position of each cement diverter is rotated between about
90.degree. and about 180.degree. from an adjacent cement
diverter.
[0021] In some forms, each of the plurality of cement diverters has
an azimuthal extension of between about 35.degree. and about
270.degree.. In some forms, each of the plurality of cement
diverters has an azimuthal extension of between about 90.degree.
and about 180.degree..
[0022] In some forms, each of the plurality of cement diverters is
between about two and about ten feet (about every 3.0 to about 6.1
meters) in length.
[0023] In some forms, each of the plurality of cement diverters is
axially spaced apart along the tubular member by about 3 to about
20 feet (about 0.9 to about 6.1 meters).
[0024] In some forms, each of the plurality of cement diverters is
swellable. In some forms, each of the plurality of cement diverters
has a swellable coating applied thereto.
[0025] In some forms, the plurality of cement diverters are part of
the completion, forming protuberances radially extending from the
outer surface of the tubular member or casing.
[0026] In some forms, the plurality of cement diverters is
inflatable.
[0027] In some forms, the wellbore comprises an inclined and/or
horizontal section.
[0028] In another aspect, disclosed is a method of creating a
wellbore in an underground formation. The method includes the steps
of drilling a borehole in the underground formation; installing a
tubular member into the borehole, the tubular member having a
plurality of cement diverters positioned axially along an outer
surface of the tubular member, each cement diverter having an axial
length and an azimuthal extension of less than 360.degree., wherein
the azimuthal position of at least one cement diverter is axially
rotated from an adjacent cement diverter; and flowing cement into
an annulus formed between an inner surface of the wellbore and the
outer surface of the tubular member, wherein the positioning of the
plurality of cement diverters provides zonal communication
interruption about every 10 to 20 feet (about every 3.0 to about
6.1 meters) axially along the tubular member.
[0029] In yet another aspect, disclosed is a method of producing
hydrocarbons from a production well of an underground formation.
The method includes the steps of installing a tubular member into a
wellbore of an underground formation, the tubular member having a
plurality of cement diverters positioned axially along an outer
surface of the tubular member, each cement diverter having an axial
length and an azimuthal extension of less than 360.degree., wherein
the azimuthal position of at least one cement diverter is axially
rotated from an adjacent cement diverter; flowing cement into an
annulus formed between an inner surface of the wellbore and the
outer surface of the tubular member to form a production well; and
producing fluids containing hydrocarbons from the production well,
wherein the positioning of the plurality of cement diverters
provides zonal communication interruption about every 10 to 20 feet
(about every 3.0 to about 6.1 meters) axially along the tubular
member.
[0030] In one form, each cement diverter may be a 180 degree
extension of a solid with a swellable elastomer on its outer
surface. The length of each cement diverter is between about two
and ten feet (about every 3.0 to about 6.1 meters). In one form,
the cement diverters may be positioned about 3 to about 20 feet
(about 0.9 to about 6.1 meters) apart along the tubular member. In
one form, a first cement diverter is rotated 180.degree. from a
second cement diverter. In one form a third cement diverter may be
rotated 90.degree. with respect to the second cement diverter and
then the pattern is repeated. The result of this arrangement is to
force slurry into small gaps, which in turn assures that there will
be channel interruption every 10 to 20 feet (about every 3.0 to
about 6.1 meters) in the worst case eccentricity scenario.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 presents a schematic plan view of an illustrative,
non-exclusive example of an apparatus for providing zonal
communication interruption in a wellbore, according to the present
disclosure.
[0032] FIG. 2 presents a schematic end view of the illustrative,
non-exclusive example of an apparatus for providing zonal
communication interruption in a wellbore of FIG. 1, according to
the present disclosure.
[0033] FIG. 3 presents a cross-sectional view of a tubular forming
an eccentric annulus within a borehole and its impact on cement
placement and the creation of non-cement containing channels.
[0034] FIG. 4 presents a schematic cross-sectional view of an
apparatus for providing zonal communication interruption in a
wellbore, according to the present disclosure, and its effect on
cement placement.
[0035] FIG. 5 presents another schematic cross-sectional view of an
apparatus for providing zonal communication interruption in a
wellbore, according to the present disclosure, and its effect on
cement placement.
DETAILED DESCRIPTION
[0036] FIGS. 1, 2, 4 and 5 provide illustrative, non-exclusive
examples of an apparatus for providing zonal communication
interruption in a wellbore, according to the present disclosure,
together with systems, and/or assemblies that may include, be
associated with, be operatively attached to, and/or utilize such an
apparatus for providing zonal communication interruption in a
wellbore. In FIGS. 1-5, like numerals denote like, or similar,
structures and/or features; and each of the illustrated structures
and/or features may not be discussed in detail herein with
reference to the figures. Similarly, each structure and/or feature
may not be explicitly labeled in the figures; and any structure
and/or feature that is discussed herein with reference to the
figures may be utilized with any other structure and/or feature
without departing from the scope of the present disclosure.
[0037] In general, structures and/or features that are, or are
likely to be, included in a given embodiment are indicated in solid
lines in the figures, while optional structures and/or features are
indicated in broken lines. However, a given embodiment is not
required to include all structures and/or features that are
illustrated in solid lines therein, and any suitable number of such
structures and/or features may be omitted from a given embodiment
without departing from the scope of the present disclosure.
[0038] By use of the term "vertical," "vertically" or "vertical
section," when referring to a well, a wellbore, tubing or tubular
member, or section or portion thereof, is meant that such well,
wellbore, tubing or tubular member, or section thereof, is
positioned or is to be positioned, so as to be substantially normal
to a plane formed at the ground or surface level of the well or
wellbore.
[0039] By use of the term "inclined" or "inclined section," when
referring to a well, a wellbore, tubing or tubular member, or
section or portion thereof, is meant that such well, wellbore,
tubing or tubular member, or section thereof, is positioned, or is
to be positioned, so as to deviate in direction from vertical and
encompasses a well, a wellbore, tubing or tubular member, or
section or portion thereof, extending in horizontally or in a
horizontal direction.
[0040] By use of the term "horizontal," "horizontally" or
"horizontal section," when referring to a well, a wellbore, tubing
or tubular member, or section or portion thereof, is meant that
such well, wellbore, tubing or tubular member, or section thereof,
is positioned or is to be positioned, so as to travel along a plane
substantially parallel to a plane formed tangentially at the ground
or surface level of the well or wellbore.
[0041] By use of the term "zonal communication interruption," when
referring to a well, a wellbore, tubing or tubular member, or
section or portion thereof, is meant that communication between one
or more zones of a well, usually through micro-channels in a cement
sheath, placed between a wellbore and a tubular member, is at least
partially blocked or impeded with respect to flow. Such
communication between one or more zones of a well may be due to the
presence in the cement sheath of channels, micro-channels, annuli,
or the like.
[0042] Referring now to FIG. 1, a schematic plan view of an
illustrative, non-exclusive example of an apparatus 10 for
providing zonal communication interruption in a wellbore, according
to the present disclosure, is presented. Apparatus 10 includes a
tubular member 12 having a first end 14 and a second end 16. As
shown, tubular member 12 includes a plurality of cement diverters
18 positioned axially along an outer surface 20 of tubular member
12, each cement diverter 18 having an axial length L and an
azimuthal extension E of less than 360.degree.. Referring to FIGS.
1 and 2, it may be seen that the azimuthal position P.sub.1 of at
least one cement diverter is axially rotated by an angle .theta.
from an adjacent cement diverter having an azimuthal position
P.sub.2.
[0043] Still referring to FIG. 1, in some forms, a first cement
diverter 18' of the plurality of cement diverters 18 is positioned
at a first distance d.sub.1 from the first end 14 of tubular member
12. Likewise, in some forms, a second cement diverter 18'' of the
plurality of cement diverters 18 may be positioned at a second
distance d.sub.2 from first end 14 of tubular member 12. As shown
in FIG. 1, second distance d.sub.2 is greater than first distance
d.sub.1. Also, as shown in FIG. 2, the azimuthal position P.sub.2
of the second cement diverter 18'' is rotated by at least about
30.degree. from the first cement diverter 18'.
[0044] In some forms, a third cement diverter 18''' of the
plurality of cement diverters 18 is positioned at a third distance
d.sub.3 from the first end 14 of tubular member 12, the third
distance d.sub.3 greater than the second distance d.sub.2. Also, as
shown in FIG. 2, the azimuthal position P.sub.3 of the third cement
diverter 18''' is rotated by at least about 30.degree. from the
second diverter segment 18''.
[0045] In some forms, a fourth cement diverter 18'''' of the
plurality of cement diverters 18 is positioned at a fourth distance
d.sub.4 from first end 14 of the tubular member 12, the fourth
distance d.sub.4 greater than the third distance d.sub.3. Also, as
shown in FIG. 2, the azimuthal position P.sub.4 of the fourth
cement diverter 18'''' is rotated by at least about 30.degree. from
the third cement diverter 18'''.
[0046] Still referring to FIG. 2, in one form, the azimuthal
position of each cement diverter 18 is rotated between about
30.degree. and about 270.degree. from an adjacent cement diverter
18. In some forms, the azimuthal position of each cement diverter
18 is rotated between about 90.degree. and about 180.degree. from
an adjacent cement diverter 18.
[0047] In some forms, each of the plurality of cement diverters 18
has an azimuthal extension E of between about 35.degree. and about
270.degree.. In some forms, each of the plurality of cement
diverters 18 has an azimuthal extension E of between about
90.degree. and about 180.degree..
[0048] In some forms, each of the plurality of cement diverters 18
has a length L between about two and about ten feet (about every
3.0 to about 6.1 meters) in length. In some forms, each of the
plurality of cement diverters 18 has an axial spacing S along the
tubular member of between about 3 to about 20 feet (about 0.9 to
about 6.1 meters).
[0049] To enhance the performance of cement diverters 18, one or
more of the plurality of cement diverters may be swellable. In some
forms, one or more of the plurality of cement diverters 18 has a
swellable coating applied thereto. In some forms, one or more of
the plurality of cement diverters 18 may be of an inflatable
design.
[0050] As is well known to those skilled in the art, swellable
materials have the characteristic of being able to move from a
retracted position to an expanded position when exposed to the
action of a triggering agent. The triggering agent may be a fluid
absorbed by the material that consequently swells. In its expanded
position, the volume of the swellable material is greater than in
its non-swollen position, which makes it able to fill adjacent
spaces unoccupied prior to swelling and therefore seals fluid
channels in its vicinity. Swellable materials can be deployed
downhole in their retracted position prior to swelling and
activated downhole.
[0051] Suitable water-swellable materials include acrylic acid type
polymers, carboxymethyl cellulose type polymers, highly swelling
clay minerals, isobutylene maleic anhydride, polyethylene oxide
polymers, polyvinyl alcohol cyclic acid anhydride graft copolymer,
sodium bentonite (montmorillonite), starch polyacrylate acid graft
copolymer, starch polyacrylonitrile graft copolymers, vinyl
acetate-acrylate copolymers, and combination thereof. More
generally, they can also include super absorbent polymers (SAPs) or
hydrogels.
[0052] Suitable hydrocarbon-swellable materials include natural
rubber, polyisoprene rubber, vinyl acetate rubber, polychloroprene
rubber, acrylonitrile butadiene rubber, hydrogenated acrylonitrile
butadiene rubber, ethylene propylene diene monomer, ethylene
propylene monomer rubber, polynorbornen, styrene butadiene rubber,
styrene/propylene/diene monomer, brominated
poly(isobutylene-co-4-methylstyrene) (BIMS), butyl rubber,
chlorosulphonated polyethylenes, polyacrylate rubber, polyurethane,
silicone rubber, brominated butyl rubber, chlorinated butyl rubber,
chlorinated polyethylene, epichlorohydrin ethylene oxide copolymer,
ethylene acrylate rubber, ethylene propylene diene terpolymer
rubber, sulphonated polyethylene, fluoro silicone rubbers,
fluoroelastomer, substituted styrene acrylate copolymer and
combination thereof.
[0053] The operation of the apparatus 10 for providing zonal
communication interruption in a wellbore, according to the present
disclosure, will be described by reference to FIGS. 3-6. The
purpose of the cement placed between the casing or tubular member
and the wellbore wall in a hydrocarbon well is to provide
mechanical support to the casing or tubular member and to ensure
good annular zonal isolation. However, due to poor cement placement
and to stresses applied by both the casing and the formation, the
cement may fail in ensuring well integrity.
[0054] Examples of zonal isolation problems will now be described.
Referring to FIG. 3, a subterranean formation 100 has a borehole
102 formed therein. As may be appreciated, the borehole may
comprise a vertical section and/or an inclined and/or horizontal
section. A casing or tubular member 104 is placed to consolidate
the formation. When the casing 104 is not centralized in the
borehole 102, as shown in FIG. 3, the eccentricity can be such that
the cement 106 is not placed properly in an annulus 108 between the
casing 104 and the borehole wall 110. As a result, the annulus 108
between the casing 104 and the formation 100 is only partly filled
with the cement 106, leaving a portion 112 of the annulus 108 not
filled with cement. During placement the cement slurry will mainly
go through the larger gaps, leaving channels in the small gap
region.
[0055] In a horizontal well example, a channel may form on top of
the casing, where water separates (called free water). As such,
micro-channels can appear either between the casing 112 and the
cement 106 or between the formation 100 and the cement 106. For
example, bad drilling mud removal may occur while pumping the
cement slurry in the annulus 108, thereby leaving mud films either
between the casing 104 and the cement 106 or between the cement 106
and the formation 100. This results in fluid channeling and loss of
zonal isolation. Both types of micro-channels may also appear
during the life of the cement due to the phenomenon of cement
debonding.
[0056] An even more complex zonal isolation problem results from
cracks in the cement. Cracks develop due to cement ageing,
seismologic activity in the formation or vibrations of the casing
or pressure/temperature variation.
[0057] Referring now to FIG. 4, a schematic view of an apparatus
200 for providing zonal communication interruption in a wellbore
102 and its effect on cement placement will be described. In this
case, again it will be difficult to center the casing in the
wellbore 102, which will lead to a high degree of eccentricity. To
address this issue, apparatus 200 is placed within the wellbore
102. Apparatus 200 includes a tubular member 212 and a plurality of
cement diverters 218 positioned axially along an outer surface 220
of tubular member 212, each cement diverter 218 having an axial
length L and an azimuthal extension E of less than 360.degree..
[0058] As shown in FIGS. 4 and 5, each cement diverter 218 may have
an azimuthal extension E of approximately less than 180.degree.
extension of a solid. A swellable elastomer may be applied to the
surface of each cement diverter 218. The length L of each cement
diverter 218 may be about 2 to 10 feet (about every 3.0 to about
6.1 meters). A spacing S between each cement diverter 218 may be
about 3 to 20 feet (about 0.9 to about 6.1 meters), along the pipe
and then another cement diverter 218 positioned, but, as shown in
FIG. 5, the next cement diverter 218 is rotated 180.degree..
[0059] In some forms, after another axial spacing of about 3 to 20
feet (about 0.9 to about 6.1 meters), another cement diverter 418
is positioned, this time, by way of example, but not of limitation,
rotated 180.degree. with respect to the previous cement diverter
418, then the next one rotated 90.degree.. As may be appreciated by
one of skill in the art, the pattern may be repeated. The apparatus
for providing zonal communication interruption in a wellbore then
forces slurry into the small gaps, which in turn assures that there
will be zonal communication interruption about every 10 to 20 feet
(about every 3.0 to about 6.1 meters), in the worst case
eccentricity/borehole quality scenario.
[0060] By seeking to address the worst case eccentricity/borehole
quality scenario, the apparatus for providing zonal communication
interruption in a wellbore may be said to be designed using minimax
principles for these adverse scenarios. Minimax, sometimes referred
to as minmax, is a decision rule used in decision theory, game
theory, statistics and philosophy for minimizing the possible loss
of a worst case, maximum loss, scenario. Originally formulated for
two-player, zero-sum game theory, covering both the cases where
players take alternate moves and those where they make simultaneous
moves, it has also been extended to more complex games and to
general decision making in the presence of uncertainty.
[0061] Minimax theory has been extended to decisions where there is
no other player, but where the consequences of decisions depend on
unknown facts. For example, deciding to prospect for minerals
entails a cost that will be wasted if the minerals are not present,
but will bring major rewards if they are discovered. One approach
is to treat this as a game against nature, and using a similar
mindset as Murphy's law, take an approach which minimizes the
maximum expected loss, using the same techniques as in the
two-person zero-sum games.
[0062] A key feature of minimax decision making is being
non-probabilistic: in contrast to decisions using expected value or
expected utility, it makes no assumptions about the probabilities
of various outcomes, just scenario analysis of what the possible
outcomes are. It is thus robust to changes in the assumptions, as
these other decision techniques are not.
[0063] Further, minimax only requires ordinal measurement (that
outcomes be compared and ranked), not interval measurements (that
outcomes include "how much better or worse"), and returns ordinal
data, using only the modeled outcomes: the conclusion of a minimax
analysis is: "this strategy is minimax, as the worst case is
(outcome), which is less bad than any other strategy." Compare to
expected value analysis, whose conclusion is of the form: "this
strategy yields E(X)=n." Minimax thus can be used on ordinal data,
and can be more transparent. Modeling a downhole completion case
where micro-channels will be present due to casing eccentricity or
poor borehole quality, and the various completion design approaches
to deal with such issues, may be thought of in this manner.
[0064] As such, disclosed herein is a method for providing zonal
communication interruption in a wellbore, comprising: positioning a
plurality of cement diverters axially along an outer surface of a
tubular member, each cement diverter having an axial length and an
azimuthal extension of less than 360.degree., wherein the azimuthal
position of at least one cement diverter is axially rotated from an
adjacent cement diverter; positioning the tubular member within the
wellbore; and flowing cement into an annulus formed between an
inner surface of the wellbore and the outer surface of the tubular
member, wherein the positioning of the plurality of cement
diverters provides zonal communication interruption about every 10
to 20 feet (about every 3.0 to about 6.1 meters) axially along the
tubular member.
[0065] Also disclosed herein is a method of producing hydrocarbons
from a production well of an underground formation, comprising the
steps of: installing a tubular member into a wellbore of an
underground formation, the tubular member having a plurality of
cement diverters positioned axially along an outer surface of the
tubular member, each cement diverter having an axial length and an
azimuthal extension of less than 360.degree., wherein the azimuthal
position of at least one cement diverter is axially rotated from an
adjacent cement diverter; flowing cement into an annulus formed
between an inner surface of the wellbore and the outer surface of
the tubular member to form a production well; and producing fluids
containing hydrocarbons from the production well, wherein the
positioning of the plurality of cement diverters provides zonal
communication interruption about every 10 to 20 feet (about every
3.0 to about 6.1 meters) axially along the tubular member.
[0066] As used herein, the term "and/or" placed between a first
entity and a second entity means one of (1) the first entity, (2)
the second entity, and (3) the first entity and the second entity.
Multiple entities listed with "and/or" should be construed in the
same manner, i.e., "one or more" of the entities so conjoined.
Other entities may optionally be present other than the entities
specifically identified by the "and/or" clause, whether related or
unrelated to those entities specifically identified. Thus, as a
non-limiting example, a reference to "A and/or B," when used in
conjunction with open-ended language such as "comprising" may
refer, in one embodiment, to A only (optionally including entities
other than B); in another embodiment, to B only (optionally
including entities other than A); in yet another embodiment, to
both A and B (optionally including other entities). These entities
may refer to elements, actions, structures, steps, operations,
values, and the like.
[0067] As used herein, the phrase "at least one," in reference to a
list of one or more entities should be understood to mean at least
one entity selected from any one or more of the entity in the list
of entities, but not necessarily including at least one of each and
every entity specifically listed within the list of entities and
not excluding any combinations of entities in the list of entities.
This definition also allows that entities may optionally be present
other than the entities specifically identified within the list of
entities to which the phrase "at least one" refers, whether related
or unrelated to those entities specifically identified. Thus, as a
non-limiting example, "at least one of A and B" (or, equivalently,
"at least one of A or B," or, equivalently "at least one of A
and/or B") may refer, in one embodiment, to at least one,
optionally including more than one, A, with no B present (and
optionally including entities other than B); in another embodiment,
to at least one, optionally including more than one, B, with no A
present (and optionally including entities other than A); in yet
another embodiment, to at least one, optionally including more than
one, A, and at least one, optionally including more than one, B
(and optionally including other entities). In other words, the
phrases "at least one," "one or more," and "and/or" are open-ended
expressions that are both conjunctive and disjunctive in operation.
For example, each of the expressions "at least one of A, B and C,"
"at least one of A, B, or C," "one or more of A, B, and C," "one or
more of A, B, or C" and "A, B, and/or C" may mean A alone, B alone,
C alone, A and B together, A and C together, B and C together, A, B
and C together, and optionally any of the above in combination with
at least one other entity.
[0068] In the event that any patents, patent applications, or other
references are incorporated by reference herein and define a term
in a manner or are otherwise inconsistent with either the
non-incorporated portion of the present disclosure or with any of
the other incorporated references, the non-incorporated portion of
the present disclosure shall control, and the term or incorporated
disclosure therein shall only control with respect to the reference
in which the term is defined and/or the incorporated disclosure was
originally present.
[0069] As used herein the terms "adapted" and "configured" mean
that the element, component, or other subject matter is designed
and/or intended to perform a given function. Thus, the use of the
terms "adapted" and "configured" should not be construed to mean
that a given element, component, or other subject matter is simply
"capable of" performing a given function but that the element,
component, and/or other subject matter is specifically selected,
created, implemented, utilized, programmed, and/or designed for the
purpose of performing the function. It is also within the scope of
the present disclosure that elements, components, and/or other
recited subject matter that is recited as being adapted to perform
a particular function may additionally or alternatively be
described as being configured to perform that function, and vice
versa.
INDUSTRIAL APPLICABILITY
[0070] The apparatus and methods disclosed herein are applicable to
the oil and gas industry.
[0071] It is believed that the disclosure set forth above
encompasses multiple distinct inventions with independent utility.
While each of these inventions has been disclosed in its preferred
form, the specific embodiments thereof as disclosed and illustrated
herein are not to be considered in a limiting sense as numerous
variations are possible. The subject matter of the inventions
includes all novel and non-obvious combinations and subcombinations
of the various elements, features, functions and/or properties
disclosed herein. Similarly, where the claims recite "a" or "a
first" element or the equivalent thereof, such claims should be
understood to include incorporation of one or more such elements,
neither requiring nor excluding two or more such elements.
[0072] It is believed that the following claims particularly point
out certain combinations and subcombinations that are directed to
one of the disclosed inventions and are novel and non-obvious.
Inventions embodied in other combinations and subcombinations of
features, functions, elements and/or properties may be claimed
through amendment of the present claims or presentation of new
claims in this or a related application. Such amended or new
claims, whether they are directed to a different invention or
directed to the same invention, whether different, broader,
narrower, or equal in scope to the original claims, are also
regarded as included within the subject matter of the inventions of
the present disclosure.
* * * * *