Note: Descriptions are shown in the official language in which they were submitted.
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SELECTIVE STIMULATION PORTS, WELLBORE TUBULARS THAT INCLUDE
SELECTIVE STIMULATION PORTS, AND METHODS OF OPERATING THE
SAME
Cross Reference To Related Applications
[0001] This application claims the benefit of U.S. Provisional
Application No.
62/262,034 filed December 2, 2015, entitled, "Selective Stimulation Ports,
Wellbore
Tubulars That Include Selective Stimulation Ports, and Methods of Operating
the Same," the
disclosure of which is incorporated herein by reference in its entirety.
[0002] This application is related to U.S. Provisional Application Serial
No. 62/262,036
filed December 2, 2015, entitled, "Wellbore Tubulars Including A Plurality of
Selective Ports
and Methods of Utilizing the Same," (Attorney Docket No. 2015EM361); U.S.
Provisional
Application Serial No. 62/263,065 filed December 4, 2015, entitled, "Wellbore
Ball Sealer
and Methods of Utilizing the Same," (Attorney Docket No. 2015EM369); U.S.
Provisional
Application Serial No. 62/263,067 filed December 4, 2015, entitled, "Ball-
Sealer Check-
Valves for Wellbore Tubulars and Methods of Utilizing the Same," (Attorney
Docket No.
2015EM370); U.S. Provisional Application Serial No. 62/263,069 filed December
4, 2015,
entitled, "Select-Fire, Downhole Shockwave Generation Devices, Hydrocarbon
Wells That
Include the Shockwave Generation Devices, and Methods of Utilizing the Same,"
(Attorney
Docket No. 2015EM371); and U.S. Provisional Application Serial No. 62/329690
filed April
29, 2016, entitled, "System and Method for Autonomous Tools," (Attorney Docket
No.
2016EM104), the disclosures of which are incorporated herein by reference in
their entireties.
Field of the Disclosure
[0003] The present disclosure is directed generally to selective
stimulation ports, to
wellbore tubulars that include selective stimulation ports, and to methods of
operating the
same.
Background of the Disclosure
[0004] Hydrocarbon wells generally include a wellbore that extends from a
surface
region and/or that extends within a subterranean formation that includes a
reservoir fluid,
such as liquid and/or gaseous hydrocarbons. Often, it may be desirable to
stimulate the
subterranean formation to enhance production of the reservoir fluid therefrom.
Stimulation
of the subterranean formation may be accomplished in a variety of ways and
generally
includes supplying a stimulant fluid to the subterranean formation to increase
reservoir
contact. As an example, the stimulation may include supplying an acid to the
subterranean
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formation to acid-treat the subterranean formation and/or to dissolve at least
a portion of the
subterranean formation. As another example, the stimulation may include
fracturing the
subterranean formation, such as by supplying a fracturing fluid, which is
pumped at a high
pressure, to the subterranean formation. The fracturing fluid may include
particulate
material, such as a proppant, which may at least partially fill fractures that
are generated
during the fracturing, thereby facilitating fluid flow within the fractures
after supply of the
fracturing fluid has ceased.
[0005] A variety of systems and/or methods have been developed to
facilitate stimulation
of subterranean formations, and each of these systems and methods generally
has inherent
to benefits and drawbacks. These systems and methods often utilize a shape
charge perforation
gun to create perforations within a casing string that extends within the
wellbore, and the
stimulant fluid then is provided to the subterranean formation via the
perforations. However,
such systems suffer from a number of limitations. As an example, the
perforations may not
be round or may have burrs, which may make it challenging to seal the
perforations
subsequent to stimulating a given region of the subterranean formation. As
another example,
the perforations often will erode and/or corrode due to flow of the stimulant
fluid, flow of
proppant, and/or long-term flow of reservoir fluid therethrough. This may make
it
challenging to seal the perforations and/or may change fluid flow
characteristics
therethrough. These challenges may occur early in the life of the hydrocarbon
well, such as
during and/or after completion thereof, and/or later in the life of the
hydrocarbon well, such
as after production of the reservoir fluid with the hydrocarbon well and/or
during and/or after
restimulation of the hydrocarbon well. As yet another example, it may be
challenging to
precisely locate, size, and/or orient perforations, which are created
utilizing the shape charge
perforation gun, within the casing string. Thus, there exists a need for
improved systems and
methods for stimulating a subterranean formation, such as may be facilitated
utilizing the
selective stimulation ports disclosed herein.
Summary of the Disclosure
[0006] Selective stimulation ports (SSPs), wellbore tubulars that include
the SSPs, and
methods of operating the same are disclosed herein. The SSPs are configured to
be
operatively attached to a wellbore tubular that defines a tubular conduit. The
wellbore
tubular is configured to extend within a wellbore that extends within a
subterranean
formation. The SSPs include an SSP body, an isolation device extending within
an SSP
conduit of the SSP body, a retention device coupling the isolation device to
the SSP body,
and a sealing device seat. The SSP body has a conduit-facing region and a
formation-facing
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region, and the SSP conduit extends between the conduit-facing region and the
formation-
facing region.
[0007] The isolation device is configured to selectively transition from
a closed state, in
which the isolation device restricts fluid flow through the SSP conduit, to an
open state, in
which the isolation device permits fluid flow through the SSP conduit. The
transition is
responsive to a shockwave, which has greater than a threshold shockwave
intensity, within a
wellbore fluid that extends within a tubular conduit of the wellbore tubular
and proximate the
SSP.
[0008] The retention device retains the isolation device in the closed
state prior to receipt
of the shockwave. The sealing device seat is defined by the conduit-facing
region of the SSP
body and is shaped to form a fluid seal with a sealing device, such as a ball
sealer, when the
sealing device is engaged with the sealing device seat. The fluid seal
selectively restricts
fluid flow from the tubular conduit to the subterranean formation via the SSP
conduit.
[0009] The methods include generating the shockwave within the wellbore
fluid such that
the shockwave has greater than the threshold shockwave intensity in a region
of the tubular
conduit that is proximal the SSP. The methods further include transitioning
the isolation
device from the closed state to the open state responsive to receipt of the
shockwave and
thereafter stimulating the subterranean formation proximate the conduit-facing
region of the
SSP.
Brief Description of the Drawings
[0010] Fig. 1 is a schematic representation of examples of a hydrocarbon
well that may
include and/or utilize selective stimulation ports, wellbore tubulars, and/or
methods according
to the present disclosure.
[0011] Fig. 2 is a schematic representation of selective stimulation
ports according to the
present disclosure.
[0012] Fig. 3 is a less schematic cross-sectional view of selective
stimulation ports
according to the present disclosure.
[0013] Fig. 4 is another less schematic cross-sectional view of selective
stimulation ports
according to the present disclosure.
[0014] Fig. 5 is another less schematic cross-sectional view of selective
stimulation ports
according to the present disclosure.
[0015] Fig. 6 is another less schematic cross-sectional view of a
selective stimulation port
according to the present disclosure installed on a wellbore tubular.
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[0016] Fig. 7 is a less schematic profile view of a selective stimulation
port according to
the present disclosure.
[0017] Fig. 8 is a view of a formation-facing side of the selective
stimulation port of Fig.
7.
[0018] Fig. 9 is a cross-sectional view of the selective stimulation port
of Figs. 7-8 taken
along line 9-9 of Fig. 8.
[0019] Fig. 10 is a flowchart depicting methods, according to the present
disclosure, of
stimulating a subterranean formation.
[0020] Fig. 11 is a schematic cross-sectional view of a portion of a
process flow for
stimulating a subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
[0021] Fig. 12 is a schematic cross-sectional view of a portion of the
process flow for
stimulating the subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
[0022] Fig. 13 is a schematic cross-sectional view of a portion of the
process flow for
stimulating the subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
[0023] Fig. 14 is a schematic cross-sectional view of a portion of the
process flow for
stimulating the subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
[0024] Fig. 15 is a schematic cross-sectional view of a portion of the
process flow for
stimulating the subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
[0025] Fig. 16 is a schematic cross-sectional view of a portion of the
process flow for
stimulating the subterranean formation utilizing the selective stimulation
ports, wellbore
tubulars, and/or methods according to the present disclosure.
Detailed Description and Best Mode of the Disclosure
[0026] Figs. 1-16 provide examples of selective stimulation ports (SSPs)
100, according
to the present disclosure, of wellbore tubulars 40 that include and/or utilize
the selective
stimulation ports, of hydrocarbon wells 10 that include and/or utilize the
wellbore tubulars,
and/or of methods 200 and/or process flows 300, according to the present
disclosure, for
stimulating a subterranean formation. Elements that serve a similar, or at
least substantially
similar, purpose are labeled with like numbers in each of Figs. 1-16, and
these elements may
not be discussed in detail herein with reference to each of Figs. 1-16.
Similarly, all elements
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may not be labeled in each of Figs. 1-16, but reference numerals associated
therewith may be
utilized herein for consistency. Elements, components, and/or features that
are discussed
herein with reference to one or more of Figs. 1-16 may be included in and/or
utilized with
any of Figs. 1-16 without departing from the scope of the present disclosure.
In general,
5 elements that are likely to be included in a particular embodiment are
illustrated in solid lines,
while elements that are optional are illustrated in dashed lines. However,
elements that are
shown in solid lines may not be essential and in some embodiments may be
omitted without
departing from the scope of the present disclosure.
[0027] Fig. 1 is a schematic representation of examples of a hydrocarbon
well 10 that
may include and/or utilize selective stimulation ports 100, wellbore tubulars
40, and/or
methods 200 according to the present disclosure. Hydrocarbon well 10 includes
a wellbore
that extends from a surface region 30, within a subsurface region 32, within a
subterranean
formation 34 of subsurface region 32, and/or between the surface region and
the subterranean
formation. Subterranean formation 34 includes a reservoir fluid 36, such as a
liquid
15 hydrocarbon and/or a gaseous hydrocarbon, and hydrocarbon well 10 may be
utilized to
produce, pump, and/or convey the reservoir fluid from the subterranean
formation and/or to
the surface region.
[0028] Hydrocarbon well 10 further includes wellbore tubular 40, which
extends within
wellbore 20 and defines a tubular conduit 42. Wellbore tubular 40 includes a
plurality of
20 selective stimulation ports (SSPs) 100, which are discussed in more
detail herein. SSPs 100
are illustrated in dashed lines in Fig. 1 to indicate that the SSPs may be
operatively attached
to and/or may form a portion of any suitable component of wellbore tubular 40.
[0029] Wellbore tubular 40 may include and/or be any suitable tubular
that may be
present, located, and/or extended within wellbore 20. As examples, wellbore
tubular 40 may
include and/or be a casing string 50 and/or inter-casing tubing 60, which may
be configured
to extend within the casing string. SSPs 100 may be configured to be
operatively attached to
wellbore tubular 40, such as to casing string 50 and/or inter-casing tubing
60, prior to the
wellbore tubular being located, placed, and/or installed within wellbore 20.
[0030] When wellbore tubular 40 includes casing string 50, SSPs 100 may
be operatively
attached to any suitable portion of the casing string. As examples, and as
illustrated, one or
more SSPs 100 may be operatively attached to one or more of a casing segment
52 of the
casing string, such as a sub or pup joint of the casing string, a casing
collar 54 of the casing
string, a blade centralizer 56 of the casing string, and/or a sleeve 58 that
extends around the
outer surface of the casing string.
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[0031] SSPs 100 may be operatively attached to wellbore tubular 40 in any
suitable
manner. As examples, SSPs 100 may be operatively attached to wellbore tubular
40 via one
or more of a threaded connection, a glued connection, a press-fit connection,
a welded
connection, and/or a brazed connection.
[0032] As illustrated in dashed lines in Fig. 1, hydrocarbon well 10 also
may include
and/or have associated therewith an optional shockwave generation device 190.
Shockwave
generation device 190 may be configured to generate a shockwave 194 within
tubular conduit
42, as discussed in more detail herein. Shockwave generation device 190 may
include and/or
be any suitable structure that may, or may be utilized to, generate the
shockwave within
tubular conduit 42. As an example, shockwave generation device 190 may be an
umbilical-
attached shockwave generation device 190 that may be operatively attached to,
or may be
positioned within tubular conduit 42 via, an umbilical 192, such as a
wireline, a tether,
tubing, and/or coiled tubing. As another example, shockwave generation device
190 may be
an autonomous shockwave generation device that may be flowed into and/or
within tubular
conduit 42 without an attached umbilical. As yet another example, the
shockwave generation
device may form a portion of one or more SSPs 100 and may be referred to as a
shockwave
generation structure 180, as discussed in more detail herein with reference to
Fig. 2. As
additional examples, shockwave generation device 190 may include an explosive
charge,
such as a length of primer cord and/or a blast cap. Primer cord also may be
referred to herein
as detonation cord and/or detonating cord and may be configured to explode
and/or detonate.
[0033] Figs. 2-9 provide examples of SSPs 100 according to the present
disclosure. Figs.
2-9 may be more detailed illustrations of SSPs 100 of Fig. 1, and any of the
structures,
functions, and/or features that are discussed and/or illustrated herein with
reference to any of
Figs. 2-9 may be included in and/or utilized with SSPs 100 of Fig. 1 without
departing from
the scope of the present disclosure. Similarly, any of the structures,
functions, and/or features
that are discussed and/or illustrated herein with reference to hydrocarbon
wells 10 and/or
wellbore tubulars 40 of Fig. 1 may be included in and/or utilized with SSPs
100 of Figs. 2-9
without departing from the scope of the present disclosure.
[0034] As illustrated in Figs. 2-5, SSPs 100 include an SSP body 110
including a conduit-
facing region 112, which is configured to face toward tubular conduit 42 when
SSP 100 is
installed within wellbore tubular 40. SSPs 100 also include a formation-facing
region 114,
which is configured to face toward subterranean formation 34 when the SSP is
installed
within the wellbore tubular and the wellbore tubular extends within the
subterranean
formation. SSP body 110 further includes and/or defines an SSP conduit 116,
which extends
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between conduit-facing region 112 and formation-facing region 114. As
discussed in more
detail herein, SSP conduit 116 may selectively establish a fluid flow path
between tubular
conduit 42 and subterranean formation 34.
[0035] SSP 100 also includes an isolation device 120. Isolation device
120 extends
within and/or across SSP conduit 116 and is configured to selectively
transition, or to be
selectively transitioned, from a closed state 121, as illustrated in Figs. 2-4
and 9, to an open
state 122, as illustrated in Figs. 3-6. When isolation device 120 is in closed
state 121, the
isolation device restricts, blocks, and/or occludes fluid flow within the SSP
conduit, through
the SSP conduit, and/or between tubular conduit 42 and subterranean formation
34 via the
SSP conduit. Conversely, and when isolation device 120 is in open state 122,
the isolation
device permits, facilitates, does not restrict, does not block, and/or does
not occlude the fluid
flow within the SSP conduit, through the SSP conduit, and/or between tubular
conduit 42 and
subterranean formation 34 via the SSP conduit. Transitioning isolation device
120 from the
closed state to the open state also may be referred to herein as transitioning
SSP 100 from the
closed state to the open state and/or as transitioning SSP conduit 116 from
the closed state to
the open state.
[0036] Isolation device 120 is configured to transition from the closed
state to the open
state responsive to, or responsive to experiencing, a shockwave that has
greater than a
threshold shockwave intensity. A shockwave that has greater than the threshold
shockwave
intensity may be referred to herein as a threshold shockwave, a triggering
shockwave, and/or
a transitioning shockwave. The shockwave may be generated by a shockwave
generation
structure 180, which may be present within and/or may form a portion of SSP
100 and is
illustrated in Fig. 2, and/or by a shockwave generation device 190, which may
be separated
and/or distinct from SSP 100 and is illustrated in Fig. 1. The shockwave may
be generated
within a wellbore fluid 22 and may be propagated from the shockwave generation
device or
the shockwave generation structure to the SSP via the wellbore fluid. Examples
of the
wellbore fluid include reservoir fluid 36 and/or a stimulant fluid, as
discussed in more detail
herein.
[0037] SSP 100 further includes a retention device 130, as illustrated in
Figs. 2-4 and 9.
Retention device 130 is configured to couple, or operatively couple, isolation
device 120 to
SSP body 110, such as to retain the isolation device in the closed state prior
to receipt of the
threshold shockwave. Retention device 130 optionally may be configured to
permit and/or
facilitate transitioning of isolation device 120 from the closed state to the
open state
responsive to receipt of the threshold shockwave.
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[0038] SSP 100 also includes a sealing device seat 140, as illustrated in
Figs. 2-5 and 9.
Sealing device seat 140 may be defined by conduit-facing region 112 of SSP
body 110. In
addition, sealing device seat 140 may be shaped to form a fluid seal 144 with
a sealing device
142, as illustrated in Figs. 2 and 9. The sealing device may be positioned on
and/or in contact
with the sealing device seat, such as to form the fluid seal, by flowing, via
tubular conduit 42,
into engagement with the sealing device seat. When the sealing device is
engaged with the
sealing device seat to form the fluid seal, the sealing device restricts, or
selectively restricts,
fluid flow from tubular conduit 42 to subterranean formation 34 via SSP
conduit 116.
[0039] As discussed in more detail herein, wellbore tubulars 40 may have
one or more
SSPs 100 operatively attached thereto prior to the wellbore tubular being
located, placed,
and/or positioned within the wellbore. The SSPs may be in the closed state
during operative
attachment to the wellbore tubular and/or while the wellbore tubular is
positioned within the
wellbore. Subsequently, shockwave generation structure 180 of Fig. 2 and/or
shockwave
generation device 190 of Fig. 1 may be utilized to generate the shockwave
within the
wellbore fluid that extends within the tubular conduit and/or that extends in
fluid
communication with the isolation device. The shockwave may propagate within
the wellbore
fluid and/or to the SSP and may be received and/or experienced by at least a
portion of the
one or more SSPs.
[0040] However, the shockwave also is attenuated, is dampened, and/or
decays as it
propagates within the wellbore fluid. Thus, the shockwave will only have
greater than the
threshold shockwave intensity within a specific region of the wellbore
tubular, and the one or
more SSPs will only transition from the closed state to the open state if the
one or more SSPs
is located within this specific region of the wellbore tubular (i.e., if the
shockwave has greater
than the threshold shockwave intensity when the shockwave reaches, or
contacts, the one or
more SSPs). Thus, individual, selected, and/or specific SSPs 100 may be
transitioned from
the closed state to the open state without transitioning, or concurrently
transitioning, other
SSPs that are outside, or that are not within, the specific region of the
wellbore tubular. Such
a configuration may permit SSPs 100, according to the present disclosure, to
be more
selectively actuated, via the shockwave, when compared to more universally
applied pressure
spikes, which may act upon an entirety of a length of the wellbore tubular.
[0041] The shockwave may be attenuated, within the wellbore fluid, at any
suitable (non-
zero) shockwave attenuation rate. As examples, the shockwave attenuation rate
may be at
least 1 megapascal per meter (MPa/m), at least 2 MPa/m, at least 4 MPa/m, at
least 6 MPa/m,
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at least 8 MPa/m, at least 10 MPa/m, at least 12 MPa/m, at least 14 MPa/m, at
least 16
MPa/m, at least 18 MPa/m, or at least 20 MPa/m.
[0042] The shockwave also may have any suitable (non-zero) shockwave
intensity, which
also may be referred to herein as a peak shockwave pressure and/or as a
maximum
shockwave pressure. As examples, the shockwave intensity may be at least 100
megapascals
(MPa), at least 110 MPa, at least 120 MPa, at least 130 MPa, at least 140 MPa,
at least 150
MPa, at least 160 MPa, at least 170 MPa, at least 180 MPa, at least 190 MPa,
at least 200
MPa, at least 250 MPa, at least 300 MPa, at least 400 MPa, or at least 500
MPa.
[0043] Similarly, the shockwave may have any suitable duration, which
also may be
referred to herein as a maximum duration, a shockwave duration, and/or a
maximum
shockwave duration. Examples of the maximum duration include durations of less
than 1
second, less than 0.9 seconds, less than 0.8 seconds, less than 0.7 seconds,
less than 0.6
seconds, less than 0.5 seconds, less than 0.4 seconds, less than 0.3 seconds,
less than 0.2
seconds, less than 0.1 seconds, less than 0.05 seconds, or less than 0.01
seconds. The
maximum duration may be a maximum period of time during which the shockwave
has
greater than the threshold shockwave intensity within the wellbore tubular.
Additionally or
alternatively, the maximum duration may be a maximum period of time during
which the
shockwave has a shockwave intensity of greater than 68.9 MPa (10,000 pounds
per square
inch) within the wellbore tubular.
[0044] With the above in mind, the shockwave may exhibit greater than the
threshold
shockwave intensity over only a fraction of a length of the wellbore tubular
and only for a
brief period of time. As examples, the shockwave may exhibit greater than the
threshold
shockwave intensity over a maximum effective distance of 1 meter, 2 meters, 3
meters, 4
meters, 5 meters, 6 meters, 7 meters, 8 meters, 10 meters, 15 meters, 20
meters, or 30 meters
along a length of the tubular conduit. Stated another way, the shockwave may
have a peak
shockwave intensity proximate an origination point thereof (i.e., proximate
the shockwave
generation device, the shockwave generation structure, and/or a shockwave
generation source
thereof). The threshold shockwave intensity may be less than, or less than a
threshold
fraction of, the peak shockwave intensity, and an intensity of the shockwave
may be less than
the threshold shockwave intensity at distances that are greater than the
maximum effective
distance from the origination point.
[0045] The shockwave generation structure and/or the shockwave generation
device may
be configured such that the shockwave emanates symmetrically, or at least
substantially
symmetrically, therefrom. Stated another way, the shockwave generation
structure and/or the
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shockwave generation device may be configured such that the shockwave emanates
isotropically, or at least substantially isotropically, therefrom. Stated yet
another way, the
shockwave generation structure and/or the shockwave generation device may be
configured
such that the shockwave is symmetric, or at least substantially symmetric,
within a given
5 transverse cross-section of the wellbore tubular.
[0046] SSP body 110 may include any suitable structure that may have,
include, and/or
define conduit-facing region 112, formation-facing region 114, and/or SSP
conduit 116. In
addition, SSP body 110 may be formed from any suitable material, and the SSP
body may be
formed from a different material than a material of wellbore tubular 40, than
a material of a
10 majority of wellbore tubular 40, and/or than a material that comprises a
portion of wellbore
tubular 40 that is operatively attached to SSP body 110.
[0047] It is within the scope of the present disclosure that SSP body 110
may be a single-
piece, or monolithic, SSP body 110. Alternatively, it also is within the scope
of the present
disclosure that SSP body 110 may be a composite SSP body 110 that may be
formed from a
plurality of distinct, separate, and/or chemically different components.
[0048] As illustrated in dashed lines in Fig. 2, SSP body 110 may be
separate from,
distinct from, and/or may be formed from a different material than wellbore
tubular 40.
Under these conditions, SSP body 110 may be configured to be operatively
attached to the
wellbore tubular with the SSP body extending through a tubular aperture 48
that may be
defined within the wellbore tubular and/or that may extend between tubular
conduit 42 and an
external surface 41 of the wellbore tubular. In such a configuration, SSP 100
and/or SSP
body 110 thereof may include a projecting region 150 that may be configured to
project past
tubular aperture 48. The projecting region may project transverse, or
perpendicular to, a
central axis 118 of SSP conduit 116. Stated another way, at least a portion of
SSP 100 and/or
SSP body 110 thereof may have a maximum outer diameter that is greater than an
inner
diameter of tubular aperture 48. In such a configuration, wellbore tubular 40
may define a
recess 46 that may be configured to receive projecting region 150.
[0049] Additionally or alternatively, SSP body 110 also may be at least
partially defined
by wellbore tubular 40 and/or by any suitable component thereof As examples,
SSP body
110 may be partially, or even completely, defined by casing string 50, casing
segment 52,
casing collar 54, blade centralizer 56, sleeve 58, and/or inter-casing tubing
60 of Fig. 1.
[0050] As illustrated in Fig. 2, SSP 100 and/or SSP body 110 thereof may
be configured
such that the SSP does not extend into tubular conduit 42 and/or such that the
SSP does not
extend, or project, past an internal surface 43 of wellbore tubular 40 that
defines tubular
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conduit 42. Stated another way, conduit-facing region 112 of SSP body 110
and/or sealing
device seat 140 of SSP 100 may be flush with internal surface 43 and/or may be
recessed
within tubular aperture 48, when present. Thus, SSP 100 may not block and/or
restrict fluid
flow within tubular conduit 42 and/or the presence of SSP 100 may not change a
transverse
cross-sectional area for fluid flow within tubular conduit 42.
[0051] Stated yet another way, a transverse cross-sectional area of a
portion of the tubular
conduit that includes one or more SSPs may be at least a threshold fraction of
a transverse
cross-sectional area of a portion of the tubular conduit that does not include
an SSP, or any
SSPs. Examples of the threshold fraction of the transverse cross-sectional
area include
threshold fractions of at least 80 percent, at least 85 percent, at least 90
percent, at least 92.5
percent, at least 95 percent, at least 96 percent, at least 97 percent, at
least 98 percent, or at
least 99 percent of the transverse cross-sectional area.
[0052] As discussed in more detail herein, conventional stimulation
methods may utilize
a shape charge perforation device to create, generate, and/or define one or
more perforations
within a casing string that extends within a subterranean formation. As also
discussed, such
perforations may not be symmetrical, may not be round, and/or may not form a
fluid-tight
seal with a sealing device, such as a ball sealer. In addition, and as also
discussed,
stimulation of the subterranean formation may include flowing a stimulant
fluid that may
include particulate material through the perforations, which may be abrasive
to the
perforations, and/or flowing a stimulant fluid that may include a corrosive
material through
the perforations, which may corrode the perforations. Additionally or
alternatively, long-
term flow of the reservoir fluid through the perforations also may corrode the
perforations.
Thus, flow of the stimulant fluid through the perforations further may change
the shape of the
perforations. This change in shape further may decrease an ability for the
perforations to
form a fluid-tight seal with the sealing device and/or may cause an increase
in a cross-
sectional area for fluid flow through the perforations, thereby increasing a
flow rate of the
stimulant fluid through the perforations for a given pressure drop
thereacross. Either
situation may be detrimental to, may decrease a reliability of, and/or may
increase a
complexity of stimulation operations that utilize perforations created by
shape charge
perforation devices.
[0053] With this in mind, SSPs 100 according to the present disclosure
may include an
SSP body 110 that is at least partially erosion-resistant and/or corrosion-
resistant, or at least
more erosion-resistant and/or corrosion-resistant than wellbore tubular 40. As
an example,
SSP body 110 may include and/or be an erosion-resistant SSP body that may be
configured to
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resist erosion by the particulate material. As a more specific example, the
SSP body may
include an erosion-resistant material that is more resistant to erosion than a
material forming
a portion of the wellbore tubular to which the SSP is attached. The erosion-
resistant material
may form at least a portion of any suitable region and/or component of SSP
body 110. As
examples, the erosion-resistant material may form at least a portion of
conduit-facing region
112, formation-facing region 114, sealing device seat 140, and/or an internal
portion of SSP
body 110 that defines SSP conduit 116.
[0054] It is within the scope of the present disclosure that the erosion-
resistant material
may form and/or define the entire, or an entirety of, SSP body 110.
Alternatively, it also is
within the scope of the present disclosure that the erosion-resistant material
may form only a
portion, a subset, or less than an entirety of the SSP body and/or that the
erosion-resistant
material may be different from a material of a remainder of the SSP body. As
an example,
the erosion-resistant material may include and/or be an erosion-resistant
sleeve 111 that is
operatively attached to the SSP body and/or an erosion-resistant coating 113
that covers at
least a portion of the SSP body. As another example, the erosion-resistant
material may
include and/or be an erosion-resistant layer, coating, and/or ring that is
operatively attached
to and/or forms all or a portion of sealing device seat 140.
[0055] As another example, SSP body 110 may include and/or be a corrosion-
resistant
SSP body that may be configured to resist corrosion by, within, or while in
contact with, the
stimulant fluid, such as a stimulant fluid that includes, or is, an acid. As a
more specific
example, the SSP body may include a corrosion-resistant material that is more
resistant to
corrosion than a material forming a portion of the wellbore tubular to which
the SSP is
attached. The corrosion-resistant material may form at least a portion of any
suitable region
and/or component of SSP body 110. As examples, the corrosion-resistant
material may form
at least a portion of conduit-facing region 112, formation-facing region 114,
sealing device
seat 140, and/or an internal portion of SSP body 110 that defines SSP conduit
116.
[0056] It is within the scope of the present disclosure that the
corrosion-resistant material
may form and/or define the entire, or an entirety of, the SSP body.
Alternatively, it is also
within the scope of the present disclosure that the corrosion-resistant
material may form only
a portion, a subset, or less than an entirety of the SSP body and/or that the
corrosion-resistant
material may be different from a material of a remainder of the SSP body. As
an example,
the corrosion-resistant material may include and/or be a corrosion-resistant
sleeve 111 that is
operatively attached to the SSP body and/or a corrosion-resistant coating 113
that covers at
least a portion of the SSP body. As another example, the corrosion-resistant
material may
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include and/or be a corrosion-resistant layer, coating, and/or ring that is
operatively attached
to and/or forms all or a portion of sealing device seat 140.
[0057] Examples of the erosion-resistant material, of the corrosion-
resistant material,
and/or of other materials that may be included within SSP body 110 include one
or more of a
nitride, a nitride coating, a boride, a boride coating, a carbide, a carbide
coating, a tungsten
carbide, a tungsten carbide coating, a self-hardening alloy, a work-hardening
alloy, high
manganese work-hardening steel, a ceramic, a high strength steel, a diamond-
like material, a
diamond-like coating, a heat-treated material, a magnetic material, and/or a
radioactive
material. When SSP body 110 includes and/or is formed from the magnetic
material and/or
the radioactive material, shockwave generation device 190 of Fig. 1 may be
configured to
detect and/or determine a proximity between SSP 100 and the shockwave
generation device
by detecting the presence of, or proximity to, the magnetic material and/or
the radioactive
material.
[0058] SSP conduit 116 may include and/or be any suitable fluid conduit
that extends
between the conduit-facing region and the formation-facing region and/or that
may be
configured to convey a fluid between the tubular conduit and the subterranean
formation
when isolation device 120 is in the open state. In addition, SSP conduit 116
may have any
suitable inner diameter, cross-sectional area, and/or transverse cross-
sectional area. As an
example, SSP conduit 116 may include and/or be a cylindrical, or at least
substantially
cylindrical, SSP conduit. The cylindrical SSP conduit may have a diameter of
at least 0.1
centimeter (cm), at least 0.15 cm, at least 0.2 cm, at least 0.25 cm, at least
0.5 cm, at least
0.75 cm, at least 1 cm, at least 1.5 cm, at least 2 cm, at least 2.5 cm, at
least 3 cm, or at least
3.5 cm. Additionally or alternatively, the cylindrical SSP conduit may have a
diameter of
less than 6 cm, less than 5.5 cm, less than 5 cm, less than 4.5 cm, less than
4 cm, less than 3.5
cm, less than 3 cm, or less than 2.5 cm.
[0059] Additionally or alternatively, the SSP conduit may have a diameter
that is less
than an average tubular conduit diameter of tubular conduit 42. As examples,
the SSP
conduit may have a diameter that is less than 20 percent, less than 15
percent, less than 10
percent, or less than 5 percent of the average tubular conduit diameter of
tubular conduit 42.
[0060] When SSP conduit 116 is not the cylindrical SSP conduit, a
transverse cross-
sectional area of the SSP conduit may be comparable, or equal, to the cross-
sectional areas of
cylindrical SSP conduits that have any of the above-listed diameters and/or
diameter ranges.
In addition, and when SSP conduits 116 of the plurality of SSPs 100 have
different and/or
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varying diameters, the plurality of SSPs may define an average SSP conduit
diameter, and the
average SSP conduit diameter may include any of the above-listed diameters.
[0061] Isolation device 120 may include and/or be any suitable structure
that may extend
within SSP conduit 116, that may selectively restrict fluid flow through the
SSP conduit,
and/or that may be configured to selectively transition from the closed state
to the open state
responsive to the threshold shockwave. In general, isolation device 120 may be
adapted,
configured, designed, and/or constructed only to exhibit a single, or
irreversible, transition
from the closed state to the open state. As examples, and as discussed in more
detail herein,
isolation device 120 may be configured to break apart, to be destroyed, to be
displaced from,
and/or to irreversibly separate from a remainder of SSP 100 and/or from SSP
body 110 upon
transitioning from the closed state to the open state.
[0062] Isolation device 120 may include and/or be formed from any
suitable material. As
examples, the isolation device may include and/or be formed from a magnetic
material, a
radioactive material, and/or an acid-soluble material. Additional examples of
materials of
isolation device 120 are disclosed herein. When isolation device 120 includes
and/or is
formed from the magnetic material and/or the radioactive material, these
materials may be
detected by shockwave generation device 190, as discussed herein.
[0063] As discussed, isolation device 120 may be configured to transition
from the closed
state to the open state responsive to the threshold shockwave, and examples of
the threshold
shockwave and the threshold shockwave intensity are disclosed herein.
Isolation device 120
also may be configured to remain in the closed state, or to resist
transitioning from the closed
state to the open state, during, or despite, a static pressure differential
thereacross. This static
pressure differential may have a significant magnitude, and examples of the
static pressure
differential, which also may be referred to herein as a threshold static
pressure differential,
include pressure differentials of at least 40 MPa, at least 45 MPa, at least
50 MPa, at least 55
MPa, at least 60 MPa, at least 65 MPa, at least 68 MPa, at least 68.9 MPa, at
least 70 MPa, at
least 75 MPa, at least 80 MPa, at least 85 MPa, at least 90 MPa, at least 95
MPa, or at least
100 MPa.
[0064] Isolation device 120 may be positioned, located, and/or present at
any suitable
location within SSP 100 and/or within SSP conduit 116 thereof As an example,
and as
illustrated in Fig. 2, isolation device 120 may be positioned within a central
portion of SSP
conduit 116, proximal a midpoint of a length of SSP conduit 116, and/or such
that the
isolation device is offset from conduit-facing region 112 and also from
formation-facing
region 114. As another example, and as illustrated in Fig. 3, isolation device
110 may be
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aligned with and/or proximal formation-facing region 114. As yet another
example, and as
illustrated in Fig. 4, isolation device 110 may be aligned with and/or
proximal conduit-facing
region 112.
[0065] Isolation device 120 also may have any suitable isolation device
thickness 127, as
5 illustrated in Fig. 2. As an example, isolation device thickness 127 may
be less than a
wellbore tubular thickness 44 of wellbore tubular 40. Both isolation device
thickness 127
and wellbore tubular thickness 44 may be measured in a direction that is
parallel to central
axis 118 of SSP conduit 116.
[0066] As illustrated in Figs. 2-4, SSP body 110 may include and/or
define an isolation
it) device recess 119, which may be configured to receive isolation device
120. Isolation device
recess 119 may extend from conduit-facing region 112 of SSP body 110, as
illustrated
schematically in Fig. 2 and less schematically in Fig. 4. Additionally or
alternatively,
isolation device recess 119 also may extend from formation-facing region 114
of SSP body
110, as illustrated schematically in Fig. 2 and less schematically in Fig. 3.
When SSP body
15 110 includes isolation device recess 119, retention device 130 may be
configured to at least
temporarily retain the isolation device within the isolation device recess, as
also illustrated in
Figs. 2-4.
[0067] Isolation device 120 also may have and/or define any suitable
shape. As an
example, a shape of an outer perimeter of isolation device 120 may be
complementary to, or
may correspond to, a transverse cross-sectional shape of isolation device
recess 119, when
present, and/or to a transverse cross-sectional shape of SSP conduit 116. As
another
example, and as illustrated in Fig. 2, isolation device 120 may include a
conduit-facing side
128 and a formation-facing side 129, and the conduit-facing side and/or the
formation-facing
side may be planar, at least substantially planar, arcuate, partially
spherical, partially
parabolic, partially cylindrical, and/or partially hyperbolic. Stated another
way, isolation
device 120 may have a non-constant thickness as measured in a direction that
extends
between conduit-facing region 112 and formation-facing region 114 of SSP body
110 and/or
as measured in a direction that is parallel to central axis 118.
[0068] In general, the shape of the isolation device may be selected such
that the isolation
device is shaped to resist at least a threshold static pressure differential
between conduit-
facing side 128 and formation-facing side 129 without damage thereto. Examples
of the
threshold static pressure differential are disclosed herein.
[0069] An example of isolation device 120 is an isolation disk 126, as
illustrated in Figs.
2-3. As illustrated in dashed lines in Fig. 3, isolation disk 126 may be
configured to be
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retained within SSP 100 by retention device 130 when the isolation device is
in closed state
121. However, and as illustrated in dash-dot lines, isolation disk 120 may be
configured
separate from a remainder of SSP 100 and/or to be displaced or otherwise
conveyed into
subterranean formation 34 in an intact, or at least substantially intact,
state when the isolation
device transitions to open state 122. This may include the isolation disk
being conveyed from
formation-facing region 114 of SSP body 110 and/or being conveyed from a
formation-facing
end of SSP conduit 116, with the formation-facing end of the SSP conduit being
defined by
formation-facing region 114. Isolation disk 126 may include any suitable
material and/or
materials of construction, examples of which include a metallic isolation disk
that may be
formed from one or more of steel, stainless steel, cast iron, a metal alloy,
brass, and/or
copper. When SSPs 100 include isolation disk 126 of Figs. 2-3, and as
discussed in more
detail herein, retention device 130 may be configured to selectively release
the isolation disk
from the SSP responsive to the threshold shockwave.
[0070] Another example of isolation device 120 is a frangible isolation
device 120 that is
formed from a frangible material. The frangible material may be configured to
break apart,
to be destroyed, and/or to disintegrate responsive to, responsive to
experiencing, and/or
responsive to receipt of the threshold shockwave. Such an isolation device
also may be
referred to herein as a frangible disk 125 and/or as a frangible isolation
disk 125 and is
illustrated in Figs. 2 and 4. Examples of the frangible material include a
glass, a tempered
glass, a ceramic, a frangible magnetic material, a frangible radioactive
material, a frangible
ceramic magnet, a frangible alloy, and/or an acrylic.
[0071] Additionally or alternatively, isolation device 120 may include
and/or be formed
from an explosive material that is configured to detonate and/or explode
responsive to,
responsive to experiencing, and/or responsive to receipt of the threshold
shockwave. An
isolation device 120 with this explosive material may be referred to as an
explosive isolation
device 120. Examples of explosive material that may be utilized include a
solid explosive
material, a brittle explosive material, a frangible explosive material, and/or
a solid rocket
fuel. The explosive material also may be referred to herein as an accelerant
that accelerates
stimulation of the subterranean formation due to the resulting explosion and
generation of
gases that promote greater fracture initiation and/or stimulation of the
subterranean
formation.
[0072] As discussed, frangible isolation devices 120, such as frangible
disks 125, may be
configured to break apart responsive to receipt of the threshold shockwave. As
an example,
and as illustrated in Fig. 4, such isolation devices may comprise a single
piece prior to receipt
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of the threshold shockwave (as illustrated in dashed lines) and may comprise a
plurality of
spaced-apart pieces subsequent to receipt of the threshold shockwave (as
illustrated in dash-
dot lines). As another example, and when the isolation device is in closed
state 121 (i.e.,
prior to receipt of the threshold shockwave), the isolation device may define
a first maximum
dimension 156, such as an outer diameter 124. Conversely, and when the
isolation device is
in open state 122 (i.e., subsequent to receipt of the threshold shockwave),
the isolation device
may define a second maximum dimension 158 that is less than the first maximum
dimension.
As further illustrated in Fig. 4, and while in closed state 121, outer
diameter 124 of isolation
device 120 may be greater than a minimum outer diameter 159 of SSP conduit
116.
However, when in open state 122, second maximum dimension 158 may be less than
minimum outer diameter 159.
[0073] Returning to Fig. 2, and as illustrated in dashed lines, SSP 100
may include a
sealing structure 196. Sealing structure 196 may be configured to restrict
fluid flow within
SSP conduit 116 and past isolation device 120 when the isolation device is in
closed state
121. As examples, sealing structure 196 may be configured to form a fluid seal
between
isolation device 120 and SSP body 110 and/or between isolation device 120 and
retention
device 130. Examples of sealing structure 196 include any suitable elastomeric
sealing
structure, polymeric sealing structure, compliant sealing structure, flexible
sealing structure,
compressible sealing structure, a resin, an epoxy, an adhesive, a gasket,
and/or an 0-ring.
[0074] It is within the scope of the present disclosure that SSP 100 may
include a single
isolation device 120 or a plurality of isolation devices 120. As an example,
SSP 100 may
include a first isolation device 120, which may be configured to restrict
fluid flow from
conduit-facing region 112 and through SSP conduit 116, and a second isolation
device 120,
which may be configured to restrict fluid flow from formation-facing region
114 and through
SSP conduit 116.
[0075] When SSP 100 includes the first isolation device and the second
isolation device,
an intermediate portion of SSP conduit 116 may extend between, or separate,
the first
isolation device and the second isolation device. Under these conditions, the
first isolation
device may be configured to resist at least a first threshold static pressure
differential between
the tubular conduit and the intermediate portion of the SSP conduit.
Similarly, the second
isolation device may be configured to resist at least a second threshold
static pressure
differential between the subterranean formation and the intermediate portion
of the SSP
conduit. Examples of the first threshold static pressure differential and of
the second
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threshold static pressure differential are disclosed herein with reference to
the threshold static
pressure differential of isolation devices 120.
[0076] Retention device 130 may include and/or be any suitable structure
that may be
adapted, configured, shaped, and/or selected to couple the isolation device to
the SSP body
and/or to retain the isolation device in the closed state prior to receipt of
the threshold
shockwave. It is within the scope of the present disclosure that, responsive
to receipt of the
threshold shockwave, retention device 130 may be configured to release
isolation device 120
from SSP 100, such as when isolation device 120 includes isolation disk 126 of
Figs. 2-3.
Under these conditions, retention device 130 may change, transition, and/or be
deformed
upon receipt of the threshold shockwave. As an example, retention device 130
may include
at least one shear pin that shears, upon receipt of the threshold shockwave,
to release the
isolation device. As another example, retention device 130 may include at
least one snap ring
and corresponding groove, and the snap ring may be displaced from the groove,
upon receipt
of the threshold shockwave, to release the isolation device. As yet another
example, retention
device 130 may include a threaded retainer, and the threaded retainer may
fail, upon receipt
of the threshold shockwave, to release the isolation device.
[0077] Additionally or alternatively, it also is within the scope of the
present disclosure
that retention device 130 may be rigid, may be fixed, may be nonresponsive to
(i.e. not
damaged by) receipt of the threshold shockwave, and/or may not respond to the
threshold
shockwave, such as when isolation device 120 includes frangible disk 125 of
Figs. 2 and 4.
Under these conditions, isolation device 120 may fragment, fail, or otherwise
be displaced
from the retention device and the SSP body upon transitioning from the closed
state to the
open state, as illustrated in Fig. 4.
[0078] At least a portion of retention device 130 may be separate and/or
distinct from
SSP body 110. Additionally or alternatively, at least a portion of retention
device 130 may be
defined by SSP body 110. As an example, isolation device recess 119 of Figs. 2-
4 may form
a portion of retention device 130 and/or may at least partially retain
isolation device 120
within SSP 100.
[0079] Retention device 130 may include and/or be formed from any
suitable material
and/or materials, including a magnetic material and/or a radioactive material.
Such materials
may be detected by shockwave generation device 190, as discussed herein.
[0080] Sealing device seat 140 may include any suitable structure that
may be defined by
conduit-facing region 112 of SSP body 110 and/or that may be adapted,
configured, designed,
constructed, and/or shaped to form the fluid seal with the sealing device. In
addition, sealing
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device seat 140 may have a preconfigured, pre-established, and/or preselected
geometry, such
as when the geometry of the sealing device seat is established prior to SSP
100 being
operatively attached to wellbore tubular 40 and/or prior to the wellbore
tubular being located,
installed, and/or positioned within the subterranean formation. Sealing device
seat 140 may
be erosion-resistant, may be formed from the erosion-resistant material, may
be corrosion-
resistant, and/or may be formed from the corrosion-resistant material, as
discussed herein.
Additionally or alternatively, sealing device seat 140 may be defined by a
seat body, which
may form a portion of SSP body 110 and/or may be erosion-resistant, may be
formed from
the erosion-resistant material, may be corrosion-resistant, and/or may be
formed from the
corrosion-resistant material.
[0081] Sealing device seat 140 may have, define, and/or include any
suitable shape, and
the sealing device seat is illustrated in dashed lines in Figs. 2-3 to
illustrate several of these
potential shapes. In general, sealing device seat 140 may include and/or be a
symmetrical
sealing device seat. Examples of the sealing device seat and/or of a shape
thereof include a
partially spherical sealing device seat, a truncated spherical cap sealing
device seat, a conic
section sealing device seat, an at least partially cone-shaped sealing device
seat, an at least
partially funnel-shaped sealing device seat, and/or a tapered sealing device
seat. It is within
the scope of the present disclosure that the shape of the sealing device seat
of each of the
plurality of SSPs may be similar, or at least substantially similar. However,
this is not
required.
[0082] As an additional example, and as illustrated in Fig. 2, the
sealing device seat may
converge, within SSP body 110, from a first diameter 148, which is defined in
conduit-facing
region 112 of SSP body 110, to a second diameter 149, which is defined within
SSP body
110. The first diameter may be greater than the second diameter, and the
second diameter
may approach, or be, an outer diameter 117 of SSP conduit 116, which also may
be referred
to herein as an SSP conduit diameter 117. However, this is not required to all
embodiments.
[0083] As illustrated in Fig. 2, sealing device 142 may be operatively
positioned and/or
engaged with sealing device seat 140 to form fluid seal 144. An example of
sealing device
142 includes a ball sealer 143. When sealing device 142 includes ball sealer
143, sealing
device seat 140 also may be referred to herein as a ball sealer seat 141, and
ball sealer seat
141 may have a ball sealer seat radius of curvature that is equal, or at least
substantially
equal, to a ball sealer radius of ball sealer 143.
[0084] As discussed, SSPs 100 may include and/or be associated with
shockwave
generation structure 180, which may be adapted, configured, designed, and/or
constructed to
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generate the shockwave. Shockwave generation structure 180 may include and/or
be any
suitable structure. As examples, shockwave generation structure 180 may
include a
mechanical shockwave generation structure, such as may be configured to
mechanically
generate the shockwave, a chemical shockwave generation structure, such as may
be
5 configured to chemically generate the shockwave, and/or an explosive
shockwave generation
structure, and such as may be configured to explosively generate the
shockwave. When SSPs
100 include shockwave generation structure 180, the SSPs further may include a
triggering
device 182, which may be configured to actuate the shockwave generation
structure, such as
to cause the shockwave generation structure to generate the shockwave.
Examples of
10 triggering device 182 include any suitable wireless, or wirelessly
actuated, triggering device,
remote, or remotely actuated, triggering device, and/or wired triggering
device.
[0085] As illustrated in dashed lines in Fig. 2, SSP 100 further may
include a transition
assist structure 186. Transition assist structure 186 may be configured to
assist and/or
facilitate isolation device 120 transitioning from the closed state to the
open state responsive
15 to experiencing the threshold shockwave and may include any suitable
structure. As an
example, transition assist structure 186 may include and/or be a point load,
on isolation
device 120, that is configured to initiate failure of the isolation device
responsive to receiving
the threshold shockwave. As another example, transition assist structure 186
may include
and/or be a weak point on and/or within isolation device 120 that is
configured to initiate
20 failure of the isolation device responsive to receiving the threshold
shockwave.
[0086] As also illustrated in dashed lines in Fig. 2, SSP 100 may include
a barrier
material 170. Barrier material 170 may extend at least partially within SSP
conduit 116 and
may be configured to remain within the SSP conduit during installation of
wellbore tubular
40 into the subterranean formation. Such a configuration may protect SSP 100
and/or
isolation device 120 thereof from damage during the installation and/or may
prevent foreign
material from entering at least a portion of the SSP conduit during the
installation. In
addition, barrier material 170 also may be configured to automatically
separate, such as by
dissolving, from SSP 100 and/or from SSP conduit 116 thereof responsive, or
subsequent, to
fluid contact with the wellbore fluid.
[0087] Barrier material 170 may be placed and/or present within any
suitable portion of
SSP conduit 116. As an example, the barrier material may extend between
isolation device
120 and conduit-facing region 112 of SSP body 110. As another example, the
barrier
material may extend between isolation device 120 and formation-facing region
114 of SSP
body 110.
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[0088] Barrier material 170 may include any suitable material and/or
materials. As an
example, the barrier material may be selected to be, or may be, soluble within
the wellbore
fluid. More specific examples of barrier material 170 include polyglycolic
acid and/or
polylactic acid. As another example, barrier material 170 may include and/or
be an explosive
material. The explosive material may be configured to detonate and/or explode
responsive
to, responsive to experiencing, and/or responsive to receipt of the threshold
shockwave.
Examples of the explosive material are disclosed herein.
[0089] As illustrated in dashed lines in Fig. 2 and in solid lines in
Figs. 5-6, SSP 100 also
may include a nozzle 160. Nozzle 160 may be configured to generate a fluid jet
166, as
it) illustrated in Figs. 5-6, at formation-facing region 114 of SSP body
110 and/or at a
formation-facing end of SSP conduit 116. The fluid jet may be generated
responsive to fluid
flow from tubular conduit 42 and/or into subterranean formation 34 via the SSP
conduit.
[0090] Nozzle 160 may include any suitable structure. As an example,
nozzle 160 may
include and/or be a jet nozzle. As another example, nozzle 160 may include a
restriction, or a
restriction region, 161 that may be configured to accelerate the fluid flow,
as illustrated in
Fig. 2. Similarly, nozzle 160 may be formed from any suitable material,
examples of which
are disclosed herein with reference to the erosion-resistant materials and/or
the corrosion-
resistant materials of SSP body 110.
[0091] As illustrated in Fig. 5, nozzle 160 may include a gimbal
structure 162. Gimbal
structure 162 may be configured to permit rotation of nozzle 160 and/or of
fluid jet 166. This
may include rotation of nozzle 160 and/or of fluid jet 166 about and/or around
central axis
118, such as at an angle of rotation 164. This rotation of nozzle 160 and/or
of fluid jet 166
may be responsive to and/or powered by the fluid flow through SSP conduit 116.
[0092] As illustrated in Fig. 6, nozzle 160 additionally or alternatively
may include a
rotation structure 168. Rotation structure 168 may be configured to permit
rotation of nozzle
160 about an outer circumference of wellbore tubular 40. Under these
conditions, and as
illustrated, nozzle 160 may be oriented at an angle such that fluid jet 166
generates a torque
that provides a motive force for the rotation of the nozzle about and/or
around the outer
circumference of the wellbore tubular. Such motion of the nozzle may create a
groove, slot,
and/or channel within the subterranean formation. This groove, slot, and/or
channel may
extend away from the wellbore tubular and/or may extend perpendicularly, or at
least
substantially perpendicularly, from the wellbore tubular.
[0093] Returning more generally to Figs. 2 and 5-6, nozzle 160 may be
present within
any suitable portion of SSP 100 and/or within wellbore tubulars 40 that
include SSP 100. As
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an example, nozzle 160 may be proximal, or may form a portion of, formation-
facing region
114 of SSP body 110 and/or may be proximal, or may form a portion of, the
formation-facing
end of SSP conduit 116. As another example, nozzle 160 may be distal, or
relatively distal,
conduit-facing region 112 of SSP body 110 and/or a conduit-facing end of SSP
conduit 116.
As yet another example, nozzle 160 may extend outward from an outer surface of
wellbore
tubular 40.
[0094] Fig. 7 is a less schematic profile view of a selective stimulation
port (SSP) 100
according to the present disclosure, while Fig. 8 is a view of a formation-
facing side of the
SSP of Fig. 7 and Fig. 9 is a cross-sectional view of the SSP of Figs. 7-8
taken along line 9-9
of Fig. 8. SSP 100 of Figs. 7-9 may include and/or be a more detailed
illustration of SSPs
100 of Figs. 1-6, and any of the structures, functions, and/or features
discussed herein with
reference to any of Figs. 1-6 may be included in and/or utilized with SSP 100
of Figs. 7-9
without departing from the scope of the present disclosure. Similarly, any of
the structures,
functions, and/or features of SSP 100 of Figs. 7-9 may be included in and/or
utilized with
SSPs 100 of Figs. 1-6 without departing from the scope of the present
disclosure.
[0095] As illustrated in Figs. 7-9, SSP 100 includes an SSP body 110 that
defines an SSP
conduit 116. SSP body 110 has a conduit-facing region 112 and an opposed
formation-facing
region 114. SSP body 110 also has a projecting region 150, which projects from
SSP body
110 in a direction that is away from, or perpendicular to, a central axis 118
of SSP conduit
116.
[0096] SSP 100 also includes a tool-receiving portion 176, which may be
configured to
receive a tool during operative attachment of the SSP to a wellbore tubular,
and an
attachment region 178, which may be configured to interface with the wellbore
tubular when
the SSP is operatively attached to the wellbore tubular. As an example,
attachment region
178 may include threads, and SSP 100 may be configured to be rotated, via
receipt of the tool
within tool-receiving portion 176, to permit threading of the SSP into the
wellbore tubular.
[0097] As perhaps illustrated most clearly in Fig. 9, SSP 100 further
includes a sealing
device seat 140, which may be configured to receive a sealing device 142, and
an isolation
device 120. In Fig. 9, isolation device 120 is illustrated in closed state
121.
[0098] Fig. 10 is flowchart depicting methods 200, according to the present
disclosure, of
stimulating a subterranean formation, while Figs. 11-16 are schematic cross-
sectional views
of steps in a process flow 300 for stimulating a subterranean formation.
Process flow 300
may be an illustration of methods 200, and methods 200 and/or process flow 300
may be
performed utilizing selective stimulation ports 100 according to the present
disclosure, such
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as SSPs 100 of Figs. 1-9, and/or wellbore tubulars 40 that include the
selective stimulation
ports.
[0099] Methods 200 may include positioning a shockwave generation device
at 205
and/or changing a pressure within a tubular conduit at 210. Methods 200
include generating
a shockwave at 215 and may include propagating the shockwave at 220 and/or
attenuating the
shockwave at 225. Methods 200 further include transitioning an isolation
device at 230 and
may include flowing a stimulant fluid into a subterranean formation at 235,
stimulating the
subterranean formation at 240, flowing a sealing device at 245, repeating at
least a portion of
the methods at 250, and/or producing a reservoir fluid from the subterranean
formation at
255.
[0100] Positioning the shockwave generation device at 205 may include
positioning the
shockwave generation device within the tubular conduit and/or proximal to a
selective
stimulation port (SSP) that includes the isolation device. As an example, and
as illustrated in
Fig. 11, a tubular conduit 42 of a wellbore tubular 40 that extends within a
subterranean
formation 34 may not have and/or include a shockwave generation device prior
to the
positioning at 205. Additionally or alternatively, the shockwave generation
device may not
be positioned near and/or proximal an SSP 100 that is to be transitioned
during the
transitioning at 230 and/or responsive to the generating at 215. However, and
as illustrated in
Fig. 12, the tubular conduit may include shockwave generation device 190
and/or shockwave
generation device 190 may be oriented near and/or proximal the SSP 100
subsequent to the
positioning at 205.
[0101] The positioning at 205 may be accomplished in any suitable manner.
As an
example, the positioning at 205 may include flowing the shockwave generation
device into
proximity with the SSP. This may include flowing from a surface region, such
as surface
region 30 of Fig. 1, and/or flowing along the tubular conduit. The positioning
at 205 further
may include detecting a proximity of the shockwave generation device to the
SSP. This may
include detecting one or more properties of the SSP, detecting a material of
the SSP, and/or
detecting one or more properties of a portion of the wellbore tubular to which
the SSP is
operatively attached. As an example, the detecting may include detecting a
casing collar,
such as via and/or utilizing a casing collar locator. As another example, and
as discussed, the
SSP may include a magnetic material and/or a radioactive material, and the
detecting may
include detecting the magnetic material and/or the radioactive material.
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[0102] As discussed herein with reference to Fig. 1, SSPs 100 according
to the present
disclosure may include a built-in shockwave generation structure 180. Under
these
conditions, methods 200 may be performed without performing the positioning at
205.
[0103] Changing the pressure within the tubular conduit at 210 may
include increasing a
pressure within the tubular conduit. Additionally or alternatively, the
changing at 210 may
include decreasing the pressure within the tubular conduit.
[0104] When the changing at 210 includes increasing the pressure within
the tubular
conduit, the increasing may include pressurizing with a stimulant fluid and/or
pressurizing to
at least a threshold stimulation pressure. As an example, the increasing the
pressure may
include increasing to permit and/or facilitate the stimulating at 240.
Examples of the
threshold stimulation pressure include pressures, static pressures, or static
stimulation
pressures of at least 10 MPa, at least 15 MPa, at least 20 MPa, at least 25
MPa, at least 30
MPa, at least 35 MPa, at least 40 MPa, at least 45 MPa, at least 50 MPa, at
least 55 MPa, or
at least 60 MPa. Examples of the stimulant fluid include a water-based
stimulant fluid, an
oil-based stimulant fluid, an acid, and/or a fracturing fluid. The stimulant
fluid may include a
proppant.
[0105] When the changing at 210 includes decreasing the pressure within
the tubular
conduit, the decreasing may include at least partially evacuating the tubular
conduit and/or
removing at least a portion, a majority, or even substantially all liquid from
the tubular
conduit. As an example, decreasing the pressure may include decreasing to
permit and/or
facilitate an inrush of reservoir fluid into the tubular conduit subsequent to
the transitioning at
230. Such an inrush of reservoir fluid may flush, clear, and/or otherwise
remove debris
and/or particulate matter from the subterranean formation, thereby decreasing
a resistance to
fluid flow through the subterranean formation.
[0106] As discussed in more detail herein, the SSPs may be configured to
remain in a
closed state and/or to resist transitioning from the closed state to an open
state when a
pressure differential across an isolation device thereof is less than a
threshold static pressure
differential. In general, the threshold static pressure differential is
greater than the threshold
stimulation pressure and/or is greater than a pressure differential across the
isolation device
that may be generated during the changing at 210 and/or prior to the
generating at 215.
Examples of pressure differentials that may be generated prior to the
generating at 215
include external pressure swings during running of the wellbore tubular,
pressure differentials
generated during wellbore tubular pressure testing, pressure differentials
generated during
stimulation of the subterranean formation, and/or pressure differentials
generated during
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evacuation of all fluids from the wellbore tubular, such as to generate an
underbalanced
condition. As such, methods 200 further may include retaining the isolation
device in the
closed state during the changing at 210 and/or prior to the generating at 215.
Examples of the
threshold static pressure differential are disclosed herein.
5 [0107]
Generating the shockwave at 215 may include generating the shockwave within
a
wellbore fluid that extends within the tubular conduit. In addition, the
generating at 215 may
include generating within a region of the tubular conduit that is proximal the
SSP such that a
magnitude of the shockwave is greater than a threshold shockwave intensity
that is sufficient
to transition the isolation device of the SSP from the closed state to the
open state (i.e., such
10 that the SSP receives and/or experiences the threshold shockwave). This
is illustrated in Fig.
13 by the generation of a shockwave 194 with shockwave generation device 190.
[0108] The
generating at 215 may be accomplished in any suitable manner. As an
example, the generating at 215 may include detonating an explosive charge
within the tubular
conduit. The explosive charge may be associated with and/or may form a portion
of the
15 shockwave generation device, which is separate from the SSP, and/or may
be associated with
and/or may form a portion of the shockwave generation structure, which forms a
portion of
the SSP. As another example, the generating at 215 may include actuating a
triggering
device, such as a blast cap. The actuating may include remotely actuating
and/or wirelessly
actuating the triggering device.
20 [0109]
When the generating at 215 includes generating with the shockwave generation
device, the shockwave generation device may be located within the tubular
conduit such that
the shockwave has greater than the threshold shockwave intensity within the
wellbore fluid
that extends within the tubular conduit and in contact with the isolation
device. In addition,
the shockwave may have less, may have decayed to less, and/or may have been
attenuated to
25 less than the threshold shockwave intensity at a distance that is
greater than a maximum
effective distance from the shockwave generation device. Examples of the
maximum
effective distance are disclosed herein.
[0110] It
is within the scope of the present disclosure that the generating at 215 may
include generating such that the shockwave emanates at least substantially
symmetrically
from the shockwave generation device and/or such that the shockwave emanates
at least
substantially isotropically from the shockwave generation device.
Additionally or
alternatively, the generating at 215 may include generating such that the
shockwave is
symmetrical, or at least substantially symmetrical, within a given transverse
cross-section of
the tubular conduit and/or such that the shockwave has a constant, or at least
substantially
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constant, magnitude within the given transverse cross-section of the tubular
conduit at a given
point in time.
[0111] The shockwave may have any suitable maximum shockwave pressure
and/or
maximum shockwave duration that is sufficient to transition the isolation
device from the
closed state to the open state but insufficient to cause damage to the
wellbore tubular.
Examples of the maximum shockwave pressure and/or of the maximum shockwave
duration
are disclosed herein.
[0112] Propagating the shockwave at 220 may include propagating in any
suitable
manner. As examples, the propagating at 220 may include propagating the
shockwave from
the shockwave generation device, propagating the shockwave to the SSP,
propagating the
shockwave to the isolation device of the SSP, and/or propagating the shockwave
in and/or
within the wellbore fluid.
[0113] Attenuating the shockwave at 225 may include attenuating the
shockwave in any
suitable manner. As examples, the attenuating at 225 may include attenuating
by and/or
within the wellbore fluid. This may include dissipating at least a portion of
the shockwave
within the wellbore fluid and/or absorbing energy from the shockwave with the
wellbore
fluid. The attenuating at 225 may include attenuating at any suitable
attenuation rate,
examples of which are disclosed herein.
[0114] Transitioning the isolation device at 230 may include
transitioning the isolation
device from the closed state to the open state and/or transitioning to permit
fluid
communication between the tubular conduit and the subterranean formation via
the SSP
conduit. The transitioning at 230 may be at least partially responsive to the
generating at 215.
As an example, the transitioning may be initiated and/or triggered by receipt
of the threshold
shockwave with and/or by the isolation device.
[0115] The transitioning at 230 may be accomplished in any suitable manner.
As an
example, the transitioning at 230 may include shattering a frangible disk that
defines at least a
portion of the isolation device. As another example, the transitioning at 230
may include
displacing an isolation disk, which defines at least a portion of the
isolation device, from the
SSP conduit. The displacing may include shearing a pin that retains the
isolation disk within
the SSP conduit and/or defeating a clip that retains the isolation device
within the SSP
conduit.
[0116] Flowing the stimulant fluid into the subterranean formation at 235
may include
flowing subsequent to the transitioning at 230 and/or responsive to the
transitioning at 230.
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In addition, the flowing at 235 may include flowing to permit and/or
facilitate the stimulating
at 240.
[0117] As an example, and when methods 200 include the changing at 210
and the
changing at 210 includes pressurizing the tubular conduit, the stimulation
pressure within the
tubular conduit may provide a motive force for the flowing at 235, and the
transitioning at
230 may provide a fluid pathway for flow of the stimulant fluid. This is
illustrated in Fig. 14,
with SSP 100 in open state 122 and stimulant fluid 70 flowing from wellbore
tubular 42 into
subterranean formation 34 via SSP conduit 116 of the SSP.
[0118] As discussed herein, SSP 100 may include a nozzle, such as nozzle
160 of Figs. 2
and 5-6. Under these conditions, the flowing at 235 further may include
accelerating the
stimulant fluid with the nozzle.
[0119] Stimulating the subterranean formation at 240 may include
stimulating the
subterranean formation via the SSP conduit. As an example, and as discussed
herein with
reference to the flowing at 235, the stimulant fluid may flow from the tubular
conduit into the
subterranean formation via the SSP conduit. The stimulating at 240 may include
stimulating
in any suitable manner. As examples, the stimulating at 240 may include
fracturing the
subterranean formation, propping the subterranean formation, flushing the
subterranean
formation, acid treating the subterranean formation, and/or increasing a
surface area, a
surface contact area, and/or a permeability of the subterranean formation, as
indicated in Fig.
14 at 38.
[0120] Flowing the sealing device at 245 may include flowing any suitable
sealing device
via and/or along the tubular conduit and into contact and/or engagement with a
sealing device
seat of the SSP. This may include flowing to form a fluid seal between the
sealing device
and the sealing device seat and/or flowing to selectively restrict fluid flow
from the tubular
conduit and into the subterranean formation via the SSP conduit. This is
illustrated in Fig.
15. Therein, a sealing device 142 is illustrated as flowing into contact and
engaging with a
sealing device seat 140 of SSP 100. The flowing at 245 may include flowing
within and/or
via the stimulant fluid and/or may be performed subsequent to performing the
flowing at 235
for at least a threshold stimulation time.
[0121] Repeating at least the portion of the methods at 250 may include
repeating any
suitable portion of methods 200, such as to transition another isolation
device that may be
operatively attached to the wellbore tubular and/or to stimulate another
portion, zone, and/or
region of the subterranean formation. As an example, the wellbore tubular may
include a
plurality of spaced-apart SSPs, and the repeating at 250 may include repeating
at least the
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changing at 210, the generating at 215, the transitioning at 230, the flowing
at 235, and the
flowing at 245 to stimulate a portion of the subterranean formation that is
proximal a second
SSP of the plurality of SSPs. Additionally or alternatively, the repeating at
250 also may
include repeating a plurality of times to stimulate a plurality of portions of
the subterranean
formation, with each of the plurality of portions of the subterranean
formation associated with
a respective SSP of the plurality of SSPs.
[0122] Producing the reservoir fluid from the subterranean formation at
255 may include
producing in any suitable manner. As an example, the producing at 255 may
include flowing
the reservoir fluid from the subterranean formation and into the tubular
conduit via the SSP
conduit. As another example, the producing at 255 may include flowing the
reservoir fluid
via the tubular conduit, from the subterranean formation, and/or to the
surface region. The
producing at 255 is illustrated in Fig. 16. Therein, reservoir fluid 36 flows
from subterranean
formation 34 and into tubular conduit 42 via SSP conduit 116 of SSP 100.
[0123] In the present disclosure, several of the illustrative, non-
exclusive examples have
been discussed and/or presented in the context of flow diagrams, process
flows, or flow
charts, in which the methods are shown and described as a series of blocks, or
steps. Unless
specifically set forth in the accompanying description, it is within the scope
of the present
disclosure that the order of the blocks may vary from the illustrated order in
the flow
diagram, including with two or more of the blocks (or steps) occurring in a
different order
and/or concurrently.
[0124] 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.
[0125] 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
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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.
[0126] In the event that any patents, patent applications, or other
references are
incorporated by reference herein and (1) define a term in a manner that is
inconsistent with
and/or (2) are otherwise inconsistent with, either the non-incorporated
portion of the present
disclosure or 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 present originally.
[0127] 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. As used herein, the phrase, "for example," the
phrase, "as an
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example," and/or simply the term "example," when used with reference to one or
more
components, features, details, structures, embodiments, and/or methods
according to the
present disclosure, are intended to convey that the described component,
feature, detail,
structure, embodiment, and/or method is an illustrative, non-exclusive example
of
5 components, features, details, structures, embodiments, and/or methods
according to the
present disclosure. Thus, the described component, feature, detail, structure,
embodiment,
and/or method is not intended to be limiting, required, or
exclusive/exhaustive; and other
components, features, details, structures, embodiments, and/or methods,
including
structurally and/or functionally similar and/or equivalent components,
features, details,
10 structures, embodiments, and/or methods, are also within the scope of
the present disclosure.
Industrial Applicability
[0128] The selective stimulation ports, wellbore tubulars, and methods
disclosed herein
are applicable to the oil and gas industries.
[0129] It is believed that the disclosure set forth above encompasses
multiple distinct
15 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
20 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.
[0130] 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
25 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
30 regarded as included within the subject matter of the inventions of the
present disclosure.
