This disclosure relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an example described below, more particularly provides for forming inclusions in selected azimuthal orientations from a casing section.
It is beneficial to be able to form inclusions into subterranean formations. For example, such inclusions might be used to expose more formation surface area to a wellbore, increase permeability of the formation near the wellbore, etc.
Therefore, it will be appreciated that improvements are continually needed in the art of forming inclusions into earth formations.
In the disclosure below, systems and methods are provided which bring improvements to the art. One example is described below in which individual ones of multiple inclusions can be selectively extended into a formation. Another example is described below in which the inclusions can be isolated from each other while fluid is being flowed into one of the inclusions.
In one aspect, a method of forming multiple inclusions into a subterranean formation is provided to the art by the disclosure below. In one example, the method can include initiating the inclusions into the formation, the inclusions extending outwardly in respective multiple azimuthal orientations from a casing section; and flowing fluid into each of the inclusions individually, thereby extending the inclusions into the formation one at a time.
In another aspect, a system for initiating inclusions outwardly into a subterranean formation from a wellbore is described below. In one example, the system can include a casing section having multiple flow channels therein. Each of the flow channels is in communication with a respective one of multiple openings formed between adjacent pairs of circumferentially extendable longitudinally extending portions of the casing section.
In another aspect, a system for forming multiple inclusions into a subterranean formation can include a casing section, and an injection tool which engages the casing section and selectively directs fluid into each of the inclusions individually, whereby the inclusions are extended into the formation one at a time.
These and other features, advantages and benefits will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative examples below and the accompanying drawings, in which similar elements are indicated in the various figures using the same reference numbers.
Representatively illustrated in
In the system 10 as depicted in
Note that, in the
Preferably, the inclusions 12a,b are areas of increased permeability in the formation 14.
The formation 14 may be relatively unconsolidated, such that the formation yields and tears, rather than “fractures” when the inclusions 12a,b are propagated into the formation. Thus, the inclusions 12a,b may or may not comprise fractures, depending on the characteristics of the formation 14.
Although only two of the inclusions 12a,b and four of the openings 20a-d are visible in
As depicted in
This increase in the circumference of the casing section 16 causes cement 24 in an annulus 26 formed radially between the casing section and the wellbore 18 to part at each of the widening openings 20a-d. Thus, the initiation of the inclusions 12a,b preferably begins with the expansion of the casing section 16.
At this point, the inclusions 12a,b also preferably extend somewhat radially outward into the formation 14, due to dilation of the formation about the wellbore 18. Note that compressive stress in the formation 14 circumferentially about the wellbore 18 is preferably reduced, and compressive stress in the formation directed radial to the wellbore is increased, due to expansion of the casing section 16, thereby desirably influencing the inclusions 12a,b to propagate in a relatively consistent radial direction relative to the wellbore.
Note that the term “casing” as used herein indicates a protective wellbore lining. Casing can be comprised of tubular materials known to those skilled in the art as tubing, liner or casing. Casing can be segmented or continuous, installed in tubular form or formed in situ. Casing can be made of steel, other metals or alloys, plastics, composites or other materials. Casing can have conductors, optical waveguides or other types of lines interior to, external to or within a sidewall of the casing. Casing is not necessarily cemented in a wellbore.
Furthermore, note that the term “cement” as used herein indicates a hardenable material which supports an inner surface of a wellbore and, if the wellbore is cased, seals off an annulus formed radially between the wellbore and the casing, or between casings. Cement is not necessarily cementitious, since other types of materials (e.g., elastomers, epoxies, foamed materials, hardenable gels, etc.) can be used to support a wellbore or seal off an annulus.
Referring additionally now to
In the example depicted in
When the latch 30 is properly engaged with the latch profile 32, a tubular inflatable packer or bladder 34 is expanded radially outward into contact with the casing section 16. Increasing pressure applied to an interior of the bladder 34 will cause the casing section 16 to be biased radially outward, thereby widening the openings 20a-d and initiating the inclusions 12a,b.
Available pressure to inflate the bladder 34 and expand the casing section 16 can be provided by a pressure intensifier 40 in the expansion tool 28. In this example, the pressure intensifier 40 operates by alternately increasing and decreasing pressure in a tubular string 36 attached to the expansion tool 28 (and extending to a remote location, such as the earth's surface). However, other types of pressure intensifiers (e.g., which could respond to reciprocation or rotation of the tubular string 36, etc.) may be used, if desired.
The bladder 34 is preferably robust and capable of being inflated to about 10,000 psi (˜69 MPa) to radially outwardly expand the casing section 16. In the
The expansion tool 28 is described in further detail below in relation to
Referring additionally now to
In the example of
When the bladders 34a-c are inflated (e.g., by applying pressure to the tubular string 36 connected to the injection tool 42, etc.), the openings 20a-d are isolated from each other in the casing section 16. Fluid 46 can then be selectively discharged from each of multiple conduits 48a,b individually, to thereby propagate the inclusions 12a,b individually outward into the formation 14.
This individual control over flow of the fluid 46 into each inclusion 12a,b is beneficial, in part, because it allows an operator to control how each inclusion is formed, how far the inclusion extends into the formation 14, how quickly the fluid is flowed into each inclusion, etc. This, in turn, allows the operator to individually optimize the formation of each of the inclusions 12a,b.
In
Corresponding successively smaller diameter plugs (e.g., balls, darts, etc., not shown) are dropped into a flow passage 52 extending longitudinally through the tool 42. After each plug is dropped, the plug sealingly engages one of the seats 50a-d, and pressure is applied to the passage 52 (e.g., via the tubular string 36) to release a retainer (such as, a shear pin, snap ring, etc.) and allow the seat to displace and expose a port placing the passage above the plug in communication with the corresponding conduit 48a,b (and preventing communication between the passage and any conduit previously in communication with the passage). In this manner, each of the conduits 48a,b (a total of four of them in this example) is selectively and individually placed in communication with the passage 52 for flowing the fluid 46 into the inclusions 12a,b one at a time.
Referring additionally now to
In
In other examples, the openings 20a-f could be otherwise formed, could exist before or only after the casing section 16 is expanded, could be provided in an outer shell 56 of the casing section (e.g., instead of, or in addition to those in the inner shell 54), etc. Thus, any manner of forming the openings 20a-f may be used, in keeping with the scope of this disclosure.
Two bulkheads 58, 60 separate each adjacent pair of longitudinally extending portions 62a-f of the outer shell 56. Longitudinally extending flow channels 64a-f are, thus, defined radially between the respective inner and outer shell portions 44a-f and 62a-f, and circumferentially between the respective bulkheads 58, 60 to either circumferential side of the shell portions 44a-f and 62a-f.
The bulkheads may be sealed to each other (e.g., with sealant, small weld, etc.) to prevent fluid communication between the bulkheads during installation and cementing of the casing section 16, if desired.
Each of the bulkheads 60 has apertures 66 therein, permitting communication between the corresponding one of the channels 64a-f and the corresponding one of the openings 20a-f (at least in the expanded configuration). Thus, each of the channels 64a-f is in communication with a corresponding one of the openings 20a-f, and with a corresponding one of the inclusions 12a,b, at least in the expanded configuration of the casing section 16. In some examples, the channels 64a-f may continually be in communication with the respective openings 20a-f and/or inclusions 12a,b.
Preferably, the casing section 16 includes spacing limiters 68 which limit the widening of each opening 20a-f. The limiters 68 also preferably prevent subsequent narrowing of the openings 20a-f. However, use of the limiters 68 is not necessary in keeping with the principles of this disclosure.
Note that it is not necessary for the casing section 16 construction of
Referring additionally now to
As depicted in
Increased pressure can be applied to the piston 69 via the tubular string 36 (see
Fluid 72 can be pumped through check valves 74 via a chamber 76 exposed to the smaller piston diameter 69b. Note that the pressure intensifier 40 will need to be lowered relative to an outer housing assembly 78 after engaging the latch 30 with the profile 32, in order to align ports in the expansion tool 28 for flow of the fluid 72 from the tubular string 36 to the interior of the bladder 34. In
Thus, in operation, the expansion tool 28 is conveyed into the casing section 16 on the tubular string 36, and the latch 30 is engaged with the profile 32, thereby releasably securing the expansion tool in the casing section and positioning the bladder 34 in the longitudinal portions 44a-f, 62a-f of the casing section. The tubular string 36 is at this point lowered relative to the housing assembly 78, thereby lowering the pressure intensifier 40, and aligning the ports in the expansion tool, so that pressure applied to the tubular string is communicated to the interior of the bladder 34, thereby inflating the bladder. Pressure in the tubular string 36 can then be alternately increased and decreased, to thereby further increase the pressure applied to the interior of the bladder 34 via the pressure intensifier 40, and expand the casing section 16.
After expansion of the casing section 16, the tubular string 36 can be raised, thereby exposing the interior of the bladder 34 to the passage 80, and allowing the bladder to deflate. The latch 30 can be disengaged from the profile 32 by applying sufficient upward force to the expansion tool 28 via the tubular string 36, to retrieve the expansion tool.
Referring additionally now to
Rotating the tubular string 36 longitudinally displaces annular seals 82 which straddle ports 84 (see
Therefore, the tubular string 36 can be placed in communication with a selected one of the inclusions 12a,b for flowing the fluid 46 into the inclusion and propagating the inclusion further into the formation 14. Rotation of the tubular string 36 produces longitudinal displacement of the seals 82, due to threads 86 which unscrew from a mandrel 88 when the tubular string 36 is rotated.
The bladder 34 is inflated by applying pressure to the interior of the tubular string 36, thereby inflating the bladder. The bladder 34 can have a sealing material (such as an elastomer, etc.) on an outer surface thereof, so that the sealing material seals against the interior surface of the casing section 16.
In this manner, after the bladder 34 is inflated, the openings 20a-f are isolated from each other in the casing section 16. Thus, when the tubular string 36 is rotated to place the seals 82 straddling one of the ports 84, the fluid 46 flowed into the corresponding inclusion will not be communicated to any of the other inclusions. As a result, an individual inclusion 12a,b can be propagated into the formation 14, with individual control over how that inclusion is propagated.
In actual practice, the injection tool 42 is lowered into the well on the tubular string 36. The latch 30 is engaged with the profile 32 to secure the injection tool 42 relative to the casing section 16.
Pressure is then applied to the tubular string 36 to inflate the bladder 34 and isolate the openings 20a-f from each other. The tubular string 36 is then rotated to place the seals 82 straddling a first one of the ports 84 corresponding to a first one of the openings 20a-f. Fluid 46 is then pumped from the tubular string 36 to the port 84 between the seals 82, through the respective channel 64a-f, through the respective opening 20a-f, and then into the respective inclusion 12a,b.
When it is desired to flow the fluid 46 into another inclusion, the tubular string 36 is again rotated to place the seals 82 straddling another of the ports 84. In
The injection tool 42 examples of
Thus, fluid from multiple treated inclusions can be flowed through the injection tool 42. In one beneficial arrangement, multiple injection tools 42 can be installed in corresponding multiple casing sections 16, and certain azimuthal positions can be selected in each of the casing sections. For example, one injection tool 42 could be positioned to inject fluid into a certain inclusion, and another injection tool could be positioned to produce fluid from another chosen inclusion, with the two inclusions being in the same or different azimuthal orientations. Fluid could be simultaneously produced from one inclusion while fluid is injected into another inclusion in the same azimuthal orientation.
Although the examples as described above utilize the separate expansion tool 28 and injection tool 42, it will be appreciated that it is not necessary to perform the expansion and injection operations in separate trips into the wellbore 18. Instead, the expansion and injection tools 28, 42 could be incorporated into a same tool string to perform the expansion and injection steps in a single trip into the wellbore 18, the expansion and injection tools could be combined into a single tool assembly, etc.
The injection tool 42 may be used to re-treat the inclusions 12a,b at a later date (e.g., after the inclusions are initially propagated into the formation 14).
The injection tool 42 can be used to treat any combination of inclusions 12 at any azimuthal orientations relative to the casing section 16 simultaneously, or individually, and in any order. For example, inclusions 12 at azimuthal orientations of 0, 120, 240, 60, 180 and 300 degrees (or at another order of azimuthal orientations of 0, 180, 60, 240, 120 and 300 degrees) could be treated. It is not necessary for the azimuthal orientations to be equally spaced apart, or for there to be any particular number of azimuthal orientations.
It may now be fully appreciated that the disclosure above provides several advancements to the art of forming inclusions into a formation. In some examples described above, the inclusions 12a,b can be individually propagated into the formation 14, thereby allowing enhanced control over how the inclusions are formed, etc.
In one aspect, this disclosure describes a method of forming multiple inclusions 12a,b into a subterranean formation 14. In one example, the method can include initiating the inclusions 12a,b into the formation 14, the inclusions 12a,b extending outwardly in respective multiple azimuthal orientations from a casing section 16; and flowing fluid 46 into each of the inclusions 12a,b individually, thereby extending the inclusions 12a,b into the formation 14 one at a time.
The inclusion initiating can include simultaneously initiating multiple inclusions 12a,b.
The inclusion initiating can include circumferentially enlarging the casing section 16. The casing section 16 may be circumferentially enlarged in response to inflating an inflatable bladder 34 within the casing section 16. Circumferentially enlarging the casing section 16 can include widening openings 20a-f formed through the casing section 16, the openings 20a-f being in communication with the inclusions 12a,b.
Inflating the bladder 34 may include applying pressure to a pressure intensifier 40 in communication with the bladder 34.
Flowing the fluid 46 can include flowing the fluid 46 through channels 64a-f formed longitudinally through the casing section 16. Each channel 64a-f may correspond to a respective one of the inclusions 12a,b and/or to a respective one of multiple longitudinally extending openings 20a-f formed through a side wall of the casing section 16. The inclusions 12a,b may be initiated in response to widening the openings 20a-f. The channels 64a-f may be disposed radially between inner and outer shells 54, 56 of the casing section 16.
Initiating the inclusions 12a,b can include widening multiple openings 20a-f formed through a side wall of the casing section 16. Flowing the fluid 46 can include isolating the openings 20a-f from each other while fluid 46 is flowed into each inclusion 12a,b.
Isolating the openings 20a-f may include inflating a bladder 34 in the casing section 16. Isolating the openings 20a-f can include inflating multiple longitudinally extending bladders 34a-c, each bladder 34a-c being positioned between an adjacent pair of the openings 20a-d.
A system for initiating inclusions outwardly into a subterranean formation from a wellbore is also described above. In one example, the system 10 can include a casing section 16 having multiple flow channels 64a-f therein, each of the flow channels 64a-f being in communication with a respective one of multiple openings 20a-f formed between adjacent pairs of circumferentially extendable longitudinally extending portions 44a-f, 62a-f of the casing section 16.
The casing section 16 can also include inner and outer shells 54, 56, with the flow channels 64a-f being disposed radially between the inner and outer shells 54, 56.
The system 10 may include longitudinally extending bulkheads 58, 60 which straddle each of the openings 20a-f, each channel 64a-f being in communication with the respective one of the openings 20a-f via a respective one of the bulkheads 60.
The system 10 can include an inflatable bladder 34 which expands the casing section 16 in response to the bladder 34 being inflated. The system 10 can include multiple longitudinally extending bladders 34a-c, each of the bladders 34a-c being positioned between an adjacent pair of the openings 20a-d.
The system 10 can include an inflatable bladder 34 which isolates the openings 20a-f from each other in the casing section 16.
The system 10 can include an injection tool 42 which provides selective communication with individual ones of the flow channels 64a-f. The injection tool 42 may selectively isolate each of multiple ports 84 formed in the casing section 16, each of the ports 84 being in communication with a respective one of the flow channels 64a-f.
Also described above, in one example, is a system 10 for forming multiple inclusions 12a,b into a subterranean formation 14 from a wellbore 18. The system 10 in this example can include one or more casing sections 16 and one or more injection tools 42 which engage the casing section 16 and selectively direct fluid 46 into each of the inclusions 12a,b individually, whereby the inclusions 12a,b are extended into the formation 14 one at a time.
The casing section 16, when circumferentially extended, can initiate the inclusions 12a,b into the formation 14, whereby the inclusions 12a,b extend outwardly in respective multiple azimuthal orientations from the casing section 16.
The system 10 can include an expansion tool 28 which expands the casing section 16 and thereby simultaneously initiates multiple inclusions 12a,b. In other examples, multiple inclusions 12a,b may not be simultaneously initiated.
The expansion tool 28 may comprise an inflatable bladder 34. The expansion tool 28 may further comprise a pressure intensifier 40 in communication with the bladder 34.
Openings 20a-f in communication with the inclusions 12a,b can be widened in response to expansion of the casing section 16.
The casing section 16 may include channels 64a-f formed longitudinally through the casing section 16. Each channel 64a-f can correspond to a respective one of the inclusions 12a,b. Each channel 64a-f can correspond to a respective one of multiple longitudinally extending openings 20a-f formed through a side wall of the casing section 16. The inclusions 12a,b may be initiated in response to the openings 20a-f being widened.
The channels 64a-f may be disposed radially between inner and outer shells 54, 56 of the casing section 16.
The inclusions 12a,b may be initiated in response to multiple openings 20a-f formed through a side wall of the casing section 16 being widened. The openings 20a-f can be isolated from each other while fluid 46 is flowed into each inclusion 12a,b.
The openings 20a-f can be isolated from each other by a bladder 34 inflated in the casing section 16. The openings 20a-f can be isolated from each other by multiple longitudinally extending bladders 34a-c, each bladder 34a-c being positioned between an adjacent pair of the openings 20a-f.
The at least one casing section 16 may comprise multiple casing sections 16. The at least one injection tool 42 may comprise multiple injection tools 42. A first injection tool 42 can selectively direct fluid into a first inclusion 12, and a second injection tool 42 can selectively produce fluid from a second inclusion 12. The first and second inclusions 12 may be in a same azimuthal orientation. The first injection tool 42 may direct fluid into the first inclusion 12 concurrently as the second injection tool 42 produces fluid from the second inclusion 12.
It is to be understood that the various examples described above may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of this disclosure. The embodiments illustrated in the drawings are depicted and described merely as examples of useful applications of the principles of the disclosure, which are not limited to any specific details of these embodiments.
In the above description of the representative examples, directional terms (such as “above,” “below,” “upper,” “lower,” etc.) are used for convenience in referring to the accompanying drawings. However, it should be clearly understood that the scope of this disclosure is not limited to any particular directions described herein.
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are within the scope of the principles of this disclosure. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the invention being limited solely by the appended claims and their equivalents.
Number | Date | Country | Kind |
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PCT/US11/53403 | Sep 2011 | US | national |
This application claims the benefit under 35 USC §119 of the filing date of International Application Serial No. PCT/US11/53403, filed 27 Sep. 2011. The entire disclosure of this prior application is incorporated herein by this reference.