This disclosure relates generally to equipment and operations utilized in conjunction with subterranean wells and, in an example described below, more particularly provides a downhole valve, and associated systems and methods.
Valves operable downhole can be used in gravel packing operations in wells. Although variations are possible, a gravel pack is generally an accumulation of “gravel” (typically sand, proppant or another granular or particulate material, whether naturally occurring or synthetic) about a tubular filter or screen in a wellbore. The gravel is sized, so that it will not pass through the screen, and so that sand, debris and fines from an earth formation penetrated by the wellbore will not easily pass through the gravel pack with fluid flowing from the formation. Although relatively uncommon, a gravel pack may also be used in an injection well, for example, to support an unconsolidated formation.
Placing the gravel about the screen in the wellbore is a complicated process, requiring relatively sophisticated equipment and techniques to maintain well integrity while ensuring the gravel is properly placed in a manner that provides for subsequent efficient and trouble-free operation. It will, therefore, be readily appreciated that improvements are continually needed in the arts of designing and utilizing gravel pack equipment and methods. Such improved equipment and methods may be useful with any type of gravel pack in cased or open wellbores, and in vertical, horizontal or deviated well sections.
The improved equipment and methods may also be used in other types of well operations. For example, drilling, fracturing, conformance, steam flooding, disposal and other operations could utilize concepts described more fully below.
Representatively illustrated in
In the
Setting the packer 20 in the wellbore 12 provides for isolation of an upper well annulus 22 from a lower well annulus 24 (although, as described above, at the time the packer is set, the upper annulus and lower annulus may be in communication with each other). The upper annulus 22 is formed radially between the service string 18 and the wellbore 12, and the lower annulus 24 is formed radially between the completion assembly 16 and the wellbore.
The terms “upper” and “lower” are used herein for convenience in describing the relative orientations of the annulus 22 and annulus 24 as they are depicted in
As depicted in
In the
Examples of some steps of the method are representatively depicted in
Referring now to
Note that, as shown in
As depicted in
This increased pressure operates a packer setting tool 36 of the service string 18. The setting tool 36 can be of the type well known to those skilled in the art, and so further details of the setting tool and its operation are not illustrated in the drawings or described herein.
Although the packer 20 in this example is set by application of increased pressure to the setting tool 36 of the service string 18, in other examples the packer may be set using other techniques. For example, the packer 20 could be set by manipulation of the service string 18 (e.g., rotating in a selected direction and then setting down or pulling up, etc.), with or without application of increased pressure. Thus, the scope of this disclosure is not limited to any particular technique for setting the packer 20.
Note that, although the set packer 20 separates the upper annulus 22 from the lower annulus 24, in the step of the method as depicted in
In
An annular seal 44 is sealingly received in a seal bore 46. The seal bore 46 is located within the packer 20 in this example, but in other examples, the seal bore could be otherwise located (e.g., above or below the packer).
In the step as depicted in
An upper end of the flow passage 38 is in communication with the upper annulus 22 via an upper port 54. Although not clearly visible in
Thus, it will be appreciated that the flow passage 38 and ports 40, 54 effectively bypass the seal bore 46 (which is engaged by the annular seals 44, 52 carried on the service string 18) and allow for hydrostatic pressure in the upper annulus 22 to be communicated to the lower annulus 24. This enhances wellbore 12 stability, in part by preventing pressure in the lower annulus 24 from decreasing (e.g., toward pressure in the formation 14) when the packer 20 is set.
As depicted in
However, the flow passage 32 is now in communication with the lower annulus 24 via the openings 42 and one or more ports 58 in the service string 18. Thus, hydrostatic pressure continues to be communicated to the lower annulus 24. The valve assembly 80 remains in its open configuration.
The lower annulus 24 is isolated from the upper annulus 22 by the packer 20. The flow passage 38 is not in communication with the lower annulus 24 due to the annular seal 56 in the seal bore 46. The flow passage 50 may be in communication with the lower annulus 24, but no flow is permitted through the port 48 due to the annular seal 52 in the seal bore 46. Thus, the lower annulus 24 is isolated completely from the upper annulus 22.
In the
As depicted in
Thus, in this example, the reversing valve 60 is an annular pressure-operated sliding sleeve valve of the type well known to those skilled in the art, and so operation and construction of the reversing valve is not described or illustrated in more detail by this disclosure. However, it should be clearly understood that the scope of this disclosure is not limited to use of any particular type of reversing valve, or to any particular technique for operating a reversing valve.
The raising of the service string 18 relative to the completion assembly 16 can facilitate operations other than opening of the reversing valve 60. In this example, the raising of the service string 18 can function to prepare a valve assembly 80 connected in or below a washpipe 62 of the service string for closing, as described more fully below. The valve assembly 80 can (when closed) substantially or completely prevent flow from the flow passage 32 into an interior of the well screen 26.
In the
A gravel slurry 64 (a mixture of the gravel 28 and one or more fluids 66) can now be flowed from surface through the flow passage 32 of the service string 18, and outward into the lower annulus 24 via the openings 42 and ports 58. The fluids 66 can flow inward through the well screen 26, into the washpipe 62, and to the upper annulus 22 via the flow passage 50 for return to surface. In this manner, the gravel 28 is deposited into the lower annulus 24 (see
As depicted in
A clean fluid 68 can now be circulated from surface via the upper annulus 22 and inward through the open reversing valve 60, and then back to surface via the flow passage 32. This reverse circulating flow can be used to remove any gravel 28 remaining in the flow passage 32 after the gravel slurry 64 pumping operation.
After reverse circulating, the service string 18 can be conveniently retrieved to surface and a production tubing string (not shown) can be installed. Flow through the openings 42 is prevented when the service string 18 is withdrawn from the completion assembly 16 (e.g., by shifting a sleeve of the type known to those skilled in the art as a closing sleeve). A lower end of the production tubing string can be equipped with annular seals and stabbed into the seal bore 46, after which fluids can be produced from the formation 14 through the gravel 28, then into the well screen 26 and to surface via the production tubing string.
An optional treatment step is depicted in
As depicted in
The lower portion of the flow passage 50 is, thus, now isolated from the upper annulus 22. However, the lower portion of the flow passage 50 now provides for communication between the flow passage 32 and the interior of the well screen 26 via the washpipe 62. Note, also, that the lower annulus 24 is isolated from the upper annulus 22.
A treatment fluid 76 can now be flowed from surface via the flow passages 32, 50 and washpipe 62 to the interior of the well screen 26, and thence outward through the well screen into the gravel 28. If desired, the treatment fluid 76 can further be flowed into the formation 14.
The treatment fluid 76 could be any type of fluid suitable for treating the well screen 26, gravel 28, wellbore 12 and/or formation 14. For example, the treatment fluid 76 could comprise an acid for dissolving a mud cake (not shown) on a wall of the wellbore 12, or for dissolving contaminants deposited on the well screen 26 or in the gravel 28. Acid may be flowed into the formation 14 for increasing its permeability. Conformance agents may be flowed into the formation 14 for modifying its wettability or other characteristics. Breakers may be flowed into the formation 14 for breaking down gels used in a previous fracturing operation. Thus, it will be appreciated that the scope of this disclosure is not limited to use of any particular treatment fluid, or to any particular purpose for flowing treatment fluid into the completion assembly 16.
As depicted in
Although only a single packer 20, well screen 26 and gravel packing operation is described above for the
Referring additionally now to
As depicted in
In the
Sealingly and reciprocably received in the housing 82 is a generally tubular mandrel 86. Seals 88 carried on the mandrel 86 prevent fluid communication through a longitudinally extending slot 90 formed through the housing 82.
At an upper end (as viewed in
Another generally tubular extension 94 is formed on the mandrel 86 at a lower end thereof (as viewed in
The biasing device 100 exerts an upwardly directed (as viewed in
The biasing device 100 is depicted in
The flapper valve 96 includes a closure or flapper 102 pivotably secured relative to a seat 104. The seat 104 is received in an upper end of the housing 82, and is configured for sealing engagement with the flapper 102 when the flapper valve 96 is closed (see
As depicted in
Reciprocably disposed on the housing 82 is an engagement device 106 including a circumferentially distributed set of engagement members or keys 108. The keys 108 are configured for releasable engagement with one or more internal profiles in an outer tubular string (such as the completion assembly 16). The keys 108 in this example are biased radially outward (for example, using leaf springs, not visible in
A pin 110 is secured to the engagement device 106, extends through the slot 90, and is secured to the mandrel 86. In this manner, the mandrel 86 and the engagement device 106 can reciprocably displace together relative to the housing 82. Engagement of the pin 110 in the slot 90 also prevents rotation of the engagement device 106 relative to the housing 82.
A pin-shaped follower 112 protrudes inwardly from an annular rotary bearing 114. The bearing 114 permits the follower 112 to rotate about the housing 82 in a case 116 of the engagement device 106.
The follower 112 is received in a profile 118 formed on the housing 82. The profile 118 is of the type known to those skilled in the art as a “ratchet” or “J-slot” profile. As described more fully below, when the engagement device 106 displaces longitudinally relative to the housing 82, the follower 112 traverses a succession of different sections of the profile 118, thereby controlling an extent of the longitudinal displacement to be changed.
In other examples, the follower 112 could be rigidly secured to the housing 82 and the profile 118 could be carried by the bearing 114. In further examples, the profile 118 could be in the form of a raised track, instead of a recessed slot, and the follower 112 could be a “female” rather than a “male” member. Thus, it will be appreciated that the scope of this disclosure is not limited to any particular details of the engagement device 106 or any of its components.
As depicted in
In this configuration, the valve assembly 80 can be displaced through a tubular string (such as the completion assembly 16) in a downward direction. If the tubular string includes one or more internal profiles engageable by the keys 108, the keys may momentarily engage the profile(s), but the keys will disengage from the profile(s) as soon as a sufficient downward force is applied to cause the keys to retract (due to mating surfaces on the keys 108 and the internal profiles being angled somewhat). Thus, downward displacement of the valve assembly 80 will not cause actuation of the valve assembly between its open and closed configurations.
Referring additionally now to
The tubular string 120 includes a coupling 122 having an internal radially inwardly extending shoulder or profile 124 formed therein. The profile 124 is complementarily shaped relative to a recessed profile 126 on each of the keys 108.
As depicted in
The keys 108 will remain in engagement with the profile 124 until a sufficient upward or downward force is applied to the valve assembly 80 to cause the keys to retract (due to mating surfaces on the keys 108 and the internal profile 124 being angled somewhat). Preferably, the biasing force exerted by the biasing device 100 is at no point greater than this force needed to retract the keys 108 out of engagement with the profile 124.
Note that, in the
As described above, the valve assembly 80 can displace downwardly through the tubular string 120 and traverse one or more profiles 124, without causing actuation of the valve assembly between its open and closed configurations. However, as the valve assembly 80 is displaced upwardly through the tubular string 120, the keys 108 will engage a profile 124, the engagement device 106 and mandrel 86 will cease displacing relative to the tubular string, the biasing device 100 will be compressed, and then the keys will disengage from the profile 124 when a sufficient upward force is applied to the valve assembly (due to mating surfaces on the keys 108 and the internal profile 124 being angled somewhat).
Referring additionally now to
However, note that the engagement device 106 and mandrel 86 are not displaced upward to their
In the
Thus, in the closed configuration, the flapper valve 96 functions as a check valve, permitting relatively unrestricted flow in only one direction through the passage 98. In the example of
The valve assembly 80 in the closed configuration of
The valve assembly 80 can be returned to its
As the valve assembly 80 in its closed configuration is displaced upwardly through the tubular string 120, the keys 108 engage will the profile 124, the engagement device 106 and mandrel 86 will cease displacing relative to the tubular string, the biasing device 100 will be compressed, and then the keys will disengage from the profile 124 when a sufficient upward force is applied to the valve assembly. The biasing force exerted by the biasing device 100 will then displace the engagement device 106 and the mandrel 86 upward relative to the housing 82 and the flapper valve 96, thereby returning the valve assembly 80 to its
Referring additionally now to
The position 112a corresponds to the open configuration of
The position 112b corresponds to the partially actuated configuration of
The position 112c corresponds to the closed configuration of
With the profile 118 of
In
In the
The engagement device 106, biasing device 100 and profile 118 of the valve assembly 80 could be inverted from their
In another example, the entire valve assembly 80 could be inverted from its
Referring additionally now to
As depicted in
It may now be fully appreciated that the above disclosure provides significant advancements to the arts of constructing and operating downhole valves. In examples described above, the valve assembly 80 can provide for enhanced convenience and reliable operation in gravel packing and other well operations.
The above disclosure provides to the art a valve assembly 80 for use in a subterranean well. In one example, the valve assembly 80 can include a generally tubular housing 82, a mandrel 86 reciprocably disposed in the housing 82 and operative to displace a valve closure 102 in response to relative displacement between the mandrel 86 and the housing 82, an engagement device 106 reciprocably disposed externally on the housing 82 and secured relative to the mandrel 86, whereby the mandrel displaces with the engagement device, and a biasing device 100 that biases the mandrel 86 and engagement device 106 in a selected longitudinal direction.
A limit of longitudinal displacement of the engagement device 106 relative to the housing 82 in the longitudinal direction may vary in response to a change in position of a follower 112 relative to a profile 118. The follower 112 may rotate about the housing 82. The profile 118 may be formed on the housing 82.
The valve closure 102 can comprise a flapper. The mandrel 86 may contact the flapper and pivot the flapper away from a seat 104 in response to displacement of the mandrel 86 in the longitudinal direction.
The engagement device 106 may include at least one engagement member 108 that engages a profile 124 in a tubular string 120 external to the valve assembly 80. In response, the engagement device 106 ceases to displace relative to the profile 124 and the housing 82 displaces in the longitudinal direction relative to the engagement device 106.
The valve assembly 80 may be actuated to an open configuration in response to displacement of the valve assembly in the longitudinal direction through a tubular string 120 external to the valve assembly. The valve assembly 80 may be actuated to a closed configuration in response to displacement of the valve assembly in the longitudinal direction through the tubular string 120.
A system 10 for use in a subterranean well is also provided to the art by the above disclosure. In one example, the system 10 can include a tubular string 120 and a valve assembly 80 reciprocably disposed in the tubular string. The valve assembly 80 includes a valve 96 that selectively restricts flow through a passage 98 formed longitudinally through the valve assembly. The valve 96 closes in response to displacement of the valve assembly 80 in a selected longitudinal direction relative to the tubular string 120, and the valve 96 opens in response to displacement of the valve assembly 80 in the same longitudinal direction relative to the tubular string 120.
The tubular string 120 may include at least one internal profile 124. The valve 96 closes further in response to displacement of a housing 82 of the valve assembly 80 relative to the internal profile 124, and the valve 96 opens further in response to displacement of the housing 82 relative to the internal profile 124.
The valve assembly 80 may include a mandrel 86 reciprocably disposed in the housing 82, and a biasing device 100 that biases the mandrel in the longitudinal direction relative to the housing.
The valve assembly 80 may include a profile 118 and a follower 112. A position of a mandrel 86 relative to the valve 96 is determined by a position of the follower 112 relative to the profile 118.
The mandrel 86 may contact and displace a closure 102 of the valve 96 to an open position in response to displacement of the follower 112 to one position relative to the profile 118. The mandrel 86 may disengage from the closure 102 and allow the closure 102 to displace to a closed position in response to displacement of the follower 112 to a second position relative to the profile 118.
The valve assembly 80 may include a housing 82 and an engagement device 106 that engages an internal profile 124 in the tubular string 120. The valve 96 closes in response to displacement of the engagement device 106 in the longitudinal direction relative to the housing 82, and the valve 96 opens in response to displacement of the engagement device 106 in the same longitudinal direction relative to the housing 82.
The valve assembly 80 may include a biasing device 100. The biasing device 100 displaces the engagement device 106 in the longitudinal direction relative to the housing 82 in response to disengagement of the engagement device from the internal profile 124.
A method of gravel packing a well is also described above. In one example, the method comprises: displacing a service string 18 in a selected longitudinal direction within a completion assembly 16, the service string 18 including a valve assembly 80 that selectively restricts flow through a longitudinal flow passage 32 of the service string; opening the valve assembly 80 as the valve assembly displaces in the longitudinal direction; and closing the valve assembly 80 as the valve assembly displaces in the same longitudinal direction.
The displacing step may include compressing a biasing device 100 in response to engagement between an engagement device 106 of the valve assembly 80 and an internal profile 124 in the completion assembly 16.
The opening step may include the biasing device 100 elongating in response to disengagement between the engagement device 106 and the internal profile 124. The closing step may also include the biasing device 100 elongating in response to disengagement between the engagement device 106 and the internal profile 124.
The opening step may include the engagement device 106 displacing in the longitudinal direction relative to a housing 82 of the valve assembly 80. The closing step may include the engagement device 106 displacing in the same longitudinal direction relative to the housing 82.
Although various examples have been described above, with each example having certain features, it should be understood that it is not necessary for a particular feature of one example to be used exclusively with that example. Instead, any of the features described above and/or depicted in the drawings can be combined with any of the examples, in addition to or in substitution for any of the other features of those examples. One example's features are not mutually exclusive to another example's features. Instead, the scope of this disclosure encompasses any combination of any of the features.
Although each example described above includes a certain combination of features, it should be understood that it is not necessary for all features of an example to be used. Instead, any of the features described above can be used, without any other particular feature or features also being used.
It should be understood that the various embodiments described herein 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 are described merely as examples of useful applications of the principles of the disclosure, which is 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.
The terms “including,” “includes,” “comprising,” “comprises,” and similar terms are used in a non-limiting sense in this specification. For example, if a system, method, apparatus, device, etc., is described as “including” a certain feature or element, the system, method, apparatus, device, etc., can include that feature or element, and can also include other features or elements. Similarly, the term “comprises” is considered to mean “comprises, but is not limited to.”
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the disclosure, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to the specific embodiments, and such changes are contemplated by the principles of this disclosure. For example, structures disclosed as being separately formed can, in other examples, be integrally formed and vice versa. 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.