The invention relates to a wellbore tool with an indexing mechanism and methods using the tool.
If a wellbore tool is positioned down hole in advance of its required operation, the tool must be actuated remotely. Indexing mechanisms may be useful where a tool is intended to be actuated through a number of positions.
For example, in some tools, indexing mechanisms are employed to actuate a tool through a number of inactive positions before it reaches an active position. For example, indexing mechanisms may be employed in wellbore tools for wellbore fluid treatment such as staged well treatment. In staged well treatment, a wellbore treatment string is deployed to create a plurality of isolated zones within a well and includes a plurality of openable ports that allow selected access to each such isolated zone. The treatment string is based on a tubing string and carries a plurality of packers that can be set in the hole to create isolated zones therebetween about the annulus of the tubing string. Between at least selected packers, there are openable ports through the tubing string. The ports are selectively openable and include a sleeve thereover with a sealable seat formed in the inner diameter of the sleeve. By launching a ball, the ball can seal against the seat and pressure can be increased behind the ball to drive the sleeve through the tubing string to open the port in one zone. The seat in each sleeve can be formed to accept a ball of a selected diameter but to allow balls of lower diameters to pass.
Unfortunately, due to size limitations with respect to the inner diameter of wellbore tubulars (i.e. due to the inner diameter of the well), such wellbore treatment systems may tend to be limited in the number of zones that may be accessed. For example, if the well diameter dictates that the largest sleeve in a well can at most accept a 3¾ ball, then the well treatment string will generally be limited to approximately eleven sleeves and, therefore, can treat in only eleven stages.
In accordance with an aspect of the present invention, there is provided a wellbore tool comprising: a tubular housing including an upper end, a lower end, and a wall defining an inner bore and an outer surface; a tool mechanism capable of being moved through a plurality of positions; an indexing mechanism for moving the tool mechanism through the plurality of positions, the indexing mechanism including an axis, a first ratchet sleeve including a first plurality of teeth extending substantially parallel to the axis and a notch between each adjacent pair of teeth of the first plurality of teeth, a dog sleeve including an end and a dog extending axially from the end, the dog configured for meshing with the first plurality of teeth of the ratchet sleeve, the dog sleeve and/or the ratchet sleeve being axially and rotationally moveable to permit the dog and the first plurality of teeth to move into and out of engagement and to permit the dog to move from notch to notch along the first ratchet sleeve, the movement from notch to notch corresponding to movement of the tool mechanism through the plurality of positions; a biasing member for urging the dog and the first plurality of teeth into one of (i) meshing engagement or (ii) out of meshing engagement, the biasing member able to be overcome to allow movement of the dog and the first plurality of teeth axially into the other of (i) meshing engagement or (ii) out of meshing engagement; and an actuating mechanism for generating an application of force to overcome the biasing member.
In accordance with another aspect of the present invention, there is provided a wellbore fluid treatment string for installation in a wellbore, the wellbore fluid treatment string comprising: a sliding sleeve sub including: a tubular housing including an upper end, a lower end and a wall defining an inner bore and an outer surface; a fluid port through the wall of the tubular housing; and a sleeve installed in the inner bore, the sleeve being axially slidable in the inner bore at least from a first position covering the fluid port to a second position exposing the fluid port to the inner bore; a first ratchet sleeve including a first plurality of teeth extending substantially parallel to the axis and a notch between each adjacent pair of teeth of the first plurality of teeth and a final notch after the plurality of teeth; a dog sleeve including a dog extending axially from an end thereof for meshing with the first plurality of teeth, the dog sleeve and/or the ratchet sleeve being axially and rotationally moveable to permit the dog and the first plurality of teeth to move into and out of engagement and to permit the dog to move from notch to notch along the first ratchet sleeve until the dog lands in the final notch; a biasing member for urging the dog and the first plurality of teeth into one of (i) meshing engagement or (ii) out of meshing engagement, the biasing member able to be overcome to allow movement of the dog and the first plurality of teeth axially into the other of (i) meshing engagement or (ii) out of meshing engagement; an actuating mechanism for generating an application of force to act against the biasing member; and wherein the sleeve is moveable from the first position to the second position only after the dog lands in the final notch.
In accordance with another aspect of the present invention, there is provided a method for actuating a downhole tool to an active condition, the method comprising: axially moving a component of an indexing mechanism to move a dog in the downhole tool into and out of meshing engagement with a crown ratchet sleeve, the dog being moved from a first notch to a next notch in the indexing mechanism until the dog reaches a final notch in the indexing mechanism, the tool being configured into an active condition when the dog reaches the final notch.
It is to be understood that other aspects of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein various embodiments of the invention are shown and described by way of illustration. As will be realized, the invention is capable for other and different embodiments and its several details are capable of modification in various other respects, all without departing from the spirit and scope of the present invention. Accordingly the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.
Referring to the drawings, several aspects of the present invention are illustrated by way of example, and not by way of limitation, in detail in the figures, wherein:
The description that follows and the embodiments described therein, are provided by way of illustration of an example, or examples, of particular embodiments of the principles of various aspects of the present invention. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the invention in its various aspects. In the description, similar parts are marked throughout the specification and the drawings with the same respective reference numerals. The drawings are not necessarily to scale and in some instances proportions may have been exaggerated in order more clearly to depict certain features,
A wellbore tool that is actuable through a plurality of positions may include a tubular housing including an upper end, a lower end, an inner bore and an outer surface; a tool mechanism capable of being moved through a plurality of positions; an indexing mechanism for moving the tool mechanism through the plurality of positions, the indexing mechanism including an axis, a first ratchet sleeve including a first plurality of teeth extending substantially parallel to the axis and a notch between each adjacent pair of teeth of the first plurality of teeth; a dog sleeve including a dog extending axially from an end thereof for meshing with the first plurality of teeth of the ratchet sleeve, the dog sleeve and/or the ratchet sleeve being axially and rotationally moveable to permit the dog and the first plurality of teeth to move into engagement and to permit the dog to move from notch to notch along the first ratchet sleeve; and a biasing member for urging the dog and the first plurality of teeth into one axial position, the biasing member able to be overcome to allow movement of the dog and the first plurality of teeth axially into a second position to permit the dog and the first plurality of teeth to alternate into and out of meshing engagement; and an actuating mechanism for generating an application of force to act against the biasing member.
In operation, the tool may be employed in a wellbore operation wherein the tool is positioned in a well with the housing in a selected position, a force may be applied to an indexing mechanism of the tool to drive a tool mechanism through a plurality of positions, the applied force driving a dog and a plurality of ratchet teeth axially out of engagement and causing a slight relative rotation between the dog and the plurality of ratchet teeth and biasing the dog and the plurality of teeth back into engagement to move the dog from a first position relative to the plurality of teeth to a second position which is slightly rotated from the first position.
Generally, a wellbore tool often has a tubular housing, as a tubular form can pass readily through the wellbore as drilled. Also, tubular forms can be connected by threading into assembled tools or strings deployable into a well. The tool may be run into a well for temporary use or may be installed in a well for longer term use or reuse.
The wellbore tool may be a packer, an anchor, a sliding sleeve tool, etc. The form of the wellbore tool is determined by its tool mechanism. For example, a packer includes a tool mechanism including packing mechanism with at least a set and an unset position, the packing mechanism may include an annular packing element, a compression ring, etc. The tool mechanism of an anchor includes an anchoring mechanism including at least a set and an unset position, the anchoring mechanism may include a plurality of slips, a slip expander, etc. A tool mechanism of a sliding sleeve tool includes a port and a sliding sleeve moveable to open and close the port and the sliding sleeve tool has at least a closed port position and an open port position. As another example, another sliding sleeve tool has a tool mechanism including a port, a sliding sleeve moveable to open and close the port and a seat for the sliding sleeve to allow ball actuation of the sliding sleeve and in such an embodiment, the sliding sleeve valve may include at least an activated seat position ready to catch a ball (or other plug that is sized to seal in the seat) and an inactive seat position wherein either the seat has not yet formed or the seat is in place but the ball may pass through the seat.
The form of the tool determines the method that is carried out by the tool. For example, the method may include forming an annular seal, anchoring a tool, opening a port or forming a seat.
The tools and methods of the present invention can be used in various borehole conditions including open holes, cased holes, vertical holes, horizontal holes, straight holes or deviated holes.
With reference to
In the drawings,
The illustrated sliding sleeve tool includes a tubular housing 20 including an upper end 20a, a lower end 20b, an inner bore 20c and an outer surface 20d. The sliding sleeve tool, may be formed as a sub with its tubular housing 20 having threaded ends such that it may be connected into a wellbore tubular string. The housing defines a long axis x extending through its ends 20a, 20b.
The sliding sleeve tool includes one or more ports 22 through the wall of the tubular housing where the port, when opened, provides access between inner bore 20c and outer surface 20d. The open and closed condition of port 22 is determined by sleeve 12. The sleeve is axially moveable in the tubular housing between a position overlying and closing port 22 (
The sleeve includes seat 16 that is capable of being configured through a plurality of positions including a plurality of inactive positions and an active position. In the inactive positions (
The indexing mechanism is operable to control the movement of the tool mechanism through the plurality of positions. In the illustrated embodiment, the indexing mechanism is substantially coaxial with axis x. The indexing mechanism includes an end of sleeve 12 formed to act as a first ratchet sleeve 12a and includes a first plurality of teeth 28 extending substantially parallel to the axis and a notch 29 between each adjacent pair of teeth of the first plurality of teeth and a notch 29′ after the last tooth of the first plurality of teeth. The first plurality of teeth 28 are positioned at the end of the sleeve and the teeth extend axially from the end of sleeve 12 with the notches 29 exposed. At least a portion of the base of each tooth 28, where the tooth extends from sleeve 12, is axially in line with both the flanks 28a, 28b of the tooth and the sleeve, such that any force substantially parallel to axis x that is applied against the flanks can pass axially through the tooth, through its base and into sleeve. The teeth and the notches alternate in a direction about the circumference of the sleeve such that the end of the sleeve 12 has a saw tooth effect. As such, the first ratchet sleeve may be termed a crown-type ratchet sleeve.
Each tooth of the plurality of teeth include a steeply sloped front flank 28a and a moderately sloped rear flank 28b, causing the notches 29 to each be generally V-shaped.
The first ratchet sleeve may include any number of teeth to form any number of notches 29, 29′. The number of notches may be selected to be at least equal to the number of positions through which the indexing mechanism is intended to move in operation. For example, notches 29, 29′ may be formed about the entire circumference of the end of the sleeve and, as such, depending on the size of each notch and the diameter of the sleeve, there may be a great number of notches. On the other hand if it is desired to index the tool through only a few positions, then only a few notches need be formed. In one embodiment, for example, the indexing mechanism is formed with a number of notches, for example fifteen, selected to be the maximum number of possible indexing positions the tool is to have, which allows the tool to be set up to have any number of indexing positions up to fifteen.
All teeth/notches may be similarly formed or there may be differing forms depending on the intended operation of the indexing mechanism. As will be better appreciated from the following description, the presently illustrated indexing mechanism is intended to impart a final axial shift in the tool, when the indexing mechanism reaches its final position, thus the notches may have differing depths, and in this embodiment, for example, the final notch 29′ is positioned at the end of the plurality of teeth and has a depth that it penetrates axially into the end of the greater than the depth of other notches 29.
The indexing mechanism further includes a dog sleeve 30 including a dog 32 extending axially from an end thereof. In the illustrated embodiment, dog 32 is positioned at the end of dog sleeve 30 and extends fully beyond the end of ratchet sleeve 12a such that its side edges 32a, 32b are fully, axially exposed. At least a portion of the base of dog 32, where the dog extends from sleeve 30, is axially in line with side edges 32a, 32b of the tooth and with the sleeve, such that any force parallel to axis x against the flanks can pass axially through the dog, through its base and into sleeve 30. In the tool, dog sleeve 30 is installed such that dog 32 extends toward teeth 28 of sleeve 12a. Dog 32 is sized and shaped to mesh with the first plurality of teeth of the ratchet sleeve 12a. For example, dog 32 is sized and shaped to fit into the notches 29, 29′ formed by the teeth. One, as shown, or both side edges 32a, 32b are sloped toward the outboard tip 32c of the dog such that the outboard end of the dog is wedge shaped. In the illustrated embodiment, dog 32 has a length L extending beyond the end of the sleeve sufficient to protrude into and substantially bottom out in all notches, including final notch 29′ that has the greater depth.
Dog sleeve 30 and ratchet sleeve 12a are installed in a substantially coaxial manner within housing, are positioned axially offset from each other along axis x and are sized to be able to butt against each other at teeth 28 and dog 32. For example, the inner/outer diameters at teeth 28 and at dog 32 are selected such that the sleeves cannot telescope into one another at the location of the teeth and, instead, when the sleeves 12a and 30 are axially moved toward each other, the dog and teeth 28 and dog 32 are positioned to butt against, and mesh with, each other. For example, dog sleeve 30 at dog 32 has an outer diameter greater than the inner diameter of sleeve 12a at teeth 28.
Either or both of these sleeves 12a, 30 are axially and rotationally moveable to permit dog 32 and the first plurality of teeth 28 to move into and out of engagement and to permit the dog 32 to move from notch to notch along the first ratchet sleeve. In the illustrated embodiment, first ratchet sleeve 12a is rotationally and axially fixed within housing during indexing, while dog sleeve 30 is moveable both axially toward and away from sleeve 12a and rotationally about axis x, as shown by arrow R in
The indexing mechanism further includes a biasing member, such as spring 36, for biasing the parts of the indexing mechanism into one axial position. For example, the biasing member may urge the dog and the first plurality of teeth into one of (i) meshing engagement or (ii) out of meshing engagement. The biasing member is, however, able to be overcome to allow movement of the dog and the first plurality of teeth axially into the other of (i) meshing engagement or (ii) out of meshing engagement. In the illustrated embodiment, spring 36 urges the dog and the first plurality of teeth into meshing engagement, but spring 36 is able to be overcome by application of force against the spring force of spring 36, to allow movement of the dog and the first plurality of teeth axially away from each other and out of engagement. Thus, in the illustrated embodiment, spring 36 is positioned between a shoulder 37 on the housing and a shoulder 38 on dog sleeve 30 and spring 36 acts between these shoulders 37, 38 to bias dog sleeve 30 toward first ratchet sleeve 12a to normally ensure the meshing of dog 32 into a notch 29, 29′, but dog 32 can be removed from the notch in which it is positioned by applying a force to compress spring 36 and move sleeve 30 and dog 32 away from sleeve 12a. In the illustrated embodiment, the force may be applied to spring 36 through dog sleeve 30.
As noted above, an actuating mechanism may be employed for generating an application of force to act against spring 36. For example, the present tool is intended for use downhole and there are a few ways to apply a force against the spring when it is downhole. For example, an axial force may be applied by a string conveyed tool, such as on a wireline, a tubing string, etc. Alternately, an axial force may be applied hydraulically. For example, a piston that is in place or a piston that is established by landing a plug in a seat, may be employed for hydraulic actuation. The form of the actuating mechanism may be selected depending on the way in which the force is to be applied. For example, if driven by a string conveyed tool, the actuating mechanism may include the tool and a gland into which the tool lands and engages. In the illustrated embodiment, the axial force is applied hydraulically and the actuating mechanism includes an actuator, such as ball 40 as noted above, that lands on a ball seat in the tool, which in this embodiment, is the same seat 16 that will eventually move sleeve 12. The actuator may be free of any connection to surface such that it may be rapidly and simply conveyed to actuate the tool by being introduced at surface and conveyed by gravity or fluid flow to the seat. Once ball 40 lands on seat 16, an axial force is generated. The axial force may be from impact or through a hydraulic force. For example, seat 16 may simply act as a ball stop that receives impact force from the ball before the ball passes, or seat 16 may act as a ball stop that holds the ball in a sealing position relative to an uphole portion of the structure on which the seat is carried or alternately seat 16 may itself be formed to create a substantial seal with the ball across the inner diameter of seat and a pressure differential can be created across the seal, wherein the pressure uphole of the ball/seat is greater than the pressure downhole of the ball/seat and a force is applied toward the lower pressure side.
The force generated through the actuating mechanism, herein ball 40 and seat 16, drives dog 32 to move from notch to notch. For example, in this embodiment, the force, arrow A in
The actuating mechanism, therefore, may operate to only temporarily apply force such that the dog sleeve can be released to move into the next notch. In the case of a string conveyed tool, the string may be slacked off or picked up to discontinue the application of force or the tool may be disengaged from the indexing mechanism. In the case of a fluid pressure-based actuating mechanism, as illustrated, the fluid pressure, for example, the pressure differential may be dissipated. The fluid pressure may be dissipated from surface or any piston effect may be removed. In the presently illustrated embodiment, after an appropriate force is applied through seat 16, ball 40 is able to pass through seat 16 to remove the piston effect. For example, the ball may be selected to be deformable to pass through the seat or, as shown, seat 16 may be selected to be deformable to allow the ball to pass, after an appropriate force has been applied. Seat 16 is only temporarily deformable and rapidly resets to be ready to catch and seal with another ball such that the dog 32 can be moved to a further notch. In particular, in this illustrated embodiment, seat 16 includes a plurality of segments 16a that together form an annular seat structure. The seat segments normally protrude inwardly defining a normal seat ID to catch a suitably sized ball. However, seat segments 16a can be expanded outwardly to enlarge the seat to ID′ so that ball can pass through. In this embodiment, segments 16a can be moved axially along the tubular housing to align over openings 44 into which the seat segments can expand outwardly. When the seat segments expand outwardly into openings 44, the inner diameter of the seat is enlarged to ID′ and the ball can pass and continue down, as shown by arrow B in
As noted above, the indexing mechanism in this embodiment is selected to cause the dog sleeve to rotate or be rotated into alignment with a next notch 29 during or after the application of force. In the illustrated embodiment, the rotation is caused in part by the form of teeth 28, the form of dog 32 and the interaction thereof. Teeth 28 and dog 32 mesh axially, for example dog 32 can mesh with teeth 28 by axial movement toward sleeve 12a, but dog 32 can be removed from meshing engagement with teeth 28 by axial movement away from sleeve 12a. As noted above, teeth 28 and dog 32 include sloped surfaces defined by flanks 28b and side edge 32a, respectively, which when making contact, urge rotation of the dog sleeve relative to the first ratchet sleeve. In particular, when the dog's sloped side edge 32a is driven against rear flank 28b of a tooth, as by the force of spring 36, dog 32 is urged to slide along the slope of flank 28b until the dog bottoms out in notch 29. This sliding action causes the dog sleeve to rotate relative to first ratchet sleeve 12a.
In the illustrated embodiment, further components of the actuating mechanism also urge rotation of the dog sleeve. For example, the actuating mechanism includes an actuating sleeve 46 on which seat 16 is carried. Actuating sleeve 46 is positioned concentrically within first ratchet sleeve 12a and is axially moveable therein between a recessed position relative to teeth 28 and the notches (
Actuating sleeve 46 also includes a plurality of teeth on end 46a, for clarity referenced herein as the second plurality of teeth 48. Teeth 48 extend substantially parallel to the axis x. Each tooth of the plurality of teeth 48 includes a sloped front flank 48a and a sloped rear flank 48b that merge to form a point 48c. Flanks 48a, 48b extend in a direction along the circumference of the sleeve such that the end of the sleeve 46 has a saw tooth effect. In the illustrated embodiment, while the teeth are not at an end of the sleeve, the second plurality of teeth 48 extend from the sleeve with the flanks 48a, 48b axially exposed. As such, the actuating sleeve may also be termed a crown-type ratchet sleeve.
The number of teeth on actuating sleeve 46 is at least equal to the number of notches 29 on ratchet sleeve 12a. Teeth 48 are sized and positioned to correspond with the size and position of the teeth on sleeve 12a. In particular, teeth 48 are sized and positioned such that points 48c line up with notches 29 and, in particular, each point 48c lines up along a rear flank 28b of a tooth, between the tip 28c of a tooth and the bottom of the adjacent notch 29.
In the illustrated embodiment, the rotation of sleeve 30 is also caused in part by the interaction of teeth 48 against dog 32. Teeth 48 and dog 32 can mesh axially. As noted above, teeth 48 and dog 32 include sloped surfaces 48b and 32a, respectively, which when making contact, urge rotation of the dog sleeve relative to the actuation sleeve and the first ratchet sleeve. In particular, when sleeve 46 is driven axially by hydraulic pressure, the sloping surface of flank 48b drives against the dog's sloped side edge 32a (as is clearly shown in
In this illustrated embodiment, actuator sleeve 46 also acts with indexing mechanism to configure the seat 16 into an active position ready for use in the opening of ports 22.
Sleeve 12, for example, carries a lock ring 50 that is initially out of alignment with a gland 52 on sleeve 46. When the lock ring and the gland are out of alignment, the sleeves 12 and 46 can slide axially relative to each other. The lock ring and the gland remain out of alignment as long as the dog rides in notches 29, but when dog 32 enters deeper notch 29′, sleeve 46 is driven by dog 32 and the force of spring 36 axially further recessed back into sleeve 12, lock ring 50 aligns with gland 52 and snaps therein to lock the sleeves 12 and 46 together (
Sleeve 46 can be protected from inadvertent axial movement by provision of a pressure shield 56. Pressure shield is sealed by seals 58a against sleeve 12 and by seals 58b against an inner diameter of sleeve 46 to shield the upper end thereof from problematic pressure regimes, as may be generated for example by pressure drops generated by fluid passing through sleeve 46. Shield 56 is secured to sleeve 12 and sleeve 46 is axially moveable relative to the shield without restriction until sleeve 46 is locked to sleeve 12.
As will be appreciated, the downhole tool can include various components for appropriate operations. For example, seals 60 may be positioned between sleeve 12 and housing 20 to prevent fluid leakage and bypass. Torque pins, such as pins 62, 64 may be employed in slots to control against rotation of the parts. Pin 62 prevents relative rotation of sleeves 12a and 46 and pin 64 prevents rotation of sleeve 30 within housing 20 after ports 22 are opened. Also, if desired for balance and to prevent difficulties such as jamming, there may be more than one indexing set up, for example, a plurality of teethed regions including a plurality of notches 29 ending in notch 29′ and a dog for each plurality of teethed regions. For example, two dogs 32 can be seen in
Likewise, a mode of construction may be employed that best configures the parts and/or facilitates construction. For example, it is noted that many parts are formed of interconnected subcomponents.
The tool illustrated in
When cycling though inactive positions, as the ball 40 reaches seat 16, the ball hits the segments 16a. The force of the ball hitting the segments causes actuating sleeve 46 to move axially down until it extends axially beyond sleeve 12a and pushes on dog sleeve 30. This action pushes dog 32 out of the notch in which it was positioned. After sleeve 46 and the seat segments 16a it carries move far enough down that segments 16a expand out into openings 44, two things happen: dog sleeve 30 is rotated though a portion, for example half, of its intended rotation (by teeth 48 lifting dog 32 out of its notch 29 and flank 48b driving against side 32a of dog 32) and ball 40 can pass through segments 16a and proceed down hole. This is the position shown in
When the tool is reset into the penultimate notch (i.e. the notch before the final deep notch 29′), the next ball to land in seat 16 will cause dog sleeve 30 to rotate and move dog 32 into final deep notch 29′. When dog 32 enters notch 29′, this pushes actuating sleeve 46 a bit further uphole and gland 52 is aligned with ring 50 and a lock is formed between sleeve 46 and sleeve 12. Segments 16a can therefore no longer move into alignment with openings 44 and are held against collapsing and any ball 14 landing against seat 16 will move sleeve 12 along with sleeve 46 to open ports 22 in housing 20.
The indexing mechanism allows tool to be indexed through a plurality of inactive seat positions before a final active, non-collapsible seat is formed. It is noted that from
The indexing mechanism is durable since the shear forces that are generated during every cycle of the tool are absorbed through the indexing mechanism also in a fully axial direction, parallel to long axis x, through the dog, through its base and into sleeve 30. All meshing portions of the indexing mechanism also operate in the axial direction, which reduces damage and failure. For example, the axial forces generated by spring are absorbed axially through sleeve 12a and the axial force to move the tool through the indexing positions, which is that force arising from ball 40 landing in seat 16, passes axially through sleeve 46 and into the dog, through its base and into sleeve 30.
It is to be understood that modifications can be made to the tool and its indexing mechanism. For example, there could be two separate seats in the tool, one intended for collapsing to actuate the tool through the indexing positions and one that is normally held in an inactive position and only becomes active after the tool is indexed into the final active position.
As another option, the tool could be configured to actually open the sleeve when moving to the final position of the indexing mechanism.
As an example, another embodiment of a tool 110 with an indexing mechanism according to the present invention is shown in
The tool of
The sliding sleeve tools 10, 110 described above may be employed in methods which provide for selective communication to a wellbore for fluid treatment thereof. In one aspect of the invention the sliding sleeve tools and the methods provide for staged injection of treatment fluids wherein ports 22, 122 are opened to permit fluid to be injected into selected intervals of the wellbore, while other intervals are closed. In another aspect, the method may include running in of a fluid treatment string, the fluid treatment string having ports substantially closed against the passage of fluid therethrough, but which are each openable by operation of tools 10, 110 when desired to permit fluid flow into the wellbore.
In embodiments where cycling is of interest, the indexing mechanism may be used to allow the tool to cycle through a number of inactive positions before arriving at an active position, wherein seat 16 is formed non-collapsible (as in
In use, one or more of the tools with an indexing mechanism may be positioned in a tubing string. Because of their usefulness to increase the possible numbers of sleeves in any tubing string, the sliding sleeve tools may often be installed above one or more sleeves having a set valve seat. For example, with reference to
The sleeve furthest downhole, sleeve 634, includes valve seat 626b with a diameter D1 and the sleeve thereabove has valve seat 626a with a diameter D2. Diameter D1 is smaller than D2 and therefore sleeve 634 requires the smaller ball 623 to seal thereagainst, which can easily pass through the seat of sleeve 633. Actuating mechanism 638 of sleeve 632 includes a collapsible seat with an inner diameter D2.
This provides that the lowest sleeve 634 can be actuated to open first by launching ball 623 which can pass without effect through all of the sleeves 633, 632 thereabove but will land in and seal against seat 626b. Second sleeve 633 can likewise be actuated to move along tubing string 612 by ball 636 which is sized to pass through all of the sleeves thereabove to land and seal in seat 626a, so that pressure can be built up thereabove. However, in the illustrated embodiment, although ball 636 can pass through the sleeves thereabove, it may actuate those sleeves, for example sleeve 632, to generate valve seats thereon. For example, when ball 636 passes sleeve 632, the ball catches in actuating mechanism 638 and cycles the sleeve from one notch for an inactive position to a next notch for an active position and forms a non-collapsible seat. For example, actuating mechanism 638 on sleeve 632 includes the collapsible seat with a diameter D2 and is formed to be axially moved by ball 636 passing thereby cycle the indexing mechanism and create the non-collapsible seat. However, ball 636 does pass through sleeve 632 and the ball can continue to seat 626a.
Of course, where the first sleeve, with the configurable valve seat, is positioned above other sleeves with valve seats formable or fixed thereon, the formation of the valve seat on the first seat should be timed or selected to avoid interference with access to the valve seats therebelow. As such, for example, the inner diameter of any valve seat formed on the first sleeve should be sized to allow passage thereby of actuators (i.e. plugging balls or other plugs) for the valves therebelow. Alternately, and likely more practical, the timing of the actuation of the first sleeve to form a valve seat is delayed until access to all larger diameter valve seats therebelow is no longer necessary, for example all such larger diameter valve seats have been actuated or plugged.
In one embodiment as shown, the wellbore tubing string apparatus may be useful for wellbore fluid treatment and may include ports 617 over or past which sleeves 632, 633, 634 act.
In an embodiment where sleeves 632, 633, 634 are positioned to control the condition of ports 617, note that, as shown, in the closed port position, the sleeves can be positioned over their ports to close the ports against fluid flow therethrough. In another embodiment, the ports for one or both sleeves may have mounted thereon a cap extending into the tubing string inner bore and in the position permitting fluid flow, their sleeve has engaged against and opened the cap. The cap can be opened, for example, by action of the sleeve shearing the cap from its position over the port. Each sleeve may control the condition of one or more ports, grouped together or spaced axially apart along a path of travel for that sleeve along the tubing string. In yet another embodiment, the ports may have mounted thereover a sliding sleeve and in the position permitting fluid flow, the first sleeve has engaged and moved the sliding sleeve away from the first port.
The tubing string apparatus may also include outer annular packers 620 to permit the creation of isolated wellbore segments between adjacent packers. The packers can be of any desired type to seal between the wellbore and the tubing string. In one embodiment, at least one of the first, second and third packer is a solid body packer including multiple packing elements. In such a packer, it is desirable that the multiple packing elements are spaced apart.
In use, a wellbore tubing string apparatus, such as that shown in
The method can be useful for fluid treatment in a well, wherein the sleeves operate to open or close fluid ports through the tubular. The fluid treatment may be a process for borehole stimulation using stimulation fluids such as one or more of acid, gelled acid, gelled water, gelled oil, CO2, nitrogen and any of these fluids containing proppants, such as for example, sand or bauxite. The method can be conducted in an open hole or in a cased hole. In a cased hole, the casing may have to be perforated prior to running the tubing string into the wellbore, in order to provide access to the formation. In an open hole, the packers may be of the type known as solid body packers including a solid, extrudable packing element and, in some embodiments, solid body packers include a plurality of extrudable packing elements. The methods may therefore, include setting packers about the tubular string and introducing fluids through the tubular string.
Initially, as shown in
As shown in
Next, as shown in
Thereafter, as shown in
Thereafter, as shown in
When ball 736c passes through Interval 5, it moves sleeve 716e from inactive to active so that it can be shifted to the open position when desired.
Thereafter, as shown in
With reference to the tool of
When the ports are each opened, the formation accessed therethrough can be stimulated as by fracturing. It is noted, therefore, that the formation can be treated in a focused, staged manner. It is also noted that balls 736-736d may all be the same size, but still this portion of the formation can be treated in a focused, staged manner, through one port at a time. Note that while only five ports are shown in this segment of the string, more than five ports can be run in a string. The intervals need not be directly adjacent, as shown, but can be spaced and there can be more than one port/sleeve per interval (i.e. at least two ports in one interval that open after the same number of actuations or which open in sequence). Further similar series of ports could be employed above and/or below this series, which use other sized balls. Of course, any sleeves below that use a different sized ball will use a smaller ball that can pass through the illustrated sleeves without actuating them.
This system and tool of
The sleeves may sense the passing of a ball by various mechanisms, for example those as shown including deformable seats, deformable balls that squeeze through a fixed seat, or other mechanisms such a collets, c-rings, etc. As shown by sleeve 716a, the system can use combinations of solid ball seats and sleeves with indexing mechanisms. The system allows for installations of fluid placement liners of very long length forming large numbers of separately accessible wellbore zones.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to those embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the full scope consistent with the claims, wherein reference to an element in the singular, such as by use of the article “a” or “an” is not intended to mean “one and only one” unless specifically so stated, but rather “one or more”. All structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are know or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 USC 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or “step for”.
This application claims priority to U.S. provisional application Ser. No. 61/513,448, filed Jul. 29, 2011.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/CA12/50516 | 7/27/2012 | WO | 00 | 10/18/2013 |
Number | Date | Country | |
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61513448 | Jul 2011 | US |