Patent Application
20240141745
The unconventional market is extremely competitive. The market is trending towards longer horizontal wells to increase reservoir contact. Multilateral wells offer an alternative approach to maximize reservoir contact. Multilateral wells include one or more lateral wellbores extending from a main wellbore. A lateral wellbore is a wellbore that is diverted from the main wellbore or another lateral wellbore.
The lateral wellbores are typically formed by positioning one or more deflector assemblies at desired locations in the main wellbore (e.g., an open hole section or cased hole section) with a running tool. The deflector assemblies are often laterally and rotationally fixed within the main wellbore using a wellbore anchor, and then used to create an opening in the casing.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
In the drawings and descriptions that follow, like parts are typically marked throughout the specification and drawings with the same reference numerals, respectively. The drawn figures are not necessarily to scale. Certain features of the disclosure may be shown exaggerated in scale or in somewhat schematic form and some details of certain elements may not be shown in the interest of clarity and conciseness. The present disclosure may be implemented in embodiments of different forms.
Specific embodiments are described in detail and are shown in the drawings, with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure, and is not intended to limit the disclosure to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed herein may be employed separately or in any suitable combination to produce desired results.
Unless otherwise specified, use of the terms “connect,” “engage,” “couple,” “attach,” or any other like term describing an interaction between elements is not meant to limit the interaction to a direct interaction between the elements, and may also include an indirect interaction between the elements described. Unless otherwise specified, use of the terms “up,” “upper,” “upward,” “uphole,” “upstream,” or other like terms shall be construed as generally away from the bottom, terminal end of a well; likewise, use of the terms “down,” “lower,” “downward,” “downhole,” “downstream,” or other like terms shall be construed as generally toward the bottom, terminal end of a well, regardless of the wellbore orientation. Use of any one or more of the foregoing terms shall not be construed as denoting positions along a perfectly vertical axis. Unless otherwise specified, use of the term “subterranean formation” shall be construed as encompassing both areas below exposed earth and areas below earth covered by water, such as ocean or fresh water.
The present disclosure is based, at least in part, on an isolation mechanism (e.g., whipstock isolation mechanism), for example used below the whipstock to block cement and debris while milling a window in the wellbore casing. The objectives of the isolation mechanism, among others, include: 1) the ability to hold pressure (e.g., provided by customer) after the isolation element is set; 2) the ability to remain set and hold pressure during the milling; 3) the ability to unset the isolation element when retrieving the isolation mechanism by pulling from above, for example to prevent swabbing that may result when pulling out of hole with an expanded isolation element; and 4) the ability for the isolation mechanism to be adjusted to easily handle different downhole conditions.
The present disclosure has recognized that the downhole wellbore casing inside diameter (ID) and downhole wellbore temperature greatly affect the ability of the isolation mechanism to be set, to provide the requisite amount of isolation when set, as well as to be unset when needed. Accordingly, the present disclosure provides an adjustable isolation mechanism, which can easily accommodate changes in the downhole wellbore casing ID and/or downhole wellbore temperatures. The adjustable isolation mechanism can be used for different downhole casing IDs. For example, the adjustable isolation mechanism can be adjusted to be easily set in minimum downhole casing IDs to maximum downhole casing IDs. Based on FEA results, for minimum downhole casing IDs, the setting force and stroke length are much smaller than those for maximum downhole casing IDs. The adjustable isolation mechanism gives the opportunity to control the proper setting force and stroke length for different downhole casing IDs and then hold for required pressure. See
Similarly for different downhole casing IDs, the isolation elements perform differently with different temperatures. For example, contrary to conventional thinking, the present disclosure recognizes that the required stroke length to set the isolation elements at higher temperatures is smaller than the required stroke length to set the isolation elements at lower temperatures (e.g., based on FEA and test result within the same downhole wellbore casing ID). Accordingly, if the adjustable isolation mechanism will be run in the well at higher temperatures, lower setting load and stroke length are required for holding a required pressure, whereas if the adjustable isolation mechanism will be run in the wellbore at lower temperatures, higher setting load and stroke length will be required to hold the same required pressure. See
Given the foregoing, the present disclosure has recognized that to make the adjustable isolation mechanism work properly, it may be helpful (e.g., if not imperative) to determine the downhole conditions, such as downhole wellbore casing ID, downhole wellbore temperature, and required holding pressure. With this information, some FEA simulations or tests may be conducted to get the proper stroke length and/or setting force for the determined downhole conditions. Accordingly, the adjustable isolation mechanism may be appropriately assembled with the proper stroke capacity and/or retaining shear mechanism to set the isolation elements, hold the isolation elements, and release the isolation elements, when needed.
As one example, the FEA simulations shown in
In at least one embodiment, the present disclosure achieves the adjustability by including a row of slip ring shear feature openings (e.g., at least two rows of slip ring shear feature openings) in the slip ring of the adjustable isolation mechanism. Furthermore, the present disclosure achieves the adjustability by including a row of shear mandrel shear feature openings (e.g., at least two rows of shear mandrel shear feature openings) in the shear mandrel. For example, ones of shear features could be placed within one row of slip ring shear feature openings (e.g., first row of slip ring shear feature openings) and one row of shear mandrel shear feature openings (e.g., first row of shear mandrel shear feature openings), thereby shearingly coupling the slip ring to the shear mandrel. Alternatively, ones of shear features could be placed within ones of the second row of slip ring shear feature openings and second row of shear mandrel shear feature openings, thereby shearingly coupling the slip ring to the shear mandrel. In yet another embodiment, ones of shear features could be placed within ones of the first and second rows of slip ring shear feature openings and first and second rows of shear mandrel shear feature openings, thereby shearingly coupling the slip ring to the shear mandrel, for example to increase the shear force between the slip ring and shear mandrel. In yet other embodiments, three, four, five, or more rows of slip ring shear feature openings and shear mandrel shear feature openings exist, and different amounts of ones of shear features may be positioned in one or more of the rows to increase the shear force between the slip ring and the shear mandrel.
In at least one embodiment, the present disclosure also achieves the adjustability by increasing a stroke gap between the stroke sleeve and the isolation element mandrel to a value sufficient to accommodate most, if not any and all, downhole conditions (e.g., downhole casing ID, downhole wellbore temperature, hold pressure, etc.). With this increased stroke gap, a number of stroke adjustment spacers may be placed between the stroke sleeve and the downhole support shoe (e.g., upper support shoe in one embodiment) to adjust for the specific downhole conditions (e.g., the specific known downhole wellbore casing ID, downhole wellbore temperature, hold pressure, etc.).
In at least one embodiment, the process flow might go as follows: 1) before assembly, collect operational data for the wellbore, including downhole wellbore casing ID, downhole wellbore temperature, and downhole holding pressure; 2) perform FEA simulation for the isolation elements based upon the collected operational data, including simulating the proper setting force necessary to hold the required pressure, at a similar time, determining a stroke length at the setting load (e.g., or perform simplified setting and pressure test to get the data); 3) due to the large tolerance of the isolation elements, assemble the adjustable isolation mechanism with an appropriate number of stroke adjustment spacers (e.g., to adjust the stroke gap to be at the stroke as simulated or tested for the collected downhole wellbore casing ID and downhole wellbore temperature); and 4) install the proper number of shear features within the rows of shear feature openings in the slip ring and the shear mandrel (e.g., enough shear features to hold the setting load). It should be noted that too few shear features will not be strong enough to hold the energized isolation element, and to many shear features might have trouble when the system needs to shear to unset the isolation element to pull the adjustable isolation mechanism out. Thus, the ability to easily adjust the shear force (e.g., within the range discussed above) is an important part of the disclosure.
The adjustable isolation mechanism may include other important features while remaining within the scope of the disclosure. In at least one embodiment, the adjustable isolation mechanism includes a set of head screws aligned in a groove of the body lock ring to prevent the body lock ring from rotating (e.g., preventing it from un-threading from the stroke sleeve). In at least one other embodiment, a spring may be added in a gap between body lock ring and upper shoulder in the compressed position (e.g., to prevent or reduce the back lash from the body lock ring when it engages). In even yet another embodiment, grease or rubber material can be applied into the increased stroke gap and unset gap (e.g., to reduce impact load when set on the isolation element, and reduce debris from getting into critical areas of the device).
As shown, a main wellbore 150 has been drilled through the various earth strata, including the subterranean formation 110. The term “main” wellbore is used herein to designate a wellbore from which another wellbore is drilled. It is to be noted, however, that a main wellbore 150 does not necessarily extend directly to the earth's surface, but could instead be a branch of yet another wellbore. A casing string 160 may be at least partially cemented within the main wellbore 150. The term “casing” is used herein to designate a tubular string used to line a wellbore. Casing may actually be of the type known to those skilled in the art as a “liner” and may be made of any material, such as steel or composite material and may be segmented or continuous, such as coiled tubing. The term “lateral” wellbore is used herein to designate a wellbore that is drilled outwardly from its intersection with another wellbore, such as a main wellbore. Moreover, a lateral wellbore may have another lateral wellbore drilled outwardly therefrom.
In the embodiment of
The whipstock assembly 170, in at least one embodiment, includes a whipstock element section 175, as well as an anchoring/sealing subassembly 180 coupled to a downhole end thereof. The anchoring/sealing subassembly 180, in one or more embodiments, includes an orienting receptacle section 182, a sealing section 184, and a latching element section 186. In at least one embodiment, the latching element section 186 axially, and optionally rotationally, fixes the whipstock assembly 170 within the casing string 160. The sealing section 184, in at least one embodiment, seals (e.g., provides a pressure tight seal to) an annulus between the whipstock assembly 170 and the casing string 160. In at least one embodiment, the sealing section 184 includes an adjustable isolation mechanism, as discussed above. The orienting receptacle section 182, in one or more embodiments, along with a collet and one or more orienting keys, may be used to land and positioned a guided milling assembly and/or the whipstock element section 175 within the casing string 160.
The elements of the whipstock assembly 170 may be positioned within the main wellbore 150 in one or more separate steps. For example, in at least one embodiment, the anchoring sub assembly 180, including the orienting receptacle section 182, sealing section 184 and the latching element section 186 are run in hole first, and then set within the casing string 160. Thereafter, the sealing section 184 may be pressure tested. Thereafter, the whipstock element section 175 may be run in hole and coupled to the anchoring/sealing subassembly 180, for example using the orienting receptacle section 182. What may result is the whipstock assembly 170 illustrated in
Turning now to
Turning to
Turning to
The anchoring/sealing subassembly 400, in the illustrated embodiment, additionally includes one or more setting shear features 420. In one or more embodiments, the one or more setting shear features 420 are used hold the isolation element 410 in its radially retracted state while running in hole, and thus allowing a flow path for cleaning the wellbore. The anchoring/sealing subassembly 400, in one or more embodiments, additionally includes a ratch latch body 430 (e.g., including a stroke sleeve 430a, body lock ring 430b, and slip ring 430c in one or more embodiments) for locking the isolation element 410 at a position while setting. The anchoring/sealing subassembly 400, in accordance with one embodiment of the disclosure, additionally includes a shear mandrel 440 (e.g., rigidly coupled to the isolation element mandrel 405).
In accordance with one embodiment of the disclosure, the slip ring 430c includes at least one row (e.g., at least two axially offset rows) of slip ring shear feature openings 435 and the shear mandrel 440 includes at least one row (e.g., at least two axially offset rows) of shear mandrel shear feature openings 445. In at least one embodiment, the anchoring/sealing subassembly 400 may include at least 3, at least 4, at least 5, at least 6, etc. of rows of slip ring shear feature openings 435 and shear mandrel shear features openings 445 (e.g., each row including 2, 4, 8, 12, 16, 20, etc. radially spaced individual shear openings). Depending on the design of the device, ones of shear features 450 may be located in one or more of the rows of slip ring shear feature openings 435 and shear mandrel shear feature openings 445 to shearingly couple the sling ring 430c to the shear mandrel 440. For example, as discussed above, the downhole wellbore casing ID, downhole wellbore temperature, and/or setting pressure may be determined and used to decide how many shear features 450 are located in the ones of the rows of slip ring shear feature openings 435 and shear mandrel shear feature openings 445, thus setting up the adjustable isolation mechanism.
The anchoring/sealing subassembly 400, in at least one embodiment, may further include an increased stroke gap 460, as discussed above. The increased stroke gap 460, in this embodiment, sets the stroke length between the stroke sleeve 430a and the isolation element mandrel 405, which in turn sets the stroke length of the upper support shoe 470 on the isolation element 410. The anchoring/sealing subassembly 400, in at least one embodiment, may further include (e.g., may add or remove) one or more stroke adjustment spacers 465 between the stroke sleeve 430a and the upper support shoe 470. As discussed above, the inclusion of the increased stroke gap 460 and/or one or more stroke adjustment spacers 465 allows for the setting force to be tailored (e.g., infinitely tailored). The one or more stroke adjustment spacers 465 may be one or more similarly sized stroke adjustment spacers, or alternatively may be one or more different sized stroke adjustment spacers.
To properly design the increased stroke gap 460 and/or the number and size of the one or more stroke adjustment spacers 465, FEA simulations of the isolation element 410 positioned at conditions similar to the downhole conditions that the isolation element will ultimately be located is helpful, if not necessary. Again,
Returning to
Turning to
The anchoring/sealing subassembly 500 may be run-in-hole, for example in the state shown in
When it is time to unset the isolation element 410, and thus pull the anchoring/sealing subassembly 500 uphole, the whipstock assembly may be pulled uphole to shear the shear features 450 (e.g., as shown in
At this stage, the anchoring/sealing subassembly 500 is ready to be pulled uphole without worrying about swabbing (e.g., as shown in
Aspects disclosed herein include:
Aspects A, B, and C may have one or more of the following additional elements in combination: Element 1: wherein wherein the row of radially spaced apart slip ring shear feature openings is a first row of radially spaced apart slip ring shear feature openings, and further including a second row of radially spaced apart slip ring shear feature openings axially offset from the first row of radially spaced apart slip ring shear feature openings, and further wherein the row of radially spaced apart shear mandrel shear feature openings is a first row of radially spaced apart shear mandrel shear feature openings, and further including a second row of radially spaced apart shear mandrel shear feature openings axially offset from the first row of radially spaced apart shear mandrel shear feature openings, the first and second rows of slip ring shear feature openings and the first and second rows of shear mandrel shear feature openings operable to receive ones of shear features to shearingly couple the slip ring and the isolation element mandrel together. Element 2: wherein further including ones of shear features located in the first and second rows of the slip ring shear feature openings and the first and second rows of the shear mandrel shear feature openings. Element 3: further including ones of shear features located in the row of the slip ring shear feature openings and the row of the shear mandrel shear feature openings. Element 4: further including an increased stroke gap located between the stroke sleeve and the isolation element mandrel. Element 5: further including a dampening material located in the increased stroke gap, the dampening material configured to reduce backlash that may be generated when the ones of the shear features shear. Element 6: wherein the dampening material is a fluid dampener. Element 7: further including an upper support shoe positioned between the stroke sleeve and the isolation element. Element 8: further including one or more stroke adjustment spacers located between the stroke sleeve and the upper support shoe. Element 9: wherein two or more different sized spacers are located between the stroke sleeve and the upper support shoe.
Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions and modifications may be made to the described embodiments.
This application claims the benefit of U.S. Provisional Application Ser. No. 63/419,379, filed on Oct. 26, 2022, entitled “ADJUSTABLE WHIPSTOCK ISOLATION MECHANISM,” commonly assigned with this application and incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63419379 | Oct 2022 | US |
