Patent Grant
11313225
This disclosure relates to apparatus, systems, and methods of collecting core samples, and more particularly to collecting sidewall cores while drilling.
Core data is often used as a reference for other wellbore measurements, such as for interpreting logs and well tests for lithology, porosity, permeability, wettability, fluid content, as well as fluid properties such as viscosity, density, and compressibility. As such, collecting formation core samples is a crucial part of oil and gas exploration and development. Conventional coring is typically performed by replacing a drilling bit with a coring bit when the top of a targeted zone to be cored is reached. However, this process requires pulling the drillstring out of wellbore multiple times to perform bit replacement and to perform multiple coring runs in order to capture multiple cores with a particular limited core length (such as 30 feet long).
Alternatively wireline sidewall coring tools can be used to obtain sidewall core samples at targeted intervals. However, sidewall coring using wireline tools also requires that the drilling assembly be removed from the wellbore in order to run the wireline coring tool into the wellbore, which can be time-consuming and, therefore, costly, especially in high angle and horizontal wells where wireline needs to be replaced by coil tubing or drill pipe for conveying sidewall coring tools.
In addition, in situations where borehole stability is an issue, such as wellbores containing washouts, conventional coring and wireline sidewall coring tools cannot be used to effectively capture core samples. It is also very difficult and costly to conduct conventional coring or wireline side-wall coring in highly deviated wells or horizontal wells, especially in very long total depth wells located in challenging environments such as deep water wells, for which making a trip in and out of the well can be a time consuming cost prohibitive operation.
In an example implementation, a system includes a bottom hole assembly and a core sampling tool. The bottom hole assembly includes a housing and a drill bit coupled to the housing. The core sampling tool includes a first compartment positioned within the housing, the first compartment including a motor; a second compartment positioned within the housing and radially spaced apart from the first compartment, the second compartment including a coring bit; and a flexible drilling shaft extending between and coupled to the motor and the coring bit.
This, and other implementations, can include one or more of the following features. The first compartment and the second compartment can be vertically spaced apart within the housing of the bottom hole assembly. The first compartment can include a first actuator configured to raise and lower the motor within the first compartment. The second compartment can include an opening through the housing; and a sealing door configured to seal the opening; and lowering the motor within the first compartment can cause the coring bit to extend outside the second compartment through the opening when the sealing door is positioned above the opening. The second compartment can include a second actuator configured to raise and lower the sealing door within the second compartment; and positioning the sealing door above the opening can include causing the second actuator to retract a connecting rod coupled to the sealing door. The sealing door can be configured to seal the opening during drilling operations. The second compartment can include a core storage container. The coring bit can be configured to rotate to deposit a core sample within the core storage container. The coring bit can coupled to the flexible drilling shaft using one or more locking joint pins; and the second compartment can include a locking joint pin releaser configured to unlock the one or more locking joint pins coupled to the coring bit. The second compartment can include a rotatable actuator configured to rotate the coring bit within the second compartment. Rotating the coring bit to deposit core samples within the core storage container can include inserting the one or more locking joint pins into the locking joint pin releaser to unlock the one or more locking joint pins; and actuating the rotatable actuator to rotate the coring bit within the second compartment. The second compartment can include a second connecting rod coupled to the rotatable actuator; and a rotatable bit housing coupled to the rotatable actuator, the rotatable bit housing encircling the coring bit when the coring bit is positioned with the second compartment; and actuating the rotatable actuator to rotate the coring bit within the second compartment can include causing the actuator to extend the second connecting rod. The second compartment can include a third actuator; and a core disposing pin coupled to the third actuator. Depositing the core sample within the core storage container can include rotating the coring bit from a neutral position to a depositing position over the core storage container; and extending the core disposing pin using the third actuator through the coring bit. The second compartment can include a fourth actuator; and a plug coupled the fourth actuator and configured to seal the core storage container. Sealing the core storage container can include determining that the core storage container is full; in response to determining that the core storage container is full, actuating the fourth actuator to position the plug over the core storage container; and inserting the plug into the core storage container. Inserting the plug into the core storage container can include extending the core disposing pin using the third actuator to press the plug into the core storage container. The system can include an anchor shoe configured to stabilize the bottom hole assembly within a wellbore; and a third compartment within the housing, the third compartment including a fifth actuator; a first leg rotatably coupled to the anchor shoe and the fifth actuator; and a second leg rotatably coupled to the anchor shoe and the third compartment. The third compartment can be vertically spaced apart from the first compartment and the second compartment and radially spaced apart from the second compartment within the housing.
In some implementations, a core sampling tool includes a first compartment positioned within a housing, the first compartment including a motor; a second compartment positioned within the housing and radially spaced apart from the first compartment, the second compartment including a coring bit; and a flexible drilling shaft extending between and coupled to the motor and the coring bit. The coring bit is configured to cut core samples from a targeted formation.
Example embodiments of the present disclosure may include one, some, or all of the following features. For example, a core sampling tool according to the present disclosure may be used during drilling operations without requiring removal of the drilling tool from the wellbore. As a result, a core sampling tool according to the present disclosure may reduce the time and cost required to collect core samples by allowing for core sampling during drilling operations. In addition, a core sampling tool according to present disclosure may minimize flow restrictions along the drill pipe as a result of the radially offset chambers of the core sampling tool. A core sampling tool according to the present disclosure may also allow for sampling in deeper portions of a formation compared to sampling with traditional sampling tools. A core sampling tool according to the present disclosure may enable core sampling in highly deviated wells and/or horizontal wells. In addition, a core sampling tool according the present disclosure may allow for core sampling in boreholes with stability problems, such as wellbores with borehole washouts.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
The present disclosure describes a sidewall core sampling tool and system for capturing one or more core samples from a wellbore.
The bottom hole assembly 126 coupled with the drillstring 110 may be used to form the wellbore 112. The wellbore 112 may be formed to extend from the terranean surface 102 through one or more geological formations in the Earth. One or more subterranean formations, such as subterranean zone 114, are located under the terranean surface 102. One or more wellbore casings, such as surface casing 106 and intermediate casing 108, may be installed in at least a portion of the wellbore 112.
Although shown as a wellbore 112 that extends from land, the wellbore 112 may be formed under a body of water rather than the terranean surface 102. For instance, in some embodiments, the terranean surface 102 may be a surface under an ocean, gulf, sea, or any other body of water under which hydrocarbon-bearing, or water-bearing, formations may be found. In short, reference to the terranean surface 102 includes both land and underwater surfaces and contemplates forming or developing (or both) one or more wellbores 112 from either or both locations.
As depicted in
In some aspects, the drillstring 110 may be a tubular work string made up of multiple tubing joints. For example, a tubular work string typically consists of sections of steel pipe, which are threaded so that they can interlock together.
Once the wellbore 112 is formed (or in some cases during portions of forming the wellbore 112), one or more tubular casings may be installed in the wellbore 112. As illustrated, the wellbore 112 includes a conductor casing 104, which extends from the terranean surface 102 shortly into the Earth. A portion of the wellbore 112 enclosed by the conductor casing 104 may be a large diameter borehole.
Downhole of the conductor casing 104 may be the surface casing 106. The surface casing 106 may enclose a slightly smaller borehole and protect the wellbore 112 from intrusion of, for example, freshwater aquifers located near the terranean surface 102. The wellbore 112 may then extend vertically downward and/or horizontally outward. This portion of the wellbore 112 may be enclosed by the intermediate casing 108. In some aspects, the location in the wellbore 112 at which the sidewall core sampling tool 116 is moved to may be an open hole portion (for example, with no casing present) of the wellbore 112.
As depicted in
As shown in
As illustrated in
The control system 125 may be a microprocessor-based, mechanical, or electromechanical controller, as some examples. The control system 125, in some aspects, may send and receive data between it and the sidewall core sampling tool 116, as well as, for example, provide electrical power to the sidewall core sampling tool 116. The control system 125 may perform one or more operations described in the present disclosure to operate all or parts of the sidewall core sampling tool 116. In some implementations, the control system 125 is a computer-readable medium (for example, a non-transitory computer-readable medium) storing instructions executable by one or more processors to perform operations described in this disclosure. In some implementations, the control system 125 includes firmware, software, hardware, processing circuitry or combinations of them that can perform operations described in this disclosure.
Referring to
As depicted in
In some implementations, the first compartment 120 includes a seal 218 that is positioned around the actuator 206. The seal 218 is positioned to seal off and prevent fluid from contaminating the computer 204 and the battery 202.
As can be seen in
As depicted in
The coring bit 224 is configured to collect sidewall core samples from the surrounding wellbore 112. As will be described in further detail herein, as the drilling shaft 132 is lowered and rotated by the motor 208, the coring bit 224 is simultaneously pushed laterally outside the housing 130 through an opening 228 in the housing 130 towards the surface of the wellbore 112 and is rotated to cut a core sample from the subterranean zone 114. In some implementations, the coring bit 224 is a hollow bit that includes a central opening that extends along the length of the coring bit 224, and core samples are collected within the central opening of the coring bit 224.
In some implementations, the core sampling tool 116 includes a sealing door 230 that is configured to selectively cover and uncover the opening 228 in the housing 130 proximate the second compartment 122. For example, as depicted in
As can be seen in
Referring to
Referring to
Once a core sample has been collected within the central opening of the coring bit 224, the actuator 206 can be used to draw the motor 208 uphole, which applies a force to the drilling shaft 132 and coring bit 224. As a result, the coring bit 224 is withdrawn horizontally into the second compartment 122 until the coring bit 224 is positioned within the neutral position 238, as depicted in
Referring to
As can be seen in
In some implementations, the computer 204 monitors the length of extension of the disposing pin 254 to determine when the core storage container 226 is full. For example, once the computer 204 detects that the disposing pin 254 has extended less than a threshold length during a core deposition cycle, the computer 204 determines that the core storage container 226 is full and causes the third fixed actuator 256 to extend to push the plug 258 over the opening of the core storage container 226. In some implementations, the length of the core storage container 226 can be configured to house a predetermined number of core samples.
As can be seen in
In some implementations, the core storage container 226 includes one or more threads 260, which can be used to couple the core storage container 226 to the core sampling tool 116. For example, after core sampling has been performed and the core sampling tool 116 has been retrieved to the surface 102, the core storage container 226 can be unthreaded from the core sampling tool 116 via threads 260 with plug 258 still in place to preserve the condition of the core samples contained within the core storage container 226.
Referring to
As can be seen in
In order to operate the anchor shoe 272 to position the core sampling tool 116 against the wellbore 112, actuator 274 extends the connecting rod 276, which causes the legs 278, 280 coupled the anchor shoe 272 to rotate about the knuckle joints 282, 284, 286 and the end of the legs 278, 280 opposite the anchor shoe 272 to move towards one another, which pushes the anchor shoe 272 outwards away from the housing 130 and towards the wellbore 112. Upon contacting the wellbore 112, the anchor shoe 272 pushes against the wellbore 112, and the force applied to the wellbore 112 by the anchor shoe 272 pushes the core sampling tool 116 towards the opposite side of the wellbore 112 such that the coring bit 224 of the core sampling tool 116 can contact the wellbore 112.
As can be seen in
For example,
A process of collecting core samples will now be described with reference to
Referring to
In some implementations, upon positioning the core sampling tool 116 at the target depth, the drilling assembly 126 (and, thus, the core sampling tool 116) is rotated within the wellbore 112 in order to align the opening 228 in the housing 130 of the bottom hole assembly 126 with the targeted formation 114. For example, as depicted in
In some implementations, prior to performing core sampling, the wellbore 112 is flushed with fluids in order to clean drill cuttings out of the wellbore 112. For example, fluid can be circulated into the wellbore 112 and through the housing 130 of the bottom hole assembly 125 in order to clean the wellbore 112.
As depicted in
Referring to
Referring to
Referring to
Once the coring bit 224 is positioned in the sampling position 242, the motor 208 can be further lowered by the actuator 206 to press the end of the coring bit 224 against the wellbore 112. In addition, the motor 208 can be engaged (e.g., by computer 204) to rotate the drilling shaft 132, which rotates the coring bit 224 into the sidewall of the wellbore 112 to obtain a core sample from the target formation 114. In some implementations, the motor 208 is rotated clockwise, which results in clockwise rotation of the coring bit 224 into the formation 114, as depicted in
While the coring bit 224 is in the sampling position 242, the knuckle joints 402, 404 can be used to maintain the position of the coring bit 224 relative to the bottom hole drilling tool 126 such that the coring bit is substantially horizontal to the housing 130 of the bottom hole drilling tool 126 when in the sampling position 242. For example, as depicted in
Referring to
The coring bit 224 continues to be withdrawn into the second compartment 122 until the joint lock pin releaser 406 releases the knuckles joints of the coring bit 224 so that the coring bit 224 can be transitioned into the core depositing position 240. For example, as depicted in
Referring to
Referring to
As depicted in
Referring to
Still referring to
Once the sealing door 230 is positioned to seal opening 228 and the anchor shoe 272 is withdrawn from the surface of the wellbore 112, the bottom hole assembly 126 can be repositioned within the wellbore 112 for additional core sampling. For example, the bottom hole assembly 126 can be raised or lowered within the wellbore 112 to position the sidewall core sampling tool 116 proximate a second target formation for core sampling. Once the sidewall core sampling tool 116 is positioned proximate another target formation, the process for core sampling described above in reference to
Once the core storage container 226 is filled with core samples 702, 704, 706, 708, the core storage container 226 can be sealed to protect and store the core samples 702, 704, 706, 708 for subsequent analysis. Referring to
In some implementations, the computer 204 monitors the length of extension of the disposing pin 254 to determine whether the core storage container 226 is full. For example, once computer 204 detects that the disposing pin 254 has extended less than a threshold length during a sample deposition cycle, the computer 204 determines that the core storage container 226 is full and causes fixed actuator 256 to extend and position the plug 258 over the opening of the core storage container 226. As depicted in
Referring to
Referring to
Further, once the core storage container 226 is sealed with plug 258, the bottom hole assembly 126 can be repositioned within the wellbore 112 for additional drilling operations or can be withdrawn from the wellbore 112 (e.g., if drilling operations are complete). For example, as depicted in
Once core sampling and drilling operations are completed, the bottom hole assembly 126 and core sampling tool 116 can be withdrawn uphole and out of the wellbore 112. Once the core sampling tool 116 has been retrieved to the surface 102, the core storage container 226 can be unthreaded from the core sampling tool 116 via threads 260 with plug 258 still in place to preserve the condition of the core samples 702, 704, 706708 contained within the core storage container 226 during transport of the core storage container 226. Once the core storage container 226 has been decoupled from the core sampling tool 116 and transported to a location for analysis of the core samples (e.g., a laboratory), plug 258 can be removed and the core samples 702, 704, 706708 contained within the core storage container 226 can be accessed for analysis.
While the core sampling tool 116 has been depicted as being deployed in a vertical wellbore, some implementations, the core sampling tool 116 can be used in a horizontal wellbore. For example, when deploying the core sampling tool 116 in a horizontal wellbore, the bottom hole assembly 126 and core sampling tool 116 can be rotated to orient the opening 228 in the housing 130 to face the direction of gravity. In addition, when the core sampling tool 116 is deployed in a horizontal wellbore, the use of an anchor shoe (such as anchor shoe 272) may not be required as the housing 130 of the bottom hole assembly 126 can rest against the horizontal wellbore.
While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any claims or of what may be claimed, but rather as descriptions of features specific to particular implementations. Certain features that are described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.
Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.
A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. For example, example operations, methods, or processes described herein may include more steps or fewer steps than those described. Further, the steps in such example operations, methods, or processes may be performed in different successions than that described or illustrated in the figures. Accordingly, other implementations are within the scope of the following claims.
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| Number | Date | Country | |
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| 20220065104 A1 | Mar 2022 | US |
