LOGGING DRONE WITH WIPER PLUG

Abstract

An autonomous logging drone tool-string including a wiper plug at a downstream end, a logging tool, and a detachable transmitter capsule, and associated methods for cementing a wellbore and logging wellbore information in a single tool-string run downhole. In an aspect, the logging drone tool-string may include a perforating gun and associated methods may include perforating a toe end of the wellbore casing and surrounding cement. In an aspect, the transmitter capsule stores wellbore information from the logging tool. The transmitter capsule may be detached, pumped to the surface, and retrieved for accessing the stored wellbore information.

Description

BACKGROUND OF THE DISCLOSURE

The present disclosure is generally directed to wellbore completion operations. As shown in the cross-sectional view of FIG. 1, a typical wellbore site 100 includes a wellbore 101 that has been drilled into a hydrocarbon formation 130 and extends from a surface 110 of the wellbore 101/hydrocarbon formation 130 to an end, or toe 111, of the wellbore 101. As part of preparing the wellbore 101 for perforating and completion operations to extract oil and/or gas from the hydrocarbon formation 130, a wellbore casing 120, as multiple segments, is inserted into the wellbore 101. The configuration/profile of the wellbore casing 120 generally matches the profile of the wellbore 101 but a diameter of the wellbore casing 120 is less than a diameter of the wellbore 101 so as to leave an annulus 121 of generally empty space between the wellbore casing 120 and the surrounding hydrocarbon formation 130.

A cement slurry 140 is then pumped down the wellbore casing 120 which is open at the toe end 111 to allow the cement slurry 140 to fill the toe end 111 of the wellbore 101. The pump-down pressure forces the cement slurry 140 to then fill the annulus 121 around the wellbore casing 120, from the toe end 111 towards the surface 110, to seal the wellbore casing 120 within the wellbore 101. After a sufficient amount of cement slurry 140 has been pumped into the wellbore 101, a wiper plug (or, “cement plug”) 210 (FIG. 3) is deployed into the wellbore casing 120 to force any remaining cement slurry 140 out of the wellbore casing 120, towards the toe end 111 and into the annulus 121, as is known.

Once the above cementing operations are complete, a wellbore tool such as a perforating gun may be deployed into the wellbore casing 120 to perform a completion operation such as perforating the wellbore casing 120, surrounding cement 140, and hydrocarbon formation 130, to recover the hydrocarbons. However, before performing additional wellbore operations, a logging device (not shown) may be pumped down the wellbore casing 120 on a conveyance such as a wireline, e-line, coiled tubing or e-coil, to log the structural layout of the wellbore 101 and other wellbore conditions by, e.g., logging and recording the position of magnetic markers, beacons, casing couplings, and the like. Generating a profile of the wellbore 101 and the conditions at various locations within the wellbore casing 120 may allow operators to position wellbore tools more precisely during various operations.

As described above, known techniques for performing the above operations require multiple “runs” into the wellbore 101; i.e., each of the wiper plug, logging device, and perforating gun (or other wellbore tool) must be separately deployed into the wellbore 101. The logging device and perforating gun must be conveyed on a physical conveyance, and thereafter removed from the wellbore by the physical conveyance. Further, the logging device and perforating gun, for example, may require a communicative electrical connection (e.g., as a component of the physical conveyance) to computers at the surface 110 for providing initiating and other instructions to the devices, and sending information from the logging device to the surface. These aspects increase the time, cost, and personnel required for wellbore preparation.

Accordingly, devices, systems, and methods for combining the above operations and eliminating the need for physical connections between wellbore tools and the surface of the wellbore would be beneficial.

BRIEF DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

In an aspect, the disclosure relates to an autonomous logging drone tool-string. The autonomous logging drone tool string may comprise a wiper plug at a downstream end, a logging tool, and a transmitter capsule in electrical communication with the logging tool. The transmitter capsule may be configured for detaching from the logging drone tool-string.

In an aspect, the disclosure relates to an autonomous logging drone that may comprise a wiper plug, a perforating gun, a trigger module, a logging tool, and a transmitter capsule. Each of the wiper plug, the perforating gun, the trigger module, the logging tool, and the transmitter capsule may be connected as a tool-string, and the wiper plug may be positioned at a downstream end of the tool-string.

In an aspect, the disclosure relates to a method for cementing a wellbore and logging wellbore information. The method may comprise pumping cement down a wellbore casing within the wellbore and deploying a logging drone into the wellbore casing. The logging drone may include a wiper plug at a downstream end and a logging tool positioned upstream of the wiper plug. The logging drone may include a transmitter capsule in electrical communication with the logging tool. The method may further comprise pumping the logging drone down the wellbore casing with a wellbore fluid and pushing cement out of the wellbore casing with the wiper plug. The method may further comprise collecting wellbore information with the logging tool and storing the wellbore information in the transmitter capsule. The method may further comprise retrieving the wellbore information from the transmitter capsule.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description will be rendered by reference to exemplary embodiments that are illustrated in the accompanying figures. Understanding that these drawings depict exemplary embodiments and do not limit the scope of this disclosure, the exemplary embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a cross-sectional view of a typical wellbore site and wellbore;

FIG. 2 is a side view of a logging drone with wiper plug according to an exemplary embodiment;

FIG. 3 is a partial cross-sectional view of a wiper plug according to an exemplary embodiment;

FIG. 4 is a breakout view of a logging drone with wiper plug according to an exemplary embodiment;

FIG. 5 is a cross-sectional view of a ballistic release tool according to an exemplary embodiment;

FIG. 6 shows a transmitter capsule and transmitter holder, and associated components, according to an exemplary embodiment;

FIG. 7 is a cross-sectional view of trigger module according to an exemplary embodiment;

FIG. 8 shows a trigger module switch according to an exemplary embodiment; and

FIG. 9 shows a trigger module control unit according to an exemplary embodiment.

Various features, aspects, and advantages of the exemplary embodiments will become more apparent from the following detailed description, along with the accompanying drawings in which like numerals represent like components throughout the figures and detailed description. The various described features are not necessarily drawn to scale in the drawings but are drawn to emphasize specific features relevant to some embodiments.

The headings used herein are for organizational purposes only and are not meant to limit the scope of the disclosure or the claims. To facilitate understanding, reference numerals have been used, where possible, to designate like elements common to the figures.

DETAILED DESCRIPTION

Reference will now be made in detail to various exemplary embodiments. Each example is provided by way of explanation and is not meant as a limitation and does not constitute a definition of all possible embodiments. It is understood that reference to a particular “exemplary embodiment” of, e.g., a structure, assembly, component, configuration, method, etc. includes exemplary embodiments of, e.g., the associated features, subcomponents, method steps, etc. forming a part of the “exemplary embodiment”. For purposes of this disclosure, the phrases “device(s),” “system(s),” and “method(s)” may be used either individually or in any combination referring without limitation to disclosed components, grouping, arrangements, steps, functions, or processes.

An exemplary embodiment of a logging drone with wiper plug 200 (“drone”) according to the disclosure is shown in FIG. 2. For purposes of this disclosure, a “drone” is a self-contained, autonomous or semi-autonomous vehicle for downhole delivery of one or more wellbore tools. For example, the exemplary drone 200 may be a tool-string which can be pumped downhole with the wellbore fluid, without conventional conveyance methods such as a wireline, e-line, coiled tubing or e-coil, or communicative connections with the surface of the wellbore.

In the exemplary embodiment shown in FIG. 2, the drone 200 includes, among other things, a wiper plug 210 at a downstream end 211 of the drone 200, a perforating gun string 220 which may include one or more perforating guns, including shaped charges 221, connected to the wiper plug 210, for perforating the wellbore casing, cement, and/or surrounding hydrocarbon formation, and a programmable trigger module 230 connected to the perforating gun string 220 and capable of, among other things, initiating each of the one or more perforating guns in the perforating gun string 220 as per a programming sequence input at the surface of the wellbore (before the drone 200 is deployed into the wellbore). It is understood that the programmable trigger module 230 may include an electronic trigger circuit and power supply or other programmable or otherwise control-capable component for carrying out the programmed operations, e.g., initiating the one or more perforating guns according to the programming sequence. For purposes of this disclosure, “downstream” means further into the wellbore towards the toe of the wellbore, and “upstream” means further towards the surface of the wellbore.

Continuing with reference to FIG. 2, a logging tool 240 including, without limitation, one or more sensors to record the depth of the drone 200 and log the structural layout of the wellbore is connected to the trigger module 230 component/section of the tool-string (or, the perforating gun string 220 to the extent that the trigger module 230 may be integrated with the perforating gun string 220 assembly). A transmitter capsule or module 250 which can be separated from the drone 200 and pumped back to surface or retrieved back to the surface by other means is connected to and in electrical data communication with the logging tool 240 and associated componentry. For purposes of this disclosure, “electrical data communication” includes wireless communication such as, without limitation, radio-frequency and Bluetooth communication. While the transmitter module 250 is shown as being connected to the upstream end 212 of the drone 200 tool-string, it is contemplated that the transmitter module 250 may be circumferentially disposed about the logging tool 240, perforating gun string 220 or any other tool or component of the drone 200.

The drone 200 may be deployed downhole after the cement slurry has been pumped into the wellbore. The logging tool 240 component/section of the tool-string logs and records magnetic markers, beacons, casing couplings and other properties in the cased wellbore as the drone 200 is conveyed downhole. In an aspect, the exemplary drone 200 may be configured as a logging drone on which a logging device is the only component. The logging drone may be sent down the wellbore after position markers have been deployed/set in the wellbore or wellbore casing. The logging drone may confirm the placement of the markers that have been set. In an aspect, the logging tool 240 of the drone 200 tool-string or a logging tool as part of a logging drone or other drone tool-string may include a wireless transmitter to transmit data directly back to a receiver at the surface of the wellbore.

With continuing reference to FIG. 2 and the exemplary embodiment, logging data is stored in the transmitter module 250. The wiper plug 210 is positioned at the downstream end 211 of the drone 200 and the drone 200 is forced downhole by pumping with fluid. The downward motion of the wiper plug 210 pushes remaining cement slurry out of the open wellbore casing 120 at the toe end 111 of the wellbore and forces the cement slurry into the annulus 121 between the wellbore casing 120 and hydrocarbon formation 130. The wiper plug 210 may also separate the pump fluid from the cement by its design, as discussed below. The cement 140 in the annulus 121 is then allowed to set and thereby seal the annulus 121. Once the cement 140 is set, the one or more perforating guns in the gun string 220 are initiated by the trigger module 230 via the pre-programmed imitating sequence which is set at surface prior to deployment.

After the detonation of the perforating gun(s) in the perforating gun string 220 has been confirmed by the trigger module 230, the transmitter capsule 250 is separated from the rest of the drone 200 tool-string either ballistically or by other means, such as mechanical detachment, degradation of connecting materials, and the like, and is pumped back to the surface of the wellbore so the logging data may be retrieved. In another technique, the drone 200 may be positively buoyant to aid in its return to the surface while fluid is being pumped into the wellbore. The perforated section(s) of the wellbore toe end 111 allow further pump-down operations to take place because the wellbore fluid within the wellbore casing 120 is hydraulically connected to the hydrocarbon formation 130 by the perforations created through the wellbore casing 120 and dried cement 140 in the annulus 121.

With reference now to FIG. 3, an exemplary wiper plug 210 is shown. The exemplary wiper plug 210 includes a downstream head portion 310 that will be furthest downstream when the drone 200 is deployed in the wellbore. A connecting portion 330 is opposite and upstream from the head portion 310. The connecting portion 300 is configured for connecting to a wellbore tool or drone 200 tool-string component such as a perforating gun of the perforating gun string 220 in the exemplary embodiment shown in FIG. 2. The connection between the perforating gun string 220 and the wiper plug 210 may be, without limitation, a threaded connection, or in certain embodiments the wiper plug 210 may be formed integrally (i.e., as a single piece) with, e.g., a perforating gun housing in the perforating gun string 220. Other connections between the wiper plug 210 and the perforating gun string 220 and generally between the various components of the drone 200 tool-string may be any known connection or technique consistent with this disclosure.

The wiper plug 210 may include, e.g., fins 320 extending radially outwardly for collecting and pushing the cement slurry and separating the cement slurry from the wellbore fluid. The fins 320 also aid in cleaning the inner surface of the wellbore casing 120 by scraping off cement slurry (and potentially other materials) that have collected on the wellbore casing 120. Other components of the exemplary wiper plug 210 shown in FIG. 3 are well known and may include, for example, a through-bore 201 for accomondating a hydraulic or electrical connection through the wiper plug 210, a box (female) connection 202 for, e.g., accommodating cross-over handware, one or more vertical bores 203 for enabling the wiper plug 210 to be pressure balanced with the well-bore pressure, a port 204 and an adapter 205 for accommodating a diaphragm or rupture unit (not shown) for allowing the cement slurry to pass through after the wiper plug 210 reaches a landing position.

With reference now to FIG. 4, an exemplary embodiment of a drone 200 may include a ballistic release tool 260 including a transmitter holder 262 in which the transmitter capsule 250 is held, and a release tool housing 264 connected to each of the transmitter holder 262 and the logging tool 240. The ballistic release tool 260, according to the exemplary embodiments, detachably connects the transmitter capsule 250 to the drone 200, as discussed further below. According to an exemplary method, the logging tool 240 transmits data to the transmitter capsule 250 and the transmitter holder 262, including the transmitter capsule 250, detaches from the drone 200 and travels to the wellbore surface 110 (via buoyancy, pumping, or other known consistent techniques) for retrieval and data collection. An illustrative ballistic release tool including functional aspects is described in U.S. Patent Publication No. 2019/0330947 published Oct. 31, 2019 and commonly owned by DynaEnergetics Europe GmbH, the contents of which are, to the extent such contents are not inconsistent with this disclosure, incorporated herein by reference. The exemplary ballistic release tool 260 is configured for operation with an autonomous drone as discussed throughout this disclosure. For example, the exemplary ballistic release tool 260 does not require a wired connection to a power supply or control device at the surface 110 of the wellbore 101.

The release tool housing 264 may connect to the logging tool 240 by, for example and without limitation, a male threaded connection end 265 that is received in a complementary female threaded connection portion (not shown) of the logging tool 240. In other embodiments, the connection between the release tool housing 264 and the logging tool 240 may be by known consistent techniques including set screws, latches or other mechanical locking, and the like. In still further embodiments, the logging tool 240 may be formed integrally with the release tool housing 264, or the logging componentry, such as, without limitation, circuits and controllers, sensors, transmitters, and other logging componentry as known in the art, may be housed within a portion of the release tool housing 264 adapted to house the componentry. In still other embodiments, the connection between the release tool housing 264 and the logging tool 240 may be indirect, for example via an adapter. Generally, logging devices are functionally well known and the configuration of the logging tool 240 and/or associated componentry for incorporation in the exemplary embodiments of a drone 200, as discussed throughout this disclosure, may take any form consistent with, e.g., making the connections and/or housing the componentry in the drone 200.

With additional reference to FIG. 5 and FIG. 6, according to an exemplary embodiment, each of the transmitter holder 262 and the release tool housing 264 encloses an inner chamber. The transmitter holder 262 is configured to connect to the transmitter capsule 250 by, for example, a threaded connection 267 within the inner chamber. The transmitter capsule 250 may generally be configured in any manner consistent with this disclosure, including, e.g., connecting or being secured to the transmitter holder 262 and housing necessary componentry such as a power source, electronic transmitter/receiver, memory, controller, and/or other componentry as well known. In other embodiments, the transmitter capsule 250 may be formed integrally with the transmitter holder 262, or the associated componentry may be housed in the transmitter holder 262 and the transmitter holder 262 may be configured to house the componentry.

The transmitter holder 262 and the release tool housing 264, according to the exemplary embodiments shown in FIG. 5 and FIG. 6, may be connected to one another by a connecting means such as a connecting sleeve 263. According to an aspect, the connecting means may include threaded connections 266 or other known consistent coupling mechanisms. As discussed further below, the connecting sleeve 263 may be designed to be rigidly connected, e.g., through the threaded connection 266, to one of the transmitter holder 262 or the release tool housing 264 and releasably connected to the other of the transmitter holder 262 or the release tool housing 264. Under such circumstances, release of the releasable connection results in disconnection of the transmitter holder 262 from the release tool housing 264.

In an exemplary embodiment, release by the connecting sleeve 263 may be deliberately caused by an explosive force from a detonator 274. It is contemplated that the detonator 274 may be a wired detonator or a wireless detonator. Thus, separation of the transmitter holder 262 from the release tool housing 264 may be initiated by detonating the detonator 274. According to the exemplary embodiment shown in FIG. 5, a detonator housing 270 is connected at one end to the transmitter holder 262, via a threaded connection 271 within the inner chamber of the transmitter holder 262, and extends upward into the inner chamber of the release tool housing 264. The detonator housing 270 includes a cylindrical center bore 273 primarily occupied by the detonator 274 contained in a detonator sleeve 272. A bushing 275 may be screwed in or otherwise connected to the upper end of the center bore 273 and may help maintain the position and stability of the detonator 274 and reliable electrical contacts thereto, as discussed further below. According to an aspect, the bushing 275 is composed of an insulating or insulative material.

According to the exemplary embodiment shown in FIG. 5, the detonator 274 includes a detonator head 276, a detonator shell 277, an electrical circuit board 278 and an explosive load 279. The detonator head 276 has electrical contacts 280, 281 for contacting a line-in 282 and a line-out 283. The line-in electrical contact 280 and the circuit board 278 are configured for receiving an ignition signal from the line-in 282. In an exemplary embodiment, the line-in 282 may be in electrical communication with, and transmit the ignition signal from, the logging tool 240, via a conductive pin 290 in electrical contact with, e.g., a signal contact of a control circuit in the logging tool 240, and a conductive spring 291 biasing the conductive pin 290 for the electrical contact. The logging tool control circuit may be programmed for outputting the ignition signal, via the signal contact, in response to, without limitation, a completed data collection cycle, a depth of the drone 200 within the wellbore 101, an elapsed time after deployment or passing a marker in the wellbore, and the like. In response to receiving the ignition signal via the line-in electrical contact 280, the circuit board 278 may, according to an aspect, send an electrical signal to a fuse head that ignites and detonates the explosive load 279 according to known techniques. The detonation generates an explosive force, as discussed further below.

The line-out 283 may be, e.g., a conductor rod electrically connected, at a first end, to the line-out electrical contact 281 of the detonator head 276, and, at a second end, to a terminal contact 292. To the extent that the conductor rod 283 needs to pass through any structural element, such as the detonator housing 270, in order to connect to the line-out electrical contact 281 and the terminal contact 292, a channel may be provided through that structural element. According to the exemplary embodiment shown in FIG. 5, the terminal contact 292 is provided within a complementary portion of the inner chamber of the transmitter holder 262 including an insulator 293. A connector receptacle 294 is formed in the terminal contact 292. The transmitter module 250 includes a communication pin 295 extending from the transmitter module 250 and configured for being received within the connector receptacle 294 and thereby in electrical contact with the terminal contact 292. According to an aspect, the conductor rod 283 may transmit data from the logging tool 240 to the transmitter module 250, via the terminal contact 292 and communication pin 295. The conductor rod 283 may relay the data from the line-out electrical contact 281 of the detonator head 276. For example, when the line-in electrical contact 280 receives a signal that is not the ignition signal, the signal is passed to the line-out electrical contact 281 for transmission via the conductor rod 283. Thus, signals carrying logging data may be communicated from the signal contact of the logging tool control circuit to the transmitter module 250.

With further reference to the exemplary embodiments shown in FIG. 5 and FIG. 6, a plurality of tubing fingers 300 extend from the transmitter holder 262. According to an aspect, a space, groove or channel 302 is between each tubing finger 300. Each tubing finger 300 continues to form into a tip, protrusion or flange 304 at the upper end of the transmitter holder 262. The space 302 between tubing fingers 300 allows each finger 300 to deflect radially inward and outward when subjected to a radial force, particularly to a radial force exerted on the flange 304 thereof. When fingers 300 are subjected to an outward radial force, flanges 304 are adapted to be received within one or a plurality of compatible receiving grooves or recesses 306 in an inner wall of the release tool housing 264. The flanges 304 and receiving groove 306 permit a tightening engagement between the transmitter holder 262 and the release tool housing 264.

According to an aspect, a latch 308 is circumferentially mounted on the external surface of the detonator housing 270. The latch 308 may be substantially cylindrical. According to an exemplary embodiment, one or a plurality of shear pins 309 extend through the annular wall of latch 308 and engage pin channels (not shown) in the detonator housing 270 and function to prevent unintentional movement of the latch 308 relative to the detonator housing 270. For example, the shear pins 309 prevent the latch 308 from shifting axially along the outer surface of the detonator housing 270. Thus, once the latch 308 is properly placed on the detonator housing 270, the shear pins 309 will hold the latch 308 in place relative to the detonator housing 270.

According to the exemplary embodiments shown in FIG. 5 and FIG. 6, the latch 308 is mounted onto the external surface of the detonator housing 270 and the detonator housing 270 is inserted into the inner chamber of release tool housing 264. As the detonator housing 270 is inserted through the inner chamber of the release tool housing 264 and connected to the transmitter holder 262, an outer surface of the latch 308 slides under the flanges 304 of the tubing fingers 300 and exerts a radially outward force on the flanges 304 of the tubing fingers 300. When the detonator housing 270 is fully connected with (e.g., threaded into) the transmitter holder 262, the latch 308 is thereby lodged under the flanges 304 and causes the flanges 304 to be disposed in the receiving grooves or recesses 306.

In addition, when the detonator housing 270 is fully connected to the transmitter holder 262, the latch 308 lodged under the flanges 304 causes undersides 310 of the flanges 304 to each engage a top surface 312 of the connecting sleeve 263. Engagement of the flange undersides 310 with the top surface 312 of the connecting sleeve 312 will prevent the connecting sleeve 263 from disengaging from the tool transmitter holder 262. Removal of the outward radial forces on the fingers 300 by the latch 308 will result in the flange undersides 310 disengaging from the top surface 312 of the connecting sleeve 263. A certain amount of axial force acting to pull the transmitter holder 262 and the release tool housing 264 away from each other when the undersides 310 of the flanges 304 are not engaged with the top surface 312 of the connecting sleeve 263 will result in disconnection of the transmitter holder 262 and the release tool housing 264. In the exemplary embodiments shown in FIG. 5 and FIG. 6, the release tool housing 264 is connected to the connecting sleeve 263 by the threaded connection 266. Thus, disengagement of the flanges 304 from the connecting sleeve 263 results in the transmitter holder 262 and the connecting sleeve 263 disengaging from the release tool housing 264.

With continued reference to FIG. 5, a central vent 315 in the lower portion of the detonator housing 270 extends downward from the center bore 273. One or more radial vent(s) 316 extend radially from the central vent 315 to the exterior of the detonator housing 270. Each of the radial vents 316 exits the detonator housing 270 at a vent port 318 into an expansion chamber 320 bounded by an external surface of the detonator housing 270 and an internal surface of the connecting sleeve 263, and/or an internal surface of the release tool housing 264.

Upon detonation of detonator 274, rapidly expanding gases fill the radial vents 316 and the expansion chamber 320. Proper sealing of the expansion chamber 320, e.g., by various o-rings 325, results in the expanding gases building pressure within the expansion chamber 320. This pressure builds as the explosive load 279 and/or another energetic material in the detonator 274 continues to burn, exerting an increasing axial force on the latch 308, in a direction away from the transmitter holder 262. The amount of energetic material, e.g., volume of the explosive load 279, is selected such that the axial force exerted on the latch 308 exceeds the force necessary to shear the shear pin(s) 309. Once the shear pin(s) 309 are sheared, the latch 308 is able to move axially away from the transmitter holder 262. This axial movement of the latch 308 will result in the latch 308 no longer exerting an outward radial force on the fingers 300, and the flanges 304 will disengage from the connecting sleeve 263 and the recesses 306. The axial force will likewise detach the transmitter holder 262, including the transmitter module 250, from the release tool housing 264, allowing the transmitter module 250 to be retrieved at the surface 110 of the wellbore 101 according to known techniques for, e.g., retrieving wellbore tools that have been returned from within the wellbore.

A ballistic release tool for use with the exemplary embodiments of a drone 200 as discussed throughout this disclosure is not limited to the exemplary embodiments shown in FIG. 5 and/or FIG. 6. Other known ballistic release tools, mechanisms, techniques, etc. consistent with this disclosure may be incorporated for ballistically detaching a transmitter capsule, according to the exemplary embodiments.

With reference now to FIG. 7, and continuing reference to FIG. 4, a trigger module 230 according to an exemplary embodiment includes, without limitation, a top housing 402 connected to a bottom housing 404. According to the exemplary embodiments shown in FIG. 4 and FIG. 7, the bottom housing 404 may include a male threading 406 for directly coupling with, e.g., a complementary female threading (such as female threading 224) on a gun housing 222 of a perforating gun in the perforating gun string 220. While a single perforating gun is shown, e.g., in FIG. 2 and FIG. 4, according to the exemplary embodiments, it is understood that the perforating gun string 220 may include a plurality of perforating guns connected in series. Accordingly, it is also understood that, as in the exemplary embodiments shown in FIG. 4 and FIG. 7, the male threading 406 on the trigger module 230 connects to female threading on the gun housing of the furthest upstream perforating gun, while female threading 224 on the furthest downstream perforating gun connects to a male threading end 215 of the wiper plug 210. In various embodiments, a cross-over sub or other hardware (not shown) may be positioned between and connect the furthest downstream perforating gun 220 and the wiper plug 210. Such connection generally may take any form and include any known consistent components and/or configurations.

In other embodiments, the trigger module 230, the perforating gun/perforating gun string 220, and the wiper plug 210 may variously connect by any known consistent techniques including, without limitation, cross-over subs, latches, mechanical locking mechanisms, set screws, and the like. In still other embodiments, two or all of the trigger module 230, a perforating gun (i.e., furthest upstream or furthest downstream), and the wiper plug 210 may be formed integrally.

Generally, any tools or components included in a drone 200 as described throughout this disclosure may be configured, connected, and/or assembled in any manner consistent with the disclosure, including, e.g., making connections and/or housing componentry in the drone 200.

Within continuing reference to FIG. 7, the top housing 402 may be dimensionally configured for connecting with the logging tool 240. For example, the top housing 402 may include female threading 403 within a cavity 405 of the top housing 402. The cavity 405 and female threading 403 may respectively receive and connect to a male threaded projection 241 on the logging tool 240. According to the exemplary embodiment, the trigger module 230 includes a frame 410 configured to mount a circuit board 415. The circuit board 415 may include a logic circuit 420 (FIG. 9). A switch 430 supplies power to the logic circuit 420, via a first electrical contact 431 (FIG. 8) operably coupled (dashed line) to a power source 440 and a second electrical contact 432 operably coupled (dashed lined) to the logic circuit 420, as further shown and described with respect to FIG. 9. The power source 440 in the form of, without limitation, a battery pack, may be mounted on a lower side of the frame 410, although not shown in FIG. 7. The power source 440 may be battery such as a lithium ion battery or another electrical power storage device. The power source 440 may be mounted on the circuit board 415 or separately mounted within the trigger module 230.

The trigger module 230 may be in electrical communication with the logging tool 240. For example, the trigger module 230 may include one or more signal receivers 407 for receiving electrical signals from the logging tool 240. The logging tool control circuit (as previously discussed) may output electrical signals regarding, e.g., a depth, orientation, or position of the drone 200, i.e., relative to a marker, within the wellbore 101. One or more electrical connections (not shown) such as, without limitation, cables, wires, contacts, and the like, may be positioned within a respective channel 408 adjacent to each signal receiver 407. In an aspect, one or more of the signal receivers 407 may be replaced by a signal transmitter to enable two-way communication between the logging tool 240 and the trigger module 230.

The signal receiver 407 (for purposes of this disclosure, “the signal receiver 407” is used for brevity but understood to describe each of a plurality of signal receivers 407 and/or one or more transmitters, unless otherwise specified) may be operably coupled to the logic circuit 420 via cables (not shown) or other suitable connection. The signal receiver 407 may be powered via the logic circuit 420 once the switch 430 is closed. Alternatively, the signal receiver 407 may be provided with its own power supply. The signal receiver 407 may be configured to relay an electrical signal, e.g., from the logging tool 240, to the logic circuit 420. The logic circuit 420 may be configured to output an operation signal for, without limitation, controlling each perforating gun in the perforating gun string 220. The operation signal may be based on, e.g., the electrical signal from the logging tool 240 and/or an input signal from another component, such as a sensor, timing circuit, and the like. Such components may be part of the trigger module 230 but may generally be located anywhere from which communication with the logic circuit 420, including wireless communication (i.e., radio-frequency, Bluetooth, etc.), is enabled.

With reference to FIG. 8, an exemplary embodiment of the switch 430 is shown. The switch 430 may include the first electrical contact 431 operably coupled to the power source 440, the second electrical contact 432 operably coupled to the logic circuit 420, and a third electrical contact 433. In an aspect, the power source 440 and the logic circuit 420 may be de-coupled or open-circuited unless both the first electrical contact 431 and the second electrical contact 432 are contacted by the third electrical contact 433. The third electrical contact 433 may be mounted on a second circuit board 434, which may be mounted on a backing disk 435 for mechanical support. The second circuit board 434 and the backing disk 435 may be mounted on a piston 492 (FIG. 7) via a screw 436 inserted into a hole 493 provided in an end of the piston 492. When the piston 492 pushes the third electrical contact 433 into contact with the first electrical contact 431 and the second electrical contact 432, thereby closing the switch 430, power is supplied from the power source 440 to the logic circuit 420.

With reference now to FIG. 9, an exemplary embodiment of a control unit 450 is shown. In the exemplary embodiment, a source 480 such as the logging tool control circuit may output an electrical signal based on a threshold condition (pressure value or corresponding depth in the well) required before powering and arming the trigger module 230, i.e., the logic circuit 420. For example, the signal may be based on the drone 200 reaching a particular depth or position within the wellbore 101. The switch 430 may include circuitry configured to receive and process the output signal and close the switch 430 in response to the threshold condition being satisfied, according to the output signal. Closing the switch 430 supplies power from the power source 440 to the logic circuit 420, thereby “arming” the trigger module 230.

In further aspects, the control unit 450 may include one or more of a first environment sensor 481 operably coupled to a first microcontroller 485 and a second environment sensor 482 operably coupled to a second microcontroller 486. The first environment sensor 481 may be configured to detect a first environment condition and output a first environment signal based on the first environment condition. The second environment sensor 482 may be configured to detect the first environment condition and output a second environment signal based on the first environment condition. The combination of the first environment sensor 481 and the second environment sensor 482 may allow for independent measurement and verification of the first environment condition. The first environment condition may be, without limitation, a temperature of the wellbore environment, vibrations in the wellbore environment, or a pressure of the wellbore environment. The first environment condition may relate to a threshold requirement for outputting an operation signal, such as a detonation command, to the perforating gun string 220, via an output terminal 487. Additional sensors 483, 484 may be respectively connected to the first microcontroller 485 and the second microcontroller 486, and configured for, e.g., confirming the threshold condition measured by the source 480, such as the depth or position of the drone 200 as determined by the logging tool 240. The sensors 483, 484 may also measure one or more other conditions, according to particular applications.

With additional reference back to FIG. 7, the trigger module 230/control unit 450 may include an output terminal 487 operably coupled to the logic circuit 420. The furthest upstream perforating gun in the perforating gun string 220 may be operably coupled to the output terminal 487. Accordingly, upon a satisfaction of any threshold requirements for triggering perforating gun(s), the operation signal output by the logic circuit 420 may be transmitted to the furthest upstream perforating gun in the perforating gun string 220, via the output terminal 487. The additional perforating guns in the perforating gun string 220 may be operably coupled with the furthest upstream perforating gun, via through lines and/or switches such that any operation signal received by the furthest upstream perforating gun may be passed through and selectively received by any of the perforating guns. For example, each perforating gun may have a unique detonation command such that sequential operation signals output from the logic circuit 420 may respectively initiate firing of individual perforating guns. The sequential operation signals may be based on separate threshold conditions or may be a preprogrammed sequence.

In other embodiments of a drone 200 according to this disclosure, the drone 200 may include other wellbore tools, such as plugs, cutters, and the like, and the trigger circuit 230 may be used to initiate such other wellbore tools with a corresponding operation signal output by the logic circuit 420. The other wellbore tools may each include control circuitry configured to selectively initiate in response to the operation signal received by the wellbore tools. In the case of the perforating gun string 220, for example, the control circuitry may be an electronic initiation circuit as described in U.S. Pat. No. 9,915,513 issued Mar. 13, 2018, which is commonly owned by DynaEnergetics Europe GmbH, the contents of which are incorporated herein by reference, to the extent that such contents are not inconsistent with this disclosure.

While the trigger module 230 has been described according to the exemplary embodiments as shown, e.g., in FIGS. 2, 4, and 7-9, the trigger module 230 generally may take any form consistent with, e.g., making the connections and/or housing associated componentry in the drone 200. Associated componentry may include, without limitation, a power source, an electronic controller, one or more sensors and/or connections to output signals from other components of the drone 200, and the like.

In an exemplary method of operation of an exemplary drone according to the embodiments discussed throughout this disclosure, the method may include pumping cement down a wellbore casing of a wellbore, to fill a toe portion of the wellbore and an annulus between the wellbore casing and a hydrocarbon formation surrounding the wellbore, to isolate wellbore fluids and other contents within the wellbore casing from the hydrocarbon formation. The method may further include deploying the drone downhole, i.e., into the wellbore via the wellbore casing. The method may also include pushing cement within the wellbore casing downward with a wiper plug of the drone, as the drone travels downhole in the wellbore casing. The step of pushing the cement downward with the wiper plug may include pushing the cement around open areas surrounding the wellbore casing and/or cleaning an inner surface of the wellbore casing.

Still further, the method may further include collecting, with a logging tool of the drone, information (i.e., data) regarding the wellbore, as the drone travels downhole. In an aspect, the method may include sending the data from the logging tool to a transmitter capsule of the drone and/or storing the data in the transmitter capsule. In another aspect, the method may include wirelessly transmitting the data from the transmitter capsule to a receiver at a surface of the wellbore. The method may further include detaching the transmitter capsule from the drone and returning the transmitter capsule to the surface. In an aspect, the step of detaching the transmitter capsule may include detaching the logging tool and the transmitter capsule, e.g., for drone embodiments in which the logging tool and the transmitter capsule are directly connected. In another aspect, the step of detaching the transmitter capsule may include, without limitation, degrading a frangible or disintegrable connection and/or actuating a releasable mechanical connection between the transmitter capsule and the drone, and the like. In a further aspect, the step of detaching the drone may include separating the transmitter capsule from the drone with a ballistic release tool of the drone.

Further, the method may include returning the transmitter capsule to the wellbore surface. In various aspects, the step of returning the transmitter capsule to the wellbore surface may include pumping the transmitter capsule to the surface or providing a buoyant transmitter capsule (and/or drone) that will float to the surface. The method may further include retrieving the transmitter capsule at the surface.

The method may further include perforating, with a perforating gun or string of perforating guns of the drone, the cemented section(s) of the wellbore. In an aspect, the step of perforating may be performed in response to a detonation command received at each individual perforating gun. In another aspect, perforating may provide additional surface area for flushing the wellbore.

The exemplary method is not limited by the number, type, or order in which the method steps are set forth above. In various embodiments, the method may proceed in any manner consistent with a drone according to the exemplary embodiments discussed throughout this disclosure and/or other embodiments consistent with this disclosure. Further, the method may proceed in any manner required by and consistent with wellbore operations and/or particular applications in which the drone is used. For example and without limitation, the step of detaching the transmitter capsule may occur at any desired time based on, e.g., the amount of data desired, and/or the step of perforating the cemented sections may occur after the step of detaching the transmitter capsule.

This disclosure, in various embodiments, configurations and aspects, includes components, methods, processes, systems, and/or apparatuses as depicted and described herein, including various embodiments, sub-combinations, and subsets thereof. This disclosure contemplates, in various embodiments, configurations and aspects, the actual or optional use or inclusion of, e.g., components or processes as may be well-known or understood in the art and consistent with this disclosure though not depicted and/or described herein.

The phrases “at least one”, “one or more”, and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.

In this specification and the claims that follow, reference will be made to a number of terms that have the following meanings. The terms “a” (or “an”) and “the” refer to one or more of that entity, thereby including plural referents unless the context clearly dictates otherwise. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. Furthermore, references to “one embodiment”, “some embodiments”, “an embodiment” and the like are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term such as “about” is not to be limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Terms such as “first,” “second,” “upper,” “lower” etc. are used to identify one element from another, and unless otherwise specified are not meant to refer to a particular order or number of elements.

As used herein, the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of “may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances the modified term may sometimes not be appropriate, capable, or suitable. For example, in some circumstances an event or capacity can be expected, while in other circumstances the event or capacity cannot occur—this distinction is captured by the terms “may” and “may be.”

As used in the claims, the word “comprises” and its grammatical variants logically also subtend and include phrases of varying and differing extent such as for example, but not limited thereto, “consisting essentially of” and “consisting of.” Where necessary, ranges have been supplied, and those ranges are inclusive of all sub-ranges therebetween. It is to be expected that the appended claims should cover variations in the ranges except where this disclosure makes clear the use of a particular range in certain embodiments.

The terms “determine”, “calculate” and “compute,” and variations thereof, as used herein, are used interchangeably and include any type of methodology, process, mathematical operation or technique.

This disclosure is presented for purposes of illustration and description. This disclosure is not limited to the form or forms disclosed herein. In the Detailed Description of this disclosure, for example, various features of some exemplary embodiments are grouped together to representatively describe those and other contemplated embodiments, configurations, and aspects, to the extent that including in this disclosure a description of every potential embodiment, variant, and combination of features is not feasible. Thus, the features of the disclosed embodiments, configurations, and aspects may be combined in alternate embodiments, configurations, and aspects not expressly discussed above. For example, the features recited in the following claims lie in less than all features of a single disclosed embodiment, configuration, or aspect. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.

Advances in science and technology may provide variations that are not necessarily express in the terminology of this disclosure although the claims would not necessarily exclude these variations.

Claims

1. An autonomous logging drone tool-string, comprising: a wiper plug at a downstream end of the logging drone tool-string;a logging tool; anda transmitter capsule in electrical communication with the logging tool, wherein the transmitter capsule is configured for detaching from the logging drone tool-string.

2. The autonomous logging drone tool-string of claim 1, wherein the transmitter is configured for ballistically detaching from the logging drone tool-string.

3. The autonomous logging drone tool-string of claim 1, wherein the transmitter capsule is configured for storing logging data after detaching from the logging drone tool string.

4. The autonomous logging drone tool-string of claim 1, further comprising a perforating gun positioned between the wiper plug and the logging tool.

5. The autonomous logging drone tool-string of claim 4, further comprising a trigger module configured for outputting a detonation command to the perforating gun.

6. The autonomous logging drone tool-string of claim 5, wherein the perforating gun is one of a plurality of perforating guns in a perforating gun string, wherein the trigger module is configured for outputting a detonation command for each of the plurality of perforating guns.

7. The autonomous logging drone tool-string of claim 5, wherein the trigger module is in electrical communication with the logging tool.

8. The autonomous logging drone tool-string of claim 5, wherein the trigger module includes a power source and a logic circuit, wherein the logic circuit is programmed for outputting the detonation command.

9. The autonomous logging drone tool-string of claim 8, wherein the trigger module further includes an electrical switch between the power source and the logic circuit, wherein the switch is operable for changing from an open state to a closed state, and the switch in the closed state supplies power from the power source to the logic circuit.

10. The autonomous logging drone tool-string of claim 9, wherein the switch is operable for changing from an open state to a closed state in response to an electrical signal corresponding to a threshold condition, wherein the threshold condition is one of an environment condition, a depth, a position, and an orientation, within a wellbore.

11. The autonomous logging drone tool-string of claim 1, wherein the transmitter capsule is configured for wirelessly transmitting logging data to a receiver.

12. The autonomous logging drone tool-string of claim 11, wherein the receiver is positioned at a surface of a wellbore.

13. An autonomous logging drone, comprising: a wiper plug;a perforating gun;a trigger module;a logging tool; anda transmitter capsule, wherein each of the wiper plug, the perforating gun, the trigger module, the logging tool, and the transmitter capsule are connected as a tool-string, and the wiper plug is positioned at a downstream end of the tool-string.

14. The autonomous logging drone of claim 13, wherein the logging tool and the transmitter capsule are integrally formed.

15. The autonomous logging drone of claim 13, wherein the transmitter capsule is configured for detaching from the tool string.

16. The autonomous logging drone of claim 13, wherein the transmitter capsule is positioned at an upstream end of the tool-string.

17. The autonomous logging drone of claim 13, further comprising a ballistic release tool connected as a part of the tool-string, wherein the ballistic release tool is connected to the transmitter capsule and configured for detaching the transmitter capsule from the tool-string.

18. A method for cementing a wellbore and logging wellbore information, comprising: pumping cement down a wellbore casing within the wellbore;deploying a logging drone into the wellbore casing, wherein the logging drone includes a wiper plug at a downstream end, a logging tool positioned upstream of the wiper plug, and a transmitter capsule, wherein the transmitter capsule is in electrical communication with the logging tool;pumping the logging drone down the wellbore casing with a wellbore fluid;pushing cement out of the wellbore casing with the wiper plug and collecting wellbore information with the logging tool;storing the wellbore information in the transmitter capsule; andretrieving the wellbore information from the transmitter capsule.

19. The method of claim 18, further comprising detaching the transmitter capsule from the logging drone.

20. The method of claim 19, further comprising pumping the transmitter capsule to a surface of the wellbore; and retrieving the transmitter capsule at the surface of the wellbore.