GB2605807A

GB2605807A - Downhole test method and associated apparatus

Info

Publication number: GB2605807A
Application number: GB2105271.7A
Authority: GB
Inventors: Michael Larkins Bronson
Original assignee: Wellvene Ltd
Current assignee: Wellvene Ltd
Priority date: 2021-04-13
Filing date: 2021-04-13
Publication date: 2022-10-19
Also published as: GB202105271D0

Abstract

Checking a lock dog cavity is suitable for receiving a lock dog by running a test tool 20 into a wellbore prior to an operation in the wellbore. A lock dog cavity 6 is checked to verify suitability of the lock dog cavity for receiving a lock dog. The downhole log dog cavity test tool may comprise test dogs 22 which are temporarily extended into the lock dog cavity.

Description

DOWNHOLE TEST METHOD AND ASSOCIATED APPARATUS

TECHNICAL FIELD

The present invention relates to a method of testing a portion of a wellbore, particularly, but not exclusively, a landing portion thereof; and associated apparatus.

BACKGROUND

Wel!bores for accessing oil/gas reservoirs are typically completed with lining or casing providing an inner bore, ultimately for the passage of hydrocarbon fluids from the reservoir for production. Various downhole components can be installed or deployed in wellbores, typically to assist in production, such as in differing phases. Landing nipples are downhole components, provided as a short section of heavy wall tubular with a machined internal surface with a seal area and a locking profile. Landing nipples are often included in completions at regular intervals along the wellbore to allow the installation of flow-control devices, such as plugs and chokes.

Common types of landing nipples include No-Go nipples, selective-landing nipples and ported safety valve nipples. Landing nipples have a packing bore inner diameter for a particular tubing size and weight, with different specifications depending on whether the tubing is standard weight or heavy weight. Nipples with a range of sizes, thread connections, material compositions, and pressure ratings are available for landing, locking, and sealing locks with subsequently run-in flow control devices in the production tubing. The internal profile of the landing nipples can include a no-go shoulder that receives a no-go of the corresponding lock mandrel, a pocket for receiving lock dogs, and a polished bore. The lock mandrel together with the flow control device are lowered into the tubing until the no-go of the lock engages the no-go shoulder in the nipple. A jarring tool in the string is used to extend the locking dogs into the locking pocket, anchoring the assembly. The lock packs the seals against the nipple's polished bore.

Prior to running in the string with the lock mandrel and flow control device or other component to be set in the wellbore, operators sometimes seek reassurance of the accessibility or location of the landing nipple before running in the string with the lock mandrel. This check is performed with a drift tool, which involves running in an accurately machined device to match the landing nipple profile, often with a no-go similar to that of the lock mandrel to be subsequently run-in (where applicable). The depth of the drift tool when it engages the landing nipple (e.g. no-go/shoulder) is measured, reassuring the operator of access to the landing nipple. The drift tool is typically toleranced for drifting: being machined to a maximum outer diameter corresponding to the drift diameter usually provided as an effective guarantee by tubing/component manufactures of a diameter of tool that can pass through the bore of casing, components, etc. If the drift tool can access and engage the landing nipple, confirmed with a depth measurement corresponding to the known location of the landing nipple, then the operator is reassured that the string with the lock mandrel and flow control device can be deployed and run-in to engage the landing nipple at the desired location -after the drift tool has been pulled to surface.

It may be an object of one or more aspects, examples, embodiments, or claims of the present disclosure to at least mitigate or ameliorate one or more problems associated with the prior art, such as described herein or elsewhere.

SUMMARY

According to an aspect, there is provided a method of testing a portion of a wellbore.

According to an aspect, there is provided a test tool for testing the portion of the wellbore. The method may comprise running the test tool into the wellbore prior to an operation in the wellbore, particularly prior to running a subsequent operation tool into the wellbore in a subsequent run. The method may comprise running in a landing profile test tool. The landing profile test tool may comprise a drift test tool for checking or testing an inner diameter. In at least some examples, the method may comprise testing a downhole landing profile. The method may comprise measuring and/or verifying a location of a landing profile and/or access thereto.

The method may comprise checking or testing a cavity. The cavity may comprise a recess. The recess may comprise an annular recess. The recess may comprise a locking recess. The cavity may comprise a key profile, for receiving a key/dog of a tool.

The cavity may comprise a pocket. The cavity may comprise a lock dog cavity. In at least some examples, the method may comprise checking a lock dog pocket, such as to verify suitability of the lock dog pocket/s for receiving a lock dog/s. The method may comprise testing the cavity. The method may comprise testing the lock dog pocket with a test dog/s. The method may comprise testing the lock dog pocket with the test tool in advance of running in a subsequent tool for locking in the lock dog pocket. The method may comprise only briefly and temporarily extending the test dog/s into the lock dog pocket. The method may comprise retracting the test dogs after extension into the lock dog pocket. The method may comprise only extending the test dogs to test the lock dog pocket. The method may comprise only extending the dogs to test the lock dog pocket and not to lock the tool. Accordingly, the method may comprise extending the lock dogs without locking the test tool in the landing profile. The method may comprise extending the test dogs into the lock dog pocket/s without engaging a sealing bore of the landing profile. In at least some examples, the test tool does not comprise any seal/s. Likewise, in at least some examples, the string comprising the test tool may not comprise any seal/s. The test tool may be run in on slickline, e-line, wireline, coiled tubing, drill -pipe or the like. In at least some examples, the test tool is run in on slickline together with a jarring tool. The method may comprise extending the test dogs with the jarring tool, such as with the jarring tool being activated once the test tool has engaged the landing nipple.

In at least some examples, the method comprises running-in a downhole test tool to perform a test of a landing nipple in advance of running-in a subsequent tool for landing on the landing nipple, the test tool comprising a test dog/s for performing a test of a lock dog pocket associated with the landing nipple. Optionally the method comprises retrieving the test tool to verify success of the test of the lock dog pocket/s.

In at least some examples the method may comprise running-in a test tool to test both the landing nipple and the lock dog pocket. The same test tool may be utilised to perform both the landing nipple test and the lock dog pocket test.

Accordingly the method/s disclosed herein may comprise an improvement on landing nipple checks with a drift or test tool. Once the test tool has engaged or tagged the landing nipple (e.g. as confirmed by passage of the string being halted at a depth corresponding to the known or expected depth or location of the landing nipple), rather than merely retrieve the drift or test tool, the test tool may be used to perform an additional check or test of the viability of a locking recess associated with the landing nipple.

The method may comprise activating the test tool. Activating the test tool may comprise extending the test dog/s. The method may comprise jarring. Additionally, or alternatively, the method may comprise activating the tool with fluid pressure, such as a change in fluid pressure and/or a fluid pressure differential. The test tool may be activated by one or more of: jarring; fluid pressure; fluid pressure differential; weighton-tool; a resilient member; hydraulic; electric signal; a motor; a piston; a valve.

The method may comprise extending the test dog/s using a relative axial movement between portions of the test tool. The tool may comprise an upper portion and a lower portion, the upper portion being movable relative to the lower portion to cause extension and/or retraction of the test dogs. In at least some examples, the test dog/s is/are extended by jarring. The relative axial movement of the tool portions may be achieved or actuated by one or more of: jarring; fluid pressure; fluid pressure differential; weight-on-tool; a resilient member; hydraulic; electric signal; a motor; a piston; a valve.

The method may comprise activating the test dog/s by generating the relative axial movement between the portions of the test tool. The method may comprise extending and/or retracting the test dog/s using a cam member. The method may comprise retracting the test dog/s using a relative axial movement of portions of the test tool. The relative axial movement to retract the test dogs may be a reversal of the axial movement to extend the test dogs. In at least some examples, the test dog/s may be retracted by pulling the test tool. Puling the test-tool may reverse the relative axial movement used to extend the test dog/s. Pulling the tool may axially move the cam member associated with the test dog/s.

The method may comprise testing only a portion of the lock dog recess. For example, the method may comprise only testing a portion of the 3600 of the circumference of an annular locking recess. Alternatively, the method may comprise testing the full 360° of the circumference of the annular locking recess.

The method may comprise adjusting or varying a rotational orientation. The method may comprise adjusting or varying a rotational orientation of the test tool and/or the subsequently-run tool that engages the landing profile. The method may comprise running an indexer to adjust the rotational orientation. The method may comprise sequentially indexing the test dog/s and/or dog/s of the subsequent tool to vary the portion/s of the locking recess engaged or engageable with the test dog/s and/or lock dog/s. The method may comprise indexing the test tool to vary a portion of the circumference of the locking recess engaged or engageable with the test dogs. The method may comprise indexing by an angle different from an angular separation between dogs. For example, where the test tool comprises four dogs regularly spaced at 900 intervals around the circumference of the test tool, then the indexer may index the test tool to align the test dogs with a portion of the locking recess not previously aligned with a test dog prior to indexing. The indexing angle may be an angle that is not a multiple of the angular spacing of the test dogs. For example, where the test dogs are spaced at 900 intervals, then the indexer may cause rotation by angles other than 90°, 1800, 270° or 360°. The rotation may be a fraction of the angular spacing. For example, the indexer may cause sequential rotations of 30° when the angular spacing is 90° The indexer may be indexed to cause rotation when the test dogs or lock dogs are retracted, such as between successive extensions of the test dogs or lock dogs.

Additionally, or alternatively, the indexer may be indexed to cause or attempt rotation when the test dogs or lock dogs are extended. For example, if the test tool is run with an indexer, then the test dogs may be configured to extend to a maximum diameter where there is a clearance between the extended test dogs and the inner diameter of the locking recess. Accordingly the clearance may enable the test dogs to be rotated in the locking recess, provided there is no impediment in the locking recess. Accordingly, the method may comprise sweeping the test dog/s around the locking recess to test whether the entire circumference of the locking recess is free for receiving dogs.

The method may comprise varying or adjusting the rotational orientation of the subsequently-run tool to vary portion/s of the locking recess aligned with the lock dog/s. In at least some examples, the method comprises running the subsequent tool with the indexer to rotate the subsequent tool in case a first or previous attempt/s to extend and engage the lock dog/s is unsuccessful.

The test dog/s may differ from lock dog/s intended to engage the lock dog pocket to lock a subsequent tool to the landing profile. The test dog/s may comprise a dimension different to the lock dog/s. The test dogs may comprise a greater proportion of the circumference than dogs of a tool to be subsequently run. The test dog/s may comprise at least 50% of the circumference. For example, where the test tool comprises a set of three dogs, each dog may constitute at least a 60°, such that the three dogs in total comprise at least 180° of the 360° total circumference. Similarly, where the test tool comprises four dogs, each dog may comprise at least 45°, such that the four dogs in total comprise at least 180° of the 360° total circumference. In at least some examples, the test dogs may comprise a total of 200°, 220°, 240°, 270° respectively. For example, the dogs of a four-dog test tool may each comprise 60° such that the dogs occupy a total of 240° of the 360° total circumference. The dogs may be equally spaced around the circumference. For example, each of the four dogs of the four-dog test tool may be regularly spaced at 90° intervals around the circumference.

In at least some examples, the lock dog/s may be similar to lock dog/s intended to engage the lock dog pocket to lock a subsequent tool to the landing profile. For example, the test dogs may be similar to lock mandrel dogs of a subsequently-run tool (e.g. a lock mandrel). Accordingly, the method of testing may comprise testing the lock dog pocket with lock dog/s similar or identical to lock dog/s intended to engage the lock dog pocket to lock a subsequent tool to the landing profile. Such a test in advance of running the actual tool intended to lock to the landing profile may provide a realistic synthesis of the subsequent use scenario with the subsequently-run tool.

The method may comprise providing an indication of lock dog activation. The method may comprise providing an indication of lock dog activation only after activation of the lock dog/s. The method may comprise providing a positive indication of extension of the lock dog/s only after a successful extension of the lock dog/s. The successful extension of the lock dog/s may comprise the extension of the lock dog to at least a minimum position or extension. For example, successful extension may only be achieved when the lock dog/s has been extended to a diameter corresponding to at least a minimum diameter. The minimum diameter may be greater than an inner diameter in the wellbore at a location elsewhere, such as uphole, of the lock dog pocket. For example, the lock dog pocket may comprise a larger inner diameter than the inner diameter of tubular/s and/or cavity/ies uphole of the lock dog pocket. The method may comprise only indicating a successful deployment of the test dogs when the test dogs have been extended to at least the minimum diameter. Accordingly, the method may comprise preventing indication of extension of the test dogs if the test dogs have been extended at or in a wrong portion of the wellbore. The method may comprise preventing indication of extension of the test dogs if the test dogs have not been extended sufficiently fully in the lock dog pocket. For example, where access to the lock dog pocket is obstructed or impeded, such as by corrosion or debris in the pocket, then the test dogs may not be fully or sufficiently extendable into the lock dog pocket. The indicator may be configured to prevent indication of successful test dog extension when the test dogs have not been fully or sufficiently extended.

The indicator may comprise a visual indicator, such as can be retrospectively checked when the test tool is pulled to surface. The indicator may comprise a tell-tale, providing retrospective indication that the test tool has been in a configuration with the test dogs sufficiently extended to verify viability of the lock dog pocket. The indicator may be activated by the relative axial movement of the portions of the test tool. The indicator may be configured to only be activated once there is sufficient relative axial movement between the portions of the test tool to correspond to a sufficient or at least minimum extension of the test dogs. The indicator may comprise a snap ring. The snap ring may be configured to change axial position in dependence on relative axial movement between the portions of the test tool. The test tool may be configured to axially displace the snap ring to indicate an amount of relative axial movement between the portions of the test tool. In at least some examples, the test tool may comprise predefined locations for the snap ring, such as at least a pair of grooves or annular recesses for receiving the snap ring. A first groove may correspond to the location of the snap ring during run-in and prior to extension of the test dogs. A second groove may correspond to the location of the snap ring after successful extension of the test dogs to the minimum or sufficient extension diameter. The axial separation between the first and second grooves may correspond to the relative axial movement between portions associated with extension of the test dogs to the sufficient minimum diameter. The axial separation may be determined by or at least dependent on a cam geometry associated with extending, and optionally retracting, the test dogs. In at least some examples, the test tool may be configured to provide indication of an absolute extent of test dog extension. The indicator may comprise a tell-tale that indicates a maximum or extreme position of relative axial movement between the portions of the test tool. For example, the test tool may comprise a plurality of locations for receiving the tell-tale snap ring, such as a plurality of grooves: the snap ring remains seated in whichever groove to which it is displaced by the relative axial movement. Upon retrieval of the test tool, the whichever groove the snap ring is located indicates the maximum axial movement that has been achieved by the test tool -corresponding to the maximum extension of the test dogs that has been achieved during that run of the test tool. Likewise, where the tell-tale is a snap ring or similar, the test-tool may be configured to allow the axial position of the snap ring to be undefined in its variation of position (e.g. without predefined grooves to receive the snap ring). The test tool may be configured to displace the tell-tale to a position indicative of the maximum test dog extension, with the tell-tale remaining in that position during retrieval. The test tool may be reset for use in subsequent runs, such as by resetting the tell-tale snap ring into the first groove corresponding to the run-in configuration.

The test tool may comprise a drift diameter, the drift diameter of the test tool corresponding to the inside diameter (ID) that the pipe manufacturer guarantees per specifications. The nominal inside diameter of the wellbore may not be the same as the drift diameter but slightly larger. The drift diameter may be used by an operator or well planner to determine what size tools or strings can be run through the wellbore (in contrast to the nominal inside diameter -which may be used for fluid volume, flow calculations, etc.).

The method may comprise checking a profile, such as a landing profile. The landing profile may comprise a nipple. The method may comprise using the test tool with a position or depth measurement to measure the position or depth at which passage of the test tool string is halted. The method may comprise checking a position. The method may comprise registering the position. The method may comprise measuring the position. The position may comprise the depth of the test tool, noting that the depth may not necessarily be a vertical depth, but reflective of a length of passage of the test tool in the wellbore -which may be branched, deviated or comprise at least horizontal portions. The position may comprise the position of the profile and/or dog pocket. For example, the method may comprise measuring a position, such as a depth, of the test tool when it engages the landing profile. The method may comprise checking this measured or registered position of the test tool with a known or expected location of the landing profile, such as corresponding to a known or planned deployment location of the landing profile during a completion. The relative position of the dog pocket to the landing profile may be known. For example, the position of the dog pocket relative to the landing profile may be predefined and fixed. The locking recess profile may be comprised in the general profile of the landing profile. The landing profile may vary according to respective manufacturer's specifications and/or particular wellbore (e.g. variations in diameters, bore lengths, etc.).

The test tool may be comprised in a test string as a bottommost tool. Accordingly, the test tool may be the lowermost tool in the test string and the first portion of the test string to engage or pass into the landing profile. Alternatively the test tool may comprise an intermediate tool in the test string, with a portion of the test string extending below the test tool. Accordingly, the test tool may comprise a connector or connection at its lower and/or upper ends, for connection to other portions of the test string. The test tool may comprise a throughbore/s to allow passage of fluid through the test tool (e.g. from below to above the test tool and/or vice versa, from above to below).

The method may comprise providing an operator with reassurance that: the desired downhole location is accessible with a tool with the drift diameter; that the landing nipple is suitably engageable; and that the locking recess is suitably accessible and useable. This reassurance may be provided in advance of running in a tool for locking in to the profile, such as prior to running in a lock mandrel.

The method may comprise running a tool for engaging the landing profile, subsequent to the running and testing of the landing profile and lock dog pocket/s with the test tool. For example, the method may comprise running a lock or lock mandrel. The method may comprise running the lock or lock mandrel separately from the test tool. The lock or lock mandrel may comprise a downhole device that is placed and anchored within the tubing string to provide a setting point for equipment such as flow-control valves, chokes and plugs. The lock or lock mandrel may comprise a nipple lock for locating and securing within the landing profile. The method may comprise running the lock or lock mandrel after testing with the test tool. The method may comprise running the lock or lock mandrel after testing with the test tool. The method may comprise deploying the lock or lock mandrel after the operator has received feedback from testing with the test tool.

The method may comprise running an assembly into the wellbore after the testing tool.

The method may comprise running an assembly into the wellbore after the testing tool has been retrieved to surface. The assembly may comprise the lock or the lock mandrel. The method may comprise running an assembly into the wellbore after testing with the test tool. The method may comprise deploying the assembly after retrieval of the test tool. The method may comprise deploying the assembly into the wellbore after retrieval of the test tool to surface. The method may comprise deploying the assembly after an operator has had an opportunity to check the test tool, such as to verify the indicator indicates a successful extension of the test dogs to at least the minimum sufficient diameter.

The assembly may comprise a flow control device, such as one or more of a plug, choke, valve or the like. The assembly may comprise a jar for activating lock dogs of the assembly, such as of the lock mandrel. The assembly may comprise a tool, such as an indexer, for varying a rotational orientation of the lock dogs. For example, where the operator has previously successfully tested the lock dog pocket with the test tool on a previous run, if the operator is unable to successfully lock the lock dogs of the lock mandrel, the operator may be reassured that it should be possible, based upon the previously-successful test run. Accordingly, the operator may seek to try to engage a different circumferential portion/s of the locking recess -in the eventuality that a circumferential portion of the annular locking recess was not tested for accessibility/viability by the test dogs.

The method may comprise performing operations with wireline, slickline, coiled tubing or the like.

According to an aspect there is provided an apparatus for testing a portion of a wellbore, such as with the method of any other aspect, example, claim or embodiment.

The apparatus may comprise a landing profile test apparatus.

According to an aspect, there is provided a kit or array of apparatuses or devices. The kit may comprise the apparatus of any other aspect. In at least some examples, the kit comprises a plurality of the test tools of any other aspect, claim, example or embodiment. The plurality of tools may comprise tools of a variety of configurations. For example, different tools of the plurality may be configured for testing different landing profiles. For example, tools may comprise different dimensions, such as of one or more of: diameters, no-gos, offsets. The plurality of tools may be configured or configurable to suit or match a plurality of landing profiles, such as provided by different landing profile manufacturers.

According to an aspect, there is provided a system comprising a controller or a system arranged to perform a method according to an aspect, claim, embodiment or example

of this disclosure.

According to an aspect, there is provided computer software which, when executed by a processing means, is arranged to perform a method according to any aspect, claim, embodiment or example of this disclosure. The computer software may be stored on a computer readable medium. The computer software may be tangibly stored on a computer readable medium. The computer readable medium may be non-transitory.

Any controller or controllers described herein may suitably comprise a control unit or computational device having one or more electronic processors. Thus, the system may comprise a single control unit or electronic controller or alternatively different functions of the controller may be embodied in, or hosted in, different control units or controllers.

As used herein the term "controller" or "control unit" will be understood to include both a single control unit or controller and a plurality of control units or controllers collectively operating to provide any stated control functionality. To configure a controller, a suitable set of instructions may be provided which, when executed, cause said control unit or computational device to implement the control techniques specified herein. The set of instructions may suitably be embedded in said one or more electronic processors. Alternatively, the set of instructions may be provided as software saved on one or more memory associated with said controller to be executed on said computational device. A first controller may be implemented in software run on one or more processors. One or more other controllers may be implemented in software run on one or more processors, optionally the same one or more processors as the first controller. Other suitable arrangements may also be used.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

The invention includes one or more corresponding aspects, embodiments or features in isolation or in various combinations whether or not specifically stated (including claimed) in that combination or in isolation. For example, it will readily be appreciated that features recited as optional with respect to the first aspect may be additionally applicable with respect to the other aspects without the need to explicitly and unnecessarily list those various combinations and permutations here (e.g. the apparatus or device of one aspect may comprise features of any other aspect).

Optional features as recited in respect of a method may be additionally applicable to an apparatus or device; and vice versa.

In addition, corresponding means for performing one or more of the discussed

functions are also within the present disclosure.

The above summary is intended to be merely exemplary and non-limiting.

Various respective aspects and features of the present disclosure are defined in the appended claims.

It may be an aim of certain embodiments of the present disclosure to solve, mitigate or obviate, at least partly, at least one of the problems and/or disadvantages associated with the prior art. Certain embodiments may aim to provide at least one of the advantages described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 shows an example of a profiled portion of a wellbore, with a landing nipple; Figure 2 shows an example of a solid drift tool for running-in to check a landing profile, such as the landing nipple of Figure 1, with the tool shown in a side view in Figure 2a, a section view in Figure 2b and a plan view in Figure 2c; Figure 3 shows an example of a test method according to an embodiment of the 25 invention; Figure 4 shows an example of a test tool according to an embodiment of the invention; Figure 5 shows the test tool of Figure 4 in an activated configuration; Figure 6 shows the test tool of Figure 4 in a run-out configuration; Figure 7 shows a schematic partial cutaway sideview of the test tool of Figure 4, with the tool shown in respective configurations in Figures 7a, 7b and 7c respectively; Figure 8 shows a 3/4 isometric view of the tool of Figure 4; and Figure 9 shows a further example of a test tool.

DETAILED DESCRIPTION

Figure 1 shows an example of a profiled portion of a wellbore 2, here with a landing profile with a no-go 4. It will also be appreciated that other profiles of landing nipple different from that shown here may be provided in other examples: such as where different manufacturers or suppliers may provide profiles of different dimensions (e.g. different inner/outer diameters, different lengths of seal portion, different sizes of dog pockets, different offsets between the no-go and the dog pocket, etc.). The tool/s to be used in association with the landing nipple may be configured according to the particular landing nipple being used or targeted. For example, the tool/s may comprise dimensions corresponding to or in dependence upon the dimensions of the particular landing nipple. For example, the offset between the lock dogs of the tool and a no-go shoulder of the tool may correspond to the offset between the no-go 4 of the landing profile and the lock dog pocket 6.

Figure 2 shows an example of a solid drift tool 10 for running-in to check a landing profile, such as the landing profile 2 of Figure 1. The drift test tool 10 of Figure 2 only may be generally similar to conventional solid drift tools used to check access to the landing profile 2. The tool 10 has a no-go shoulder 16 for engaging the no-go 4 in the landing profile. Once engaged, the operator has verification of access to a depth or position corresponding to the known position of the landing profile. However, noting that the upper shoulder 11 of the landing profile is also very close relatively (e.g. within 30 cm at a depth of several thousand kilometres), then it is possible that the tool 10 shown in Figure 2 merely tags the upper cavity 9 and not even the no-go 4.

Accordingly, the tool 10 shown in Figure 2 may provide a false positive indication of successful passage of the tool 20 into the bore/s 7, 8 of the landing profile 2.

Such problems with the tool of Figure 2 may be prevented or at least mitigated by the tool/s of the present disclosure, such as shown in Figures 4 through 9. As shown in Figure 3, there is provided a method of testing the portion 2 of a wellbore according to the present disclosure. The method comprises checking or testing a cavity, which here is the log dog pocket 6 shown in Figure 1, such as to verify suitability of the log dog pocket 6 for receiving a lock dog or keys. As shown in Figure 4, there is provided a test tool 20 for testing the portion 2 of the wellbore. The method comprises running the test tool 20 into the wellbore prior to running a subsequent operation tool (not shown) into the wellbore 2 in a subsequent run. The landing profile test tool 20 here comprises a drift test tool 20 for checking or testing an inner diameter of the downhole landing profile 2; and measuring and verifying the location of the landing profile 2 and access thereto.

The method comprises testing the lock dog pocket 6 with test dogs 22 of the test tool 20 in advance of running in a subsequent tool for locking in the lock dog pocket 6. The method comprises only briefly and temporarily extending the test dogs 22 into the lock dog pocket 6. The method comprises retracting the test dogs 22 after extension into the lock dog pocket 6, as shown in Figure 6 and Figure 7c with the test tool 20 in a run-out configuration. The method comprises only extending the test dogs 22 to test the lock dog pocket 6; and not to lock the tool 20. Accordingly, the method comprises extending the test dogs 22 without locking the test tool 20 in the landing profile. The method comprises extending the test dogs 22 into the lock dog pocket 6 without engaging a sealing bore 7/8 of the landing profile 2. The test tool 20 does not comprise any seals. The test tool 20 here is run in on slickline (not shown), together with a jarring tool (not shown). The method comprises extending the test dogs 22 with the jarring tool, with the jarring tool being activated once the test tool 20 has engaged the landing profile 2.

The method comprises running-in the downhole test tool 20 to perform a test of the landing nipple 2 in advance of running-in a subsequent tool for landing on the landing nipple, the test tool 20 comprising the test dogs 22 for performing the test of the lock dog pocket 6 associated with the landing nipple 2. As shown in Figure 3, the method can comprise retrieving the test tool 20 to verify success of the test of the lock dog pockets 6. Accordingly, the method comprises running-in the test tool 20 to test both the landing nipple 2 and the lock dog pocket 4. The same test tool 20 is utilised to perform both the landing nipple test and the lock dog pocket test.

Accordingly the methods disclosed herein comprise an improvement on landing nipple checks with a simple, solid drift or test tool 10 such as shown in Figure 2. Once the test tool 20 of Figure 4 has engaged or tagged the landing nipple 2 (e.g. as confirmed by passage of the string being halted at a depth corresponding to the known or expected depth or location of the landing nipple 2), rather than merely retrieve the drift or test tool 20, the test tool 20 is used to perform an additional check or test of the viability of the locking recess 6 associated with the landing nipple 2.

The method comprises activating the test tool 20 by extending the test dogs 6, as illustrated in the transitions from Figure 4 to Figure 5; and from Figure 7a to 7b. The method comprises extending the test dogs 22 using a relative axial movement between portions of the test tool 20, instigated by the jarring tool (not shown). The tool comprises an upper portion 24 and a lower portion 26, the upper portion 24 being movable relative to the lower portion 26 to cause extension and retraction of the test dogs 22. The method comprises activating the test dogs 22 by generating relative axial movement between the upper and lower portions 24, 26 of the test tool 20 to extend and retract the test dogs 22 using a cam member 28, the relative axial movement to retract the test dogs 22 being a reversal of the axial movement to extend the test dogs 22. Here, the test dogs 22 are retracted by pulling the test tool 20 to axially move the cam member 28 associated with the test dogs 22, as shown in the transitions from Figure 5 to Figure 6; and from Figure 7b to Figure 7c.

The method here comprises testing a portion or fraction of the lock dog pocket 6. In other methods, the testing comprises testing the full 3600 of the circumference of the dog pocket 6, such as by rotating the test tool 22 (e.g. with extended test dogs 22) with an indexer (not shown). The test dogs 22 shown in the test tool 20 may differ from lock dogs (not shown) intended to engage the lock dog pocket 6 to lock a subsequent tool (not shown) to the landing profile 2. The test dogs 22 here comprise a greater proportion of the circumference than dogs of a tool to be subsequently run. The test dogs 22 here comprise at least 50% of the circumference, with the test dogs 22 shown here comprising a total of 2000 or more of the 360° total circumference. The test dogs 22 are equally spaced around the circumference.

The method comprises providing a positive indication of extension of the test dogs 22 only after a successful extension of the test dogs 22. The successful extension of the test dogs 22 comprises the extension of the test dogs 22 to at least a minimum position or extension. For example, successful extension is only achieved when the test dogs 22 have been extended to a diameter corresponding to at least a minimum diameter, the minimum extension diameter being greater than an inner diameter in the wellbore at a location elsewhere, such as uphole, of the lock dog pocket 6. For example, as shown in Figures 1 and 7, the lock dog pocket 6 comprises a larger inner diameter than the inner diameter of tubulars and cavities uphole of the lock dog pocket 6, such as the upper cavity 9 shown in Figure 1. Accordingly, the method comprises preventing indication of (successful) extension of the test dogs 22 if the test dogs have been extended at or in a wrong portion of the wellbore. For example, if the test tool's no-go 31 engages the upper shoulder 11 of the upper cavity 9 of the wellbore, rather than the no-go shoulder 4, then the test dogs 22 cannot be sufficiently extended. The method comprises preventing indication of (successful) extension of the test dogs 22 if the test dogs 22 have not been extended sufficiently fully in the lock dog pocket 6. For example, where access to the lock dog pocket 6 is obstructed or impeded, such as by corrosion or debris in the pocket 6, then the test dogs 22 cannot be fully or sufficiently extendable into the lock dog pocket 6. The indicator 32 is configured to prevent indication of successful test dog extension when the test dogs 22 have not been fully or sufficiently extended.

Figure 7 shows a series of sequential views in Figure 7a, 7b and 7c respectively, representing steps of the method of testing the landing profile 2 with the test tool 20.

As shown in Figures 6 and 7c, the indicator 30 comprises a visual indicator, which can be retrospectively checked when the test tool 20 is pulled to surface. The indicator 30 comprises a tell-tale, providing retrospective indication that the test tool 20 has been in a configuration with the test dogs 22 sufficiently extended to verify viability of the lock dog pocket 6. The indicator 30 is activated by the relative axial movement of the portions of the test tool 20. The indicator 30 is configured to only be activated once there is sufficient relative axial movement between the portions 24, 26 of the test tool 20 to correspond to a sufficient or at least minimum extension of the test dogs 22. During run-in and prior to activation, the portions 24, 26 are held in fixed relative axial positions by a shear screw 34. The indicator here comprises a snap ring 30 configured to change axial position in dependence on relative axial movement between the portions 24, 26 of the test tool 20. The test tool 20 is configured to axially displace the snap ring 30 to indicate an amount of relative axial movement between the portions 24, 26 of the test tool 20. The test tool 20 comprises predefined locations for the snap ring 30, shown here as a pair of annular grooves 36, 38 for receiving the snap ring 30. The first groove 36 corresponds to the location of the snap ring 30 during run-in and prior to extension of the test dogs 22, as shown in Figures 4 and 7a. The second groove 38 corresponds to the location of the snap ring 30 after successful extension of the test dogs 22 to the minimum or sufficient extension diameter. The axial separation between the first and second grooves 36, 38 corresponds to the relative axial movement between the portions 24, 26 of the test tool 20 and is dependent on a cam geometry of the cam member 28 associated with extending and retracting, the test dogs 22. The test tool 20 is configured to displace the tell-tale snap ring 30 to a position indicative of the maximum test dog extension, with the tell-tale remaining in that position during retrieval. The test tool 20 can be reset for use in subsequent runs, such as by resetting the tell-tale snap ring 30 into the first groove 36 corresponding to the run-in configuration.

The test tool 20 comprises a drift diameter, the drift diameter of the test tool 20 corresponding to the inside diameter (ID) that the pipe manufacturer guarantees per specifications. The nominal inside diameter of the wellbore 2 is not the same as the drift diameter but slightly larger. The drift diameter is used by an operator or well planner to determine what size tools or strings can be run through the wellbore (in contrast to the nominal inside diameter -which is used for fluid volume, flow calculations, etc.).

The method comprises checking the landing profile 2 by using the test tool 20 with a position or depth measurement to measure the position or depth at which passage of the test tool 20 string is halted by the no-go 4 when the test tool 20 engages the landing profile 2. The method comprises checking this measured or registered position of the test tool 20 with a known or expected location of the landing profile 2, such as corresponding to a known or planned deployment location of the landing profile during a completion.

As shown in Figures 4 through 8, the test tool 20 here is comprised in a test string (not shown) as a bottommost tool. Accordingly, the test tool 20 is the lowermost tool in the test string and the first portion of the test string to engage or pass into the landing profile 2. Accordingly, the test tool 20 only has a connector 40 at its upper end, for connection at the bottom end of the test string. The test tool 20 comprises a throughbore 39 to allow passage of fluid through the test tool 20 (e.g. from below to above the test tool 20 and/or vice versa, from above to below).

As shown in Figure 9, an alternative or adapted version of a test tool 120 is an intermediate tool in the test string, with a portion of the test string (not shown) extending below the test tool 120. Accordingly, the test tool 120 in Figure 9 comprises a respective connector or connection 140, 142 at both its lower and upper ends, for connection to other portions of the test string. The test tool 120 shown in Figure 9 is generally similar to that shown in Figure 8, with similar features denoted by similar reference numerals incremented by 100. Accordingly, the test tool 120 comprises a throughbore 139.

The method comprises providing an operator with reassurance that: the desired downhole location is accessible with a tool with the drift diameter; that the landing nipple is suitably engageable; and that the locking recess is suitably accessible and useable. This reassurance is provided in advance of running in a tool for locking in to the profile, such as prior to running in a lock mandrel.

Although not illustrated, it will be appreciated that the method here further comprises running a tool for engaging the landing profile, subsequent to the running and testing of the landing profile and lock dog pocket/s with the test tool 20. For example, the method comprises running a lock or lock mandrel separately from the test tool 20, which is subsequently placed and anchored within the tubing string to provide a setting point for equipment such as flow-control valves, chokes and plugs. Accordingly, the method comprises running an assembly into the wellbore after the testing tool 20 has been retrieved to surface. The method comprises deploying the assembly after an operator has had an opportunity to check the test tool 20, such as to verify the indicator 30 indicates a successful extension of the test dogs 22 to at least the minimum sufficient diameter in the lock dog pocket 6. The assembly comprises a flow control device, such as one or more of a plug, choke, valve or the like. The assembly comprises a jar for activating lock dogs of the assembly, such as of the lock mandrel.

It will be appreciated that embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage such as, for example, a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape. It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs that, when executed, implement embodiments of the present invention. Accordingly, embodiments provide a program comprising code for implementing a system or method as disclosed in any aspect, example, claim or embodiment of this disclosure, and a machine-readable storage storing such a program. Still further, embodiments of the present disclosure may be conveyed electronically via any medium such as a communication signal carried over a wired or wireless connection and embodiments suitably encompass the same.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The applicant indicates that aspects of the present disclosure may consist of any such individual feature or combination of features.

It should be understood that the embodiments described herein are merely exemplary and that various modifications may be made thereto without departing from the scope of the disclosure. For example, it will be appreciated that although shown here with four or six test dogs, other arrangements of test dogs are also possible.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. The claims should not be construed to cover merely the foregoing embodiments, but also any embodiments which fall within the scope of the subsequently appended claims.

Claims

CLAIMS1. A method of testing a portion of a wellbore, the method comprising: running a test tool into the wellbore prior to an operation in the wellbore; and checking a lock dog cavity to verify suitability of the lock dog cavity for receiving a lock dog.
2. The method of claim 1 wherein the lock dog cavity is checked by temporarily extending a test dog into the cavity prior to a subsequent extension of a lock dog into the cavity.
3. The method of claim 1 or claim 2, wherein the test tool comprises a drift test tool; and the method comprises testing an inner diameter of the wellbore.
4. The method of any preceding claim, wherein the test tool comprises a landing profile test tool; and the method comprises testing a downhole landing profile, including at least one of: measuring and/or verifying a location of a landing profile and/or access thereto.
5. The method of any preceding claim, wherein the method comprises testing the lock dog cavity with the test tool in advance of running in a subsequent tool for locking in the lock dog cavity.
6. The method of any preceding claim, wherein the method comprises checking the lock dog cavity to verify suitability of the lock dog cavity for receiving a lock dog, wherein the checking comprises testing the lock dog cavity with a test dog.
7. The method of claim 6, wherein the method comprises temporarily extending the test dog into the lock dog cavity; and retracting the test dog after extension into the lock dog cavity.
8. The method of claim 6 or 7, wherein the method comprises only extending the test dog to test the lock dog cavity and not to lock the tool.
9. The method of any of claims 6 to 8, wherein the method comprises running the test tool in together with a jarring tool; and the method comprises extending the test dog with the jarring tool, with the jarring tool being activated once the test tool has engaged a landing nipple.
The method of any preceding claim, wherein the method comprises running the test tool in on slickline, e-line, wireline, coiled tubing, drill -pipe or the like.
11 The method of any preceding claim, wherein the method comprises retrieving the test tool to verify success of the test of the lock dog cavity.
12 The method of any preceding claim, wherein the method comprises performing an operation subsequent to the testing of the portion of the wellbore, the operation comprising the subsequent running-in of an operation tool and locking the operation tool in the tested log dog cavity.
13 The method of any preceding claim, wherein the method comprises testing only a portion of the lock dog cavity.
14 The method of claim 13, wherein the method comprises only testing a portion of the 3600 of the circumference of an annular locking cavity.
A downhole test tool for testing a portion of a wellbore prior to an operation in the wellbore; the test tool comprising a log dog cavity test tool for checking a lock dog cavity to verify suitability of the lock dog cavity for receiving a lock dog.
16 The test tool of claim 15, wherein the test tool comprises a test dog for temporarily extending into the cavity.
17 The test tool of claim 16, wherein the test dog differs from a lock dog intended to engage the lock dog cavity to lock a subsequent tool to the landing profile.
18 The test tool of any of claims 15 to 17, wherein the test tool is configured to test the log dog cavity without locking.
19 The test tool of any of claims 15 to 18, wherein the test tool does not require any seals.
The test tool of any of claims 15 to 19, wherein the test tool is configured to test both a landing nipple and the lock dog cavity.
21 The test tool of any of claims 15 to 20, wherein the test tool comprises an indicator for providing an indication of lock dog cavity testing.
22 The test tool of any of claims 15 to 21, wherein the test tool comprises a drift diameter, the drift diameter of the test tool corresponding to an inside diameter associated with the wellbore.
23 A test string comprising the tool of any of claims 15 to 22.
24 The test string of claim 23, wherein the test tool is comprised in the test string as a bottommost tool.The test string of claim 23, wherein the test tool is comprised in the test string as an intermediate tool in the test string, with a portion of the test string extending below the test tool.