MEASURING DRILLING PARAMETERS OF A DRILLING OPERATION

Abstract

Described is apparatus housing an instrumented device and an inner tube providing a fluid flow path therethrough. A strain gauge is on the outer surface of the inner tube. Bulkhead(s) transfers forces from an external housing to the inner tube to be detected by the strain gauge. Flow sensors measure fluid flow velocity and/or fluid flow volume rate. Pressure sensors sense pressure differential between an inlet side and an outlet side of the apparatus. Sensors provide for measurement of RPM, WOB, azimuth and rate of penetration. Communication means (such as a Wi Fi transceiver) and/or GPS device can communicate through EM transparent windows. The apparatus is used aboveground axially in-line in a drill string.

Claims

1. An apparatus configured to be connected axially in-line in a drill string for measuring at least one parameter of a drilling operation, the apparatus including a housing, a conduit providing a fluid flow path through the housing, the conduit being connected to the housing at at least two spaced locations, and a device including electronics and at least one sensor, the at least one sensor being provided within the housing, wherein the at least one said sensor is provided on any one or more of: an external wall of the conduit within the housing; an internal face of a side wall of the housing; and; an external face of a side wall of the housing, and wherein the at least one said sensor includes at least one strain gauge.

2. (canceled)

3. (canceled)

4. (canceled)

5. The apparatus of claim 1, wherein at least one said sensor and electronics within the housing communicate wirelessly through the respective wall.

6. (canceled)

7. The apparatus of claim 1, wherein the conduit, includes a thinner walled section than one or more thicker walled sections with respect thereto.

8. The apparatus of claim 1, including a power generator to generate power to power electronics of the apparatus and/or to charge at least one charge storage device.

9. (canceled)

10. The apparatus of claim 8, wherein the power generator harvests kinetic energy from fluid flow through the device.

11. The apparatus of claim 1, including fluid flow sensing means for sensing fluid flow through the apparatus, including at least one flow meter to measure the flow (volume, rate) passing through the inner tube.

12. The apparatus of claim 11, including fluid flow sensing by at least one flow sensor arrangement by detecting inlet and outlet pressure differential, by Bernoulli effect of fluid flow through the apparatus and/or by sensing rotation of a turbine or power generator in the fluid flow.

13. The apparatus of claim 1, further including at least one pressure sensor.

14. The apparatus of claim 13, wherein the at least one pressure sensor senses a pressure impulse.

15. The apparatus of claim 1, wherein the conduit is directly or indirectly connected to the housing towards or at each end of the housing/apparatus.

16. (canceled)

17. The apparatus of claim 1, further include at least one flat surface on external surface of the pipe to enable fitment of a tool, and at least one an internal flange and/or bulkhead proximal to the respective flat(s) providing structural reinforcement.

18. The apparatus of claim 1, including a communication means and/or may provide signals to a communication means.

19. The apparatus of claim 18, further including at least one communication means to communicate with a device downhole, wherein the communication means is mounted or embedded internally of the housing.

20. (canceled)

21. The apparatus of claim 19, wherein the at least one communication means transmits/receives data through an electromagnetically (EM) transparent window through the housing.

22. The apparatus of claim 1, including separate compartments for electronics and charge storage.

23. The apparatus of claim 22, wherein the compartments are divided by at least one internal bulkhead.

24. (canceled)

25. The apparatus of claim 1, including one or more visual indicators provided to be visible through or on an external side wall of the housing.

26. The apparatus of claim 1, including a device for determining azimuth of the apparatus.

27. The apparatus of claim 26, wherein the azimuth is determined by a north seeking gyroscope.

28. (canceled)

29. The apparatus of claim 1, wherein the apparatus is provided in a drill string adjacent or towards a chuck or top drive of a drill rig.

30. The apparatus of claim 1, including at least one light and/or audible indicator, wherein the at least one light and/or audible indicator is any one or more of: provided on the device; provided remotely; annular and provided around a periphery of the device.

31. (canceled)

32. (canceled)

33. The apparatus of claim 1, including at least one collar mounted externally of the housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0149] Further advantages of the present invention will emerge from the following description of one or more preferred embodiment(s) of the present invention, given with reference to the accompanying drawing figures, in which:

[0150] FIGS. 1A and 1B show diagrammatic/schematic layouts of components for a drill string incorporating an embodiment of the present invention.

[0151] FIG. 2 shows a perspective internal view of an apparatus according to an embodiment of the present invention.

[0152] FIG. 3 shows electronics arranged to be mounted internally of an external housing according to an embodiment of the present invention.

[0153] FIG. 4 shows an exploded view of an apparatus according to an embodiment of the present invention.

[0154] FIGS. 5A and 5B show electrical charge storage means according to an embodiment of the present invention.

[0155] FIG. 6 shows detail of a portion of the apparatus with locating plate within the housing according to an embodiment of the present invention.

[0156] FIG. 7 shows internal arrangement of components of an embodiment of the present invention.

[0157] FIG. 8 shows internal arrangement of components of an alternative embodiment of the present invention with power generation from harvesting energy from fluid flow and/or sensing fluid flow.

[0158] FIG. 9 shows an instrumented internal conduit with strain gauges on an external wall of the internal conduit for the apparatus according to an embodiment of the present invention.

[0159] FIGS. 10A and 10B show features of external collars according to a further embodiment of the present invention.

DESCRIPTION OF PREFERRED EMBODIMENT

[0160] In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. The illustrative embodiments described in the detailed description, depicted in the drawings and defined in the claims, are not intended to be limiting. Other embodiments may be utilised and other changes may be made without departing from the spirit or scope of the subject matter presented.

[0161] It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings can be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.

[0162] As shown with reference to the Figures, an apparatus 10 embodying the present invention provides a housing 12 within which resides an instrumented device 13 and an inner tube 14 providing a flow path through the apparatus.

[0163] The apparatus can be connected axially in-line with a rod 66 of a drill string, such as a Kelly rod. A chuck 68 of a drill rig head 70 retains the rod during drilling operations. It will be appreciated therefore that the apparatus of the present invention being axially in-line with the drill rods can provide an accurate measure of direction to drill, such as azimuth, dip/inclination. Such measurement can be particularly useful at commencement of drilling to direct the drill hole in a required direction from a required location.

[0164] A saver sub 74 can be provided, such as in-line between the apparatus 10 and drill rods 72. A saver sub is a short piece of connecting pipe with threads on both ends, which is part of a drill string.

[0165] A swivel 76 can be provided to rotatably support/connect the drill string to a drive of the drill rig. The swivel can include a water connection for supply of water to the drill string.

[0166] The inner tube provides the flow path for fluid (such as air, water, drilling mud, or combinations of two or more thereof) to flow through the apparatus during a drilling operation.

[0167] It will be appreciated that the term ‘inner tube” is not intended to limit embodiments of the present invention to a simple straight walled circular section tube; rather, the term inner tube defines a flow path for fluid to flow through the apparatus.

[0168] In one or more embodiments, the inner tube can be a tube with relatively smooth bore internal wall of circular cross section. A straight bore inner tube is preferred in some instances, such as when the fluid is viscous or difficult to pump, or contains contaminants that might otherwise clog a more convoluted or separated flow pathway through the apparatus.

[0169] The instrumented device 13 includes electronics 16, such as for signal/data processing, storage and management, a Wi-Fi transceiver 18, a GPS module 20 and a charge storage device 22 (such as one or more batteries and/or capacitors) for powering the electronics.

[0170] The charge storage device 22 can include a a ring/annulus of battery cells 22a . . . n, the charge storage device 22 receives through the centre thereof the inner tube 14b.

[0171] Preferably the electronics 16 may be provided as an electronics module and the charge storage provided as a power module, the electronics module and the power module being receivable into the housing 12 from respective opposed ends of the housing.

[0172] The electronics module and/or the power module may each be provided around a respective portion of the inner tube. Separate portions 14a, 14b of the inner tube may have threaded sealing engagement with each other such that when each module is inserted into the housing, relative rotation of the inner tube portions connects the portions and seals the flow path.

[0173] One or other of the inner tube portions may include engagement portions for engaging with locating portions attached to the housing, such as on a locating plate 44. Thus, one of the modules may be fixedly located with respect to the housing while the other module can be rotated relative to the housing to connect and seal together the inner tube portions within the housing.

[0174] The housing may include one or more external flats 34 for engagement with a spanner or wrench to help rotate or prevent rotation of the housing when tightening the apparatus to a drill string or breaking the apparatus from a drill string, or when assembling and/or disassembling the internal electronics and/or power modules to/from the housing.

[0175] At least one strain gauge 48, preferably multiple strain gauges, is provided on the outer surface of the inner tube and connected to the electronics module. Torque and axial force are measured via strain gauged inner tube.

[0176] Force/load measurement can be provided through the inner tube and at least one associated bulkhead 54, preferably multiple bulkheads.

[0177] It will be appreciated that the bulkhead(s) transfers forces/loads from the external housing to the inner tube to be detected by the strain gauge(s). This provides for measurement of force and torque in parallel with the main outer stressed housing.

[0178] The transducer (strain gauge(s) and associated electronics) can be calibrated with lower forces than required otherwise. Also, because the strain gauge(s) is mounted to the outer surface of the inner tube, calibration, testing and maintenance can be done directly to the electronics module with the strain gauge(s) bonded to the inner tube before assembly into the housing.

[0179] It will be appreciated that the strain gauged inner tube transmits only a small portion of the load, the bulk of the load being taken by the non-instrumented outer member/tube, only a fraction of the force is required for calibration. As an example if apparatus senses only 5% of the total load, if a maximum load of, for example, 20 tonnes were present the strain gauged inner tube would only see a load of 1 tonne (5%). Hence, the inner tube can be calibrate with a maximum load of 1 tonne, thereby requiring much smaller equipment that is inherently safer for the operator due to the lower load.

[0180] Flow sensing of fluid flowing through the inner tube can be provided by one or more flow sensors 50. Flow sensing may measure fluid flow velocity (m/s) and/or fluid flow volume rate (m.sup.3/s).

[0181] Fluid flow differential (measured at two or more different points) may be provided. For example, measuring fluid flow at an inlet to the flow path and at an outlet to the flow path through the apparatus.

[0182] Fluid flow may be measured by at least one impellor rotating (speed and/or rate), magnetic device (e.g. cutting lines of flux or detecting ions/movement of ions in fluid flow) and/or Doppler device.

[0183] Pressure may be sensed by at least one pressure sensor 52.

[0184] Two or more pressure sensors may be employed to sense pressure differential between an inlet side and an outlet side of the apparatus. Pressure differential (Δp) between the inlet and outlet, or any two longitudinally separated points within the borehole, may be employed to determine depth within the borehole or drilling progress or efficiency (e.g. rate of fluid flow).

[0185] Preferably, at least one on-board pressure sensor 52 may be employed to sense or measure hoop stress compensation for strain measurement.

[0186] The apparatus 10 may include one or more accelerometers 56, such as to detect vibration, angular movement and/or position, or longitudinal and/or position movement (with respect to the borehole). Preferably a triaxial (x, y, z coordinate) accelerometers is provided.

[0187] Vibration may be detected by accelerometers provided in the apparatus. Also, energy harvesting through capture of kinetic energy from vibration, (e.g. by electromagnetic induction or piezoelectric device), may be used to power the device and/or recharge the energy storage.

[0188] Revolutions per minute (RPM) of the apparatus (and therefore the drill string) may be sensed. For example, the accelerometers may be employed to sense RPM via centripetal acceleration.

[0189] Gravity vector component (e.g. frequency) may be detected by a rotational vector sensor. The gravity vector component may be detected with the accelerometers and its frequency used to determine rotational speed for all instances, with the exception of for vertical holes. For vertical holes measurement of centripetal acceleration is utilised. Accelerometers may be utilised to detect roll angle.

[0190] The apparatus can preferably internally self-calibrate centripetal acceleration/RPM against gravity vector frequency at any time except when drilling vertical holes. This ability provides a high confidence level in the centripetal acceleration determined RPM which otherwise may not have been the case.

[0191] Rate of penetration (ROP) may be derived from signals from the accelerometers, gyroscope(s) and/or change in depth and/or pressure measurement (such as progress from a reference at the top of the hole or change of pressure downhole). Weight on bit (WOB) may be sensed by the strain gauge(s).

[0192] The apparatus 10 may include a device 33 to measure azimuth, such as a north seeking gyroscope.

[0193] When the axis of a gyroscope is parallel to the Earth's spin axis, the gyroscope will be stable. However, if the axis of the gyroscope is not so aligned, the gyroscope will precess. Precession is a change in the orientation of the rotational axis of a rotating body, such as a gyroscope. Therefore, the gyroscope can be used to determine a direction (angle) to North to high precision.

[0194] It will be appreciated that the charge storage device (such as batteries/capacitors) can be replaced or checked whenever assembling or disassembling the apparatus into/from a drill string e.g. at drill string rod change) or before/after supply to drill site.

[0195] The extension 28, 29 to the housing end provides for a ‘saver’ portion by which the internal electronics and power modules are protected from damaged if the end of the housing becomes damaged. Only the outer housing 12 needs replacement.

[0196] The communication means 18 (such as a Wi Fi transceiver) and/or GPS device 20 can respectively be mounted to an internal facing recess or cavity of the housing 12. Antenna for each may communicate through an EM transparent window 30, 32. The EM transparent window may be of fibre-glass or polycarbonate or other non-metallic material of suitable strength and wear characteristics.

[0197] The material of the EM transparent window may include or be non-metallic, and may be a high strength polymer such as polycarbonate, or a tough material such as acetal, or an epoxy, or possibly a composite fibre material such as GRP or other, or a combination of two or more thereof.

[0198] Connection can be made by cable from the respective communications means and/or GPS to the electronics module and/or the power module. Having the communications means and/or the GPS module mounted to the internal recess/cavity in the inside wall of the housing avoids the need for relatively large and inflexible coaxial cables from respective board mounted communications/GPS modules to an antenna. Embedded (nub) antennae provide for space and performance (packaging) optimisation. Preferably, the antenna/antennae are smaller than a spanner flat of the apparatus, and therefore the respective antenna can be embedded/bonded beneath the spanner flat. The spanner is larger than the antenna but smaller than the spanner flat so spanner cannot transfer any reaction to the antenna. Also it cannot ‘stab’ the antenna because it is too wide. An alternative is a small wire ‘nub’ aerial that comprises a short single wire, whereby, packaging wise these are more convenient, however there are performance compromises with this type of aerial/antenna.

[0199] The inner tube can include a shaft 15 that varies in width/diameter along a length thereof. For example, the shaft 15 may be narrower in outside width/diameter (OD) where the at least one strain gauge is mounted to the shaft, and be wider/of greater outside diameter (OD) away from the at least one strain gauge. Such narrowing in width/diameter at the strain gauge(s) can be selected to vary, as required, the stiffness of the shaft of the inner tube to amplify strain and resolution from forces/load from the outer housing. It will be appreciated that the inner tube shaft 15 can be a shaft portion of a tube section of the inner tube.

[0200] Preferably, one or both ends of the device (electronics and power modules) within the housing can be connected together and connected to at least one n load transfer portion within the housing, such as a bulkhead, shoulder, plate, locking means etc. That is, a firm connection is provided between the device within the housing and the housing, to transfer forces/loads to the at least one strain gauge on the inner tube in parallel from outer housing.

[0201] Preferably the apparatus includes at least one flexible connection between sections of electronics to mitigate torque wind-up fatigue of electronics connections. For example, sections of electronics (e.g. power management, digital processing, data storage, digital to analogue conversion etc.) can be mounted on separate supports 17 spaced from each other. Supports can be plate like, preferably disc like, spaced along the inner tube within the housing. Flexible electrical/optical connections can be coupled between the electronics on said plates/discs to avoid transferring vibrations between electronics sections and maintain reliability and accuracy in the field.

[0202] Preferably, one or more aligners/locators 19 can be provided to ensure correct alignment of one support 17 relative to the next. This can assist in ensuring that connectors 21 between supports 17 align and connect correctly. The aligners/locators 19 can be positioned such that the supports only align one way to ensure correct positioning and avoids assembly error(s).

[0203] Pressure sensor decoupling may be provided to prevent crevice corrosion e.g. damage by corrosive drilling mud. For example, a pressure sensor may be mounted in one of the bulkheads located at either end of the apparatus, e.g. the bulkhead forming one end of either the electronics enclosure or the battery enclosure. One side of the respective bulkhead is therefore exposed to the pressurised drill mud (up to 2000 psi typically), whilst the opposing side provides access to the electronics compartment at ambient pressure (˜1 bar abs.) The sensitive pressure sensor face can be protected from the corrosive drill mud (0<pH<10) by an intermediate chamber containing a fluid to transmit hydrostatic pressure to the sensor. The fluid may be an oil or similar non-electrolytic fluid. The intermediate chamber may be separated from the drill mud by a movable barrier such as a diaphragm or slidable piston e.g. to enable near lossless hydrostatic pressure transmission to the fluid.

[0204] A thread 82 at one or each of the ends of the apparatus for connecting the apparatus into a drill string may have a thicker thread wall than standard drill pipe in order to eliminate fatigue. Wireline type drill rods can range from 55 mm outside diameter (OD) to 114 mm OD and have a wall thickness between 5 and 6 mm. The height of a typical rod thread is of the order of 1/16″ (1.6 mm), and since the rod thread mean diameter is close to the middle of the wall by definition the wall thickness remaining at the thread root (the minimum wall thickness remaining that is) is approx. (½×5)−(½×1.6)˜1.8 mm thick. The minimum wall thickness that will be used on the apparatus in order to provide long life (i.e. minimal fatigue risk) may be more than double this, so >3.2 mm typically.

[0205] For example, the apparatus may have a coarser thread 82 for connection to a drill pipe than the drill pipe has, thereby reducing the risk of accidental break-out of apparatus from the drill string.

[0206] Use of stacked annular printed circuit assemblies (PCAs) and shields to optimize packaging, mitigate electromagnetic interference (EMI).

[0207] The electronic components are preferably soldered to the PCAs. In embodiments, the PCAs are circular to fit the inside diameter of the housing. They are screened from each other to prevent EM cross talk from one circuit to another.

[0208] A floating connector plate can be provided for mating connectors for the PCAs for torque displacement compensation.

[0209] Use of plug together modules for assembly purposes, otherwise it is inaccessible

[0210] One or more reinforcements, such as one or more bulkheads, can be provided within the housing, such as under the flat areas for engagement with a spanner/wrench. Such reinforcement(s) help to strengthen the housing where the side wall thickness of the housing at the flats may otherwise be reduced due to the inset nature of the flats relative to the curved outer surface of the housing.

[0211] Separation/isolation of electronics of the electronics module from the charge storage can be provided. For example, a barrier sealing a charge storage device space from an electronics module space may be provided. Such a barrier may include a wall, which may extend across the internal side wall of the housing to at least partially compartmentalise the electronics from the charge storage. Such a barrier may include an aperture for the inner tube to pass therethrough. One or more seals can be provided between the inner tube and the barrier and/or between the barrier and the housing side wall. Separating/isolating the electronics from the charge storage device helps to avoid contamination of the electronics during charge storage device replacement, such as battery replacement or charging.

[0212] One or more embodiments of the present invention can include at least one of a vibration detector and/or a sound detector. Sound detection may be provided by at least one microphone 60. The microphone may be mounted internally of the apparatus, with sound being transmitted though the sub housing wall. Airborne noise will be transmitted through the metalwork to the microphone.

[0213] Sound detection can be used to detect arrival of a downhole instrument or tool, such as an apparatus of the present invention, at a desired downhole location. For example, landing of a coring inner tube (with the apparatus of the present invention directly or indirectly connected thereto) downhole. Sound detection may be used to monitor/detect drilling progress/correct drilling.

[0214] Audio and/or visual indication may be provided to a computer, to a user/operator terminal and/or to one or more personnel at the surface, such as a drill operator. Such indication may be provided to inform (e.g. inform personnel) that an action is complete or a threshold has been met i.e. an over torque warning, wind up of the drill string, rate of penetration (ROP) falling below or above a respective threshold, fluid pressure increase or decrease, or other downhole event that has been identified.

[0215] Such indication can be provided by or augmented by one or more visual indications, such as by one or more lights. The lights (e.g. LEDs) may be embedded below the outer surface of the apparatus, and may be protected by a transparent/translucent barrier. The one or more lights may be provided external to, preferably mounted to, the housing e.g. mounted on a side wall.

[0216] A visual and/or audible indication may be provided from a lighting 88 and/or sound 90 arrangement. For example, the device may include one or more annular lights or a number of spaced lights around an exterior thereof 88. Because the apparatus rotates with the drill string, light indication that are visible as the apparatus rotates can be beneficial to operators.

[0217] Alternatively or in addition, the device may communicate to at least one remote lighting/audible arrangement 92. For example, a stacked light system to which the apparatus communicates will pick up the signal transmitted from the apparatus and display a required indication—such as RED—something not right, Amber—alert, Green—all is well. Audible alerts can be transmitted to match the light indications i.e. different pitches of sound and/or rate of intermittent sound.

[0218] At least one camera 86 can be provided for a visual recording. The camera(s) can be provided on the device 10, e.g. in the housing. The camera(s) can be synchronised to capture images/video so that the images are still or movie images during the rotation of the device e.g. a steady picture and the device can view the work area for monitoring and safety.

[0219] One or more embodiments of the present invention includes apparatus/methodology for user/personnel to take action if a set of conditions are met. For example, if a drill bit needs sharpening or vibration is too much to raise the RPM. The drilling operator/personnel can be provided with a display/view of settings and current drilling parameters/values (RPM, WOB, torque, ROP etc.), threshold settings, chart of sensor output vs time and configuration control, event logger etc. This may show drilling events against time and/or depth.

[0220] Data storage can be provided to store raw drilling data, a log of real time drilling events. A report generator can provide a report of drilling events and progress.

[0221] Voice/audible prompts may be provided to users/personnel, such as over threshold detection to earphone audio, and visual indications may be provided e.g. via lights indicators.

[0222] One or more algorithms may determine that action needs to be taken or a warning needs to be given, such as to increase or decrease RPM, WOB, fluid flow for flushing/cooling or to reduce vibration.

[0223] A carrier 43 for connectors can be provided that provides mechanical strength to the annular charge storage device/battery pack 22.

[0224] Stirrups 43a provide axial anchorage for an extraction handle/loop 45

[0225] A coarser thread 82 (rather than finer thread) to connect the apparatus to tube components of the drill string (such as drill rods, saver tube, Kelly rod) is preferred. An internal thread (not shown) can be provided at the opposite end.

[0226] Such thread can be provided in conjunction with lock collars 76, 78 (76a, 76b, 78a, 78b) to ensure easy break-out when disconnecting the apparatus from the drillstring. Lock collar halves 76a, 76b and 78a, 78b can be retained together by fasteners 80. The fasteners 80 can be released for separation of the halves for removal of the collars.

[0227] It can be necessary for the sub to remain attached in the drill string and adjacent to the drill head so that the drilling forces of the head are transmitted through it to the rest of the drill string. It is further preferred that whenever the driller adds or removes drill rods to the drill string, the rod threaded joints ‘break’ at a lower torque than the joint/s attaching the sub to the drill head, as the sub must remain firmly attached as an integral part of the drill head. To achieve this, a finer pitch can be used on the necessary joints on the sub so that for a given torque these would lock more tightly than the standard rod threads used. This works very effectively, however, it can be difficult to remove the sub itself from the head and the rig when necessary. Often the forces required to unthread the sub are so high that damage occurs to it, and in extreme case it may need to be cut off. This is clearly undesirable and threatens the viability of the device.

[0228] An alternative uses a thread with a similar thread and pitch as the drill string so that it can be more easily removed, and coupled with this incorporate a separate locking feature (rather than just the thread itself) to ensure it remains firmly coupled during normal operation.

[0229] One means of achieving this is to provide a flange proximal to each mating thread shoulder, to which a split collar 76a, 76b, 78a, 78b may in turn be fitted. The split collar thus locks the two adjacent flanges 84 together independent of the threaded joint, preventing the thread from unscrewing when torque is applied. The split collar would in turn be held in place by suitable means such as screws or clips or pins or suchlike.

[0230] Preferably the contact faces between the collar 76, 78 and flanges 84 are nearly orthogonal to the drill string axis so that the radial force component produced by the axial force arising from attempted unscrewing of the thread was minimal.

[0231] A charge storage device/battery pack 22 may be annular within the housing and around the central inner tube 14. For robustness, the cells, connectors and circuitry can be encased within an elastomer as this provided advantages such as mechanical compliance and shock resistance, sealing from the environment, and electrical isolation.

[0232] For increased strength, an annular metal carrier 44 can be incorporated at one end, which can also mount the connectors 40, 42 so that they do not rely on bond adhesion with the elastomer to remain in place and resist disconnection forces. This carrier can also be used to mount the protection and condition monitoring circuitry for the battery pack.

[0233] The battery pack can include a feature to enable the pack to be extracted from a blind cavity of the apparatus. A handle can be provided at the end distal from the connectors.

[0234] A mechanical link between the handle with distal end of the battery pack can ensure integrity. To achieve this, diametrically opposed stirrups can be provided fitted to several of the battery cells, with the base of the cell engaging the lower end of the stirrup, and the handle engaging the upper end.

[0235] The arrangement of the EM/RF transparent window and the communication means/module enabled the communication board/module to be rotated and thereby the antenna/aerial could be located both near the centre of the cylindrical cavity and close to the outer surface of the housing. This maximises the distance between the metalwork and the receive/transmit aerial and thereby optimises signal transmission/reception performance.

[0236] This configuration also enabled use of the chip antenna/aerial and avoid the need for larger patch aerials that are bulky within the space available. It also enabled the use of a commercial certified antenna/aerial and eliminated the need to go through the approvals process required of a non-standard aerial thereby saving both time and expense.

[0237] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

[0238] It is to be understood that, if any prior art is referred to herein, such reference does not constitute an admission that the prior art forms a part of the common general knowledge in the art, in Australia or any other country.

TABLE-US-00001 REFERENCE NUMBER TABLE No. Feature 10 Apparatus 12 Housing 13 instrumented device 14 Inner tube (14a, 14b) 15 Inner tube shaft 15a Inner tube shaft narrow portion 15b Inner tube shaft wider portion 16 Electronics module(s) 17 Support plates/discs 18 Wifi transceiver 19 Guides/locators 20 GPS 21 Connectors 22 Charge storage (batteries, capacitors) 23 Internal bulkhead 24 End cap 26 End cap 27a Conduit from end cap to inner tube 27b Conduit from end cap to inner tube 27c Tapered surface to conduit exit/entry 28 Extension, saver sub 29 Extension, saver sub 30 GPS window 32 Wi-Fi window 33 Azimuth device 34 Flats 36a Inner tube thread 36b Inner tube thread 38 Bulkhead plate 40 Power connection 42 Power connection 43 Carrier 44 Locating plate 45 Handle 46 Engagement means 48 Strain gauge(s) 50 Flow sensor(s) 52 Pressure sensor(s) 52a Pressure sensor(s) housing/cover 54 Bulkhead(s) 56 Accelerometer(s) 58 Barrier 60 Microphone(s) 62 Rotary power generator (turbine) 64 Reduced diameter/width conduit 66 Rod of drill string/Kelly rod 68 Chuck 70 Drill head 72 Additional drill rods 74 Saver sub 76 1.sup.st Collar 76a, 76b 1.sup.st Collar halves 78 2.sup.nd Collar 78a, 78b 2.sup.nd Collar halves 80 Collar fasteners 82 Thread 84 Flange(s) 86 Camera(s) 88 Light(s) 90 Sound/speaker(s)