Patent Description:
Ultrasound spans the range of sound frequencies that are higher than the range that can be heard by humans, and generally have frequencies of greater than <NUM>. Typical ranges of operation extend from <NUM> up to several Gigahertz. Due to the much higher frequencies involved, ultrasonic devices are typically very different from those generally used for audible applications.

Analysis using ultrasound waves shows great promise in a range of applications, particularly in imaging such as medical imaging but also in fields such as non-destructive testing (NDT), particularly in industrial NDT, and measurement, such as in measurement of pipe wall thicknesses, corrosion and erosion monitoring and other challenges in asset integrity management. However, ultrasound has a wide range of uses and the applications of ultrasound are not limited to these examples.

The ultrasound transducer is operable to produce ultrasonic waves that are transmitted into an object and detect reflections of the ultrasonic waves that are reflected from the interfaces between the layers of the sample or defects and objects inside the sample). By using techniques such as time of flight and other analyses, it is possible to image the layers of the sample and thereby characterise the sample.

Conventional ultrasonic transducers are generally formed from bulk ceramic materials, which can be high cost, bulky and difficult to manufacture, particularly with the shapes and properties desired for many applications. Traditional ceramic materials used in ultrasound are generally not suitable for very high temperature operation, making them unsuitable for some applications. In particular, the combination of being able to operate at high temperature and with sufficient resolution is problematic for many traditional ultrasound transducers. The ability to record an ultrasound measurement at high temperature is further limited by the requirement for a couplant material between the sensor and the object. Furthermore, traditional ultrasound transducers are not easy to manufacture using automated techniques and often require a high degree of manual operation. Improved ultrasonic transducers and methods for manufacturing them are therefore desirable.

<CIT> describes an ultrasonic transducer assembly, including a conformable ultrasonic transducer having a piezoelectric layer and electrodes able to conform to curved surfaces, and a clamp for pressing the transducer into ultrasonic contact with a curved surface.

<CIT> describes a band part of a band-shaped member having flexibility, which is tightened with a clamp. A plurality of ultrasonic sensors are bonded to an inner circumferential surface of the band part via an elastic member.

Various aspects of the present invention are defined in the independent claims. Some preferred features are defined in the dependent claims.

According to a first aspect of the present disclosure an ultrasonic device is as defined in claim <NUM>.

The at least one transducer may be a piezoelectric transducer. The at least one transducer may be a thin film transducer.

The test object may be or comprise a pipeline, conduit or other cylindrical member.

The device may be a high temperature device, configured to operate at high temperatures. For example, the device may be configured to operate above <NUM>, e.g. above <NUM> such as above <NUM>. The device may be configured to operate at temperatures between <NUM> and <NUM>, e.g. between <NUM> and <NUM>. The device may be configured to operate at temperatures below <NUM>, e.g. below <NUM> such as below -<NUM>, e.g. down to -<NUM>.

The device may be configured to measure temperature, or a property representative thereof, e.g. configured to measure temperature of the device and/or a region directly adjacent the device. The device may be, comprise or be comprised in a combined ultrasonic and temperature measurement device. The device may comprise one or more temperature sensors, which may be in addition to the piezoelectric transducers or one or more of the piezoelectric transducers may have a dual temperature measurement and ultrasonic generation and/or reception capability such that they are operable as both a temperature sensor and an ultrasonic transducer. The transducers may have both piezoelectric and pyroelectric properties.

The clamp may comprise one or more bands. Although the clamp beneficially may comprise bands, it will be appreciated that other clamping mechanisms could be used, such as gripping members, e.g. adjustable or resiliently deformable gripping members or the like. The choice of clamp may depend on the application and the amount of securing force that is required.

At least part or all of the one or more bands may be conformable and/or flexible. The one or more bands may be formed of or comprise conformable material, e.g. the one or more bands may comprise a conformable and/or flexible band or band portion.

The conformable band or band portion may be a band or portion of the band that is configured to face or abut the test object, in use. The conformable material may be an elastomeric material, such as a high temperature engineering polymer, which may be stable at temperatures of <NUM>, <NUM>, <NUM> or higher. The conformable material may optionally be or comprise fluoroelastomer, perfluoroelastomer, silicone blends, graphite based blends and/or the like.

By providing the conformable band or band portion the device may operate without a couplant, which may be particularly suited for high temperature and/or long term applications.

The at least one transducer or transducer array may be at least partially or fully embedded or moulded into the conformable band or band portion. The at least one transducer or transducer array may be inserted, or selectively insertable or removable into the conformable band or band portion, e.g. the at least one transducer or transducer array may be provided as an insert into the conformable band or band portion.

At least one or each of the bands may be or comprise a metal band. At least one or each of the bands may be or comprise a rigid or semi-rigid band.

The conformable band or band portion may be affixed to the metal or rigid or semi-rigid band. The conformable band or band portion may at least partially or totally enclose the metal band. The conformable band or band portion may mount the piezoelectric transducer or transducer array to the metal band.

The at least one transducer may have wiring that may be moulded through the conformable material and/or channelled between the conformable material and the metal band. The at least one transducer or transducer array may comprise a connector, such as a surface mount connector e.g. a microcoax connector, for connecting the transducer to an input signal source for receiving the drive signal for driving the transducers and/or to an output system for providing the output signal from the transducers to the output system. This arrangement may allow the transducers or transducer array to be connected with a separate wire, which may allow extra modularity.

The at least one band may be configured with a securer for locking the band to, and/or selectively releasing the band from, the test object and/or for adjusting the tension in the band. The securer may be or comprise a ratchet mechanism, screw / bolt closure, worm gear arrangement or the like. The securer may be configured to adjust the circumference of the at least one band, e.g. to tighten and/or loosed the at least one band on the test object, in use. The securer may be or may be comprised in a selective closure mechanism, for allowing the band to be selectively placed on and/or removed from the test object.

The use of the metal band in addition to the conformable band may provide the required structural strength to secure fix the device to the test object.

The clamp may or may not comprise the conformable band or band portion or conformable material, e.g. the clamp may comprise just the metal band, just the conformable band formed of the conformable material or a band having both a metal band and the conformable band portion formed from the conformable material. However, in those embodiments that do comprise the conformable material, then the conformable material may extend between the at least one piezoelectric transducer and the at least one metal band. The conformable material may be electrically insulating, e.g. the conformable material may electrically insulate the at least one piezoelectric transducer from the metal band. The conformable material may provide some protection for the at least one transducer. The conformable material may beneficially distribute force on the at least one transducer. The conformable material may also provide a degree of compensation for movement or expansion and contraction of the test object, which may be particularly applicable when the test object is a pipe or conduit designed to carry fluids of varying temperatures.

The device may comprise an urging mechanism, which may be configured to move, and/or apply a force on, the at least one transducer or transducer array, e.g. to axially move or apply a force on the at least one transducer or transducer array. The urging mechanism may be configured such that the position, e.g. axial position, and/or the force applied by the urging mechanism on the at least one transducer or transducer array is selectively variable or adjustable, e.g. by operation of the urging mechanism. The urging mechanism may be manually adjusted or automatically adjusted.

This arrangement may allow the force or interface between the at least one transducer or transducer array to be adjusted, e.g. for optimal acoustic transfer. This may be particularly beneficial with conformable devices comprising flexible transducers or transducer arrays and conformable material or buffers, particularly devices that are configured to operate without couplant, as the urging mechanism may provide a beneficial interface between the at least one transducer or the transducer array and the test object that would otherwise have been provided by the couplant.

The urging mechanism may comprise a screw or other rotational assembly. The screw or other rotational assembly may be operable into a configuration in which it acts on the at least one transducer or transducer array, e.g. to urge the transducer or transducer array towards and/or into contact with the test object, in use.

The coupling may accommodate the rotational motion of the screw or other rotational mechanism without transferring rotational motion to the at least one transducer or transducer array. The coupling may be or comprise a socket joint. This may prevent damage to the transducer or transducer array from grinding against the test object whilst still allowing travel in the axial direction to allow the transducer or transducer array to compress against a surface of the test object. The urging mechanism, e.g. the screw and/or the coupling may be formed of or comprise a rigid material, such as a metal, e.g. stainless steel.

A conformable buffer may be provided between the coupling and/or urging mechanism and the at least one transducer or transducer array. The conformable buffer may accommodate the flexible transducer or transducer array conforming to the shape of the test object whilst still applying a force from the urging mechanism to the transducer or transducer array, e.g. to urge the transducer or transducer array towards or onto the test object. The conformable buffer may more evenly distribute the urging force and may help avoid damage to the transducer or transducer array. The conformable buffer may also help accommodate expansion and/or contraction and/or other movement of at least part of the test object, and may help maintain good acoustic coupling. The conformable buffer may be configured to withstand high temperatures, e.g. <NUM>, <NUM>, <NUM> or higher. The buffer may be non-polymeric. The buffer may comprise graphite, fibre reinforced materials, minerals such as soft minerals, e.g. vermiculite, steatite, phyllosilicates, pyrophyllite, mica and/or calcium silicate, and the like.

Although an example of an urging mechanism in the form of a screw mechanism is detailed above, the urging mechanism is not limited to this. For example, the at least one conformable band or band portion or conformable material or other resiliently deformable material may be provided and be configured to perform the actions of the urging mechanism, e.g. to urge the transducer or transducer array towards and/or into contact with the test object, in use. In this case transverse extension, lengthening, tensioning or application of a force on the conformable band or band portion or conformable member or other resiliently deformable material may cause it to apply an axial force on the transducer or transducer array, which may urge the transducer or transducer array towards and/or into contact with the test object, in use. The tensioning may be carried out using the securer. Other examples of urging mechanisms include, piston / syringe / friction fit arrangements, quick release / asymmetric bolt and lever type mechanisms, and/or the like.

The transducers may be configured to produce and emit ultrasonic waves, e.g. responsive to a drive signal, and/or receive and detect ultrasonic waves, e.g. to receive and detect reflections of the emitted ultrasonic waves. The device may be an ultrasonic device for imaging, measurement or testing, e.g. non-destructive testing. The device may be a medical ultrasound imager. The device may be a non-destructive testing device. The transducers may be configured to provide an output signal representative of the received ultrasonic waves or one or more properties thereof, e.g. of the amplitude, frequency, wavelength, and/or timing of the ultrasonic waves. The transducers may be configured to emit ultrasonic wave and/or to detect and/or measure received reflections of the ultrasonic waves.

Having temperature sensor capability integrated into the device, may allow greater accuracy for measurements that are affected by temperature effects, such as wall thickness that is calculated from the time of flight measurement. For example, the temperature measurements at the sensor face may be used to compensate for changes in speed of sound with temperature rather than by using a computer model of heat transfer through a delay line or couplant.

The device may comprise a transducer array and the at least one transducer may be comprised in the transducer array. The transducer array may be a flexible transducer array. The at least one transducer and/or the transducer array may comprise a layer of piezoelectric material provided on a substrate, e.g. directly on the surface of a substrate. Each transducer of the transducer array may comprise one or more discrete electrodes provided directly on the layer material. The at least one transducer and/or the transducer array may comprise a layer of dielectric material, such as photoresist e.g. SU-<NUM>, deposited on the piezoelectric layer and/or between the discrete electrodes. The substrate may be, comprise or be comprised in a counter electrode. The substrate may be an electrically conductive substrate. The at least one transducer and/or the transducer array may comprise one or more electrical contacts coupled to one or more of the electrodes, e.g. to respective electrodes, by electrically conductive traces. The one or more electrical contacts and/or the electrically conductive traces may be provided on the substrate, on the piezoelectric layer and/or on the dielectric material. Individual electrodes and/or transducers may be individually addressable using respective conductive traces. The device may comprise one of more features of the ultrasound transducers disclosed in <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and/or <CIT>, all in the name of the present applicants.

The substrate may be a flexible and/or conformable substrate, such as a foil, which may be a metal foil, e.g. an aluminium foil. The piezoelectric material may be or comprise a metal or transition metal compound, such as a metal oxide or nitride, which may be a primary piezoelectric material. The piezoelectric material may be or comprise a zinc or aluminium compound, such as aluminium nitride (AIN) or zinc oxide (ZnO). The piezoelectric material may optionally be doped, e.g. with a transition metal or transition metal compound, such as Vanadium or Scandium. The piezoelectric material may be a crystalline, e.g. polycrystalline or columnar piezoelectric material. The piezoelectric material may be non-polymeric or may not be comprised in a polymeric material. The piezoelectric material may be or comprise a continuous layer of material having piezoelectric properties, e.g. the piezoelectric material may not comprise discrete domains of piezoelectric material having piezoelectric properties within a matrix of non-piezoelectric material. The layer of piezoelectric material may have a thickness in the range of <NUM> to <NUM>. The layer of piezoelectric material may be thinner than the substrate.

The piezoelectric material may be doped with a dopant or further material, e.g. with a transition metal or a compound thereof, e.g. with vanadium. The dopant or further material may be present in the piezoelectric material at a level up to <NUM>% with respect to weight, e.g. from <NUM> to <NUM>% w/w. The primary piezoelectric material, e.g. the metal oxide or metal nitride, may be present in the layer of piezoelectric material in levels from <NUM>% w/w up to <NUM>% w/w. The dopant or other material may be integrated, co-deposited or reacted into the primary piezoelectric material, e.g. alloyed with or doped into the primary piezoelectric material, and may not be mixed with or coated onto or in discrete domains with the primary piezoelectric material.

The device body may be formed from metal, polymeric material, and/or the like. For example, the device body may be formed of stainless steel. The device body may be rigid. The device body may be hollow, e.g. to accommodate therein the at least one transducer or transducer array and/or the urging mechanism and/or any wiring, connectors and/or electronics for operating the at least one transducer or transducer array. The clamp, e.g. the one or more bands, may pass through the device body, e.g. so that the device body can be securely fixed to the test object using the clamp.

However, it will be appreciated that the device body need not be rigid. For example, at least part of the at least one transducer or transducer array (and optionally at least one of the other components identified above or below as being housed in the device body) may be embedded or otherwise provided in the conformable material, such that the conformable material effectively acts as the device body.

For example, multiple devices may be provided as a sheet, wherein the sheet may be formed predominantly of the deformable material. The at least one transducer or transducer array may be embedded in the sheet or may be insertable into the sheet. The sheet may be cut to length, e.g. with a variable number of transducers, to suit a given application. The sheet may be provided on and/or feedable from a reel or spool. The sheet may comprise or be configured to receive a plurality of the transducers with different intra-transducer spacings between transducers, which may further allow devices with various configurations to be obtained.

The device may comprise a power source, such as a battery, capacitor, inductive power coupling system or other electrochemical, electrostatic or electromagnetic power source. The device may be wired or wireless. The device may receive power and/or the drive signal and/or may output the output signal via wired or other physical connectors. Alternatively or additionally, the device may receive the drive signal and/or provide the output signal wirelessly. The device may comprise a wireless communications system for communicating wirelessly with remote and/or separate devices, e.g. to receive the drive signal and/or to send the output signal. The wireless communications system may be configured to communicate using BluetoothRTM, ZigBeeRTM, WiFiRTM, WiMAXRTM, NFC, a cellular telephone and/or data network or other suitable communications channel or mechanism. Optionally the power for the device may be provided wirelessly, e.g. via inductive coupling. The drive signal may be provided by control electronics, which may be onboard the device, e.g. housed in the device body, and may be provided using the power source. The device may comprise or be configured to access data storage and the device may be configured to record the output signal, e.g. over time, in the data storage. The data storage may be on-board, e.g. within the device body and may be powered by the power source. The data storage may be external and/or remote from the device, e.g. such that the data is output from the device to the data storage, e.g. via wired or wireless communications.

The above arrangements may provide various advantages. For example, the device may be easier and/or quicker to install. The device may be securely clamped to a test object, e.g. pipe. The device may achieve and maintain good acoustic coupling between the at least one transducer or transducer array and the test object and may do so without the use of a couplant, such as a gel. The device may be easier to conform around the shape of a test object. The device may have a very low profile, which may be beneficial in certain applications such as deployment in confined spaces, around corners, close to joints, in complex and close networks of pipes and particularly in oil and gas pipelines with minimal disruption to the design of the pipelines.

According to a second aspect of the present disclosure is a method of manufacturing, repairing or assembling the device of the first aspect as is defined in claim <NUM>. The transducer may be a piezoelectric transducer. The method may comprise mounting the device body on the clamp or the clamp may be integral with the device body.

The method may comprise providing and mounting one or more temperature sensors. The one or more temperature sensors may be in addition to the one or more transducers or one or more of the transducers may have a dual temperature measurement and ultrasonic generation and/or reception capability such that they are operable as both a temperature sensor and an ultrasonic transducer. The clamp may comprise one or more bands, which may comprise one or more metal bands and/or conformable bands and/or conformable band portions. The method may comprise providing a securer for locking the band to, and/or selectively releasing the band from, the test object. The method may comprise providing an urging mechanism, which may be configured to urge the transducer or transducer array towards and/or into contact with the test object, in use. The urging mechanism may comprise a screw mechanism. The method may comprise providing a coupling between the urging mechanism, e.g. the screw, and the at least one transducer or transducer array. The method may comprise providing a conformable buffer between the coupling or urging mechanism and the at least one transducer or transducer array.

The method may comprise providing and mounting a power source, such as a battery, capacitor, induction power coupling system or other electrochemical, electrostatic or electromagnetic power source, which may be provided in the device body. The method may comprise providing and mounting a wireless communications system for communicating wirelessly with remote and/or separate devices. The method may comprise providing and mounting control electronics, which may be housed in the device body. The method may comprise providing and mounting data storage.

According to a third aspect of the present disclosure is a method of using the device of the first aspect as is defined in claim <NUM>. The method may comprise or be comprised in a method of obtaining non-destructive testing (NDT) data. The method may comprise or be comprised in a method of obtaining imaging data such as ultrasound imaging data, e.g. medical imaging. The method may comprise or be comprised in a method of obtaining measurement data, such as measurement of wall thickness.

The method may comprise placing the conformable band or band portion at least part or all of the way around the test object. The method may comprise providing the metal band at least part or all of the way around a test object. The method may comprise securing the clamp with the securer. The method may comprise operating the urging mechanism to bring the at least one transducer or transducer array into contact with, and/or to urge the transducer or transducer array onto a surface of, the test object.

According to an example of the present disclosure is computer readable code configured such that, when processed by an automated manufacturing system controller, causes the automated manufacturing system to produce at least part of the device of the first aspect and/or to perform the method of the second aspect.

The automated manufacturing system may comprise a 3D printer, additive manufacturing equipment, a robotic assembly system, a pick and placer, a computer numerical control (CNC) machine, and/or the like.

The individual features and/or combinations of features defined above in accordance with any aspect of the present invention or below in relation to any specific embodiment of the invention may be utilised, either separately and individually, alone or in combination with any other defined feature, in any other aspect or embodiment of the invention.

Furthermore, the present invention is intended to cover apparatus configured to perform any feature described herein in relation to a method and/or a method of using or producing, using or manufacturing any apparatus feature described herein.

These and other examples of the present disclosure will now be described, by way of example only, with reference to the accompanying Figures, in which:.

<FIG> show an example of an ultrasonic device <NUM> for emitting ultrasonic waves and receiving and measuring the reflected ultrasonic waves in order to produce a signal representative of one or more parameters of the received ultrasonic waves. The specific examples shown in <FIG> illustrate the use of the ultrasonic device in order to beneficially perform non-destructive testing, NDT, (e.g. wall thickness measurements) of a test object, which in this particular example is a pipe, such as an oil or other fluid or gas pipeline. However, the ultrasonic device <NUM> is not limited to this application and it will be appreciated that it could be used in other applications such as imaging, e.g. medical imaging, amongst others.

The device <NUM> comprises a device body <NUM>, a clamp <NUM> and one or more ultrasonic transducers (in this example a plurality of the ultrasonic transducers are provided in an ultrasonic transducer array <NUM>, which can be seen particularly in <FIG>, <FIG>).

As shown in <FIG>, in an example, the ultrasonic transducer array <NUM> is a flexible ultrasonic transducer array comprising a flexible, electrically conductive substrate <NUM>, in this example in the form of a metal foil, with a piezoelectric layer <NUM> on a surface of the substrate <NUM>. In this example, the piezoelectric layer <NUM> is in the form of a layer of non-polymeric, inorganic piezoelectric material, such as zinc oxide (ZnO) or aluminium nitride (AIN), optionally doped with a transition metal or transition metal compound such as vanadium. The piezoelectric layer <NUM> can be deposited directly onto the substrate by methods such as sputter coating and the like. In this example, the substrate <NUM> acts as a counter electrode and is arranged towards the test object <NUM> in use.

An array of electrodes <NUM> is provided on a surface of the piezoelectric layer <NUM> that is on an opposite side of the piezoelectric layer <NUM> to the substrate <NUM>, such that the piezoelectric layer <NUM> is between the electrodes <NUM> and the substrate <NUM>. Each electrode <NUM> is electrically connected to a corresponding electrical contact <NUM> by a respective conductive track <NUM>. Each electrode and the associated portion of the piezoelectric layer <NUM> and substrate <NUM> can be considered to form a transducer of the transducer array <NUM>. Each electrode <NUM> is individually addressable to drive the electrode <NUM> and to read out signals collected by the electrode <NUM>. Electrically resistive dielectric material, such as photoresist e.g. SU-<NUM>, can optionally be provided between the piezoelectric layer <NUM> and both the conductive tracks <NUM> and contacts <NUM> and also between discrete electrodes <NUM>, contacts <NUM> and conductive tracks <NUM> to mitigate against cross-talk.

For example, a control device (not shown) can be connected to the electrical contacts <NUM> to provide alternating drive signals to the electrodes <NUM> via the respective conductive tracks <NUM> in order to create a potential difference across the corresponding portions of the piezoelectric layer <NUM> that correspond to the driven electrode <NUM>, so as to cause the corresponding portion of the piezoelectric layer <NUM> to oscillate with a frequency corresponding to that of the drive signal to thereby produce an ultrasonic wave having a corresponding frequency. Reflections of the emitted ultrasonic waves can also be received by the ultrasonic transducer array <NUM>, causing at least portions of the piezoelectric layer <NUM> to oscillate, which thereby generates an electrical signal having a frequency dependent on that of the received ultrasonic wave. This can be received by the control device via the electrodes <NUM>, conductive tracks <NUM> and contacts <NUM>.

Examples of flexible ultrasonic transducers and ultrasonic transducer arrays that could be used (or at least features thereof) in the present examples are described in <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and/or <CIT>, all in the name of the present applicant.

The device body <NUM> in this example comprises a hollow metal enclosure that houses the ultrasonic transducer array <NUM> and any associated wiring and electronics. The device body <NUM> comprises an electrical connector <NUM> for connecting the contacts <NUM> of the ultrasonic transducer array <NUM> to the control device. The electrical connector <NUM> could be a microcoax connector, for example, but is not limited to this. The device body <NUM> comprises a plurality of feet <NUM>, designed to engage with the test object <NUM> in order to securely mount the device <NUM> onto the test object <NUM>.

The device body <NUM> is mounted onto the clamp <NUM>, e.g. by passing part of the clamp <NUM> through channels in the device body, by physical connection, and/or the like. In this example, the clamp <NUM> comprises a plurality of bands <NUM>. In this case the bands <NUM> are metal bands for strength and security, but are not limited to this. The bands <NUM> are configured to extend around at least part of the test object, in use, and to be selectively opened and closed. For example, the bands <NUM> may be configured to pass through channels in the device body <NUM> and to be secured by a screw, ratchet or other one-way mechanism, a lock lever, interference or press fit, a clip and/or the like.

As can be seen particularly in <FIG>, the flexible ultrasonic transducer array <NUM> is provided in the device body <NUM> and arranged such that an active (e.g. emitting / receiving) surface <NUM> or a coating such as a dielectric coating or membrane provided thereon is provided at an inner surface of the ultrasonic device <NUM> that is configured to abut and interface with the test object <NUM> in use. In the above example, the active surface is a surface of the substrate <NUM> that is opposite the surface of the substrate upon which the layer of piezoelectric material <NUM> is provided. The device comprises an urging mechanism <NUM> for urging the active surface of the ultrasonic transducer array <NUM> onto the outer surface of the test object <NUM>.

In the example of <FIG>, the urging mechanism <NUM> comprises a screw <NUM> threaded into a complementary threaded channel in the top of the device body <NUM> so as to be screwable into the device body towards the test object <NUM> and out from the device body <NUM> away from the test object <NUM>, in use. A proximal end <NUM> of the screw <NUM> is provided with a turning aid, such as a finger grip, and/or a slot, hex recess or other tool interface to allow the screw <NUM> to be easily turned.

A distal end <NUM> of the screw <NUM> engages with a coupling <NUM> that is provided between the screw <NUM> and the transducer array <NUM>. The coupling <NUM> accommodates the rotational motion of the screw <NUM> without passing on rotational motion to the transducer array <NUM>. Examples of suitable couplings <NUM> include a socket joint, bearing mechanism or the like.

The coupling <NUM> is also provided with a conformable buffer <NUM> that sits between the rest of the coupling <NUM> and the ultrasonic transducer <NUM>. The buffer <NUM> is resiliently deformable. The conformable buffer <NUM> can assist the flexible ultrasonic transducer array <NUM> in conforming to a curved surface of the test object whilst evenly distributing force over the transducer array <NUM>, thereby mitigating against damage to the transducer array <NUM>. The conformable buffer <NUM> also provides a degree of compensation for expansion/contraction of the test object with heating. However, the conformable buffer <NUM> is preferably configured to withstand the elevated temperatures, which may limit material selection, ruling out conventional engineering polymers and elastomers. As such, high temperature materials such as graphite, fibre reinforced materials or certain minerals such as vermiculite may be used for the buffer <NUM> to provide the desired temperature and accommodating properties.

In this way, in use, the screw <NUM> of the urging mechanism <NUM> may be operated in order to apply and vary an axial force of the transducer array <NUM> acting to urge the active surface <NUM> of the transducer array <NUM> onto the corresponding surface of the test object <NUM>. The urging mechanism <NUM> is therefore operable to achieve the desired acoustic coupling between the transducer array <NUM> and the test object <NUM>, preferably without the use of a couplant such as gel that may be disadvantageous or unsuitable for high temperature or long term use.

Another example of an ultrasonic device <NUM> is shown in <FIG>. Features of the device <NUM> that correspond to features on the device <NUM> shown in <FIG> are given like reference numbers but incremented by <NUM>.

The device <NUM> comprises a clamp <NUM> and one or more ultrasonic transducers (in this example a plurality of the ultrasonic transducers are provided in a plurality of ultrasonic transducer arrays <NUM>, which can be seen particularly in <FIG> and <FIG>) located in the clamp <NUM>. The ultrasonic transducer arrays <NUM> can be those shown and described in relation to <FIG>, for example, or as described in any of <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and/or <CIT>, all in the name of the present applicants.

Like the clamp <NUM> in the device <NUM> of <FIG>, the clamp <NUM> of <FIG> comprises a band <NUM>. However, a portion of the band <NUM> in the device <NUM> is formed from a conformable material such as an elastomer, preferably an elastomer capable of withstanding high temperatures, such as up to <NUM>, <NUM> or even <NUM>. Suitable elastomers could include, but are not limited to: fluoroelastomers; perfluoroelastomer; high temperature silicone blends and graphite based blends. The conformable nature of the device <NUM> allows it to operate without a couplant, such as a gel, thereby making it beneficial for high temperature and/or long term applications.

Specifically, the band <NUM> comprises a conformable material sub-band <NUM> formed from the conformable material and provided around a securing band <NUM>. The band <NUM> can be used to fasten the device <NUM> around the test object <NUM> and provide sufficient force for couplant free operation. The band <NUM> can be secured and tightened with a closure mechanism <NUM>. For example, the closure mechanism could comprise a ratchet mechanism, screw / bolt closure or worm gear arrangement, and/or the like. The securing band <NUM> is preferably formed from a suitably durable material such as metal, e.g. stainless steel.

The conformable material (e.g. the flexible elastomer) forming the conformable sub band <NUM> holds the ultrasonic transducers or transducer arrays <NUM>. The ultrasonic transducers or transducer arrays <NUM> can optionally be moulded into the conformable material or may be removable inserts. The conformable material is electrically insulating and a layer of the conformable material extends between the metal securing band <NUM> and the ultrasonic transducers or transducer arrays <NUM> and/or any electronics required to operate them. This arrangement may protect the ultrasonic transducers or transducer arrays <NUM> by distributing force evenly. This backing of conformable material also provides a degree of compensation for expansion/contraction of the test object with heating. The ultrasonic transducers or transducer arrays <NUM> could optionally have integrated wiring that could be moulded through the conformable material or channelled between the conformable sub-band <NUM> and the metal securing band <NUM>. Alternatively, the ultrasonic transducers or transducer arrays <NUM> could be fitted with a surface mount connector such as a microcoax allowing them to be hooked up with a separate wire for improved modularity.

As shown particularly in <FIG>, the device <NUM> could be produced in differing lengths for varying pipe diameters or as a long reel to be cut to length for improved customisation. Lengths of the device <NUM> could be produced with different spacings of ultrasonic transducers or transducer arrays <NUM> to allow for an optimal number of ultrasonic transducers or transducer arrays <NUM> and placement on a given diameter of test object <NUM>. Combining a reel system that can be cut to length, insertable ultrasonic transducers or transducer arrays <NUM> with the inherent mass manufacturable nature of the above arrangement could make the device <NUM> well suited to continuous monitoring on large infrastructure. In addition, the design of the device <NUM> may allow it to be made with a very low profile, if required. This would allow the device <NUM> to be deployed in tight confines such as close networks of piping and close to joints and corners. The low profile also makes the device <NUM> well suited to fitting under insulation in oil and gas pipeline applications with minimal disruption to the insulation design.

<FIG> illustrates a method of assembling or repairing the devices <NUM>, <NUM>, in which the one or more ultrasonic transducers <NUM>, <NUM> are provided in the device body <NUM> and/or the conformable sub-band <NUM> (step <NUM>) and mounted on the clamp <NUM> or securing band <NUM> (step <NUM>).

<FIG> illustrates a method of using the devices <NUM>, <NUM> in which the ultrasonic device <NUM>, <NUM> is fixed to the test object <NUM> using the clamps <NUM> (step <NUM>). Thereafter, the urging mechanism is adjusted to force the transducers array <NUM> onto the test object <NUM> (step <NUM>). This may involve rotating the screw <NUM> or by stretching the conformable sub bands <NUM>. Thereafter, the transducers <NUM> are driven using a drive signal to produce ultrasonic waves and are interrogated by a control device to receive output signals resulting from reflected ultrasonic waves being received by the transducers <NUM> (step <NUM>).

Although specific examples are described above in relation to the Figures, it will be appreciated that variations on the above examples are possible. As such, the scope of protection is defined by the claims and not by the above specific examples.

For example, although examples of piezoelectric materials being ZnO or AIN are given above, it will be appreciated that other piezoelectric materials could be used instead. Furthermore, although transition metal doped piezoelectric materials are described, it will be appreciated that non-doped piezoelectric materials could be used. In addition, although various thicknesses, dimensions, numbers and geometric arrangements of electrodes, conductive tracks and contacts are given above, it will be appreciated that other thicknesses, dimensions, numbers and geometric arrangements of electrodes, conductive tracks and contacts could be used. Indeed, although the electrodes are all shown as the same size and shape, it will be appreciated that at least some or all of the electrodes may be of different sizes and/or shapes.

Claim 1:
An ultrasonic device, the device comprising:
at least one flexible ultrasonic transducer (<NUM>);
a clamp (<NUM>) configured to mount the at least one transducer to a test object (<NUM>);
an urging mechanism (<NUM>) coupled to the at least one flexible transducer via a coupling (<NUM>), the urging mechanism being configured to urge the at least one transducer towards and/or onto the test object, in use; and
a device body (<NUM>), wherein the at least one flexible transducer and the urging mechanism are housed in or mounted on the device body.