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Patent Searching and Data


Title:
ADDITIVE MANUFACTURING METHOD AND APPARATUS
Document Type and Number:
WIPO Patent Application WO/2021/032699
Kind Code:
A1
Abstract:
Described is a method for in-situ enhancement of a structure (22). The method comprises positioning an additive manufacturing apparatus (20) in proximity of a target region to be enhanced, and enhancing the target region using the additive manufacturing apparatus to deposit an enhancing material (26) on a surface of the structure.

Inventors:
MCNAY GRAEME (GB)
MITCHELL ANDREW (GB)
Application Number:
PCT/EP2020/073032
Publication Date:
February 25, 2021
Filing Date:
August 17, 2020
Export Citation:
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Assignee:
AISUS OFFSHORE LTD (GB)
International Classes:
B23P6/00; B33Y30/00; E21B23/00; E21B41/06; E21B47/00; F16L55/162; F16L55/168; F16L55/18
Domestic Patent References:
WO2018236407A12018-12-27
WO2019104427A12019-06-06
Foreign References:
GB2562812A2018-11-28
US20180117718A12018-05-03
Attorney, Agent or Firm:
MARKS & CLERK LLP (GB)
Download PDF:
Claims:
CLAIMS:

1. A method for in-situ enhancement of a structure, the method comprising: positioning an additive manufacturing apparatus in proximity of a target region to be enhanced; enhancing the target region using the additive manufacturing apparatus to deposit an enhancing material on a surface of the structure.

2. The method according to claim 1 , wherein the target region comprises a defect, and the enhancing material comprises a repair material.

3. The method according to claim 1 or 2, comprising identifying a location of the target region by running an inspection tool into and/or adjacent to the structure.

4. The method according to any preceding claim, comprising producing a three- dimensional image of the structure to identify a target region thereof.

5. The method according to any preceding claim, comprising running the additive manufacturing apparatus adjacent the structure so as to position the additive manufacturing tool in proximity of the target region.

6. The method according to claim 5, comprising at least one of running the additive manufacturing apparatus inside the structure and running the additive manufacturing apparatus external to the structure.

7. The method according to any of claims 3 to 6, wherein the inspection tool is located on the additive manufacturing apparatus, and comprising identifying a target region of the structure and positioning the additive manufacturing apparatus in proximity of the target region in a single run adjacent the structure.

8. The method according to any preceding claim, comprising inspecting the integrity of the structure and logging information relating to the target region of the structure and providing the information for in-situ enhancement of the target region.

9. The method according to any preceding claim, comprising inspecting an enhanced region of the structure.

10. The method according to any preceding claim, wherein depositing the enhancing material on a surface of the structure comprises melting the enhancing material to deposit the enhancing material on the surface of the structure.

11. The method according to any preceding claim, comprising depositing the enhancing material directly onto the target region.

12. The method according to claim 11, comprising depositing a patch of enhancing material directly onto the target region and onto a surface of the structure surrounding the target region.

13. The method according to claim 11 or 12, comprising depositing a portion of the enhancing material on the surface of the structure axially downhole of the target region, to form a support volume to support enhancing material to be deposited directly onto the target region.

14. The method according to claim 11, comprising depositing a portion of the enhancing material on the surface of the structure uphole and downhole of the target region to form a first and a second support volume, and depositing a bridge of enhancing material between the first and second support volumes and directly onto the target region.

15. The method according to claim 14, wherein the first support volume is formed at an axially upward location in the structure, relative to the second support volume.

16. The method according to claims 14 or 15, wherein the bridge of enhancing material is in the form of a ring, collar or sleeve of material formed on the surface of the structure.

17. The method according to claims 14 or 15, wherein the bridge of enhancing material is either: in the form of a hollow truncated cone of material, or in the form of a half-sleeve.

18. The method according to claim 2 or any claim dependent thereon, wherein the defect comprises at least one of: a reduction in the thickness of a wall of the structure and an aperture extending entirely through a wall of the structure.

19. The method according to any preceding claim, wherein enhancing the target region comprises depositing enhancing material around the circumference of the target region, so as to form a patch of enhancing material over the target region.

20. The method according to any preceding claim, comprising depositing enhancing material on the surface of the structure to fortify the structure, or a section of the structure.

21. The method according to any preceding claim, comprising monitoring the enhancing material as the enhancing material is deposited onto the surface of the structure.

22. The method according to claim 21, wherein the monitoring comprises a closed feedback loop to alter characteristics of the deposit of enhancing material onto the surface of the structure.

23. The method according to any preceding claim, wherein the structure, or a part thereof, is located at least one of: subsea, in a splash-zone and above sea level.

24. The method according to any preceding claim, wherein the structure is a tubular.

25. An apparatus for performing the method of claim 1 , comprising: an arrangement housing a volume of enhancing material; an inspection tool; a depositing tool for depositing enhancing material on a surface of a structure.

26. A method for in-situ enhancement of a target region to be enhanced in a tubular, the method comprising: producing a three-dimensional image of a portion of the tubular to identify a target region to be enhanced therein; performing a preparation of a surface of the tubular adjacent the target region; enhancing the target region using an additive manufacturing apparatus to deposit an enhancing material on the prepared surface of the tubular.

Description:
Additive Manufacturing Method and Apparatus

FIELD

The described examples relate to methods and apparatus for in-situ enhancement of a structure, for example a repair of a defect in a structure (e.g. a tubular).

BACKGROUD

Across many industries, tubulars are used as a common means for transporting fluids and, in some cases, tooling or other equipment. In many cases the tubulars, as well as other offshore structures, are used over an extended period of time in harsh environments. As such, over time, said tubulars and offshore structures can be expected to degrade, perhaps a result of damage or corrosion.

The use of tubulars offshore, for example in an offshore hydrocarbon production structure, can require tubulars to be installed and used over a number of years. In addition to ensuring safe function of such tubulars, it is important to establish a high degree of structural integrity for reasons of cost and efficiency, as their use is often to transport fluids which are vital to ongoing operations.

As tubulars degrade over time, defects can appear in the walls thereof, compromising their structural integrity. As such tubulars, for example caissons, are regularly inspected to identify defects. Typically, this process involves an inspection operation followed by the necessary repair operations. During both the inspection and repair operations, it is necessary to cease use of the tubular in question until the operations are complete. As such, ongoing operations can experience a lengthy period of down time, which can be costly. Further, known methods of tubular/pipeline repair such as swaging or wrapping can themselves be costly, as well as time consuming. However, in order to protect the structural integrity of operational tubulars, this is a cost which must be borne. SUMMARY

An aspect of the present disclosure relates to a method for in-situ enhancement of a structure, the method comprising: positioning an additive manufacturing apparatus in proximity of a target region to be enhanced; and enhancing the target region using the additive manufacturing apparatus to deposit an enhancing material on a surface of the structure.

In one example, enhancing may comprise repairing a defect in the structure at the target region.

Thus, in one example the method relates to in-situ repair of a defect in a structure, the method comprising: positioning the additive manufacturing apparatus in proximity of the defect; and repairing the defect using the additive manufacturing apparatus to deposit the enhancing material on a surface of the structure.

In this example the enhancing material may define a repair material.

The target region may be a region of the structure requiring enhancing, for example due to the region comprising a defect or being likely to develop a defect in future, or for some other reason requiring the region to be enhanced. Enhancing may comprise repairing an existing defect in the structure.

The method may facilitate the in-situ enhancement (e.g., repair) of a structure by permitting an additive manufacturing apparatus to be positioned adjacent a structure (e.g. a caisson, tubular etc.), such that enhancement (e.g., repair) of the structure may be effected on-site, thereby removing the need to remove or replace the structure.

Enhancing the structure, such as repairing a defect in the structure, using an additive manufacturing apparatus may permit the enhancement (e.g., repair) to be made using less enhancing material than other methods, such as swaging. Further, use of an additive manufacturing apparatus to enhance a structure may be quicker than other methods, and therefore the user may make a saving in terms of time and money expended.

The structure may be a tubular. As such, the above example may relate to a method for in-situ enhancement (e.g. repair) of a defect in a tubular.

The tubular may be any conduit used for the transfer or transmission of a fluid or fluids. The structure, or at least a part thereof, may be located subsea. The structure, or at least a part thereof, may be located above sea level. For example, the structure may be located on the topsides of an offshore platform such as an oil rig. The structure, or at least a part thereof, may be located in a “splash-zone”, for example the splash-zone of an offshore platform, which may refer to the area immediately above and below the average water level on an offshore platform, caused by the rising and falling of the water level due to tidal fluctuations, for example. Where a structure, or a part thereof, is located in the splash zone, this part of the structure may therefore experience periods of time where it is located subsea and periods of time where it is located above sea level.

In one example the structure may be a caisson.

The structure may be a conductor, a riser, a j-tube or the like. The structure may be installed on an offshore platform, rig, or the like.

The structure may be part of a vessel, for example a hull of a vessel (e.g. a ship). As such, the above example, and where appropriate the examples below, may relate to a method for in-situ enhancement (e.g., repair) of a vessel (e.g. a hull of a vessel).

The structure may be part of a wind turbine. For example, the structure may be a support tripod of a wind turbine, a tower of a wind turbine, a pile connected to a wind turbine, or other structure providing support to a wind turbine. As such, the above example, and where appropriate the examples below, may relate to a method for in-situ enhancement (e.g., repair) of a wind turbine (e.g. a support tripod, tower, pile or other support structure forming part of or connected to a wind turbine). The structure may be part of other energy-generating systems. For example, the structure may be part of an energy-generating system for harnessing wave or tidal energy.

The method may comprise forming an object for enhancement of a structure. For example, the method may comprise forming an object to attach, mount, couple, or the like to a structure to enhance said structure. As such, the method may relate to the enhancement of a structure, and may not be restricted to the repair of a structure.

The method may comprise identifying a location of the target regions, for example a defect, in the structure. The method may comprise running an inspection tool into and/or adjacent to the structure so as to identify the location of the target region (e.g. a defect) in the structure. The method may comprise running the inspection tool on a wireline.

The target region (e.g. a defect) may be located at a portion of the structure that is subsea. The target region may be located at a portion of the structure that is above sea level. The target regions may be located at a portion of the structure that is in a splash- zone.

The method may comprise receiving information relating to the location of the target region (e.g. a defect) in the structure. The method may comprise using the received information to position the additive manufacturing apparatus in proximity of the target region.

The method may comprise running the additive manufacturing apparatus adjacent the structure so as to position the additive manufacturing tool in proximity to the target region. Running of the additive manufacturing apparatus may comprise at least one of running the additive manufacturing apparatus inside the structure (e.g. where the structure has a hollow interior as in the case of a tubular) and external to the structure. The method may comprise running a part of the additive manufacturing apparatus internal to the structure and a part of the additive manufacturing apparatus external to the structure. Running the additive manufacturing apparatus inside the structure may facilitate deployment of the additive manufacturing apparatus to a portion of the structure requiring enhancement (e.g. repair) without being impeded by external equipment or flanges which may be coupled to, or form part of, the structure. Running the additive manufacturing apparatus inside the structure may facilitate enhancement (e.g. repair) of a target region (e.g. a defect) therein by reducing or preventing external forces from acting on the manufacturing apparatus, for example drag forces that may act on the additive manufacturing apparatus as a result of fluid flow (e.g. tidal flow), or impact forces from sea/ocean waves, where the additive manufacturing apparatus is located subsea or in a splash-zone.

Running the additive manufacturing apparatus external to the structure may be more appropriate in cases, for example, where there is damage to the outside of the structure, or where it is not desired to apply enhancing material (e.g. repair material) to an inner surface of the structure, for example because a reduction in an inner dimension (e.g. inner diameter) is not desired.

The inspection tool may be located on the additive manufacturing apparatus, and the method may comprise both identifying a location of a target region (e.g. a defect) in the structure and positioning the additive manufacturing apparatus in proximity to the target region in a single run adjacent the structure. Such location of the inspection tool on the apparatus may therefore save time and cost associated with inspection and repair of a structure, as both may be completed in a single trip.

The method may comprise inspecting the integrity of the structure. The method may comprise logging or recording (e.g. in a memory component) information relating to the structure, for example a defect in the structure and/or the location of a defect in the structure. The method may comprise providing information for in-situ enhancement (e.g. repair) of the target region (e.g. a defect). For example the method may comprise providing information for in-situ enhancement (e.g. repair) to a user of the additive manufacturing apparatus, or providing information directly to the additive manufacturing apparatus. The information may be in relation to the structure, for example a defect in the structure, the location of the defect, the size of the defect, or the like. The method may comprise using the provided information to position the additive manufacturing apparatus adjacent a target region (e.g. a defect) in the structure.

The method may comprise transmitting data (e.g. information) to/from a data transmitter and receiver (e.g. a transceiver). The method may comprise transmitting data from the additive manufacturing apparatus to a surface location (e.g. to a user at a surface location). The method may comprise transmitting data from a surface location to the additive manufacturing apparatus. The transmitted data may relate to the location of the additive manufacturing apparatus, for example the axial location of the additive manufacturing apparatus relative to the structure.

The method may comprise transmitting data from a sensor arrangement on the additive manufacturing apparatus to a data receiver, and subsequently to a processor. The sensor arrangement may comprise a plurality of sensors, for example a visual sensor (e.g. a video camera), an ultrasound sensor and/or a laser profiler. The processor may be located on the additive manufacturing apparatus. The processor may be located at a surface location. The processor may be located at a subsurface location.

The method may comprise transmitting data from a processor to the additive manufacturing apparatus. The transmitted data may relate to the operation of the additive manufacturing apparatus, such as axial or rotational movement of the additive manufacturing apparatus (for example, to instruct the additive manufacturing apparatus or a component thereof to move axially or rotate within the structure). The method may comprise processing the transmitted data to locate the additive manufacturing apparatus adjacent a target region (a region to be enhanced, e.g. a defect) in the structure. The method may comprise axially moving or circumferentially rotating the additive manufacturing apparatus, or a part thereof, based on the transmitted data, and a known location of the additive manufacturing apparatus, to locate the additive manufacturing apparatus adjacent a target region (e.g. a defect) in the structure.

The transmitted data may relate to the nature of a target region (e.g. a defect) in the structure, for example the size or location of a defect at the target region. The transmitted data may provide a user with the information required to accurately operate the additive manufacturing apparatus. For example, the transmitted data may provide a user with the location of the additive manufacturing apparatus, and the location of a target region (e.g. a defect) in the structure, thus permitting a user to locate the additive manufacturing apparatus adjacent the target region.

The method may comprise inspecting an enhanced region (e.g. a repaired defect) in the structure. The method may comprise inspecting an enhanced region (e.g. a repaired defect) in the structure using the inspection tool. The method may comprise transmitting data relating to the enhanced region from the additive manufacturing apparatus to a user, and/or to a processor. The inspection tool may comprise the sensor arrangement.

The method may comprise depositing the enhancing material (e.g. a repair material) on a surface of the structure. The method may comprise melting the enhancing material to deposit the enhancing material on the surface of the structure. The method may comprise depositing the enhancing material on the surface of the structure via a three- dimensional (3D) printing process. The method may comprise melting the enhancing material via a welding process on a surface of the structure. In this case, the welding process may be considered a three-dimensional (3D) printing process. The method may comprise melting a portion of the structure, for example a portion of the structure that is localised to the location that the enhancing material is melted. The method may comprise melting the enhancing material and a localised portion of the structure to fuse the enhancing material to the structure.

The method may comprise at least one of: depositing an enhancing material (e.g. a repair material) on a surface of the structure, at least part of said surface being located subsea; depositing the enhancing material on a surface of the structure, at least part of said surface being located in a splash-zone; depositing the enhancing material on a surface of the structure, at least part of said surface being located above sea level. The method may comprise depositing an enhancing material (e.g. a repair material) on a structure that is installed on, for example, an offshore platform or rig.

The method may comprise using a welding tool to deposit enhancing material (e.g. repair material) onto a surface of the structure. The welding tool may be in the form of a welding arm extending radially from the centre of the additive manufacturing apparatus. The welding tool may comprise an auxiliary tool or tools. For example the welding tool may comprise the inspection tool and/or a surface preparation tool, for example, which is described in further detail below.

The method may comprise depositing the enhancing material directly onto the target region (e.g. a defect in the structure). The method may comprise depositing a patch of enhancing material directly onto the target region and onto a surface of the structure surrounding the target region. The method may comprise forming an object (e.g. a patch) of enhanced material (e.g. repair material) and subsequently depositing that patch onto the target region (e.g. the defect). As such, the method may comprise forming an object separately to the enhancing of the structure.

The method may comprise depositing a portion of the enhancing material (e.g. repair material) on the surface of the structure on one axial side of the target region (e.g. a downwardly located or downhole side, which may comprise a defect), to form a support volume to support the enhancement material to be deposited directly onto the target region. The method may comprise depositing a portion of the enhancement material both on the surface of the structure on a second axial side of the target region (e.g. an upwardly located or uphole side) and the first axial side of the target region to form a first and a second support volume, and depositing a bridge of enhancing material (e.g. repair material) between the first and second support volumes and directly onto the target region.

The first support volume may be formed at an axially upward location in the structure, relative to the second support volume. The bridge of enhancing material may be in the form of a ring, collar or sleeve of material formed on the surface of the structure (e.g. an internal surface of the structure). The bridge of enhancing material may be in the form of a hollow truncated cone of material. The bridge of enhancing material may be in the form of a half-sleeve.

The target region (e.g. a defect in the structure) may comprise a reduction in the thickness of a wall of the structure. The defect may extend entirely through a wall of the structure (e.g. in the form of an aperture extending entirely through a wall of the structure). The method may comprise enhancing the target region (e.g. repairing the defect) by depositing enhancing material (e.g. repair material) around the circumference of the target region, so as to form a patch of enhancing material over the target region.

The method may comprise depositing enhancing material on the surface of the structure to fortify the structure, or a portion of the structure. Fortification may relate to an increase in the strength and/or wall thickness of a structure. The method may comprise depositing enhancing material on the surface of the structure to protect the structure, or a portion of the structure, from damage. For example, the enhancing material may act as a physical barrier between the structure and an external environment.

The method may comprise monitoring the enhancing material (e.g. repair material) as the enhancing material is deposited onto the surface of the structure. The method may comprise using the sensor arrangement to monitor the enhancing material as the enhancing material is deposited onto the surface of the structure. The sensor arrangement may be located on the welding tool, e.g. the welding arm.

Where the enhancing material (e.g. repair material) is deposited onto a surface of the structure via a welding process, a visual sensor may be used to measure the weld shape, size and depth. A laser profiler may be used to measure the weld shape, size and depth. An ultrasound sensor may be used to measure the weld thickness and depth. The method may comprise depositing enhancing material onto a surface of the structure using a welding process, and monitoring at least one parameter of a weld, which may be one of the weld shape, size, depth and thickness.

The method may comprise producing a three-dimensional (3D) image of at least a portion of the structure, for example to identify a target region (e.g. a defect) therein. The method may comprise using the sensor arrangement to compose a three- dimensional (3D) image of a portion of the structure, for example a target region (e.g. a defect) and/or an enhanced portion (e.g. a repaired portion) of the structure.

The method may comprise transmitting data relating to at least one parameter of a weld to a processor, wherein the processor comprises a control system. The method may comprise comparing data relating to at least one parameter of a weld to an expected value, or range of values. The method may comprise using the control system, located in the processor, to compare data relating to at least one parameter of a weld to an expected value, or range of values. Based on a comparison of data relating to a least one parameter to an expected value, or range of values, the method may comprise configuring the control system to transmit data (e.g. an instruction) via a data transmitter, to the additive manufacturing apparatus to alter a characteristic of the welding process, for example the rate of use of enhancing material (e.g. repair material), the location at which the enhancing material is applied, the size of the weld pool, the positioning of the weld pool, or the like. In other similar words, the method may comprise a closed feedback loop to alter characteristics of the deposit of enhancing material onto the surface of the structure. In this way, the method may allow real-time updating and/or adaptation of the welding process to suit the specifics of geometry of the target region (e.g. a defect) and structure. As such, the method may permit a degree of machine learning, whereby the process of welding is adapted and optimised to fit the specific geometry of the target region and structure.

The method may comprise preparing a surface of the structure for depositing enhancing material (e.g. repair material) thereon. Preparing a surface of the structure may comprise cleaning the surface of the structure, for example cleaning an interior or exterior surface of the structure. The method may comprise jetting a surface of the structure with a cleaning fluid such as water and/or a surfactant, e.g. a detergent.

The method may comprise using the additive manufacturing apparatus to prepare a surface of the structure for depositing enhancing material (e.g. repair material) thereon. The additive manufacturing apparatus may comprise a surface preparation tool for this purpose. For example, the welding tool of the additive manufacturing apparatus may comprise the surface preparation tool. Alternatively, the surface preparation tool may be located uphole or downhole on the apparatus (e.g. above or below) relative to the welding tool.

The method may comprise using a preparation tool to prepare a surface of the structure for depositing enhancing material (e.g. repair material) thereon. For example, the method may comprise using a preparation tool to clean a surface of the structure. The preparation tool may comprise a fluid jet, and/or may comprise a scrubbing tool, such as a brush. The method may comprise running a preparation tool into or adjacent (e.g. externally of) the structure to prepare a surface of the structure, and subsequently withdrawing the preparation tool, before running the additive manufacturing apparatus into or adjacent (e.g. externally of) the structure.

The method may comprise using a preparation tool to prepare a surface of the structure after depositing enhancing material (e.g. repair material) thereon. For example, the method may comprise using a preparation tool to remove material from a surface of the structure, such as welding flux, or excess enhancing material such as excess welding wire.

The method may comprise ceasing operation of equipment positioned inside the structure (e.g. tubular). For example, the method may comprise ceasing operation of a pump, configured to pump a fluid through a structure.

An aspect of the present disclosure relates to apparatus for performing the method, the apparatus comprising: an arrangement housing a volume of enhancing material; an inspection tool; a depositing tool for depositing enhancing material on a surface of a structure.

The arrangement may be in the form of a structure, for example a housing and/or a framework.

In one example, the enhancing material may be configured to repair a defect in the structure. In such an example, the enhancing material may define a repair material.

The inspection tool may extend in a radial direction from the arrangement. For example, the inspection tool may extend from the arrangement in the form of an arm. The inspection tool may comprise a sensor arrangement. The sensor arrangement may comprise at least one of a visual sensor (e.g. a video camera), a laser profiler and an ultrasound scanner. The sensor arrangement may function to provide a three- dimensional image of an inspected portion of the structure, for example a target region, a defect, or an area of defect, of the structure.

The inspection tool may comprise a plurality of arms extending from the arrangement. The sensor arrangement may be located on at least one, or all, of the plurality of arms. Each of the plurality of arms may comprise at least one of a visual sensor, a laser profiler and an ultrasound scanner.

The depositing tool may extend in a radial direction from the arrangement. For example, the depositing tool may extend from the arrangement in the form of an arm. The depositing tool may comprise a welding tool. A volume of enhancing material (e.g. repair material) may be fed from the arrangement to the depositing tool. For example, a volume of enhancing material may be fed from the arrangement and to the welding tool via the arm of the depositing tool.

The apparatus may comprise a surface preparation tool. The surface preparation tool may be used to prepare a surface of the structure prior to depositing of an enhancing material (e.g. a repair material) thereon. The surface preparation tool may be used to prepare a surface of the structure after depositing of an enhancement material (e.g. a repair material) thereon, for example to remove unwanted material (e.g. welding flux, additional enhancing material such as welding wire, or the like). The surface preparation tool may extend in a radial direction from the arrangement. The surface preparation tool may extend from the arrangement in the form of an arm. The surface preparation tool may comprise a nozzle. The surface preparation tool may function to provide a jet of fluid, for example a jet of washing fluid. The surface preparation tool may be in communication with a source of washing fluid. The washing fluid may be or comprise water. The washing fluid may be or comprise a surfactant, for example a detergent.

At least one of the inspection tool, the depositing tool and the surface preparation tool may be located on a single arm of the apparatus.

The surface preparation tool may comprise a scrubbing component, for example a brush. The scrubbing component may be radially moveable relative to the apparatus. Radial movement of the scrubbing component may permit the scrubbing component to be moved into and out of contact with a surface of the structure. The scrubbing component may assist to prepare the surface of a structure before and/or after the depositing of an enhancing material (e.g. a repair material) thereon. An aspect of the present disclosure relates to a method for in-situ enhancement of a target region to be enhanced in a tubular, the method comprising: producing a three-dimensional image of a portion of the tubular to identify a target region to be enhanced therein; performing a preparation of a surface of the tubular adjacent the target region; enhancing the target region using an additive manufacturing apparatus to deposit an enhancing material on the prepared surface of the tubular.

In one example, enhancing may comprise repairing a defect in the structure at the target region. In this example, the enhancing material may define a repair material.

Enhancing may comprise repairing an existing defect in the structure. Enhancing may comprise enhancing a target region, which may be a region requiring enhancing, for example due to the region comprising a defect or being likely to develop a defect in future, or for some other reason requiring the region to be enhanced.

An aspect of the present disclosure relates to a method for in-situ repair of a defect in a structure, the method comprising: positioning an additive manufacturing apparatus in proximity of the defect; repairing the defect using the additive manufacturing apparatus to deposit a repair material on a surface of the structure.

The method may comprise identifying a location of the defect in the structure by running an inspection tool into and/or adjacent to the structure.

The method may comprise producing a three-dimensional image of the structure to identify a defect therein.

The method may comprise running the additive manufacturing apparatus adjacent the structure so as to position the additive manufacturing tool in proximity to the defect.

The method may comprise at least one of running the additive manufacturing apparatus inside the structure and running the additive manufacturing apparatus external to the structure. The inspection tool may be located on the additive manufacturing apparatus.

The method may comprise identifying a location of a defect in the structure and positioning the additive manufacturing apparatus in proximity to the defect in a single run adjacent the structure.

The method may comprise inspecting the integrity of the structure and logging information relating to the location of a defect in the structure and providing the information for in-situ repair of the defect.

The method may comprise inspecting a repaired defect in the structure.

Depositing the repair material on a surface of the structure may comprise melting the repair material to deposit the repair material on the surface of the structure.

The method may comprise depositing the repair material directly onto the defect.

The method may comprise depositing a patch of repair material directly onto the defect and onto a surface of the structure surrounding the defect.

The method may comprise depositing a portion of the repair material on the surface of the structure axially downhole of the defect, to form a support volume to support repair material to be deposited directly onto the defect.

The method may comprise depositing a portion of the repair material on the surface of the structure uphole and downhole of the defect to form a first and a second support volume, and depositing a bridge of repair material between the first and second support volumes and directly onto the defect.

The first support volume may be formed at an axially upward location in the structure, relative to the second support volume.

The bridge of repair material may be in the form of a ring, collar or sleeve of material formed on the surface of the structure. The bridge of repair material may be either: in the form of a hollow truncated cone of material, or in the form of a half-sleeve.

The defect may comprise at least one of: a reduction in the thickness of a wall of the structure an aperture extending entirely through a wall of the structure.

Repairing the defect may comprise depositing repair material around the circumference of the defect, so as to form a patch of repair material over the defect.

The method may comprise depositing repair material on the surface of the structure to fortify the structure, or a section of the structure.

The method may comprise monitoring the repair material as the repair material is deposited onto the surface of the structure.

The monitoring may comprise a closed feedback loop to alter characteristics of the deposit of repair material onto the surface of the structure.

The structure, or a part thereof, may be located at least one of: subsea, in a splash- zone and above sea level.

The structure may be a tubular.

An aspect of the present disclosure relates to an apparatus for performing the method described above, comprising: an arrangement housing a volume of repair material; an inspection tool; a depositing tool for depositing repair material on a surface of a structure.

An aspect of the present disclosure relates to a method for in-situ repair of a defect in a tubular, the method comprising: producing a three-dimensional image of a portion of the tubular to identify a defect therein; performing a preparation of a surface of the tubular adjacent the defect; repairing the defect using an additive manufacturing apparatus to deposit a repair material on the prepared surface of the tubular.

Features defined in relation to one aspect or example may be provided in accordance with any other aspect of example described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1 is a schematic illustration of an offshore oil rig.

Figure 2 is a schematic illustration of an additive manufacturing apparatus positioned in a structure.

Figures 3a and 3b are schematic illustrations of two exemplary additive manufacturing apparatuses positioned in a structure.

Figures 4a and 4b are schematic illustrations of a repaired structure showing two exemplary additive manufacturing apparatuses therein.

Figures 5a to 5d are schematic plan views of exemplary additive manufacturing devices positioned in a structure.

Figures 6a and 6b illustrate an additive manufacturing device positioned on an outer surface of a structure.

Figures 7a to 7d show various views of a repaired defect in a structure.

Figures 8a to 8c illustrate the repair of a structure.

DETAILED DESCRIPTION OF THE DRAWINGS The present disclosure relates to a method and apparatus that may be used in a variety of applications. In the description that follows, example forms of the apparatus are presented without any intended restriction on the application or use of the apparatus, although some examples of potential operations that could be performed using the apparatus will be suggested, and one specific example use of the apparatus will be provided.

Figure 1 shows a schematic illustration of an offshore oil platform 5, showing a body of water 10 in which the oil platform 5 is located. The topsides 12 of the oil platform comprise legs 14, which extend from the topsides 12, and support the oil platform 5 subsea.

Running vertically from the topsides 12 of the oil platform 5 and into the body of water 10 is a structure 16, which in this example is a tubular and may be a caisson or a conductor.

In use, the structure 16 (e.g. the caisson) may be used to transport fluids, such as water, to the topsides 12 for various uses, for example for use as a coolant. To facilitate the transport of fluids to the topsides 12, in this example the structure 16 comprises a pump 18, located in a portion of the structure 16 that is submerged in the body of water 10.

Over time, the structure 16 may become damaged, for example due to prolonged use of the structure 16, or because of the harsh environment in which the structure 16 is used. Damage to the structure 16 may manifest itself in the form of cracks or holes in the structure 16. Additionally or alternatively, damage to the structure 16 may be in the form of a reduction in the wall diameter of the structure 16, for example due to pitting corrosion of the structure 16. In order to maintain the functionality of the structure 16, it is necessary to intermittently monitor the structure 16, and repair any damage that may affect the integrity of the structure 16.

Figure 2 is a schematic illustration of an additive manufacturing apparatus 20 positioned in a structure22, which in this case may be a tubular or may be another hollow structure as may be found on an offshore platform, for example. The illustration in Figure 2 shows only a small section of a structure 22. The structure 22 may be a caisson, as described in relation to Figure 1. The section of structure 22 may be located subsea, or in a splash-zone of an offshore platform. Alternatively, the section of structure 22 may be located above sea level, for example on the topsides of an offshore platform.

In the illustration of Figure 2, the additive manufacturing apparatus 20 comprises a welding tool 24 and welding material 26. In this case, the welding tool 24 is in the form of a welding arm, and the welding material 26 is in the form of a spool of wound material, for example wound mild steel, stainless steel, or the like.

As illustrated, the welding tool 20 of the additive manufacturing apparatus 20 is located inside the structure 22, and the additive manufacturing apparatus 20 may be used to deposit material on an interior surface 28 of the structure 22. One method for doing so, as is the case in Figure 2, is by depositing the welding material 26 onto the inner surface of the structure 22 via a welding process. The welding process may be a MIG welding process, a MAG welding process, or the like.

The welding material 26 is in communication with the welding tool 24, such that the welding material 26 can be fed to the welding tool 24 in use. In some cases, the welding material 26 may form a wire electrode, such that flow of electric current between the welding material 26 and the structure 22 establishes sufficient heat to enable melting and depositing of the welding material 26 on the interior surface 28 of the structure 22.

The welding tool 24 may be axially rotatable relative to the additive manufacturing apparatus 20. In this example, an axis 32 of the structure 22 is illustrated, and the welding tool 24 may be rotatable around axis 32, or an axis running parallel thereto. In rotating around axis 32, the additive manufacturing tool 20 may be used to deposit the welding material around a circumferential portion of the structure 22, which will be described in more detail in further Figures.

In this example, the additive manufacturing apparatus 20 is suspended in the structure 22 via a cable 30. In use, the cable 30 may be in the form of a wireline, and may comprise a structural component and optionally a data transfer component, such as copper wire or optical fibre, which may used to control operation of the additive manufacturing apparatus 20. The cable 30 is connected to a control unit 34, which may control the payout of the cable 30, and therefore the deployment of the additive manufacturing apparatus 20 in the structure 22.

Shown in Figure 2, the control unit 34 comprises a data transceiver 36 and a processor 38 for processing the data from the data transceiver 36. The data transceiver 36 may receive data from a user, for example data relating to the location of a defect in structure 22, and/or may receive data from the additive manufacturing apparatus 20. In one example, the received data may relate to the positioning of the additive manufacturing apparatus 20 in the structure 22, and/or may relate to the application of the repair material to the interior surface 28 of the structure 22. The received data may be transmitted to the additive manufacturing apparatus 20, and may be used to control the operation of the manufacturing apparatus 20. For example, the received data may be used to control the payout of the cable 30 by the control unit 32, and therefore control the axial position of the manufacturing apparatus 20 in the structure 22. The received data may be used to control the rotation of the welding tool 24, for example the degree of rotation, the speed of rotation, or the like. The received data may be used to control the application of repair material to the interior surface 28 of the structure 22, for example the volume of repair material applied, the speed of application, or the like.

The received data, or a portion thereof, may be transmitted to the additive manufacturing apparatus 20 via the cable 30, for example via a data transfer component of the cable 30 such as an optical fibre. Additionally or alternatively, the received data, or a portion thereof, may be transmitted to the additive manufacturing apparatus 20 wirelessly, as indicated by the broken line 25.

The additive manufacturing apparatus 20 also comprises a processor 40. The processor 40 may receive instructions from the control unit 34, as well as providing data thereto. For example, the processor 40 may receive instructions for controlling movement of the welding tool 24, for example circumferential movement of the welding tool. Controlling the movement of the welding tool 24 may relate to the magnitude of circumferential movement of the welding tool 24, the speed of movement, the location of a start and end point of movement, or the like. Additionally, the processor 40 may provide the control unit 34 information on the location of the additive manufacturing apparatus 20. Although not shown in Figure 2, the additive manufacturing apparatus 20 may comprise a sensor arrangement. For example, the additive manufacturing apparatus 20 may comprise any such sensors or devices necessary to provide the relevant data regarding the location of the apparatus 20 when in a structure. The additive manufacturing apparatus 20 may comprise a visual sensor such as a camera for providing information on the immediate surroundings of the additive manufacturing apparatus, for example, allowing an inspection of the immediate surroundings. Additionally or alternatively, the additive manufacturing apparatus 20 may comprise an accelerometer and/or a gyroscope for determining the orientation of the apparatus 20 in the structure.

In this example, the additive manufacturing apparatus 20 is suspended in the structure 22 so as to be axially aligned with the axis 32 of the structure 22. However, the skilled person will understand that in some examples the additive manufacturing apparatus 20 may be suspended misaligned with the axis 32 of the structure 22.

The additive manufacturing apparatus 20 may comprise such monitoring sensors or devices necessary to ensure correct application of the repair material to the interior surface 28 of the structure 22. For example, the additive manufacturing apparatus 20 may comprise a visual sensor. Where the repair material is applied to the interior surface 28 by the welding tool 24, the visual sensor may provide visual feedback (e.g. to a user) of characteristics of the weld such as the weld shape, size and/or depth. The additive manufacturing apparatus 20 may also or alternatively comprise a laser profiler, which may provide feedback on the characteristics of the weld such as the weld shape, size and/or depth. The additive manufacturing apparatus 20 may also or alternatively comprise an ultrasound sensor, which may provide feedback on the characteristics of the weld such as thickness and/or depth. Although not shown, such monitoring sensors or devices may be installed on the welding tool 24.

Having monitoring sensors or devices, as described above, may assist the manufacturing apparatus 20 to more accurately control the application of repair material to the interior surface 28 of the structure 22. For example, where a welding tool 24 is used, monitoring sensors or devices may permit control of characteristics of the weld, such as permit control of the weld pool, the positioning of the weld pool and the volume of repair material that is deposited on the interior surface 28 of the structure. The monitoring sensors may transmit data to the data transceiver 36, which may be transmitted via the cable 30 and/or wirelessly, as indicated by the broken line 25. In this case, the processor 40 may comprise a control system incorporating a feedback loop (e.g. a closed feedback loop). The feedback loop may involve the processor 40 receiving data from the monitoring sensors, which may relate to the characteristics of a weld, and comparing this data against an expected value or range of values. The processor 40 may then transmit instructions (via the data transceiver 36) to the additive manufacturing apparatus 20 to control its operation, which may relate to the rate of deposit of repair material, and/or the positioning, shape, size, depth, thickness, or the like, of the repair material (e.g. the weld). As such, the additive manufacturing apparatus 20 may be able to control characteristics of the application of repair material (e.g. the weld) real-time. The control system may be considered as machine learning, as it may enable the additive manufacturing apparatus 20 to adapt and optimise the application of repair material to the interior surface 28 of the structure 22 to the specific geometry of the structure 22.

Figures 3a and 3b are schematic illustrations of two exemplary additive manufacturing apparatuses 120 positioned in a tubular 122 (although the skilled person would readily understand that the additive manufacturing apparatuses may equally be placed as such in any hollow structure). In both Figures, the additive manufacturing apparatuses 120 are positioned adjacent a defect 150 in the tubular 122.

In Figure 3a, the additive manufacturing apparatus 120 comprises a welding tool 124, which can be used to deposit a welding material (not shown) onto an interior surface of the tubular 122. As was the case in the previous Figure, the tubular 122 may be located subsea, in a splash-zone or above sea level. In use, the welding tool 124 may be rotated around an axis of the additive manufacturing apparatus 120 (as described with reference to Figure 2) to deposit welding material circumferentially around the tubular, which in this example is circumferentially around the interior surface of the tubular 122. In addition to depositing welding material circumferentially around the interior surface of the tubular 122, the additive manufacturing apparatus 120 may also be used to deposit material in an axial direction, for example by lowering or lifting the apparatus 120 inside the tubular 122. Such lowering or lifting of the apparatus 120 may be accomplished by lowering/lifting the apparatus 120 via a cable 130 on which the apparatus 120 is suspended in the tubular 122. As in the previous Figure, the cable 130 may be a wireline, and may comprise a structural component for supporting the weight of the apparatus 120 in the tubular, and optionally a data transfer component for the transfer of data to and from the apparatus 120.

The apparatus 120 may be lifted/lowered at the same time as the welding tool 124 is rotated about the axis of the welding tool 124, enabling welding material to be deposited over a large area of the internal surface of the tubular 122.

In one example of Figure 3b, the additive manufacturing apparatus 120 comprises a sensor arrangement positioned on sensor arms 142a, 142b. The sensor arrangement may be used to inspect the tubular 122, for instance may be used to inspect the tubular 122 before and/or after a defect has been repaired. The sensor arrangement may comprise at least one of a visual sensor such as a video camera, an ultrasound transceiver, a laser profiler or the like.

The example of Figure 3b comprises a sensor arrangement having a sensor positioned both axially uphole and axially downhole of the welding tool 124. In this case, one sensor is positioned on axially uphole arm 142a, with another sensor being positioned on axially downhole arm 142b, although the skilled person would readily understand that other configurations would be possible - for example more than one sensor uphole and/or downhole of the welding tool may be equally possible. Having at least one sensor axially uphole and at least one sensor axially downhole of the welding tool 124 may permit a user to inspect the defect 150 both before and after a repair. For example, if lowering the additive manufacturing apparatus 120 into a wellbore, a user may inspect the defect 150 using the downhole sensor arm 142b, before moving the additive manufacturing apparatus 120 axially downhole to so as to position the welding tool 124 adjacent the defect 150 and repair the defect 150, and finally move the additive manufacturing apparatus 120 further downhole to inspect the repaired defect 150, for example to ensure that the repair has be completed successfully. Should more work be required to complete the repair, it may be possible to realign the defect 150 with the welding tool 124 to perform a further repair process.

It should be noted that, while in the example of Figure 3b, a sensor arrangement is shown on sensor arms 142a, 142b, other or additional tools may equally be mounted on the additive manufacturing apparatus 120. For example, a surface preparation tool may be mounted on the additive manufacturing apparatus 120, and may be incorporated into the welding arm 124 and/or the sensor arms 142a, 142b. The surface preparation tool may be in the form of a liquid jet, for example a water jet, and may be used to wash the surface before application of the repair material. Additionally or alternatively, the surface preparation tool may be in the form of a scrubbing component, such as a brush. In other examples, the surface preparation tool may be included on an additional arm extending from the additive manufacturing apparatus 120, in a similar way to the sensor arms 142a, 142b. The surface preparation tool may be located uphole or downhole of the welding arm 124, which may facilitate washing and/or scrubbing of a surface of the tubular 122 prior application of the repair material. Equally, the surface preparation tool may facilitate washing and/or scrubbing of a surface of the tubular 122 after application of the repair material. This may, for example, assist to remove unwanted material from the repaired defect, which may be in the form of welding flux and/or excess repair material, such as excess or stuck welding wire.

The additive manufacturing apparatus 120 may be used to repair the defect 150 by depositing welding material over the area of the defect 150. Figures 4a and 4b illustrate the additive manufacturing apparatus 120 located in a tubular 122, having been operated to repair the defect 150 in the tubular 122.

In this instance, the additive manufacturing apparatus 120 has been operated so as to deposit welding material 126 onto the interior surface of the tubular 122. The welding material 126 has been deposited around the entire circumference of the interior surface of an axial portion of the tubular 122 immediately surrounding the defect 150. In this case, welding material 126 is first deposited circumferentially onto the interior surface of the tubular 122 below (e.g. downhole of) the defect 150, for example by rotation of the welding tool 124 relative to the additive manufacturing apparatus 120, as previously described. As such, a lower ring of welding material 126 is formed downhole of the defect 150, which is shown in Figure 4b as 126a.

Once the lower ring 126a has been deposited in the tubular 122, an intermediate ring 126b of welding material is deposited, which is located above (e.g. uphole of) the lower ring 126a. The intermediate ring 126b covers the defect 150, and in this case assists to plug the defect 150, as well as an axial section of the interior surface of the tubular 122 in the immediate vicinity of the defect 150.

Upper ring 126c is then formed above (e.g. uphole of) the defect and both the intermediate ring 126b and the lower ring 126a. As with the lower and intermediate rings 126a, 126b, the upper ring covers the entire circumference of an axial portion of the inner surface of the tubular 122.

As is evident from Figures 4a and 4b, in this example the width of the upper and lower rings 126c, 126a is greater than that of the intermediate ring 126b. In providing this configuration, the thicker lower ring 126a may be used to provide structural support to the intermediate ring 126b as the welding material forming the intermediate ring 126b is being deposited inside the tubular 122. Further, a thicker upper and lower ring 126a, 126c may provide structural support to the underlying tubular and, for example assist to prevent propagation of any fissures from the defect 150, after the repair has taken place.

Schematically illustrated in Figures 5a to 5d are views of an additive manufacturing apparatus 220. In Figures 5a to 5c, the additive manufacturing apparatus 220 comprises a welding tool 224, which is able to rotate in a circumferential direction about a central axis of the additive manufacturing apparatus 220, for example in the direction of arrow 252. Alternatively or in addition, the additive manufacturing apparatus 220 itself may be moved in the direction of arrow 252 so as to provide circumferential rotation of the welding tool 224 inside the tubular 222.

In Figure 5a, the additive manufacturing apparatus 220 is located in the tubular 222 with the welding tool 224 positioned adjacent a defect 250, prior to repair of the defect 250. In contrast to previous Figures, in this case the defect does not extend entirely through the tubular, and instead is a section of tubular 222 having a reduced thickness. Such reduced thickness may be caused, for example, by pitting corrosion of the material of the tubular 222.

Figures 5b and 5c show two alternative repairs of the defect 250 in the tubular 222. In Figure 5b, a localised repair of the defect 250 is provided. Such localised repair involves providing a patch of welding material 226 on the interior surface of the tubular 222, which covers the location of the defect 250 as well as the interior surface of the tubular 222 immediately surrounding the defect 250. A localised repair may be preferable in cases where the defect is very small, or may be useful as a preventative measure against the formation of defects in a region of the tubular where defect formation may be particularly likely.

Figure 5c illustrates a repair of the defect 250 involving depositing welding material 226 around the entire circumference of an axial section of the tubular 222 in the vicinity of the defect 250, as also shown in the example of Figures 4a and 4b. In such an example, the welding tool 224 is rotated in the direction of arrow 252 to deposit welding material 226 circumferentially around the interior surface of the tubular 222, thereby covering the defect. Such a repair may be preferable in cases where the defect 250 is larger, and/or there may be risk of propagation of fissures from the defect, as the additional welding material 226 may assist to fortify the surrounding tubular 222. In some cases, this method of repair may be useful as a preventative measure against the formation of defects, where there is a large area of the interior of a tubular 222 in which defects may be likely to form.

Figure 5d schematically illustrates a further example of the additive manufacturing apparatus 220, comprising a plurality of welding tools 224, in this case four welding tools. As shown, the welding tools 224 are evenly circumferentially distributed around the additive manufacturing apparatus 220, although the skilled person will appreciate that other numbers and distributions of welding tools 224 are possible - for example 2, 3, or 5 welding tools, and an uneven or one-sided distribution may be possible.

In the configuration shown in Figure 5d, the additive manufacturing apparatus 220 may be able to deposit welding material 226 from each of the welding tools simultaneously, thereby reducing the time taken to deposit welding material on the interior surface of the tubular. A user may be able to rotate each of the welding tools 226 relative to the additive manufacturing apparatus 220, or indeed rotate the additive manufacturing apparatus 220 itself, to ensure circumferential coverage of the welding material 226 on the interior surface of the tubular 220.

Figure 6 illustrates an example of an additive manufacturing apparatus 320 that may be positioned internally relative to a structure (not shown). In this example, the additive manufacturing apparatus comprises a welding tool 354. The welding tool 354 may optionally comprise a monitoring sensor or sensors, for example a described in relation to Figure 2. In this example, the additive manufacturing apparatus 320 also comprises a number of contact arms 356 that, in use, would contact the interior surface of a structure, thereby assisting to centre the additive manufacturing apparatus 320 in the structure. Each contact arm 356 comprises a number of wheels 358, axially aligned with the structure so as to provide rolling contact between the additive manufacturing apparatus 320 and the structure, thereby facilitating axial movement of the additive manufacturing apparatus 320 along the structure.

Figures 7a and 7b illustrate an example of an additive manufacturing apparatus 420 positioned externally relative to a tubular 422, although the skilled person will understand that the additive manufacturing apparatus 420 could equally be positioned relative to a structure that is not a tubular. In this example, a support structure 454 may be required to position the additive manufacturing apparatus 420 relative to the tubular 422. As in the previous examples, the additive manufacturing apparatus 420 comprises a welding tool 424, which may be positioned adjacent a defect (not shown in this example) in the tubular 422. Although not shown in this example, the additive manufacturing apparatus 420 may also comprise additional components, such as a sensor arrangement and a surface preparation tool, as illustrated in previous Figures. As shown, the support structure 454 circumscribes the tubular 422. Contact arms 456 extend from the support structure 454 and contact the external surface of the tubular 422 so as to centre the support structure 454 around the tubular 422 and thereby assist to position the additive manufacturing apparatus 420 relative to the tubular 422.

To facilitate axial movement of the additive manufacturing apparatus 422 and the associated support structure 454 along the tubular 422, the contact arms 456 each comprise a wheel 458, which is axially aligned with the tubular, and thereby provides axial rolling contact between the support structure 454 and the tubular 422.

To facilitate circumferential movement of the additive manufacturing apparatus 422 relative to the tubular 422, in this example the support structure 454 and additive manufacturing apparatus 420 comprise a rack and pinon arrangement 460 extending circumferentially around the tubular 422. Although not shown, the additive manufacturing apparatus 422 may comprise a motor (e.g. an electrical motor) that is coupled to a pinion, thereby enabling propulsion of the additive manufacturing apparatus 420 relative to the rack of the support structure 454.

Figures 8a to 8d further illustrate a tubular 522 comprising a defect 550 that has been repaired through use of the additive manufacturing apparatus (not shown). In this case, the defect 550 extends through the entire thickness of the wall of the tubular 522, and as such repair material 526 can be seen on the outer surface of the tubular 522.

As can be seen most clearly in Figures 8b and 8c, a localised repair has been applied to the defect 550 in the form of a rectangular patch of repair material 8c, which fills the defect 550 and also adheres to the interior wall of the tubular 522 immediately surrounding the defect 550. In order to fill the defect 550 with welding material 526 it may be preferable to deposit the welding material 526 in the defect 550 in stages, so as to gradually close the defect 550 in the tubular 522. For example, welding material may be deposited around the periphery of the defect 550 in various stages, with each stage closing the defect 550, until the defect is completely closed.

Figures 9a to 9c show an example of the repair of a tubular 622 using the additive manufacturing apparatus shown in Figures 7a and 7b. In Figure 9a, the tubular 622 shows a section having a defect 650 therein, and a flow of fluid from the defect. The defect may be caused, for example, by a weld that has failed or has been improperly applied.

In Figure 9b, the defect 650 has been repaired by applying a repair material 626 to the exterior of the tubular 622. As can be seen, the repair material 626 has stopped the flow of fluid from the defect 650 and results in a slightly increased diameter of the repaired section of the tubular 622.

Figure 9c illustrates a tubular 622, also showing repair material 626 deposited along an exterior section of the tubular 622. In this case, the repair material 626 has been deposited along a longer section of the tubular 622 than in Figure 9b, and also incorporates a bend in the tubular 622. As shown in Figures 7a and 7b, the additive manufacturing apparatus may be mounted on the external surface of a tubular 622, which may permit the additive manufacturing apparatus to move axially with the geometry of the tubular, which in this case incorporates a bend.