GB2575707A

GB2575707A - Apparatus and method

Info

Publication number: GB2575707A
Application number: GB1906739.6A
Authority: GB
Inventors: Bathgate Douglas
Original assignee: Rovological Ltd
Current assignee: Rovological Ltd
Priority date: 2018-05-14
Filing date: 2019-05-13
Publication date: 2020-01-22
Also published as: GB201807809D0; GB201906739D0

Abstract

Apparatus 100 for operatively connecting a galvanic anode 108 to a metal structure 120 for corrosion protection is described. The apparatus has a first coupling portion 101for coupling the apparatus 100 to a metal structure 120. The apparatus 100has a second coupling portion to couple the apparatus to the galvanic anode. The first coupling portion comprises a resilient biaser 102 to be actuated by the metal structure 120 to thereby couple the first coupling portion 101 to the metal structure 120and electrically connect the second coupling portion 107 to an electrically connecting portion of the metal structure 120. The resilient biaser 102 comprises at least one resiliently deformable member 104 to be deformed by the metal structure to thereby couple the first coupling portion to the metal structure 120. The resilient biaser 102 may comprise a compression helical spring or a coil spring. The apparatus 100 can be deployed using an unmanned underwater vehicle (UUV) and the UUV may be a remotely operated vehicle (ROV).

Description

APPARATUS AND METHOD

Field of the Invention

The present disclosure relates to corrosion protection for a metal structure. More particularly, the present disclosure relates to an apparatus and a method for delivering a galvanic anode to a metal structure to provide corrosion protection to the metal structure.

Background of the Invention

Underwater pipelines for use e.g. in the oil and gas industry are generally supported by structures formed of metals such as steel, which may be subject to corrosion. Corrosion protection for metal supporting structures can be provided by applying cathodic corrosion protection techniques that connect a sacrificial metal anode to the supporting structure in order to form an electrochemical cell, where the sacrificial metal is preferentially corroded in favour of the metal of the supporting structure.

It may be that changing demands for pipeline usage require that the pipeline supporting structures be adapted or upgraded, e.g. to provide support for the addition of secondary pipelines. In this case it may be advantageous to retro-fit any of the required alterations to the metal supporting structures in order to avoid the need to replace sections of the supporting structure. Additional components may be added to the existing metal supporting structure by additional supporting structure, which may also be formed of metals such as steel, and may themselves be subject to corrosion. The additional supporting structure on the metal supporting structure may become increasingly less protected against corrosion over time.

The corrosion protection of a structure comprising multiple inter-connected components is complex and the cathodic protection applied to the pipelines themselves must also be considered. The interplay between the electrical paths that enable the cathodic corrosion protection by way of the anodes connected to the pipelines, the supporting metal structure elements, and the fastener components (which may all be metal members) may be reversible and may change directionality in response to changes in the connectivity between different metal members. Thus, the failure of a corrosion protection source applied to one metal member may affect the corrosion protection of some or all of the other metal members.

For example, if a fastener is in electrical communication with a supporting structure element and the fastener becomes susceptible to corrosion, this may negatively affect the corrosion protection of the supporting structure element. As the fastener and the supporting structure element are in electrical communication, the fastener may draw protection from the supporting structure’s anodic protection sources, thus depleting the protection source for both the fastener and the supporting structure and potentially making the supporting structure more susceptible to corrosion.

Various scenarios may arise in which electrically interconnected metallic members may be negatively impacted by the failure of either dependent or independent corrosion protection sources applied to a single member. In the case of the reduction, or failure, of dedicated corrosion protection applied to a single member, said member may become at least partially reliant on protection by way of another metallic member’s protection sources. As a result, the failure or depletion of a single protection source may affect the corrosion protection of a number of different, electrically interconnected, metallic members.

This problem is particularly relevant for underwater pipelines where extreme and changeable conditions experienced by the underwater pipelines may affect the electrical conductivity within or between metal members and may result in a level of corrosion protection on one or more metal members that falls below an anticipated level or quality.

A reduction in the corrosion protection of either a single metallic member or multiple, electrically interconnected, metallic members may impact the structural strength of the underwater pipeline in various aspects. Thus, it is beneficial to be able to provide additional corrosion protection directly to metallic members of a pipeline or pipeline structure that are identified as lacking in sufficient protection.

By electrically connecting a galvanic anode, or additional galvanic anodes, to a part of the pipeline supporting structure, or a metal member, that has been identified to be at risk of corrosion from poor protection, the lifetime of that part of the structure can be prolonged without requiring that the part be replaced or otherwise maintained.

Moreover, by providing dedicated corrosion protection to an at-risk part of the structure, this part will no longer be reliant on, and therefore no longer consume, the cathodic protection applied to interconnected regions of the overall pipeline structure. Hence, the protection to the otherwise at-risk component of the supporting structure will be restored and said structure will no longer affect the cathodic protection applied to the wider pipeline structure. Thus, the application of the intended cathodic protection to the other parts of the pipeline structure can be restored or maintained.

Existing methods and devices for providing cathodic protection to pipelines require the use of either human divers or work-class remotely-operated vehicles with manipulator arms to affix anodes to component parts of underwater pipeline supporting structures, which have been identified as being susceptible to corrosion due to a lack of sufficient corrosion protection. However, the deployment of either a human diver or a work-class ROV is both time and cost expensive and large work-class ROV vehicles are restricted by their size and manoeuvrability as to the regions accessible to them.

Thus, there is a need for a more flexible and simplified method to allow targeted deployment of an anode to a component part of a pipeline supporting structure that has been identified as requiring additional corrosion protection.

Summary of the Invention

Aspects of the present disclosure are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present disclosure is to provide an apparatus for operatively connecting a galvanic anode to a metal structure for corrosion protection. Another aspect of the present disclosure is to provide a method for operatively connecting a galvanic anode to a metal structure for corrosion protection.

In accordance with an aspect of the present disclosure an apparatus is provided. It may be that the apparatus comprises a first coupling portion for coupling the apparatus to the metal structure and a second coupling portion for coupling the apparatus to the galvanic anode, wherein the first coupling portion comprises a resilient biaser to be actuated by the metal structure to thereby couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least an electrically connecting portion of the metal structure. This may allow the apparatus to be operatively connected to the metal structure without the use of a manipulator arm, in a simplified manner. Said apparatus may also increase the operational flexibility of connecting a galvanic anode to a metal structure, which may allow corrosion protection to be provided to a wider range of metal structures of different geometries and in more locations within a wider pipeline structure, such as to metal structures which may be partially obscured or surrounded by additional pipeline structures.

It may be that the coupling of the first coupling portion of the apparatus to the metal structure electrically connects the second coupling portion of the apparatus to the electrically connecting portion of the metal structure by way of the first coupling portion of the apparatus.

It may be that said electrical and mechanical connections are maintained by the bias of the resilient biaser. This may allow the apparatus to provide continued corrosion protection to the metal structure, based on the properties of the galvanic anode, without the need for external forces to be continually actively applied to the apparatus.

It may be that the mechanical coupling of the apparatus to the metal structure allows a deployment device, such as an unmanned underwater (e.g. remotely operated) vehicle, to deploy the apparatus to the metal structure and to release from the deployed apparatus using a simplified mechanism, without requiring diver or manipulator arm functionality, whilst ensuring that the apparatus remains operatively connected to the metal structure to provide corrosion protection to the metal structure.

It may be that the resilient biaser is configured to couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least part of the metal structure by applying a restoring force.

It may be that the apparatus comprises a trigger mechanism acting on the resilient biaser to prevent the release of potential energy stored by the biaser, and being actuatable to actuate the resilient biaser to apply the restoring force by releasing at least part of the stored potential energy.

It may be that the trigger mechanism is actuatable by contact with at least a trigger contact portion of the metal structure. The contact required to actuate the trigger mechanism may reduce the level of precision required to operatively connect a galvanic anode to a metal structure. This reduction in required precision may allow general-purpose inspection class unmanned underwater vehicles to perform the operative connection without requiring nonstandard functionality. The decrease in the required precision for operatively connecting the galvanic anode to the metal structure may also allow corrosion protection to be applied to a wider range of metal structures, where the comparatively higher degree of precision required by existing techniques was prohibitive.

It may be that the first coupling portion comprises at least first and second arms, the biaser to be actuated to move the first arm with respect to the second arm.

It may be that the first arm is biased towards the second arm by way of the restoring force applied by the resilient biaser.

It may be that the resilient biaser is to couple the first coupling portion to the electrically connecting portion of the metal structure by way of at least one engaging member, at least a portion of which is disposed between the first and second arms, the at least one engaging member being moveable relative to the first and second arms to accommodate the electrically connecting portion of the metal structure.

It may be that the trigger mechanism further comprises a separator engaged to hold the first and second arms open against the bias applied by the biaser in order to receive at least the electrically connecting portion of the metal structure between the first and second arms, the separator being configured, upon contact between the trigger mechanism and a or the trigger contact portion of the metal structure, to disengage to thereby actuate the resilient biaser to move the first arm closer to the second arm to grip the electrically connecting portion of the metal structure between the first and second arms.

It may be that the trigger contact portion and the electrically connecting portion are the same portion of the metal structure, or it may be that they are different portions of the metal structure.

It may be that the separator is configured to disengage upon contact between a portion of the trigger mechanism, such as a portion of the trigger mechanism between the first and second arms of the first coupling portion, and a or the trigger contact portion of the metal structure.

It may be that when the electrically connecting portion of the metal structure is gripped between the first and second arms, the second coupling portion of the apparatus is brought into electrical communication with at least the electrically connecting portion of the metal structure by way of at least one of the arms.

It may be that when the electrically connecting portion of the metal structure is gripped between the first and second arms, the second coupling portion of the apparatus is brought into electrical communication with at least the electrically connecting portion of the metal structure by way of at least one of the arms and the at least one engaging member.

It may be that the at least a portion of the at least one engaging member is disposed between the first and second arms of the first coupling portion extending from a first of the first and second arms in a direction with a component extending towards a second of the first and second arms such that the first coupling portion receives the electrically connecting portion of the metal structure between the engaging member and the second of the first and second arms.

It may be that the at least one engaging member electrically connects the first coupling portion to the electrically contacting portion of the metal structure and the second coupling portion of the apparatus is brought into electrical communication with at least the electrically connecting portion of the metal structure by way of at least the engaging member.

It may be that the second coupling portion of the apparatus is brought into electrical communication with at least the electrically connecting portion of the metal structure by way of at least the engaging member and the at least one of the first and second arms comprising the engaging member or to which the engaging member is coupled.

It may be that the engaging member is pivotable with respect to a receiving bore in a respective arm of the first coupling portion through which the engaging member is inserted in order to accommodate the electrically connecting portion of the metal structure.

It may be that the engaging member of the first coupling portion inhibits decoupling of the apparatus from the metal structure.

It may be that the electrically connecting portion of the metal structure is elongate and that the first coupling portion further comprises a retaining member to inhibit decoupling of the first coupling portion from the metal structure upon actuation of the resilient biaser in a direction perpendicular to a longitudinal axis of the elongate electrically connecting portion of the metal structure.

It may be that the at least one retaining member comprises an overhang which before actuation of the resilient biaser overhangs an opening between the first and second arms for receiving the electrically connecting portion of the metal structure therebetween and which upon actuation of the resilient biaser is engageable with the electrically connecting portion of the metal structure to inhibit decoupling of the first coupling portion therefrom.

It may be that the apparatus is configured to be deployed onto the metal structure in a deployment direction, and that the at least one retaining member is to inhibit decoupling ofthe first coupling portion from the metal structure in a direction opposite to the deployment direction.

It may be that the first coupling portion of the apparatus comprises a lever and a reference surface, the resilient biaser being provided between the lever and the reference surface, the resilient biaser to be actuated to change a distance between the lever and the reference surface to thereby couple the apparatus to the metal structure.

It may be that when the trigger mechanism is actuated, the restoring force applied by the resilient biaser acts to increase the relative distance between the lever and the reference surface, to thereby couple the first coupling portion of the apparatus to the metal structure. The mechanical coupling of the apparatus to the metal structure provided by the first coupling portion comprising a lever and a reference surface may increase the flexibility of deployment of the apparatus to different geometries of metal structure.

It may be that the resilient biaser is to be actuated to mechanically couple the second coupling portion ofthe apparatus to the electrically connecting portion ofthe metal structure.

It may be that mechanically coupling the second portion of the apparatus to the electrically connecting portion of the metal structure electrically connects the second coupling portion ofthe apparatus to the electrically connecting portion ofthe metal structure.

It may be that the resilient biaser is to be actuated to mechanically couple the apparatus to first and second portions of the metal structure, and to provide a more conductive electrical connection between the second coupling portion of the apparatus and the first portion of the metal structure than between the second coupling portion of the apparatus and the second portion of the metal structure.

It may be that the path of electrical communication between the anode and a portion ofthe metal structure may be restricted by an electrically insulating portion ofthe apparatus, for example by an electrically insulating portion of the first or second coupling portions or by an electrically insulating portion coupled to the first or second coupling portions.

It may be that the resilient biaser comprises at least one resiliently deformable member to be deformed by the metal structure to thereby couple the first coupling portion to the metal structure.

It may be that the apparatus is to be received by the metal structure.

It may be that the resilient biaser of the apparatus comprises at least two resiliently deformable members to receive the electrically connecting portion of the metal structure therebetween.

It may be that the resilient biaser is electrically conductive. It may be that one or more of the resiliently deformable members are electrically conductive.

It may be that the resilient biaser (e.g. one or more of the conductive resiliently deformable members) provides at least part of an electrically conductive path between the second coupling portion and the electrically connecting portion of the metal structure.

It may be that the second coupling portion is electrically conductive.

It may be that the first coupling portion is electrically conductive.

It may be that the resiliently deformable members are resiliently deformable by the said electrically connecting portion of the metal structure to actuate the deformable members to apply a restoring force on the said electrically connecting portion of the metal structure to thereby couple the apparatus to the metal structure. The bias applied by the resilient biaser comprising at least two deformable members may allow the apparatus to be operatively connected to the metal structure without requiring that the resilient biaser be pre-loaded to store potential energy.

It may be that at least one resiliently deformable member is engageable with an interfering structure of the electrically connecting portion of the metal structure to maintain coupling of the first coupling portion to said electrically connecting portion of the metal structure.

It may be that the engagement of the at least one resiliently deformable member with the interfering structure of the electrically connecting portion of the metal structure is to interfere with the removal of the apparatus from the metal structure such that the removal of the apparatus from the metal structure is resisted.

It may be that the apparatus is configured to be deployed onto the metal structure in a deployment direction, and wherein the at least one resiliently deformable member is engageable with the interfering structure of the electrically connecting portion of the metal structure to resist removal of the apparatus in a direction opposing the deployment direction of the apparatus relative to the metal structure.

It may be that the electrically connecting portion of the metal structure is elongate and the direction opposing the deployment direction is parallel to the longitudinal axis of the elongate electrically connecting portion of the metal structure.

It may be that to resist removal of the apparatus from the metal structure comprises resisting a slidable motion of the apparatus relative to the metal structure.

It may be that the apparatus is configured to be releasably connectable to an Unmanned Underwater Vehicle, UUV. This may allow the apparatus to be deployed by a (e.g. forward) driving motion of the UUV, which does not require any additional functionality beyond the general-purpose inspection class UUV. The UUV may also be released from the apparatus once the apparatus is mechanically connected to the metal structure by a (e.g. reverse) driving motion of the UUV such that the deployment and release of the apparatus also does not require any functionality beyond the general-purpose inspection class UUV.

It may be that said UUV is a remotely operated vehicle, ROV such as an inspection class ROV.

It may be that the apparatus is configured to be releasably connectable to a corrosion protection inspection equipment channel of said ROV. This may allow the apparatus to be retro-fitted to a general-purpose ROV without requiring modification of the ROV.

In accordance with another aspect of the present disclosure a UUV is provided such as an ROV such as an inspection class ROV. It may be that the UUV is releasably connected to the apparatus provided according to various embodiments.

In accordance with another aspect of the present disclosure a kit of parts for operatively connecting a galvanic anode to a metal structure for corrosion protection is provided. It may be that the kit of parts comprises the apparatus according to one of the above-mentioned aspects and any one or more of: one or more connectors for releasably connecting the apparatus to an Unmanned Underwater Vehicle; a galvanic anode connectable to the second coupling portion of the apparatus.

In accordance with another aspect of the present disclosure a method of operatively connecting a galvanic anode to a metal structure for corrosion protection is provided. It may be that the method comprises actuating a resilient biaser of an apparatus comprising the galvanic anode to thereby couple the apparatus to the metal structure and to electrically connect the galvanic anode to an electrically connecting portion of the metal structure.

It may be that the method comprises a portion of the metal structure actuating the resilient biaser to thereby couple the apparatus to the metal structure and to electrically connect the galvanic anode to an electrically connecting portion of the metal structure.

It may be that the method comprises the resilient biaser applying a restoring force to mechanically couple the apparatus to the metal structure and to electrically connect the galvanic anode to at least part of the metal structure.

It may be that the apparatus has a first coupling portion and a second coupling portion. It may be that the galvanic anode is coupled to the second coupling portion. It may be that the method comprises actuating the resilient biaser to thereby couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least an electrically connecting portion of the metal structure.

It may be that the method comprises a trigger mechanism acting on the resilient biaser to prevent potential energy stored by the resilient biaser from being released.

It may be that the method comprises actuating the resilient biaser to thereby release at least part of the stored potential energy in the biaser to apply a restoring force.

It may be that the method comprises actuating the resilient biaser by actuating the trigger mechanism.

It may be that the method comprises actuating the trigger mechanism by contact between at least the trigger mechanism and a trigger contact portion of the metal structure.

It may be that the method comprises applying a restoring force by the resilient biaser to move a first arm of a first coupling portion with respect to a second arm of the first coupling portion.

It may be that the method comprises coupling the first coupling portion to the electrically connecting portion of the metal structure by the resilient baiser and by way of at least one engaging member, at least a portion of which is disposed between the first and second arms.

It may be that the method comprises moving the at least one engaging member relative to the first and second arms to accommodate the electrically connecting portion of the metal structure.

It may be that the method comprises holding the first and second arms of the first coupling portion open against the bias applied by the resilient biaser.

It may be that the method comprises holding the first and second arms open by a separator of the trigger mechanism.

It may be that the method comprises disengaging the separator by contact between the trigger mechanism and a or the trigger contact portion of the metal structure.

It may be that the method comprises gripping an electrically connecting portion of the metal structure between the first and second arms of the first coupling portion.

It may be that the method comprises bringing the second coupling portion of the apparatus into electrical communication with at least the electrically connecting portion of the metal structure, for example but not necessarily directly or by way of the first coupling portion.

It may be that the method comprises bringing the second coupling portion of the apparatus into electrical communication with at least the electrically connecting portion of the metal structure by way of the first coupling portion and the at least one engaging member.

It may be that the method comprises receiving the electrically connecting portion of the metal structure by the first coupling portion between the engaging member and the second arm, wherein at least a portion of the at least one engaging member is disposed between the first and second arms of the first coupling portion extending from the first arm in a direction with a component extending towards the second arm.

It may be that the method comprises pivoting the engaging member with respect to a receiving bore in a respective arm of the first coupling portion through which the engaging member is inserted in order to accommodate the electrically connecting portion of the metal structure.

It may be that the method comprises inhibiting decoupling of the apparatus from the metal structure by the engaging member of the first coupling portion.

It may be that the method comprises inhibiting decoupling of the first coupling portion from the electrically connecting portion of the metal structure by engaging at least one retaining member with the metal structure following actuation of the resilient biaser.

It may be that the method comprises inhibiting decoupling of the first coupling portion from the electrically connecting portion of the metal structure by an overhang of the at least one retaining member engaging the metal structure following actuation of the resilient biaser.

It may be that the method comprises deploying the apparatus onto the metal structure in a deployment direction and the at least one retaining member resisting removal of the apparatus from the metal structure in a direction opposing the deployment direction, for example during decoupling of a deployment ROV from the apparatus.

It may be that the method comprises changing a distance between a lever and a reference surface of the first coupling portion by the resilient biaser.

It may be that the method comprises applying a restoring force by the resilient biaser to increase a relative distance between the lever and the reference surface.

It may be that the method comprises mechanically coupling a second coupling portion of the apparatus to an electrically connecting portion of the metal structure.

It may be that the method comprises electrically connecting the second coupling portion of the apparatus to the electrically connecting portion of the metal structure.

It may be that the method comprises the metal structure deforming at least one resiliently deformable member of the resilient biaser to thereby couple the first coupling portion to the metal structure.

It may be that the method comprises the metal structure receiving the apparatus.

It may be that the method comprises receiving an electrically connecting portion of the metal structure between at least two resiliently deformable members of the resilient biaser.

It may be that the method comprises resiliently deforming the at least two resiliently deformable members of the resilient biaser, e.g. by way of the electrically connecting portion of the resilient biaser.

It may be that the method comprises the resilient biaser (e.g. one or more of the conductive resiliently deformable members) providing at least part of an electrically conductive path between the second coupling portion and the electrically connecting portion of the metal structure.

It may be that the method comprises applying a restoring force to the electrically connecting portion of the metal structure by the resiliently deformed members.

It may be that the method comprises engaging at least one resiliently deformable member with an interfering structure of the electrically connecting portion of the metal structure to maintain coupling of the first coupling portion to said electrically connecting portion of the metal structure.

It may be that the method comprises interfering by the interfering structure of the electrically connecting portion of the metal structure with the removal of the apparatus from the metal structure such that the removal of the apparatus from the metal structure is resisted.

It may be that the method comprises deploying the apparatus onto the metal structure in a deployment direction, and engaging the at least one resiliently deformable member with the interfering structure of the electrically connecting portion of the metal structure to resist removal of the apparatus in a direction opposing the deployment direction of the apparatus relative to the metal structure, for example during decoupling of a deployment ROV from the apparatus.

It may be that the method comprises resisting removal of the apparatus from the metal structure comprises by resisting a slidable motion of the apparatus relative to the metal structure.

It may be that the method comprises actuating the resilient biaser by a remotely operated vehicle bringing the apparatus into contact with the metal structure.

It may be that the apparatus is releasably coupled to the remotely operated vehicle prior to the apparatus being brought into contact with the metal structure.

It may be that the method comprises decoupling the apparatus from the remotely operated vehicle after the resilient biaser has been actuated.

In accordance with another aspect of the present disclosure a method of releasably connecting an apparatus to a UUV is provided, wherein the apparatus is for operatively connecting a galvanic anode to a metal structure.

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

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are further described hereinafter with reference to the accompanying drawings, in which:

[0001] Figures 1a-1e schematically illustrate cross-sectional views of a first embodiment of an apparatus for operatively connecting a galvanic anode to a metal structure;

[0002] Figure 1f illustrates an exemplary configuration of engaging members of the apparatus;

[0003] Figures 2a-2c schematically illustrate cross-sectional views of a second embodiment of the apparatus for operatively connecting a galvanic anode to the metal structure;

[0004] Figures 3a-3f schematically illustrate cross-sectional views of a third embodiment of the apparatus for operatively connecting a galvanic anode to the metal structure;

[0005] Figures 4a and 4b schematically illustrate cross-sectional views of an unmanned underwater vehicle releasably connected to an embodiment of the apparatus for operatively connecting the galvanic anode to the metal structure;

[0006] Figures 4c and 4d illustrate an exemplary releasable connector for deploying an apparatus by an ROV;

[0007] Figure 5 schematically illustrates a flow chart illustrating the method performed to operatively connect a galvanic anode to the metal structure;

[0008] Figure 6 schematically illustrates a flow chart illustrating the method performed to operatively connect the galvanic anode to the metal structure by way of the embodiment of the apparatus illustrated in Figures 1a-1e;

[0009] Figure 7 schematically illustrates a flow chart illustrating the method performed to operatively connect the galvanic anode to the metal structure by way of the embodiment of the apparatus illustrated in Figures 2a-2c; and [0010] Figure 8 schematically illustrates a flow chart illustrating the method performed to operatively connect the galvanic anode to the metal structure by way of the embodiment of the apparatus illustrated in Figures 3a-3f.

DETAILED DESCRIPTION [0011] The present invention relates to an apparatus and a method for operatively connecting a galvanic anode to a metal structure to provide corrosion protection to the metal structure, which may be part of a support for an underwater pipeline. The apparatus may comprise a first coupling portion for coupling the apparatus to the metal structure and a second coupling portion for coupling the apparatus to the galvanic anode, where the first coupling portion may comprise a resilient biaser to be actuated by the metal structure to thereby couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least portion of the metal structure. This apparatus may increase the flexibility in operationally connecting a galvanic anode to an underwater metal structure of a pipeline that requires additional or retro-fitted corrosion protection. This apparatus and method may allow corrosion protection to be provided to a wider range of metal structures of different geometries and in more locations within a wider pipeline structure. The apparatus may also allow a galvanic anode to be operatively coupled to a metal structure by the use of a general-purpose inspection class unmanned underwater vehicle (UUV), as it may allow for a simplified method of deployment which does not require the use of advanced functionality associated with a work class UUV, such as a manipulator arm coupled to UUV, or intervention from a human diver.

[0012] Figure 1a shows apparatus 100 for operatively connecting a galvanic anode 108 to a metal structure 120, see Figure 1d. As shown in Figure 1 d, the metal structure 120 may comprise a plurality of planar metallic surfaces, 121, provided around a central metallic rod, 122. The metal structure 120 may be a portion of a supporting structure for an underwater pipeline or may be a structure to attach the supporting structure to the pipeline or to a retro-fitted pipeline. The metal structure may be made of steel.

[0013] Referring back to Figure 1a, the apparatus 100 may comprise a first coupling portion 101 for coupling the apparatus to the metal structure 120 and a second coupling portion 107 for coupling the apparatus to the galvanic anode 108. The first coupling portion 101 may be electrically conductive. The second coupling portion 107 may be electrically conductive. The galvanic anode 108 may comprise a sacrificial metal, such as zinc, which when operatively connected to the metal structure 120 may be preferentially corroded in favour of the metal structure in order to protect the metal of the metal structure 120.

[0014] The first coupling portion 101 may comprise a clamp comprising first 103 and second 104 arms and a resilient biaser 102 provided between the first 103 and second 104 arms. As shown in Figure 1a, the clamping ends of the first 103 and second 104 arms may be biased towards each other by the resilient biaser 102. Alternatively, it may be that the clamping end of only one of the arms 103, 104 is biased towards the clamping end of the other by the resilient biaser 102. The resilient biaser 102 may be a spring, such as but not limited to a compression helical spring or a coil spring.

[0015] As shown in Figure 1a, the galvanic anode 108 may be coupled to the apparatus 100 by second coupling portion 107, where the second coupling portion 107 may be a region of the first arm 103 of the first coupling portion. Alternatively, the second coupling portion 107 may be a region of the second arm 104 of the first coupling portion. Alternatively, the second coupling portion may be provided by an additional electrically conductive structural element such as a metallic block or metallic plate coupled to the first or second arms 103, 104. The second coupling portion 107 may alternatively be an extension of the first or second arms.

[0016] As shown in Figure 1a, the apparatus 100 may have a relaxed state in which clamping ends of the first and second arms 103, 104 may be in close proximity to each other, or in engagement with each other, under the bias provided by the resilient biaser 102. As shown in Figure 1b, a force may be exerted against the bias of the resilient biaser to provide the apparatus with a loaded state in which the clamping ends of the first and second arms 103, 104 are separated from each other. This is shown in Figure 1b where the resilient biaser, 102, may be compressed by way of an external force applied to the non-clamping ends of the first 103 and second 104 arms of the first coupling portion to thereby increase the separation between the clamping ends of the first and second arms (Di becomes Di’ when the non-clamping ends of the arms 103, 104 are acted upon by the external force Di’ being greater than Di) and to decrease the separation between the non-clamping ends of the arms (D2 becomes D2’ when the non-clamping ends of the arms 103, 104 are acted upon by the external force, D2’ being less than D2).

[0017] Potential energy may be stored in the resilient biaser 102 during this change from the relaxed state to the loaded state, i.e. during compression of the resilient biaser

102. As the biaser 102 is resilient to this loading by compression, the biaser 102 will exert an elastic restoring force to counteract the compression in order to return the apparatus to the relaxed state shown in Figure 1a where the clamping ends of the first 103 and second 104 arms are biased together. By exerting this restoring force, the resilient biaser 102 may move the clamping ends of the first and second arms

103, 104 towards each other. Alternatively, the biaser 102 may only move the clamping end of the first arm 103 relative to the clamping end of the second arm 104, or vice versa.

[0018] As shown in Figure 1c, the apparatus 100 may further comprise a decouplable trigger mechanism 109 that may be fitted between the first 103 and second 104 arms after the resilient biaser 102 is loaded, e.g. by compression. The trigger mechanism 109 may be engaged to prevent the release of at least part of the potential energy that is stored by the resilient biaser 102 during the compression of the resilient biaser 102. The trigger mechanism 109 may prevent the release of at least some of the stored potential energy in the resilient biaser 102 by acting on the first and second arms 103, 104 of the first coupling portion to limit the relative movement of the arms 103, 104 under the restoring force of the biaser 102. As shown in Figure 1c, the trigger mechanism 109 may comprise a separator 110 to inhibit relative movement of the first and second arms 103, 104 under the bias of the biaser 102, which holds the first and second arms 103, 104 open against the bias applied by the biaser 102. The separator 110 may be installed to the apparatus 100 when the clamping ends of the first and second arms 103, 104 have been separated. The separator may comprise a U-shaped bracket to be fitted around the non-clamping ends of the first and second arms 103, 104. The bracket holds the clamping ends of the first and second arms 103, 104 apart, in their separated position, by preventing the non-clamping ends of the first and second arms 103, 104 from moving away from each other under the bias of the resilient biaser 102.

[0019] Figure 1 d shows that the clamping ends of the first 103 and second 104 arms of the first coupling portion 101 can be held open against the bias applied by the resilient biaser 102 by the separator 110, in order to receive the rod, 122, of the metal structure 120 between the clamping ends of the first and second arms 103, 104.

[0020] The trigger mechanism 109 may further comprise a trigger 111.

[0021] The trigger mechanism 109 may be actuatable by contact between the trigger 111 thereof and at least a trigger contact portion of the metal structure 120, which as illustrated by Figure 1d may be the rod, 122, of the metal structure 120. Alternatively, the trigger contact portion of the metal structure 120 may be any other portion of the metal structure 120, including but not limited to, one of the surfaces 121 of the metal structure.

[0022] Upon contact between the trigger 111 of the trigger mechanism 109 and the trigger contact portion of the metal structure 120, the trigger mechanism may be disengaged from the arms 103, 104 to thereby actuate the resilient biaser 102.

[0023] The actuation of the resilient biaser 102 may release at least some of the potential energy stored in the biaser to move the clamping end of the first arm 103 closer to the clamping end of the second arm 104 to thereby grip the trigger contact portion (in this case the rod 122), which in this case is also an electrically connecting portion, of the metal structure 120 between the first and second arms 103, 104. The gripping of the rod 122 of the metal structure between the first and second arms 103, 104 of the first coupling portion is shown in Figure 1e.

[0024] The disengagement of the trigger mechanism 109 may cause the separator 110 to be removed from contact with the non-clamping ends of the first 103 and second 104 arms of the first coupling portion. The release of the separator 110 may thus cause the resilient biaser 102 to be actuated to exert a restoring force on the first and second arms 103, 104 that may result in the separation between the clamping ends of the arms 103, 104 decreasing from DT to Di, while the separation between nonclamping ends of the arms may be increased from D2’ to D2.

[0025] The restoring force exerted by the resilient biaser 102 on the first and second arms 103, 104 may maintain the clamp’s grip on the rod 122.

[0026] As shown in Figure 1e, the gripping of the rod 122 between the first 103 and second 104 arms of the first coupling portion 101 provides mechanical coupling between the first coupling portion 101 and the metal structure 120.

[0027] The gripping of the rod 122 of the metal structure may be performed by the resilient biaser 102 via direct contact of the first 103 and second 104 arms of the first coupling portion 101 with the rod 122. Alternatively, the first coupling portion 101 may further comprise at least one engaging member. The gripping of the rod 122 may be performed by the resilient biaser 102 via at least one engaging member, where the actuation of the resilient biaser provides contact between the rod 122, the at least one engaging member and either the first 103 or second arm 104, or provides contact between the rod 122, and at least two engaging members with at least one engaging member disposed on each of the first 103 and second 104 arms. At least a portion of the at least one engaging member may be disposed between the first 103 and second 104 arms and the at least one engaging member may be moveable relative to the first and second arms to accommodate the electrically connecting portion of the metal structure [0028] As shown in Figure 1 f, the at least one engaging member 123, 124 may be coupled to or disposed through the first 103 or second 104 arm of the first coupling portion

101. Two or more engaging members 123, 124 may be coupled to or disposed through either or each of the first 103 and second 104 arms. The position of the engaging members 123, 124 coupled to or disposed through either or each of the first or second arms may be offset along the length of the respective arms to account for electrically connecting portions ofthe metal structure, e.g. rods, having different shapes and sizes or having variable sizes e.g. due to corrosion. The engaging members 123, 124 may be the same or different lengths. The lengths and relative positions of at least two engaging members 123, 124 may be configured to ensure electrical connection of the first coupling portion 101 to the rod 122 of the metal structure by way of an interaction between the rod 122 and at least one ofthe at least two engaging members. The at least one engaging member 123, 124 may inhibit decoupling of the apparatus from the metal structure. The electrically connecting portion ofthe metal structure, e.g. the rod 122, may be elongate and the positioning the engaging member(s) along a respective arm of the first coupling portion may inhibit removal of the apparatus in a direction perpendicular to the longitudinal axis of the elongate electrically connecting portion of the metal structure. The at least one engaging member 123, 124 may additionally or alternatively inhibit removal of the apparatus in a direction parallel to the longitudinal axis of the elongate rod by way of the restoring force applied to the rod by the resilient biaser.

[0029] The engaging member(s) 123, 124 may be teeth, the engaging portion 123a, 124a of the engaging member(s) 123, 124 may be flat-ended, pointed or serrated to provide improved electrical connection with the rod 122 of the metal structure. The engaging member(s) may protrude substantially perpendicularly to the respective arm(s) of the first coupling portion 101 or at different angles with respect to the arm(s) of the first coupling portion 101. Three or more engaging members may be arranged in a single or in multiple rows on either the first 103 or second 104 arms.

[0030] The engaging member(s) may be integrally formed with the first 103 or second 104 arms of the first coupling portion 101, or may be coupled to the first 103 or second 104 arms. The engaging member(s) 123, 124 may be coupled to the first 103 or second 104 arms to allow the engaging member(s) to be moveable, e.g. pivotable with respect to the respective arm, when contacted by the rod 122 of the metal structure. The movement ofthe engaging member(s) 123, 124 may accommodate for different shapes and sizes of the rod of the metal structure and may ensure electrical connection between the engaging member(s) and the rod 122. The movement of the engaging member(s) may be preferentially in the direction of the insertion of the rod 122 between the arms of the first coupling portion 101. The pivotable range of movement of the engaging member(s) may be limited so that the engaging member applies an opposing force against the rod 122 of the metal structure in order to provide improved electrical connection between the rod 122 of the metal structure and the first coupling portion 101. The engaging members may be screws inserted through respective receiving bores in at least the first 103 or second 104 arm of the first coupling portion 101.

[0031] The engaging member(s) may be pivotable with respect to the receiving bore(s) in either the first 103 or second 104 arm of the first coupling portion 101. The pivotal motion of the engaging members with respect to the bore(s) may be to accommodate the rod 122 of the metal structure. The pivotal motion of the engaging members with respect to the bore(s) may be enabled by a limited surface area contact of the engaging member(s), e.g. screw(s), with the internal walls of the bore(s). The limited surface area contact may be provided by thread(s) of the screw(s) with the internal walls of the bore(s). The limited surface area contact may be provided by the region of either the first 103 or second 104 arm through which the receiving bore extends having a limited thickness. The thickness of the region of the arm through which the bore extends may be substantially smaller than the length of the engaging member, e.g. the screw. For example, the engaging member may be two or three times longer than the depth of the receiving bore.

[0032] Alternatively, or additionally, the screw may have a core diameter less than the diameter of the receiving bore e.g., it may be that there is a gap between the core of the screw and the inner wall of the bore. The core diameter of the screw may be the diameter of the body of the screw excluding the thread and the point or tapered region of the screw.

[0033] The pivotal motion of the engaging member with respect to the bore may also be enabled by the malleability of the engaging member material, the arm (103,104) material or both the engaging member and arm material.

[0034] The screw may be a self-tapping screw. A self-tapping screw may provide increased electrical connectivity between the rod 122 of the metal structure and the either first 103 or second 104 arm of the first coupling portion 101. The self-tapping screw may also provide increased mechanical coupling between the rod 122 of the metal structure and the first 103 or second 104 arm of the first coupling region 101 as the self-tapping screw may resist removal from the respective arm of the first coupling portion 101 through which it is inserted. The self-tapping screw may have at least one washer disposed thereon at respective lengths of the screw on either side of the receiving bore. The washers may be to resist removal of the self-tapping screw from the bore through which the self-tapping screw is inserted.

[0035] Alternatively, the engaging member may be a non self-tapping screw or a bolt. The non self-tapping screw or bolt may have at least one nut and/or one washer disposed thereon at a respective length of the screw or bolt extending beyond the receiving bore. For example, at least two nuts or washers may be disposed on the bolt or screw on either side of the receiving bore to prevent the screw or bolt from being removed from the respective arm (103,104) of the first coupling portion 101 through which the screw or bolt is inserted. Alternatively, the engaging member may be a rod with at least two stoppers, each stopper similarly disposed at the respective lengths of the rod extending on either side of the receiving bore.

[0036] The pivotal motion of the engaging member with respect to the receiving bore may be provided by a substantially circular bore having a radius larger than the outside radius of the engaging member, but smaller than an outside radius of a stopper or nut and/or washer disposed on the respective lengths of the engaging member on either side of the receiving bore. Alternatively, the pivotal motion of the engaging member with respect to the receiving bore may be provided by an elongate bore, the bore may be elongate in a direction perpendicular to the direction in which the bore extends through the arm, i.e. the bore may be elongate in a direction perpendicular to the direction in which engaging member is inserted into the arm. The elongate bore may have one axis substantially equal to the outside radius of the engaging member, and one axis substantially larger than the outside radius of the engaging member. A retaining member 125, as shown in Figure 1f, may be fixed to or integrally formed with the clamping end 103a, 104a of the first 103 or second 104 arm. The retaining member 125 may provide an overhang to retain the rod 122 of the metal structure between the first 103 and second 104 arms upon actuation of the resilient biaser. The retaining member may be fixed to or integrally formed with the clamping end of the first 103 or second 104 arm to prevent removal of the apparatus from the rod 122 of the metal structure after actuation of the resilient biaser, for example during release of the apparatus from the deployment ROV.

[0037] The retaining member 125 may be shaped to oppose a force applied to the first coupling portion 101 in a direction which may result in the removal of the apparatus from the rod 122 of the metal structure. For example, the apparatus may be deployed onto the metal structure in a deployment direction and the retaining member may resist removal of the apparatus from the metal structure in a direction opposing the deployment direction, for example following deployment of the apparatus onto the metal structure and during decoupling of the ROV from the apparatus.

[0038] The retaining member 125 may, for example, be straight, curved or with a shaped end-section to enclose the rod 122 of the metal structure between the overhang and the first and second arms once the resilient biaser has been actuated. The retaining member 125 may comprise an overhang which before actuation (Figure 1c) of the resilient biaser 102 overhangs an opening between the first 103 and second 104 arms for receiving the electrically connecting portion 122 of the metal structure therebetween and which upon actuation (Figure 1a) of the resilient biaser 102 is engageable with the electrically connecting portion 122 of the metal structure to inhibit decoupling of the first coupling portion 101 from the metal structure. The retaining member 125 may have an end portion shaped to fit into a locking mechanism subsequent to the actuation of the resilient biaser, for example the locking mechanism may be a groove on the opposing arm of the first coupling portion 101. The locking mechanism may further oppose the removal of the apparatus from the rod 122 of the metal structure during release of the apparatus from the deployment ROV, or during the application of any other forces, for example forces exerted by fluid flows, acting in the removal direction of the apparatus with respect to the rod 122 of the metal structure.

[0039] As mentioned above, the first 101 and second 107 coupling portions of the apparatus 100 may be electrically conductive. There also may be an electrically conductive path between the first and second coupling portions 101, 107 of the apparatus 100, for example through the first arm, 103. Thus, the mechanical coupling between the first coupling portion 101 and the rod 122 of the metal structure 120 may provide electrical communication between the galvanic anode 108 and the metal structure 120 by way of the first and second coupling portions 101, 107, such that the mechanical coupling of the first coupling portion 101 of the apparatus to the rod 122 electrically connects the second coupling portion 107 of the apparatus 100 to the rod 122 by way of the first coupling portion 101 of the apparatus 100.

[0040] The electrical connection between the second coupling portion 107 and the rod 122 provides electrical communication between the galvanic anode 108 and at least a portion of the metal structure 120, which provides corrosion protection to the at least a portion of the metal structure 120. The apparatus 100 may be deployed and installed on the metal structure without the need for a manipulator arm or human diver because the trigger mechanism of apparatus 100 allows the resilient biaser to be actuated by simplified means of contact between the metal structure 120 (in the above example, the rod 122) and the trigger 111 of the trigger mechanism 109 of the apparatus 100. Thus, deployment devices with advanced functionality to provide higher degrees of freedom during deployment, with respect to general-purpose inspection class UUVs, are not required to install the apparatus 100 to the metal structure 120. This helps to keep the cost of deploying the anode 108 down.

[0041] Figure 2a shows another apparatus 200 for operatively connecting a galvanic anode 208 to a metal structure 120. As before, the metal structure 120 may comprise a plurality of surfaces, 121, provided around a central rod, 122. Alternatively, the metal structure 120 may be any metal structure including, but not limited to, a metal structure comprising two opposing surfaces. The apparatus 200 may be installed on the metal structure 120 to provide galvanic protection to at least a portion of the metal structure 120.

[0042] The apparatus 200 may comprise a first coupling portion 201 for coupling the apparatus to the metal structure 120 and a second coupling portion 207 for coupling the apparatus 200 to the galvanic anode 208, as shown in Figure 2a.

[0043] The first coupling portion 201 is illustrated in more detail in Figure 2b. The first coupling portion 201 may comprise a lever 203 coupled to a reference surface 204. As shown in Figure 2b, the reference surface 204 of the first coupling portion 201 may be coupled to the second coupling portion 207 which in this case is a continuation of a surface providing the reference surface 204. The reference surface 204 of the first coupling portion 201 may thus be laterally offset (in the x direction of Figure 2a) from, and integrally formed with, the second coupling portion 207. Alternatively, the second coupling portion 207 may be a separate conductive structural element such as a conductive block or conductive plate coupled to the reference surface 204.

[0044] A resilient biaser 202 may be provided between the lever 203 and the reference surface 204.

[0045] The apparatus 200 may be provided with a relaxed state in which the biaser 202 is relaxed. In this case, as shown in Figure 2b, the lever 203 is in a first position relative to the reference surface such that a minimum separation between the lever 203 and the reference surface 204 of the first coupling portion is Di’.

[0046] The resilient biaser 202 may be compressed to store potential energy by applying an external force to the resilient biaser 202 in a direction opposing the bias of the biaser 202, for example by exerting a force on the lever 203 towards the reference surface 204 such that the biaser 202, which may for example be a coil spring, is compressed between the lever 203 and the reference surface 204. This may cause the lever 203 to be rotated about a pivot from the first position to a second position relative to the reference surface 204 in which the minimum separation between the lever 203 and the reference surface 204 of the first coupling portion is reduced from D? to Di. This provides the apparatus 200 with a loaded state.

[0047] As shown in Figure 2a, the apparatus 200 may be held in its loaded state by a trigger mechanism. The trigger mechanism illustrated in Figure 2a comprises a fastener 212, such as a screw, and a decouplable trigger 213 to hold the lever 203 in its second position relative to the reference surface 204. The lever 203 has a hole 206 extending therethrough at an intermediate position along its length through which the fastener 212 extends. A torque may be applied to the screw 212 to hold the resilient biaser in the compressed state. Indeed, a torque may be applied to the screw to both simultaneously compress the resilient biaser and hold the resilient biaser in the compressed state. The screw 212 may be received by the reference surface 204, which may or may not be pre-threaded to receive the screw 212. The screw 212 may have a head which is sized and positioned to pass through the hole 206 in the lever 203, but the trigger 213, which in the example of Figure 2a may be L-shaped, may be inserted between the head of the screw 212 and the hole 206 such that the head of the screw 212 overhangs a portion of the trigger 213 to thereby prevent the hole 206 from sliding over the head of the screw 212. The application of a torque to the screw 212 to hold the resilient biaser in its compressed state may cause the head of the screw 212 to hold the trigger 213 between the head of the screw 212 and the lever 203. Thus, the trigger 213 and the screw 212 may hold the apparatus in its loaded state.

[0048] As the resilient biaser 202 is resilient to the change from the relaxed state to the loaded state resulting from the external force acting to oppose the bias of the resilient biaser, the resilient biaser will store potential energy during the change in state or compression. This stored potential energy may be exerted as a restoring force by the resilient biaser.

[0049] The trigger mechanism may prevent the release of the potential energy stored by the biaser 202. The trigger mechanism may be actuatable to actuate the resilient biaser to apply the restoring force between the lever 203 and reference surface 204 by releasing at least part of the potential energy stored by the resilient biaser 202.

[0050] The trigger mechanism may be actuated by contact between the trigger 213 and at least a trigger contact portion of the metal structure as the apparatus 200 is received by the metal structure 120. As shown in Figure 2c, the trigger contact portion of the metal structure may be the rod, 122. Alternatively, the trigger contact portion may be any other suitable portion of the metal structure.

[0051] The resilient biaser 202 may be provided such that the actuation of the resilient biaser 202 may cause it to expand to thereby cause a change in a distance between the lever 203 and the reference surface 204. As shown in Figure 2a, expansion of the resilient biaser 202 may increase a minimum separation between the lever 203 and the reference surface 204 from Di in its loaded state to D? in its relaxed state by moving the lever 203 relative to the reference surface 204.

[0052] As shown in Figure 2c, when the apparatus 200 is received by the metal structure 120, the underside of the reference surface 204 may engage a surface 121 of the metal structure 120, and the trigger 213 may come into contact with the trigger contact portion (which may be the rod 122) of the metal structure 120. Upon contact between the trigger 213 and the trigger contact portion (e.g. rod 122) of the metal structure 120 the trigger mechanism may be actuated by the disengagement of the trigger 213 between the lever 203 and the screw 212. As a result of the disengagement of the trigger 213, the resilient biaser 202 may be released from its compressed state as the screw, including screw head, may pass through the hole 206 in the lever 203. Thus, the resilient biaser 202, which may engage an area on the lever 203 larger than the area of the hole 206 in the lever such that the biaser 202 does not pass through the hole 206, may be actuated to exert a restoring force between the lever 203 and the reference surface 204, to thereby increase a relative distance between the lever 203 and the reference surface 204. Thus, Di in Figure 2a becomes D₂in Figure 2c.

[0053] As the trigger mechanism is actuated to cause the resilient biaser 202 to increase a relative distance between the lever 203 and the reference surface 204, mechanical contact between the lever 203 of the first coupling portion 201 and the rod 122 of the metal structure 120, and mechanical contact between the reference surface 204 of the first coupling portion and the opposing surface 121 of the metal structure 120 is provided.

[0054] The apparatus 200 may thus be held within the metal structure 120 between the rod 122 and the surface 121 by the restoring force of the resilient biaser 202 acting on the lever 203 and the reference surface 204 of the first coupling portion 201.

[0055] The mechanical coupling of the first coupling portion 201 of the apparatus 200 with the metal structure 120 may provide mechanical coupling of the second coupling portion 207 of the apparatus 200 with the internal surface 121 of the metal structure 120, as shown in Figure 2c.

[0056] It may be that the reference surface 204 is provided by a conductive (e.g. metallic) plate. In this case, as illustrated in Figure 2c, the mechanical coupling of the second coupling portion 207 of the apparatus 200 with an internal surface 121 of the metal structure 120 may provide electrical communication between the metal structure 120 and the anode 208 by way of the second coupling portion 207. Additionally, or alternatively, it may be that the first coupling portion 201 of apparatus 200 is electrically conductive and that there is a conductive path between the first and second coupling portions 201,207, such that electrical communication between the anode 208 and the metal structure 120 may be provided by way of the first coupling portion 201 through the second coupling portion 207.

[0057] It may be that the second coupling portion 207 is provided on an underside of the reference surface 204 of the first coupling portion, in which case it may be that the resilient biaser provides a direct mechanical connection between the anode and the metal structure. If a mechanical connection is provided directly between the anode and the metal structure then electrical communication may be established directly between the anode and the metal structure.

[0058] In another example, the path of electrical communication between the anode and a portion of the metal structure 120 may be restricted by an electrically insulating portion of the first and second coupling portions or by an electrically insulating element such as a plate or block provided between the metal structure and the first or second coupling portions. In some embodiments, the anode 208 is prevented from electrically connecting to the surface 121 of the metal structure 120 by an insulating block or plate on which the anode 208 is provided (e.g. between the anode 208 and the reference surface 204). This prevents corrosion protection from being consumed by the metal structure 120 through the insulating portion, block or plate, thereby directing it to a desired portion of the metal structure 120.

[0059] The electrical conductivity of the first and second coupling portions may be determined by the materials of the first and the second coupling portions. Thus, the path of electrical communication between the anode 208 and the metal structure 120 may be determined by the conductivity of the first and second coupling portions and said path of electrical communication may be governed by the materials of the first and second coupling portions.

[0060] The electrical connection between the galvanic anode 208 and the metal structure 120 may provide corrosion protection to at least a portion of the metal structure 120. The trigger mechanism of apparatus 200 may allow the apparatus 200 to be deployed to the metal structure 120 without the need fora manipulator arm or human diver as the trigger mechanism of apparatus 200 allows the resilient biaser 202 to be actuated by simplified means of contact between the metal structure and the trigger mechanism of the apparatus.

[0061] Figure 3a shows another apparatus 300 for operatively connecting a galvanic anode 308 to a metal structure 120. The metal structure 120 may comprise a plurality of surfaces 121 provided around a central rod 122.

[0062] The apparatus 300 may comprise a first coupling portion 301 for coupling the apparatus to the metal structure 120 and a second coupling portion 307 for coupling the apparatus to the galvanic anode 308.

[0063] The first coupling portion 301 may comprise a metallic or otherwise conductive plate with an opening to receive a portion of the metal structure 120, such as the rod 122, as illustrated in Figure 3a. The first coupling portion 301 may further comprise a resilient biaser 302, shown in more detail in Figure 3c. The resilient biaser may comprise at least two resiliently deformable members 303, 304, at least one of which is metallic or otherwise electrically conductive, which may be coupled to each other by the plate. As shown in Figure 3a, the resiliently deformable members may be provided opposite each other, at either side of the opening of the first coupling portion. Alternatively, the resilient biaser may comprise more than two deformable members. The at least two deformable members may be equally spaced around the opening or preferentially grouped around one side of the opening.

[0064] As shown in Figure 3c, the resilient biaser 302 may comprise the at least two resiliently deformable members 303, 304 coupled to each other via a coupling component 305 of the resilient biaser 302 which may be at least a region of the plate of the first coupling portion 301.

[0065] Alternatively, the galvanic anode 308 may be a ring anode 408, as shown in Figure 4c, having an annulus with an internal opening 409. The resiliently deformable members 303, 304 may be coupled to the ring anode such that the resiliently deformable members extend from the annulus of the ring galvanic anode towards the centre of the internal opening provided by the annulus of the ring galvanic anode such that first ends of the resiliently deformable members engage with the rod 122 of the metal structure to form the first coupling portion 301 of the apparatus. Second ends of the resiliently deformable members 303, 304 may be coupled to the galvanic anode 308 to form the second coupling portion 307 of the apparatus. The at least two resiliently deformable members may be provided on opposite sides of the internal opening. The resilient biaser may comprise at least three resiliently deformable members equally spaced around the opening or preferentially grouped around one side of the internal opening. The resilient biaser may comprise a plurality of resiliently deformable members arranged in a concentric configuration around the opening, for example the plurality of resiliently deformable members may be provided in a petal configuration.

[0066] One or more of the at least two resiliently deformable members 303, 304 and said at least a region of the plate of the first coupling portion may be electrically conductive.

[0067] One or more of the at least two resiliently deformable members e.g. 303, 304 may have a flat, pointed or otherwise shaped contacting portion to provide the mechanical coupling and electrical connection with the rod 122 of the metal structure. The contacting portion of the at least two resiliently deformable members 303, 304 may be shaped to engage with an interference structure of the rod 122 of the metal structure to maintain coupling of the first coupling portion 101 to the rod 122 of the metal structure. For example, the at least two resiliently deformable members 303, 304 may be engageable with an interference structure of the rod 122 of the metal structure that interferes with the removal of the apparatus from the metal structure so as to resist removal of the apparatus from the metal structure e.g. the at least two resiliently deformable members 303, 304 engaged with the interfering structure of the rod may resist the removal of the apparatus from the metal structure by resisting a slidable motion of the apparatus relative to the metal structure. The interfering structure of the electrically connecting portion of the metal structure may be e.g. grooves in or on a surface of the metal structure or a thread thereof. The apparatus may be configured to be deployed onto the metal structure in a deployment direction, such as that shown by the bold directional arrows between Figures 3a and 3e. The at least two resiliently deformable members 303, 304 may be engageable with the interfering structure of the rod 122 of the metal structure to resist removal of the apparatus in a direction opposing the deployment direction of the apparatus relative to the metal structure. For example, the rod 122 may be elongate and the deployment direction, as shown in Figure 3a and 3e, may be parallel to the longitudinal axis of the elongate rod 122. The resistance to removal provided by the at least resiliently deformable members engaged with the interfering structure of the rod may be sufficient to prevent accidental or unintended removal of the apparatus from the rod 122 of the metal structure, for example following deployment of the apparatus onto the metal structure and during decoupling of a deployment ROV from the apparatus. The shaping of the contacting portions of the resiliently deformable members may be configured with respect to the interfering structure of the rod of the metal structure to allow removal of the apparatus from the rod 122 when sufficient force is applied to the apparatus. The resiliently deformable members may be configured to facilitate removal of the apparatus from the rod 122 upon the application of a torque to the apparatus. For example, the apparatus may be rotated off the rod 122.

[0068] The resilient deformable members may be configured to preferentially enable deployment of the apparatus onto the metal structure as compared to removal of the apparatus from the metal structure. For example, the resiliently deformable members may be shaped such that the actuation of the resilient biaser upon receiving the rod of the metal structure between the resiliently deformable members push the resiliently deformable members apart, allowing relatively easy deployment. The shaping of the resiliently deformable members may also push the resiliently deformable members together, for example upon inadvertent attempted removal of the apparatus from the metal structure (i.e. in a direction opposing the deployment direction), for example during decoupling of the apparatus from a deployment ROV, such that the removal of the apparatus from the metal structure is resisted. The at least two resiliently deformable members 303, 304 of the resilient biaser may be shaped as illustrated in Figures 3a,c,d,f, or may be otherwise shaped e.g. the resiliently deformable members may be planar. In another example, the at least two resiliently deformable members may comprise a first length extending away from the internal opening provided by the annulus of the ring galvanic anode. The resiliently deformable members may be further shaped to bend back towards the internal opening of the ring anode and may comprise a second length extending towards the centre of the internal opening and overhanging the internal opening of the annulus of the ring anode in order to engage the electrically connecting portion of the metal structure. A first end of a resiliently deformable member may be directly coupled to the galvanic anode, for example for the ring anode, or may be coupled to a plate of the first coupling portion by way of fasteners, and a second end of the deformable member, may provide contact with the rod of the metal structure. The resiliently deformable members 303, 304 may be actuated by the rod 122 of the metal structure 120, when it is received by the opening of the plate, to both mechanically and electrically couple the first coupling portion 301 of the apparatus 300 to the metal structure 120.

[0069] As shown in Figure 3b, which shows the underside of the plate of Figure 3a, the galvanic anode 308 may be coupled to the apparatus 300 by a second coupling portion 307, where the second coupling portion 307 may be an underside of the plate comprising the first coupling portion 301. Alternatively, the second coupling portion 307 may be provided on the same surface of the plate as the first coupling portion, in a different region of the surface to the first coupling portion.

[0070] The first and second coupling portions, 301, 307, of apparatus 300 described above may thus be disposed on the same surface, or different surfaces of the apparatus 300.

[0071] The at least two resiliently deformable members may both be connected to at least a region of the plate of the first coupling portion by way of fasteners 306, which may or may not be electrically conductive. Alternatively, the at least two resiliently deformable members may be integrally formed with the plate.

[0072] Electrical communication is provided between the at least two deformable conductive members 303, 304 and the conductive plate of the first coupling portion 301 of the apparatus 300 either by direct contact between each of the deformable members 303, 304 and the region of the plate of the first coupling portion 301, by way of the fasteners 306, or any combination thereof.

[0073] Electrical communication is provided between the first coupling portion 301 and the galvanic anode 308 via the second coupling portion 307.

[0074] The resilient biaser 302 is operable to receive the rod 122 of the metal structure 120 between the at least two resiliently deformable members 303, 304. The at least two resiliently deformable members are configured to be deformed by the rod 122 when the rod 122 is received.

[0075] As shown in Figure 3f, when the rod 122 of the metal structure is received, the at least two resiliently deformable members 313, 314 may come into contact with the rod 122 of the metal structure 120 and during the act of receiving the rod 122 the at least two resiliently deformable members 313, 314 may experience a force exerted on them by the rod 122. This force exerted by the rod 122 may cause the at least two deformable members to resiliently deform.

[0076] The resilient deformation of the resiliently deformable members may cause potential energy to be stored by the resiliently deformable members as the force exerted on the deformable members is in opposition to the resilient biasing of the deformable members.

[0077] For example, the resiliently deformable members 303 and 304 illustrated in Figure 3c have a relaxed state, as shown, when they are not acted on by external forces. If the resiliently deformable members are resiliently deformed from this state, for example by experiencing external forces applied by a body, they will act to return to this state under a resilient restoring force. In order to return to their relaxed state from a resiliently deformed state, the resiliently deformable members may exert an elastic force as a result of their bias to return to their relaxed state. This may cause an elastic restoring force to be exerted by the resiliently deformable members on the rod 122.

[0078] In the embodiment shown in Figures 3a and 3f when the rod 122 of the metal structure 120 is received by the resilient biaser 312 of Figure 3a, the resiliently deformable members become subject to external forces that are exerted on the deformable members by the rod 122. Figure 3d illustrates that when the resiliently deformable members are acted on by the metal structure, they are resiliently deformed from their relaxed state to a resiliently deformed, loaded state. An example resilient deformation is illustrated by Figure 3d. The resiliently deformed state illustrated in Figure 3d can be compared with the relaxed state illustrated in Figure 3a, which shows that the deformable member 303 has a first and second portion separated by a given number of degrees, a. When the deformable member 313 is acted on by the rod of the metal structure 120 it is deformed such that the angle between the same first and second portions, d, is decreased with respect to a, as shown in Figure 3d.

[0079] As the resiliently deformable members 313 and 314 have been forced into a loaded position by the metal structure 120, they have been actuated to store potential energy that may be released as an elastic force to at least partially restore the resiliently deformable members towards their relaxed state.

[0080] The actuated resilient bias of the deformable members causes the deformable members to apply a restoring force to the rod 122 of the metal structure, thereby providing a coupling between the first coupling portion of the apparatus and the rod 122 by way of a mechanical connection. The mechanical connection between the first coupling portion 301 of the apparatus 300 and the metal structure 120 may be maintained by the restoring force applied by the resiliently deformable members after the metal structure has been received in order to continuously couple the first coupling portion 301 to the metal structure 120. The continuous coupling ofthe first coupling portion 301 to the metal structure 120 may be provided until the restoring force applied to the metal structure 120 by the resilient biaser 302, through the resiliently deformable members 303, 304, is removed or otherwise counteracted.

[0081] Although the first coupling portion 301 of apparatus 300 illustrated by Figure 3a comprises a plate with an opening, the first coupling portion may alternatively comprise a plate without an opening to be received by at least two of the surfaces of a metal structure which does not comprise a rod. In this case, the deformable members of the resilient biaser may be provided on the outside of the plate.

[0082] The mechanical coupling of the deformable members 303, 304 and the rod 122 of the metal structure 120 illustrated in Figure 3f also provides electrical communication between the metal structure 120 and the first coupling portion 301. A conductive path may also be provided between the first 301 and second 307 coupling portions of the apparatus 300, for example through the plate or directly e.g. through contact between the resiliently deformable members and the galvanic anode or by way of conductive fasteners coupling the deformable members to the galvanic anode, to allow electrical communication between the metal structure 120 and the anode 308 by way of one or more conductive resiliently deformable members of the first coupling portion 301 and the second 307 coupling portion. Electrical communication between the anode 308 and the metal structure 120 may allow the anode 308 to provide corrosion protection to the metal structure 120 by establishing an electrochemical cell, where the sacrificial metal of the galvanic anode is preferentially corroded in favour of the metal of the metal structure, which may be a supporting structure for a pipeline.

[0083] The resiliently deformable members of the resilient biaser of apparatus 300 may allow the apparatus to be deployed to the metal structure without requiring that energy be stored in the resilient biaser prior to the resilient biaser receiving the rod of the metal structure. The apparatus 300 may provide a simplified means of delivering a galvanic anode to a metal structure, which only requires a delivery device, such as a UUV, to provide the apparatus 300 to the metal structure such that the hole of the apparatus 300 receives the rod 122 of the metal structure. This approach may be achieved with a general-purpose inspection class UUV.

[0084] Figure 4a shows the apparatus 300 of Figure 3a releasably connected to an Unmanned Underwater Vehicle, UUV 400. A portion of the UUV 400, which may be a Remotely Operated Vehicle, ROV, is shown in Figure 4a. The ROV 400 may be an inspection class ROV. It will be understood that the UUV 400 may similarly deploy the apparatus 100 or the apparatus 200 to the metal structure 120.

[0085] Figure 4a shows the apparatus 300 being deployed to the metal structure 120 by the UUV 400, where the deployment of the apparatus 300 by the UUV 400 may be achieved without the use of a manipulator arm. The apparatus 300 may be deployed by the UUV 400 by way of a forward driving action 401, where the UUV 400 provides an external force to the apparatus 300 to cause the apparatus to receive the rod of the metal structure within the opening of the apparatus 300. By receiving the metal structure within the opening of the apparatus, the resilient biaser 302 of apparatus 300 may be actuated to cause the resilient biaser to exert a restoring force on the rod of the metal structure, thereby mechanically coupling the apparatus 300 with the metal structure and providing electrical communication between the metal structure and the galvanic anode 308. The electrical communication between the galvanic anode and the metal structure may operatively connect the galvanic anode to the metal structure for corrosion protection of the metal structure.

[0086] The apparatus 300 may be releasably connected to the ROV 400 by way of a releasable connector comprising a pair of tubes 450 coupled to a portion of the ROV 400 and a corresponding pair of co-operating rods 350 coupled to the plate of the apparatus 300, where the tubes 450 are configured to receive the corresponding rods 350 with an interference fit to thereby releasably couple the apparatus 300 to the ROV 400. By virtue of the interference fit, the rods 350 may be configured to slide within the tubes 450 with a level of resistance that may be overcome by a driving force exerted by the ROV 400. The tubes 450 of ROV 400 may be coupled to an inspection equipment channel of the ROV 400.

[0087] In order to install the apparatus 300 on the metal structure, the apparatus 300 may be manually coupled to the ROV 400 by insertion of the rods 350 into the tubes 450, for example before the apparatus and the ROV 400 are deployed. The ROV 400 may then be placed underwater and remotely directed to an underwater location of the metal structure 120. The ROV 400 may then be steered towards the metal structure 120, with the apparatus 300 oriented such that the rod 122 of the metal structure 120 can be received in the opening in the plate of the apparatus 300 to thereby install the apparatus 300 to the metal structure 120. Next, the ROV 400 may be remotely caused to reverse away from the metal structure, thereby removing the rods 350 from the tubes 450 against the interference fit. This is shown in Figure 4b, where the apparatus 300 is installed on the metal structure 120 and the ROV 400 has been directed away from the metal structure 120. It will be understood that the biasing force of the biaser of the apparatus 300 is stronger than the interference fit between the rods 350 and the tubes 450 such that the rods 350 are removed from the tubes 450 in preference to the apparatus 300 being decoupled from the metal structure 120. In the case of apparatus 300 having resiliently deformable members, the apparatus may be further retained on the metal structure during release by way of engagement of the resiliently deformable members with an interfering structure of the metal structure.

[0088] It will be understood that the rods 350 may alternatively be coupled to a portion of apparatus 100 or 200 to couple the apparatus 100,200 to the ROV 400. In this case, the apparatus 100 or 200 may be manually coupled to the ROV 400 by insertion of the rods 350 (which are in this case connected to the apparatus 100 or 200) into the tubes 450 as above and the ROV 400 may then be remotely directed to the underwater location of the metal structure 120 as before. The ROV 400 may then be steered towards the metal structure 120 such that the trigger contact portion (typically the rod 122) of the metal structure 120 contacts the trigger of the trigger mechanism to thereby disengage the separator 113 or the trigger 213 and actuate the biaser 102, 202 to thereby install the apparatus 100 or 200 on the metal structure 120. As before, the biasing force of the biaser of the apparatus 100 or 200 is stronger than the interference fit between the rods 350 and the tubes 450 such that the rods 350 are removed from the tubes 450 in preference to the apparatus 100 or 200 being decoupled from the metal structure 120. In the case of apparatus 100 having a retaining member, the apparatus may be further retained on the metal structure during release by way of the at least one retaining member of the first coupling portion 101.

[0089] Alternatively, apparatus 300 may be releasably connected to the ROV 400 by way of a releasable connector 401, as shown in figures 4c and 4d, comprising a retaining base 402 and a deformable gripping arm 403. The retaining base 402 may be configured to receive a portion of the second coupling portion 307, or in the case of the ring anode the galvanic anode 408. As shown in Figure 4d, the retaining base 402 may comprise a floor 405 and at least two opposing walls 406a, 406b configured to receive the portion of the second coupling portion 307 or anode therebetween. The portion of the second coupling portion 307 may be retained within the base 402 by the deformable gripping arm 403 which may be coupled to a region of the floor 405a of the retaining base 402 offset from the opposing walls 406a, 406b. The deformable gripping arm 403 may be deformed to apply a restoring force to a portion of the second coupling portion 307, or galvanic anode 408, with a directionality to retain the received portion of the second coupling portion within the retaining base 402. The deformable gripping arm 403 may be resiliently deformable. The deformable gripping arm 403 may comprise for example a leaf spring, or an extended deformable member coupled to a coil spring configured to resist removal of the second coupling portion 307 from the retaining base 402. The deformable gripping arm 403 may be resiliently deformed by insertion of the apparatus between the retaining base and the deformable gripping arm prior to deployment by the ROV and may continuously apply a restoring force to the second coupling portion 307, or galvanic anode 408, of the apparatus to retain the apparatus.

[0090] The deformable gripping arm 403 may grip a portion of the second coupling portion 307 or galvanic anode 408 directly, or may for example have a gripping pad, e.g. a rubber sleeve fitted to the gripping end to protect the anode and increase friction between the gripping arm and the anode, and may grip a portion of the second coupling portion or galvanic anode by way of the gripping pad. As shown in Figure 4c, the deformable gripping arm 403 may grip a portion of the second coupling portion 307 or galvanic anode 408 substantially opposing the portion of the second coupling portion or galvanic anode received by the retaining base 402, e.g. the restoring force of the deformable gripping arm 403 may be applied in an on-axis configuration 407a, where the restoring force applied by the deformable gripping arm is substantially perpendicular to the plane of the floor 405 of retaining base. Alternatively, the deformable gripping arm may apply an off-axis 407b restoring force and may be a preferentially left or right-handed configuration such that it grips a portion of the second coupling portion 307 or galvanic anode 408 that is offset to the left or right of a point on the second coupling portion or galvanic anode that opposes the portion of the second coupling portion 307 or galvanic anode 408 received within the retaining base 402, i.e. the restoring force applied by the deformable gripping arm is at an acute or obtuse angle with respect to the plane of the floor 405 of the retaining base. The off-axis configuration of the deformable gripping arm may provide a direct line of sight for e.g. a camera mounted on the deployment ROV for assisting deployment of the apparatus onto the metal structure. The off-axis configuration of the deformable gripping arm may allow for an easier release of the apparatus from the releasable connector.

[0091] The deformable gripping arm 403 may be released from the second coupling portion 307 or the galvanic anode 408 by applying a torque to the releasable connector by the deployment ROV when the apparatus 300 is coupled to the metal structure. The torque applied to the deformable gripping arm 403 by the deployment ROV may deform the deformable gripping arm 403 and displace the gripping arm from its gripped position. The displacement of the deformable gripping arm may release the second coupling portion 307 or galvanic anode 408 from the restoring force exerted by the deformable gripping arm 403 and the second coupling portion 307 or galvanic anode 408 may thus be released from the retaining base. The displacement of the deformable gripping arm 403 and release of the second coupling portion 307 or galvanic anode 408 from the restoring force applied by the deformable gripping arm 403 may release the releasable connector 401 upon deployment of the apparatus. During the release of the apparatus from the metal structure the restoring force of the deformable gripping arm 403 may further facilitate the separation of the apparatus from the connector 401 by applying a force to the apparatus in a direction,

e.g. an off-axis direction 407b, that acts to increase the physical separation between the apparatus and the releasable connector of the ROV.

[0092] Figure 5 is a schematic illustration of a method for operatively connecting a galvanic anode to a metal structure for corrosion protection.

[0093] In 510 a resilient biaser of an apparatus may be actuated. It may be that the resilient biaser is actuated by an ROV 400 being steered to an underwater location of the metal structure, and the ROV 400 being brought into close proximity with the metal structure so as to engage a portion of the apparatus with a portion of the metal structure to thereby actuate the biaser. The actuation may involve a release of potential energy stored in the resilient biaser. The potential energy may be stored by the resilient biaser when an external force, opposing the bias of the biaser, is exerted on the biaser. The potential energy stored by the resilient biaser may be prevented from being released by a trigger mechanism acting on the resilient biaser. The trigger mechanism (where provided) may be actuated to release at least some of the potential energy stored in the biaser. The release of potential energy may be by way of a restoring force exerted by the resilient biaser. In 520, the restoring force exerted by the resilient biaser may couple the first coupling portion of the apparatus to the metal structure. In 530, the coupling of the first coupling portion to the metal structure may electrically connect the anode to the metal structure.

[0094] Figure 6 is a schematic illustration of a method for operatively connecting a galvanic anode to a metal structure for corrosion protection. Figure 6 illustrates a method for connecting the galvanic anode to the metal structure using the apparatus 100 shown in Figure 1a or Figure 1f.

[0095] At 610 the first coupling portion of apparatus 100, which comprises a clamp having a first arm 103 and a second arm 104, receives at least an electrically connecting portion 122 of the metal structure 120 between the first and second arms 103, 104. The apparatus 100 may be caused to receive the electrically connecting portion 122 of the metal structure 120 between the first and second arms 103, 104 by an ROV 400 to which the apparatus 100 is releasably coupled steering the apparatus 100 towards the metal structure 120. The first and second arms 103, 104 of apparatus 100 are held open against a bias applied to the arms from the resilient biaser 102 by a trigger mechanism 109 comprising a separator 113 that is configured to disengage when contact is made between the trigger mechanism 109 and at least a trigger contact portion of the metal structure.

[0096] At 612 the trigger mechanism may be actuated by contact between the trigger mechanism and the said at least a portion of the metal structure.

[0097] At 614 the separator may be disengaged by the actuation of the trigger mechanism and the disengaging of the separator may cause the resilient biaser to be actuated in 616, as the disengaging of the separator 113 releases the hold on the first and second arms. Thus, the clamping ends of the first and second arms 103, 104 may move relative to each other under the bias applied to the arms by the resilient biaser

102.

[0098] At 618 the clamping end of the first arm 103 moves closer to the clamping end of the second arm 104 under the bias of the resilient biaser 102, with the trigger contact portion of the metal structure between the first and second arms. As the clamping end of the first arm 103 moves closer to the clamping end of the second second arm 104 under the bias, the first and second arms 103, 104 may grip the said trigger contact portion of the metal structure between the arms 103, 104. The first and second arms 103, 104 may grip the said trigger contact portion of the metal structure between the arms 103, 104 by way of at least one engaging member at least a portion of which is disposed between the first and second arms. The at least one engaging member being moveable to accommodate the electrically connecting portion of the metal structure.

[0099] At 620, the gripping of the trigger contact portion of the metal structure 120 between the first and second arms 103, 104 provides a coupling between the first and second arms 103, 104 and the metal structure 120 by way of a mechanical connection between the first and second arms 103, 104 of the first coupling portion of apparatus 100 and the metal structure 120. This mechanical connection may be maintained under the bias applied by the resilient biaser 102.The mechanical connection may be further maintained by an overhang of a retaining member of the first coupling portion of the apparatus which may extend across the metal structure between the first and second arms to inhibit removal of the apparatus from the metal structure in a direction substantially opposing a deployment direction of the apparatus onto the metal structure.

[00100] At 630 an electrical connection may be formed between the galvanic anode 108 and the metal structure 120 by way of the mechanical connection between the first and second arms 103,104 of the first coupling portion of the apparatus and the metal structure 120 and an electrically conductive path between the second coupling portion 107 and the clamping end of the first arm 103. It will be understood that 620 and 630 are not typically discrete stages, and that they may be performed simultaneously.

[00101] Figure 7 is a schematic illustration of a method for operatively connecting a galvanic anode 208 to a metal structure 120 for corrosion protection using the apparatus 200 shown in Figure 2a.

[00102] At 710 the first coupling portion of apparatus 200, which comprises a lever 203 and a reference surface 204, with a resilient biaser 202 provided between them, is delivered to the metal structure 120. As discussed above, it may be that the apparatus 200 is delivered to the metal structure 120 by an ROV 400. The delivery of the apparatus 200 to the metal structure may comprise inserting the apparatus 200 between any of the surfaces 121 of the metal structure and the central rod 122. Alternatively, it may be that the metal structure 120 does not contain a central rod, wherein the delivery of the apparatus 200 to the metal structure may comprise inserting the apparatus 200 between any two opposing surfaces 121 of the metal structure 120.

[00103] At 712 the trigger 213 of the trigger mechanism may be disengaged by contact between the trigger 213 and the rod 122 of the metal structure. Alternatively, the trigger 213 may be disengaged by contact between the trigger 213 and any portion of the metal structure 120.

[00104] At 714, the disengaging of the trigger 213 and the subsequent removal of the trigger 213 between the lever 203 of the first coupling portion of the apparatus 200 and the screw 212 of the trigger mechanism, causes the trigger mechanism to be actuated.

[00105] At 716 the actuation of the trigger mechanism causes the actuation of the resilient biaser 202 as the trigger mechanism no longer acts to prevent the release of the potential energy stored in the resilient biaser 202.

[00106] At 718 the actuation of the resilient biaser 202 applies a restoring force between the lever 203 and the reference surface 204 of the first coupling portion of the apparatus 200. The application of the restoring force from the resilient biaser 202 provided between the lever 203 and the reference surface 204 causes the relative distance between the lever 203 and the reference surface 204 to increase.

[00107] At 720 the increase in the relative distance between the lever 203 and the reference surface 204 of the first coupling portion of the apparatus 200 as it is inserted into the metal structure provides a coupling between the metal structure 120 and the apparatus 200 by way of a mechanical connection between the first coupling portion and the metal structure 120. This mechanical connection may be maintained under the bias applied by the resilient biaser 202 provided between the lever 203 and the reference surface 204.

[00108] At step 730 an electrical connection may be formed between the galvanic anode 208 and at least a portion of the metal structure 120 by way of the mechanical connection between the first coupling portion of the apparatus and the metal structure 120, where electrical communication between the galvanic anode 208 and the metal structure 120 may be provided by the second coupling portion of the apparatus 200 and/or by the first coupling portion of the apparatus 200 by way of an electrically conductive path between the second coupling portion (to which the anode 208 is connected) and the first coupling portion. Again, it will be understood that it may be that 720 and 730 are not discrete stages, and that they may be performed simultaneously.

[00109] Figure 8 is a schematic illustration of a method for operatively connecting a galvanic anode 308 to a metal structure for corrosion protection using the apparatus 300 as shown in Figure 3a.

[00110] At 810 the first coupling portion of apparatus 300, which comprises a resilient biaser 302 with at least two resiliently deformable members (at least one of which is electrically conductive) receives at least a portion 122 of the metal structure 120, said portion 122 may be an electrically connecting portion of the metal structure 120. As shown in Figure 3c, the metal structure 120 may comprise a plurality of surfaces provided around a central rod. The receiving of at least a portion of the metal structure between the at least two deformable members of the resilient biaser may comprise receiving the rod 122 of the metal structure 120 into the opening of the apparatus 300 between the at least two resiliently deformable members. The rod 122 of the metal structure 120 may be the at least an electrically connecting portion of the metal structure 120. Alternatively, it may be that the metal structure 120 does not contain a central rod, wherein the apparatus 300 may be delivered to the metal structure by inserting the apparatus 300 between at least two opposing surfaces 121 of the metal structure.

[00111] At 812 receiving the rod 122 between at least two of the deformable members causes at least one of the at least two resiliently deformable members to be resiliently deformed. Alternatively, inserting the apparatus 300 between any two sides 121 of the metal structure may cause at least one of the deformable members to be resiliently deformed if the deformable members are provided on an outside surface of the apparatus 300.

[00112] At 816, the resilient deformation of the resiliently deformable members of the resilient biaser 302 causes the deformable members to change state from a relaxed state to a loaded state in which they store potential energy, thereby actuating the at least two deformable members of the resilient biaser to apply a resilient restoring force towards the rod 122.

[00113] At 818 the at least two deformed members may exert a restoring force on the rod 122 of the metal structure 120. The restoring force may act to grip the rod 122 of the metal structure 120 between the at least two deformable members of the resilient biaser 302.

[00114] At 820 the gripping of the rod 122 of the metal structure 120 between the at least two deformable members of the resilient biaser 302 may result in a mechanical coupling between the apparatus 300 and the metal structure 120 by way of a mechanical connection between the deformable members of the resilient biaser 302 and the metal structure 120. This mechanical connection may be maintained under the resilient bias applied by the resiliently deformable members of the resilient biaser 302. The resiliently deformable members of the resilient biaser may be engageable with an interfering structure of the electrically connecting portion of the metal structure to inhibit removal of the apparatus from the metal structure in a direction opposing the deployment direction of the apparatus on to the metal structure.

[00115] At step 830 an electrical connection may be formed between the galvanic anode 308 and the electrically connecting portion (in this case the rod 122) of the metal structure 120 by way of the mechanical and electrical connection between one or more conductive resiliently deformable members of the resilient biaser 302 of the first coupling portion of the apparatus 300 and the electrically connecting portion of the metal structure 120 and an electrically conducting path between the first and second coupling portions.

While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the scope of this present invention.

Claims

CLAIMS:

1. Apparatus for operatively connecting a galvanic anode to a metal structure for corrosion protection, the apparatus having:

a first coupling portion for coupling the apparatus to the metal structure; and a second coupling portion for coupling the apparatus to the galvanic anode;

wherein the first coupling portion comprises a resilient biaser to be actuated by the metal structure to thereby couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least an electrically connecting portion of the metal structure; and wherein the resilient biaser comprises at least one resiliently deformable member to be deformed by the metal structure to thereby couple the first coupling portion to the metal structure.

2. The apparatus of claim 1, wherein the resilient biaser is configured to couple the first coupling portion of the apparatus to the metal structure and electrically connect the second coupling portion of the apparatus to the electrically connecting portion of the metal structure by way of the first coupling portion of the apparatus by applying a restoring force.

3. The apparatus of claim 1 or claim 2, wherein the resilient biaser comprises at least two resiliently deformable members to receive the electrically connecting portion of the metal structure therebetween.

4. The apparatus of claim 3 wherein the resiliently deformable members are resiliently deformable by the said electrically connecting portion of the metal structure to actuate the deformable members to apply a restoring force on the said electrically connecting portion of the metal structure to thereby couple the apparatus to the metal structure.

5. The apparatus of any of claims 1 to 4 wherein the at least one resiliently deformable member is engageable with an interfering structure of the electrically connecting portion of the metal structure to maintain coupling of the first coupling portion to said electrically connecting portion of the metal structure.

6. The apparatus of claim 5 configured to be deployed onto the metal structure in a deployment direction, and wherein the at least one resiliently deformable member is engageable with the interfering structure of the electrically connecting portion of the metal structure to resist removal of the apparatus in a direction opposing the deployment direction of the apparatus relative to the metal structure.

7. The apparatus of claim 6 wherein resisting removal of the apparatus in a direction opposing a deployment direction of the apparatus relative to the metal structure comprises resisting a slidable motion ofthe apparatus relative to the metal structure.

8. Apparatus for operatively connecting a galvanic anode to a metal structure for corrosion protection, the apparatus having:

wherein the first coupling portion comprises a resilient biaser to be actuated by the metal structure to thereby couple the first coupling portion to the metal structure and electrically connect the second coupling portion to at least an electrically connecting portion of the metal structure;

wherein the first coupling portion comprises at least first and second arms and the first arm is biased towards the second arm by way of a restoring force applied by the resilient biaser;

wherein the resilient biaser is to couple the first coupling portion to the electrically connecting portion of the metal structure by way of at least one engaging member, at least a portion of which is disposed between the first and second arms, the at least one engaging member being moveable relative to the first and second arms to accommodate the electrically connecting portion of the metal structure.

9. The apparatus of claim 8, wherein the resilient biaser is configured to couple the first coupling portion of the apparatus to the metal structure and electrically connect the second coupling portion ofthe apparatus to the electrically connecting portion ofthe metal structure by way ofthe first coupling portion ofthe apparatus by applying a restoring force.

10. The apparatus of claim 9, comprising a trigger mechanism acting on the resilient biaser to prevent the release of potential energy stored by the biaser, and being actuatable to actuate the resilient biaser to apply the restoring force by releasing at least part of the stored potential energy, wherein the trigger mechanism is actuatable by contact with at least a trigger contact portion of the metal structure.

11. The apparatus of claim 10, wherein the trigger mechanism further comprises a separator engaged to hold the first and second arms open against the bias applied by the biaser in order to receive at least the electrically connecting portion of the metal structure between the first and second arms, the separator being configured, upon contact between the trigger mechanism and a or the trigger contact portion of the metal structure, to disengage to thereby actuate the resilient biaser to move the first arm closer to the second arm to grip the electrically connecting portion of the metal structure between the first and second arms.

12. The apparatus of claim 11 wherein, when the electrically connecting portion of the metal structure is gripped between the first and second arms, the second coupling portion of the apparatus is brought into electrical communication with at least the electrically connecting portion of the metal structure by way of at least one of the arms and the at least one engaging member.

13. The apparatus of any of claims 8 to 12 wherein the at least one engaging member of the first coupling portion inhibits decoupling of the apparatus from the metal structure.

14. The apparatus of any of claims 8 to 13 wherein the electrically connecting portion of the metal structure is elongate and the first coupling portion further comprises at least one retaining member to inhibit decoupling of the first coupling portion from the metal structure upon actuation of the resilient biaser in a direction perpendicular to a longitudinal axis of the elongate electrically connecting portion of the metal structure.

15. The apparatus of claim 14 wherein the at least one retaining member comprises an overhang which before actuation of the resilient biaser overhangs an opening between the first and second arms for receiving the electrically connecting portion of the metal structure therebetween and which upon actuation of the resilient biaser is engageable with the electrically connecting portion of the metal structure to inhibit decoupling of the first coupling portion therefrom.

16. The apparatus of any of the preceding claims, wherein the apparatus is configured to be releasably connectable to an Unmanned Underwater Vehicle, UUV.

17. The apparatus of claim 16, wherein said UUV is a remotely operated vehicle, ROV.

18. The apparatus of claim 17, wherein the apparatus is configured to be releasably connectable to a corrosion protection inspection equipment channel of said ROV.

19. A UUV releasably connected to the apparatus of claim 16.

20. A kit of parts comprising the apparatus according to any of claims 1 to 19; and any one or more of: one or more connectors for releasably connecting the apparatus to an Unmanned Underwater Vehicle; a galvanic anode connectable to the second coupling portion of the apparatus.

21. A method for operatively connecting a galvanic anode to a metal structure for corrosion protection, the method comprising:

actuating a resilient biaser of an apparatus comprising the galvanic anode to thereby couple the apparatus to the metal structure and to electrically connect the galvanic anode to an electrically connecting portion of the metal structure;

wherein actuating the resilient biaser comprises deforming by the metal structure at least one resiliently deformable member of the resilient biaser to thereby couple the first coupling portion to the metal structure.

22. A method for operatively connecting a galvanic anode to a metal structure for corrosion protection, the method comprising:

wherein electrically connecting the galvanic anode to the electrically connecting portion of the metal structure comprises coupling by the resilient biaser the first coupling portion to the electrically connecting portion of the metal structure by way of at least one engaging member, at least a portion of which is disposed between the first and second arms, and accommodating the electrically connecting portion of the metal structure by movement of the at least one engaging member relative to the first and second arms.