[0001] This invention relates to a cable connection assembly, and in particular, to a cable connection assembly that provides a mechanical connection and permits an electrical connection.

BACKGROUND

[0002] Examples of current methods for linking an offshore facility (e.g. a wind farm monopile) with an electrical cable include deep burial of the cable or pulling-in of the cable through a J- tubeless cable entry system.

[0003] Offshore installations are costly, have higher associated risks compared with onshore activities and are more dependent on weather and tidal conditions. For example, when considering offshore wind farms, 40-50% of the total supply chain costs relate to installation costs.

[0004] In addition to increased cost and inconvenience, cables are more likely to be damaged as a result of offshore handling.

[0005] It is an object of certain embodiments of the present invention to provide a cable connection assembly that mitigates some of the problems and disadvantages associated with current systems and methods.

BRIEF SUMMARY OF THE DISCLOSURE

[0006] In accordance with the present invention there is provided a cable connection assembly comprising:

a connector including a main body and a first clamp member; and

a termination member for receiving a part of an armour layer of a cable in which the armour layer is radially outward of one or more conductors of the cable;

wherein the first clamp member is configured to limit axial movement of the termination member relative to the main body; and

the main body includes a plurality of ramped surfaces thereon, a tubular cage surrounding said main body, a plurality of rolling members each captively retained within the apertures of the tubular cage, said tubular cage being axially moveable and biased axially upwardly with respect to said main body, said rolling members being capable of gripping a tubular fixed structure by wedging between said ramped surfaces and an inner surface of said tubular fixed structure. [0007] In certain embodiments , the termination member may be suitable for receiving a wound part of an armour layer of a cable in which the armour layer is radially outward of the one or more conductors of the cable. In certain embodiments, the termination member may be suitable for receiving a part of an armour layer of a cable in which the armour layer is radially outward of the one or more conductors of the cable, where the part of the armour layer is not wound on the termination member. For example, the armour layer may be otherwise received by the termination member. In certain embodiments, the armour layer may be fixed to the termination member by a resin or other adhesive substance.

[0008] The first clamp member may be tubular and include a narrowed portion on an inner surface, where the diameter of the narrowed portion is less than the diameter of the termination member such that the termination member cannot pass through the narrowed portion.

[0009] The narrowed portion may be tapered in an axial direction.

[0010] The first clamp member may comprise a pair of first c-clamp members that are connectable to one another.

[0011] The cable connection assembly may further comprise a stiffening component that is attachable to the connector for providing protection to the cable by limiting the permitted degree of bending of the cable. The stiffening component may be a bend restrictor, where the bend restrictor is a vertebrae bend restrictor (VBR). The cable connection assembly may further comprise a second clamp member for limiting axial movement of the stiffening component relative to the connector. The second clamp member may comprise a pair of second c-clamp members that are connectable to one another.

[0012] The rolling members may be balls.

[0013] The cable connection assembly may further comprise a cable extending along a longitudinal axis and including one or more conductors and an armour layer radially outwards of the one or more conductors, wherein the one or more conductors extend axially beyond the armour layer by an exposed length, and the armoured layer is received on the termination member that is radially outward of the one or more conductors.

[0014] The cable may be a high voltage cable. In certain embodiments, the cable is a 33 kV cable or a 66 kV cable.

[0015] Alternatively, the cable may be an umbilical control line.

[0016] The exposed length may be greater than 1 m and may be less than 100 m. In a particularly preferable embodiment, the exposed length is between 5 and 8 m inclusive.

[0017] In certain embodiments, the exposed length may be sealed in a hermetically sealed environment. The hermetically sealed environment may be a foil-lined bag that is vacuum sealed against the exposed length.

[0018] The cable connection assembly may further comprise a seal between the connector and the exposed length of the one or more conductors.

[0019] The cable connection assembly may further comprise a seal between the armour layer and the one or more conductors. The seal between the armour layer and the one or more conductors may comprise a cured resin.

[0020] The cable may further comprise a polymeric layer radially outward of the armour layer.

[0021] The cable connection assembly may further comprise a collar attach to the polymeric layer, wherein the first clamp member in configured to limit axial movement of the collar relative to the connector.

[0022] In certain embodiments, the armoured layer is wound on the termination member.

[0023] In certain embodiments, the armoured layer is fixed to the termination member and is not wound on the termination member. For example, the armoured layer may be fixed to the termination member by an adhesive substance that is preferably a resin.

[0024] The cable connection assembly may further comprise a tubular fixed structure, and, optionally, may further comprise a seal between the connector and the tubular fixed structure.

[0025] The tubular fixed structure may be fixed to a deck, wherein the deck may be a deck on a monopile of a wind farm.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Embodiments of the invention are further described hereinafter with reference to the accompanying drawings, in which:

Figure 1 is an exploded view of a cable connection assembly, a tubular fixed structure and a vertebrae bend restrictor in accordance with an embodiment of the present invention;

Figure 2 is a perspective view of a cable connection assembly, a bend restrictor with a pulling head attached and a tubular fixed structure prior to connection in accordance with an embodiment of the present invention;

Figure 3A is a side view of a cable connection assembly connected to a tubular fixed structure and a vertebrae bend restrictor in accordance with an embodiment of the present invention;

Figure 3B is a side view corresponding to Figure 3A with the second clamp member in an exploded configuration for clarity; Figure 3C is a side view corresponding to Figure 3A with the second clamp member and vertebrae bend restrictor omitted for clarity;

Figure 4 is a cross section view of the arrangement of Figure 3A;

Figures 5A and 5B are each a cross section view of a part of the main body of the connector where in Figure 5A a roller is in a non-engaging position, and in Figure 5B the roller is in an engaging position;

Figure 6 shows a cross sectional side view of a cable connection assembly according to an alternative embodiment of the present invention; and

Figure 7 shows a cross sectional side view of a termination member and cable in accordance with an alternative embodiment of the present invention.

DETAILED DESCRIPTION

[0027] Figure 1 shows an exploded view of a cable connection assembly 10, a tubular fixed structure 12 and a bend restrictor 14 in accordance with an embodiment of the present invention. The cable connection assembly 10 includes a connector 50, a first clamp member 26, a cable 16, and a second clamp member 36.

[0028] The cable 16 extends along a longitudinal axis 100 and includes a plurality of electrical conductors 24 each sheathed in an insulating layer 24a. Radially outward of the plurality of conductors 24, the cable 16 includes an armour layer 22 that comprises a plurality of metallic wires or strands. The cable 16 may be a medium or high voltage cable (e.g. 33kV or 66kV cable) such as those suitable for use on wind farms. In accordance with an embodiment of the present invention, the armour layer 22 is wound on a termination member 60 (shown in Figure 4) that is radially outward of the plurality of conductors 14 and the plurality of conductors 14 extend axially (i.e. along the longitudinal axis) beyond the wound armour layer 22 and the termination member 60. The extent to which the plurality of conductors 14 extend beyond the wound armour layer 22 will depend on the purpose of the cable 16. For example, if the cable is used on a wind farm monopile, it may be appropriate that the plurality of conductors 24 extend beyond the wound armour layer 22 by approximately 5-8 m (the exposed length). However, it is within the scope of the present invention for the exposed length to be any other suitable length. For example, the exposed length may be greater than 1 m and be less than 100 m. The actual length of the exposed conductors 24 will determine the position and location of the electrical connection between the cable 16 and the electrical infrastructure to which it is connecting.

[0029] In certain emdodiments, the armour layer 22 may be wound on a single ring-like termination member 60 (as shown in Figure 4) where the armour layer 22 is then attached onto itself after passing over the termination member 60. In alternative embodiments, the armour layer 22 may be wound several times onto the termination member 60 and an additional ring- like member may be attached to the termination member 60 to sandwich the wound armour layer between the termination member 60 and the additional ring-like member, where the termination member 60 and additional ring-like member may be attached to one another by bolts and associated nuts, for example.

[0030] Radially outward of the armour layer 22 there is cover layer 18 which may be made of a polymeric material. The armour layer 22 extends axially beyond the cover layer 18 such that the wound armour layer 22 around the termination member is not circumferentially bound by the cover layer 18 and a length of the plurality of conductors 24 is not circumferentially bound by the armour layer 22 or cover layer 18. The cover layer 18 terminates at a collar 20 of the cable 16, wherein the collar 20 includes a circumferential flange 20a projecting radially outwards therefrom.

[0031] The connector 50 includes a main body 52 (see Figure 4) that is tubular and has an inner wall 53 defining a bore. The main body 52 has a lower flange 50a and an upper flange 50b, wherein each of the lower flange 50a and upper flange 50b includes a radially projecting portion. An outer surface of the main body 52 includes a plurality of ramped surfaces 58 thereon. A tubular cage 54 circumferentially surrounds the main body 52 where the cage 54 includes a plurality of apertures 54a corresponding to the number of ramped surfaces 58 of the main body 52 and radially aligned therewith. The cage 54 is axially moveable relative to the main body 52 and is biased axially upwardly relative to the main body 52 by a biasing member 55, which may, for example, be a spring. Each of the apertures 54a of the cage 54 captively retains a rolling member 56 where the radially innermost position of the rolling members 56 is defined by its axial position due to the profile of the ramped surfaces 58.

[0032] Figures 5A and 5B show detailed cross sectional views of the rolling members 56 within the apertures 54a. As shown in Figures 5A and 5B, the ramped surfaces 58 taper radially outwardly in an axially upward direction to a shallow end 58 from a deep end 58b, where the shallow ends 58a are radially outward of the deep ends 58b with respect to the longitudinal axis 100. Figure 5A shows one of the rolling members 56 axially below the shallow end 58a of the ramped surface 58. Figure 5B shows the rolling member 56 at an axial position in which the rolling member 56 is radially aligned with the shallow end 58a of the ramped surface 58. Due to the profile of the ramped surface 58, the rolling member 56 is forced radially outwardly as it is moved axially upwardly (i.e. towards the shallow end 58a). This effect is evident from a comparison of Figures 5A and 5B from which it can be seen that the rolling member 56 of Figure 5B is radially outward of the rolling member of Figure 5A. Since the cage 54 is biased axially upwardly relative to the main body 52, the rolling members 56 are positioned in radial alignment with the shallow ends 58a of the ramped surfaces 58 (i.e. as shown in Figure 5B) in the absence of other external forces acting on the rolling members 56 or cage 54.

[0033] In the embodiment shown in the Figures, the first clamp member 26 comprises a pair of first c-clamp members 26a, b which are connectable to one another with a first set of bolts 34a and a complementary first set of nuts 34b. On an inner surface of each of the pair of first c-clamp members 26a, b is a lower groove 28a, b, an upper groove 32a, b and a narrowed portion 30a, b axially between each lower groove 28a, b and upper groove 32a, b. When the pair of first c-clamp members 26a, b are connected to one another, the lower grooves 28a, b and upper grooves 32a, b form a continuous lower groove 28 and upper groove 32 about the circumference of the inner surface of the first clamp member 26. In the non-limiting

embodiment shown in the Figures, the narrowed portions 30a, b of the pair of first c-clamp members 26a, b form a continuous formation 30 around the entire circumference of the inner surface of the first clamp member 26. In other, less preferable, embodiments, the narrowed portion may be discontinuous around the circumference of the inner surface of the first clamp member 26.

[0034] The lower groove 28 is configured to receive the circumferential flange 20a of the collar 20 so as to limit downward axial movement of the collar 20 relative to the first clamp member 26 (upward axial movement of the collar 20 relative to the first clamp member 26 is also limited by engagement of the circumferential flange 20a in the lower groove 28). Similarly, the upper groove 32 is configured to receive the lower flange 50a of the main body 50 and limit upward axial movement of the main body 50 relative to the first clamp member 26 (downward axial movement of the main body 50 relative to the first clamp member 26 is limited by engagement of the lower flange 50a in the upper groove 32).

[0035] Additionally, the narrowed portion 30 has a minimum diameter that is less than the maximum diameter of the termination member 60 such that armour layer 22 wound onto the termination member 60 (and the termination member 60 itself) cannot pass axially through the first clamp member 26 past the narrowed portion 30. In the non-limiting but preferable embodiment shown in the Figures, the narrowed portion has a tapered profile to match the profile of the wound armour layer 22 on the termination member 60.

[0036] During assembly of the connection assembly 10, the cable 16 is passed axially upwardly through the bore of the connector 50 such that the plurality of conductors 24 extends entirely through the bore. The pair of first c-clamp members 26a, b are connected to one another to form the first clamp member 26 ensuring that the lower flange 50a of the main body 50 is received in the upper groove 32, the termination member 60 (and armour layer 22 wound thereon) is disposed axially above the narrowed portion 30, and the circumferential flange 20a of the collar 20 is received in the lower groove 28. [0037] With the pair of first c-clamp members 26a, b connected to one another in this manner, axial movement of the termination member 60 relative to the main body 50 is limited. Since the armour layer 22 is wound on the termination member 60 which is captive in the first clamp member 26, axial movement of the cable 16 is limited relative to the main body 50. In this configuration, the cable 16 is terminated on and loadably connected to the main body 50.

[0038] It is preferable for the exposed plurality of conducting members 24 to be within the bend restrictor 14 to minimize the degree of possible bending of the conducting members 24 thereby reducing the risk of damage or breakage of the plurality of conducting members 24. In the embodiment shown in Figure 1 , the bend restrictor 14 is a vertebrae bend restrictor (VBR) that is made up of a series of interconnected vertebrae 14a. In other embodiments, any suitable stiffening component that increases the stiffness of the cable 16 may be employed. The bend restrictor 14 has a connecting flange 48 at a lower end for connecting the bend restrictor 14 to the connector 50. A second clamp member 36 is made up of a pair of second c- clamp members 36a, b which each have a channel 38a, b running along its inner surface. When the pair of second c-clamp members 36a, b are connected together, the channels 38a, b form a channel 38 around the entire inner circumference of the second clamp member 36. The channel 38 is configured to receive both the upper flange 50b of the connector 50 and the connecting flange 48 of the bend restrictor 14 so that each of the upper flange 50b and connecting flange 48 are axially captive in the second clamp member 36 and are effectively connected to one another by the second clamp member 36. In the non-limiting embodiment shown in the Figures the pair of second c-clamp members 36a, b are connectable to one another by a second plurality of bolts 40a and associated nuts 40b.

[0039] The assembled connection assembly 10 and connected bend restrictor 14 may be introduced into the tubular fixed structure 12 so as to form a connection between the connector 50 and the tubular structure 12. The bend restrictor 14 may have a pulling head 70 at an upper end for facilitating assembly of the connection assembly 10 to the tubular fixed structure 12. Figure 2 shows an embodiment of the present invention in which the pulling head 70 is attached to the upper end of the bend restrictor 14. In Figure 2, the bend restrictor 14 is not a VBR and represents another embodiment of a bend restrictor in accordance with the present invention.

[0040] The tubular fixed structure 12 may be any tubular structure capable of receiving the connector 50 and having an inner surface corresponding to an outer surface of the main body 50. In the embodiment shown in the Figures, the tubular fixed structure 12 includes a tubular body 42 and a connection flange 44 projecting radially therefrom. The connection flange 44 includes a series of bolt holes 44a for receiving a third plurality of bolts 46a (having

complementary nuts 46b) and connecting the tubular fixed structure to a fixed surface (e.g. part of a monopile of a wind farm). [0041] As the connector 50 is introduced into the tubular body 42, the rolling members 56 contact the inner surface of the tubular body 42 and are pushed axially downwards thereby causing the cage 54 to move axially downwards relative to the main body 52. By moving axially downwards, the rolling members 56 move out of radial alignment with the shallow ends 58a of the ramped surfaces 58 such that the rolling members 56 are permitted to move radially inwardly and permit axial movement of the connector 50 into the tubular body 42.

[0042] At an axial position of the connector 50 relative to the tubular fixed structure 12 where the rolling members 56 are circumferentially surrounded by the tubular body 42, the tension applied to the pulling head 70 may be released or reduced such that the connector 50 experiences a net downward force relative to the tubular fixed structure 12 due to gravity. As a consequence, the main body 52 moves axially downwards by a small amount relative to the tubular fixed structure 12. In doing so, the rolling members 56 roll axially upwards relative to the ramped surfaces 58 to the shallow ends 58a and protrude radially outwards (as shown in Figure 5B). By protruding radially outwards, the rolling members 56 wedge between the ramped surfaces 58 and the tubular body 42 so as to prevent further downwardly axial movement of the connector 50 relative to the tubular fixed structure 12. When the rolling members 56 are in the configuration shown in Figure 5B, the connector 50 is connected to the tubular fixed structure but may be disconnected therefrom by applying an upwardly axial force to the connector 50 which will permit the rolling members 56 to move away from the shallow ends 58a of the ramped surfaces 58 thereby moving radially inwardly and no longer wedging between the tubular fixed structure 12 and the ramped surfaces 58.

[0043] Figures 3A to 3C each show the connection assembly 10 connected to the tubular fixed structure 12. In Figure 3A, the connection assembly 10 is connected to the bend restrictor 14 by second clamp member 36 (36a+36b). Figure 3B shows the apparatus of Figure 3A but with the pair of second c-clamp members 36a, b (of the second clamp member 36) in an exploded configuration and the bend restrictor in a shifted position for clarity. Finally, Figure 3C shows the apparatus of Figure 3A without the bend restrictor 14 or second clamp member 36 for clarity.

[0044] Figure 4 shows a detailed cross sectional view of the apparatus shown in Figure 3A wherein the connection assembly 10 is connected to the tubular fixed structure 12 and the bend restrictor 14. The tubular fixed structure 12 is attached to a fixed surface 200 (e.g. a deck of a wind farm monopile) by the third plurality of bolts 46a and associated nuts 46b.

[0045] Figure 6 shows a connection assembly 1 10 in accordance with an alternative embodiment of the present invention. The connection assembly 1 10 of Figure 6 is largely similar to the connection assembly 10 described above with reference to Figures 1 to 5B.

However, unlike the connection assembly 10 shown in Figures 1 to 4, in the connection assembly 110 of Figure 6, the first clamp member 26 (and hence termination member 60) is arranged axially above the connector 50. As a result, the terminated end of the cable 16 may be accessed from above (i.e. above the tubular fixed structure 12 and any fixed surface 200 that it is attached to). This may be particularly useful in the event that the cable 16 becomes damaged. The damaged cable 16 may be accessed from above, the terminated end of the armour layer 22 may be cut off (e.g. including the termination member 60) and the cable 16 may be withdrawn and replaced, if necessary. Therefore, the cable 16 may be removed without the need to remove or disturb any protection system or structure around the cable 16.

[0046] Figure 7 shows a termination member 60 in accordance with an embodiment of the present invention. The termination member 60 described below in relation to Figure 6 may be employed with any connection assembly according to embodiments of the present invention, including the connection assemblies 10, 110 specifically described above in relation to Figures 1 to 6. In the non-limiting embodiment shown in Figure 7, the termination member 60 extends radially outwardly along an axial direction parallel to the longitudinal axis 100. The first clamp member 26 may have a similarly profiled narrowed portion to receive the termination member 60 and limit axial movement of the termination member 60. In other embodiments, the termination member 60 need not necessarily have a tapered profile.

[0047] The termination member 60 receives the armour layer 22 of the cable 16 and the armour layer 22 is fixed to the termination member 60 by a resin 61. The conductors 24 (and the insulating layers 24a around the conductors 24) pass through the termination member 60. In certain embodiments, the termination member 60 may be any member that receives a part of the armour layer 22 of the cable 16. The armour layer 22 may be fixed to the termination member 60 by any suitable means which may, for example, include any one or combination of winding, adhesive substances including resins, and mechanical fixings.

[0048] When the present invention is employed in subsea or marine environments, it may be preferable to include various seals to limit or prevent the ingress of fluid across the apparatus. For example, there may be a sealing mechanism employed axially below the second clamp member between the connector 50 and the tubular fixed structure 12. There may be a sealing mechanism in an annulus between the plurality of conductors 24 (or rather the insulating layers 24a) and the main body 52 of the connector 50. Additionally or alternatively, there may be a seal between the wound armour layer 22 and the insultating layers 24a in the region of the termination member 60. A suitable seal may be formed by applying a resin to the region (using the so-called "potting" method). Before the bend restrictor 14 is attached to the connection assembly 10, the exposed length of the plurality of conductors 24 (and insulating layers 24a) may be covered with a suitable sealing means. For example, the exposed length may be covered by a hermetically sealed environment which may be foil-lined bag and evacuated by vacuum to ensure a close fitting profile to the plurality of conductors. The bend restrictor 14 may be fitted over the plurality of conductors 14 once the sealing means have been applied.

[0049] All of the seals and sealing means employed will help to prevent the unwanted passage of fluid which may compromise the integrity of the structure to which the fixed tubular member 12 is attached or may lead to fluid (and suspended dirt) ingress into the connection assembly 10 which could lead to damage or failure.

[0050] The present invention as described above provides an efficient and effective means for mechanically connecting a cable 16 to a fixed structure whilst minimizing any risk of cable damage. The present invention is particularly suitable for use in subsea and marine

environments given that the connector 50 may attach to the tubular fixed structure 12 simply by the release or reduction of a load, and may be employed for connecting cables 16 to wind farm monopiles. The cable may be "pre-terminated" (i.e. connected to the connector 50) onshore, thereby avoiding the need to perform this operation offshore with the associated costs, risks and weather conditions. Besides high voltage cables, the present invention may be utilized for umbilical control lines.

[0051] Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to", and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0052] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0053] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.