CLADDING

Abstract

A cladding (10) for an elongate member to be deployed underwater includes multiple cladding sections (12, 26) each being configured to receive the elongate member and each having proximal and distal ends configured to engage with longitudinally neighbouring cladding sections (12, 26) enabling a continuous length of the cladding to be constructed from multiple cladding sections. At least one of the cladding sections is provided with a sensor module dock (28) configured to receive and releasably mount a sensor module (30) to the cladding.

Claims

1. A cladding for an elongate member to be deployed underwater, the cladding comprising multiple cladding sections each being configured to receive the elongate member and each having proximal and distal ends configured to engage with longitudinally neighbouring cladding sections enabling a continuous length of the cladding to be constructed from multiple cladding sections, wherein at least one of the cladding sections is provided with a sensor module dock configured to receive and releasably mount a sensor module.

2. A cladding section for use in a cladding to be carried on an elongate underwater member, the cladding section being configured to receive and/or seat upon the elongate member and having proximal and distal ends each configured to couple to a neighbouring cladding section, the cladding section comprising a sensor module dock configured to receive and releasably mount a sensor module.

3. The cladding as claimed in claim 1, wherein the sensor module dock comprises a recess for receiving the sensor module.

4. The cladding as claimed in claim 1, wherein the cladding comprises a moulding and the sensor module dock is integrally moulded in the cladding.

5. The cladding as claimed claim 1, wherein the sensor module dock is configured to mechanically engage with the sensor module to releasably retain it.

6. The cladding as claimed in claim 1, wherein the cladding has a longitudinal axis and in which the sensor module dock comprises a recess extending substantially axially to receive the sensor module along a substantially axial direction.

7. The cladding as claimed claim 1, wherein the cladding has a longitudinal axis and in which the sensor module dock comprises a recess which is radially open to receive the sensor module along a substantially radial direction.

8. The cladding as claimed claim 1, wherein the sensor module dock is configured to receive the sensor module as a snap fit.

9. The cladding as claimed claim 1, wherein the sensor module dock comprises one or more radial upstands.

10. The cladding as claimed in claim 1, wherein the sensor module dock includes a radially outwardly open channel or recess for receiving the sensor module.

11. The cladding as claimed in claim 1 further comprising a strake, and wherein the sensor module dock is aligned with the strake.

12. The cladding as claimed in claim 1, wherein the sensor module dock is configured to receive the sensor module in the manner of a part turn lock.

13. The cladding as claimed in claim 1, wherein the sensor module dock comprises an upstanding male feature for receipt in a complementary female feature of the sensor module.

14. A system comprising the cladding as claimed in claim 1 in combination with a sensor module configured to be received by the sensor module dock, wherein the sensor module comprises a dosed pressure vessel containing at least one sensor, a data logger for logging data from the sensor, an interface for outputting logged sensor data, and a battery arranged to power the sensor and the data logger.

15. The system as claimed in claim 14, wherein the sensor module is retainable frictionally in the sensor module dock.

16. The system as claimed in claim 14, the sensor module is cylindrical and the sensor module dock is complementarily shaped.

17. The system as claimed in claim 14, wherein the sensor module has a handle or other graspable feature to be grasped by an effector of an ROV to facilitate retrieval of the sensor module from the cladding.

18. The cladding section as claimed in claim 2, wherein the sensor module dock includes a recess for receiving the sensor module.

19. The cladding section as claimed in claim 2, wherein the sensor module dock is configured to mechanically engage with the sensor module to releasably retain it.

20. The cladding section as claimed in claim 2, wherein the sensor dock includes one or more radial upstands.

Description

[0021] FIG. 1 depicts a cladding section belonging to the prior art, configured as when it is deployed;

[0022] FIG. 2 depicts the same prior art cladding, in this case in an open configuration;

[0023] FIG. 3 depicts a prior art cladding formed from the cladding section of FIGS. 1 and 2; and

[0024] FIGS. 4 to 13 depict respective claddings embodying the present invention, each differing from the other in relation to the formation of a dock for a sensor module.

[0025] FIGS. 1 to 3 depict a form of cladding 10 for application to an elongate underwater member. In itself this cladding belongs to the prior art but it is able to be used in implementing the present invention, as will be made clear below. The cladding 10 is presented by way of example and not of limitation—the present invention may be implemented using claddings of different form. The cladding 10 forms a continuous sheath to receive and surround an elongate member. It is constructed from multiple cladding sections 12 which in the present example are unitary components having multiple part-cylindrical sections 14 coupled to one another through longitudinally extending edges through flexible and integral portions 16 which form living hinges. The cladding section 12 is moulded in the configuration depicted in FIG. 2, where part-cylindrical portions 14 are each identically oriented to form a somewhat flat shape. This is convenient in that the entire cladding section 12 is able to be formed in—and more significantly released from—a one-piece mold. This is also a convenient configuration for storage and transportation, since the flat cladding sections 12 can be stacked in a compact manner. Each of the part-cylindrical portions 14 in this example carries a curved strake portion 18. In the present example a cladding section 12 comprises three part-cylindrical portions 14 coupled through two living hinges 16, but this may vary in other embodiments.

[0026] By bending the living hinges 16, the cladding section 12 is placed in the closed configuration depicted in FIG. 1, in which the part-cylindrical portions 14 together form a complete cylinder to receive the elongate member (which his not seen in the drawings but may for example have a cylindrical form). In this example the cladding section 12 has a proximal end 20 formed with an enlarged internal diameter and a plain distal end 22, so that the proximal end 20 of one cladding section 12 is able to receive the distal end 22 of another identically formed cladding section 12, enabling longitudinally neighbouring sections to be coupled. Hence a required continuous length of cladding is constructable from a chosen number of cladding sections 12. FIG. 3 shows such a cladding 10, including tension bands 24 which extend around the cladding sections 12 to secure them (a) in the closed configuration, so that they are captive upon the elongate member within and (b) to their longitudinal neighbours. In the assembled cladding 10, the strake portions 18 of neighbouring cladding sections 12 align so that the cladding as a whole has strakes lying on three helical loci, in this particular example.

[0027] In accordance with the present invention, the cladding 10 incorporates cladding sections 26 which are able to couple to longitudinally neighbouring cladding sections 12 and which incorporate a sensor module dock 28 to receive and mount a sensor module 30. In some embodiments every cladding section may incorporate a sensor module dock 28. But in the illustrated embodiments the cladding 10 is formed from a mixture of cladding sections 12 lacking a dock and cladding sections 26 having one.

[0028] In the embodiment depicted in FIG. 4 the cladding section 26a is seen to have a generally cylindrical body 32a which may be formed in the same manner as the cladding section 12, with multiple part-cylindrical portions coupled through living hinges, and which is configured at proximal and distal ends 34, 36 to engage with neighbouring cladding sections 12. But in accordance with the present invention, the cladding section 26 is provided with sensor module dock 28a which comprises a pair of integral shaped upstands 38a, 40a which together define a part-cylindrical recess receiving the sensor module 30. In this example the sensor module 30 is a push fit in the sensor module dock 28a. The recess defined between the upstands 38a, 40a is open in a radially outward direction. At its radially outer extremity the facing part-cylindrical surfaces 42a, 44a of the upstands 38a, 40a converge somewhat. As the sensor module 30 is pushed into the recess, the upstands are resiliently deformed somewhat, and then snap back into place to embrace and retain the sensor module 30.

[0029] The FIG. 4 embodiment takes the form of a VIV mitigation cladding having strakes 18, although in this example the cladding section 26a carrying the sensor module dock 28a lacks strakes.

[0030] This and other forms of the sensor module dock 28 and the sensor module 30 are configured to make deployment and retrieval of the sensor module 30 straightforward using an effector of a remotely operated vehicle (ROV). In the FIG. 4 embodiment the sensor module 30 carries a handle 46 which projects radially with respect to the cladding and is easily graspable by an ROV end effector, which can simply push the sensor module 30 into the dock, or pull the sensor module 30 out of the dock.

[0031] The embodiment depicted in FIG. 5 is similar to that of FIG. 4 in that radial upstands 40b form the sensor module dock 28b, but in this case the sensor module 30 is to be introduced to/withdrawn from the sensor module dock 28b along an axial direction, once more forming a push fit to retain the sensor module 30 in the dock. In this example handle 46b is thus provided on an end of the sensor module 30.

[0032] In the embodiment depicted in FIG. 6 the features forming the sensor module dock comprise a suitably shaped outer surface of the cladding and a tension band 29c extending around the sensor module 30 and around the cladding section 26c. The sensor module 30 may be withdrawn axially from this arrangement.

[0033] In the embodiment depicted in FIG. 7 the sensor module dock 28d carried by the cladding section 26d comprises a radially outwardly open cradle 48d which is separately formed from the main part of the cladding section 26d but secured to it, e.g. through the tension bands 24d. A suitable releasable clamping or locking arrangement is provided to retain the sensor module 30d in the cradle 48d. FIG. 8 depicts a variant in which the cradle is replaced by a dock body 50e having an internal cavity for receipt of the sensor module 30 with an axially facing opening.

[0034] The sensor module dock may be formed by the same features used for mitigation of VIV, or by a variant thereof, and/or it may be aligned with those features. FIG. 9 provides an example in which the sensor module dock 28f is formed by a variant of the strake portion 18 which is split to form two curved leaves 52f to receive and embrace the module. This embodiment may be advantageous hydrodynamically, in that VIV mitigation is not affected by the presence of the dock, but it may also be especially straightforward to mount and deploy e.g. through a stinger, since the continuity of shape of the cladding is little affected by the dock.

[0035] FIG. 10 depicts a variant in which the sensor module dock 28g is again in line with the strakes 18 of the cladding, in this case being formed with a part-circular internal profile into which the sensor module 30 is once more to be snap fitted along a radial direction.

[0036] In the FIG. 11 embodiment the sensor module dock 28h comprises a movable part to releasably retain the sensor module 30. This takes the form of a hinged clamp segment 54h.

[0037] The sensor module dock need not enclose or embrace the sensor module 30 in all embodiments of the invention. FIG. 12 depicts an embodiment of the cladding section 26i in which the sensor module dock 28i comprises a radially upstanding rib 56i for receipt in a complementary channel of the sensor module 30.

[0038] FIG. 13 depicts an embodiment of the invention in which the sensor module 30 is to be twisted to engage and to disengage it to/from the sensor module dock 28j. A shaped channel 58j of the sensor module dock 28j engages a stub or other form of follower (not seen) of the sensor module 30.

[0039] Although the sensor module dock may be integrally formed with the cladding section, it need not be so in all embodiments. Another possibility (not depicted) is that the sensor module dock may comprise some form of band or clamp secured around the cladding. For example, the cladding may have a circumferential groove or trough to receive a clamp carrying the sensor module dock. In this way, the sensor module dock is axially located by the cladding, and can be easily and quickly mounted to it during deployment.

[0040] The sensor module 30 is, in the illustrated embodiments, a self-contained and self-powered unit able to log sensor data and to output it through a suitable interface. It comprises a sealed pressure vessel seen in FIG. 4 to comprise a cylindrical housing. In the illustrated embodiments the handle 46 is of “D” shape, but it could instead comprise for example a “T” bar or a fishtail configuration, either of which is easily graspable by an end effector of an ROV. Sensors provided in or on the sensor module 30 may comprise any of the following, or any combination of the following: [0041] an accelerometer, which may be a MEMs type device. This may be used to sense acceleration of the elongate member 16 directly, or by integration to determine motion of the elongate member or changes of its position, or to sense its orientation with respect to the earth's gravitational field, or any combination of these all of which can be obtained by processing the accelerometer's output. Accelerometry is for example well suited to detection of slug induced or vortex induced vibration; [0042] a temperature sensor; [0043] a pressure sensor, which can for example be used to determine water depth; [0044] a gyroscope or other sensor responsive to angular movement or angular acceleration; [0045] a magnetometer, especially one which is responsive to the earth's magnetic field to determine orientation.

[0046] This list is not exhaustive.

[0047] In certain embodiments the sensor module 30 is intended to be retrieved to enable its logged sensor data to be downloaded for analysis. This does not preclude the possibility that some analysis of the data will be carried out on-board the sensor module 30, which may be desirable e.g. for the sake of data compression.

[0048] A range of data interfaces may be used to enable transfer of data from the sensor module 30 to some external processing system. In shallow water applications wireless data exchange may be provided. The sensor modules 30 may be connected in the form of a wireless computer network. At greater depths this is not possible. A short range data interface may be provided, which may be optical, radio frequency, acoustic or some other form of short range communication, so that data can be retrieved during a visit by an ROV, submersible or diver without actual retrieval of the sensor module 30. In other embodiments the sensor module 30 is to be periodically retrieved enabling it to be interrogated. It may then be serviced, which will typically include replacement or re-charging of batteries, before being deployed subsea once more.