WO2009004337A2

WO2009004337A2 - Improved damping apparatus

Info

Publication number: WO2009004337A2
Application number: PCT/GB2008/002278
Authority: WO
Inventors: Malcolm Duell
Original assignee: Malcolm Duell
Priority date: 2007-07-03
Filing date: 2008-07-02
Publication date: 2009-01-08
Also published as: GB2450693A; GB0712791D0; GB2450693B; WO2009004337A3

Abstract

A damping apparatus and method of damping for oil or gas recovery or exploration apparatus is described. In an embodiment, the apparatus has a number of resilient bodies which are configured to be received in a space between a conductor guide and a conductor tube received in the conductor guide. The resilient body is further configured to be attached to at least one of the conductor guide and the conductor tube. In a specific embodiment, the resilient bodies are elongate members which are strapped either to the conductor guide or the conductor tube.

Description

Improved Damping Apparatus

The present invention relates to clamping apparatus configured for use with oil or gas recovery or exploration apparatus, and an associated method of damping.

In a number of industries, subsurface wells are drilled to provide for recovery of raw materials. After a fresh well has been drilled, it is usual to install a conductor pipe in the top of the wellbore.

The conductor tube (or conductor casing as it is also known) is cemented in place at the top of the wellbore and secures the open hole to prevent collapse. The bore of the conductor tube provides access to the well and equipment to be used in the well is introduced via the conductor tube. The tube typically comprises thick-walled casing and thus can also provide support for valve tree equipment, which is used in controlling operational conditions of the wellbore.

In offshore applications, the conductor tube usually extends from the top of the wellbore at the seabed to above the sea surface. In such applications, the conductor tube is often installed and supported from a wellhead platform on or above the water surface. The conductor tube may then be guided to the wellbore from the wellhead platform through a series of conductor guide tubes fitted to the platform.

The conductor guide tubes have a greater diameter than the conductor tube to accommodate protrusions on the conductor tube, for example between adjacent conductor tube sections. The conductor guide tubes are usually cylindrical and have a funnel-shaped mouth to provide for ease of reception of a conductor tube in the conductor guide tube. When a conductor tube is installed, the conductor tube is typically located passively within the conductor guide tube. The larger diameter conductor guide tube allows for limited lateral movement of the conductor tube within the conductor guide tube.

There are problems associated with this arrangement. More specifically, the conductor tube is subject to movement caused by wind and sea, which can lead to impacts between the conductor guide tube and the conductor tube, resulting in damage to the conductor tube.

In order to prevent impacts, existing techniques involve use of a clamp arrangement attached to a support member of the platform. In such a case, the clamp typically grips the conductor tube above the guide tube to rigidly secure the conductor tube to the platform in a near-central position within the guide tube.

However, such clamp arrangements are susceptible to damage due to vibrations of the conductor tube caused by the motion of the sea. In addition, installation of such clamp arrangements may require removal of components of the guide tube to secure the clamp in place. For example, the funnel-shaped mouth of the guide tube or "tundish" may need to be removed. Accordingly, installation operations can be time consuming and costly.

Moreover, wave induced movement of the conductor tube can cause large end movements if the conductor tube and the conductor guide tube are rigidly coupled. This can lead to local overstressing of the conductor tube near the rigid coupling points, or for example, in locations where the conductor tube flexes. In other cases, shims are located in the conductor guide tubes to prevent movement of the conductor tube within the conductor guide tube. However, vibrations and movements of the conductor tube caused by the motion of the sea can be transmitted by way of the shims to the conductor guide tube, thereby causing damage to the conductor guide tube and associated equipment.

An improved arrangement that better accommodates movement of the conductor pipe is disclosed in the present applicant's earlier Patent Publication Number GB 2429730. This arrangement has a plurality of resilient balls disposed along the conductor tube in the space between the conductor guide tube and the conductor tube such that movement of the conductor tube is damped. In this arrangement, a containment flange and a top plate are clamped to the conductor tube at opposing ends of the guide tube and protrude radially from the conductor tube to contain the resilient balls in the space.

According to a first aspect of the present invention, there is provided damping apparatus configured for use with oil or gas recovery or exploration apparatus, the damping apparatus comprising: at least one resilient body configured to be received in a space between a conductor guide and a conductor tube received in the conductor guide, the at least one resilient body being further configured to be attached to one of the conductor guide and the conductor tube.

In use, the at least one resilient body may be operable to keep the conductor tube spaced apart from the conductor guide. Also, the at least one resilient body may be operable to damp movement of the conductor tube in relation to the conductor guide. Attachment of the at least one resilient body keeps the resilient body in a predetermined position, for example, longitudinally along the conductor tube, and/or spaced apart around the conductor tube.

More specifically, the at least one resilient body may be configured to be attached to the conductor tube. Attachment of the at least one resilient body to the conductor tube can provide for movement of the resilient body with the conductor tube to provide damping and protection of the conductor tube from impact against the conductor guide.

The damping apparatus may be configured such that in use the at least one resilient member is a snug fit in a space between the conductor tube and conductor guide. Thus, the at least one resilient member may present resistance to movement of the conductor tube through the conductor guide and thereby damp such movement.

More specifically, the at least one resilient body may have a first surface adapted to abut, contact and/or engage the conductor tube, and a second surface adapted to abut, contact and/or engage the conductor guide. The first and second surfaces may be arranged to abut, contact and/or engage the conductor tube and the conductor guide simultaneously, when located in the guide space. The second surface may have a greater curvature than that of the first surface. The first surface may be a concave surface. The second surface may be a convex surface. The first surface of the resilient member may be curved to locate against a curved surface of the conductor tube. Alternatively, the first surface may be substantially flat. The first and second surfaces may together define a outer surface of the resilient body. The at least one resilient body may be adapted to be under compression when located in the guide space such that the body may generate and exert, in use, an expansion force against the conductor guide and/or conductor tube for counteracting, damping and/or resisting movement of the conductor tube relative to the conductor guide.

Alternatively or in addition, the at least one resilient body may be of elongate form and configured such that, in use, the at least one resilient body extends along the conductor tube.

More specifically, the at least one resilient body may have a length of between about 0.1 and 5 metres.

Alternatively or in addition, the damping apparatus may comprise a plurality of resilient bodies, the resilient bodies being configured to be spaced apart when in use around the conductor tube. The resilient bodies may be adapted to, together, centralise the conductor tube with respect to the conductor guide.

Alternatively or in addition, the damping apparatus may comprise an attachment apparatus operable to attach the at least one resilient body to at least one of the conductor tube and conductor guide.

More specifically, the attachment apparatus may comprise an elongate pliable member, e.g. a strap, configured to engage with the at least one resilient body. In another embodiment, the elongate pliable member comprises a metal band.

More specifically, elongate pliable member may be further configured to engage with at least one of the conductor tube and conductor guide. More specifically, elongate pliable member may be further configured to engage with the conductor tube.

More specifically, elongate pliable member may be configured to extend around the conductor tube.

Use of an elongate pliable member, such as a strap or a metal band, can allow the damping apparatus to be quickly and conveniently installed on the conductor tube.

The elongate pliable member may comprise a heavy-duty cargo strap, for example, formed from at least one of nylon, polypropelyne, Kevlar® and any other high-tensile strength material.

The elongate pliable member may comprise a metal band comprising a plurality of band sections joined together via a fastening mechanism, the band sections being joined together towards their respective ends. The fastening mechanism may comprise a nut and bolt arrangement. The fastening mechanism may be engaged to tighten the band around the resilient bodies and/or the conductor pipe.

The elongate pliable member may comprise a tensioning mechanism for tensioning the elongate pliable member when in use. The tensioning mechanism may comprise a ratchet mechanism, and/or a nut and bolt fastening arrangement. Thus by tensioning the elongate pliable member, effective attachment of the damping apparatus to the conductor tube can be achieved. Preferably, the resilient bodies are coupled to each other. The resilient bodies may be coupled to each other via at least one elongate pliable member. The at least one resilient body may comprise at least one engaging formation adapted to engage at least one elongate pliable member.

More specifically, the at least one engaging formation may form part of the at least one resilient body.

More specifically, the at least one engaging formation may be integrally formed with the at least one resilient body.

The engaging formation may take the form of at least one of a slot, an eyelet, a groove, a recess and a clip.

The damping apparatus may be configured when in use for movable engagement of the at least one resilient body in relation to the attachment apparatus. More specifically, the attachment apparatus may slidably engage, e.g. be threaded through, the at least one resilient body.

Where the damping apparatus comprises a plurality of resilient bodies, the damping apparatus may comprise a first elongate pliable member operable to attach the resilient bodies to the conductor tube and a second elongate pliable member operable to couple the resilient bodies to each other. Alternatively or in addition, the second elongate pliable member may be operable to attach the resilient bodies to the conductor tube. In this case, the provision of two elongate pliable members may mean that there is a back up such that the damping apparatus can remain attached to the conductor tube in case of failure of one of the elongate pliable members. Preferably, the at least one resilient body has a shape and/or structure to provide for a pre-specified damping behaviour required of the damping apparatus.

More specifically, the at least one resilient body may be formed from a deformable material. Thus, upon movement of the conductor tube with respect to the conductor guide, the resilient body may deform to accommodate the movement and protect the conductor tube. Being resilient, the material may urge the conductor tube back into its original position and damp the motion. The resilient bodies may be formed from at least one of: a rubber material; a plastics material; and neoprene.

Advantageously, the cross-sectional shape of the resilient bodies may be formed according to a damping characteristic required of the damping apparatus. More specifically, the at least one resilient body may have at least one of a circular, a square, a D-shape and a triangular cross-section.

The at least one resilient body may define a bore. When the damping apparatus is in use, the bore may extend along the conductor tube. In use, the provision of a bore may facilitate deformation of the resilient body when damping movement of the conductor tube with respect to the conductor guide. The bore may extend through the resilient body.

The at least one resilient body may comprise a base member and an extending member. The extending member may, in use, extend radially of the conductor tube between an outer surface of the conductor tube and an inner surface of the conductor guide in the space between the conductor tube and the conductor guide. The base member may, in use, lie proximal the conductor tube. The base member and the extending member may be integrally formed with each other. The base member may extend substantially less from the conductor tube than the extending member, when in use. More specifically, engaging formations may be comprised in the base member.

In particular embodiments, the base member may include the first surface of the resilient member which may abut against an outer surface of the conductor tube. The extending member may include the second surface of the resilient member which may abut against an inner surface of the conductor guide. The extending member and the base member may be formed to together define the outer and/or cross-sectional shape of the resilient body. The cross-sectional shape and/or structure of the resilient body may be further defined in part by the bore. The extending member may be attached to and/or extend from the base member to form a bulb, dome, arced, convex or other shaped second surface for abutting or contacting the conductor guide.

According to a second aspect of the present invention, there is provided oil or gas recovery or exploration apparatus comprising a damping apparatus according to the first aspect of the present invention.

More specifically, the oil or gas recovery or exploration apparatus comprises a conductor guide defining a guide space; a conductor tube received within the guide space and spaced apart from the conductor guide; and the damping apparatus disposed in a space between the conductor guide and the conductor tube.

Embodiments of the second aspect of the present invention may comprise at least one feature of the first aspect of the invention. According to a third aspect of the present invention there is provided a seabed installation comprising oil or gas recovery or exploration apparatus according to the second aspect of the present invention.

Embodiments of the third aspect of the present invention may comprise at least one feature of the first aspect of the invention.

According to a fourth aspect of the present invention, there is provided an offshore platform comprising oil or gas recovery or exploration apparatus according to the second aspect of the invention.

According to a fifth aspect of the invention, there is provided a method of damping for oil and gas recovery or exploration apparatus, the method comprising the steps of:

(a) receiving a conductor tube in a guide tube;

(b) locating a resilient member in a space between the conductor guide and the conductor tube; and

(c) attaching at least one resilient member to one of the guide tube and the conductor tube.

More specifically, the method may be applied for damping movement of the conductor tube in relation to the conductor guide, and may include spacing the conductor tube from the conductor guide.

The step (b) may include spacing a plurality of resilient members around the conductor tube.

The step (b) may include temporarily supporting the resilient members in position prior to performing the step (c) to attach the resilient member. According to a further aspect of the present invention, there is provided damping apparatus configured for use with oil or gas recovery or exploration apparatus, the damping apparatus comprising: at least one resilient body configured to be received in a space between a conductor guide and a conductor tube received in the conductor guide.

More specifically, the at least one resilient body may be further configured to be attached to at least one of the conductor guide and the conductor tube.

There will now be described, by way of example only, embodiments of the invention with reference to the following drawings, of which:

Figure 1 is a perspective representation of a conductor pipe damping arrangement according to an embodiment of the invention;

Figure 2 is a cross-sectional representation of the conductor pipe damping arrangement of Figure 1 ;

Figure 3 is a perspective view of a resilient body for the conductor pipe damping arrangement of Figures 1 and 2; and

Figure 4 is a cross-sectional representation of a conductor pipe damping arrangement according to a further embodiment of the invention; and

Figure 5 is a cross-sectional representation of a conductor pipe damping arrangement according to a further embodiment of the invention. With reference firstly to Figure 1 , there is depicted oil and gas recovery or exploration apparatus 10. The apparatus 10 includes a conductor guide 12, which is attached via a brace 13 to a cross beam 14 forming part of the infrastructure of an offshore platform. The conductor guide 12 is tubular in nature having a tubular main body ("barrel") 15 and a funnel shaped mouth 17 ("tundish"). The conductor guide 12 defines a guide space 16 through which a conductor pipe 18 is received. The apparatus 10 has a number of resilient bodies 20 located around the outside of the conductor pipe 18 in the space between the conductor pipe 18 and the conductor guide 12. The resilient bodies 20 form a damping apparatus, which functions to damp lateral and vertical components of movement of the conductor pipe 18 with respect to the conductor guide 12 due to forces imparted to the conductor pipe by ocean waves and currents. In turn, impact damage to the conductor pipe is prevented.

In Figure 1 , the resilient bodies 20 are elongated and extend along the conductor pipe 18 and through the guide space 16 from a top end 22 through to the bottom end 24 of the apparatus. Further, the resilient bodies 20 are attached to the conductor pipe 18 via a strap 26, which is provided around the resilient bodies tightening them against the conductor pipe 18. Accordingly, the resilient bodies 20 are allowed to move together with the conductor pipe 18.

The provision of elongated bodies allows for proper damping performance at different vertical offsets of the conductor pipe with respect to the guide tube. Vertical offsets seen at the conductor tube/ conductor guide arrangement may occur for example where ocean currents impart lateral forces causing the conductor pipe to bend. The resilient bodies 20 are formed from a rubber material, which is deformable to enable it to damp movement and absorb vibrations imparted by the conductor tube 18. Upon movement of the conductor pipe 18 conductor pipe exerts forces against the adjacent bodies 20 causing them to deform.

As indicated with further reference to Figure 2, there are eight such resilient bodies 20 separated from each other by separate sub-regions 26 of the guide space. Further, each resilient body 20 is provided with a bore or cavity 27 extending longitudinally through the resilient bodies 20.

Deformation of the resilient bodies is accommodated by the cavity 27 and the sub regions 26. Upon movement of the conductor pipe 18 according to arrow 30, the bodies compress and are forced to spread and move into these spaces. Due to the resilient nature of the bodies 20, the conductor pipe 18 is urged back toward a central position within the conductor guide 12. The provision of a number of resilient bodies helps to keep the conductor central within the guide 12. In this way, the present apparatus provides efficient damping of movement and vibrations and protects against impacts and damage to the conductor pipe.

In the embodiment of Figures 1 and 2, the damping apparatus is provided with two straps, which are used to attach the damping apparatus to the conductor tube 18. A first strap 26 mentioned briefly above fits around an outer surfaces defined by tongue portions 34 of the resilient bodies. A second strap 28 is fitted above the first strap, around the conductor tube and is also tightened around it to secure the damping apparatus to the conductor pipe 18. Thus, having two straps provides a back up if one of the straps should fail. In this case, the second strap 28 is also provided to couple the resilient bodies 20 to each other. The strap 28 is threaded through the individual bodies to connect them to each other. As can be seen in more detail in Figure 3, the resilient bodies 20 are provided with slots 32, which are designed to receive the strap 28 for threading and coupling the resilient bodies 20 together. By threading the strap 28 through the bodies, joining portions 29 of the strap 28 are exposed at the surface which prevents the first strap 26 from sliding off and past the second strap 28.

The use of straps 26 and 28 provides for easy installation of the damping apparatus on the conductor pipe. The coupling straps are heavy-duty cargo straps formed from a high strength Kevlar® material, which is resistant to wear and allows the straps to be tensioned to the degree required for attachment. The straps are also provided with a ratchet mechanism used to tension the strap around the resilient bodies 20 and the conductor pipe. The ratchet mechanism is operated manually to tighten the straps allowing personnel to readily attach and install the damping apparatus. The strap may also be provided with a quick-release fastening mechanism for allowing the strap to be easily slackened and removed if required.

The tongue portions 34 (constituting a base member) have a lesser diameter compared with a diameter defined by damping element portions 36 (constituting an extending member). The tongues 34 are comparatively thin and flexible such that the straps can be tightened against the strap surfaces 38 such that they define a tight circumference and such that the tongues are effectively pressed against the conductor pipe. This facilitates securing the resilient bodies to the conductor pipe 18. Turning now to Figure 4, there is shown generally at 1 10 another subsurface recovery or exploration apparatus comprising a clamping apparatus 111. The apparatus 110 has a number of similar features to that of the apparatus 10 of the above described embodiment, and like features are denoted with the same number incremented by 100.

In the Figure 4 embodiment, the resilient bodies 120 of the damping apparatus are attached to the conductor pipe 118 via straps applied at upper and lower ends 140, 142 of the apparatus. The resilient bodies 120 are provided with upper and lower tongue portions 134, 135 around which there the straps 150,152 are fitted to attach the damping apparatus to the conductor pipe. In this case, all of the straps are fitted around the outer surface of the tongue portions 134,135, in a similar manner to the strap 26 of the embodiment of Figures 1 to 3.

In another embodiment, Figure 5 shows generally oil and gas or exploration apparatus 210, which is provided with damping apparatus 211. The apparatus 210 has a number of similar features to that of the apparatus 10 described above, and like features are denoted with the same number incremented by two hundred.

In this embodiment however, the resilient bodies 220 are attached to the conductor pipe 218 by way of upper and lower metal bands 290, which are tightened around the resilient bodies to fasten them to the conductor pipe 218. The metal bands 290 are received in circumferential recesses 292 formed in the resilient body.

The resilient members 220 extend through the guide space and through the main body ("barrel") 295 and mouth ("tundish") 297 portions of the conductor guide 212. The resilient bodies 220 are fitted such that they abut an inner surface of the barrel and an outer surface of the conductor pipe 218.

In this example, each metal band is formed from four sections that are joined together across opposing mating faces 294,296 of adjacent sections and fastened with nut and bolt fastenings 298. The band is flexible such that it can be tightened effectively to force and compress the deformable resilient members in the recess and against the conductor pipe.

Progressive tightening of the nut and bolt fastenings 298 reduces the diameter of the band and allows it to be tensioned and clamped around the resilient bodies and conductor pipe.

The nut and bolt fastenings can be engaged or released manually by personnel, using hand tools if necessary, and can be installed quickly. Sections of the metal band can be interchanged as required, for example to form a band of a different length or circumference.

The metal is 5 mm thick and is selected to have a specification that meets industrial standards and/or tolerances as required.

In practice, the resilient members are introduced to and positioned appropriately in the space between the conductor tube and the conductor guide. The members are successively located in the space. To help position them correctly, each of the members may be temporarily tied off to a nearby component of the rig, for example with a piece of rope, or are supported in some other way. The next member is introduced and tied off in similar way until the full set of resilient members are in place. When all of the resilient members are in position, the resilient members are then attached to the conductor tube using the strap or other attachment apparatus, and the temporary tie off is removed. The apparatus is then prepared and functional to damp relative movement between the conductor guide and conductor tube.

There are a number of advantages associated with the presently described oil and gas recovery or exploration apparatus. In particular, the use of straps or flexible bands to attach the damping apparatus to the conductor pipe enables the damping apparatus to be installed readily by rig personnel. This reduces the time spent to install such apparatus, and can reduce costs.

Further, lateral and vertical components of movement of the conductor pipe within the conductor guide is accommodated and damped out reducing risk of damage to the conductor pipe and the conductor guide.

Furthermore, by using a strap to threadably couple individual resilient bodies together, or using a band formed from a number of sections, individual components can be changed out, replaced and added if required, for example, for maintenance purposes or to construct a suitable device for installation on conductor pipes of different diameter. This can also produce costs benefits.

Various modifications and changes may be made within the scope of the invention herein described. In particular, it will be appreciated that in certain embodiments, the damping apparatus is attached to the conductor guide rather than the conductor tube. In other embodiments, a butterfly clip may be used for attachment of the resilient bodies.

Claims

1. Damping apparatus configured for use with oil or gas recovery or exploration apparatus, the damping apparatus comprising: at least one resilient body configured to be received in a space between a conductor guide and a conductor tube received in the conductor guide, the at least one resilient body being further configured to be attached to one of the conductor guide and the conductor tube.

2. Apparatus as claimed in claim 1 , wherein the at least one resilient body is configured to be attached to the conductor tube.

3. Apparatus as claimed in claim 1 or claim 2, wherein the at least one resilient body is operable to damp movement of the conductor tube in relation to the conductor guide.

4. Apparatus as claimed in any one of claims 1 to 3, wherein the at least one resilient body is operable to keep the conductor tube spaced apart from the conductor guide.

5. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body is of elongate form and configured such that, in use, the at least one resilient body extends along the conductor tube.

6. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body has a length of between about 0.1 and 5 metres.

7. Apparatus as claimed in any one of the preceding claims, wherein the damping apparatus has a plurality of resilient bodies, the resilient bodies being configured to be spaced apart when in use around the conductor tube.

8. Apparatus as claimed in claim 5, wherein the resilient bodies together are operable to centralise the conductor tube with respect to the conductor guide.

9. Apparatus as claimed in any one of the preceding claims, wherein the damping apparatus has an attachment apparatus operable to attach the at least one resilient body to at least one of the conductor tube and conductor guide.

10. Apparatus as claimed in claim 9, wherein the attachment apparatus has an elongate pliable member configured to engage with the at least one resilient body.

11. Apparatus as claimed in claim 10, wherein the elongate pliable member is further configured to engage with one of the conductor tube and conductor guide.

12. Apparatus as claimed in claim 10 or claim 11 , wherein the elongate pliable member is further configured to engage with the conductor tube.

13. Apparatus as claimed in any one of claims 10 to 12, wherein the elongate pliable member is configured to extend around the conductor tube.

14. Apparatus as claimed in any one of claims 10 to 13, wherein the elongate pliable member comprises a heavy-duty cargo strap.

15. Apparatus as claimed in any one of claims 10 to 14, wherein the elongate pliable member comprises a metal band.

16. Apparatus as claimed in any one of claims 10 to 15, wherein the elongate pliable member includes a tensioning mechanism for tensioning the elongate pliable member when in use.

17. Apparatus as claimed in any one of claims 10 to 16, wherein the tensioning mechanism comprises a ratchet mechanism.

18. Apparatus as claimed in any one of claims of claims 10 to 17, wherein the tensioning mechanism includes a fastening mechanism adapted to engage the elongate pliable member.

19. Apparatus as claimed in any one of claims 7 to 18, wherein the resilient bodies are coupled to each other.

20. Apparatus as claimed in claim 19, wherein the resilient bodies are coupled to each other via at least one elongate pliable member.

21. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body includes at least one engaging formation adapted to engage at least one elongate pliable member.

22. Apparatus as claimed in claim 21 , wherein the at least one engaging formation forms part of the at least one resilient body.

23. Apparatus as claimed in claim 21 or claim 22, wherein the at least one engaging formation is integrally formed with the at least one resilient body.

24. Apparatus as claimed in claim 21 to 23, wherein the engaging formation takes the form of at least one of a slot, an eyelet, a groove, a recess and a clip.

25. Apparatus as claimed in any one of the preceding claims, wherein the damping apparatus is configured when in use for movable engagement of the at least one resilient body in relation to the attachment apparatus.

26. Apparatus as claimed in claim 25, wherein the attachment apparatus slidably engages the at least one resilient body.

27. Apparatus as claimed in any of claims 7 to 26, wherein the damping apparatus comprises a first elongate pliable member operable to attach the resilient bodies to the conductor tube and a second elongate pliable member operable to couple the resilient bodies to each other.

28. Apparatus as claimed in claim 27, wherein the second elongate pliable member is operable to attach the resilient bodies to the conductor tube.

29. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body has at least one of a shape and a structure to provide for a pre-specified damping behaviour required of the damping apparatus.

30. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body is formed from a deformable material.

31. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body is formed from at least one of: a rubber material; a plastics material; and neoprene.

32. Apparatus as claimed in any one of the preceding claims, wherein the cross-sectional shape of the resilient bodies is formed according to a damping characteristic required of the damping apparatus.

33. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body has at least one of a circular, a square and a triangular cross-section.

34. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body defines a bore.

35. Apparatus as claimed in any one of the preceding claims, wherein the at least one resilient body includes a base member and an extending member.

36. Apparatus as claimed in claim 35, wherein the extending member, in use, extends radially of the conductor tube between an outer surface of the conductor tube and an inner surface of the conductor guide in the space between the conductor tube and the conductor guide.

37. Apparatus as claimed in claim 35 or claim 36, wherein the base member, in use, lies proximal the conductor tube.

38. Apparatus as claimed in any one of claims 35 to 37, wherein the base member and the extending member are integrally formed with each other.

39. Apparatus as claimed in any one of the preceding claim, wherein the damping apparatus is configured such that in use the at least one resilient member is a snug fit in a space between the conductor tube and conductor guide.

40. Oil or gas recovery or exploration apparatus comprising a damping apparatus according to any one of the preceding claims.

41. Oil or gas recovery or exploration apparatus as claimed in claim 40, wherein the apparatus comprises a conductor guide defining a guide space; a conductor tube received within the guide space and spaced apart from the conductor guide; and the damping apparatus disposed in a space between the conductor guide and the conductor tube.

42. A seabed installation comprising oil or gas recovery or exploration apparatus as claimed in claim 40 or claim 41.

43. An offshore platform comprising oil or gas recovery or exploration apparatus as claimed in claim 40 or claim 41.

44. A method of damping for oil and gas recovery or exploration apparatus, the method comprising the steps of: (a) receiving a conductor tube in a guide tube;

45. A method of damping as claimed in claim 44, wherein the step (b) includes spacing a plurality of resilient members around the conductor tube.

46. A method of damping as claimed in claim 44 or claim 45, wherein the step (b) includes temporarily supporting the resilient members in position in the space.

47. A method of damping as claimed in any one of claims 44 to 46, wherein step (b) is carried out prior to performing the step (c) to attach the resilient member.