Pipe laying apparatus

Abstract

A tubular installation apparatus (1) including a lay tower (2) mounted to a support structure (4). The lay tower (2) is configured to lower a tubular section along a firing line (L) extending along the lay tower (2). A magazine (3) is removably mounted to the lay tower (2) and configured to be pre-loaded with a plurality of tubular sections. A feed mechanism (23, 25) is configured to feed one or more tubular sections from the magazine (3) to the firing line (L) of the lay tower (2) for connection to the end of a catenary.

Claims

1. A tubular installation apparatus comprising a lay tower mounted to a support structure, the lay tower configured to lower a tubular section along a firing line extending along the lay tower, the lay tower comprising an attachment or joining mechanism configured to attach, join or secure a tubular section fed into the firing line to the end of a catenary, a magazine removably mounted to the lay tower while the apparatus is in use in a laying position, the magazine being configured to be pre-loaded with a plurality of tubular sections and a feed mechanism configured to feed one or more tubular sections from the magazine to the firing line of the lay tower for connection to the end of a catenary, wherein at least part of the lay tower is movable in use between a deployed, laying position for laying tubular sections, and a horizontal loading position for loading the magazine onto the lay tower.

2. The apparatus according to claim 1, wherein the magazine comprises a removable carousel having one or more receptacles for receiving the tubular sections.

3. The apparatus according to claim 2, wherein the carousel comprises a plurality of receptacles about its periphery and the feed mechanism is configured to index to one of a plurality of positions to align one of the receptacles with the firing line.

4. The apparatus according claim 1, wherein the feed mechanism comprises a pipe clamp movable between a retrieval position, in which it is configured to extend into the magazine to retrieve a tubular section, a firing line position, in which an axis of the pipe clamp is on or collinear with the firing line, and a retracted position, in which the pipe clamp is positioned away from the firing line.

5. The apparatus according to claim 1, wherein the magazine is releasably attached to the lay tower by a hydraulic latch and comprises a retention mechanism for retaining the tubular sections in the magazine.

6. The apparatus according to claim 1, wherein at least part of the lay tower is pivotable between the deployed, laying position in which it describes and/or is aligned with the firing line, and the loading position in which it is aligned with a loading shuttle for loading or unloading a magazine.

7. The apparatus according to claim 6, comprising a hydraulic actuator configured to pivot the lay tower between the deployed, laying position and the loading position.

8. The apparatus according to claim 1, comprising a loading shuttle configured to transfer the magazine between a storage location and a loading location in which it can be mounted to the lay tower.

9. The apparatus according to claim 1, comprising a hang-off clamp.

10. The apparatus according to claim 1, wherein the support structure comprises a skid to which the lay tower structure is mounted, and wherein the skid comprises one or more lifting points for connection to a crane.

11. A vessel comprising a tubular installation apparatus according to claim 1.

12. A method of laying one or more tubular sections using a tubular installation apparatus, the tubular installation apparatus comprising a lay tower mounted to a support structure, the lay tower configured to lower a tubular section along a firing line extending along the lay tower, the lay tower comprising an attachment or joining mechanism configured to attach, join or secure a tubular section fed into the firing line to the end of a catenary, a magazine removably mounted to the lay tower while the apparatus is in use in a laying position, the magazine being configured to be pre-loaded with a plurality of tubular sections and a feed mechanism configured to feed one or more tubular sections from the magazine to the firing line of the lay tower for connection to the end of a catenary, wherein at least part of the lay tower is movable in use between a deployed, laying position for laying tubular sections, and a horizontal loading position for loading the magazine onto the lay tower, the method comprising: mounting a magazine pre-loaded with a plurality of tubular sections to a lay tower, feeding a tubular section from the magazine into the firing line of the lay tower for connection to the end of a catenary and configuring the lay tower into a loading position prior to mounting the pre-loaded magazine.

13. The method according to claim 12, comprising moving the lay tower from the loading position to a deployed, laying position for laying tubular sections, with the magazine mounted.

14. The method according to claim 12, comprising attaching a tubular section fed into the firing line of the lay tower to the end of a catenary, lowering the catenary with the attached tubular section and feeding a further tubular section from the magazine to the firing line of the lay tower.

15. The method according to claim 14, wherein once the magazine is at least partially empty, moving the lay tower from the deployed, laying position to the loading position and unmounting the magazine from the lay tower, and wherein moving the lay tower comprises pivoting the lay tower.

16. The method according to claim 15, wherein pivoting the lay tower comprises operating a hydraulic actuator.

17. The method according to claim 14, wherein the catenary is suspended from a hang-off clamp.

18. The method according to claim 12, wherein mounting and/or unmounting the magazine comprises operating a hydraulic latch.

19. The method according to claim 12, comprising transferring a loading shuttle with a pre-loaded magazine from a storage location to a loading location prior to mounting the magazine to the lay tower.

20. The method according to claim 19, comprising transferring the loading shuttle with an at least partially empty magazine from the loading location after unmounting the magazine from the lay tower.

Description

(1) Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:

(2) FIG. 1 is a schematic of an apparatus according to an embodiment of the invention in a deployed position;

(3) FIG. 2 is a side view of a supply module according to an embodiment of the invention;

(4) FIGS. 3a, 3b and 3c are sectional views through supply modules according to embodiments of the invention;

(5) FIG. 4 is a sectional view through a supply module according to an embodiment of the invention;

(6) FIG. 5 is a schematic of the apparatus of FIG. 1 between a deployed position and a loading position;

(7) FIG. 6 is a schematic of the apparatus of FIG. 1 in an alternative deployed position;

(8) FIG. 7 is a schematic of the apparatus of FIG. 1 in a loading position;

(9) FIG. 8 is a schematic of the apparatus of FIG. 1 with a supply module unmounted;

(10) FIG. 9 is a schematic of the apparatus of FIG. 1 installed on a vessel;

(11) FIG. 10 is a schematic of an apparatus according to an embodiment of the invention in a first position and with a hoist deployed;

(12) FIG. 11 is a schematic of the apparatus of FIG. 10 in a first position and with a load suspended by the hoist;

(13) FIG. 12 is a schematic of the apparatus of FIGS. 10 and 11 in a third position and with a load suspended by the hoist;

(14) FIG. 13 is a schematic of the apparatus of FIGS. 10 to 12 in a second position and with a load in a first orientation suspended by the hoist;

(15) FIG. 14 is a schematic of the apparatus of FIGS. 10 to 13 in a second position and with a load in a second orientation suspended by the hoist; and

(16) FIG. 15 is a schematic of an apparatus of FIGS. 1, 5 to 8 or 10 to 13 attached to a lifting apparatus.

(17) Referring now to FIG. 1, there is shown a tubular installation apparatus 1 according to an embodiment of the invention which includes a lay tower 2 having a supply module 3 mounted thereto. The lay tower 2 is pivotally connected to a support structure 4 via linkage 5 configured to pivot the lay tower 2. A loading shuttle 6 is engaged with and configured to traverse the support structure 4. A hang-off clamp 7 is pivotally mounted to the support structure 4 in this embodiment such that the lay tower 2 and hang-off clamp 7 share a common pivot axis.

(18) In FIG. 1, the lay tower 2 is shown in a deployed position in which it is aligned with the firing line L. The firing line L is described by the axis of the hang-off clamp 7. The firing line L describes the line along which tubular sections are laid or pulled. The lay tower 2 and firing line L are perpendicular to the support structure 4 in this configuration. The lay tower 2 is pivotally connected to the support at pivot point 21.

(19) Extending from the second end 22 of the lay tower 2 in the direction of the pivot point 21 is an internal pipe clamp 23. The internal pipe clamp 23 has a first or top position shown in FIG. 1 and a second or lower position in which it lies proximate or adjacent the hang-off clamp 7. The internal pipe clamp 23 also has an intermediate position between the first position and the second position in which it can engage a tubular section fed into the firing line L. The internal pipe clamp 23 is movable between the first, intermediate and second positions.

(20) Mounted to and extending from a first side 2a of the lay tower 2 are a pair of spaced, opposed mounts or mounting pins 24a, 24b. The first mounting pin, or base pin 24a is fixed relative to the lay tower 2 and the second mounting pin 24b is movable relative to the lay tower 2. The second mounting pin 24b is hydraulically actuated in this embodiment. The second mounting pin 24b is configured to pivot about the axis of the lay tower 2 in this embodiment. In some embodiments, the second mounting pin 24b is configured to move along the axis of the lay tower 2. The pair of opposed mounting pins 24a, 24b are collinear.

(21) Mounted to and protruding from a second side 2b of the lay tower 2 is a pipe clamp 25 arranged to close around and grip the outer surface of a tubular section. The pipe clamp 25 is movable between and can take up any of three positions in the present embodiment. The first position is a firing line position in which the axis of the pipe clamp 25 is collinear with the firing line L. The second position is a pipe retrieval/loading position in which the pipe clamp 25 extends into the supply module 3 such that it can retrieve a tubular section from the supply module 3 and/or load a tubular section into the supply module 3. The third position is a retracted position in which the pipe clamp 25 is positioned away from the firing line L. The pipe clamp 25 is configured to traverse all or part of the length of the lay tower 2 in this embodiment from a feed position as shown in FIG. 1 in which it is aligned with the supply module 3 to a hand-off position or take-up position. Between the feed position and hand-off position is a lowered position which allows a tubular section to be connected to a catenary. In the lowered position a tubular section is brought into abutting relationship with the end of a catenary. In some embodiments, in the hand-off position, the pipe clamp 25 lies proximate or adjacent the hang-off clamp 7. In some embodiments, the hand-off position is the lowered position. The pipe clamp 25 is a hydraulic pipe clamp in this embodiment.

(22) In the present embodiment, the pipe clamp 25 provides a feed mechanism arranged to feed a tubular section from the supply module 3 into the firing line L and/or feed a tubular section from the firing line L into the supply module 3. The lay tower 2 also includes a drive mechanism (not shown) which forms part of the feed mechanism in this embodiment. The drive mechanism is in the form of a geared drive mechanism arranged to rotate the supply module 3 when mounted to the lay tower 2.

(23) The supply module 3 (as shown in more detail in FIGS. 2 to 4) is in the form of a magazine in this embodiment. The supply module 3 is rotatably mounted to the lay tower 2 between the mounting pins 24a, 24b such that the mounting pins 24a, 24b are aligned with an axis 31 of the supply module 3. The supply module 3 has an aperture 32 centred on the axis 31 and extending the length of the supply module 3. When mounted on the lay tower 2 the mounting pins 24a, 24b extend into the aperture 32 of the supply module 3.

(24) The supply module 3 has a circular cross section and a cylinder-shaped body in this embodiment. A first end of the supply module 3 has a first securing mechanism 33a that lies substantially flush with an end of the supply module 3. A second securing mechanism 33b protrudes from the other end of the supply module 3. Each of the first and second securing mechanisms 33a, 33b are in in the form of a resiliently biased clamp for facilitating attachment to the lay tower 2.

(25) The supply module 3 has a plurality of receptacles 34 in the form of radial slots arranged around the circumference of the supply module 3 in this embodiment. The receptacles 34 are each configured to receive one or more tubular sections.

(26) The supply module 3 has a retention mechanism in the form of retractable pins 35 (FIG. 4) configured to extend partially across each of the plurality of receptacles 34. FIG. 4 shows the retractable pins 35 in a deployed condition.

(27) The supply module 3 has a further retention mechanism in the form of retainer lips (not shown) located at either end of the supply module 3. In the case of tubular sections having end fittings or pipe joints having a greater diameter than the tubular section, the end fittings or pipe joints abut and are supported by the retainer lips.

(28) FIG. 2 shows an alternative retention mechanism, to that of retractable pins 35, in the form of a pair of spaced retention belts 135 arranged to circumscribe the supply module 3.

(29) Referring back to FIG. 1, the support structure 4 is in the form of a skid in this embodiment and has a first, mounting portion 41 and a second, loading portion 42. The mounting portion 41 has a greater thickness than the loading portion 42. The mounting portion 41 and loading portion 42 are formed separately and connected together in this embodiment.

(30) The mounting portion 41 has a web 43 extending therefrom and to which the lay tower 2 is pivotally mounted. The loading portion 42 has a track 44 described therein and configured to receive the loading shuttle 6. The support structure 4 has a grillage structure (not shown).

(31) The support structure 4 has lifting points (not shown) in this embodiment for attachment to an external lifting apparatus.

(32) The linkage 5 includes a telescopic member 51 pivotally connected at a first end 51a to the first side 2a of the lay tower 2 and pivotally connected at a second end 51b to the first end 52a of a first member 52. A second end 52b of the first member 52 is pivotally connected to the support structure 4. A second member 53 is pivotally connected at a first end 53a to the first member 52 intermediate of its ends 52a, 52b and pivotally connected at a second end 53b to the first side 2a of the lay tower 2. The telescopic member 51 is hydraulically actuated in this embodiment.

(33) The loading shuttle 6 engages the track 44 of the support structure 4. The loading shuttle 6 has wheels 61 in this embodiment to allow for movement of the shuttle 6 along the track 44. The loading shuttle 6 also has a pair of spaced load supports 62. The loading shuttle 6 is shown in a loading location 63.

(34) The hang-off clamp 7 is pivotally mounted to the web 43 of the support structure 4 at pivot point 71. The firing line L extends along the axis of the lay tower 2 and along the axis of the hang-off clamp 7. The axis of the pipe clamp 25 when in the firing line position, the axis of the lay tower 2 and the axis of the hang-off clamp 7 are coaxial when the apparatus 1 is in the deployed condition. The hang-off clamp 7 is in the form of a hydraulic pipe clamp similar to pipe clamp 25 and arranged to close around and grip the outer surface of a tubular section.

(35) Referring now to FIG. 5, there is shown the apparatus 1 with the lay tower 2 in an intermediate position between the deployed position of FIG. 1 and a loading position as shown in FIG. 7. The lay tower 2 forms an acute angle with the support structure 4 in this position. The axis of the lay tower 2 is not aligned with the firing line L as described by the axis of the hang-off clamp 7.

(36) With the lay tower 2 in this position, the telescopic member 51 is in a greater state of retraction relative to the telescopic member 51 of FIG. 1.

(37) Referring now to FIG. 6, there is shown the lay tower 2 in an alternative deployed position to that of FIG. 1. As in FIG. 5, the lay tower 2 forms an acute angle with the support structure 4 when in this position. Further, the telescopic member 51 is in a greater state of retraction relative to the telescopic member 51 in both FIGS. 1 and 5.

(38) In the configuration of FIG. 6, the hang-off clamp 7 has been rotated about pivot point 71 such that the axis of the lay tower 2 is coaxial with the axis of the pipe clamp 25 when in the firing line position and the axis of the hang-off clamp 7. In this configuration, the firing line L forms an acute angle with the support structure 4.

(39) Referring now to FIG. 7, there is shown the lay tower 2 in the loading position. In this position, the lay tower 2 has been rotated about pivot point 21 with the support structure 4 such that it lies parallel to the support structure 4. In this configuration, the axis of the lay tower 2 lies perpendicular to the firing line L as described by the axis of the hang-off clamp 7.

(40) In this configuration, the loading shuttle 6 is in the loading location 63 such that when the lay tower 2 is in the loading position, the pair of load supports 62 are positioned to support the supply module 3 if dismounted from the lay tower 2.

(41) Referring now to FIG. 8, there is shown the lay tower 2 in the loading position as per FIG. 7 with the supply module 3 dismounted and supported by the loading shuttle 6. In this case, the second mounting pin 24b has been rotated about the axis of the lay tower 2 such that it does not obstruct movement of the loading shuttle 6 along the track 44 when the supply module 3 is mounted thereto.

(42) In this configuration, the loading shuttle 6 has been moved along the track 44 away from the mounting portion 41 and such that the first mounting pin 24a no longer engages the aperture 32 of the supply module 3. Referring now to FIG. 9 there is shown the apparatus 1 in the configuration of FIG. 6 mounted on a vessel 9. The storage location 64 is shown where supply modules 3 are stored prior to being transported to the loading location 63.

(43) In use, when laying one or more tubular sections, a supply module 3 having a plurality of tubular sections stored therein is transferred from the storage location 64 to the loading location 63 along the track 44 of the support structure 4 using the loading shuttle 6. During this transfer the retractable pins 35 of the retention mechanism are deployed such that inadvertent falling of tubular sections from the supply module 3 is prevented. Alternatively, any other suitable retention mechanism may be deployed.

(44) With the lay tower 2 in the loading position, the loading shuttle 6 is moved along the track 44 until the first mounting pin 24a engages the aperture 32 of the supply module 3 via the first securing mechanism 33a. Once the first mounting pin 24a is engaged, the second mounting pin 24b is rotated about the axis of the lay tower 2 so as to engage the aperture 32 of the supply module 3 via the second securing mechanism 33b such that the supply module 3 is rotatably mounted between the mounting pins 24a, 24b.

(45) The lay tower 2 is then pivoted relative to the support structure 4 by extending the telescopic member 51 via hydraulic actuation.

(46) The lay tower 2 is pivoted about pivot point 21 from the loading position to a deployed position in which the lay tower 2 axis is collinear with the firing line L described by the hang-off clamp 7.

(47) Once in the deployed position, the supply module 3 is selectively rotated or indexed using the drive mechanism to align one of the receptacles 34 such that a tubular section can be fed from the receptacle 34 to the firing line L. Once in the deployed position, the retractable pins 35 are retracted such that tubular sections can be fed from the supply module 3.

(48) Once a receptacle 34 is aligned, the pipe clamp 25 in the feed position aligned with the supply module 3, is configured into the pipe retrieve/load position such that it can feed a tubular section from the receptacle 34.

(49) In embodiments, the retractable pins 35 associated with a given receptacle 34 are only retracted when said receptacle 34 is aligned, all other retractable pins 35 remaining in a deployed position until their respective receptacle 34 is aligned.

(50) Once the tubular section is gripped by the pipe clamp 25 in the pipe retrieve/load position, the pipe clamp 25 is configured into the firing line position such that the tubular section lies along the firing line L.

(51) The pipe clamp 25 is then moved along the firing line L to a lowered position so as to lower the tubular section until an end of the tubular section contacts or abuts the end of a catenary suspended by the hang-off clamp 7. The tubular section is attached to the end of the catenary by mechanical connection in the present embodiment.

(52) The internal pipe clamp 23 is then lowered from its first position to its intermediate position so as to engage an interior of the tubular section attached to the end of the catenary.

(53) Once the tubular section is attached and the internal pipe clamp 23 engaged, the pipe clamp 25 and the hang-off clamp 7 are disengaged. The internal pipe clamp 23 is configured to take up the weight of the catenary and lower the catenary along the firing line L to the second position of the internal pipe clamp 23. Prior or during lowering of the catenary, the pipe clamp 25 is configured into the retracted position and returned to the feed position.

(54) The hang-off clamp 7 is then re-engaged so as to grip the catenary with the new tubular section attached. The internal pipe clamp 23 is then returned to its first position.

(55) If a given tubular section is the first to be laid, the hang-off clamp 7 is in a disengaged condition and the internal pipe clamp 23 lowers the tubular section through the hang-off clamp 7. Once the internal pipe clamp 23 reaches its second position, the hang-off clamp 7 grips the tubular section and the internal pipe clamp 23 disengages and is returned to its first position.

(56) Another tubular section is fed from the same receptacle 34 as the previous one and the process is repeated. Alternatively, if a given receptacle 34 is exhausted of tubular sections, the supply module 3 is selectively rotated or indexed to align another receptacle 34 such that a further tubular section can be fed into the firing line L and the process is repeated.

(57) Once the supply module 3 is exhausted or at least partially exhausted, the lay tower 2 is pivoted about pivot point 21 relative to the support structure 4 into the loading position via hydraulic actuation of the extendable member 51. The supply module 3 is supported by an empty loading shuttle 6 in the loading location 63.

(58) The second mounting pin 24b is rotated relative to the supply module 3 such that it lies out of the path of the supply module 3 on the loading shuttle 6 when moved along the track 44.

(59) The empty or partially empty supply module 3 is transferred along the track 44 to the storage location 64.

(60) The same or another loading shuttle 6 with a supply module 3 having a plurality of tubular sections is transferred from the storage location 64 to the loading location 63 where it can be attached to the lay tower 2 and the process above is repeated.

(61) Although the apparatus 1 is described as being a tubular installation apparatus 1 for laying one or more tubulars above, this need not be the case. The apparatus 1 may be a tubular recovery apparatus used to pull or recover one or more tubulars, in which case the lay tower 2 becomes a recovery tower 2.

(62) In use, when pulling or recovering one or more tubular sections, an at least part empty or part vacant supply module 3 is transferred from the storage location 64 to the loading location 63 along the track 44 of the support structure 4 using the loading shuttle 6. During this transfer the retractable pins 35 of the retention mechanism are deployed if the supply module is part empty such that inadvertent falling of tubular sections from the supply module 3 is prevented.

(63) With the recovery tower 2 in the loading position, the loading shuttle 6 is moved along the track 44 until the first mounting pin 24a engages the aperture 32 of the supply module 3. Once the first mounting pin 24a is engaged, the second mounting pin 24b is rotated about the axis of the recovery tower 2 so as to engage the aperture 32 of the supply module 3 such that the supply module 3 is rotatably mounted between the mounting pins 24a, 24b.

(64) The recovery tower 2 is then pivoted relative to the support structure 4 about pivot point 21 by extending the telescopic member 51 via hydraulic actuation.

(65) The recovery tower 2 is pivoted from the loading position to a deployed position in which the recovery tower 2 axis is collinear with the firing line L described by the axis of the hang-off clamp 7.

(66) Once in the deployed position, the supply module 3 is selectively rotated or indexed using the drive mechanism to align one of the vacant or partially vacant receptacles 34 such that a tubular section can be fed from the firing line L to the receptacle 34. Once in the deployed position, if the supply module is only partially vacant, the retractable pins 35 are retracted such that tubular sections can be fed to the supply module 3.

(67) With the end of a catenary suspended by the hang-off clamp 7, the internal pipe clamp 23 is moved along the firing line L from its first position to its second position. When in the second position, the internal pipe clamp 23 engages an end of the catenary. With the internal pipe clamp 23 engaged, the pipe clamp 25 and the hang-off clamp 7 are disengaged. The internal pipe clamp 23 takes the weight of the catenary and is moved along the firing line L toward the first position, pulling the catenary along the firing line.

(68) Once at or near the first position, the hang-off clamp 7 is re-engaged so as to grip the catenary. A tubular section is decoupled from the catenary by cutting the length of catenary located between the internal pipe clamp 23 and hang-off clamp 7.

(69) With a receptacle 34 aligned and a tubular section decoupled, the pipe clamp 25 is configured into the pipe retrieval/load position so as to feed the decoupled tubular section from the firing line L into the receptacle 34.

(70) Once a tubular section is fed into the receptacle, the pipe clamp 25 is configured into the retracted position and the process is repeated. If a given receptacle 34 is full, the supply module 3 is selectively rotated or indexed to align another receptacle 34 such that a further tubular section can be fed from the firing line L and the process is repeated.

(71) Once the supply module 3 is full or at least partially full, the recovery tower 2 is pivoted relative to the support structure 4 into the loading position. The supply module 3 is supported by an empty loading shuttle 6 in the loading location 63.

(72) The second mounting pin 24b is rotated relative to the supply module 3 such that it lies out of the path of the supply module 3 on the loading shuttle 6 when moved along the track 44.

(73) The full or partially full supply module 3 is transferred along the track 44 to the storage location 64.

(74) The same or another loading shuttle 6 with a vacant or partially vacant supply module 3 is transferred from the storage location 64 to the loading location 63 where it can be attached to the recovery tower 2 and the process above is repeated.

(75) It will be appreciated by those skilled in the art that several variations to the aforementioned embodiments are envisaged without departing from the scope of the invention. For example, although it is described that the pipe clamp 25 and hang-off clamp 7 are arranged to close around and grip the outer surface of a tubular section, this need not be the case. Instead, either or both pipe clamp 25 and hang-off clamp 7 may be arranged to close around the outer surface of a tubular section such that an end fitting of a tubular section is supported by the pipe clamp, i.e. the end fitting of the tubular section has a greater diameter than that described by the closed pipe clamp.

(76) Additionally, although the feed mechanism is described as being the pipe clamp 25, this need not be the case. Instead, the feed mechanism may be a separate feed mechanism, for example, pair of spaced counter-rotating rollers. Alternatively, the feed mechanism may be in the form of a mechanical arm in the lay tower or recovery tower 2 or a spring-loaded mechanism located within the supply module 3. Additionally, the pipe clamp 25 may receive a tubular section from the separate feed mechanism and be configured to traverse the lay tower or recovery tower 2.

(77) The internal pipe clamp 23 may be an external pipe clamp configured to at least partially extend over an end of a tubular section.

(78) In embodiments, the pipe clamp 25 may be used instead of the internal pipe clamp 23 for lowering or pulling tubular sections along the firing line L. In the case of lowering tubular sections, the pipe clamp 25 is configured into the pipe retrieve/load position so as to grip a tubular section. The pipe clamp 25 is then configured into the firing line position such that the tubular section lies along the firing line L. The pipe clamp 25 is then moved along the firing line L to a lowered position so as to lower the tubular section until an end of the tubular section contacts or abuts the end of a catenary suspended by the hang-off clamp 7. The tubular section is attached to the end of the catenary by mechanical connection in the present embodiment. Once the tubular section is attached, with the pipe clamp 25 still gripping the tubular section, the hang-off clamp 7 is disengaged and the pipe clamp 25 is lowered to the hand-off position such that the entire catenary with the attached tubular section is lowered.

(79) The hang-off clamp 7 is then re-engaged so as to grip the catenary with the new tubular section attached and the pipe clamp 25 is disengaged and configured into the retracted position. In the retracted position, the pipe clamp 25 is returned to the feed position.

(80) If a given tubular section is the first to be laid, the hang-off clamp 7 is in a disengaged condition and the pipe clamp 25 lowers the tubular section through the hang-off clamp 7. Once the pipe clamp 25 reaches the hand-off position, the hang-off clamp 7 grips the tubular section and the pipe clamp 25 disengages, is configured into the retracted position and returns to the feed position.

(81) In the case of pulling tubular sections, with the end of a catenary suspended by the hang-off clamp 7, the pipe clamp 25 is moved along the firing line L from the feed position to the take-up position and is configured into the firing line position. When in the firing line position, the pipe clamp 25 grips the catenary. With the pipe clamp 25 engaged, the hang-off clamp 7 is disengaged and the pipe clamp 25 is moved along the firing line L toward the feed position, pulling the catenary along the firing line.

(82) Once at or near the feed position, the hang-off clamp 7 is re-engaged so as to grip the catenary. A tubular section is decoupled from the catenary by cutting the length of catenary located between the pipe clamp 25 and hang-off clamp 7.

(83) With a receptacle 34 aligned and a tubular section decoupled, the pipe clamp 25 is configured into the pipe retrieval/load position so as to feed the decoupled tubular section from the firing line L into the receptacle 34.

(84) Further, the drive mechanism may be separate to the feed mechanism and instead of being a geared drive it may be belt and pulley type system.

(85) Although the supply module 3 is described as having a retention mechanism in the form of retractable pins 35 or retention belts 135 in combination with pipe lips (not shown), this need not be the case. Instead, the supply module 3 may have any, all or none of retractable pins 35, retention belts 135 and pipe lips (not shown).

(86) Although the tubular section is described as being attached to the end of the catenary by mechanical connection, this need not be the case. Instead, a tubular section may be attached to the end of the catenary by welding or any other suitable means of connection.

(87) Referring now to FIG. 10, there is shown a tubular handling apparatus 100 according to an embodiment of the invention wherein like features to those of tubular installation apparatus and/or tubular recovery apparatus 1 are denoted by like references.

(88) The lay tower 2 is shown in a first position in which it describes an acute angle with the support structure 4. A hoist 8 is located at the second end 22 end of the lay tower 2.

(89) The hoist 8 extends away from the second side 2b of the lay tower 2 in this embodiment. The hoist 8 has a top member 81 having lifting line 82 of fixed length extending therefrom. At the free end of the lifting line 82 is a lifting accessory 83 in the form of a shackle in this embodiment.

(90) A supply module 3 is located below the lifting line 82 on a loading shuttle 6 in the loading location 63 such that a projected line from the lifting line 82 bisects the supply module 3.

(91) Referring now to FIG. 11, there is shown the tubular handling apparatus 100 in the same, first position as per FIG. 10 but with the supply module 3 suspended above the support structure 4 and from the end of the lifting line 82. The lifting accessory 83 is engaged with a lifting point (not shown) located to the centre of the supply module 3.

(92) Referring now to FIG. 12, there is shown the tubular handling apparatus 100 with the supply module 3 suspended from the end of the lifting line 82 and in the third position. In the third position the lay tower 2 extends perpendicularly to the support structure 3. The telescopic member 51 is in a lesser state of retraction than in FIGS. 10 & 11 such that the lay tower 2 is pivoted relative to the support structure 4 about pivot point 21. The supply module 3 is suspended partly over the support structure 4 and partly out with it.

(93) The lay tower 2 has an opening (not shown) through which the supply module 3 extends in the third position such that part of the supply module is suspended over the support structure 4 and partly out with it.

(94) Referring now to FIG. 13, there is shown the tubular handling apparatus 100 mounted on a vessel 9. The tubular handling apparatus 100 is shown with the supply module 3 suspended from the end of the lifting line 82. In this case, the lay tower 2 is in the second position in which it describes an obtuse angle with the support structure 4. The first position and second position are diametrically opposed to one another in the present embodiment.

(95) The telescopic member 51 is in a lesser state of retraction than in FIGS. 10 to 12 and the supply module 3 is suspended out with the support structure 4.

(96) FIG. 13 also discloses a dock 110 with a truck 120 for receiving the supply module 3.

(97) Referring now to FIG. 14, there is shown the tubular handling apparatus 100 as per FIG. 13 mounted to vessel 9 but with the suspended supply module 3 rotated 90 degrees relative to that of FIG. 13.

(98) In use, with the tubular handling apparatus 100 mounted on a vessel 9 and with a supply module 3 located in the loading location 63, the lay tower 2 is configured into the first position in which the hoist 8 is located above the first side 2a of the lay tower 2 and above the supply module 3.

(99) The lifting line 82 extends from the top member 81 such that the lifting accessory 83 can be attached to the supply module 3 at the lifting point (not shown). The lay tower 2 is pivoted relative to the support structure 4 a sufficient amount such that the lifting line 82 can be attached to the supply module 3. Once the supply module 3 is attached, the lay tower 2 is pivoted relative to the support structure 4 so as to lift the supply module 3 above the support structure 4. In the present embodiment, the lifting line 82 is of a length such that the supply module 3 is lifted to a sufficient height such that it will clear any lay tower 2 structure in moving the lay tower 2 from the first position to the second position.

(100) With the supply module 3 attached to the lifting line 82, the telescopic member 51 is hydraulically actuated to reduce its state of retraction and pivot the lay tower 2 relative to the support structure 4. Pivoting the lay tower 2 causes it to move through the third position to the second position. In the second position, the supply module 3 is suspended over the truck 120 on the dock 110 and the hoist 8 is located above the second side 2b of the lay tower 2.

(101) In moving from the first position to the second position, the supply module 3 passes through an opening (not shown) in the lay tower 2. Once in the second position, the lay tower 2 is pivoted a sufficient amount until the supply module 3 is supported on the trailer of the truck 120. The lifting accessory 83 is then detached from the supply module 3.

(102) Although the apparatus 100 is described as transferring a supply module 3 from the first side 2a of the lay tower 2 to the second side 2b of the lay tower 2, this need not be the case. The same process as above may be followed in transferring a supply module 3 or any other object from the second side 2b to the first side 2a, for example when loading onto a vessel 9.

(103) Although the hoist 8 is described as having a lifting line 82 of fixed length extending from a top member 81, this need not be the case. Instead the hoist 8 may comprise a winch. The winch having a drum attached or mounted to the top member and arranged to store a length of lifting line. The lifting line may be payed out from the drum so that it can be attached to the supply module 3. Once the supply module 3 is attached, the hoist 8 may be operated to draw the lifting line in and lift the supply module 3 above the support structure 4 a sufficient amount to clear any lay tower 2 structure.

(104) Once in the second position, the lifting line may be payed out so as to lower the supply module 3.

(105) Alternatively, the hoist 8 may comprise a winch attached to a vessel 9 or to the support structure 4. The hoist 8 may have one or more sheaves attached or mounted to the top member and arranged to receive a lifting line from the winch. The lifting line from the winch is passed around the sheaves and attached to the supply module 3 with the lay tower 2 in the first position. The lifting line may be drawn into the winch so as to lift the supply module, utilising the mechanical advantage provided by the sheaves.

(106) The supply module 3 may be transported by operating the winch in concert with movement of the lay tower 2 from the first position to the second position such that the load remains suspended.

(107) Further, although it is shown that the tubular handling apparatus 100 is used for lifting and transporting a supply module 3, this need not be the case. The tubular handling apparatus 100 may be used to lift and transport any suitable object.

(108) Although it is shown that the supply module 3 is lowered on to the trailer of the truck 120 this need not be the case. Instead, the supply module 3 may be lowered directly on to the ground or any other supporting surface.

(109) Although the tubular handling apparatus 100 is described as transporting an object by pivoting the lay tower 2 from the first position through the third position to the second position by passing the object through an opening in the lay tower 2, this need not be the case. Instead, the lay tower 2 may be rotatable about the axis of the lay tower 2 with a constant orientation about the pivot axis 21.

(110) Further, although the tubular handling apparatus 100 is described as having a lay tower 2, this may also or alternatively be a recovery tower 2.

(111) Referring now to FIG. 15, there is shown a tubular installation apparatus, tubular recovery apparatus or tubular handling apparatus 1, 100 in a collapsed position.

(112) In the collapsed position, the telescopic member 51 is fully retracted, the loading shuttle 6 is locked in place to prevent movement during lifting and all other movable components are locked or secured to prevent inadvertent movement during lifting. A pair of lifting lines 182 from an external lifting apparatus (not shown) are connected to the apparatus 1, 100 at spaced lifting points (not shown).

(113) In the collapsed position, the apparatus 1, 100 forms a transportable, modular structure than can be loaded to and/or unloaded from a vessel (not shown).

(114) It will also be appreciated by those skilled in the art that any number of combinations of the aforementioned features and/or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein.