GB2354751A

GB2354751A - Apparatus and method for positioning subaqueous articles

Info

Publication number: GB2354751A
Application number: GB9923127A
Authority: GB
Inventors: Andrew Gordon Walker; Nicholas Edward Ward; Richard Walker
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-10-01
Filing date: 1999-10-01
Publication date: 2001-04-04
Also published as: WO2001025083A1; AU7536400A; JP2003511298A; EP1216187A1; GB9923127D0

Abstract

The apparatus uses a thrust assembly and a ROV to position equipment underwater. A thrust assembly 1 comprises two thrust units 2,4 mounted on respective ends of e.g. a metal pipe 6 which is suspended in water by lifting rigging 8. The thrust units 2,4 are each connected to a manifold box 10 by hydraulic supply and return tubes 12. The manifold box 10 is centrally mounted on the pipe 6. Extending from the manifold box 10 are hydraulic supply and return tubes 14. The distal end of the a hydraulic supply tube 14 comprises a male coupling element that is received by a corresponding female coupling element of a remote-operational vehicle (ROV) 16. The ROV 16 is suspended in the water distant from the pipe 6 and the thrust units 2,4 and has a camera 20 to aid positioning.

Description

2354751 APPARATUS AND METHOD FOR POSITIONING SUBAQUEOUS ARTICLES The

present invention relates to apparatus and a method for positioning subaqueous articles and is concerned particularly, although not exclusively, with apparatus and a method using power supplied by a remotely operated vehicle for the positioning of subaqueous articles.

Known apparatus for aligning equipment lowered from the ocean surface comprises lifting tackle and guidelines attached to the equipment or supporting framework. The lifting tackle and the guidelines are used to control the position of the equipment. In relatively shallow waters divers use the guidelines to rotate the equipment into the correct orientation. In much deeper waters remote-operational vehicles (ROV) are used. Each ROV is remotely controlled from the surface and comprises a video feedback and one or more articulated arms. The ROV is used to position the equipment using the guidelines. It is very difficult to manoeuvre the ROV and control the orientation of the equipment.

According to a first aspect of the present invention there is provided thrust means for the subaqueous positioning of an article, the arrangement being such that, in use, the thrust means is operated via a remote subaqueous device.

Preferably, the remote subaqueous device supplies power to the thrust means. The thrust means is preferably controlled via the remote subaqueous device.

The thrust means is preferably connected to the subaqueous vehicle by a supply line. A male coupling element and a female coupling element 2 preferably form the connection between the subaqueous vehicle and the supply line.

Preferably the supply line extends from the thrust means, the distal end of the supply line being receivable by the remote subaqueous vehicle.

The distal end of the supply line preferably comprises a mate connection element and the remote subaqueous vehicle preferably comprises a cooperative female connection element.

The remote subaqueous device can be a remote-operational vehicle (ROV) or any other suitable device.

Preferably the thrust means is detachably fixed to the article.

Alternatively, the thrust means is detachably fixed to article-lifting means used to lower the article through the water. The thrust means is preferably mounted on a section fixed to the article-lifting means.

It will be appreciated that the article-lifting means can be any suitable load lifting rigging.

The section attached to the article-lifting means is preferably an adjustable planar section comprising attachment means.

Preferably the planar section comprises attachment means at either end thereof. Alternatively, the planar section comprises two parts, the first part having the attachment means at one end thereof and the second part being free to articulate with respect to the first part.

It is preferable that the thrust means is detachable from the article by direct manipulation.

3 Alternatively, the thrust means is detachable from the article when a remote signal is received by the thrust means.

Preferably, the remote subaqueous vehicle comprises an acoustic transmitter and the thrust means comprises an acoustic receiver, the arrangement being such that, in use, the thrust means is detached from the article when the acoustic transmitter sends a signal to the acoustic receiver.

The thrust means may be electrically powered. Alternatively, the thrust means is hydraulically powered.

Preferably, the thrust means comprises at least one thrust unit comprising a propeller.

In one embodiment of the present invention there is provided a network of thrust means connected to the remote subaqueous device via a manifold or a junction box.

According to a second aspect of the present invention there is provided an assembly for the subaqueous positioning of an article, the assembly comprising thrust means and buoyancy means, the arrangement being such that, in use, when the thrust means is detached from the article the buoyancy means operates to move the thrust means in a direction away 20 from the article.

According to a third aspect of the present invention there is provided a method of positioning a subaqueous article using thrust means, the method comprising operating the thrust means via a remote subaqueous device.

4 The invention may include any combination of the features or limitations referred to herein.

The present invention may be carried into practice in various ways, but two embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure I shows a perspective view of a pair of thrust units mounted on a pipe suspended by lifting rigging and a subaqueous remote-operating vehicle, Figure 2 shows a plan view of the of a pair of thrust units mounted on a piece of equipment suspended on lifting rigging and a subaqueous remote-operating vehicle as shown in Figure 1, Figure 3 shows a plan view of two thrust unit assemblies connected to a subaqueous remote -operating vehicle and lifting rigging disposed above a piece of equipment, Figure 4 shows a side view of the thrust unit assembly and lifting rigging of Figure 3 with the assemblies detached from the subaqueous remote -operating vehicle and disposed above the piece of equipment, Figure 5 shows a perspective view of one of the thrust unit assemblies shown in Figure 4, and Figure 6 shows a side view a thrust unit connected to a central manifold box.

Referring to Figure 1, a first embodiment of the present invention is shown wherein two thrust units 2,4 are mounted on respective ends of a metal pipe 6 which is suspended in water by lifting rigging 8. The thrust units 2,4 are each connected to a manifold box 10 by hydraulic supply and return tubes 12. The manifold box 10 is centrally mounted on the pipe 6. Extending from the manifold box 10 are hydraulic supply and return tubes 14. The distal end of the a hydraulic supply tube 14 comprises a male coupling element that is received by a corresponding female coupling element of a remote-operational vehicle (ROV) 16. The ROV 16 is suspended in the water distant from the pipe 6 and the thrust units 2,4.

In an alternative embodiment of the invention the thrust units are powered by electrical means. The electrical power is supplied by the ROV via a suitable electrical supply line that is 'hot stabbed' into the ROV.

The ROV 16 comprises a tether cable 18, a video camera 20 and a robotic arm 22 with an articulating claw (not shown) at the end of the arm 22. An umbilical cable extends from a vessel on the surface of the water to a intermediate subaqueous frame that contains a junction box and a reel of the tether cable 18 extending therefrom. The umbilical cable 18 comprises power lines and communication lines.

The thrust units 2,4 and the manifold box 10 are mounted on the pipe 6 before the pipe is lowered through the water by the lifting rigging 8. Means used for mounting the thrust units 2,4 and the manifold box 10 onto the pipe may be electromagnetic means or mechanical means such as a releasable clamp assembly.

6 The pipe 6 is lowered through the water until it reaches the seabed or a landing zone. The claw on the articulating arm 22 of the ROV 16 grabs the male coupling element of the supply line 14 and inserts the male coupling into the corresponding female coupling element within the ROV 16 such that there is a watertight seal there between (this is known as hot stabbing).

Hydraulic power is supplied to the thrust units 2,4 from the ROV 16. Hydraulic fluid passes through the supply line 14, the manifold box 10 and the respective tubes 12. The hydraulic supply line 14 comprises a small diameter supply tube and a large diameter return tube. The operator on the surface vessel uses the video camera 20 to view the orientation of the pipe 6. The operator uses a joystick (or other suitable switching/ control mechanism) to send control signals to the ROV 16 in order to operate the respective thrust units 2,4.

A first degree of orientation of the pipe 6 is in the circular rotational directions 24 (either clockwise or anti -clockwise). The pipe 6 rotates about the vertical axis of the lifting rigging 8. The first degree of orientation is achieved when the thrust units 2,4 drive in opposing directions. A second degree of orientation of the pipe 6 is in the arcuate direction 26. The second degree of orientation is achieved when the thrust units 2A drive in the same direction such that the pipe 6 swings on the lifting rigging 8. The curve of the arc 26 will depend upon the length of the lifting rigging 8 because this substantially defines the radius of the arc 26.

When the pipe 6 is correctly positioned the ROV 16 removes the male coupling of the supply line 14 from the female coupling of the ROV 16. The lifting rigging 8, the thrust units 2,4 and the manifold box 10 are then removed from the pipe 6 and are lifted back to the surface. The 7 thrust units 2A and the manifold box 10 may be released from the pipe 6 by mechanical means, for example by the remote arm of ROV 16, or remotely by a signal sent from the operator. The signal may cause the opening of hydraulic locking mechanisms so releasing the thrust units 2,4 5 and manifold box 10 from the pipe 6.

Additional buoyancy is provided for the thrust units 2,4 and the manifold box 10 such that when released they float upwardly in a direction away from the positioned article. Once the trust units 2,4 and the manifold box 10 are distant from the pipe the lifting rigging 8 takes the thrust units 2A and the manifold box 10 to the surface where they can be mounted on a further section of pipe. The ROV 16 remains below the surface and can be used to provide power and control means to a second set of thrust units whilst the first set of thrust units are being mounted onto the further section of pipe.

Referring to Figure 2, the thrust units 2,4 and respective equipment described herein above are being used to position a large piece of subaqueous equipment 30. The thrust units 2,4 are mounted on the piece of equipment and the equipment 30 is being positioned within a pipe run 32.

Referring to Figures 3 to 5, a second embodiment of the present invention is shown. Some features of this embodiment are substantially the same as those described with reference to Figures 1 and 2 of the accompanying drawings and therefore similar reference numerals have been used to describe similar components and further description will not be given. However, with this particular embodiment the two thrust units 2A are each attached to a rectangular mounting board 34. The length between end sections 36 of each mounting board 34 may be adjustable in 8 order to fit pieces of equipment of various sizes. The two thrust units 2, 4 are connected to each other by a hydraulic tube 33.

Each mounting board 34 comprises a central planar section 35 and two detachable clamping end sections 36. Each detachable clamping end section 36 is formed with a circular slot through which a lifting rigging cable 40 passes. A pair of bolts 42 clamps the end sections 36 onto the cable 40. Disposed on the cable 40 directly below each end section 36 are three tubular buoyancy sections 44. At the lowermost end of the respective buoyancy sections 44 is an attachment mechanism 46. The four attachment mechanisms 46 operate to attach the lifting rigging cable 40 to four lifting lugs 50 which extend from the respective four corners of the uppermost surface of the equipment 48 being positioned. The four attachment mechanisms 46 each comprise an acoustic receiver used to operate the mechanism 46.

In use the four attachment mechanisms 46 are fixed onto the four lugs 50 whilst the equipment is above the surface of the water. The equipment and thrust units 2,4 are then lowered through the water using the lifting rigging 8. Once at the correct depth an ROV 16 is remotely controlled to take the male coupling element of the supply line 14 and insert it into the corresponding female coupling element within the ROV 16. The thrust units 2,4 being powered by the ROV 16 are used to manoeuvre the equipment into the correct position. Once this has been achieved the operator will release the male coupling of the supply line from the female coupling by use of the ROV articulated arm 22. The mechanisms 46 are then released via a signal from the ROV 16. The ROV 16 transmits an acoustic signal 52 to the mechanisms 46. On receiving the acoustic signal 52 the mechanisms 46 disconnect from the lugs 50.

9 After the mechanisms 46 have been disconnected from the lugs 50 the buoyancy 44 lifts the thrust units 2,4 away from the equipment 48. The tubular buoyancy sections 44 possess sufficient buoyancy to lift the mounting board 34 and thrust units 2,4 upwardly clear of the positioned article. The thrust units 2,4 are brought to the surface of the water by the lifting tackle where they are retrieved and used for a further piece of equipment.

Referring to Figure 5, the manifold box 10 may comprise a plurality of hydraulic supply and return sockets 60 used to supply a plurality of thrust units.

The thrust means can be alternatively powered by electrical means. The electrical power can be conveniently supplied via the ROV or alternatively by a separate power source.

In some situations it may be more convenient for the thrust units 2,4 to be located on the underside of the mounting board 34. Also, the mounting board 34 can comprise two pieces of tubular sections; a first section being partially disposed within a second section. The second section is attached to the lifting rigging and the first section is in reciprocating sliding contact with the second section.

Examples of the type of thrusters that can be utilised for the present invention are SEAEYE SM5 thrusters and Tecnadyne Model 2020 brushless thruster An example of the type of hot stab connectors that can be utilised are the HYDROBOND ATL505/M-08P female connectors and the HYDROBOND ATL605/M-08S male connectors.

Claims

1. Thrust means for the subaqueous positioning of an article, the arrangement being such that, in use, the thrust means is operated via a remote subaqueous device.

2. Thrust means for the subaqueous positioning of an article as claimed in claim 1, wherein the remote subaqueous device supplies power to the thrust means.

3. Thrust means for the subaqueous positioning of an article as claimed in claim 1, wherein the thrust means is controlled via the remote subaqueous device.

4. Thrust means for the subaqueous positioning of an article as claimed in claim 3, wherein the thrust means is connected to the subaqueous vehicle by a supply line.

5. Thrust means for the subaqueous positioning of an article as claimed in claim 4, wherein a male coupling element and a female coupling element form the connection between the subaqueous vehicle and the supply line.

6. Thrust means for the subaqueous positioning of an article as claimed in claim 4 or claim 5, wherein the supply line extends from the thrust means, the distal end of the supply line being receivable by the remote subaqueous vehicle.

7. Thrust means for the subaqueous positioning of an article as claimed in claim 6, wherein the distal end of the supply line comprises a male connection element and the remote subaqueous vehicle comprises a cooperative female connection element.

8. Thrust means for the subaqueous positioning of an article as claimed in any one of the preceding claims, wherein the thrust means is detachably fixed to the article.

9. Thrust means for the subaqueous positioning of an article as claimed in any one of claims 1 to 7, wherein the thrust means is detachably fixed to article-lifting means used to lower the article through the water.

10. Thrust means for the subaqueous positioning of an article as claimed in claim 9, wherein the thrust means is mounted on a section fixed to the article-lifting means.

11. Thrust means for the subaqueous positioning of an article as claimed in claim 10, wherein the section attached to the article-lifting means is an adjustable planar section comprising attachment means.

12. Thrust means for the subaqueous positioning of an article as claimed in claim 11, wherein the planar section comprises attachment means at either end thereof.

13. Thrust means for the subaqueous positioning of an article as claimed in claim 11, wherein the planar section comprises two parts, the first part having the attachment means at one end thereof and the second part being free to articulate with respect to the first part.

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14. Thrust means for the subaqueous positioning of an article as claimed in any one of claims 8 to 13, wherein the thrust means is detached by direct manipulation.

15. Thrust means for the subaqueous positioning of an article as claimed in any one of claims 8 to 13, wherein the thrust means is detachable from the article when a remote signal is received by the thrust means.

16. Thrust means for the subaqueous positioning of an article as claimed in any one of the preceding claims, wherein the remote subaqueous vehicle comprises an acoustic transmitter and the thrust means comprises an acoustic receiver, the arrangement being such that, in use, the thrust means is detached from the article when the acoustic transmitter sends a signal to the acoustic receiver.

17. Thrust means for the subaqueous positioning of an article as claimed in any one of the preceding claims 1, wherein the thrust means is electrically powered.

18. Thrust means for the subaqueous positioning of an article as claimed in any one of the preceding claims, wherein the thrust means is hydraulically powered.

19. Thrust means for the subaqueous positioning of an article as claimed in any one of the preceding claims, wherein the thrust means comprises at least one thrust unit comprising a propeller.

20. A network of thrust means as claimed in any one of the preceding claims, wherein the thrust means of the network are connected to the remote subaqueous device via a manifold or a junction box.

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21. An assembly for the subaqueous positioning of an article, the assembly comprising thrust means as claimed in any one of the preceding claims, and buoyancy means, the arrangement being such that, in use, when the thrust means is detached from the article the buoyancy means operates to move the thrust means in a direction away from the article.

22. A method of positioning a subaqueous article using thrust means as claimed in any one of the preceding claims, the method comprising operating the thrust means via a remote subaqueous device.

23. Thrust means substantially as herein described with reference to the 10 accompanying drawings.

24. An assembly for the subaqueous positioning of an article substantially as herein described with reference to the accompanying drawings.

25. A method of positioning a subaqueous article substantially as herein 15 described with reference to the accompanying drawings.