GB2222215A - Method and apparatus for assembling and removing seal members in sub-sea operations on fluid-carrying pipes. - Google Patents
Method and apparatus for assembling and removing seal members in sub-sea operations on fluid-carrying pipes. Download PDFInfo
- Publication number
- GB2222215A GB2222215A GB8913797A GB8913797A GB2222215A GB 2222215 A GB2222215 A GB 2222215A GB 8913797 A GB8913797 A GB 8913797A GB 8913797 A GB8913797 A GB 8913797A GB 2222215 A GB2222215 A GB 2222215A
- Authority
- GB
- United Kingdom
- Prior art keywords
- pipe end
- seal member
- pipe
- tool
- axially
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L1/00—Laying or reclaiming pipes; Repairing or joining pipes on or under water
- F16L1/26—Repairing or joining pipes on or under water
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Automatic Assembly (AREA)
Abstract
A tool for assembling and/or removing a seal member (1) with or from the sub-sea end of a pipe section (5) comprises a frame (13) for location relative to the pipe end and carrying a device (15, 30) for engaging the seal member, the device being supported in the frame for movement relative to the pipe end between a position in axial alignment with the pipe end for assembling or removing the seal member and a position spaced from the pipe end to permit other operations to be performed on the pipe end. The tool may comprise two devices one for assembling the seal member and one for removing the seal member which are mounted on a mounting member (16) movable transversely of the pipe end between positions aligning one of the devices with the pipe end and a position enabling the support member to be moved axially of the pipe end away from the pipe end without interference with the pipe end. The mounting member (16) is movable transversely of the pipe end relative to a support member (23) which is movable axially relative to the frame. <IMAGE>
Description
Improvements in and relating to a
method and apparatus for carrying
out sub-sea operations on fluid
carrying pipes
The present invention relates to apparatus and a method for carrying out sub-sea operations relating to the sub-sea installation of fluid carrying pipes, for example flow-lines and hydraulic fluid carrying lines.
In connecting sections of sub-sea pipes for carrying fluids, it is desirable to provide seals between the ends of the pipe sections. While such a seal may be associated with one of the pipe ends before the pipe is lowered sub-sea, the seal may be damaged during other operations carried on or in the region of the pipe end before the pipe end is connected to the end of the next pipe section.
According to one aspect of the present invention there is provided a tool for performing operations on or in the region of the sub-sea end of a pipe section comprising apparatus for assembling a seal member with the end of the pipe section comprising a device for carrying the seal member, the device being mounted on the tool for movement axially and transversely of the pipe end between a position away from the pipe end, enabling other operations to be performed on or in the region of the pipe end, and a position in axial alignment with the pipe end for assembly of the seal member with the pipe end.
According to another aspect of the present invention there is provided a method of assembling on the subsea end of a pipe section a seal member for sealing the end of the pipe section to the end of the next pipe section, comprising lowering onto the pipe end a tool for performing operations on or in the region on the pipe end and comprising apparatus for assembling the seal member with the pipe end comprising a device for carrying a seal member, associating a seal member with the device, moving the device transversely and axially of the pipe end from a position away from the pipe end to enable other operations to be performed on or in the region of the pipe end, to a position adjacent the pipe end and in which the seal member is in alignment with the pipe end, and moving the device axially towards the pipe end to assemble the seal member with the pipe end.
The tool may also comprise a device for removing a seal member from the end of the pipe and the removal device may be associated with the introduction device as part of the apparatus.
According to a further aspect of the present invention there is provided a tool for performing operations on or in the region of the sub-sea end of a pipe section comprising apparatus for removing a seal member from the end of a pipe section comprising a device for engaging the seal member, the device being mounted on the tool for movement axially and transversely of the pipe end between a position away from the pipe end, enabling other operations to be performed on or in the region of the pipe end, and a position in axial alignment with the pipe end for removal of the seal member therefrom.
According to yet another aspect of the present invention there is provided a method of removing from the sub-sea end of a pipe section a seal member for sealing the end of the pipe section to the end of the next pipe section, comprising lowering onto the pipe end a tool for performing operations on or in the region of the pipe end and comprising apparatus for removing the seal member from the pipe end comprising a device for engaging the seal member, moving the device transversely and axially of the pipe end from a position away from and out of alignment with the pipe end, to enable other operations to be performed on or in the region of the pipe end, to a position adjacent the pipe end and in which the seal member is in alignment with the pipe end and moving the device axially towards the pipe end to engage the seal member and away from the pipe end to remove the seal member from the pipe end.
The seal member may be formed by a seal or may comprise a seal carrying member which is interposed between the ends of the pipe sections to be connected and which supports one or more seals in position to seal the connection between the pipe ends.
The tool may comprise a frame associated with means for locating the frame relative to the pipe end and the apparatus may be mounted on the frame for movement of the device axially and transversely of the pipe end, the transverse movement being angular or linear.
The apparatus may comprise a mounting member carrying the introduction device and/or the removal device and mounted for transverse movement relative to a support member which is movable axially of the pipe end on the frame. The frame may comprise a plurality of parallel bars on which the support member is slidably mounted, the mounting member being mounted on one of the bars for movement along the bar and about the axis of the bar.
The seal member may be mounted on the device on the surface before the tool is lowered or when the tool has been lowered onto the pipe end using for example an
ROV.
Further features and advantages of the present invention will become apparent from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which:
Figure 1 is a part axial section through the ends of two adjacent pipe sections which have been connected together with the interposition of a seal member according to an embodiment of the present invention;
Figures 2 and 3 are axial sections through embodiments of devices for assembly and removal of the seal member of Figure 1;
Figure 4 is a side elevation showing part of an embodiment of tool according to the present invention; and
Figure 5 is a section on the line V-V of Figure 4.
In this particular embodiment, the seal member 1 (Figure 1) comprises a seal carrying plate 2 which is interposed between the ends 3, 4 of pipe sections 5, 6 to be connected together, and has a central opening 7 in which an AX type seal 8 is located. It will be appreciated that other forms of seal may be provided.
Peripheral flanges 9, 10 are provided projecting axially from the end faces of plate 2 for centering the seal member 1 and seal 8 relative to the ends of the pipe sections 5, 6 which are correspondingly shaped to engage the flanges 9, 10 and seal 8. As shown, the end portions of the pipe sections 5, 6 are provided with radially enlarged hubs 11 (of which only hub 11 of pipe section 6 is shown in Figure 1, pipe section 5 having a similar hub) for engagement by tools for performing operations on and in the regions of the pipe ends.
In the sequence of connection of the ends of the pipe sections 5, 6, pipe section 5 is first fixed to a fixed sub-sea template (not shown) and then operations are required to be performed on or in the region of its end, for example the removal of a cap from the end of the pipe section, by a tool. The tool (Figures 4 and 5) is lowered from the surface and comprises a frame 13 which is provided with means for locating it relative to the hub 11 of the pipe section 5. The frame 13 may comprise the main frame of the tool which seats on the template or may comprise a sub-frame which is mounted on the main frame so as to permit relative movement between the subframe and the main frame. Tools for performing the other operations on or in the region of the end of the pipe section will not be described as they form no part of the invention of this application.
The tool also comprises apparatus 14 for assembling a seal member 1 with the end of the pipe section 5, which apparatus is mounted on the frame 13.
The apparatus 14 comprises a seal member introduction device 15 which is mounted on a mounting member which, as shown, is in the form of a plate 16. The device 15 (Figure 2) comprises an annular array of radially flexible fingers 17 projecting from the plate 16 and for surrounding the seal member 1. The fingers 17 have radially inwardly directed detents 18 on their free ends, which detents 18 engage in a peripheral groove 19 (Figure 1) in the periphery of the seal member 1 to hold the seal member 1 in the device 15. The detents 18 and groove 19 are shaped so that an axial pull on the seal member 1 will detach it from the device 15.
To assemble the seal member 1 with the end of the pipe 5, the introduction device 15 carrying the seal member 1 is brought to a position in axial alignment with the end of the pipe (Figure 4) and is then moved axially towards the pipe end. The flange 9 on the leading end of the seal member 1 ensures that the seal member is axially aligned with the pipe end and continued axial movement of the seal member on the device towards the pipe end brings the seal member fully into engagement with the pipe end. In this position, the seal member 1 is positively engaged with and held on the end of the pipe section 5 by engagement of a snap-ring 20 partially projecting outwardly from a groove 21 in the pipe end, with a corresponding groove 22 in flange 9 of the seal member 1.The axial pull required to detach the seal member 1 from the introduction device 15 is arranged to be less than that required to disengage the snap-ring 20 from groove 22 so that, when introduction device 15 is pulled axially away from the end of the pipe, the device 15 detaches from the seal member 1 leaving the seal member 1 assembled with the pipe end.
To enable other operations to be carried out on the pipe end before and/or after its assembly with the seal member 1, the mounting plate 1 6 carrying device 15 is mounted on the frame so that it can be moved away from the pipe end. As shown the mounting plate 16 is associated with a support member, as shown, in the form of a plate 23. The support plate 23 is mounted for sliding movement on parallel bars 24 which form part of the frame 13 and extend generally parallel to the axis of the pipe end. Movement of the support plate 23 on the bars is obtained by actuation of one or a plurality of double acting hydraulic cylinders 25 mounted between the frame 13 and support plate 23.The plate 23 is thus movable axially of the pipe end and has a generally inverted U-shape comprising arms defining a central opening 26 aligned with but larger than the pipe end and its hub so that the plate 23 can move axially along the pipe with the arms extending on either side of the pipe but without interfering with the pipe or its hub.
The mounting plate 16 has the same overall shape as the support plate 23 with a central opening 27 and arms 28 defining the opening 27. The introduction device 15 is mounted on one of the arms 28. The mounting plate 16 is mounted for movement transversely of the support plate 23 between an inoperative position, as shown in Figure 5, in which its central opening 27 is aligned with that of the support plate, and an introduction position (Figure 4) in which the introduction device 15 on its arm 28 is axially aligned with the pipe end. As shown, the mounting plate 16 is mounted on one of the frame bars 24 for angular movement about the axis of the bar relative to support plate 23. The angular movement may be obtained by a linearly acting hydraulic cylinder (not shown) or by a rotary actuator (not shown) acting between the support and mounting plates.
Detent means (not shown) may be provided acting between the mounting and support plates to positively locate the mounting plate in its inoperative and operative introduction positions relative to the support plate. Such detent means may for example comprise appropriately positioned recesses or depressions in one of the plates for engagement by a resilient or spring biased catch on the other plate.
In use, the tool is lowered into position on the end of pipe 5 with the mounting plate 16 in its inoperative position relative to support plate 23. The seal member 1 may already be engaged in the introduction device 15 or may be engaged with the device when the tool is in position using, for example, an ROV. Until the seal member 1 is to be assembled with the pipe end, the apparatus 14 is positioned axially distant from the pipe end, either inboard or outboard of the pipe end, to enable other operations to be carried out on or in the region of the pipe end. When the seal member is to be inserted, the support plate 23 is moved axially by operation of the or each cylinder 25 to a position adjacent to but spaced outboard from the pipe end.The mounting plate 16 is then swung round relative to the support plate 23 to its operative position in which the introduction tool and seal member are aligned with the pipe end.
The support member 23 is then moved axially towards the pipe end to bring the seal member into engagement with the pipe end as described above. Reverse axial movement of the support plate then detaches the introduction device from the seal member. The mounting member 16 may then be moved back to its inoperative position relative to support member 23 and the support member may be moved further away axially from the pipe end if other operations are to be performed on the pipe end.
The apparatus may also or alternatively include a device 30 (Figure 3) for removing a seal member from the end of the pipe. The device 30 may be used in place of device 15 or, where both devices are provided, the device 30 is mounted on the other arm 28 of the mounting plate 16 and the mounting plate 16 is movable to a third removal position relative to the support plate 23 and in which the removal device 30 is aligned with the pipe end.
The removal device 30 is similar to the insertion device in that it also comprises an annular array of radially flexible fingers 31 projecting from the mounting plate 16, the fingers having radially inwardly directed detents 32 for engaging in the peripheral groove 19 in the seal member 1. However the fingers 31 of the removal device are more heavily sprung than the fingers 17 of the introduction device and the detents 32 have an undercut face shaped so as to positively engage in the groove 19 which is correspondingly undercut. For removal of the seal member 1, the support member is, as before, moved axially to a position adjacent but outboard of the end of the pipe 5 and the mounting member 16 is then moved transversely to its third removal position in which the removal device 30 is aligned with the end of the pipe.The support member is then moved axially towards the pipe end to engage the removal device with the seal member 1, the positive engagement of the detents 32 on the fingers 31 in the groove 19 of the seal member, on reverse axial movement of the mounting and support members, overcoming the engagement force of the snap-ring 20 in the seal member so that the seal member is removed with the removal device.
Although, as described above, the mounting plate 16 is moved angularly relative to the support plate 23, it will be appreciated that it could alternatively be moved linearly. For example it could be mounted to slide linearly on the support plate. The support plate may also form part of another device for performing operations on the pipe end.
As described above, the seal member provides a sealed connection between two sections of a single fluid carrying line. The seal member may alternatively provide a sealed connection between a plurality of sections of a plurality of fluid carrying lines which are, for connection purposes, connected to multi-bore hubs which are to be connected together with the interposition of a corresponding multi-bore seal member.
Under such circumstances, references in the foregoing to the end of a pipe or pipe section should be interpreted as references to the end of the corresponding multi-bore hub.
Claims (24)
1. A tool for performing operations on or in the region of the sub-sea end of a pipe section comprising apparatus for assembling a seal member with or removing a seal member from the end of the pipe section comprising a device for carrying the seal member, the device being mounted on the tool for movement axially and transversely of the pipe end between an inoperative position away from the pipe end, enabling other operations to be performed on or in the region of the pipe end, and a position in axial alignment with the pipe end for assembly of the seal member with the pipe end or removal of the seal member from the pipe end.
2. A tool as claimed in claim 1, wherein the apparatus comprises mounting means carrying the device, the mounting means being movable transversely of the pipe end between a first position in which the device is aligned with the pipe end and a second position in which the device is transversely spaced from the pipe end, means being provided for moving the mounting means transversely of the pipe.
3. A tool as claimed in claim 2, wherein the mounting means are movable axially of the pipe end when the mounting member is in its first position, for moving the device towards and away from the pipe end, and when the mounting member is in its second position, for moving the device to its inoperative position, means being provided for moving the mounting means axially of the pipe.
4. A tool as claimed in either claim 2 or claim 3, wherein the mounting means comprises a generally U-shaped member having two arms defining therebetween a space dimensioned so that the member can be moved axially along the pipe end with the arms positioned one on each side of the pipe without interference with the pipe.
5. A tool as claimed in claim 4, wherein the device is carried by one of the arms and in the first position of the mounting member the one arm is positioned with the device axially aligned with the pipe end and in the second position of the mounting member the arms are positioned one on each side of the pipe.
6. A tool as claimed in any one of the preceding claims, wherein the device is adapted for assembling a seal member with the pipe end.
7. A tool as claimed in claim 5, wherein the device comprises means for resiliently engaging the seal member, the seal member and pipe end having interengaging means which engage with a greater force than that retaining the seal member on the device such that when the seal member is engaged with the pipe end axial movement of the device away from the seal end will detach the seal member from the device.
8. A tool as claimed in any of claims 1 to 5, wherein the device is adapted for removal of a seal member from the end of the pipe section.
9. A tool as claimed in claim 8, wherein the device comprises means for resiliently engaging a seal member, the seal member and pipe end having interengaging means which engage with a lesser force than that by which the seal member is engaged by the device such that when the seal member is engaged by the device it will be disengaged from the pipe end on movement of the device away from the pipe end.
10. A tool as claimed in any of the preceding claims, comprising a first device for assembly of a seal member with the pipe end and a second device for removal of a seal member from the pipe end.
11. A tool as claimed in claim 10, wherein each device comprises means for resiliently engaging the seal member, the seal member and pipe end having interengaging means which engage with a force which is greater than that retaining the seal member on the first device but which is less than that engaging the seal member on the second device.
12. A tool as claimed in either claim 10 or claim 11, wherein the devices are carried one on each arm and the mounting member is movable transversely of the pipe end between a first position in which the device carried by one arm is axially aligned with the pipe end, a second position in which the device carried by the other arm is axially aligned with the pipe end and a third position in which the arms are positioned one on each side of the pipe end.
13. A tool as claimed in any one of claims 2 to 12, wherein the mounting member is movable angularly between its said positions.
14. A tool as claimed in any one of claims 2 to 12, wherein the mounting member is movable linearly between its said positions.
15. A tool as claimed in any of claims 2 to 14, wherein the mounting member is movable transversely of the pipe end relative to a support member, the support member being mounted for movement axially relative to the pipe end, the means for moving the support member transversely of the pipe end acting between the support and mounting members.
16. A tool as claimed in claim 15, wherein the support member is generally U-shaped for positioning relative to the pipe end with the arms of the U one on each side of the pipe end, the space between the arms being dimensioned to permit the support member to move axially along the pipe without interference therewith.
17. A tool as claimed in any of the preceding claims, wherein the tool comprises a frame for location relative to the pipe end, the apparatus being mounted within the frame for movement relative thereto.
18. A tool as claimed in claim 16, wherein the tool comprises a frame for location relative to the pipe end, the support member being mounted on the frame for linear movement relative thereto, means being provided for moving the support member relative to the frame.
19. A tool as claimed in claim 18, wherein the frame comprises a plurality of parallel bars extending generally parallel to the axis of the pipe end, the support member being slidable along the bars and the mounting member being pivotable relative to the support member about the axis of one of the bars.
20. A tool for performing operations on or in the region of the sub-sea end of a pipe section substantially as herein described with reference to the accompanying drawings.
21. A method of assembling on the sub-sea end of a pipe section a seal member for sealing the end of the pipe section to the end of the next pipe section, comprising lowering onto the pipe end a tool for performing operations on or in the region of the pipe end and comprising apparatus for assembling the seal member with the pipe end comprising a device for carrying the seal member, associating the seal member with the device, moving the device transversely and axially of the pipe end from a position away from the pipe end enabling other operations to be performed on or in the region of the pipe end, to a position adjacent the pipe end in which the seal member is in alignment with the pipe end, and moving the device axially towards the pipe end to assemble the seal member with the pipe end.
22. A method of removing from the sub-sea end of a pipe section a seal member for sealing the end of the pipe section to the end of the next pipe section, comprising lowering onto the pipe end a tool for performing operations on or in the region of the pipe end and comprising apparatus for removing the seal member from the pipe end comprising a device for removing the seal member, moving the device transversely and axially of the pipe end from a position away from the pipe end enabling other operations to be performed on or in the region of the pipe end, to a position adjacent the pipe end in which the device is in alignment with the pipe end, and moving the device axially towards the pipe end to engage the seal member with the device.
23. A method as claimed in claim 19 substantially as herein described.
24. A method as claimed in claim 20 substantially as herein described.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB888814368A GB8814368D0 (en) | 1988-06-16 | 1988-06-16 | Improvements in & relating to method & apparatus for carrying out sub-sea operations lines |
Publications (2)
Publication Number | Publication Date |
---|---|
GB8913797D0 GB8913797D0 (en) | 1989-08-02 |
GB2222215A true GB2222215A (en) | 1990-02-28 |
Family
ID=10638834
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB888814368A Pending GB8814368D0 (en) | 1988-06-16 | 1988-06-16 | Improvements in & relating to method & apparatus for carrying out sub-sea operations lines |
GB8913797A Withdrawn GB2222215A (en) | 1988-06-16 | 1989-06-15 | Method and apparatus for assembling and removing seal members in sub-sea operations on fluid-carrying pipes. |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB888814368A Pending GB8814368D0 (en) | 1988-06-16 | 1988-06-16 | Improvements in & relating to method & apparatus for carrying out sub-sea operations lines |
Country Status (1)
Country | Link |
---|---|
GB (2) | GB8814368D0 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19515237A1 (en) * | 1995-04-29 | 1996-10-31 | Krohne Messtechnik Kg | Adjustment device |
DE10108894C1 (en) * | 2001-02-23 | 2002-08-08 | Waterson Chen | Position recovery puller suitable for use in a pipe joint coupling two tubular members |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2195970A (en) * | 1986-09-29 | 1988-04-20 | Total Petroles | Apparatus for use in installing a piece of equipment horizontally on a submerged unit and for removing it therefrom |
-
1988
- 1988-06-16 GB GB888814368A patent/GB8814368D0/en active Pending
-
1989
- 1989-06-15 GB GB8913797A patent/GB2222215A/en not_active Withdrawn
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2195970A (en) * | 1986-09-29 | 1988-04-20 | Total Petroles | Apparatus for use in installing a piece of equipment horizontally on a submerged unit and for removing it therefrom |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19515237A1 (en) * | 1995-04-29 | 1996-10-31 | Krohne Messtechnik Kg | Adjustment device |
DE10108894C1 (en) * | 2001-02-23 | 2002-08-08 | Waterson Chen | Position recovery puller suitable for use in a pipe joint coupling two tubular members |
Also Published As
Publication number | Publication date |
---|---|
GB8913797D0 (en) | 1989-08-02 |
GB8814368D0 (en) | 1988-07-20 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |