WO2010021754A1

WO2010021754A1 - Apparatus for connecting tubular bodies and repairing underwater tubular bodies

Info

Publication number: WO2010021754A1
Application number: PCT/US2009/004795
Authority: WO
Inventors: Charles F. Martin
Original assignee: Lighthouse R & D Enterprises, Inc.
Priority date: 2008-08-20
Filing date: 2009-08-20
Publication date: 2010-02-25

Abstract

Apparatus for connecting first and second tubular members comprising a first collar, a second collar and a spacer therebetween, there being registering throughbores through the first collar, the spacer, and the second collar. The second tubular member is received in the registering throughbores, and engages a stop in the first collar. A locking or slip assembly disposed generally in the second collar is in surrounding relationship to the second tubular member and, when activated, has formations to effect metal-to-metal engagement between a slip member and the second tubular member. A seal assembly disposed generally in the first collar and in surrounding relationship to the second tubular member can be activated by pressurized fluid; e.g., a flowable sealant to force sealing fingers into metal-to-metal sealing engagement with the second tubular member.

Description

APPARATUS FOR CONNECTING TUBULAR BODIES AND REPAIRING UNDERWATER TUBULAR BODIES

FIELD OF THE INVENTION

The present invention relates to an apparatus for connecting tubular bodies together and, more particularly, to such an apparatus which can be used to make an emergency repair of subsea pipelines or other subsea pipe elements.

BACKGROUND OF THE INVENTION

It is often necessary to connect two tubular bodies together either as a new connection of the two tubular bodies or to reconnect two portions of a pre-existing tubular body, e.g., a pipeline which has been damaged, the damaged section having been removed. This is particularly true in the case of subsea pipelines and other subsea tubular structures.

As was demonstrated in connection with Hurricane Katrina, pipelines which are at significant ocean depths can be damaged to the point where flow through the pipeline has to be shut off to avoid environmental and/or safety problems which causes production supply interruptions of crude oil and the like flowing through the pipelines.

Since pipeline repair at great ocean depths is generally time consuming, complicated and expensive, it would be desirable to have a system or apparatus which could rapidly repair the damaged pipeline using an ROV, the repaired section and the associated connections having the same pressure integrity as the original, undamaged pipeline. SUMMARY OF THE INVENTION

In accordance with at least one aspect of the present invention, there is provided an apparatus for connecting first and second tubular members.

In at least a second aspect of the present invention, there is provided an apparatus for use in repairing a damaged section of a pipeline or other subsea tubular member.

In still another aspect of the present invention, there is provided an apparatus for connecting first and second tubular bodies which comprises a coupling apparatus having a pipe locking system to lock a pipe section to the coupling apparatus and a seal assembly which forms a pressure tight metal-to- metal seal between the pipe section and the coupling apparatus.

The coupling apparatus can include a first collar which surrounds a seal assembly used to form a fluid tight seal between the first collar and the pipe section and a second collar in which is received a slip assembly which can be activated to engage and immobilize the tubular member once it is received in the coupling apparatus.

In one embodiment, in operation, once the pipe section is positioned in the coupling assembly, a slip assembly or the like is activated to engage the pipe section and fix it in location in the coupling apparatus. Once the slip assembly has been set, a seal assembly is activated to form a pressure tight metal-to-metal seal between the pipe section and the coupling apparatus.

The coupling apparatus of the present invention can take various forms, the common features being a pipe fixation system or assembly which fixes or locks the pipe section to the coupling apparatus and a seal assembly or system which forms a fluid tight metal-to-metal seal between the pipe section and coupling apparatus.

The coupling apparatus can include a hub or the like which can be secured as by welding to a tubular member.

In still another aspect of the present invention, there is provided a method of repairing a damaged pipe or tubular body by removing the damaged portion of the pipe to provide first and second undamaged pipe end portions, in the first undamaged pipe end portion in one of the coupling apparatuses over the first undamaged pipe end portions, locking the first undamaged pipe end section to the coupling, effecting a seal between the first undamaged pipe end section and the coupling apparatus, positioning in the same or a different form of the coupling apparatus the second undamaged pipe end portion, effecting a seal between the other coupling apparatus and the second undamaged pipe end section and interconnecting a replacement pipe section between the two coupling apparatuses to replace the damaged segment of the pipe which has been removed.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a side elevational view of a damaged pipeline;

Fig. 2 is a view showing the damaged section of the pipeline of Fig. 1 removed leaving two unconnected portions of the pipeline; Fig. 3 shows the coupling apparatus of the present invention and a spanning tubular section between the two tubular portions of the pipe section shown in Fig. 2;

Fig. 4 is a side elevational view one embodiment of the coupling assembly of the present invention having been activated to couple one of the tubular sections to a spanner tubular member;

Fig. 5 is a view similar to Fig. 4 but showing the coupling apparatus prior to being activated;

Fig. 6 is a side elevational view, partly in section, of another embodiment of the coupling apparatus; Fig. 7 is a side, elevational view, partly in section of another embodiment of the coupling apparatus;

Fig. 8 is a side, elevational view, partly in section of the embodiment of Fig. 7 after being activated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to Fig. 1 , there is shown a pipeline P having a damaged section D leaving an undamaged first pipe section 10 and a second undamaged pipe section 12 on opposite sides of the damaged section D. Fig. 2 shows the pipeline P with the damaged section D removed.

Fig. 3 shows a repair of the pipeline P using a first coupling apparatus C_A connected to pipe section 10 and a second coupling apparatus C_B connected to pipe section 12 and a flex line 14 connected between coupling apparatuses CA and C_B thereby effectively creating a pipeline Pi in which pipe sections 10 and 12 are spanned by tubular flex section 14.

Referring now to Fig. 4, one embodiment Ci of the coupling apparatus is shown with pipe section 12 received therein. The coupling apparatus Ci comprises a first collar 16 and a second, spaced collar 18, in surrounding relationship to pipe section 12. First collar 16 has a hub 20 with a bore 22 which preferably has an ID approximately the same as the OD of pipe section 12. Hub 20 also has a first counterbore 24 forming a shoulder 26, the end 28 of pipe member 12 being received in counterbore 24 adjacent and/or abutting shoulder 26. It will be appreciated that as opposed to using a counterbore to provide a shoulder or stop, other stop formations can be employed. Hub 20 has a second counterbore 30. Extending from counterbore 30 is an annular, axially extending groove 32, groove 32 being in communication with an exhaust line 34. Received in counterbore 30 is a generally L shaped (in cross section) annular flange or diaphragm shown generally as 36, flange 36 having an annular, axially extending leg 38, a portion of which can be received in groove 32 and an annular, radially inwardly extending leg 40.

Counterbore 30 cooperates with spacer 60 to form an annularly extending, radially inwardly opening recess 44. As seen, diaphragm 36 is positioned in a pocket 41 formed by counterbore 30, axially extending portion 62A of spacer 60 and rib portion 62 of spacer 60.

Received in recess 44 is a seal assembly shown generally as 46, seal assembly 46 comprising a series of annular, radially inwardly extending, fingers 48, fingers 48 being provided with knife edges 50. Fingers 48 are separated by annular elastomeric or polymeric spacers 52, fingers 48 being attached to an annular base 54, base 54 having an OD substantially the same as the ID of leg 38. A spacer 60 through which is received pipe section 12, has an annular, radially outwardly extending rib 62.

Second collar 18 also has an annular, radially outwardly extending flange portion 64, flange portions 64 and 35 of collars 18 and 16, respectively, and rib 62, having registering bores for receipt of bolts 66 threadedly received in the threaded bores in flange 35. As seen, rib 62 is compressed between flange portions 35 and 64 when bolts 66 are tightened. Second collar 18 has a throughbore 70 in which is received a slip assembly shown generally as 72. A leg 6OA of spacer 60 cooperates with second collar 18 to form an axially extending, annular pocket 79. Slip assembly 72 comprises an annular, radially outermost slip member 80 and an annular, radially innermost slip member 82, a portion of slip member 80 being received in pocket 79. Slip member 80 has a tapered surface 84 which engages a complimentary tapered surface 86 of slip member 82. Basically, when activated, slip members 80 and 82 have engaged, frustoconical camming surfaces.

Slip member 80 has a series of circumferentially spaced, radially outwardly opening recesses 88 having radially innermost frustoconical bottom surfaces 90 in which are received slip locks 92, also frustoconically shaped to engage and be complimentary to surfaces 90, a spring 94 being received in each of recesses 88 to urge the frustoconical surfaces of slip lock 92 and surface 90 into engagement. This assembly ensures that slip member 80, when set, will remain locked in place.

The radially inner surface 96 of slip member 82 is provided with a series of annular serrations or teeth 98 or such formations for a purpose hereinafter described. An end cap 100 is secured to collar 18 by a series of bolts 102 circumferentially spaced around cap 100.

In the embodiment shown in Figs. 4 and 5, the hub 20 of coupling assembly C₂ has been attached by welding apparatus Ci to a nipple 150 on one end of flex line 14. In the embodiment shown in Fig. 4, it can be seen that the knife edges 50 of fingers 48 are not engaged with the outer surface 152 of pipe

12. Further, teeth 98 of slip assembly 92 have not been engaged with the outer surface of pipe 12. Reference is now made to Fig. 5 to show the operation of the coupling assembly C₂. Rib 62 has a first passageway 154 which is in open communication with pocket 44. Rib 62 has a second port or passageway 156 which is in open communication with annular pocket 79. A hydraulic pressure line 160 provided with a valve 152 is connected to a pressurized source of hydraulic fluid (not shown). Upon opening valve 162, pressurized fluid flows through line 160 into passageway 156 and into pocket 79 where it forces slip member 80 in the direction of arrow A, i.e., away from rib 62, camming surfaces 84 and 86 together. As slip member 80 continues to move in the direction of arrow A, formations 98 are forced into biting engagement with the ID of pipe 12 thereby securing coupling C₂ to pipe 12. To prevent any slippage of slip member 80, slip locks 92 have also been cammed against the surfaces 90 and are held in that position by springs 94. Once the slip assembly 72 has been set thereby preventing any axial or rotational movement of pipe 12 relative to coupling assembly C₂, seal assembly 46 can then be activated.

To this end, a line 164 is connected to passageway 154 and port 166 of a container 168 having a first chamber 170 and a second chamber 172 divided by rib 174 having a bore 176 being adapted to sealingly engage a sliding piston rod 178 attached to a first piston head 180 and a second piston head 182. Received in chamber 170 is a flowable elastomer or sealant 184 which can be any number of materials such as polyurethane or other polymeric substances. Preferably, sealant 184 is of the type which essentially solidifies whereby forming a solid, substantially incompressible material. It will be understood that prior to being activated, piston head 180 would be moved adjacent rib 174 and flowable sealant 184 injected into chamber 170 through valve 165.

Chamber 172 is formed between piston head 182 and the end 190 of cylindrical container 168. Chamber 172 is in turn connected via port 189 in end wall 190, line 192 and valve 194 to a high pressure hydraulic source. Upon opening the valve 194, pressurized fluid forces piston head 182 in the direction of arrow B which in turn forces piston head 180 towards port 166 forcing sealant 184 out of port 166 through line 164, valve 165 into passageway 154 and pocket 44 and into engagement with leg 40 of diaphragm 36 forcing diaphragm 36 towards wall 42 of pocket 44, leg 38 of diaphragm 46 being forced into annular groove 32. As diaphragm 36 is forced towards wall 42, the fingers 48 are moved from the inclined or canted position shown in Fig. 4 to the generally vertical position shown in Fig. 5 such that knife edges 50 are forced into biting engagement with the OD 152 of pipe 12 thereby forming a permanent metal-to-metal seal between coupling assembly Ci and pipe 12. As seal 46 is moved into engagement, any air/water trapped in pocket 44 is exhausted through vent 34.

It will be noted and although not described above, that coupling C₂ is provided with various O-rings or seals around the various components, as shown, to ensure necessary fluid-tight sealing when necessary. Referring now to Fig. 6 there is shown another embodiment of the present invention. Coupling assembly C₂ comprises a first collar shown generally as 200 having a hub 201 with a bore 202, a counterbore 204 and an annular flange 206 provided with bolt holes 208 for receipt of threaded studs 210 having a first threaded end 212 and a second threaded end 214, threaded end 214 being engaged by a nut 260. It will be understood that studs 210 are disposed in a circumferential pattern around collar 200.

A first spacer member 220 is positioned between first collar 200 and a second spacer member 222. Spacer member 220 has a series of bores 21 , which are in register with bores 208 in collar 200.

A second spacer member 222 also has a series of bores 224 through which studs 210 extend as in the case of flange 206 and spacer 220. A second collar 226 is disposed distal collar 200, collar 200, first spacer member 220, second spacer member 222 and collar 226 being secured together by a series of threaded studs 210 and associated nuts 216, the threaded ends 212 of studs 210 being received in threaded bores in collar 226. Flange 206 of collar 200 has an annular, axially extending recess 230 formed in the face 232 of flange 206 which abuts spacer member 220. Collar 200 and spacer members 220 and 222 cooperate to form an annularly extending, radially inwardly opening recess 240 in which is received an L-shaped diaphragm 242, diaphragm 242 having an annular, radially inwardly extending leg 244 and an annular, axially extending leg 246. Nested in recess 240 on leg 246 of diaphragm 242 is a seal assembly shown generally as 248, seal assembly 248 comprising a series of annular, radially inwardly extending fingers 250 having knife edges 252, fingers 250 being separated by elastomeric spacers 254. As seen, fingers 252 extend from an annular base 255. Spacer member 222 is provided with a first set of circumferentially spaced blind bores 256 facing leg 244 of diaphragm 242 in each of which is positioned a piston 258. Connected to each of bores 256 but not shown is an annular groove

(not shown), the groove being connected to a source of pressurized fluid (not shown) by a passageway (not shown).

Also formed in spacer member 222 is a second set of blind bore 260, bores 260 being spaced circumferentially around collar 222. Disposed in each of blind bores 260 is a piston 262, blind bores 260 being connected by an annular groove (not shown) and a passageway (not shown) to a source of pressurized fluid (not shown). Disposed in collar 226 is a slip assembly shown generally as 280 comprising annular inner and outer slip members 282 and 284. As seen, bores 260 face slip member 284. Innermost surface of slip member 282 is provided with a series of annular teeth, serrations 286 or other formations in surrounding relationship to the OD of pipe 288. There is an end cap 290 secured to collar 226 by a series of circumferentially spaced bolts 292.

In operation and when pipe 288 is positioned in coupling opposite C₂, the slip assembly 280 is first set by introducing pressurized fluid into the chambers in bores 260 forcing pistons 262 in the direction of arrow C and camming slip member 284 into engagement with slip member 282 forcing teeth 286 to bite into the outer surface of pipe 288. This effectively locks pipe 288 into position in counterbore 205 of collar 200. Once the slip assembly 280 is set, hydraulic pressure is then introduced into chambers 256 to force pistons 258 in the direction of arrow D which forces diaphragm 242 in the direction of arrow D, leg 246 moving into annular recess 230 thereby forcing annular fingers 250 to move to a substantially vertical position relative to the canted position shown in Fig. 6 thereby forcing the knife edges 252 into biting engagement with the outer surface of pipe 288. Turning now to Figs. 7 and 8 there is shown another embodiment of the present invention. Referring first to Fig. 7, coupling assembly C₃ is provided with a first collar 300 having a hub 301 , a bore 302 therethrough and a counterbore 304. Collar 300 has a second counterbore 306 and an annular flange 308 provided with bore holes 310 through which bolts 312 extend to connect first collar 300 to a second collar 314.

Second collar 314 has an annular, radially outwardly extending flange 316, collars 314 and 300 cooperating to form an annularly extending, radially inwardly opening recess 318. A sleeve portion 315 extends axially from collar 314.

A third collar 320 having a flange portion 321 is interconnected to collars

300 and 314 by means of bolts 312. An end cap 322 is secured to the end of collar 320 by a series of bolts 324 received in threaded bores in collar 320 on the end face thereof. A slip assembly shown generally as 326 comprises annular, inner slip member 328 and annular, outer slip member 330, inner slip member 328 being provided with a series of annularly extending teeth or serrations 332. As seen in Fig. 7, teeth 332 are not in engagement with the OD of pipe 334. As can also be seen, the end of pipe 334 is received in counterbore 304 of collar 300. Received in recess 318 is a seal assembly shown generally as 334, seal assembly 334 comprising an annular ring-like member 336 which has first and second end walls 338 and 340 which are annularly extending and axially spaced from one another. End walls 338 and 340 are connected by an annular base 342 which together with the end members 338 and 340 form an annularly extending, radially outwardly opening chamber 344. Extending radially inwardly from base 342 are a plurality of sealing fingers 346, fingers 346 being axially spaced along base 342.

Chamber 344 is connected via a passageway 350 to a source of pressurized sealant (not shown) but described above for a purpose hereafter described, passageway 350 being formed in collar 314.

Also formed in collar 314 is a second passageway 352, passageway 352 communicating with an annular space 354 formed by cooperating surface of collar 314, collar 320 and outer slip member 330. Passageway 352 is in turn connected to a source of pressurized fluid (not shown).

Fig. 8 shows the coupling C₃ connected to pipe 334. To this end, pressurized fluid is introduced through passageway 352 and into annular space 354 which forces outer slip member 330 in the direction of arrow E forcing the complimentary, frustoconical surfaces of slip members 330 and 332 to tightly engage camming radially innermost slip member 328 radially inwardly. This camming action, as seen in Fig. 8, forces teeth 332 to bite into the OD of pipe 334. Once the slip assembly has been set, thereby locking pipe 334 in position in coupling C₃, a flowable, pressurized sealant is introduced to passageway 350 into into chamber 344. The sealant 360 collapses base plate 346 radially inwardly forcing seal fingers 346 into metal-to-metal sealing engagement with the OD of pipe 334. With passageway 350 plugged, sealant 360 cannot escape from chamber 344 and accordingly seal fingers 346 are kept in the sealing, "biting" configuration shown on Fig. 8.

It will be understood that while not specifically described but as shown in the drawings, suitable O-rings and other seals are utilized where necessary to ensure fluid-tight sealing between the various components of all of the coupling assemblies. While the invention has been described with reference to repairing a damaged underwater pipeline, it will be understood that the invention is not so limited and can be employed to connect any two tubular bodies together, be they underwater or not. However, the coupling apparatus of the present invention finds particular application in the repair of underwater pipelines since it can be manipulated by means of an ROV and therefore is useful at great depths.

Claims

Claim 1 : An apparatus for connecting first and second tubular members comprising: a first collar comprising: a hub portion, said hub portion having a first counterbore, said first collar further comprising an annular, radially outwardly extending first flange portion, said first collar being adapted to be connected to a first tubular member, said first collar having a throughbore therethrough; a second collar, comprising: an annular, radially outwardly extending second flange portion and having a throughbore therethrough; a spacer assembly disposed between said first and second collars and having a throughbore therethrough, said spacer assembly and said first collar cooperating to form an annular, radially inwardly facing recess; a slip assembly disposed at least partially in said second collar, said slip assembly comprising annular, radially innermost and radilly outermost slip members, said innermost slip member having at least one radially inwardly extending formation, said outermost slip member being movable axially relative to said innermost slip member; a seal assembly disposed in said radially outwardly facing recess, said seal assembly comprising a sealing member having an annular base and at least one annular, radially inwardly extending finger connected to said base, said finger being movable from a first position wherein said finger has a first radially extending dimension to a second position wherein said finger has a second, greater radially extending dimension; and an annular diaphragm disposed in said recess and being axially movable against said seal member to force said at least one finger into said second position.

Claim 2: An apparatus of Claim 1 , wherein said said spacer assembly comprises a T-shaped member; comprising a radially outwardly extending annular third flange portion, a first axially extending leg and a second axially extending leg, said first collar has a first counterbore and said annular, radially inwardly facing recess is at least partially formed by said first counterbore.

Claim 3: The apparatus of Claim 2, wherein said diaphragm is L- shaped when viewed in cross-section and has an annular, inwardly extending leg portion and an annular axially extending leg portion, said diaphragm being received in a pocket formed by said T-shaped member and said first counterbore.

Claim 4: The apparatus of Claim 1 , wherein there are a plurality of said fingers.

Claim 5: The apparatus of Claim 3, further comprising a passageway for the introduction of said sealant between said third flange portion and said radially inwardly extending leg of said diaphragm, whereby said pressurized sealant can be forced between said radially extending leg of said T-shaped member and said radially extending leg of said diaphragm to move said finger from said first position to said second position. Claim 6: The apparatus of Claim 4, wherein said fingers are separated by annular, polymer spacers.

Claim 7: The apparatus of Claim 4, wherein said fingers have radially innermost knife edges. Claim 8: The apparatus of Claim 2, wherein said second axially extending leg of said spacer and said third collar cooperate to form an annular, axially extending slip recess.

Claim 9: The apparatus of Claim 8, wherein said radially outermost slip member is partially received in said slip recess. Claim 10: The apparatus of Claim 9, wherein there is a passageway in open communication with said slip recess whereby pressurized fluid can be introduced to effect said axial movement of said outermost slip member.

Claim 11 : The apparatus of Claim 1 , wherein said innermost slip member has a plurality of annular, radially inwardly extending formations. Claim 12: The apparatus of Claim 10, wherein there is at least one locking assembly carried by said outermost slip member, said locking assembly being operative to prevent relative axial movement of said innermost and outermost slip members once said pressurized fluid has moved said outermost slip member axially. Claim 13: The apparatus of Claim 12, wherein said locking assembly comprises a plurality of second slip assemblies.

Claim 14: The apparatus of Claim 13, wherein said second slip assemblies include a spring. Claim 15: The apparatus of Claim 2, wherein said first flange portion, said third flange portion and said second flange portion have registering bores for receipt of respective connection assemblies.

Claim 16: The apparatus of Claim 1 , wherein said spacer assembly comprises first and second spacing members, said first spacing member being adjacent said first collar, said second spacing member being adjacent said second collar.

Claim 17: The apparatus of Claim 16, wherein said annular, radially inwardly facing recess is formed by said first collar, said first spacer member and said second spacer member.

Claim 18: The apparatus of Claim 16, wherein there is at least one, first blind bore opening in the direction of said first spacer, and at least one, second blind bore opening in the direction of said second collar, there being a first piston disposal in said first blind bore and a second piston disposal in said second blind bore.

Claim 19: The apparatus of Claim 18, wherein said second pistons can be hydraulically urged into engagement with said outermost slip member to effect said axial movement of said outermost slip member.

Claim 20: The apparatus of Claim 18, wherein said diaphragm is L- shaped and has an annular radially inwardly extending leg portion and an annular axially extending leg portion, said diaphragm being received in said annular, radially inwardly facing recess. Claim 21 : The apparatus of Claim 20, wherein said first piston can be hydraulically urged into engagement with said annular, radially extending leg portion of said diaphragm.

Claim 22: The apparatus of Claim 18, wherein there is a plurality of said first and second blind bores containing a plurality of first and second pistons, respectively.

Claim 23: An apparatus for connecting first and second tubular members comprising: a first collar having a hub portion and a first annular, radially outwardly extending flange portion, said first collar having a throughbore therethrough; a second collar having a second annular, radially outwardly extending flange portion, said first and second collars cooperating to form an annularly extending, radially inwardly opening recess, said second collar having a throughbore therethrough; a third collar comprising a third annular, radially outwardly extending flange portion, said second collar being positioned between said first and third collars, said third collar having a throughbore therethrough; a slip assembly comprising an annular, radially outermost slip member and an annular, radially innermost slip member, said innermost slip member having at least one radially inwardly extending formation, said outermost slip member being axially movable relative to said innermost slip member; and a seal assembly disposed in said radially inwardly opening recess, said seal assembly comprising a base and at least one annular, radially inwardly extending finger connected to said base, said finger being movable from a first position wherein said finger has a first, radially extending dimension to a second position wherein said finger has a second, greater radially extending dimension, said base defining an annular, radially outwardly opening chamber for receiving a pressurized, flowable sealant.

Claim 24: The apparatus of Claim 23, wherein said second collar and said third collar cooperate to form the annular, axially extending recess.

Claim 25: The apparatus of Claim 24, wherein a portion of said outermost slip member is received in said axially extending recess. Claim 26: The apparatus of Claim 25, wherein a pressurized fluid can be introduced into said axial recess to effect said axial movement of said outermost slip member.

Claim 27: The apparatus of Claim 23, wherein there is a passageway for introducing said pressurized, flowable sealant into said annular, radially outwardly opening chamber.

Claim 28: The apparatus of Claim 23, wherein there is plurality of said fingers and said fingers are urged into said second position by pressurized flowable sealant received in said annular chamber.

Claim 29: The apparatus of Claim 23, wherein said first, second and third flange portions are provided with registering bores and there are respective connection assemblies in said registering bores.

Claim 30: A method of repairing a damaged pipeline comprising: removing a damaged section of the pipeline to produce first and second undamaged pipe end portions; positioning said first undamaged pipe end portion in a first coupling apparatus according to any one of Claims 1 or 23; locking said first coupling apparatus to said first undamaged pipe end portion; effecting metal-to-metal sealing between said first coupling apparatus and said first undamaged pipe end portion; positioning said second undamaged pipe end portion in a second coupling assembly according to any one of Claims 1 or 23; locking said second coupling assembly to said second undamaged pipe end portion; effecting metal-to-metal sealing between said second coupling apparatus and said second undamaged pipe end portion; and interconnecting a replacement pipe section to said first and second coupling apparatuses.