US3788084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of marine pipelines
Assignee: ExxonMobil Upstream Research Co
•
Filing: 1972-06-23
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Granted: 1974-01-29
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Expires: 1992-06-23
Abstract
Abstract A liquid-filled pipeline is recovered from the bottom of a body of water by introducing gas into a submerged end of the line behind a one-way pigging device until a section of the line at least sufficiently long to reach to the surface of the body of water has been substantially voided of liquids and thereafter lifting the end of the pipeline to the water''s surface. The procedure disclosed often reduces substantially the amount of liquid that must be removed from the line to permit lifting of the pipe without danger of buckling.
Inventors
- 👤 J Matthews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:49
CPC Classifications
F; F16; F16L; F16L1/00; F16L1/12; F16L1/16; F16L1/166; E; E21; E21B; E21B23/00; E21B23/08; E21B23/10; F16L55/00; F16L55/10; F16L55/12; F16L55/128; F16L55/1283
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
159 words
A method for recovering a submerged end of a liquid-filled pipeline from the bottom of a body of water which comprises inserting into said submerged end of said pipeline a one-way pigging device adapted to move forward in said pipeline in response to fluid pressure from behind said device and to resist movement in response to fluid pressure from the opposite direction; introducing a gas into said submerged end of said pipeline behind said pigging device under sufficient pressure to move said pigging device forward in said pipeline while preventing the entry of water into said submerged end until said pigging device has traversed a section of said pipeline sufficiently long to extend at least to the surface of said body of water; discontinuing the introduction of said gas; and thereafter lifting said submerged end of said pipeline to the water''s surface, said pigging device preventing the backflow of liquid in said pipeline in response to changes in pressure.
Claim 2
Independent Claim
159 words
A method for recovering a submerged end of a liquid-filled pipeline from the bottom of a body of water which comprises inserting into said submerged end of said pipeline a one-way pigging device adapted to move forward in said pipeline in response to fluid pressure from behind said device and to resist movement in response to fluid pressure from the opposite direction; introducing a gas into said submerged end of said pipeline behind said pigging device under sufficient pressure to move said pigging device forward in said pipeline while preventing the entry of water into said submerged end until said pigging device has traversed a section of said pipeline sufficiently long to extend at least to the surface of said body of water; discontinuing the introduction of said gas; and thereafter lifting said submerged end of said pipeline to the water''s surface, said pigging device preventing the backflow of liquid in said pipeline in response to changes in pressure.
Claim 3
Dependent Claim
24 words
A method as defined by claim 1 including the additional step of withdrawing liquids from said pipeline in advance of said one-way pigging device.
Claim 4
Dependent Claim
28 words
A method as defined by claim 1 wherein said gas is introduced at a pressure in excess of the hydrostatic head exerted by liquid present in said pipeline.
Claim 5
Dependent Claim
16 words
A method as defined by claim 1 wherein said gas is introduced at essentially atmospheric pressure.
Claim 6
Dependent Claim
36 words
A method as defined by claim 1 wherein said liquid is withdrawn by lowering a pump in a pipeline riser to which said pipeline is connected and pumping liquid from said riser to the water''s surface.
Claim 7
Independent Claim
198 words
A method for recovering an end of a submerged liquid-filled pipeline from the bottom of a body of water which comprises inserting into said end of said pipeline a pigging device adapted to move forward through said pipeline in response to differential pressure from behind said device and to resist movement in response to pressure from the opposite direction, installing a fluid-tight closure fitted with a gas inlet line on said end of said pipeline behind said pigging device, injecting a gas through said gas inlet line into said pipeline from a source at the surface of said body of water while discharging liquid from the other end of said pipeline until said pigging device has displaced liquid from a section of said pipeline adjacent said end sufficiently long to extend from said bottom of said body of water along a modified catenary curve to a point above the surface of said body of water, and thereafter lifting said end of said pipeline to the water''s surface under sufficient tension to prevent buckling of the pipeline, said pigging device preventing the backflow of liquid into the gas-filled section of said pipeline in response to changes in pressure therein.
Claim 8
Independent Claim
198 words
A method for recovering an end of a submerged liquid-filled pipeline from the bottom of a body of water which comprises inserting into said end of said pipeline a pigging device adapted to move forward through said pipeline in response to differential pressure from behind said device and to resist movement in response to pressure from the opposite direction, installing a fluid-tight closure fitted with a gas inlet line on said end of said pipeline behind said pigging device, injecting a gas through said gas inlet line into said pipeline from a source at the surface of said body of water while discharging liquid from the other end of said pipeline until said pigging device has displaced liquid from a section of said pipeline adjacent said end sufficiently long to extend from said bottom of said body of water along a modified catenary curve to a point above the surface of said body of water, and thereafter lifting said end of said pipeline to the water''s surface under sufficient tension to prevent buckling of the pipeline, said pigging device preventing the backflow of liquid into the gas-filled section of said pipeline in response to changes in pressure therein.
Claim 9
Dependent Claim
22 words
A method as defined by claim 6 including the step of pumping liquids from said pipeline in advance of said pigging device.
Claim 10
Dependent Claim
12 words
A method as defined by claim 6 wherein said gas is air.
Claim 11
Dependent Claim
22 words
A method as defined by claim 6 wherein said pigging device is inserted in said end of said pipeline by a diver.
Claim 12
Dependent Claim
29 words
A method as defined by clAim 6 wherein said gas inlet line is vented to the atmosphere after said pigging device has moved through said section of said pipeline.
Claim 13
Dependent Claim
120 words
A pipeline pigging device which comprises an outer framework, a sealing element mounted on said outer framework about the periphery thereof for maintaining a seal between said framework and the inner wall of a pipeline, a fluid-tight member supported within said outer framework and longitudinally movable with respect thereto in response to differential pressure, a plurality of wall-engaging members attached to said outer framework for engaging said inner wall of said pipeline and holding said framework in fixed position within said pipeline, and means linking said wall-engaging members and said fluid-tight member for extending said wall-engaging members into contact with the pipeline wall when said movable member moves toward the rear of said outer framework in response to differential pressure.
Claim 14
Dependent Claim
120 words
A pipeline pigging device which comprises an outer framework, a sealing element mounted on said outer framework about the periphery thereof for maintaining a seal between said framework and the inner wall of a pipeline, a fluid-tight member supported within said outer framework and longitudinally movable with respect thereto in response to differential pressure, a plurality of wall-engaging members attached to said outer framework for engaging said inner wall of said pipeline and holding said framework in fixed position within said pipeline, and means linking said wall-engaging members and said fluid-tight member for extending said wall-engaging members into contact with the pipeline wall when said movable member moves toward the rear of said outer framework in response to differential pressure.
Claim 15
Dependent Claim
13 words
Apparatus as defined by claim 11 wherein said fluid-tight member comprises a diaphragm.
Claim 16
Dependent Claim
13 words
Apparatus as defined by claim 11 wherein said fluid-tight member comprises a piston.
Claim 17
Dependent Claim
122 words
A one-way pig for use in pipelining operations which comprises a rigid body structure containing a central opening therein, a sealing element extending about the periphery of said body structure for maintaining a seal between said structure and the inner wall of a pipeline, a longitudinally movable member mounted in said central opening in fluid-tight relationship to said body structure, a plurality of radial arms linked to said body structure for engaging said inner wall of said pipeline and holding said structure in place therein, and means attached to said longitudinally movable member for retracting said radial arms in response to fluid pressure from behind said body structure and for extending said arms in response to fluid pressure in the opposite direction.
Claim 18
Dependent Claim
122 words
A one-way pig for use in pipelining operations which comprises a rigid body structure containing a central opening therein, a sealing element extending about the periphery of said body structure for maintaining a seal between said structure and the inner wall of a pipeline, a longitudinally movable member mounted in said central opening in fluid-tight relationship to said body structure, a plurality of radial arms linked to said body structure for engaging said inner wall of said pipeline and holding said structure in place therein, and means attached to said longitudinally movable member for retracting said radial arms in response to fluid pressure from behind said body structure and for extending said arms in response to fluid pressure in the opposite direction.
Claim 19
Dependent Claim
50 words
A pig as defined by claim 14 wherein said radial arms are linked to said body structure near the outer ends of said arms by pins which extend into slots in said structure and said arms are pivoted near their inner ends to said means attached to said longitudinally-movable member.
Claim 20
Dependent Claim
37 words
A pig as defined by claim 14 wherein said longitudinally-movable member comprises a diaphragm and said means attached to said member comprises a slidable member to which said radial arms are pivotally connected near their inner ends.
Claim 21
Dependent Claim
27 words
A pig as defined by claim 14 wherein the outer ends of said radial arms are provided with teeth for engaging said inner wall of said pipeline.
Claim 22
Dependent Claim
26 words
A pig as defined by claim 14 wherein said body structure includes a cylindrical sleeve and said longitudinally-movable member comprises a piston mounted in said sleeve.
Claim 23
Dependent Claim
17 words
A pig as defined by claim 14 including rollers for supporting said body structure within said pipeline.
Claim 24
Dependent Claim
24 words
A pig as defined by claim 14 wherein said sealing element comprises a resilient ring attached to the outer surface of said body structure.
Claim 25
Dependent Claim
112 words
A pipeline pigging device adapted to move through a pipeline in one direction and resist movement in the opposite direction which comprises a generally cylindrical pig body, a resilient sealing element on the periphery of said body for maintaining a seal between said body and the inner wall of a surrounding pipeline, holding means on said body for engaging said inner wall and preventing movement of said body within said pipeline, and means for disengaging said holding means in response to fluid pressure tending to move said body forward in said pipeline and for actuating said holding means in response to fluid pressure tending to move said body in the opposite direction.
Claim 26
Dependent Claim
112 words
A pipeline pigging device adapted to move through a pipeline in one direction and resist movement in the opposite direction which comprises a generally cylindrical pig body, a resilient sealing element on the periphery of said body for maintaining a seal between said body and the inner wall of a surrounding pipeline, holding means on said body for engaging said inner wall and preventing movement of said body within said pipeline, and means for disengaging said holding means in response to fluid pressure tending to move said body forward in said pipeline and for actuating said holding means in response to fluid pressure tending to move said body in the opposite direction.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |