US3677310A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for connection of an underwater riser to a floating facility
Assignee: SUBSEA EQUIPMENT ASS Ltd
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Filing: 1970-07-09
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Granted: 1972-07-18
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Expires: 1990-07-09
Abstract
Abstract This specification discloses a method and apparatus for connecting a flowline of a well or satellite system which is located at a substantial distance beneath the surface of a body of water. A flowline, which is known as a riser, is provided at a well head or riser manifold. At the upper free end, off the flowline, there is a riser buoy which is releasably attached to a tanker during flowing operations and disconnectable during storms or otherwise violent sea conditions. In the disconnected mode, the riser remains submerged under the ocean surface to avoid excess structural loading. The riser is supported by means of a float to maintain tension within acceptable stress limits throughout a wide range of changes in vertical and some horizontal movements when the riser is disengaged from the tanker.
Inventors
- 👤 Christian D Dobler
- 👤 Herbert J Lilly Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:21
CPC Classifications
B; B63; B63B; B63B22/00; B63B22/02; B63B22/021; B63B22/023
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
192 words
The method for detachably connecting a riser head on a floating facility with a subsea well installation wherein fluid can be transferred therebetween and said riser head can move vertically toward said sea well, said riser head being guided during movement by a flexible guide line passing therethrough, and said installation comprising a riser base and a flexible transfer riser connected thereto, the upper end of which is located at a substantial distance below sea level, and having attached thereto a detachable surface indicator comprising the steps of: providing a means for suspending said flexible riser in a substantially vertical position above said riser base so that the top of the riser is below Sea level; detachably connecting said surface indicator to said suspending means for locating said underwater transfer riser; positioning said floating facility substantially above said transfer riser; attaching said flexible guide line from said floating facility to said transfer riser; lowering said riser head from said floating facility for connection with said transfer riser so that the riser head is guided by said guide line; and, detachably securing said riser head to said transfer riser for fluid flow therethrough.
Claim 2
Independent Claim
192 words
The method for detachably connecting a riser head on a floating facility with a subsea well installation wherein fluid can be transferred therebetween and said riser head can move vertically toward said sea well, said riser head being guided during movement by a flexible guide line passing therethrough, and said installation comprising a riser base and a flexible transfer riser connected thereto, the upper end of which is located at a substantial distance below sea level, and having attached thereto a detachable surface indicator comprising the steps of: providing a means for suspending said flexible riser in a substantially vertical position above said riser base so that the top of the riser is below Sea level; detachably connecting said surface indicator to said suspending means for locating said underwater transfer riser; positioning said floating facility substantially above said transfer riser; attaching said flexible guide line from said floating facility to said transfer riser; lowering said riser head from said floating facility for connection with said transfer riser so that the riser head is guided by said guide line; and, detachably securing said riser head to said transfer riser for fluid flow therethrough.
Claim 3
Dependent Claim
43 words
The method as recited in claim 1 wherein the following additional steps are included: detaching said surface indicator after said guide line has been attached to said transfer riser; and providing a predetermined tension on said guide line before lowering said riser head.
Claim 4
Dependent Claim
22 words
The method as recited in claim 2 wherein an additional step includes: mooring said floating facility prior to lowering said riser head.
Claim 5
Dependent Claim
35 words
A method as recited in claim 2 wherein the following additional steps are included: disconnecting said riser head from said flexible riser; and hoisting the riser head to a predetermined position on said floating facility.
Claim 6
Dependent Claim
29 words
The method as recited in claim 4 wherein an additional stop includes: relaxing said guide line whereby movement of the floating facility will not affect said subsea well installation.
Claim 7
Dependent Claim
179 words
In combination, a riser and a floating storage facility having a vertical opening therethrough: said riser comprising: at least one fluid flow conduit extending from a subocean installation towards the ocean surface and having relative flexibility, a buoyant means disposed at the upper end thereof and submerged under the surface to support said conduit in a substantially vertical position, and a first pair of tethering lines connected to the top of said riser and adapted to be connected to a marker buoy so that said marker buoy is capable of moving with the tides and wave action, and said floating storage facility comprising: a riser head disposed to move vertically through said opening, a gimbal tower mounted on said facility over said opening and disposed to guide said riser head, a second pair of tethering lines engaging the lower end of said riser head in sliding relation therewith and having means on their ends adapted to engage said first pair of lines so that said riser head can be guided when lowered to engage the top of said riser.
Claim 8
Dependent Claim
179 words
In combination, a riser and a floating storage facility having a vertical opening therethrough: said riser comprising: at least one fluid flow conduit extending from a subocean installation towards the ocean surface and having relative flexibility, a buoyant means disposed at the upper end thereof and submerged under the surface to support said conduit in a substantially vertical position, and a first pair of tethering lines connected to the top of said riser and adapted to be connected to a marker buoy so that said marker buoy is capable of moving with the tides and wave action, and said floating storage facility comprising: a riser head disposed to move vertically through said opening, a gimbal tower mounted on said facility over said opening and disposed to guide said riser head, a second pair of tethering lines engaging the lower end of said riser head in sliding relation therewith and having means on their ends adapted to engage said first pair of lines so that said riser head can be guided when lowered to engage the top of said riser.
Claim 9
Dependent Claim
16 words
The combination of claim 6 wherein control means are provided for vertically positioning said riser head.
Claim 10
Dependent Claim
29 words
The combination of claim 7 wherein tensioning means are provided for applying constant tension to said second pair of lines when said control means is lowering said riser head.
Claim 11
Dependent Claim
32 words
The combination of claim 8 wherein said facility further includes a swivel plug rotatably mounted within said vertical opening so that said gimbal tower is mounted on said plug to rotate therewith.
References Cited (Backward Citations)
US3359741A
Cited
US3517110A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |