US4688966A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduced J tube pull force
Assignee: Shell USA Inc
•
Filing: 1986-05-27
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Granted: 1987-08-25
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Expires: 2006-05-27
Abstract
Abstract A method and apparatus are provided for reducing the force required to move a pipe through a J-tube riser attached to an offshore platform. The J-tube riser is provided with at least one movable section and the movable section is oscillated as the pipe is moved through the J-tube riser, thereby reducing the force required to move the pipe.
Inventors
- 👤 Joe O. Esparza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:07
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/01; E21B43/0107; E21B43/013; E21B43/0135; F; F16; F16L; F16L1/00; F16L1/12; F16L1/14; F16L1/15
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
63 words
A method for reducing the force required to move a pipe through a J-tube attached to an offshore platform, comprising: constructing the J-tube of longitudinally connected sections, at least one of the sections being movable with respect to another section; and oscillating the movable section as the pipe is moved through the J-tube, thereby reducing friction between the movable section and the pipe.
Claim 2
Independent Claim
63 words
A method for reducing the force required to move a pipe through a J-tube attached to an offshore platform, comprising: constructing the J-tube of longitudinally connected sections, at least one of the sections being movable with respect to another section; and oscillating the movable section as the pipe is moved through the J-tube, thereby reducing friction between the movable section and the pipe.
Claim 3
Dependent Claim
16 words
The method of claim 1 including hinging the movable section to another section of the J-tube.
Claim 4
Dependent Claim
19 words
The method of claim 1 including telescoping a joint of the movable section to another section of the J-tube.
Claim 5
Dependent Claim
14 words
The method of claim 1 including oscillating the movable section with an hydraulic jack.
Claim 6
Independent Claim
65 words
An apparatus for reducing the force required to move a pipe through a J-tube attached to an offshore platform, comprising: longitudinally connected sections forming the J-tube, at least one of the sections being movable with respect to another section; and means for oscillating the movable section as the pipe is moved through the J-tube to reduce the friction between the movable section and the pipe.
Claim 7
Independent Claim
65 words
An apparatus for reducing the force required to move a pipe through a J-tube attached to an offshore platform, comprising: longitudinally connected sections forming the J-tube, at least one of the sections being movable with respect to another section; and means for oscillating the movable section as the pipe is moved through the J-tube to reduce the friction between the movable section and the pipe.
Claim 8
Dependent Claim
17 words
The apparatus of claim 5 wherein the movable section is hinged to another section of the J-tube.
Claim 9
Dependent Claim
18 words
The apparatus of claim 5 wherein another section of the J-tube and the movable section have telescoping joints.
Claim 10
Dependent Claim
14 words
The apparatus of claim 5 including a hydraulic jack for oscillating the movable section.
Claim 11
Dependent Claim
17 words
The method of claim 1 including locating the movable section at the lower end of the J-tube.
Claim 12
Dependent Claim
25 words
The method of claim 1 wherein the movable section connects a laterally extending section of the J-tube with an upwardly extending section of the J-tube.
Claim 13
Dependent Claim
18 words
The apparatus of claim 5 wherein the movable section is located at the lower end of the J-tube.
Claim 14
Dependent Claim
25 words
The apparatus of claim 5 wherein the movable section connects a laterally extending section of the J-tube with an upwardly extending section of the J-tube.
References Cited (Backward Citations)
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Cited
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Cited
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Cited
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Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |