US3815671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipeline forced air convective heat transfer system
Assignee: Individual
•
Filing: 1972-12-05
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Granted: 1974-06-11
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Expires: 1992-12-05
Abstract
Abstract A system using air for removing heat from a pipeline laid in permafrost areas has an insulated duct-like member encircling an elevated section of the pipeline with an annular air flow space therebetween and at least one top outlet and one bottom inlet thereto. The outlet and the inlet are spaced apart along the longitudinal axis of the pipeline. An air deflector is positioned to deflect air into the inlet thereby increasing natural convective air forces arising inside the convective heat transfer system. The insulation standoff distance, the ratio of the inletto-annular space areas of flow, and the spacing between inlet and outlet ports are set for maximum advantage. Additional advantage is obtained by using an elongated outlet stack.
Inventors
- 👤 J Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:49
CPC Classifications
F; F17; F17D; F17D1/00; F16; F16L; F16L53/00; F16L53/70
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
205 words
A convective heat transfer system for an oil pipeline which is partially buried in permafrost comprising a section of an oil pipeline elevated above the ground and surrounded by insulating material in a manner such that there is annular air-conductive space surrounding said section of said pipeline between said insulation material and said pipeline, an outlet to said annular space located on the top side of said pipeline and adapted to allow air to flow from said annular space, an inlet to said annular space located on the bottom side of said pipeline and adapted to allow atmospheric air to flow into said annular space, said inlet and said outlet being spaced apart one from the other along the longitudinal axis of said pipeline, and an air deflecting means positioned and adapted to deflect atmospheric air moving past said section of said pipeline into said inlet thereby increasing natural convective air forces arising when oil flows through said section of said pipeline and atmospheric air colder than said oil flows into said inlet through said annular space and out said outlet and is heated by heat transfer from said oil through the walls of said pipeline to the cooler air flowing in said annular space.
Claim 2
Dependent Claim
205 words
A convective heat transfer system for an oil pipeline which is partially buried in permafrost comprising a section of an oil pipeline elevated above the ground and surrounded by insulating material in a manner such that there is annular air-conductive space surrounding said section of said pipeline between said insulation material and said pipeline, an outlet to said annular space located on the top side of said pipeline and adapted to allow air to flow from said annular space, an inlet to said annular space located on the bottom side of said pipeline and adapted to allow atmospheric air to flow into said annular space, said inlet and said outlet being spaced apart one from the other along the longitudinal axis of said pipeline, and an air deflecting means positioned and adapted to deflect atmospheric air moving past said section of said pipeline into said inlet thereby increasing natural convective air forces arising when oil flows through said section of said pipeline and atmospheric air colder than said oil flows into said inlet through said annular space and out said outlet and is heated by heat transfer from said oil through the walls of said pipeline to the cooler air flowing in said annular space.
Claim 3
Dependent Claim
30 words
The system of claim 1 wherein the ratio of the area of flow of the inlet to the area of flow of the annular space is between 1 and 4.
Claim 4
Dependent Claim
25 words
The system of claim 2 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 5
Dependent Claim
34 words
The system of claim 2 wherein the outlet is comprised of an elongated flow passage extending upward approximately perpendicularly to the longitudinal axis of the pipeline for a distance between 1 and 6 feet.
Claim 6
Dependent Claim
25 words
The system of claim 4 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 7
Dependent Claim
34 words
The system of claim 1 wherein the outlet is comprised of an elongated flow passage extending upward approximately perpendicularly to the longitudinal axis of the pipeline for a distance between 1 and 6 feet.
Claim 8
Dependent Claim
25 words
The system of claim 6 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 9
Dependent Claim
25 words
The system of claim 1 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 10
Dependent Claim
23 words
The system of claim 1 wherein the longitudinal spacing between the inlet port and the outlet port is between 20 and 100 feet.
Claim 11
Dependent Claim
25 words
The system of claim 9 wherein the insulation matErial is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 12
Dependent Claim
34 words
The system of claim 9 wherein the outlet is comprised of an elongated flow passage extending upward approximately perpendicularly to the longitudinal axis of the pipeline for a distance between 1 and 6 feet.
Claim 13
Dependent Claim
25 words
The system of claim 11 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 14
Dependent Claim
30 words
The system of claim 9 wherein the ratio of the area of flow of the inlet to the area of flow of the annular space is between 1 and 4.
Claim 15
Dependent Claim
25 words
The system of claim 13 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
Claim 16
Dependent Claim
34 words
The system of claim 13 wherein the outlet is comprises of an elongated flow passage extending upward approximately perpendicularly to the longitudinal axis of the pipeline for a distance betwen 1 and 6 feet.
Claim 17
Dependent Claim
25 words
The system of claim 15 wherein the insulation material is separated from the pipeline by an average standoff distance of between 3 and 6 inches.
References Cited (Backward Citations)
US2541162A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |