Patent US6144505A successfully refreshed from Google Patents.
Patent US5537190A successfully refreshed from Google Patents.
Patent US5125427A successfully refreshed from Google Patents.
US5125427A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Freeze-thaw method for temporarily plugging process flowline
Assignee: ConocoPhillips Co
•
Filing: 1991-04-02
•
Granted: 1992-06-30
•
Expires: 2011-04-02
Abstract
Abstract Temporary plugs are formed in process flowlines by injecting into the flowlines a plugging material having a freezing point only slightly below the ambient temperature. The plugging material is frozen in place, and a servicing operation is conducted on the flowline. The plugging material is then allowed to thaw or is thawed by applied heat. Linear primary alcohols and normal paraffinic hydrocarbons are preferred plugging materials.
Inventors
- 👤 Lisa A. Cantu
- 👤 Allen R. Petree
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:12
CPC Classifications
F; F16; F16K; F16K13/00; F16K13/08; F16K13/10; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0391; Y10T137/6416
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
A method for temporarily plugging a process flowline, the method comprising: (a) injecting a liquified plugging agent selected from the group consisting of linear primary alcohols and normal paraffinic hydrocarbons, said agent having a freezing point below the ambient temperature around said flowline, into said flowline in direct contact with the interior surface of said flowline at a location to be plugged; (b) removing sufficient heat from said plugging agent to freeze said plugging agent in said flowline; (c) performing a service operation on said flowline; and (d) thawing said plugging agent and returning aid flowline to service.
Claim 2
Independent Claim
98 words
A method for temporarily plugging a process flowline, the method comprising: (a) injecting a liquified plugging agent selected from the group consisting of linear primary alcohols and normal paraffinic hydrocarbons, said agent having a freezing point below the ambient temperature around said flowline, into said flowline in direct contact with the interior surface of said flowline at a location to be plugged; (b) removing sufficient heat from said plugging agent to freeze said plugging agent in said flowline; (c) performing a service operation on said flowline; and (d) thawing said plugging agent and returning aid flowline to service.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein said plugging agent is undecyl alcohol.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said plugging agent is heptadecane.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said ambient temperature is at least 20° C.
Claim 6
Dependent Claim
26 words
The method of claim 1 wherein said plugging agent has a freezing point of from 10° to 15° C. below said ambient temperature around said flowline.
Claim 7
Dependent Claim
28 words
The method of claim 1 wherein said flowline is one of a plurality of well production flowlines extending from a plurality of wells to a common processing unit.
Claim 8
Dependent Claim
22 words
The method of claim 1 wherein said flowline is a well production flowline extending to a treating facility on an offshore platform.
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) | 1995-06-30 | 1995-12-30 | 1996-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-30 | 1999-12-30 | 2000-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-30 | 2003-12-30 | 2004-06-30 | $7700.00 | Window Closed / Lapsed |