US5031697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for troubleshooting gas-lift wells
Assignee: Shell USA Inc
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Filing: 1990-06-22
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Granted: 1991-07-16
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Expires: 2010-06-22
Abstract
Abstract A method is provided for troubleshooting gas-lift wells, to identify whether gas-lift valves on the production tubing are open or closed, without the use of wireline tools. The method may also be used to detect leaks in the production tubing or in the well casing. A quantity of a tracer gas is injected into the lift-gas at the wellhead, and its return in fluid produced from the well is monitored as a function of time. The tracer's return pattern may be correlated with the depth of entry points and volumes of lift-gas entering along the length of the production tubing.
Inventors
- 👤 Scott L. Wellington
- 👤 Jeffrey F. Simmons
- 👤 Edwin A. Richardson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:40
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/10; E21B47/11; E21B43/00; E21B43/12; E21B43/121; E21B43/122; G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; G01M3/22
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
110 words
A method for determining a point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas supplied to the gas-lift well a quantity of an injected fluid, which is at least one of (1) a tracer (2) a tracer generator, in a quantity which is sufficient to be detected in a produced fluid recovered from the well; monitoring a proportion of the tracer in the produced fluid as a function of time; determining the point of entry of the injected fluid into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 2
Independent Claim
110 words
A method for determining a point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas supplied to the gas-lift well a quantity of an injected fluid, which is at least one of (1) a tracer (2) a tracer generator, in a quantity which is sufficient to be detected in a produced fluid recovered from the well; monitoring a proportion of the tracer in the produced fluid as a function of time; determining the point of entry of the injected fluid into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 3
Dependent Claim
36 words
The method of claim 1 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves is open.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves is closed.
Claim 5
Dependent Claim
43 words
The method of claim 1 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves are open, and which of the valves are closed.
Claim 6
Dependent Claim
36 words
The method of claim 1 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to identify a leak in the production tubing.
Claim 7
Dependent Claim
43 words
The method of claim 1 wherein the proportion of the tracer in the produced fluid as a function of time is used to determine the fraction of tracer, and thereby the fraction of lift-gas entering the production tubing at each point of entry.
Claim 8
Independent Claim
117 words
A method for determining a point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into lift-gas supplied to the gas-lift well a quantity of an injected fluid, which is or generates a tracer, the tracer reducing the amount of a component in a produced fluid recovered from the well in a quantity which is sufficient to be detected in the produced fluid; monitoring the reduction in a proportion of the component in the produced fluid as a function of time; determining the point of entry of the injected fluid into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 9
Independent Claim
117 words
A method for determining a point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into lift-gas supplied to the gas-lift well a quantity of an injected fluid, which is or generates a tracer, the tracer reducing the amount of a component in a produced fluid recovered from the well in a quantity which is sufficient to be detected in the produced fluid; monitoring the reduction in a proportion of the component in the produced fluid as a function of time; determining the point of entry of the injected fluid into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 10
Dependent Claim
36 words
The method of claim 7 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves is open.
Claim 11
Dependent Claim
36 words
The method of claim 7 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves is closed.
Claim 12
Dependent Claim
43 words
The method of claim 7 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to determine which of the valves are open, and which of the valves are closed.
Claim 13
Dependent Claim
36 words
The method of claim 7 wherein the point of entry of the lift-gas into the production tubing is correlated with locations of gas-lift valves in the production tubing to identify a leak in the production tubing.
Claim 14
Dependent Claim
46 words
The method of claim 7 wherein the reduction in the proportion of a component in the produced fluid as a function of time is used to determine the fraction of tracer, and thereby the fraction of lift-gas entering the production tubing at each point of entry.
Claim 15
Independent Claim
88 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide which is sufficient to be detected in produced gas recovered from the well; monitoring the concentration of the carbon dioxide in the produced gas as a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 16
Independent Claim
88 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide which is sufficient to be detected in produced gas recovered from the well; monitoring the concentration of the carbon dioxide in the produced gas as a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 17
Independent Claim
96 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide, which generates carbonic acid ions in a quantity that is sufficient to be detected in produced water recovered from the well; monitoring the concentration of the carbonic acid ions in the produced water a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 18
Independent Claim
96 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide, which generates carbonic acid ions in a quantity that is sufficient to be detected in produced water recovered from the well; monitoring the concentration of the carbonic acid ions in the produced water a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 19
Independent Claim
90 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide which is sufficient to be detected in produced gas recovered from the well; monitoring a reduction in the concentration of a component in the produced gas as a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
Claim 20
Independent Claim
90 words
A method for determining the point of entry of a lift-gas into a production tubing in a gas-lift well in a subterranean reservoir comprising: injecting into the lift-gas a quantity of carbon dioxide which is sufficient to be detected in produced gas recovered from the well; monitoring a reduction in the concentration of a component in the produced gas as a function of time; determining the point of entry of the carbon dioxide into the production tubing, thereby determining the point of entry of the lift-gas into the production tubing.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |