US4803479A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical phase measurement means and method for accurate determination of well logging cable length
Assignee: Chevron USA Inc
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Filing: 1987-10-21
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Granted: 1989-02-07
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Expires: 2007-10-21
Abstract
Abstract A method and apparatus for determining the vertical location of a logging tool in a wellbore is disclosed. An electrical signal is transmitted through a conductor in a well logging cable and a second conductor in the surface. Change in length of the well logging cable is determined by monitoring phase changes in the signals from the first and second conductors.
Inventors
- 👤 Peter Graebner
- 👤 Swan A. Sie
- 👤 Jorg A. Angehrn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:32
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/04; G; G01; G01B; G01B11/00; G01B11/02; G01B11/04; G01B11/043; G01B11/16; G01B11/161
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
114 words
Apparatus for determining the change in length of a well logging cable holding a tool comprising: a sinusoidal electrical signal generating means; a first conductive means of a fixed length; a second conductive means, said second conductive means extending downwardly into a wellbore and rigidly connected to the cable; a third conductive means, said third conductive means extending upwardly from the tool in the wellbore to the surface and operably connected to said second conductive means; and a means for comparing the phase shift of a signal between said first conductive means and said third conductive means. means for calculating the change in length of the well logging cable based on said phase shift.
Claim 2
Dependent Claim
114 words
Apparatus for determining the change in length of a well logging cable holding a tool comprising: a sinusoidal electrical signal generating means; a first conductive means of a fixed length; a second conductive means, said second conductive means extending downwardly into a wellbore and rigidly connected to the cable; a third conductive means, said third conductive means extending upwardly from the tool in the wellbore to the surface and operably connected to said second conductive means; and a means for comparing the phase shift of a signal between said first conductive means and said third conductive means. means for calculating the change in length of the well logging cable based on said phase shift.
Claim 3
Dependent Claim
24 words
Apparatus as recited in claim 1 further comprising a filter means operably connected to said means for comparing the phase shift of a signal.
Claim 4
Dependent Claim
24 words
Apparatus as recited in claim 2 wherein said signal generating means can generate a signal in the range of 100 Mhz and 10 Mhz.
Claim 5
Independent Claim
121 words
A method of determining a change in length of a well logging cable holding a tool comprising the steps of (a) generating a sinusoidal electrical signal; (b) conducting said sinusoidal electrical signal through a first conductive means of a fixed length to produce a second signal; (c) conducting said sinusoidal electrical signal through a second conductive means, said second conductive means extending downwardly into a wellbore and rigidly connected to the cable; (d) returning said signal to the surface of the wellbore from said second conductive means to produce a third signal; (e) comparing a phase shift of the second signal and the third signal; (f) calculating a change in length of the well logging cable based on said phase shift.
Claim 6
Independent Claim
121 words
A method of determining a change in length of a well logging cable holding a tool comprising the steps of (a) generating a sinusoidal electrical signal; (b) conducting said sinusoidal electrical signal through a first conductive means of a fixed length to produce a second signal; (c) conducting said sinusoidal electrical signal through a second conductive means, said second conductive means extending downwardly into a wellbore and rigidly connected to the cable; (d) returning said signal to the surface of the wellbore from said second conductive means to produce a third signal; (e) comparing a phase shift of the second signal and the third signal; (f) calculating a change in length of the well logging cable based on said phase shift.
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) | 1992-02-07 | 1992-08-08 | 1993-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-07 | 1996-08-08 | 1997-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-07 | 2000-08-08 | 2001-02-07 | $7700.00 | Window Closed / Lapsed |