US4515010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stuck point indicating device with linear sensing means
Assignee: Western Atlas International Inc
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Filing: 1983-03-25
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Granted: 1985-05-07
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Expires: 2003-03-25
Abstract
Abstract A device for determining the stuck point of a drill pipe in a borehole consisting of two relatively movable sections, anchoring means for each section, a sensing means for detecting relative movement of the two sections and producing an inductance representative of the movement. The inductance is transformed into a frequency modulated signal which is transmitted to the surface and converted from a non-linear direct current voltage representation of relative movement to a linear direct current voltage.
Inventors
- 👤 Vincent C. Weido
- 👤 David Grissom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:32
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/26; E; E21; E21B; E21B47/00; E21B47/09; G01B7/16; G01B7/24
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
167 words
A downhole apparatus for determining the point at which a pipe is stuck in a well comprising: an upper body: means for anchoring said upper body to said pipe; a lower body: means for anchoring said lower body to said pipe; means for connecting said upper and lower bodies, said connecting means being adapted to allow relative axial and rotational movement between said upper body and said lower body; inductance means located in each of said upper and lower bodies and adapted to sense relative movement between said upper and lower bodies; oscillator means located in one of said bodies and wherein said inductance means is included in the tank circuit of said oscillator means for generating a frequency modulated signal in relation to changes in said inductance means; first converter means for converting said frequency modulated signal to a non-linear dc voltage; second converter means for generating a substantially linear voltage in relation to said non-linear voltage; and surface instrumentation means for displaying said linear voltage.
Claim 2
Dependent Claim
167 words
A downhole apparatus for determining the point at which a pipe is stuck in a well comprising: an upper body: means for anchoring said upper body to said pipe; a lower body: means for anchoring said lower body to said pipe; means for connecting said upper and lower bodies, said connecting means being adapted to allow relative axial and rotational movement between said upper body and said lower body; inductance means located in each of said upper and lower bodies and adapted to sense relative movement between said upper and lower bodies; oscillator means located in one of said bodies and wherein said inductance means is included in the tank circuit of said oscillator means for generating a frequency modulated signal in relation to changes in said inductance means; first converter means for converting said frequency modulated signal to a non-linear dc voltage; second converter means for generating a substantially linear voltage in relation to said non-linear voltage; and surface instrumentation means for displaying said linear voltage.
Claim 3
Dependent Claim
14 words
The apparatus of claim 1 wherein said upper and lower anchor means are electromagnetic.
Claim 4
Dependent Claim
30 words
The apparatus of claim 2 wherein said inductance means includes a fixed portion connected to one of said bodies and a movable portion connected to the other of said bodies.
Claim 5
Dependent Claim
22 words
The apparatus of claim 3 wherein said inductance means includes a means for biasing said movable portion to contact said fixed portion.
Claim 6
Dependent Claim
14 words
The apparatus of claim 4 wherein said biasing means is a pulsed electromagnetic force.
Claim 7
Dependent Claim
34 words
The apparatus of claim 5 wherein said biasing means includes additionally a means for biasing said movable portion after a short predetermined period of time after said upper and lower anchor means are actuated.
Claim 8
Independent Claim
124 words
A method of determining the point at which a pipe is stuck in a borehole traversing an earth formation comprising: positioning a movement-sensing means in said pipe at two vertically spaced points at the depth to be tested; subjecting said pipe above said sensing means to a change in stress capable of deforming the pipe between said spaced points, said change in stress being indicated by a change in inductance indicative of said deformation; converting said change in inductance into a frequency modulated signal; converting said frequency modulated signal into a substantially linear voltage capable of quantitative display wherein said display is indicative of deformation between said points in response to said change in stress; and, displaying said linear voltage on the earth's surface.
Claim 9
Independent Claim
124 words
A method of determining the point at which a pipe is stuck in a borehole traversing an earth formation comprising: positioning a movement-sensing means in said pipe at two vertically spaced points at the depth to be tested; subjecting said pipe above said sensing means to a change in stress capable of deforming the pipe between said spaced points, said change in stress being indicated by a change in inductance indicative of said deformation; converting said change in inductance into a frequency modulated signal; converting said frequency modulated signal into a substantially linear voltage capable of quantitative display wherein said display is indicative of deformation between said points in response to said change in stress; and, displaying said linear voltage on the earth's surface.
Claim 10
Dependent Claim
12 words
The method of claim 7 wherein said stress is caused by rotation.
Claim 11
Dependent Claim
26 words
The method of claim 7 further including the additional step of electromagnetically anchoring said movement-sensing means to said pipe prior to inducing said change in stress.
Claim 12
Dependent Claim
33 words
The method of claim 9 further including the steps of maximizing the inductance produced by said inductance producing means and delaying the commencement of said maximizing step for a preselected period of time.
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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) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |