Patent US4738812A successfully refreshed from Google Patents.
US4738812A
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Method of forming an electrode structure
Assignee: Baker Hughes Oilfield Operations LLC
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Filing: 1982-11-12
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Granted: 1988-04-19
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Expires: 2002-11-12
Abstract
Abstract An array of electrodes is presented for accurate and improved measurement of borehole resistivity. Electrode structures and methods of formation thereof are also presented.
Inventors
- 👤 Jean C. Raynal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:52
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/003; E21B47/00; E21B47/01; E21B7/00; E21B7/04; E21B7/06; G; G01; G01V; G01V3/00; G01V3/18; G01V3/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
97 words
A method of formation of an array of electrodes on a segment of a drill string, including the steps of: positioning electrode support means along an axial length of a drill string segment; positioning a plurality of electrodes on said support means at axially spaced locations along said length of drill string segment and spaced from the outer surface of said length of drill string segment; and molding an insulating material to said axial length of drill string segment to produce an array of electrodes embedded in a length of insulating material on said drill string segment.
Claim 2
Independent Claim
97 words
A method of formation of an array of electrodes on a segment of a drill string, including the steps of: positioning electrode support means along an axial length of a drill string segment; positioning a plurality of electrodes on said support means at axially spaced locations along said length of drill string segment and spaced from the outer surface of said length of drill string segment; and molding an insulating material to said axial length of drill string segment to produce an array of electrodes embedded in a length of insulating material on said drill string segment.
Claim 3
Dependent Claim
46 words
The method of formation of an array of electrodes on a segment of a drill string as in claim 1 wherein: said axial length of drill string segment is recessed, and said support means, said electrodes and said insulating material are located in said recessed length.
Claim 4
Dependent Claim
67 words
The method of formation of an array of electrodes on a segment of a drill string as in claim 2 wherein said step of molding includes: positioning mold structure about said length of drill string segment to define a mold cavity; introducing a molding material into said mold cavity, and curing the molding material to form said array of electrodes embedded in a length of molding material.
Claim 5
Dependent Claim
73 words
The method of formation of an array of electrodes on a segment of a drill string as in claim 3 wherein: said step of positioning support means includes locating a plurality of support elements along said recessed length of the drill string segment in an array which permits flow of insulating material along the recessed length; and said step of positioning electrodes includes positioning ring electrode elements on each of said support elements.
Claim 6
Dependent Claim
52 words
The method of formation of an array of electrodes on a segment of a drill string as in claim 2, including: positioning compensating means in said recess to divide said recess into at least two segments to compensate for differential expansion or contraction between said drill string segment and said insulating material.
Claim 7
Dependent Claim
88 words
The method of formation of an array of electrodes on a segment of a drill string as in claim 5 wherein: said compensating means divides said recessed length into a plurality of recessed segments; and wherein the step of molding includes: positioning mold structure about the length of each recessed segment to define a plurality of mold cavities; introducing a molding material into each mold cavity; and curing the molding material to form said array of electrodes embedded in a length of molding material with expansion compensating means.
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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) | 1991-04-19 | 1991-10-19 | 1992-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-19 | 1995-10-19 | 1996-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-19 | 1999-10-19 | 2000-04-19 | $7700.00 | Window Closed / Lapsed |