US3818323A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature-stabilized logging sonde
Assignee: Texaco Inc
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Filing: 1973-02-09
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Granted: 1974-06-18
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Expires: 1993-02-09
Abstract
Abstract A logging sonde for deep-well measurement. It is for determining electromagnetic properties of formations adjacent to the walls of the borehole. Such properties include magnetic susceptibility and/or resistivity as determined by electromagnetic induction. The sonde structure has a hollow core with transmitter and receiver coils wound thereon. The core contains a circulating fluid, and there is means for establishing and maintaining a constant temperature in order to stabilize the electrical properties of the sonde.
Inventors
- 👤 D Dowling
- 👤 J Boyd
- 👤 J Fuchs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:55
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/26; G01V3/28; E; E21; E21B; E21B47/00; E21B47/01; E21B47/017; E21B47/0175
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
135 words
An improved temperature-stabilized sonde, comprising in combination a hollow core having a transmitter coil and a receiver coil wound thereon, a circulating fluid in said hollow core, means for maintaining the temperature of said fluid constant, a casing for enclosing said core and coils, means for mounting said core and coils axially within said casing, means for introducing said circulating fluid adjacent one end of said core, means for withdrawing said circulating fluid adjacent the other end of said core from said introducing end, thermal barrier means for heat-insulating said core and coils from said casing, said thermal barrier means comprising an enclosure surrounding said core and coils, means for spacing said enclosure from the inside of said casing, and said means for introducing circulating fluid comprising a passage within the walls of said enclosure.
Claim 2
Dependent Claim
135 words
An improved temperature-stabilized sonde, comprising in combination a hollow core having a transmitter coil and a receiver coil wound thereon, a circulating fluid in said hollow core, means for maintaining the temperature of said fluid constant, a casing for enclosing said core and coils, means for mounting said core and coils axially within said casing, means for introducing said circulating fluid adjacent one end of said core, means for withdrawing said circulating fluid adjacent the other end of said core from said introducing end, thermal barrier means for heat-insulating said core and coils from said casing, said thermal barrier means comprising an enclosure surrounding said core and coils, means for spacing said enclosure from the inside of said casing, and said means for introducing circulating fluid comprising a passage within the walls of said enclosure.
Claim 3
Dependent Claim
15 words
A logging sonde according to claim 1, wherein said core and said enclosure are nonmagnetic.
Claim 4
Dependent Claim
25 words
A logging sonde according to claim 2, wherein said temperature is maintained at a level above the anticipated maximum in a well to be logged.
Claim 5
Dependent Claim
13 words
A logging sonde according to claim 3, wherein said circulating fluid is oil.
Claim 6
Dependent Claim
174 words
An improved temperature-stabilized logging sonde, comprising in combination a predetermined length of nonmagnetic mandrel tubing having a transmitter coil and a receiver coil wound thereon, fluid-tight end pieces for closing the interior of said mandrel tubing, thermally conductive oil filling said mandrel tubing, a pump for circulating said oil within said mandrel tubing, an AC electric motor for driving said pump, first nonmagnetic tubing for connecting the discharge of said pump to one end of said mandrel tubing, second nonmagnetic tubing for connecting the suction of said pump to the other end of said mandrel tubing, a nonmagnetic casing for enclosing the elements of said sonde therein, a nonmagnetic thermal barrier tube mounted inside of and spaced from said casing and surrounding said mandrel tubing and coils, an AC electric heater for raising the temperature of said oil adjacent to the inlet to said mandrel tubing, a temperature sensor located in contact with said oil circulating from said mandrel tubing, and AC zero-crossing means for regulating said heater in accordance with said temperature sensor.
Claim 7
Dependent Claim
174 words
An improved temperature-stabilized logging sonde, comprising in combination a predetermined length of nonmagnetic mandrel tubing having a transmitter coil and a receiver coil wound thereon, fluid-tight end pieces for closing the interior of said mandrel tubing, thermally conductive oil filling said mandrel tubing, a pump for circulating said oil within said mandrel tubing, an AC electric motor for driving said pump, first nonmagnetic tubing for connecting the discharge of said pump to one end of said mandrel tubing, second nonmagnetic tubing for connecting the suction of said pump to the other end of said mandrel tubing, a nonmagnetic casing for enclosing the elements of said sonde therein, a nonmagnetic thermal barrier tube mounted inside of and spaced from said casing and surrounding said mandrel tubing and coils, an AC electric heater for raising the temperature of said oil adjacent to the inlet to said mandrel tubing, a temperature sensor located in contact with said oil circulating from said mandrel tubing, and AC zero-crossing means for regulating said heater in accordance with said temperature sensor.
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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) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |