US4524433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed sonic logging using multiple transducers
Assignee: BP Corp North America Inc
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Filing: 1983-08-18
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Granted: 1985-06-18
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Expires: 2003-08-18
Abstract
Abstract In an acoustic logging system for providing information regarding selected parameters of the wall of a borehole in the earth, and of the rock formation which is adjacent the borehole, in which a single transmit/receive transducer system (T/RTS) mounted on a rotating assembly probes the wall of the borehole in a circular scanning pattern as a function of depth, the improvement which includes at least a second T/RTS mounted on the rotating assembly in known geometrical relation to the first T/RTS, and means to process two or more analog electrical scan signals for transmission over one or more electrical transmission channels in a logging cable. In particular, methods and means are described for transmitting multiple scan signals whereby a higher speed of logging is possible without loss of detail of the logs and without modification of the mechanical system of the logging sonde.
Inventors
- 👤 Robert A. Broding
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:06
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/40; G01V1/44; G01V1/46; E; E21; E21B; E21B47/00; E21B47/002; E21B47/0025; E21B47/08; E21B47/085
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
143 words
A method of logging a borehole which comprises: (a) carrying out scanning operations around the wall of said borehole by directing sonic energy from at least a first and a second nonphysically coincident transmit/receive transducer system in a radial plane around the wall of said borehole and receiving returned reflected sonic energy from reflecting surfaces and producing at least a first and a second electrical scan signal representative of amplitude and transit time of reflected signals from reflecting surfaces at each of a plurality of downhole locations spaced around the wall of said borehole; (b) delaying one of said scan signals until the two scan signals obtained at a respective location representative of amplitude and transit time of reflected signals are coincident in time; and (c) transmitting said time coincident signals representative of amplitude and transit time of reflected signals to the surface.
Claim 2
Independent Claim
143 words
A method of logging a borehole which comprises: (a) carrying out scanning operations around the wall of said borehole by directing sonic energy from at least a first and a second nonphysically coincident transmit/receive transducer system in a radial plane around the wall of said borehole and receiving returned reflected sonic energy from reflecting surfaces and producing at least a first and a second electrical scan signal representative of amplitude and transit time of reflected signals from reflecting surfaces at each of a plurality of downhole locations spaced around the wall of said borehole; (b) delaying one of said scan signals until the two scan signals obtained at a respective location representative of amplitude and transit time of reflected signals are coincident in time; and (c) transmitting said time coincident signals representative of amplitude and transit time of reflected signals to the surface.
Claim 3
Dependent Claim
25 words
The method as in claim 1 in which said first and second scan signals are obtained by operating two transmit/receive transducers of the same frequency.
Claim 4
Dependent Claim
24 words
The method as in claim 1 in which said at least two scan signals are obtained by operating two transit/receive transducers of different frequencies.
Claim 5
Dependent Claim
42 words
The method as in claim 1 in which said transmitting comprises the steps of: (a) converting said at least two scan signals at each location to a higher frequency electrical analog signals; and (b) transmitting said higher frequency signals to the surface.
Claim 6
Dependent Claim
60 words
The method as in claim 4 in which said step of converting comprises the steps of: (a) digitizing said at least two scan signals at a first bit rate and storing said two digitized scan signals in memory; and (b) reading out of said memory said two digitized scan signals at a second bit rate higher than said first rate.
Claim 7
Dependent Claim
20 words
The method as in claim 5 in which said second bit rate is at least twice said first bit rate.
Claim 8
Dependent Claim
83 words
The method as in claim 5 including separate first and second memories, and including the steps of: (a) loading said at least two digitized scan signals into said first memory, then on the next repetition into the second memory, then into the first, and so on at a first bit rate; while (b) reading out said at least two digitized scan signals at a higher bit rate sequentially from said second memory, then said first memory, in opposite phase to said loading step.
Claim 9
Independent Claim
199 words
A method of logging a borehole in a system having a separate cable normally run at a first rate having at least a first signal channel which comprises: (a) carrying out scanning operations around the wall of said borehole by operating at least a first and a second nonphysically coincident transmit/receiver transducer subsystem means: (T/RTS) removed from each other and carried by a sonde and directing sonic energy in a radial plane around the wall of said borehole and receiving return reflected sonic energy from reflecting surfaces and producing at least a first and a second electrical scan signal representative of amplitude and transit time of reflected signals at each of a plurality of downhole locations, spaced around the wall of said borehole; (b) delaying one of said scan signals until two scan signals obtained at a respective location and representative of amplitude and transit time of reflected signals are coincident in time; (c) transmitting said time coincident signals representative of amplitude and transit time of reflected signals to the surface; and (d) recording said at least two time coinicident signals while traversing the borehole with said sonde at a second rate which is higher than said first rate.
Claim 10
Independent Claim
199 words
A method of logging a borehole in a system having a separate cable normally run at a first rate having at least a first signal channel which comprises: (a) carrying out scanning operations around the wall of said borehole by operating at least a first and a second nonphysically coincident transmit/receiver transducer subsystem means: (T/RTS) removed from each other and carried by a sonde and directing sonic energy in a radial plane around the wall of said borehole and receiving return reflected sonic energy from reflecting surfaces and producing at least a first and a second electrical scan signal representative of amplitude and transit time of reflected signals at each of a plurality of downhole locations, spaced around the wall of said borehole; (b) delaying one of said scan signals until two scan signals obtained at a respective location and representative of amplitude and transit time of reflected signals are coincident in time; (c) transmitting said time coincident signals representative of amplitude and transit time of reflected signals to the surface; and (d) recording said at least two time coinicident signals while traversing the borehole with said sonde at a second rate which is higher than said first rate.
Claim 11
Dependent Claim
16 words
The method as in claim 8 in which said two T/RTS are of the same frequency.
Claim 12
Dependent Claim
65 words
The method as in claim 8 in which said two T/RTS are of different frequency, and including the added steps of: (a) separating successive scans of scan signals from said two T/RTS; (b) recording said successive scans of scan signals from a first T/RTS as a first log; and (c) recording said successive scans of scan signals from a second T/RTS as a second log.
Claim 13
Dependent Claim
16 words
The method as in claim 8 in which said second rate is twice said first rate.
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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) | 1988-06-17 | 1988-12-17 | 1989-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-17 | 1992-12-17 | 1993-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-17 | 1996-12-17 | 1997-06-18 | $7700.00 | Window Closed / Lapsed |