CN2858950Y - Drill-following dual-induction resistivity measuring instrument - Google Patents
Drill-following dual-induction resistivity measuring instrument Download PDFInfo
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- CN2858950Y CN2858950Y CN 200520083517 CN200520083517U CN2858950Y CN 2858950 Y CN2858950 Y CN 2858950Y CN 200520083517 CN200520083517 CN 200520083517 CN 200520083517 U CN200520083517 U CN 200520083517U CN 2858950 Y CN2858950 Y CN 2858950Y
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Abstract
A drill-following dual-induction resistivity measuring instrument comprising a collar, a V-shaped groove, a transmit unit, a coupling unit, a receiving unit, a transmitting circuit module, a receiving control circuit module, a pressurized cover plate, an upper slip ring connector, a lower slip ring connector and a wire guide. The instrument adopts double coil system which can detect the resistance of two formations with different radial depths simultaneously. The transmitting coil and receiving coil are independent to each other and each can be adjusted without interferences. They can also be extended and combined to measure drill-following array induction resistivity or multi-coil high resolution drill-following induction resistivity. The measuring result of this instrument can be used to measure real-time true formation resistivity during well drilling, explain formation intrusion condition, calculate formation water saturation, and analyze the variation characteristics of lithology and fluid in the layer where the instrument is in. This is beneficial for adjusting hole trajectory in time according to formation intrusion conditions and controlling the drilling tool to moving along the best location of oil reservoir, thereby is suitable for geologic steering in petroleum drilling engineering.
Description
Technical field:
The utility model relates to a kind of wireless drilling measurer that is used for geosteering in petroleum drilling engineering.
Background technology:
At present, in the measurement while drilling field of drilling well industry, formation resistivity is used for dividing the oil saturation of stratigraphic section and definite reservoir, is the main foundation of well logging evaluation hydrocarbon storage.Knownly comprise with boring side direction resistivity, electromagnetic wave propagation resistivity and with boring induction motor with boring the resistivity measurement technology.
Be provided with electric current with boring shallow side direction resistivity logging by current electrode, in the wellbore stratum, form electric field, measure the distribution of electric field in the stratum, draw formation resistivity.With bore shallow side direction resistivity logging tool with drill bit itself as electrode, 3 button electrodes also can using ring electrode and close drill bit carry out resistivity measurement., invade or before well may damage, just can measure the resistivity of 5～10 centimetres of thin layers as electrode with drill bit at mud; Can carry out high-resolution side direction resistivity measurement with ring electrode, can reduce the influence of country rock, even the true formation resistivity response also can be provided in salt-water mud or high resistivity stratum, and use 3 groups of electrod-arrays, can obtain the resistivity information of 360 ° of scopes of wellbore.
There is following shortcoming in this instrument: the side direction resistivity logging belongs to the DC electrical method well logging, all there is a current electrode that DC current is imported the stratum, measure the current potential of certain point in the well then with a measurement electrode, have only when having conductive drilling mud that current channel is provided in the well just can make in this way.And, need to use the oil-base mud drilling well sometimes in order to obtain stratum initial oil saturation information, even adopt air drilling, under this condition, can not use the DC electrical method well logging.
Adopt many coil array designs with boring the electromagnetic resistivity logger, frequencies of propagation is 1～8MHz, in coil array based on the drill collar structure, coil array is wrapped on the drill collar, by measuring amplitude ratio or phase difference between different spacing receiving coils, and then be scaled formation apparent resistivity, record phase shift shallow resistivity and the dark resistivity of decay.In the ideal case, the longitudinal frame of electromagnetic wave propagation resistivity tool is by the spacing decision of two receiving coils, the survey data of many investigation depths can be used for explaining the intrusion situation, it has been generally acknowledged that the investigation depth of phase resistance rate is more shallow, and the damping resistance rate has bigger investigation depth.
Although can record the resistivity of different investigation depths, there is following shortcoming in this instrument:
At first, the signal frequency that electromagnetic wave resistivity instrument adopts is too high, because electromagnetic wave propagation effect, investigation depth is limited, measurement result can be subjected to influence of geological factors, especially the influence of country rock, the measurement result of instrument not only responds the subterranean formation zone between the receiving coil, and it is relevant to the layer parameter entirely between the receiving coil with transmitting coil, even around the transmitting coil one also can exert an influence than the stratum in the zonule to measurement result, so the longitudinal frame of instrument depends on the resistivity on whole instrument stratum of living in to a great extent.Secondly, the coil of instrument is to be wrapped in the drill collar surface, and its manufacture craft is very complicated, and in use as easy as rolling off a log being worn of coil array and damaging perhaps when borehole size changes, needs coiling again, and the maintenance detection is complexity comparatively, the maintenance cost height.In addition, the same with side direction resistivity, electromagnetic wave resistivity instrument can not be operated in the oil-base mud.
Utilize electromagnetic induction principle with boring induction motor, when passing to the constant alternating current of amplitude and frequency in the transmitting coil, inducing eddy current in the stratum around this coil, eddy current itself can form the secondary alternating electromagnetic field again, do to descend at the secondary alternating electromagnetic field, produce induced electromotive force in the receiving coil, this electromotive force size is relevant with formation conductivity, can obtain formation resistivity by measuring induced electromotive force.
Present adopts a transmitting coil and two receiving coils with the coil array of boring induction logging instrument, one of them is main receiving coil, another is a bucking coil, coil array places the drill collar side to have in the V-shaped groove in reflecting layer, therefore log response has the characteristics of orientation survey to the change in resistance sensitivity of V-shaped groove front regional stratum.Instrument is battery-powered, and a pin thread connector is housed at the battery top, can join with the box connector of instrument bottom, is used for transmitting real time data to measurement while-drilling instrument, and same sensor pipe nipple is applicable to the requirement of different size well.This is 20kHz with the signal frequency of boring induction logging instrument, be significantly less than the frequency of high frequency instrument, therefore be difficult for by formation absorption, investigation depth is dark, and measurement category is bigger, can reach the 0.1-1000 ohm meter, structure design is simple, sensor pipe nipple is applicable to the needs of different size well, and maintenance detects simple, and is applicable to dissimilar drilling fluids.
But there is following shortcoming in this instrument:
This instrument adopts by a transmitting coil and two receiving coil coil arrays that form, that have single fixedly investigation depth, and the formation resistivity of a radial depth of investigetion can only be provided, and can not be used to explain complicated invasion profile and divide permeable formation.For permeable formation, mud is invaded its resistivity is changed diametrically, owing to can only obtain the resistivity value of a radial depth of investigetion in same depth point, therefore can not be used for explaining stratum intrusion situation, can't determine situation and reservoir permeability that the stratum is invaded by mud, be unfavorable for hydrocarbon zone interpretation, thereby can't be used for accurately measuring true formation resistivity.In addition, the dissimilar mud intrusions and the resistivity of different radials depth of investigetion, its oil-gas-water layer feature is different, be subjected to the difference of mud intrusion effect degree according to many different investigation depth resistivity curves, and the difference characteristic that is showed in oil-gas-water layer can be discerned oil gas, so the resistivity measurement of many degree of depth is very important for the well logging during instrument time, but this instrument can't reach this requirement, because its coil array project organization is fixed, each coil array can only provide a kind of resistivity of the degree of depth, obtain the resistivity of different investigation depths, take multiple measurements with regard to handy different coil array, this mode is to be difficult to realize in the engineering practical application.
The utility model content:
The purpose of this utility model is for a kind of double-induction resistivity measuring instrument during drilling is provided, compared with prior art, it is the unit that this instrument adopts two array coils, can measure the formation resistivity of two radial depths simultaneously, the survey data of different investigation depths can be used for explaining stratum intrusion situation, determine situation and reservoir permeability that the stratum is invaded by mud, accurately measure true formation resistivity and calculate the stratum water saturation, reservoir integrated interpretation and oil gas and water analysis technology are improved and perfect.
Instrument described in the utility model comprises drill collar, V-shaped groove, transmitter unit, coupling unit, receiving element, radiating circuit module, reception control circuit module, high pressure sealing cover plate, goes up sliding ring connector, following sliding ring connector, wire guide.
Feature of the present utility model is: coupling unit links together transmitter unit and receiving element to be installed in and forms electrode system in the V-shaped groove, the high pressure sealing cover plate is pressed in the outward flange of V-shaped groove, transmitter unit inside is equipped with transmitting coil and transmitter unit hydro-cushion piston, and receiving element inside is equipped with the deep investigation receiving coil, the deep investigation balance is adjusted swivel nut, deep investigation balance adjustment screw rod, shallow penetration receiving coil, shallow penetration balance adjustment swivel nut, shallow penetration balance adjustment screw rod, receiving element hydro-cushion piston.In the axial both sides of V-shaped groove radiating circuit module and reception control circuit module are installed respectively, the radiating circuit module is made up of exiting signal generating circuit, power amplifier, scale signal generating circuit, the reception control circuit module is made up of memory, microprocessor, clock generator, phase-control circuit, analog-digital converter, wave filter, phase-sensitive detector, amplifier and variable connector, and the radiating circuit module links to each other with receiving element with transmitter unit respectively by wire guide with the reception control circuit module.Inlay sliding ring connector and following sliding ring connector respectively at the screw thread root of drill collar, link to each other with the reception control circuit module with the radiating circuit module respectively by wire guide.
The beneficial effect that double-induction resistivity measuring instrument during drilling described in the utility model has is, this instrument adopts twin coil system, can survey the formation resistivity of two radial depths simultaneously, and transmitting coil and receiving coil are separate, each coil array can independently be adjusted, do not produce and influence each other, can also extend and be combined into boring array induction resistivity or many coil arrays high-resolution with boring induction motor.The measurement result of this instrument not only can be used for measuring in real time true formation resistivity in drilling process, also can be used to explain stratum intrusion situation and calculate the stratum water saturation, differentiate the lithology and the fluid changing characteristic of layer position, instrument place, help in time adjusting well track according to geological information, the control drilling tool runs in the guide the oil reservoir optimum position, is suitable for carrying out in petroleum works geosteering.
Below in conjunction with drawings and Examples the utility model is further specified.
Description of drawings:
Fig. 1 represents the axial section of " double-induction resistivity measuring instrument during drilling ";
Fig. 2 represents the radial section figure of " double-induction resistivity measuring instrument during drilling ";
Fig. 3 represents the circuit block diagram of " double-induction resistivity measuring instrument during drilling ".
1, drill collar 2, last sliding ring connector 3, wire guide
4, radiating circuit module 5, V-shaped groove 6, transmitter unit hydro-cushion piston
7, transmitting coil 8, coupling unit 9, deep investigation balance are adjusted screw rod
10, the deep investigation balance is adjusted swivel nut 11, deep investigation receiving coil 12, transmitter unit
13, shallow penetration receiving coil 14, receiving element 15, high pressure sealing cover plate
16, shallow penetration balance is adjusted swivel nut 17, receiving element hydro-cushion piston
18, shallow penetration balance is adjusted screw rod 19, reception control circuit module 20, following sliding ring connector
21, memory 22, microprocessor 23, clock generator
24, phase-control circuit 25, exiting signal generating circuit 26, power amplifier
27, scale signal generating circuit 28, analog-digital converter 29, wave filter
30, phase-sensitive detector 31, amplifier 32, variable connector
The specific embodiment:
Now, the utility model is further described in conjunction with Figure of description 1,2 and 3.
Fig. 1 and Fig. 2 represent the axial and radial section figure of instrument.Drill collar 1 is positioned at after drill bit or the deflecting tool as the installation skeleton of instrument and the part of down-hole equipment.Have a V-shaped groove 5 in any one side of drill collar, coupling unit 8 links together transmitter unit 12 and receiving element 14 to be installed in and forms electrode systems in the V-shaped groove 5, high pressure sealing cover plate 15 is pressed in the outward flange of V-shaped groove 5, transmitter unit 12 inside are equipped with transmitting coil 7 and transmitter unit hydro-cushion piston 6, and receiving element 14 inside are equipped with deep investigation receiving coil 11, the deep investigation balance is adjusted swivel nut 10, the deep investigation balance is adjusted screw rod 9, shallow penetration receiving coil 13, the shallow penetration balance is adjusted swivel nut 16, the shallow penetration balance is adjusted screw rod 18, receiving element hydro-cushion piston 17.
The array subelement that each receiving coil is made up of main coil and bucking coil, form array coil system with transmitting coil 7, the resistivity of two different radials depth of investigetion can be provided, coupling unit 8 is installed between transmitter unit 12 and the receiving element 14, be used to prevent produce between transmitter unit 12 and the receiving element 14 and slide, and guarantee that these two unit are on the same axial location.The deep investigation balance adjusts screw rod 9 and shallow penetration balance adjustment screw rod 18 is installed in deep investigation balance adjustment swivel nut 10 respectively and the shallow penetration balance is adjusted in the swivel nut 16, and extend to deep investigation receiving coil 11 and shallow penetration receiving coil 13 inside, be used for adjusting the magnetic balance of each receiving coil, the balance adjustment of two coils can independently be carried out, mutually not influence.It is inside and outside pressure that transmitter unit hydro-cushion piston 6 and receiving element hydro-cushion piston 17 are used for counter electrode, damages to prevent electrode system to be subjected to outside mud pressure, and high pressure sealing cover plate 15 guard electrodes system avoids mud pressure and destroys and erosion.
In the axial both sides of V-shaped groove 5 radiating circuit module 4 and reception control circuit module 19 are installed respectively, radiating circuit module 4 is used to produce the pumping signal of transmitting coil 7, microprocessor 22 in exiting signal generating circuit 25 and the reception control circuit module 19 links to each other,, whether work according to measuring the duty that sequential requires control exiting signal generating circuit 25 by microprocessor 22 thereby control whole instrument.Reception control circuit module 19 is used to produce the needed clock signal of instrument work, processing received signal, data acquisition control, survey data storage and Communication Control.These two circuit modules link to each other with transmitter unit 12, last sliding ring connector 2 and receiving element 14, following sliding ring connector 20 respectively by wire guide 3, thereby can make external connection battery provide work used power supply to instrument, and can make measuring-signal be transferred to other measurement while-drilling instrument, transmitter unit 12 and receiving element 14 and circuit thereof separately are convenient to debugging, and make their signal interference reductions each other.
Fig. 3 represents the circuit block diagram of instrument.This equipment circuit with microprocessor 22 as control centre, finish electronic circuit SECO, data acquisition, processing, calculating, storage and with the exchanges data of other measurement while-drilling instrument.
Clock generator 23 adopts same clock source to produce multipath clock, and the internal work sequential and the tranmitting frequency that are used to control all circuit all come from same clock source, thus guarantee between these functional modules accurately synchronously, the reliability of system works is provided.The clock signal that clock generator 23 produces is delivered to microprocessor 22, phase-control circuit 24 respectively.Phase-control circuit 24 is according to the sequential requirement, clock signal is further handled, the multipath clock control signal is provided, its output signal is given exiting signal generating circuit 25, make its triggering work, produce the sine wave exciting signal of a 20KHz, in order in transmitting coil 7, to produce bigger emission current, this pumping signal is supplied with transmitting coil 7 after amplifying through power amplifier 26.Can also produce the scale signal of representing the emission current size by scale signal generating circuit 27 in addition in transmitting coil 7 loops, this signal is used to provide the accurate calibration of instrument.
When passing to the constant AC signal of amplitude and frequency in the transmitting coil 7, in the surrounding space of this coil, induce eddy current, eddy current itself can form the secondary alternating electromagnetic field again, do to descend at the secondary alternating electromagnetic field, deeply, can produce induced electromotive force in the shallow penetration receiving coil 11,13, this electromotive force signal amplitude is very little, is therefore needing it is amplified before further handling, in order to carry out scale accurately, also need the scale signal is done same processing in addition to instrument.Like this, the signal that is input to amplifier has three the tunnel: the scale signal of two-way induced signal that deep investigation receiving coil 11 and shallow penetration receiving coil 13 produce and expression transmitting coil size of current.Microprocessor 22 is according to measuring the sequential requirement, different conditions by control variable connector 32, being respectively these signals provides passage to send into amplifier 31, because amplifier 31 has enough gains, and when frequency is 20KHz, phase shift is very little, so these signals can not produce distortion after being exaggerated.Enter phase-sensitive detector 30 respectively through the signal after amplifying, for each road input signal, under the phase clock control of phase-control circuit 24 outputs, accurately isolate two phase signal components by phase sensitive detection, through entering analog-digital converter 28 respectively after wave filter 29 filtering, and provide data acquisition control and communication signal for analog-digital converter 28 by microprocessor 22, obtain in-phase digital component of signal and quadrature digital signal component, send into microprocessor 22 again and carry out computing, survey data and circuit working state information after handling are kept at memory 21 by the data record format that designs, also can be directly by lead and last sliding ring connector 2 in the wire guide 3, give the pulse telemetry system of measurement while drilling, be sent to ground in real time by it.
Claims (3)
1, a kind of double-induction resistivity measuring instrument during drilling, this instrument comprises: drill collar (1), V-shaped groove (5), transmitter unit (12), coupling unit (8), receiving element (14), radiating circuit module (4), reception control circuit module (19), high pressure sealing cover plate (15), last sliding ring connector (2), following sliding ring connector (20), wire guide (3), it is characterized in that coupling unit (8) links together transmitter unit (12) and receiving element (14) to be installed in forms electrode system in the V-shaped groove (5), high pressure sealing cover plate (15) is pressed in the outward flange of V-shaped groove (5), transmitter unit (12) inside is equipped with transmitting coil (7) and transmitter unit hydro-cushion piston (6), and receiving element (14) inside is equipped with deep investigation receiving coil (11), the deep investigation balance is adjusted swivel nut (10), the deep investigation balance is adjusted screw rod (9), shallow penetration receiving coil (13), the shallow penetration balance is adjusted swivel nut (16), the shallow penetration balance is adjusted screw rod (18), receiving element hydro-cushion piston (17).
2, double-induction resistivity measuring instrument during drilling according to claim 1, it is characterized in that installing respectively radiating circuit module (4) and reception control circuit module (19) in the axial both sides of V-shaped groove (5), radiating circuit module (4) is by exiting signal generating circuit (25), power amplifier (26), scale signal generating circuit (27) is formed, reception control circuit module (19) is by memory (21), microprocessor (22), clock generator (23), phase-control circuit (24), analog-digital converter (28), wave filter (29), phase-sensitive detector (30), amplifier (31) and variable connector (32) are formed, and radiating circuit module (4) links to each other with receiving element (14) with transmitter unit (12) respectively by wire guide (3) with reception control circuit module (19).
3, double-induction resistivity measuring instrument during drilling according to claim 1, the screw thread root that it is characterized in that drill collar (1) is inlayed sliding ring connector (2) and following sliding ring connector (20) respectively, is linked to each other with reception control circuit module (19) with radiating circuit module (4) respectively by wire guide (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520083517 CN2858950Y (en) | 2005-05-27 | 2005-05-27 | Drill-following dual-induction resistivity measuring instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520083517 CN2858950Y (en) | 2005-05-27 | 2005-05-27 | Drill-following dual-induction resistivity measuring instrument |
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| Publication Number | Publication Date |
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| CN2858950Y true CN2858950Y (en) | 2007-01-17 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200520083517 Expired - Fee Related CN2858950Y (en) | 2005-05-27 | 2005-05-27 | Drill-following dual-induction resistivity measuring instrument |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1869400B (en) * | 2005-05-27 | 2010-12-08 | 中国石化集团胜利石油管理局钻井工艺研究院 | Double-induction resistivity measuring instrument during drilling |
| CN102337886A (en) * | 2010-07-22 | 2012-02-01 | 中国石油天然气集团公司 | System of performing down-hole measurement on oil gas in slurry while drilling |
| CN108071385A (en) * | 2016-11-17 | 2018-05-25 | 中国石油化工股份有限公司 | A kind of measuring method and circuit with brill electromagnetic resistivity Amplitude Ration and phase difference |
| CN109138995A (en) * | 2018-08-13 | 2019-01-04 | 中国石油集团工程技术研究院有限公司 | When a kind of drilling tool rotates with boring apparent resistivity measuring system and method |
| CN110792422A (en) * | 2018-07-16 | 2020-02-14 | 中国石油化工股份有限公司 | Device and method for measuring lateral resistivity while drilling |
-
2005
- 2005-05-27 CN CN 200520083517 patent/CN2858950Y/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1869400B (en) * | 2005-05-27 | 2010-12-08 | 中国石化集团胜利石油管理局钻井工艺研究院 | Double-induction resistivity measuring instrument during drilling |
| CN102337886A (en) * | 2010-07-22 | 2012-02-01 | 中国石油天然气集团公司 | System of performing down-hole measurement on oil gas in slurry while drilling |
| CN102337886B (en) * | 2010-07-22 | 2014-11-26 | 中国石油天然气集团公司 | System of performing down-hole measurement on oil gas in slurry while drilling |
| CN108071385A (en) * | 2016-11-17 | 2018-05-25 | 中国石油化工股份有限公司 | A kind of measuring method and circuit with brill electromagnetic resistivity Amplitude Ration and phase difference |
| CN108071385B (en) * | 2016-11-17 | 2021-03-16 | 中国石油化工股份有限公司 | Method and circuit for measuring electromagnetic wave resistivity amplitude ratio and phase difference while drilling |
| CN110792422A (en) * | 2018-07-16 | 2020-02-14 | 中国石油化工股份有限公司 | Device and method for measuring lateral resistivity while drilling |
| CN110792422B (en) * | 2018-07-16 | 2023-02-03 | 中国石油化工股份有限公司 | Device and method for measuring lateral resistivity while drilling |
| CN109138995A (en) * | 2018-08-13 | 2019-01-04 | 中国石油集团工程技术研究院有限公司 | When a kind of drilling tool rotates with boring apparent resistivity measuring system and method |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070117 |