CN2055181U

CN2055181U - Acoustic amplitude logging instrument

Info

Publication number: CN2055181U
Application number: CN89214438U
Authority: CN
Inventors: 郭清晨
Original assignee: XIAN PETROLEUM PROSPECTING INSTRUMENT GENERAL FACTORY
Current assignee: XIAN PETROLEUM PROSPECTING INSTRUMENT GENERAL FACTORY
Priority date: 1989-07-17
Filing date: 1989-07-17
Publication date: 1990-03-28

Abstract

The utility model relates to an improved acoustic amplitude logging instrument for inspecting cementing quality for petroleum, geology, etc. As a logging down instrument is provided with the power amplification circuit of straight coupling complete complementary output OTL and an emitting balancing resistor R-[p], and a ground instrument is provided with the band pass filter of 20KHz, a positive peak detector, etc., for measuring dynamic ranges, decreasing baseline interference, the sensitivity and the accuracy of the complete machine, and other aspects, the acoustic amplitude logging instrument are totally superior to the existing acoustic amplitude logging instruments. The acoustic amplitude logging instrument is designed for mid-deep well conditions; the temperature resistance of the utility model is 155 DEG C, and the pressurization is 100MPa.

Description

Acoustic amplitude logging instrument

The utility model releases a kind of oil, geology etc. of being applicable to and checks the acoustic amplitude logger device of cementing qualities, and more precisely, it is a kind of acoustic amplitude log tools that improved.

The quality of cementing quality, directly influence formation testing, oil recovery and the water filling work of oil well, in production practices, often run into because acoustic amplitude logging unreliable, cause the false judgment on the cementing quality, its result will cause blindly squeeze method or in the well completion work of scurrying under the groove situation, waste a large amount of manpower and materials, and have endless trouble.Therefore, the reliability of raising acoustic amplitude logging is main to closing.

As everyone knows, the basic principle of acoustic amplitude logging is to measure on cement and the sleeve pipe cement plane, the attenuation change situation of the first peak-to-peak amplitude of acoustic signals, when cementing, the first peak-to-peak amplitude of the acoustic signals that is measured is little, during weak bonding, first peak-to-peak amplitude is big, judges the bonding quality of cement and sleeve pipe with this.But the factor that influences the first peak-to-peak amplitude of acoustic signals is a lot: the existence of microgap will make the first peak-to-peak amplitude that measures increase; Downhole cartridge departs from borehole axis will make the first peak-to-peak amplitude that measures reduce; Normal base line disturbs the first peak-to-peak amplitude that measures will be increased; Negative baseline interference will make the first peak-to-peak amplitude that measures reduce; The power of the measurement dynamic size of instrument itself, the height of measuring sensitivity, inhibition interference performance all can cause the inaccurate of measurement result.

The main reference prior art is as follows:

1. " improve the criterion of cementing quality inspection work ", the BF Mcgee, HL microcaloire, Ou Yangchangsheng are translated " logging technique " 1982,2.

2. " discussion of the test of Acoustic amplitude logging influence factor and acoustic amplitude logging scale ", North China oil well logging company " logging technique " 1981,10.

3. " simulated test of the scales influence factor of sound width of cloth standard of instrumentsization and simulation well ", well logging group of grand celebration probing company " logging technique " 1981.10.

4. the GJ75 type middle-deep well cement bond logging instrument produced of Xi-an Petroleum Prospecting Instrument Gen. Factory.

In order further to satisfy on-the-spot well logging actual needs, improve and use acoustic amplitude logging to solve the problem that cementing quality exists at present, must be improved existing instrument, mainly be measurement dynamic range, reduction baseline interference, raising instrumental sensitivity and the precision that enlarges instrument, these are the purpose of this utility model and task.

Task of the present utility model is finished like this:

One. enlarge measurement dynamic range, the sensitivity of raising apparatus measures of downhole cartridge amplifying circuit: with reference to Fig. 1, in the acoustic amplitude logging, when cement and sleeve pipe cement fully, the amplitude at the first peak of casing wave is approximately about 10mv, when cement and sleeve pipe not glued fully (being so-called empty sleeve pipe), be approximately about 600mv, therefore, this just requires the downhole cartridge amplifying circuit that enough big dynamic range must be arranged, promptly undistorted when peak signal (not intact glued), can discern minimum signal (glued fully) again reliably.For this reason, the downhole cartridge amplifying circuit is selected the full complementary output OTL power amplifier that always is coupled, its power output stage V for use ₄, V ₅Adopt the wide warm area transistor of novel NPN and PNP complementary pairing, symmetry is good, all is better than general circuit, the input stage V of this amplifying circuit at non-linear distortion, instant response and temperature performance etc. ₁, V ₂Also adopt the transistor of different conduction polarity respectively, in order to improve the stability of this amplifying circuit, V ₁Emitter resistance R ₅Receive power output stage V ₄And V ₅Mid point, form strong interpolar negative feedback network, resistance R is set in the circuit ₄And R ₉Be in order to make power output stage V ₄And V ₅Keep mid-point voltage also its static working current to be adjusted, all enough big multiplication factor, resistance R can be arranged when making whole amplifying circuit operate in supply voltage positive direct-current 60V～100V ₃And R ₅Ratio (R ₃/ R ₅) determined the gain of circuit.

Two. reduce baseline interference, improve and believe/make an uproar ratio, increase the small-signal detecting reliability, measure has two:

One is with reference to Fig. 2, for making baseline straightening, in the downhole cartridge radiating circuit, at emission transformer T _FThe secondary in parallel one adjustable balance resistance R that _P, its resistance is generally 〉=470K Ω, and it can be a potentiometer, also can be two series resistances, if the former, the necessary ground connection of center head, if the latter, must ground connection between two resistance.This be because: the factor that produces baseline interference is a lot, but mainly is that the high-voltage pulse that radiating circuit produced causes eddy current and because the interference that the asymmetric grade of lead-in wire is caused at downhole probe center tap place.Fig. 3 has provided verification tube signal, and Fig. 4 is the balancing resistance R _PBefore baseline be 〉=| 150|mv, Fig. 5 are the balancing resistance R _PBack baseline≤| 10|mv.

Its two, with reference to Fig. 6, as mentioned above, baseline interference is mainly come the spontaneous emission synchronous interference, though bigger improvement has been arranged because of having added above-mentioned measure, eliminate synchronously and other noise jamming for basic, be provided with one by operational amplifier N at ground instrument measuring circuit inlet ₁The low reactance-resistance ratio bandpass filter that constitutes, its centre frequency is 20KHZ ± 2KHZ, and useful 20KHZ is passed through, and the clutter of 20HZ synchronous interference and other frequency is filtered, and makes the baseline of ripple survey signal very straight to the greatest extent, has improved the letter/ratio of making an uproar, in order to make this circuit filtering stable performance, R in the circuit ₁₃, R ₁₄, R ₁₅, R ₁₆, R ₁₇All select the RJ-0.5W high temperature resistance for use.Fig. 7 be baseline before the bandpass filtering≤| 10|mv, Fig. 8 are that baseline value is bordering on desirable zero base line behind the bandpass filtering.Above-mentioned wave filter can be calculated as follows:

Centre frequency f ₀=√ 2/RC,

Quality factor q=√ 2/(5-K), K=1+R wherein ₄/ R ₅,

Multiplication factor K ₀=K/(5-K).

Three. improve the range of linearity and the certainty of measurement of ground instrument measuring circuit: with reference to Fig. 9, the range of linearity of measuring circuit and certainty of measurement, final decision the sensitivity and the precision of complete machine, the utility model has been selected the AC-DC translation circuit of a positive peak wave detector as B point signal, N for use ₂Be phase comparator together, N ₃Be a follower, the two passes through resistance R _FHave strong feedback, circuit is stable, and operating principle is as follows:

1. as input signal V ₁Be timing, comparator N ₂Just be output as, and through just meeting diode V ₇Give capacitor C ₁Charging is because of resistance R ₁₈Numerical value is enough big, capacitor C ₁Discharge be very slowly.

2.N ₃Be a follower, capacitor C ₁On voltage by follower N ₃Through resistance R _FFeed back to comparator N ₂End of oppisite phase, as the comparative voltage of in-phase end, when feedback voltage (is C ₁On voltage) during less than the input voltage of in-phase end, input signal will continue to give capacitor C ₁Charging is up to comparator N ₂When the feedback voltage of end of oppisite phase equates in the input voltage of in-phase end, comparator N ₂Be output as zero, detector diode V ₇Biasing, charging stops, at this moment capacitor C ₁On charging voltage reached the peak value of positive input signal.

3. as input signal V ₁During decline, comparator N ₂Output end voltage be lower than capacitor C ₁On voltage, detector diode V ₇Continue biasing, therefore, capacitor C ₁On voltage be not subjected to the influence of input signal, just through resistance R ₁₈Slowly discharge (voltage maintenance).

4. diode V ₆To detector diode V ₇PN junction carried out voltage-drop compensation, to improve the sensitivity of small-signal, detector diode V ₇Guarantee that the positive signal peak value is to capacitor C ₁Charging, negative peak is inoperative, so, when next positive peak signal arrives, will repeat said process, thus the time showed the AC-DC conversion.

5. experiment showed, comparator N ₂With follower N ₃Adopt operational amplifier μ A741, but preferably select the operational amplifier F3140 of high speed high resistant for use.

Technology described in the utility model is used in the GJ85 type middle-deep well acoustic amplitude log tools that Xi-an Petroleum Prospecting Instrument Gen. Factory is about to go into operation.

Figure 13 is the downhole cartridge circuit diagram, wherein launches balance resistance R _PAdopt high temperature resistant potentiometer, its value is 470K Ω, V ₈Select GK5A/185 ℃ of high temperature controllable silicon for use, transmitting probe BCT selects 12 high temperature crystal of niobium lithium for use, the emission resistance R ₀Be reduced to 330 Ω (three RJ-2W-1K parallel connections) by former 1K Ω, improve the temperature performance of radiating circuit.V ₁～V ₅Form acoustic signals and receive amplifying circuit, V ₁, V ₅--3CA1KW, V ₂, V ₃, V ₄--3DA1KW, C ₂, C ₃, C ₆--CA5/S-125V high temperature tantalum electrolytic capacitor, C ₁, C ₄--high temperature is washed the human relations capacitor, and receiving transducer BCR selects 8 high temperature crystal of niobium lithium for use.

Figure 14 is ground instrument measuring circuit figure, wherein by operational amplifier N ₂The bandpass filter of being formed, N ₂--the μ A741 operational amplifier of industrial general, for guaranteeing the stable of centre frequency, R ₁₃～R ₁₇All select RJ for use ₂-0.5W high temperature resistance, R ₁₃-100K Ω, R ₁₄-100K Ω, R ₁₅-100K Ω, R ₁₆-13K Ω, R ₁₇-36K Ω, capacitor C ₇, C ₈Select the CYZ mica condenser for use, C ₇-100P, C ₈-100P.D ₁Be storbing gate, select CD4066 four bidirectional analog switches for use, its input is A point waveform, and is shown in Figure 10, and output is B point waveform, and is shown in Figure 12, and Figure 11 illustrates the gate-control signal of control storbing gate.

Among Figure 14 by operational amplifier N ₂And N ₃The positive peak wave detector of forming of B point signal being done the AC-DC conversion, N ₂, N ₃Select F3140 for use, R ₁₈-15 Ω, V ₆, V ₇Select 1N914 for use, R _F-100K Ω, C ₁-0.1 μ f, R ₁₉-2M.

GJ85 middle-deep well acoustic amplitude log tools described in the utility model compare with domestic like product, have the following advantages:

1. downhole cartridge amplifying circuit dynamic range is big, and is highly sensitive: power supply 60～100V direct current, and 15～30 times of multiplication factors, input signal 5～2000mv all can linearly amplify.

2. the downhole cartridge temperature performance is good, working stability: temperature is elevated to 155 ℃ from room temperature, and constant temperature one hour, output linearity is changed to≤and ± 50 ‰.

3. baseline interference is little, believes/makes an uproar than height: during input 1000mv, baseline is done

Disturb≤± 10mv, direct current is output as zero μ A.

4. ground instrument measuring circuit precision height, it is little to be overlapped the peak operating influence: the range of linearity

100～1000mv, error≤± 20 ‰.

Claims

1, a kind of acoustic amplitude log tools is characterized in that: the downhole cartridge amplifying circuit is by transistor V ₁～V ₅Form the full complementary output OTL power amplifier of straight coupling and constitute, its supply voltage is 60 volts to 100 volts of positive direct-current.

2, according to claim 1 described acoustic amplitude log tools, it is characterized in that: power output stage V ₄, V ₅Adopt NPN and the wide warm area transistor of positive-negative-positive complementary pairing.

3, acoustic amplitude log tools according to claim 1 is characterized in that: the input stage V of power amplifier ₁And V ₂Adopt the transistor of different conduction polarity, i.e. V ₁Be positive-negative-positive, V ₂Be the NPN type.

4, according to claim 2 or 3 described acoustic amplitude log tools, it is characterized in that: V ₁Emitter resistance R ₅Receive power output stage V ₄And V ₅Mid point, form strong interpolar direct current negative feedback network.

5, acoustic amplitude log tools according to claim 1 and 2 is characterized in that: change regulating resistor R ₄Resistance, make power output stage V ₄And V ₅Keep mid-point voltage, resistance R ₉Setting, make the power output stage V when different supply voltages (60V～100V) ₄And V ₅Static working current adjusted.

6, acoustic amplitude log tools described in the utility model, its spy is: in the downhole cartridge radiating circuit, emission transformer T _FA secondary balance resistance R in parallel _P, its resistance is 〉=470K Ω.

7, acoustic amplitude log tools described in the utility model is characterized in that: ground survey instrument circuit inlet adds one by operational amplifier N ₁The low reactance-resistance ratio bandpass filter that constitutes, its centre frequency is 20KHZ ± 2KHZ.

8, acoustic amplitude log tools according to claim 7 is characterized in that: resistance R ₁₉, R ₁₄, R ₁₅, R ₁₆, R ₁₇All adopt the RJ-0.5W high temperature resistance.

9, acoustic amplitude log tools according to claim 7 is characterized in that: operational amplifier N ₁That adopt is μ A741, and that best is F3140.

10, acoustic amplitude log tools described in the utility model is characterized in that: in the instrument measuring circuit of ground, what B point signal was done the AC-DC conversion is by phase comparator N together ₂With a follower N ₃By feedback resistance R ₁The positive peak wave detector of forming with strong feedback.

11, acoustic amplitude log tools according to claim 10 is characterized in that: with phase comparator N ₂Output rectify and to meet a detector diode V ₇Guarantee that positive peak is to C ₁Charging.

12, according to claim 10 or 11 described acoustic amplitude log tools, it is characterized in that: with phase comparator N ₂Output and inverting input between a diode V in parallel ₆, as to detector diode V ₇The PN junction voltage-drop compensation.

13, according to claim 10 or 11 described acoustic amplitude log tools, it is characterized in that: resistance R ₁₈Resistance be 10～20 Ω.