SU652517A1 - Apparatus for acoustic logging of oil and gas wells - Google Patents

Description

 -, The invention relates to the field geophysical surveys, wells, intended for geophysical studies by acoustic methods of the absorbing properties of rocks in natural conditions and can be used in field geophysics. The known devices 1, 2, 3 к | 4 used for this purpose allow to determine the geological parameters of rocks by measuring the velocity of propagation of elastic oscillations in the studied medium and the logarithmic decrement of attenuation of the longitudinal or transverse pulsed acoustic signal. The closest technical solution to the proposed invention is A 5j device containing a three-element acoustic probe, a number of amplitude parameters of an acoustic signal, a discriminator in the selection device. sinhroimpulsozz switching tryg Gaia source follower, regystragor disadvantage of known devices studies borehole environment by acoustic methods is unreliability of isolating the first entry posdolnoy pulsed wave acoustic signals coming from the emitter to the receiver of the acoustic probe. This unreliability is due to acoustic noise and the imposition of various types of waves, the excitation of dixes in the near wellbore. The accuracy and efficiency of determining the geological parameters of the environment by acoustic logging methods are reduced in the reulugage. long-range receivers acoustic probe. The goal is achieved by the fact that the proposed equipment for acoustic logging of oil and gas wells contains a camshaft ratio of the energies of acoustic shunt signals, the input of which is connected to the output of the acoustic probe, and the output through the source follower is connected to registrators. The energy ratio indicator of pulsed acoustic signals contains a charging circuit, a discharge circuit and a storage capacitor, other inputs of the charging circuits are connected to the output of the acoustic probe, and the outputs are connected to a storage capacitor and a source follower. The charge circuit contains a differentiating capacitor, a current repeat gel that forms a capacitor, a normally open electr. (On-key, a voltage-to-current converter, an inductance coil and a diode, the input of the charging circuit through a differentiating capacitor connected to the output of the acoustic probe, the output of the differential the capacitor is connected to the input of the current repeater, the output of which is connected to the non-grounded circuit of the forming capacitor, the input of the electronic switch and the input of the voltage-current converter, There is no other ground coil output and the anode of the diode, the cathode of which is connected to an ungrounded memory cell. The discharge circuit contains a differentiating capacitor, a current repeater, a forming capacitor, a normal electronic key, a converter, and a voltage supply. the transistor and the bias voltage source, with the output of the discharge circuit: through the differentiating capacitor connected to the output of the acoustic probe, the output of the differentiating capacitor with The one with the input current of the current repeater, the output of which is connected to the ungrounded input of the forming capacitor, the input of the electronic key and the input of the voltage converter GOK, the output of the converter is connected to the non-grounded input coil of the inductance and the emitter of the transistor, to the base, the source of the bias voltage is switched on, and the collector is connected to the ungrounded pole of the inhibiting capacitor, the electronic switches of the charging and discharging circuit have two controllable inputs and There is no connection to the output of the discriminator, the input of which is connected to the output of the acoustic probe, and the second control inputs are connected to the output of the three-switching commutator. FIG. 1 shows a block diagram of the proposed acoustic logging equipment; Fig. 2 shows diagrams of signals in the corresponding points of the block diagram. The equipment consists of a three-element acoustic probe 1 with acoustic transducers 1-1, 1-2, 1-3, lowered into well 2, and a calculator 3 of temporal and amplitude parameters of impulse acoustic signals. signals, discriminator 4, device: 5 extraction of sync pulses, trigger 6, meter 7 energy ratio of pulsed acoustic signals; containing two differentiating capacitors 7-1, 7-2, two current repeaters 7-3, 7-4, two forming capacitor 7-5, 7-6, two n Normally open electronic switches 7-7, 7-8, two voltage-current converters 7-9, 7-10, two inductors 7-11, 7-12, diode 7-13, transistor 7-14, memory capacitor 7 -15, source repeater 8, discriminator 9, registrator 10, source of mixing voltage, i When exposed to supply voltage pulses on the radiator 1-1 of the acoustic probe 1. elastic oscillations are excited, which spread in the environment of well 3 attenuate in it and after some time interval reach receivers 1-: 2, 1-3. In the receivers, the uptrend oscillations are converted into electrical signals and, in turn, enter the amplification and transmission path on the day surface. At the moment the radiator triggers, a sync pulse arrives in the transmission path. The full signal at the output of the acoustic probe is shown in FIG. 2a The probe signal arrives and the transmitter 3 temporal and amplitude parameters of the acoustic signal, where the time is measured, during which the elastic oscillations of the radio are lost in the medium in the path equal to the distance between the receivers 1-2, 1-3, and the logarithmic decrement of the elastic decay fluctuations. At the same time, the probe signal is fed to the input of the discriminator 4I through differentiating capacitors 7-1, 7-2, to the inputs of current repeaters 7-3, 7-4, meter 7, the ratio of the energies of the acoustic signals. At the output of the discriminator 4, voltage pulses are formed (FIG. 26), the front and rear fronts of which co-ordinate the transition moments by acoustic signals.

zero line oscillations. From the output of the discriminator 4, the voltage generated voltage pulses are fed to the input of the trigger pulse 5, the release of sync pulses, which are fed to the counting switch of trigger 6 to form switching pulses (Fig. 2c). The voltage pulses from the trigger output go to the control inputs of the keys 7-7 and 7-8. Under the action of the after-switch, the switch 7-7 closes and thereby short-circuits the capacitor 7-5 for the transit time of the signal of the far receiver 1-3, and the switch 7-8 closes for the transit time of the near reception signal Ka 1-2

 When the impulse voltage of the near-receiver signal arrives at the input of Iporig 7, a differential capacitor 7-1; through the differentiator 7-3 and the forming capacitor 7-5 will flow current of negative polarity. Each current pulse charges the capacitor 7-5 from some voltage proportional to the amplitude value of the input signal. Upon termination of each current pulse, charge is reset from Capacitor 7-5 using key 7-7. Key 7-7 is controlled by the falling edges of the pulses (FIG. 26) arriving at the first control input. On the capacitor 7-3, voltage pulses are formed with steep trailing edges (fkg 2g)

When the meter 7 pulses the voltage of the far receiver signal to the input, through the differentiating capacitor 7-2, the current repeater 7-4 and the forming capacitor 7-6, current pulses of positive polarity flow. Each current pulse charges the capacitor 7-6 to a voltage proportional to the amplitude value of the signal from the far receiver. The charge accumulation from the capacitor 7-6 is made with the help of КЛ15ча 7-8. Key 7-8 is controlled by the leading fronts of the Pulses (FIG. 26), also arriving at its first control input.

A voltage waveform on capacitor 7-6 is shown in FIG. 2d,

Pnee voltage pulses from a capacitor 7-5 are converted by a converter 7-9 to current pulses, which are fed to the charge of an inductance 7-11. Under the action of each current pulse, the coil receives energy equal to L where 1 is the amplitude value of the current pulse, B - coil inductance 7–11. At the moment of the end of a gok pulse, a voltage jump of self-induction is formed on the coils, & OTO ry opens a diode 7–13, and coil 7–11 gives the memory to the capacitor 7–15 previously accumulated energy, total charge reported to the memorizing capacitor acoustic pulse receiver low siGnayom

. - the ratio is proportional to: where;

 - the amplitude of the value of the 1st

input signal fluctuation:

C is the average value of the voltage on the capacitor 7-15.

Similarly, the voltage pulses from the capacitor 7-6 are converted into this transducer 7-10 into current pulses, which are fed to the coil 7-12 together with each time the energy

L 2 - the value of inductance of the coil 7-12.

The back front of the gok pulse generates a voltage jump on the coil 7-12. At the moment when the voltage of the cat 7-12 is equal in magnitude 1 to the source of the mixing source, the transistor 7-4 opens and the memory is removed from the memory.

... 2 2 Up

where A is the amplitude value of the i-th oscillation of the signal from the far receiver.

The total charge removed by the pulsed acoustic signal (dyeas) of the receiver is 9. ..

and 2Uo

To determine the voltage across the storage capacitor, we write the current balance equation

ii

du

- m

JT1 O dt

20 2U "

where C is the capacitance of the capacitor 7-15; rtinastota launch emitter.

The solution to this equation is under initial conditions, O EO

After termination of the transition process on the capacitor 7-15 is established, the voltage

SA

IR,

Claims (4)

where c is the mass coefficient of the ratio of the energies of 1 and E to them of the acoustic signals. The output voltage O of the meter 7 arrives at the input of the recorder 10 through the source driver 8 and simultaneously with the output signals of the calculator 3 is continuously recorded on the diagram band. Since the measurement of the ratio of the energies of the acoustic signals and other interfering factors influence slightly, since their amplitude is much less than the average amplitude of the information signal, then the introduction of the measuring instrument of the energy ratio of the pulsed acoustic signals into the known acoustic logging equipment will allow to improve the accuracy and efficiency of determining by physical methods the physical properties of the near-wellbore medium. In order to properly synphate the system to a section of channels, in the proposed equipment, a discriminator 9 is used, the input of which is connected to the output of the energy ratio meter, and the output of the discriminator is connected to the trigger input of the zero setting trigger. The synphase condition is realized by the sign: the energy of the acoustic signal E of the near receiver is always greater than the energy of the Eg.aKystical signal of the long-range receiver. Consequently, with proper synphasing, the voltage across the storage capacitor is always numerically greater. . Kf. If the channel reassignment system fails to phase out, the output voltage of the meter 7 becomes less than KQ. At the moment when the output voltage and se-KQ the discriminator 9 is triggered. As a result, a pulse is generated, which acts on. R - trigger input 6, returns the channel separation system to a normal state. Claims I. Inventory equipment for acoustic logging of oil and gas wells, containing a three-element acoustic probe, calculator. temporal and amplitude parameters of the acoustic signal, the discriminators of the bandwidth, the synchro pulses extraction device, the switching trigger, the source follower and the recorder, from the fact that, in order to improve the accuracy and efficiency of determining the absorbing properties of mining rocks by changing energy ratio of the pulsed acoustic signals of the near and far receivers of the acoustic probe; it contains a measuring instrument for the ratio of the energies of the pulsed acoustic signals, the input of which is connected to the output of an ac an oral probe, and the output through the source follower is connected to the recorder. 2. An apparatus according to claim 1, wherein the energy ratio meter of pulsed acoustic signals contains a charging circuit, a discharge circuit, and a storage capacitor, the inputs of the charging circuits are connected to the output of the acoustic probe, and the outputs are connected to a storage capacitor and a source one. repeater. 3, Apparatus according to paragraphs. 1 and 2, which means that the charging circuit contains a differentiating capacitor, a current repeater forming the capacitor, a normally open electronic key converter Voltage, an inductor and a diode, and the input of a negative circuit through the differentiating capacitor is connected to the output acoustic probe, the output of the differentiating capacitor is connected to the input of a current follower, the output of which is connected to an ungrounded vshsom of a formaid capacitor, an input of an electronic key and an input of voltage-current transducer, voltage-current transducer output is connected to the ungrounded inductance terminal and the diode anode whose cathode is connected to the ungrounded pole of the storage capacitor. 4a Equipment for PP. 1-3, that is, that the discharge circuit will be enclosed by a differentiating capacitor, TX5KOVY, a forming capacitor, a normally open electronic key, a voltage converter, an inductance coil, a transistor, and a STOCHNIK bias voltage, and the course of the discharge circuit through a differentiated capacitor is connected to the output of the hortic probe, the output of the differential capacitor is connected to the input of the current p. Iteptep, the output of which is connected to the ungrounded input of an internal5 capacitor, an elec- tron input a key input transducer April voltage-current converter output oedinen with ungrounded terminal to gugiki indukgivnosgi emiggerom granzysgora and in which there is a source base bias voltage and whose collector is connected to the IM nezazemlenH pole of the storage capacitor. 5. Equipment on PP. 1-4, about t l. In addition, the electronic keys of the charging circuit have control inputs, the first control inputs are connected to the discriminator output, the input of which is connected to the output of the acoustic probe, and the second control inputs are connected to exit switch trigger. Sources of information taken into account in the examination 1. US Patent No. 327О1316, cl. 34O-18, 1966. 2. US patent number 3177467, CL 340-15, 1965. 3. US Patent No ZON51O29, cl. 181-5, 1960. 4. US patent number 3362011, cl. 181-5, 1967. about. Integrated acoustic logging equipment JV A K-2, Sat. Geophidic instrumentation, vol. 48, Nedra 1972, p. 83-88. "Y Y