SU1462215A1 - Device for acoustic well logging - Google Patents

Abstract

The invention relates to the field of geophysical exploration wells, namely, the acoustic logging device. The invention is an increase in the accuracy of measurements by registering the kinematic characteristics of various types of waves in each cycle of operation of the radiators. The device records the time of any signal phase specified at the beginning of the measurements that falls within the confidence interval with a width of less than half the signal period. A memory device, a memory address counter, a control device and a switch are additionally introduced into the device. 1 il. F SL

Description

The invention relates to the field of geophysical well research.

The purpose of the invention is to improve the measurement accuracy by registering the climatic characteristics of various types of waves in each cycle of operation of the radiators.

The drawing shows the functional diagram of the device., (

It contains the threshold device 1 at one input which receives a signal from the downhole tool, and at the other the synchronization pulses from the control device 2. The output of the threshold device is connected to the information input (D1) of the storage device 3. The storage device (memory) is one-bit, with a capacity of 1024

bits and sampling time not more than 500 NS. Bxqg write-read control (WE / PE) The memory is connected to the corresponding output of the control unit. Information from the output of the charger sends-, from one of the inputs of the control device, to the other two inputs of which the synchronization pulses C1 and C2 come from the downhole tool. On

address inputs Zu-A (A1, A2

A, TO) receives a 10-bit binary code from the corresponding outputs of the 10-bit binary reversing counter of the address 4 of the charger, the direct (+1) and reverse (-1) counting inputs, setting the counter to zero (RO) and storing the start address is connected to the corresponding outputs of the control unit. Counter outputs

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the memory addresses are also connected by the corresponding outputs D (Df, D2,.,., D10) of registers 5, 6, respectively, of the current values of the measured parameters t, and t;,. The control inputs of the register information are connected to the corresponding outputs of the control-: laziness device. Register outputs are connected

1 MHz, corresponding to the moments of transitions of the incoming signal phases through the threshold level. These times are recorded in the memory in the form of units recorded at addresses whose binary codes correspond to these times. As soon as all are sampled

 with the corresponding inputs 10-bit 1024 cells 3 control unit; whom two :: anal, switch 7, stops issuing pulses to the input

which is switched by signals arriving at its inputs C1 and C2 from the control unit. The switch outputs are connected to the corresponding inputs of the initial setup of the address D (D1, D2v ..., D10) of the 5U address counter. The inverse outputs of register 5 and direct register 6 are connected to the corresponding inputs of a 10-bit binary adder 8, the output of which is the 10-bit binary code of the parameter & t-P. The outputs of registers 5 and 6 and the adder are connected to the inputs of the corresponding digital-analog converters 9, 10 and 11. From the outputs of the registers and the adder and from the outputs of digital-analog converters, digital and analog signals are sent to external devices,

The device works as follows.

Consider the case when the near-emitter of the downhole tool worked. At the same time, the control device receives a signal C1 and it starts immediately inputting a charger to the input of a direct counting +1 of the address of the charger, the frequency of which is stabilized by quartz and is equal to 1 MHz. The memory address counter, which is preset to the zero state, starts counting in the forward direction. The signals from the outputs of the address counter 4 of the charger, arriving at the address inputs of the charger, sequentially select its cells from the first to the last. At ets | m, a signal is received from the control unit to the input of the WE / PE memory device allowing recording of information in the memory. Prior to the arrival of an acoustic signal exceeding the level of the threshold device, the latter outputs a zero signal to the information input of the memory, which is recorded sequentially in each memory cell. But, as soon as an acoustic signal arrives at the input of the threshold device, it will start i to output to the memory input pulses synchronized with a frequency of 1 MHz, corresponding to the moments of transitions of the incoming signal phases through the threshold level. These times are recorded in the memory in the form of units recorded at addresses whose binary codes correspond to these times. As soon as all are sampled

+1 of the address of the memory device and prohibits the recording of information in the memory. Thereby, the trigger points of the threshold device on the phases of the acoustic signal are fixed in the memory. Subsequently, the instant of triggering the threshold device for the desired signal phase is found. Device

the control issues an input from the counter of the address of the memory device to enter information. In this case, the code stored in the register is entered into the memory address counter.

the current value of the parameter t ,, so

five

0

five

0

as a switchboard of signals coming from the control unit to its input C1, it transfers information from the outputs of register 5 to the corresponding inputs of the memory address counter. Thus, the code corresponding to the value of the parameter t in the previous cycle of operation of the radiator of the downhole tool is entered into the memory address counter. Then, the control unit begins to apply 1 MHz pulses to the input of the direct account +1 of the address of the charger. If, after supplying, for example, 15 pulses from the memory output, the unit was not read (a high level signal), the control unit switches the memory address counter to the countdown by sending pulses of 1 MHz frequency to its input 1. If after the input, 30 pulses will not be returned If the unit from the memory output is crushed, the control unit stops searching and, sending the corresponding command to the RO input, the signal sets the memory address counter to the zero state. This is not a typical case, since it can be only with a complete attenuation of the signal.

Consider the case when, for forward or backward, a unit is obtained from the output of the charger. The choice of the required 5 phases of the signal is made by the operator at the beginning of the measurement by entering

in the register of the current value of measurement in-. one . my code parameter corresponding to

five

0

the moment of fixation by the threshold device of this phase of the signal. The control unit at the moment of appearance at the output of the unit memory supplies input 5 of the sync pulse and a binary code corresponding to the instant of triggering the threshold device to the required signal phase, entering from the output address counter of the memory into register 5. That is, a new t parameter value. The control unit stops searching and sets the memory address counter to the zero state. The device is ready to determine the parameter t, which is produced in a similar way with the only difference that the recording of information into the memory address counter at the beginning of the search is performed from the outputs of the parameter register t, and the new value is recorded in the same register. To calculate the interval time At, a 10-bit binary adder is used, the inputs of which receive information from the register of the parameter t, in the inverse, and from the register of the parameter t in the forward code. At the same time, a 10-bit direct binary code of interval time D t is obtained at the input of the adder.

Information from the output of the register and the adder in the form of 10-bit binary codes is fed to external devices and to the inputs of digital-to-threshold converters, to the outputs of which external analog signal-recording devices can be connected.

The use of the device in comparison with other devices allows increasing the accuracy of determining the interval time and recording the kinematic parameters of not only longitudinal, but other types of waves.

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the invention

An acoustic logging device containing a threshold device, two registers of current measured values

parameters

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adder and three

A digital-to-analog converter, characterized in that, in order to improve the measurement accuracy,

. A memory device, a memory address counter, a control device and a switch are added to it, the signal from the downhole tool comes to one input of the threshold device, the other is connected to the corresponding output of the control device, the output of the threshold device is connected to the information input of the memory device.

5 devices, and the output is memory; device is connected to the input of the control device, to the other two inputs of which synchronization pulses are received from the downhole tool, the input

0 memory read / write control with the corresponding output of the control device, and the memory address inputs are connected to the counter outputs

5 addresses of the storage device and with the inputs of the registers, the inputs for controlling the recording of information in the registers are connected to the corresponding outputs of the control device, the counting inputs,

0, the inputs for setting the starting address and zeroing the counter of the memory address are connected to the corresponding outputs of the control device, and the information inputs of the initial setting of the memory address counter are connected to the switch outputs, the control inputs of the switch are connected to the corresponding outputs of the control device,

0 and the information inputs of the switch are connected to the outputs of the registers, the outputs of the registers are also connected to the inputs of the adder, with the parameter register 45

tj is connected directly, and the parameter register t inverse outputs with -. the corresponding inputs of the adder, the outputs of the registers and the adder are connected to the inputs of the corresponding digital-to-analog converters, while the outputs of the registers, the adder and digital-to-analog converters are the digital and analog outputs of the device.

Claims (1)

Claim Apparatus acoustic logging tool comprising a threshold device, two registers current values of measured variables t _4, t _2, an adder and three digital to analog converter, characterized in that, in order to increase the accuracy of measurements, ^y it is further administered a memory address counter of the memory device, the control device and the switch, while a signal from the downhole tool is received at one input of the threshold device, the other is connected to the corresponding output of the control device, the output of the threshold troystva connected to the data input of the memory and the output memory; the device is connected to the input of the control device, the two other inputs of which receive synchronization pulses from the downhole tool, the input of the write-read control of the storage device with the corresponding output of the control device, and the address inputs of the storage device are connected to the outputs of the counter of the address of the storage device and to the inputs of the registers, the inputs for controlling the recording of information in registers are connected to the corresponding outputs of the control device, counting inputs, inputs for setting the starting address and the zeroing of the memory address counter is connected to the corresponding outputs of the control device, and the information inputs of the initial installation of the memory address counter are connected to the outputs of the switch, the control inputs of the switch are connected to the corresponding outputs of the control device, and the information inputs of the switch are connected to the outputs of the registers, the outputs of the registers are also connected to adder inputs, and register the parameter t ₂ is connected to the direct and inverse outputs parameter register with a * ,? Resp adder inputs and outputs of the adder registers are connected to inputs of the corresponding digital to analog converters, the output registers, an adder and digital to analog converters are digital devices and analog outputs.