Large-caliber deep well logging instrument and measuring method thereof

Abstract

The invention discloses a large-caliber deep well logging instrument which comprises a cylindrical shell, a sound velocity measurement assembly, an ultrasonic distance measurement assembly, an orientation assembly and a data processing control module. A partition plate is arranged in the middle of an inner cavity of the cylindrical shell in the radial direction and divides the inner cavity of the cylindrical shell into an electronic cabin and a measuring cabin. The sound velocity measurement assembly is arranged at the top of the cylindrical shell and is used for measuring the sound velocity in the current water body; the orientation assembly and the data processing control module are arranged in the electronic cabin; the ultrasonic distance measuring assembly is arranged in the measuring cabin; the data processing control module performs data interaction with the sound velocity measurement assembly, the ultrasonic distance measurement assembly and the orientation assembly; the ultrasonic ranging assembly comprises a transducer and an electric control rotating mechanism; a rotating shaft of the electric control rotating mechanism is coaxial with a middle shaft of the cylindrical shell; the transducer is arranged in the electric control rotating mechanism and rotates along with the electric control rotating mechanism. The device can be suitable for high-precision measurement of the hole diameters of the large-diameter water wells with different depths and different water bodies.

Description

Technical Field

[0001] The invention relates to the technical field of well logging instruments, and in particular to a large-diameter deep-water well logging instrument and a measurement method thereof. Background Art

[0002] During large-diameter coal mine drilling, the actual horizontal cross-section of the wellbore varies with depth and is not a completely cylindrical shape. To ensure project quality, timely and accurate measurement and analysis of the wellbore's cross-sectional shape at different depths is crucial for evaluating well completion quality and adjusting drilling parameters.

[0003] There are many classic methods for distance measurement. Commonly used means for non-contact distance measurement include lasers, electromagnetic waves, and ultrasonic waves. However, when applied to the measurement of the shaft wall filled with turbid water, only ultrasonic waves can be used as a detection method. Ultrasonic shaft parameter measurement is a non-contact, indirect measurement method. It directly measures the time interval between the emission and reception of ultrasonic waves. The distance from the center to the shaft wall is calculated by multiplying the speed of sound by the time. The propagation characteristics of ultrasonic waves in turbid water media with high specific gravity are affected by many factors. Turbid water temperature, specific gravity, viscosity, sludge content, suspended particulate matter characteristics, etc. have a relatively large impact on the propagation characteristics of sound waves, so it is necessary to introduce correction units such as sound speed to ensure measurement accuracy.

[0004] like Figure 1 As shown, a traditional cylindrical ultrasonic logging tool has m ultrasonic transducers evenly distributed at an angle q on its bottom. It is suspended in the water and monitors distance in the direction corresponding to the transducers. The data measured by this logging tool is affected by the number of ultrasonic transducers arranged, resulting in too little data on a single horizontal section. The tool also lacks sound velocity correction, resulting in low accuracy. It lacks directional control, meaning the specific orientation of the ultrasonic transducers is unknown after lowering. It cannot achieve multi-angle measurements on the same horizontal plane with a single transducer, making it unsuitable for measuring large-diameter wells. Summary of the Invention

[0005] In response to the deficiencies in the prior art, the present invention provides a large-diameter deepwater well logging instrument and a measurement method thereof to solve the technical problems in the prior art of the logging instrument such as small amount of monitoring data on a single horizontal plane, low accuracy, lack of directional function and inapplicability to large-diameter deep wells.

[0006] The present invention provides a large-caliber deepwater well logging tool, comprising: a cylindrical shell, a sound velocity measurement component, an ultrasonic ranging component, a directional component, and a data processing control module;

[0007] A partition is radially provided in the middle of the inner cavity of the cylindrical shell, dividing the inner cavity of the cylindrical shell into an electronic compartment and a measurement compartment; a sound velocity measurement component is arranged at the top of the cylindrical shell, and is used to measure the current sound velocity in the water body; a direction-finding component and a data processing and control module are arranged in the electronic compartment, and the direction-finding component is used to obtain the current attitude data of the logging instrument, and the data processing and control module interacts with the sound velocity measurement component, ultrasonic ranging component and direction-finding component respectively; the ultrasonic ranging component is arranged in the measurement compartment;

[0008] The ultrasonic ranging component includes: a transducer and an electrically controlled rotating mechanism; the rotating axis of the electrically controlled rotating mechanism is coaxial with the central axis of the cylindrical shell; the transducer is arranged in the electrically controlled rotating mechanism and rotates with the electrically controlled rotating mechanism, and the transmitting end of the transducer faces the side wall of the cylindrical shell.

[0009] Furthermore, the sound velocity measurement assembly includes: a second transducer, a reflective plate and a bracket; the second transducer and the reflective plate are mounted on the top of the cylindrical housing through the bracket; the second transducer and the reflective plate are arranged opposite to each other.

[0010] Furthermore, the side walls of the measurement cabin are blue sound-transmitting windows.

[0011] Furthermore, the material of the blue sound-transmitting window is MC nylon material.

[0012] Furthermore, the directional component is a fiber optic gyroscope.

[0013] Furthermore, the ultrasonic ranging component also includes: a zero-point correction component; the zero-point correction component is used to calibrate the rotation angle of the electrically controlled rotating mechanism to zero.

[0014] Furthermore, the zero point correction component includes: an infrared transmitter and an infrared receiver; the infrared transmitter or infrared receiver is arranged on the electric-controlled rotating mechanism, and the infrared receiver or infrared transmitter is arranged on the inner wall of the measuring cabin, and the infrared transmitter and the infrared receiver are arranged opposite to each other.

[0015] Furthermore, the large-diameter deep-water well logging instrument further includes: a buffer component; the buffer component is arranged at the bottom of the cylindrical shell.

[0016] The present invention also provides a measurement method for a large-diameter deep-water well logging tool, which is applicable to the above-mentioned large-diameter deep-water well logging tool and comprises the following steps:

[0017] Step 1: Lower the logging tool to the desired measurement position and initialize the angle;

[0018] Step 2: Calculate the propagation rate of sound waves in the current water body;

[0019] Step 3: measuring the wellbore diameter in the current direction by ultrasonic wave, which includes correcting the sound velocity of the ultrasonic wave by the sound velocity calculated in step 2;

[0020] Step 4: Rotate the ultrasonic detection direction by a preset angle, and return to step 3 until the ultrasonic detection direction rotates one circle;

[0021] Step 5: Calculate the eccentric distance, well inclination azimuth and true radius based on all measured well diameters and corresponding measurement angles to complete the measurement.

[0022] Furthermore, in step 5, the calculation formula for the eccentric distance is:

[0023]

[0024] Where, R i is the measurement radius; θ i is the angle the transducer has rotated from the starting point; N is the number of measurements.

[0025] Furthermore, in step 5, the calculation formula for the well inclination is:

[0026]

[0027] Where, R i is the measurement radius; θ i is the angle the transducer has rotated from the starting point; N is the number of measurements.

[0028] Furthermore, in step 5, the calculation formula of the true radius is:

[0029]

[0030] Where R i is the measurement radius; N is the number of measurements.

[0031] Beneficial effects of the present invention:

[0032] The present invention can adapt to the high-precision measurement of the diameter of large-diameter water wells of different depths and different water bodies. The present invention only uses an ultrasonic ranging component and a transducer to measure the radius of large-diameter deep-water wells, which reduces the manufacturing cost while ensuring the original measurement function. The present invention obtains the sound propagation speed under the current water body through the sound velocity measurement component, which can effectively improve the accuracy of the transducer measurement results. The present invention adds a sound-transmitting window to the shell, which can reduce the loss of multiple sound waves as much as possible while maintaining the seal. The present invention uses a positioning component to obtain the posture of the device before measurement, which can provide accurate data for subsequent angle calibration and improve measurement accuracy. The present invention uses a zero-point correction component to determine the starting position during measurement and improve measurement accuracy. The measurement method of the present invention, in conjunction with the well logging instrument, can quickly and accurately obtain the eccentric distance, well inclination azimuth and true radius. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0034] Figure 1 is a schematic diagram of an existing logging tool;

[0035] Figure 2 is a schematic cross-sectional view of a well logging tool in a specific embodiment of the present invention;

[0036] Figure 3 is a schematic structural diagram of a sound velocity measurement assembly in a specific embodiment of the present invention;

[0037] Figure 4 is a schematic diagram of well logging in a specific embodiment of the present invention;

[0038] Figure 5 It is a schematic diagram of 1-meter range ring measurement in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0039] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0040] The present invention will be further described below with reference to specific examples. Those skilled in the art will appreciate that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention, and that modifications to various equivalent forms of the present invention fall within the scope defined by the appended claims.

[0041] like Figure 2 As shown, the present invention provides a large-caliber deepwater well logging tool, comprising: a cylindrical shell 1, a buffer component 2, a sound velocity measurement component 3, an ultrasonic ranging component, a directional component 5, and a data processing control module 6;

[0042] The cylindrical housing 1 is streamlined, with a flat cushioning element 2 at the bottom. This prevents the logging tool from getting stuck on uneven well walls, while also ensuring a stable base. Based on the hydrostatic pressure requirement of 1,000 meters and the pressure resistance requirement of 1.25 meters, the cylindrical housing must have an outer diameter of 150mm, a height of 800mm, and a wall thickness of 10mm. Furthermore, to ensure the logging tool can remain stable in deep water and quickly recover from rotation, the total weight must be greater than or equal to 30kg.

[0043] A partition 13 is radially provided in the middle of the inner cavity of the cylindrical shell 1 to divide the inner cavity of the cylindrical shell 1 into an electronic cabin 11 and a measurement cabin 12;

[0044] The orientation component 5 and the data processing control module 6 are arranged in the electronic cabin 11. The data processing control module 6 includes: a communication unit, a drive unit, an ADC conversion unit, a power amplification unit, a signal conditioning unit, a transceiver conversion unit and a processor. The data processing control module generates, receives and processes various signals through the above units to control the actions of various components in the entire measurement process and calculate the required measurement results based on the collected data. Since the cable will have uncontrollable rotation during the lowering of the logging instrument, it is necessary to orient it during the measurement process. The present invention uses the orientation component 5 to obtain the posture of the logging instrument. The orientation component 5 is preferably a fiber optic gyroscope to provide downhole orientation for the logging instrument and provide orientation data such as deflection angle and reference azimuth.

[0045] The ultrasonic ranging component is arranged in the measuring cabin 12, and the ultrasonic ranging component includes: a transducer 43, an electrically controlled rotating mechanism and a zero point correction component 44; the electrically controlled rotating mechanism includes: a motor 41 and a turntable 42; the rotating shaft of the motor 41 is connected to the center of the turntable 42, and the motor 41, the turntable 42 and the cylindrical shell 1 are coaxially arranged; the transducer 43 is arranged at the edge of the turntable 42 and rotates with the turntable 42, and the transmitting end of the transducer 43 faces the side wall of the cylindrical shell 1.

[0046] The transducer frequency affects the system's measurement range and error in media of varying specific gravities; the transducer bandwidth influences the system's measurement error and blind spots. A transducer utilizes a ceramic with a piezoelectric effect to generate mechanical vibrations and sound under voltage excitation. Transducers made from piezoelectric ceramics typically have a narrow frequency band, no more than 1 / 5 of the resonant frequency. This bandwidth is insufficient for high-precision distance measurement systems, especially for wellbore measurement in turbid water, where the presence of suspended particulate matter can result in high noise levels. The transducer utilizes a combined transmitter-receiver system, ensuring accurate distance measurement without being affected by pitch angle.

[0047] The theoretical measurement accuracy of the ranging system is related to the signal frequency. The higher the frequency, the higher the measurement accuracy and the smaller the error. The theoretical measurement accuracy is: λ / 4, where

[0048]

[0049] Where λ is the wavelength of the ultrasonic signal; c is the speed of sound; and f is the operating frequency.

[0050] When 600 kHz is used as the ultrasonic operating frequency, assuming that the sound velocity of turbid water is 1500 m / s, the corresponding wavelength is 2.5 mm, and the measurement accuracy is higher than 0.625 mm, meeting the maximum wellbore measurement error requirement.

[0051] When setting the blind zone of the transducer, 3 to 5 times the transducer diameter is usually taken as the estimated blind zone. Under the premise that the shell diameter needs to meet the pressure requirements of a thousand-meter deep-water well, the diameter of the transducer needs to be less than or equal to 30mm. If 3 times the diameter is selected as the blind zone estimation multiple, the diameter of the transducer needs to be less than or equal to 90mm. Combined with the impact of the transducer installation structure on the blind zone, it is finally necessary to consider that the blind zone of the transducer needs to be less than or equal to 150mm.

[0052] The ultrasonic beam is related to the transducer diameter and the operating frequency of the ultrasound. Reducing the beam helps increase the number of effective points on the measurement circumference. Controlling the signal system bandwidth ensures good distance resolution of the measurement system. In terms of acoustic power, the sonar system is a linear system, and nonlinear phenomena during acoustic wave transmission must be avoided as much as possible. Nonlinear effects can cause waveform distortion, transfer acoustic wave energy to other frequency components, and accelerate acoustic energy attenuation, resulting in a decrease in effective range. Therefore, the acoustic power cannot be too high, that is, the sound source level cannot be too high. In summary, the transducer operating frequency is preferably set to 600kHz, the bandwidth is preferably set to 200kHz, and the diameter is preferably set to 30mm. This corresponds to a ranging error of 0.625mm, a spatial resolution of 3.75mm, and a beam angle of ±2.4°.

[0053] The motor uses a two-phase hybrid stepper motor. There is no need to subdivide the step distance during rough measurement, and 200 data can be output on the circumference of the hole wall. The step distance needs to be subdivided during fine measurement, which can achieve a smaller step angle and encrypt the data in the circumferential direction. For example, it is subdivided into about 1.4 degrees per step, 256 steps are taken within 360 degrees, and 256 data are obtained.

[0054] The zero-point calibration assembly 44 includes an infrared transmitter and an infrared receiver. The infrared transmitter is mounted on a turntable, and the infrared receiver is mounted on the inner wall of the measurement chamber, with the infrared transmitter and the infrared receiver positioned opposite each other. The logging tool rotates during lowering, and the turntable rotates freely even when the transducer is not operating. When the transducer needs to operate, the zero-point calibration assembly rotates the transducer via a motor until the zero-point calibration assembly is successfully calibrated, thereby initializing the transducer's position.

[0055] The sidewalls of the measurement chamber 12 are blue acoustically transparent windows 122 made of MC nylon. According to acoustic window energy attenuation testing, at the same transmission power and propagation distance, the same 600kHz broadband transducer placed in the acoustically transparent window attenuates the acoustic signal by approximately 3dB compared to receiving the sound signal directly without the window. This minimal attenuation meets design requirements. Therefore, the acoustically transparent window can effectively replace the metal wall of the cylindrical shell, reducing the attenuation of sound waves by the sidewalls of the measurement chamber 12 while providing effective sealing and strength. Silicone oil can also be injected into the measurement chamber 12.

[0056] like Figure 3 As shown, the sound velocity measurement component is arranged on the top of the cylindrical shell, and the sound velocity measurement component is used to measure the sound velocity in the current water body;

[0057] The sound velocity measurement assembly 3 includes a second transducer 31, a reflector 32, and a bracket 33. The bracket 33 is U-shaped and hollow, and is mounted on the top of the cylindrical housing 1. The second transducer 31 is positioned on the inner side of one side of the bracket 33; the reflector 32 is positioned on the inner side of the other side of the bracket 33. The second transducer 31 and the reflector 32 are positioned opposite each other. The spacing between the second transducer 31 and the reflector 32 is predetermined, i.e., the span of the U-shaped bracket 33. The second transducer 31 can be used to measure the propagation velocity of sound waves in the water between the second transducer 31 and the reflector 32. This velocity reflects the propagation velocity of the sound waves generated by the transducer in the current water body, providing an accurate sound velocity for subsequent wellbore measurements.

[0058] A specific embodiment of the present invention further provides a measurement method for a large-diameter deep-water well logging tool, which is applicable to the above-mentioned large-diameter deep-water well logging tool and includes the following steps:

[0059] Step 1: Lower the logging tool to the desired measurement position, obtain the current posture of the logging tool through the positioning component, and adjust the posture; at the same time, initialize the angle through the zero point calibration component to put the transducer in the initial position;

[0060] Step 2: Calculate the propagation speed of the sound wave in the current water body through the sound velocity measurement component;

[0061] Step 3: Use the transducer to measure the wellbore diameter in the current direction. The measured wellbore diameter is:

[0062]

[0063] Where c0 is the average speed of sound waves in the medium; T i is the time taken for the sound wave to propagate back and forth, where the average sound speed is calculated using the sound speed measured in step 2;

[0064] Step 4: Control the stepper motor to rotate the detection direction of the transducer at a preset angle, and return to step 3 until the detection direction of the transducer rotates one circle;

[0065] Step 5: Calculate the eccentric distance, well inclination azimuth and true radius based on all measured well diameters and corresponding measurement angles to complete the measurement.

[0066] like Figure 4 As shown, point O is the location of the geometric center of the transducer; O' is the true center of the wellbore; θ i is the heading angle of the current direction of the transducer, with due north as the initial direction of the transducer, θ i is the angle between the sound wave direction and the true north direction; R i is the measured distance from the well wall to the transducer, and r is the true radius.

[0067] By the cosine theorem we can get:

[0068] R i 2 +S 2 -2R i Scos(α i )=r 2

[0069] Where S is the eccentricity, a i is the well inclination, N is the number of measurements;

[0070] in,

[0071] After the formula transformation:

[0072]

[0073] like Figure 5 As shown in the figure, the circular measurement results of a specific embodiment of the present invention in a simulated environment are shown. In the figure, the blue area is the area circle with a radius of 1m generated by the software to be measured; the center point of the longitude and latitude lines is the center of the designed well circle, and the point close to it is the center point during measurement; the white coil is the measured well circumference curve; the colored area outside the white line coil is the high and low energy areas caused by the energy attenuation of the ultrasonic measurement.

[0074] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A large-caliber deepwater well logging tool, characterized in that: include: Cylindrical shell, sound velocity measurement component, ultrasonic ranging component, directional component and data processing control module; A partition is radially provided in the middle of the inner cavity of the cylindrical shell, dividing the inner cavity of the cylindrical shell into an electronic compartment and a measurement compartment. A sound velocity measurement component is arranged at the top of the cylindrical shell and is used to measure the current sound velocity in the water body. A direction finding component and a data processing and control module are arranged in the electronic compartment. The direction finding component is used to obtain the current attitude data of the logging instrument. The data processing and control module interacts with the sound velocity measurement component, ultrasonic ranging component and direction finding component data respectively. The ultrasonic ranging component is arranged in the measuring cabin; The ultrasonic ranging component includes: a transducer and an electrically controlled rotating mechanism; the rotating axis of the electrically controlled rotating mechanism is coaxial with the central axis of the cylindrical shell; the transducer is arranged in the electrically controlled rotating mechanism and rotates with the electrically controlled rotating mechanism, and the transmitting end of the transducer faces the side wall of the cylindrical shell.

2. The large-diameter deepwater well logging tool according to claim 1, characterized in that: The sound velocity measurement assembly includes: a second transducer, a reflector and a bracket; the second transducer and the reflector are mounted on the top of the cylindrical housing through the bracket; the second transducer and the reflector are arranged opposite to each other.

3. The large-diameter deepwater well logging tool according to claim 1, characterized in that: The side walls of the measuring cabin are blue sound-transmitting windows.

4. The large-diameter deepwater well logging tool according to claim 3, characterized in that: The material of the blue sound-transmitting window is MC nylon.

5. The large-diameter deepwater well logging tool according to claim 1, characterized in that: The directional component is: a fiber optic gyroscope.

6. The large-diameter deepwater well logging tool according to claim 1, characterized in that: The ultrasonic distance measurement component also includes: a zero point correction component; the zero point correction component is used to calibrate the rotation angle of the electric control rotation mechanism to zero.

7. The large-diameter deepwater well logging tool according to claim 6, characterized in that: The zero point correction component includes: an infrared transmitter and an infrared receiver; the infrared transmitter or infrared receiver is arranged on the electric control rotating mechanism, the infrared receiver or infrared transmitter is arranged on the inner wall of the measuring cabin, and the infrared transmitter and the infrared receiver are arranged opposite to each other.

8. A measurement method applicable to a large-diameter deepwater well logging tool as claimed in any one of claims 1 to 7, characterized in that: The steps include: Step 1: Lower the logging tool to the desired measurement position and initialize the angle; Step 2: Calculate the propagation rate of sound waves in the current water body; Step 3: measuring the wellbore diameter in the current direction by ultrasonic wave, which includes correcting the sound velocity of the ultrasonic wave by the sound velocity calculated in step 2; Step 4: Rotate the ultrasonic detection direction by a preset angle, and return to step 3 until the ultrasonic detection direction rotates one circle; Step 5: Calculate the eccentric distance, well inclination azimuth and true radius based on all measured well diameters and corresponding measurement angles to complete the measurement.

9. The measurement method of a large-diameter deepwater well logging tool according to claim 8, characterized in that: In step 5, the calculation formula of the eccentric distance is: The calculation formula for well inclination is: Where, R i is the measurement radius; θ i is the angle the transducer has rotated from the starting point; N is the number of measurements.

10. The measurement method of a large-diameter deepwater well logging tool according to claim 8 or 9, characterized in that: In step 5, the calculation formula of the true radius is: Where R i is the measurement radius; N is the number of measurements.

Images