A calibration device and method for a borehole television imager

Abstract

A calibration device and method for a borehole television imager. The device includes a rotary table, an inclination table, a calibration barrel support, a calibration barrel, a gyroscope, a control box and a laptop computer; the lower end of the inclination table is fixed to the upper end of the rotary table; the lower end of the calibration barrel support is fixed to the upper end of the inclination table, and the upper end of the calibration barrel support is fixed with a calibration barrel; the gyroscope is installed at the bottom of the calibration barrel support; the control box is electrically connected to the rotary table, the inclination table, the gyroscope and the laptop computer respectively. The calibration device and method for the borehole television imager provided by the present invention have the following beneficial effects: the calibration device has a high degree of systematic integration, realizes the calibration functions of the inclination angle, azimuth angle, line width resolution and line width indication error of the borehole television imager, and there is no need to repeatedly disassemble and connect test equipment during the test process, which is easy to implement and has good application effects and popularization value.

Description

Technical Field

[0001] The present invention belongs to the technical field of metrological calibration for traffic and water transportation engineering, and particularly relates to a calibration device and method for a borehole television imager. Background Art

[0002] Pile foundations are a common type of deep foundation and are widely used in the field of water transportation engineering. They are the main load-bearing parts of hydraulic building structures, and their quality is directly related to the applicability, safety, and durability of the structure. However, pile foundations are hidden works, and professional testing methods must be used to evaluate and determine their quality. Currently, pile shaft testing methods include static load test method, acoustic wave transmission method, core drilling method, high strain method, low strain method, etc. There are disputes in the test data of current various testing methods, and the core drilling method is the most effective verification method. Borehole television imagers are commonly used for core drilling verification, and can be used to observe the positions and degrees of defects such as cavities, fissures, and segregation in concrete, observe various anomalies and defects inside prestressed pipe piles, check the joint conditions, and quantitatively analyze the quality of the pile shaft. However, changes in the working environment over a long time and the aging of the instrument itself will cause changes in the metrological performance of the instrument, resulting in large deviations in the measurement results. Therefore, it is particularly important to calibrate the metrological performance of the borehole television imager regularly. Currently, there is no relevant technical report in China on a dedicated calibration device for borehole television imagers. If an uncalibrated borehole television imager is used in pile shaft testing, it will surely bring great potential safety hazards to the project. Summary of the Invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a calibration device and method for a borehole television imager.

[0004] To achieve the above purpose, the calibration device for a borehole television imager provided by the present invention includes a rotating table, an inclined table, a calibration barrel support, a calibration barrel, a gyroscope, a control box, and a laptop computer; wherein, the lower end of the inclined table is fixed to the upper end of the rotating table; the lower end of the calibration barrel support is fixed to the upper end of the inclined table, and the upper end of the calibration barrel support is fixed with a calibration barrel; the gyroscope is installed at the bottom of the calibration barrel support; the control box is electrically connected to the rotating table, the inclined table, the gyroscope, and the laptop computer respectively; the borehole television imager to be measured includes a borehole television imager main unit and a borehole television imager probe connected to each other, and the borehole television imager probe is fixed to the calibration barrel.

[0005] The rotating table includes a rotation control motor, a rotating disk, a rotating table base, a first worm gear, a first worm shaft, and a first coupling; wherein the rotating table base is a box body with an open upper end; the rotation control motor is installed on the outer side surface of the rotating table base, and its output shaft passes through the side surface of the rotating table base and is connected to one end of the first worm shaft through the first coupling; the rotating disk is rotatably installed on the inner bottom surface of the rotating table base, and a first worm gear is provided on its circumferential surface; the first worm shaft meshes with the first worm gear.

[0006] The tilting table includes a tilt control motor, a tilt slider, a tilting table base, a second worm gear, a second worm shaft, a second coupling, and an arc-shaped ball guide rail; wherein the tilting table base is fixed to the rotating disk of the rotating table; the tilt control motor is installed in the middle of the outer side surface of the tilting table base, and its output shaft passes through the side surface of the tilting table base and is connected to one end of the second worm shaft through the second coupling; two arc-shaped ball guide rails are installed on both sides of the second worm shaft in parallel; the top surface of the tilt slider is installed with a calibration barrel support, the bottom surface is arc-shaped, and both sides of the bottom surface are respectively installed on the two arc-shaped ball guide rails, a second worm gear is provided in the middle of the bottom surface, and the second worm gear meshes with the first worm gear.

[0007] The calibration barrel includes a probe clamp, a screw, a support frame, a round barrel, and a line width calibration plate; wherein, the lower end of the support frame is fixed to the upper end of the calibration barrel support; the bottom surface of the round barrel is closed, and an opening is formed on the circumferential surface and the top surface respectively, and the middle of the bottom surface is fixed to the upper end of the support frame; the lower end of the probe clamp is fixed to the outer side of the opening on the top surface of the round barrel for clamping the borehole television imager probe and fastening it with a screw; the lower end of the borehole television imager probe is inserted into the inside of the round barrel through the opening on the top surface of the round barrel; the line width calibration plate is attached to the inner circumferential surface of the round barrel, and a plurality of vertical scale lines with different widths and line width standard values are spaced on its surface.

[0008] The method for calibrating a borehole television imager using the borehole television imager calibration device according to the claims includes the following steps carried out in sequence:

[0009] 1) Connect the components of the borehole television imager calibration device in sequence, vertically fix the borehole television imager probe on the probe clamp, power on and preheat the borehole television imager calibration device, initialize the serial port, and zero the rotating table and the tilting table under the control of a laptop computer; power on and turn on the borehole television imager main unit, and perform parameter settings so that both the dip indication value and the trend indication value are zero.

[0010] 2) Attach the line width calibration plate to the inner circumferential surface of the round barrel from the opening on the circumferential surface of the round barrel, adjust the position of the line width calibration plate so that the borehole television imager main unit can clearly display the image of the line width calibration plate, and observe that the line width indication value of the thinnest vertical scale line on the line width calibration plate that can be recognized in the image is the line width resolution.

[0011] 3) Take each vertical scale line on the line width calibration plate as a line width calibration point. Use the main unit of the borehole television imager to sequentially read the line width indication values at each line width calibration point on the line width calibration plate from thick to thin. Then, calculate the line width indication error according to Equation (1) in combination with the line width standard value, and take the maximum value of the absolute values of the line width indication errors at all line width calibration points as the calibration result of the line width indication error;

[0012] ΔL i =L i -L i0 (1)

[0013] In the formula:

[0014] ΔL i —— The line width indication error of the main unit of the measured borehole television imager at each line width calibration point, mm;

[0015] L i —— The line width indication value of the main unit of the measured borehole television imager at each line width calibration point, mm;

[0016] L i0 —— The line width standard value, mm;

[0017] 4) Select -180°, -135°, -90°, -45°, 0°, 45°, 90°, 135° and 180° as the azimuth calibration points. Use the laptop to control the rotary table to rotate to each of the above azimuth calibration points in turn, respectively read and record the dip indication values of the main unit of the borehole television imager at each calibration point, and calculate the azimuth indication error according to Equation (2) in combination with the dip standard reference value measured by the gyroscope. Take the maximum value of the absolute values of the azimuth indication errors at all azimuth calibration points as the calibration result of the azimuth indication error;

[0018] Δθ i =θ i -θ i0 (2)

[0019] In the formula:

[0020] Δθ i —— The azimuth indication error of the main unit of the measured borehole television imager at each azimuth calibration point, °;

[0021] θ i —— The dip indication value of the main unit of the measured borehole television imager at each azimuth calibration point, °;

[0022] θ i0 —— The dip standard reference value measured by the gyroscope, °;

[0023] 5) Select -30°, -20°, 10°, 0°, 10°, 20° and 30° as the inclination calibration points. Use a laptop to control the tilt table to tilt to each of the above inclination calibration points in turn. Read and record the inclination indication values at each inclination calibration point displayed by the borehole television imager host. Calculate the inclination indication error according to Equation (3) in combination with the standard reference value of the inclination measured by the gyroscope. Take the maximum value of the absolute values of the inclination indication errors at all inclination calibration points as the calibration result of the inclination indication error;

[0024] Δλ i =λ i -λ i0 (3)

[0025] In the formula:

[0026] Δλ i —— The inclination indication error of the host of the measured borehole television imager at each inclination calibration point, °;

[0027] λ i —— The inclination indication value of the host of the measured borehole television imager at each inclination calibration point, °;

[0028] λ i0 —— The standard reference value of the inclination measured by the gyroscope, °.

[0029] The borehole television imager calibration device and method provided by the present invention have the following beneficial effects: The calibration device has a high degree of systematic integration, realizing the calibration functions of the inclination angle, azimuth angle, line width resolution and line width indication error of the borehole television imager. During the test process, there is no need to repeatedly disassemble and connect the test equipment, which is easy to implement and has good application effects and popularization value. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of the borehole television imager calibration device provided by the present invention;

[0031] Figure 2 It is a schematic diagram of the rotary table in the borehole television imager calibration device provided by the present invention;

[0032] Figure 3 It is a schematic diagram of the tilt table in the borehole television imager calibration device provided by the present invention;

[0033] Figure 4 It is a schematic structural diagram of the calibration barrel in the borehole television imager calibration device provided by the present invention.

[0034] Figure 5 It is a block diagram of the composition of the borehole television imager calibration device provided by the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0035] The calibration device and method for a borehole television imager provided by the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0037] As Figure 1 、 Figure 5 shown, the calibration device for a borehole television imager provided by the present invention includes a rotating table 10, an inclined table 20, a calibration barrel bracket 30, a calibration barrel 40, a gyroscope 50, a control box 60, and a laptop computer 70; wherein, the lower end of the inclined table 20 is fixed to the upper end of the rotating table 10; the lower end of the calibration barrel bracket 30 is fixed to the upper end of the inclined table 20, and the upper end of the calibration barrel bracket 30 is fixed with a calibration barrel 40; the gyroscope 50 is installed at the bottom of the calibration barrel bracket 30; the control box 60 is electrically connected to the rotating table 10, the inclined table 20, the gyroscope 50, and the laptop computer 70 respectively; the borehole television imager to be measured includes a borehole television imager main unit 80 and a borehole television imager probe 90 which are connected to each other, and the borehole television imager probe 90 is fixed to the calibration barrel 40.

[0038] As Figure 2 shown, the rotating table 10 includes a rotation control motor 101, a rotating disk 102, a rotating table base 103, a first worm gear 104, a first worm 105, and a first coupling 106; wherein the rotating table base 103 is a box body with an open upper end; the rotation control motor 101 is installed on the outer side surface of the rotating table base 103, and the output shaft passes through the side surface of the rotating table base 103 and is connected to one end of the first worm 105 through the first coupling 106; the rotating disk 102 is rotatably installed on the inner bottom surface of the rotating table base 103, and a first worm gear 104 is provided on the circumferential surface; the first worm 105 meshes with the first worm gear 104; the control box 60 issues an instruction to make the rotation control motor 101 rotate, thereby driving the first coupling 101 and the first worm 105 to rotate synchronously, and then the first worm 105 drives the first worm gear 104 to rotate, and finally the rotating disk 102 makes a rotational movement.

[0039] As Figure 3As shown in the figure, the tilting table 20 includes a tilt control motor 201, a tilt slider 202, a tilting table base 203, a second worm gear 204, a second worm 205, a second coupling 206, and an arc-shaped ball guide 207. The tilting table base 203 is fixed on the rotating disk 102 of the rotating table 10. The tilt control motor 201 is installed in the middle of the outer side of the tilting table base 203. After the output shaft penetrates the side of the tilting table base 203, it is connected to one end of the second worm 205 through the second coupling 206. Two arc-shaped ball guides 207 are installed on both sides of the second worm 205 in a parallel manner. The top surface of the tilt slider 202 is installed with a calibration barrel bracket 30, and the bottom surface is arc-shaped. The two sides of the bottom surface are respectively installed on the two arc-shaped ball guides 207. The middle of the bottom surface is provided with a second worm gear 204, and the second worm gear 204 meshes with the first worm gear 104. The control box 60 issues an instruction to rotate the tilt control motor 201, thereby driving the second coupling 206 and the second worm 205 to rotate synchronously. Then, the second worm 205 drives the second worm gear 204 to rotate, and finally the tilt slider 202 tilts along the arc-shaped ball guide 207.

[0040] As Figure 4 shown, the calibration barrel 40 includes a probe clamp 601, a screw 602, a support frame 603, a round barrel 604, and a line width calibration plate 605. The lower end of the support frame 603 is fixed to the upper end of the calibration barrel bracket 30. The bottom surface of the round barrel 604 is closed, and an opening is formed on the circumferential surface and the top surface respectively. The middle of the bottom surface is fixed to the upper end of the support frame 603. The lower end of the probe clamp 601 is fixed to the outer side of the opening on the top surface of the round barrel 604 for clamping the borehole television imaging probe 90 and fastening it with the screw 602. The lower end of the borehole television imaging probe 90 is inserted into the inside of the round barrel 604 through the opening on the top surface of the round barrel 604. The line width calibration plate 605 is attached to the inner circumferential surface of the round barrel 604, and a plurality of vertical scale lines with different widths and line width standard values are arranged at intervals on the surface.

[0041] The inclination measurement accuracy of the gyroscope 70 is better than 0.01°, and the inclination stability is better than 0.06° / h.

[0042] The tilt measurement range of the borehole television imaging probe calibration device provided by the present invention is ±35°, the tilt measurement accuracy is better than 0.01°, the inclination measurement range is ±180°, the inclination measurement accuracy is better than 0.1°, the line width measurement range is 0.02 - 10 mm, and the maximum allowable error of the line width is ±0.005 mm.

[0043] Now, the working principle of the borehole television imaging probe calibration device provided by the present invention is described as follows:

[0044] During operation, connect the probe 90 of the borehole television imager to the main unit 80 of the borehole television imager. Use the probe fixture 601 on the calibration barrel 40 to clamp the middle part of the probe 90 of the borehole television imager and tighten the screw 602, and make the probe 90 of the borehole television imager perpendicular to the ground. At the same time, insert the lower end of the probe 90 of the borehole television imager into the inside of the barrel 604 through the opening on the top surface of the barrel 604. Connect the control box 60 to the gyroscope 50, the rotating table 10, the tilting table 20 and the laptop computer 70. Turn on the main unit 80 of the borehole television imager and perform a zero setting so that the inclination angle and dip indication values of the probe 90 of the borehole television imager are both 0°. Power on the control box 60, turn on the laptop computer 70, and control the rotating table 10 and the tilting table 20 to return to the zero position. Read the line width indication value of the vertical scale line on the line width calibration plate 605 displayed on the main unit 80 of the borehole television imager, and compare it with the line width standard value of the vertical scale line on the line width calibration plate 605 to obtain the line width indication error. Observe that the line width indication value of the thinnest vertical scale line on the line width calibration plate 605 displayed on the main unit 80 of the borehole television imager is the line width resolution. Control the rotation of the rotating table 10 and the tilting of the tilting table 20 by a certain angle value through the laptop computer 70 to simulate the dip and inclination angle of the pile foundation borehole respectively. Take the dip value and inclination angle value measured by the gyroscope 50 as the standard reference values, and compare the inclination indication value and dip indication value displayed on the main unit 80 of the borehole television imager with the dip and azimuth standard reference values measured by the gyroscope 50 respectively to obtain the inclination indication error and azimuth indication error.

[0045] The method for calibrating a borehole television imager using the above-mentioned borehole television imager calibration device includes the following steps carried out in sequence:

[0046] 1) Connect the components of the borehole television imager calibration device in sequence, vertically fix the probe 90 of the borehole television imager on the probe fixture 601, power on and preheat the borehole television imager calibration device, initialize the serial port, and control the rotating table 10 and the tilting table 20 to return to the zero position by the laptop computer 70; power on and turn on the main unit 80 of the borehole television imager, and perform parameter settings so that the inclination indication value and dip indication value are both zero;

[0047] 2) Attach the line width calibration plate 605 to the inner circumferential surface of the barrel 604 through the opening on the circumferential surface of the barrel 604, adjust the position of the line width calibration plate 605 so that the main unit 80 of the borehole television imager can clearly display the image of the line width calibration plate 605, and observe that the line width indication value of the thinnest vertical scale line on the recognizable line width calibration plate 605 in the image is the line width resolution;

[0048] 3) Take each vertical scale line on the line width calibration plate 605 as a line width calibration point. Use the host 80 of the borehole television imager to sequentially read the line width indication values at each line width calibration point on the line width calibration plate 605 from thick to thin. Then, calculate the line width indication error according to Equation (1) in combination with the line width standard value. Take the maximum value of the absolute values of the line width indication errors at all line width calibration points as the calibration result of the line width indication error;

[0049] ΔL i =L i -L i0 (1)

[0050] In the formula:

[0051] ΔL i —— The line width indication error of the host 80 of the measured borehole television imager at each line width calibration point, mm;

[0052] L i —— The line width indication value of the host 80 of the measured borehole television imager at each line width calibration point, mm;

[0053] L i0 —— The line width standard value, mm;

[0054] 4) Select -180°, -135°, -90°, -45°, 0°, 45°, 90°, 135° and 180° as the azimuth calibration points. Use the laptop 70 to control the rotary table 10 to rotate to each of the above azimuth calibration points in turn. Read and record the dip indication values of the host 80 of the borehole television imager at each calibration point respectively. Calculate the azimuth indication error according to Equation (2) in combination with the dip standard reference value measured by the gyroscope 50. Take the maximum value of the absolute values of the azimuth indication errors at all azimuth calibration points as the calibration result of the azimuth indication error;

[0055] Δθ i =θ i -θ i0 (2)

[0056] In the formula:

[0057] Δθ i —— The azimuth indication error of the host 80 of the measured borehole television imager at each azimuth calibration point, °;

[0058] θ i —— The dip indication value of the host 80 of the measured borehole television imager at each azimuth calibration point, °;

[0059] θ i0 —— The dip standard reference value measured by the gyroscope 50, °;

[0060] 5) Select -30°, -20°, 10°, 0°, 10°, 20° and 30° as the inclination calibration points. Use the laptop 70 to control the tilt table 20 to tilt to each of the above inclination calibration points in turn. Read and record the inclination indication values at each inclination calibration point displayed by the borehole television imager host 80. Calculate the inclination indication error according to Equation (3) by combining the standard reference value of the inclination measured by the gyroscope 50. Take the maximum value of the absolute values of the inclination indication errors at all inclination calibration points as the calibration result of the inclination indication error;

[0061] Δλ i =λ i -λ i0 (3)

[0062] In the formula:

[0063] Δλ i —— The inclination indication error of the measured borehole television imager host 80 at each inclination calibration point, °;

[0064] λ i —— The inclination indication value of the measured borehole television imager host 80 at each inclination calibration point, °;

[0065] λ i0 —— The standard reference value of the inclination measured by the gyroscope 50, °.

Claims

1. A calibration device for a borehole television imager, characterized in that: The calibration device for the borehole television imager includes a rotary table (10), an inclination table (20), a calibration barrel support (30), a calibration barrel (40), a gyroscope (50), a control box (60), and a laptop computer (70); wherein, the lower end of the inclination table (20) is fixed to the upper end of the rotary table (10); the lower end of the calibration barrel support (30) is fixed to the upper end of the inclination table (20), and the upper end of the calibration barrel support (30) is fixed with a calibration barrel (40); the gyroscope (50) is installed at the bottom of the calibration barrel support (30); the control box (60) is electrically connected to the rotary table (10), the inclination table (20), the gyroscope (50), and the laptop computer (70); the borehole television imager to be measured includes a borehole television imager main unit (80) and a borehole television imager probe (90) connected to each other, wherein the borehole television imager probe (90) is fixed to the calibration barrel (40). The rotary table (10) includes a rotation control motor (101), a rotating disk (102), and a rotary table base (103); wherein the rotary table base (103) is a box body with an open upper end. The inclination table (20) includes an inclination control motor (201); the inclination table base (203) is fixed to the rotating disk (102) of the rotary table (10). The calibration barrel (40) includes a probe fixture (601), screws (602), a support frame (603), a cylindrical barrel (604), and a line width calibration plate (605); wherein, the lower end of the support frame (603) is fixed to the upper end of the calibration barrel support (30); the bottom surface of the cylindrical barrel (604) is closed, and an opening is formed on each of the circumferential surface and the top surface, and the middle of the bottom surface is fixed to the upper end of the support frame (603); the lower end of the probe fixture (601) is fixed to the outer side of the opening on the top surface of the cylindrical barrel (604) for clamping the borehole television imager probe (90) and fastening it with screws (602); the lower end of the borehole television imager probe (90) is inserted into the inside of the cylindrical barrel (604) through the opening on the top surface of the cylindrical barrel (604); the line width calibration plate (605) is attached to the inner circumferential surface of the cylindrical barrel (604), and a plurality of vertical scale lines with different widths and line width standard values are provided at intervals on the surface.

2. The calibration device for borehole television imager according to claim 1, characterized in that: The rotary table (10) further includes a first worm gear (104), a first worm (105), and a first coupling (106); the rotation control motor (101) is installed on the outer side surface of the rotary table base (103), and the output shaft passes through the side surface of the rotary table base (103) and is connected to one end of the first worm (105) through the first coupling (106); the rotating disk (102) is rotatably installed on the inner bottom surface of the rotary table base (103), and a first worm gear (104) is provided on the circumferential surface; the first worm (105) meshes with the first worm gear (104).

3. The borehole television imager calibration device according to claim 2, characterized in that: The tilting table (20) further includes a tilting slider (202), a tilting table base (203), a second worm gear (204), a second worm (205), a second coupling (206) and an arc-shaped ball guide rail (207); the tilting control motor (201) is installed in the middle of the outer side of the tilting table base (203), and the output shaft passes through the side of the tilting table base (203) and is connected to one end of the second worm (205) through the second coupling (206); two arc-shaped ball guide rails (207) are installed on both sides of the second worm (205) in a parallel manner; the top surface of the tilting slider (202) is installed with a calibration bucket bracket (30), the bottom surface is arc-shaped, and both sides of the bottom surface are respectively installed on the two arc-shaped ball guide rails (207), the middle of the bottom surface is provided with a second worm gear (204), and the second worm gear (204) meshes with the first worm gear (104).

4. A method for calibrating a borehole televiewer using the borehole televiewer calibration device according to any one of claims 1 to 3, characterized in that: The method includes the following steps carried out in sequence: 1) Connect the components of the borehole television imager calibration device in sequence, vertically fix the borehole television imager probe (90) on the probe fixture (601), power on and preheat the borehole television imager calibration device, initialize the serial port, and zero the rotary table (10) and the tilting table (20) under the control of the laptop computer (70); power on and turn on the borehole television imager host (80), and perform parameter settings so that both the dip indication value and the trend indication value are zero; 2) Attach the line width calibration plate (605) to the inner circumferential surface of the drum (604) from the opening on the circumferential surface of the drum (604), adjust the position of the line width calibration plate (605) so that the borehole television imager host (80) can clearly display the image of the line width calibration plate (605), and observe that the line width indication value of the thinnest vertical scale line on the recognizable line width calibration plate (605) in the image is the line width resolution; 3) Take each vertical scale line on the line width calibration plate (605) as a line width calibration point, use the borehole television imager host (80) to sequentially read the line width indication values at each line width calibration point on the line width calibration plate (605) from thick to thin, and then calculate the line width indication error according to Equation (1) in combination with the line width standard value, and take the maximum value of the absolute values of the line width indication errors at all line width calibration points as the calibration result of the line width indication error; ΔL i = L i - L i0 (1) In the formula: ΔL i ——Indicated line width error of the host (80) of the borehole television imager to be measured at each line width calibration point, mm; L i —— Indicated line width of the host (80) of the borehole television imager under test at each line width calibration point, mm; L i0 —— Standard line width value, mm; 4) Select -180°, -135°, -90°, -45°, 0°, 45°, 90°, 135° and 180° as the azimuth calibration points, use the laptop computer (70) to control the rotary table (10) to rotate to each of the above azimuth calibration points in sequence, respectively read and record the trend indication values at each calibration point displayed by the borehole television imager host (80), calculate the azimuth indication error according to Equation (2) in combination with the trend standard reference value measured by the gyroscope (50), and take the maximum value of the absolute values of the azimuth indication errors at all azimuth calibration points as the calibration result of the azimuth indication error; Δθ i = θ i - θ i0 (2) In the formula: Δθ i —— Azimuth indication error of the main body (80) of the borehole television imager under test at each azimuth calibration point, °; θ i ——Indicated dip value of the host (80) of the borehole televiewer to be measured at each azimuth calibration point, °; θ i0 —— Standard reference value of inclination measured by gyroscope 50, °; 5) Select -30°, -20°, 10°, 0°, 10°, 20° and 30° as the inclination calibration points. Use a laptop computer (70) to control the tilt table (20) to tilt to each of the above inclination calibration points in turn, read and record the inclination indication values at each inclination calibration point displayed by the borehole television imager host (80), and calculate the inclination indication error according to Equation (3) in combination with the standard reference value of the inclination measured by the gyroscope (50). Take the maximum value of the absolute values of the inclination indication errors at all inclination calibration points as the calibration result of the inclination indication error; Δλ i = λ i - λ i0 (3) In the formula: Δλ i —— The inclination indication error of the main body (80) of the borehole television imager to be measured at each inclination calibration point, °; λ i —— The inclination indication value of the main unit (80) of the borehole television imager to be measured at each inclination calibration point, °; λ i0 —— Standard reference value of the inclination angle measured by the gyroscope (50), °.

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