Novel method for correcting eccentricity of multi-arm hole diameter logging information of horizontal well
The spatial distribution of the array arm was determined by monitoring the response of the forty-arm well diameter logger and the probe azimuth angle. A correction model considering the vertical and horizontal offset of the horizontal wellbore array logger was established, and the horizontal well multi-arm well diameter logging was solved. The problem of data eccentricity affects the accuracy of the multi-arm well logging data and high-precision evaluation, providing effective support for damage monitoring and repair of oil and gas wells.
Patent Information
- Application Number
- CN202411519959.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2024-12-13
AI Technical Summary
The horizontal well multi-arm well diameter logging data are prone to eccentricity during the measurement process, resulting in large errors in measuring curve distortion and casing damage evaluation. The existing calibration methods cannot effectively eliminate a variety of influencing factors, resulting in amplification of errors or leakage.
The spatial distribution of the array arm is determined by monitoring the response of the forty-arm well diameter logger and azimuth angle of the probe. A method for spatial reset eccentricity correction of instrument centers that considers the vertical and horizontal offset of the horizontal wellbore array logger and symmetrical arm response differences are established. Correction model under different conditions, finely correcting multi-arm well logging data.
Accurate correction of the eccentricity effect of the multi-arm well diameter logging data of horizontal wells is achieved, which weakens the eccentricity effect of instruments, improves the accuracy of oil casing damage monitoring and evaluation, provides more accurate judgment of damage location and level, and is complete to the wellbore Sexual repair provides technical support.
Smart Images
Figure CN119122505A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a new method for correcting the eccentricity of multi-arm caliper logging data in horizontal wells, which is mainly aimed at accurately correcting the eccentricity of forty-arm caliper logging data in horizontal wells. Based on the monitoring response of the forty-arm caliper logging instrument and the probe azimuth, the spatial distribution of the array arms is determined, and an eccentricity correction method for resetting the center space of the instrument is established by considering the vertical and horizontal offsets of the horizontal wellbore array logging instrument and the response differences of the symmetrical arms. The method effectively reduces the eccentricity of the monitoring response of the multi-arm caliper logging instrument in the intact and damaged states of the horizontal well oil casing, and is an accurate and reliable method for correcting the eccentricity of multi-arm caliper logging data in horizontal wells. Background Art
[0002] Accurately monitoring and locating the location of casing (oil) pipe damage in horizontal wells with casing completion, evaluating the damage status and damage level of oil (casing) pipes, is extremely important for guiding the evaluation of the sealing of horizontal oil and gas wells and guiding the repair of damaged casing (oil) pipes. At present, the commonly used direct oil casing damage detection technologies mainly include multi-arm caliper logging technology and electromagnetic induction detection technology. Multi-arm caliper logging technology has been widely used in oil fields due to its intuitive, rapid and economical advantages. The commonly used multi-arm caliper logging instruments are divided into different structures such as 24 arms, 40 arms, 60 arms, and 120 arms. The 40-arm caliper logging instrument is the most commonly used in the field. During the multi-arm caliper logging process of horizontal wells, affected by the wellbore structure of the horizontal well and the weight of the instrument itself, the instrument will be eccentric during the measurement process, and the multi-arm caliper monitoring curve of the horizontal well section will be significantly distorted. The error in the evaluation of casing (oil) pipe damage in the horizontal well is very large, which can easily lead to misjudgment of the location and damage level of the oil casing.
[0003] At present, the main methods for correcting the eccentricity of multi-arm caliper logging data in horizontal wells include side compensation method, wall thickness difference method, circular fitting algorithm, ellipse fitting algorithm, mass center method and chord fitting method. The side compensation method can correct wells with a well inclination angle less than 45°. When the well inclination is greater than 45°, the sum of its absolute sides cannot reflect the true wellbore information due to the excessive eccentricity of the instrument, resulting in the illusion of elliptical deformation of the casing. The wall thickness difference method uses the difference between the maximum value to calculate the remaining wall thickness. In the measurement of inclined wells, its absolute error will be magnified due to the eccentricity of the instrument. The circular fitting algorithm, ellipse fitting algorithm and chord fitting method can easily miss the situation of local damage to the casing by equivalently fitting the wellbore curve obtained by instrument monitoring. The mass center method is relatively simple to calculate, but it cannot display the specific location of the wellbore and is prone to missing the damaged part of the casing. Therefore, it is necessary to establish a high-precision eccentricity correction method based on the structural characteristics of oil casing in horizontal wells.
[0004] The present invention is based on the monitoring data of forty-arm caliper logging instruments. By considering the vertical and horizontal offsets of horizontal wellbore array logging instruments and the differences in symmetric arm response values, different correction models are established for the vertical and horizontal eccentricity of the instrument, and the conditions of intact and damaged casing. A new eccentricity correction method for multi-arm caliper logging data of horizontal wells is proposed, which realizes the accurate correction of the eccentricity effect of multi-arm caliper logging data under different conditions, and provides effective technical support for the monitoring and evaluation of damage, damage location and repair of oil casing in horizontal wells. Summary of the invention
[0005] The purpose of the present invention is to provide a new method for eccentricity correction of multi-arm caliper logging data of horizontal wells, thereby obtaining a corrected multi-arm caliper logging response value, which can accurately reflect the structural characteristics and damage location of the oil casing of the horizontal oil and gas well, effectively support the high-precision evaluation of the multi-arm caliper monitoring data, and further provide support for the integrity repair of the oil and gas well bore.
[0006] In order to achieve the above technical objectives, the present invention provides the following technical solutions.
[0007] Assume that the actual wellbore value monitored by the forty-arm caliper logging tool is L i (i is the clockwise measurement arm number of the multi-arm wellbore, i = 1, 2, 3, ..., 40), the rotation azimuth of arm No. 1 is ROT 1 The angle between any two adjacent arms of the 40-arm caliper logging tool is 9°, and the center point of the eccentric instrument is the origin of the rectangular coordinate system corresponding to (0, 0).
[0008] (1) When there is any arm located exactly in the north direction of the wellbore section, the corresponding arm number is,
[0009]
[0010] When the non-existent arm is located at the top of the wellbore, the instrument arm number closest to the top is,
[0011] when hour,
[0012]
[0013] when hour,
[0014]
[0015] The maximum offset distance of the symmetrical arm is,
[0016]
[0017] The coordinates of the center point of the wellbore section are expressed as (0, Δmax).
[0018] In the formula, [] is a rounding operation; NO is the arm number at the top arm; ROT 1 is the azimuth of arm 1 obtained by monitoring the multi-arm caliper logging tool, °; Δmax is the maximum offset distance, mm; L i is the measured well diameter value, mm.
[0019] Finally, the calibration is completed based on the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinate point (0, Δmax) of the center circle of the wellbore section.
[0020] (2) When there is no damage to the casing
[0021] When the vertical and horizontal offset occurs, the maximum offset direction of the instrument is determined by subtracting the difference between the symmetrical arms. The maximum offset distance of the symmetrical arms is:
[0022]
[0023] Then the maximum offset arm azimuth is,
[0024] When L i ≥L i+20 hour,
[0025]
[0026] Then the coordinates of the center point of the wellbore section (x 0 ,y 0 ) is expressed as,
[0027] When ROT m ≤180,
[0028] When ROT m >180, When L i <L i+20 hour,
[0029]
[0030] Then the coordinates of the center point of the wellbore section (x 0 ,y 0 ) is expressed as,
[0031] When ROT m ≤180,
[0032] When ROT m >180,
[0033] Where Δmax is the maximum offset distance, mm; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured well diameter of arm i+20, mm; ROT 1 is the azimuth of arm 1 obtained by monitoring the multi-arm caliper logging tool, °; ROT m The azimuth angle of the longest arm to be substituted when calculating the offset azimuth, °; L m It is the measured well diameter value that replaces the longest arm when calculating the offset azimuth, mm; ROT i is the azimuth angle of the i-th arm monitored by the multi-arm caliper logging tool, °; x 0 The horizontal coordinate value of the center point of the wellbore section, y 0 The vertical coordinate value of the center point of the wellbore section.
[0034] Finally, according to the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinate point (x 0 ,y 0 ) Complete the eccentricity correction.
[0035] (3) When the casing is damaged
[0036] When the wellbore is damaged, two methods are used to calculate the coordinates of the center point of the wellbore section, and then the average value of the coordinates of the center points of the two sections is taken.
[0037] Method 1: find the difference of the casing symmetry arms and then sort the differences.
[0038]
[0039] If the sorted Δ i According to the arm numbers of multi-arm wellbore diameters, the arm number with the largest difference decreases symmetrically. If the decreasing difference is relatively uniform, there is no casing damage. When the position of a certain arm number is reversed and the decreasing difference is abnormal, the arm number position is damaged.
[0040] The maximum offset direction of the instrument is determined by sorting the difference between the symmetrical arms. The maximum offset distance of the symmetrical arms is:
[0041]
[0042] Δ i-1 ≤Δmax=Δm=Δ i ≥Δ i+1 ,i=2,3,···,19 (14)
[0043] The casing damage position is determined based on the difference in the casing symmetrical arms. When the serial number position of a certain arm is reversed and the decreasing difference is abnormal, damage occurs at the serial number position of that arm.
[0044] The maximum offset direction of the instrument is determined by subtracting the difference between the symmetrical arms. The maximum offset distance of the symmetrical arms is:
[0045]
[0046] Then the maximum offset arm azimuth is,
[0047] When L i ≥L i+20 hour,
[0048]
[0049] Then the coordinates of the center point of the wellbore section (x 0 ,y 0 ) is expressed as,
[0050] When ROT m ≤180,
[0051] When ROT m >180, When L i <L i+20 hour,
[0052]
[0053] Then the coordinates of the center point of the wellbore section (x 0 ,y 0 ) is expressed as,
[0054] When ROT m ≤180,
[0055] When ROT m >180,
[0056] Where Δmax is the maximum offset distance, mm; Sort is the difference sorting function; Δi is the offset distance between the i-th arm and the symmetric arm, mm; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured well diameter of arm i+20, mm; ROT 1 is the azimuth of arm 1 obtained by monitoring the multi-arm caliper logging tool, °; ROT m The azimuth angle of the longest arm to be substituted when calculating the offset azimuth, °; L mIt is the measured well diameter value that replaces the longest arm when calculating the offset azimuth, mm; ROT i is the azimuth angle of the i-th arm monitored by the multi-arm caliper logging tool, °; x 0 The horizontal coordinate value of the center point of the wellbore section, y 0 The vertical coordinate value of the center point of the wellbore section.
[0057] Method 2: The rotation angle of arm 1 is known to be ROT 1 The angle between any two adjacent arms is always 9°. The wall thickness difference of two pairs of arms perpendicular to each other is used to calculate the corresponding offset distance, and the coordinates of the center point of the wellbore section (x 0 ',y 0 '). It is known that the rotation angle of arm 1 is ROT 1 , the angle between any two adjacent arms is always 9°, and the arm number of the top arm is,
[0058]
[0059] Taking the i-th arm as the maximum offset distance, the coordinates of the center point of the wellbore section (x 0 ',y 0 '),
[0060]
[0061] The coordinate position of the center point of the final wellbore section can be expressed as
[0062]
[0063] Where NO is the arm number of the top arm; ROT 1 is the azimuth of arm 1 obtained by monitoring the multi-arm caliper logging tool, °; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured well diameter of arm i+20, mm; (x 0 ',y 0 ') The coordinates of the center point of the wellbore section obtained using two arms perpendicular to each other; (x 0 ,y 0 ) are the coordinates of the center point of the wellbore section obtained using two arms perpendicular to each other; The final coordinates of the center point of the wellbore section are obtained by averaging the coordinates obtained by method one and method two.
[0064] Finally, according to the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinate point of the center circle of the wellbore section Complete the eccentricity correction.
[0065] Compared with the prior art, the present invention has the following significant advantages: (1) It effectively eliminates the influence of various factors. Compared with the traditional casing damage evaluation method, the present invention takes into account various influencing factors such as well inclination, instrument deadweight, casing damage type, etc., and comprehensively analyzes and intuitively displays the damage and deformation of the oil casing; (2) The evaluation accuracy is high. By combining the original casing damage evaluation method, it is less affected by eccentricity, and its measurement results can reflect the real wellbore information with a small error; (3) It is highly operational. The casing damage evaluation method adopted by the present invention is applicable to situations with or without casing damage, and has strong application operability and is easy to implement. (4) Data acquisition is relatively convenient, and it can also provide supporting parameters for the later repair of damaged wells. BRIEF DESCRIPTION OF THE DRAWINGS
[0066] Figure 1 This is a schematic diagram of the instrument only experiencing vertical eccentricity.
[0067] Figure 2 Schematic diagram of the instrument experiencing axial and horizontal eccentricity (no damage).
[0068] Figure 3 Schematic diagram of the instrument experiencing axial and horizontal eccentricity (damage).
[0069] Figure 4 This is a comparison chart of the data before and after eccentricity correction and the actual inner diameter of the casing (3470m).
[0070] Figure 5 This is the error analysis diagram of the eccentricity correction method.
[0071] Figure 6 This is the eccentricity correction effect diagram of the multi-arm caliper logging data of the F1 horizontal well (3750-3850m). DETAILED DESCRIPTION
[0072] Figure 1 This is a schematic diagram of the instrument only experiencing vertical eccentricity.
[0073] Figure 2 This is a schematic diagram of the axial and horizontal eccentricity of the instrument (without damage). Based on this diagram, the center coordinates of the wellbore section are solved when the casing is not damaged.
[0074] Figure 3 This is a schematic diagram of the axial and horizontal eccentricity of the instrument (damage). Based on this diagram, the center coordinates of the wellbore section with damaged casing are solved.
[0075] Figure 4 This is a comparison chart of the data before and after eccentricity correction and the actual inner diameter of the casing (3470m).
[0076] Figure 5 This is the error analysis diagram of the eccentricity correction method.
[0077] Figure 6 This is the eccentricity correction effect diagram of the multi-arm caliper logging data of the F1 horizontal well (3750-3850m).
[0078] Application examples:
[0079] Well F1 is a production well in northwest China, with an altitude of 400.78m and a core filling height of 9.59m. The well was designed to be drilled at the T1b21 layer, with a vertical depth and an inclined depth of 2703.43m and 4347.76m respectively. The actual drilling layer was T1b21, with a vertical depth and an inclined depth of 2697.62m and 4178m respectively. The well was started on November 25, 2019, and completed on July 17, 2020. The well was completed on the 25th. The vertical depth and inclined depth of the inclination point were 2299.72m and 2300m respectively, the horizontal section was 1436m long, the vertical depth and inclined depth of target point A were 2607.78m and 2742m respectively, the vertical depth and inclined depth of target point B were 2697.62m and 4178m respectively, the artificial well bottom was 4144.53m, the standard outer diameter of the F1 well oil layer casing was 139.7mm, and the standard inner diameter was 129.16mm. The specific casing data are shown in Table 1.
[0080] Table 1F1 Well Casing Data Table
[0081]
[0082] In September 2024, multi-arm caliper logging was carried out. The original data analysis showed that there was obvious eccentricity in the horizontal section of the well from 2742 to 4178 m. Based on the eccentricity correction method of multi-arm caliper logging data of horizontal wells established by the present invention, the F1 well was corrected for eccentricity. Among them, the data before and after eccentricity correction at a depth of 3470 m were compared with the actual inner diameter of the casing. Figure 4 As shown in Figure 2, the eccentricity-corrected data matches the actual wellbore inner diameter well, with a relative error distribution range of -0.53-0.66% ( Figure 5 ).
[0083] Based on the method of the present invention, the eccentricity correction processing of the multi-arm caliper logging data of the entire F1 well section is completed, and the eccentricity correction result of the 3750-3850m section is shown in the figure. Figure 6As shown, from left to right, the first track in the figure is the depth track of the logging curve; the second track is the wellbore information, including well inclination angle, well temperature, and ellipticity; the third track is the MIT wellbore characteristic curve, including current wall thickness, original wall thickness, maximum radius, minimum radius, and average radius; the fourth track is the original multi-arm wellbore caliper curve 2D map for correction; the fifth track is the original multi-arm wellbore caliper curve 3D map without correction; the sixth track is the multi-arm wellbore caliper curve 2D map after correction; the seventh track is the multi-arm wellbore caliper curve 3D map after correction. The comparison of the effects before and after correction shows that the wellbore data corrected by the horizontal well multi-arm wellbore caliper logging data eccentricity correction method established by the present invention effectively eliminates the influence of instrument eccentricity in the horizontal wellbore, and can be further used for wellbore casing damage judgment and analysis.
Claims
1. A new method for eccentricity correction of multi-arm caliper logging data in horizontal wells, thereby obtaining the corrected multi-arm caliper logging response value. When the casing is not damaged and the instrument only deviates vertically, it is assumed that the actual wellbore value monitored by the 40-arm caliper logging instrument is L i (i is the clockwise measurement arm number of the multi-arm caliper, i = 1, 2, 3, ..., 40), the rotation azimuth of arm 1 is ROT1, the angle between any two adjacent arms of the 40-arm caliper logging instrument is 9°, the center point of the eccentric instrument is the corresponding coordinate origin (0, 0) of the rectangular coordinate system, when any arm is located exactly in the north direction of the wellbore section, the corresponding arm number is, When the non-existent arm is located at the top of the wellbore, the instrument arm number closest to the top is, when hour, when hour, The maximum offset distance of the symmetrical arm is, Then the coordinates of the center point of the wellbore section are expressed as (0, Δmax), Where, Δmax is the maximum offset distance, mm; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured wellbore diameter of the i+20th arm, mm; ROT1 is the azimuth of the No. 1 arm monitored by the multi-arm caliper logging instrument, °; ROT m The azimuth angle of the longest arm to be substituted when calculating the offset azimuth, °; L m It is the measured well diameter value that replaces the longest arm when calculating the offset azimuth, mm; ROT i is the azimuth angle of the i-th arm monitored by the multi-arm caliper logging instrument, °; x0 is the horizontal coordinate value of the center point of the wellbore section, y0 is the vertical coordinate value of the center point of the wellbore section; finally, the correction is completed based on the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinates of the center point of the wellbore section (0, Δmax).
2. According to claim 1, the casing is not damaged and only has vertical offset eccentricity. The casing is not damaged and the instrument has horizontal and vertical offset eccentricity. The maximum offset direction of the instrument is determined by subtracting the difference between the symmetrical arms. The maximum offset distance of the symmetrical arms is, Then the maximum offset arm azimuth is, When L i ≥L i+20 hour, Then the coordinates of the center point of the wellbore section (x0, y0) are expressed as: When ROT m ≤180, When ROT m >180, When L i <L i+20 hour, Then the coordinates of the center point of the wellbore section (x0, y0) are expressed as: When ROT m ≤180, When ROT m >180, Where Δmax is the maximum offset distance, mm; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured wellbore diameter of the i+20th arm, mm; ROT1 is the azimuth of the No. 1 arm monitored by the multi-arm caliper logging instrument, °; ROT m The azimuth angle of the longest arm to be substituted when calculating the offset azimuth, °; L m It is the measured well diameter value that replaces the longest arm when calculating the offset azimuth, mm; ROT i is the azimuth angle of the i-th arm monitored by the multi-arm caliper logging instrument, °; x0 is the horizontal coordinate value of the center point of the wellbore section, and y0 is the vertical coordinate value of the center point of the wellbore section; finally, the eccentricity correction is completed according to the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinates of the center point of the wellbore section (x0, y0).
3. According to the eccentricity of the instrument with vertical and horizontal deviations in the case of no damage to the casing as described in claim 2, the case of damage to the casing and eccentricity of the instrument with horizontal and vertical deviations is extended to the case of damage to the casing and eccentricity of the instrument with horizontal and vertical deviations. The coordinates are averaged after the eccentricity is calculated using two methods. Method 1 calculates the difference of the symmetric arms of the casing and then sorts the difference. If the sorted Δ i According to the arm number of the multi-arm wellbore, the arm number with the largest difference decreases symmetrically. If the decreasing difference is relatively uniform, there is no casing damage. When the position of a certain arm number is reversed and the decreasing difference is abnormal, the position of the arm number is damaged. The maximum offset direction of the instrument is determined by sorting the symmetrical arm difference. The maximum offset distance of the symmetrical arm is, D i-1 ≤Δmax=Δm=Δ i ≥D i+1 ,i=2,3,···,19(14) The casing damage position is determined by the difference of the casing symmetrical arms. When the serial number position of a certain arm is reversed and the decreasing difference is abnormal, the serial number position of the arm is damaged. The maximum offset direction of the instrument is determined by subtracting the difference of the symmetrical arms. The maximum offset distance of the symmetrical arm is, Then the maximum offset arm azimuth is, When L i ≥L i+20 hour, Then the coordinates of the center point of the wellbore section (x0, y0) are expressed as: When ROT m ≤180, When ROT m >180, When L i <L i+20 hour, Then the coordinates of the center point of the wellbore section (x0, y0) are expressed as: When ROT m ≤180, When ROT m >180, Method 2: The rotation azimuth of arm 1 is known to be ROT1, and the angle between any two adjacent arms is always 9°. The wall thickness difference of two pairs of arms perpendicular to each other is used to calculate the corresponding offset distance, and the coordinates of the center point of the wellbore section (x0', y0') are obtained. The rotation azimuth of arm 1 is known to be ROT1, and the angle between any two adjacent arms is always 9°. The arm number of the top arm is, Taking the i-th arm as the maximum offset distance, the coordinates of the center point of the wellbore section (x0', y0') are obtained. The coordinate position of the center point of the final wellbore section can be expressed as Where Δmax is the maximum offset distance, mm; Sort is the difference sorting function; Δi is the offset distance between the i-th arm and the symmetric arm, mm; L i is the measured well diameter value of arm No. i, mm; L i+20 is the measured wellbore diameter of the i+20th arm, mm; ROT1 is the azimuth of the No. 1 arm monitored by the multi-arm caliper logging instrument, °; ROT m The azimuth angle of the longest arm to be substituted when calculating the offset azimuth, °; L m It is the measured well diameter value that replaces the longest arm when calculating the offset azimuth, mm; ROT i is the azimuth of the i-th arm monitored by the multi-arm caliper logging instrument, °; NO is the arm number at the top arm; (x0', y0') is the coordinate of the center point of the wellbore section obtained by using two arms perpendicular to each other; (x0, y0) is the coordinate of the center point of the wellbore section obtained by using two arms perpendicular to each other; The final coordinates of the center point of the wellbore section are obtained by averaging the coordinates obtained by method 1 and method 2; finally, the coordinate point (0, 0) corresponding to the center point of the eccentric instrument and the coordinates of the center point of the wellbore section are calculated. Complete the eccentricity correction.