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Abstract

The present disclosure provides a passive passive while-drilling borehole detection method, device and computer storage medium, belonging to the technical field of logging while drilling, the device comprises: at least one sensor for acquiring the induced magnetic signal corresponding to the magnetic field generated by the target well; azimuth reference unit for acquiring real-time attitude angle data of the drilling tool in the rotation process; processing unit, respectively, and the sensor and the azimuth reference unit are connected, for synchronously acquiring the induced magnetic signal and the real-time attitude angle data; according to the real-time attitude angle data, the multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to obtain the comprehensive signal strength corresponding to each azimuth interval, the rotation space of the drilling tool is divided into multiple azimuth intervals; and, according to the distribution characteristics of the comprehensive signal strength corresponding to multiple azimuth intervals, the azimuth and distance information of the target well relative to the drilling tool are determined. It can realize accurate positioning of the target well in the process of continuous rotation of the drilling tool.

Description

Technical Field

[0001] This disclosure relates to the field of logging while drilling technology, and in particular to a passive, passive wellbore detection method, device, and computer storage medium. Background Technology

[0002] During oil and gas field development, the drilling scale of cluster wells, infill wells, sidetracking of old wells, and rescue wells continues to expand. Wellbore collision prevention is a core aspect of ensuring drilling operation safety and avoiding casing damage and wellbore abandonment. While-drilling collision prevention ranging technology can monitor the relative positions of adjacent wells in real time during drilling and is a core technical means of wellbore collision prevention. Among them, passive passive while-drilling ranging technology does not require an excitation device to be inserted downhole into the target well or to actively emit magnetic field signals; it only needs to collect the magnetic field generated by the magnetization of the target well casing in the Earth's magnetic field to achieve ranging.

[0003] However, the magnetic field signal generated by the casing of the target well is extremely weak and attenuates rapidly and nonlinearly with increasing spatial distance, resulting in an extremely weak effective magnetic signal reaching the sensor through the formation. Furthermore, under actual measurement-while-drilling conditions, the continuous rotation and vibration of the drilling tools will generate dynamic interference, which will severely contaminate the already weak useful magnetic signal, thus leading to inaccurate positioning of the target well based on the detected magnetic signal. Summary of the Invention

[0004] This disclosure provides a passive, passive wellbore detection method, device, and computer storage medium; it enables precise positioning of the target well during the continuous rotation of the drilling tool.

[0005] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides a passive, passive drilling detection device for use in drilling tools. The device is disposed within the pressure chamber of the drilling tool and includes: At least one sensor is used to acquire an induced magnetic signal corresponding to the magnetic field generated by the target well. The sensor includes a first receiving magnetic core and a first induction coil arranged along the axial direction of the drilling tool. The induced magnetic signal includes a first induced magnetic signal corresponding to the magnetic field in the axial direction. An orientation reference unit is used to acquire real-time attitude angle data of the drilling tool during rotation. The processing unit, communicatively connected to both the sensor and the orientation reference unit, is configured to: synchronously acquire induced magnetic signals and real-time attitude angle data; and, Based on real-time attitude angle data, multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to obtain the comprehensive signal intensity corresponding to each azimuth interval. The rotation space of the drilling tool is divided into multiple azimuth intervals; and, Based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals, the azimuth and distance information of the target well relative to the drilling tool are determined.

[0006] Secondly, this disclosure provides a passive, passive drilling-while-drilling wellbore detection method, the method comprising: Simultaneously acquire the induced magnetic signal corresponding to the magnetic field generated by the target well and the real-time attitude angle data of the drilling tool. The induced magnetic signal includes the first induced magnetic signal of the magnetic field in the axial direction. Based on real-time attitude angle data, multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to generate comprehensive signal intensity corresponding to each azimuth interval, and the rotation space of the drilling tool is divided into multiple azimuth intervals. Based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals, the azimuth and distance information of the target well relative to the drilling tool are determined.

[0007] Thirdly, this disclosure provides a computer-readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the passive, passive drilling detection method as described in the second aspect.

[0008] Fourthly, this disclosure provides a computer program product, wherein the computer program product includes a computer program or instructions, which, when run on a processor, cause the processor to execute the computer program or instructions to implement the steps of the passive passive drilling detection method as described in the second aspect.

[0009] Fifthly, this disclosure provides a chip including a processor and a communication interface coupled to the processor, the processor being used to run programs or instructions to implement the passive passive drilling detection method as described in the second aspect. Attached Figure Description

[0010] Figure 1 This is a schematic diagram illustrating an application scenario of a passive, passive wellbore detection device provided in this disclosure.

[0011] Figure 2 This is a schematic diagram of the structure of a passive, passive drilling detection device provided in this disclosure.

[0012] Figure 3 This is a cross-sectional schematic diagram showing the relative position of the sensor provided in this disclosure within the pressure chamber of the drill collar.

[0013] Figure 4 This is a schematic diagram of the structure of the first receiving magnetic core and the first induction coil provided in this disclosure.

[0014] Figure 5This is a schematic diagram of the comprehensive signal strength corresponding to each directional interval provided in this disclosure.

[0015] Figure 6 This is a schematic diagram showing the positional arrangement of the multiple receiving magnetic cores and induction coils provided in this disclosure.

[0016] Figure 7 This is a flowchart illustrating a passive, passive wellbore detection method provided in this disclosure. Detailed Implementation

[0017] The technical solutions in the embodiments of this disclosure will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure are within the scope of protection of this disclosure.

[0018] The terms “first,” “second,” etc., used in this disclosure are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that this disclosure can be implemented in orders other than those illustrated or described herein, and the objects distinguished by “first,” “second,” etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more.

[0019] refer to Figure 1 This is a schematic diagram illustrating an application scenario of the passive, passive drilling detection device provided in this embodiment of the present disclosure. Figure 1 The components and their corresponding numbers included are: target well 10, casing of the target well 101, new wellbore 11, drilling tools 20, drilling tools 20 including: drill collar 201, drill bit 202 and drill pipe 203, support assembly 12, winch 13, surface monitoring system 14, and passive passive drilling wellbore detection device 30 provided in this disclosure.

[0020] During cluster well anti-collision, infill drilling, or rescue well connection operations, a target well 10 with completed drilling and cementing already exists in the formation. A casing 101 made of ferromagnetic material (such as carbon steel) is installed inside the target well 10. Because the casing 101 is made of ferromagnetic material, it will be continuously magnetized in the Earth's background magnetic field over a long period of time, thereby radiating a stable magnetic field outward in the wellbore space of the target well 10.

[0021] In the vicinity of the target well 10, a new wellbore 11 is being drilled using drilling tool 20. Drilling tool 20, from top to bottom, comprises: drill pipe 203, drill collar 201, and drill bit 202, all components rigidly connected by a special thread. The central axes of drilling tool 20, drill pipe 203, drill collar 201, and drill bit 202 are collinear.

[0022] The drill pipe 203 consists of multiple interconnected pipes. Its upper end connects to the power system of the surface drilling rig (not shown in the figure), and its lower end connects to the drill collar 201. It transmits the rotational torque and axial load of the drilling rig downhole, while its hollow interior forms a high-pressure circulation path for drilling fluid, providing a carrier for signal transmission from downhole to the surface. The drill collar 201 is connected in series between the drill pipe 203 and the drill bit 202, applying stable and uniform drilling pressure to the drill bit 202 by its own weight. The drill bit 202 is installed at the bottom of the drilling tool 20 and, as it rotates synchronously with the drilling rig, breaks up the formation rock, enabling the drilling of the new wellbore 11. The drilling tool 20 is made of a non-magnetic alloy material, such as high-chromium-nitrogen austenitic stainless steel non-magnetic drill collar material like P550, P580, or P750. This avoids the situation where the drilling tool 20 forms an extremely strong Faraday magnetic shield due to the high magnetic permeability of ordinary steel, which would completely shield the very weak induced magnetic signal radiated by the target well 10 from the outside of the bulkhead.

[0023] The support assembly 12 is a load-bearing structure for drilling operations and may include a drilling rig and a matching pulley block. The winch 13 lowers, raises, and controls the suspension weight of the drilling tool 20 by winding the drilling connection rope through the pulley block of the support assembly 12.

[0024] The passive passive drilling wellbore detection device 30 provided in this embodiment is integrated and installed in the pressure chamber of the drilling tool 20, specifically in the pressure chamber of the drill collar 201 or the drill pipe 203. Since the drill collar 201 is close to the drill bit 202, the passive passive drilling wellbore detection device 30 is installed in the pressure chamber of the drill collar 201, which can make the detection position as close as possible to the drilling front edge, so as to reduce the detection error caused by the wellbore trajectory delay. Therefore, the following description takes the passive passive drilling wellbore detection device 30 integrated in the pressure chamber of the drill collar 201 as an example.

[0025] The passive passive drilling wellbore detection device 30 refers to a downhole instrument that does not contain an active alternating current emission source and achieves positioning by passively picking up the external environmental magnetic field. It is configured to determine the orientation and distance information of the casing 101 relative to the new wellbore 11 in real time during the rotation of the drilling collar 201, and then upload the information to the surface monitoring system 14 in real time via wired or wireless communication.

[0026] The ground monitoring system 14 compares and analyzes the received azimuth and distance information with the preset trajectory design data of the new wellbore 11. When the distance between the target well 10 and the new wellbore 11 is detected to be less than the anti-collision safety threshold, the drilling trajectory is adjusted to avoid a collision between the new wellbore 11 and the casing 101.

[0027] Specifically, in the embodiments of this disclosure, such as Figure 2As shown, the passive passive drilling borehole detection device 30 includes: at least one sensor 301 (two are shown in the figure), an azimuth reference unit 302, and a processing unit 303 that is communicatively connected to the sensor 301 and the azimuth reference unit 302, respectively. At least one sensor 301, the azimuth reference unit 302, and the processing unit 303 are all sealed and integrated inside the pressure chamber of the drill collar 201, and the pressure chamber is made of a non-magnetic alloy material.

[0028] Sensor 301 is used to acquire the induced magnetic signal corresponding to the magnetic field radiated by the casing 101 of the target well after it has been magnetized by the geomagnetic field. Sensor 301 includes a first receiving magnetic core and a first induction coil arranged along the axial direction of the drilling tool. Accordingly, the induced magnetic signal includes a first induced magnetic signal of the magnetic field in the axial direction.

[0029] The induced magnetic signal refers to the analog electrical signal output at both ends of the induction coil, characterizing the rate of change of magnetic flux, after the magnetic field radiated by the casing 101 of the target well 10 is focused by the sensor 301 through the high-permeability magnetic core. This magnetic flux changes periodically as the drilling tool 20 rotates. The first induced magnetic signal refers to the induced magnetic signal corresponding to the axial component of the magnetic field radiated by the casing 101, extracted along the axial direction parallel to the central axis of the drilling tool 20.

[0030] After being magnetized in the Earth's background magnetic field, the casing 101 radiates a weak, low-frequency magnetic field with a magnetic field strength of only one ten-thousandth to one hundred-thousandth of the Earth's magnetic field. Moreover, the magnetic field strength decreases dramatically by approximately a cubic factor as the distance from the detection point increases. Conventional hollow coils cannot effectively capture the effective signal corresponding to the weak, low-frequency magnetic field radiated by the casing 101 in the context of strong interference such as electromagnetic interference from downhole drilling equipment and vibration noise from drilling tools.

[0031] This disclosure includes a first receiving magnetic core, with its long axis arranged along the axial direction of the drilling tool 20. The long axis of the first receiving magnetic core is approximately parallel to the magnetic field lines radiated by the casing 101, allowing as many magnetic field lines as possible to pass through the first receiving magnetic core, thereby increasing the magnetic flux. Figure 3 The diagram shows a cross-sectional view of the relative position of sensor 301 within the pressure chamber of drill collar 201, as exemplarily shown. The dotted areas represent the pressure chamber between the outer and inner walls of the drill collar. The vertical dashed line represents the central axis 304 of drill collar 201, which is also the central axis of drilling tool 20. The central axis 305 of the axially arranged sensor 301 is parallel to the central axis 304. The solid lines with arrows represent magnetic lines of force generated by the magnetic field. The magnetic lines of force pass through sensor 301, thereby generating a first induced magnetic signal.

[0032] The first receiving magnetic core is configured with a permeability greater than a preset threshold (the preset threshold is not less than 1000, which is much greater than the relative permeability of air). Based on the low magnetic resistance of the magnetic field to the high permeability material, the first receiving magnetic core can concentrate the weak low-frequency magnetic field that was originally dispersed in the surrounding space, so that the magnetic field lines are concentrated and constrained inside the first receiving magnetic core, thereby increasing the magnetic flux passing through the effective cross section of the first receiving magnetic core and amplifying and enhancing the weak low-frequency magnetic field of the target well 10.

[0033] During the synchronous rotation of the first receiving magnetic core driven by the drilling tool 20, the magnetic flux passing through the first receiving magnetic core periodically alternates with the change in the orientation of the first receiving magnetic core, forming an enhanced alternating magnetic flux. The first induction coil wound on the first receiving magnetic core converts this enhanced alternating magnetic flux into a first induced magnetic signal carried by voltage, based on Faraday's law of electromagnetic induction. The first induced magnetic signal is typically a low-frequency AC voltage signal in the microvolt to millivolt range, and its variation period is synchronized with the rotation period of the drilling tool 20.

[0034] Meanwhile, to improve detection sensitivity within the limited internal space of the pressure chamber of the drilling tool 20, the thickness of the first receiving magnetic core is determined based on a preset magnetic field enhancement model. The magnetic field enhancement model characterizes the detection sensitivity. Relative permeability with the first receiving magnetic core The effective cross-sectional area of ​​the first receiving magnetic core Positively correlated with, and also with, the thickness of the first receiving magnetic core. Negative correlation, its derivation formula can be characterized as: .like Figure 4 The diagram shows the structure of the first receiving magnetic core 3011 and the first induction coil 3012. The thickness d refers to the tangential length of the first receiving magnetic core in the drill collar 201.

[0035] Based on the aforementioned nonlinear relationship of mutual constraint between negative and positive correlations, and considering the installation space of the pressure chamber of a conventional oil and gas drilling drill collar 201, the ratio of the thickness of the first receiving magnetic core to the diameter of the drill collar 201 can be set within a preset range, such as [5 / 24, 7 / 24]. For a drill collar 201 with a diameter of 120mm, the thickness of the first receiving magnetic core is between 25mm and 35mm, such as 30mm. If the thickness is too large, the magnetic reluctance of the magnetic core will increase significantly, the magnetic field focusing ability will decrease drastically, resulting in a decrease in the overall sensitivity of the system, and it may also exceed the limited installation space inside the pressure chamber of the drill collar 201; if the thickness is too small, the effective cross-sectional area will be insufficient, and it will be unable to gather enough magnetic flux to achieve the magnetic field enhancement effect. The specific material, axial length, and cross-sectional shape of the first receiving magnetic core can be flexibly adjusted according to the drill collar specifications, downhole operating conditions, and detection distance requirements, and this disclosure does not impose a unique limitation on them.

[0036] The azimuth reference unit 302 is used to acquire real-time attitude angle data of the drilling tool 20 during its rotation. The real-time attitude angle data represents the geometric angle set of the instantaneous attitude and rotation state of the drilling tool 20 in the three-dimensional underground space, including at least one of the following: tool face angle, well inclination angle, and azimuth angle.

[0037] The tool face angle represents the real-time rotation angle of the sensor 301 within the cross-section of the drill collar 201 (the orientation of the major axis of the first receiving magnetic core) relative to a preset reference orientation, ranging from 0° to 360°, and changing periodically and continuously with the rotation of the drill collar 201. The well inclination angle represents the angle between the central axis of the drill collar 201 (wellbore axis) and the Earth's plumb line, ranging from 0° to 90°, where 0° represents a vertical well and 90° represents a horizontal well, used to describe the inclination of the wellbore. The azimuth angle represents the projection of the tangent of the central axis of the drill collar 201 onto a horizontal plane, a clockwise angle relative to geographic true north, ranging from 0° to 360°, used to describe the overall orientation of the wellbore underground. Real-time attitude angle data can be measured by high-frequency sampling of the microelectromechanical system (MEMS) gyroscope in the azimuth reference unit 302, with drift correction performed in conjunction with a triaxial accelerometer. The measurement accuracy is not less than 0.1°, and the sampling rate is synchronized with the sensor 301 (not less than 10kHz). For example, at a certain sampling moment, the well inclination angle of the drilling tool 20 is 85 degrees, the azimuth angle is 45 degrees, and the tool face angle is 120 degrees.

[0038] The processing unit 303 is configured to synchronously acquire induced magnetic signals and real-time attitude angle data; perform statistical processing on multiple induced magnetic signals belonging to the same azimuth interval to obtain the comprehensive signal intensity corresponding to each azimuth interval; and determine the azimuth and distance information of the target well relative to the drilling tool based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals.

[0039] When the drilling tool 20 is rotating and drilling at the rated speed, the processing unit 303 acquires the first induced magnetic signal and the real-time attitude angle data output by the orientation reference unit 302 at the same timestamp at a preset sampling rate (e.g., 1000Hz). This is the tool face angle, and a set of correspondences between the first induced magnetic signal and the real-time attitude angle is obtained.

[0040] The rotation space of the drilling tool 20 is divided into multiple azimuth intervals. An azimuth interval refers to a discrete angular sector obtained by evenly dividing the 360-degree azimuth space around the drilling tool 20's own axis. Each azimuth interval corresponds to a fixed range of tool face angle values. For example, if the 360-degree space is divided into 32 azimuth intervals, the first azimuth interval covers 0 to 11.25 degrees, the second azimuth interval covers 11.25 to 22.5 degrees, and so on. The 32 azimuth intervals completely cover the full azimuth space of the drilling tool 20's rotation.

[0041] The processing unit 303 analyzes the synchronously acquired real-time attitude angle data in real time, determines the azimuth interval to which the measurement direction of the drilling tool 20 belongs at the current moment, and then stores the first induced magnetic signal corresponding to the same timestamp into the buffer corresponding to the azimuth interval. After the drilling tool 20 completes at least one full rotation cycle and achieves a complete 360° full-circle azimuth space scan, the processing unit 303 performs mathematical statistical operations on the first induced magnetic signal accumulated in the buffer corresponding to each azimuth interval. The operation methods include, but are not limited to, arithmetic mean, moving weighted average, time-domain integration, peak filtering and mean statistics, etc., and finally outputs the comprehensive signal strength corresponding to each azimuth interval.

[0042] The comprehensive signal strength refers to the numerical value obtained through mathematical statistical calculations within a certain azimuth interval, which can quantitatively characterize the average energy and amplitude characteristics of the magnetic field of the target well 10 within that azimuth interval. The distribution characteristics refer to the overall variation and extreme value distribution law of the comprehensive signal strength corresponding to all azimuth intervals in a 360° polar coordinate system. The phase of this distribution characteristic (the position where the peak occurs) characterizes the spatial orientation of the target well 10 relative to the drilling tool 20; the amplitude of the distribution characteristic (the magnitude of the peak) reflects the intensity attenuation law of the magnetic field source of the target well 10. By analyzing this distribution characteristic, the azimuth and distance information of the target well can be calculated simultaneously.

[0043] Specifically, for determining the orientation, the processing unit 303 constructs the distribution characteristic curve of the comprehensive signal intensity of all orientation intervals within at least one rotation cycle in the 360° full-circle space, and then calls the peak finding algorithm (including but not limited to threshold method, first derivative peak finding method, Gaussian fitting peak finding algorithm, etc.) to complete the peak identification.

[0044] Since the first receiving magnetic core and the first induction coil are arranged along the axial direction of the drilling tool 20 in this embodiment, during the synchronous rotation of the drilling tool 20 and the sensor 301, the magnetic field formed by the target well 10 in the wellbore space will be periodically modulated by the axially arranged sensor 301, which rotates continuously with the drilling tool 20: when the first receiving magnetic core is facing the target well 10 and is closest to the target well 10, the magnetic flux passing through the first induction coil reaches its peak value; when the first receiving magnetic core is facing the target well 10 and is farthest from the target well 10, the magnetic flux passing through the first induction coil drops to its trough value.

[0045] Thus, the originally static magnetic field of the target well 10 is converted into an alternating signal that is completely synchronized with the rotation cycle of the drilling tool 20, and whose amplitude changes periodically with the real-time tool face angle. Therefore, the processing unit 303 can determine the azimuth of the target well 10 relative to the drilling tool 20 by the center angle of the target azimuth interval where the peak point of the comprehensive signal intensity is located; or it can determine the azimuth of the target well 10 by curve fitting the comprehensive signal intensity of the entire 360° azimuth interval and determining the peak phase of the fitted curve.

[0046] For example, such as Figure 5 As shown, one rotation cycle is divided into 16 azimuth intervals, S0 to S15, as illustrated in the figure. The location of target well 10 is indicated by an asterisk. Azimuth intervals S2 and S10 are directly opposite target well 10. In a polar coordinate system where the horizontal axis represents the azimuth intervals and the vertical axis represents the overall signal strength, it can be seen that the peak point corresponds to azimuth interval S2, and the valley point corresponds to azimuth interval S10. Therefore, the center angle of azimuth interval S2, which takes positive values, can be determined as the azimuth of target well 10. Furthermore, based on the fitted curve, the angle of the position point corresponding to the peak value can be determined as the azimuth of target well 10.

[0047] Since, under the same sensor sensitivity and rotation speed, the peak amplitude of the combined signal strength satisfies a preset inverse mapping relationship with the distance between the target well 10 and the drilling tool 20, its quantification relationship can be characterized as follows: ,in, This represents the peak amplitude of the overall signal strength across the entire azimuth range. This indicates the distance between drilling tool 20 and target well 10. This is the magnetic field attenuation coefficient (typically 3, conforming to the cubic attenuation law of the magnetic dipole in the magnetization magnetic field of ferromagnetic casing). The processing unit 303 can determine the distance information between the drilling tool 20 and the target well 10 by calling a pre-stored distance inversion formula or calibration curve. The distance inversion formula and calibration curve are pre-established databases that map the peak amplitude of the comprehensive signal intensity to the distance to the target well 10 under different well spacing, well inclination angle, formation permeability, and downhole temperature conditions.

[0048] Furthermore, the redundancy of the sensors 301 is designed to improve the completeness and accuracy of the acquired induced magnetic signals. The central axes of the multiple sensors 301 are collinear and parallel, and the projection points of the center points of the sensors 301 onto the central axis of the drill collar 201 are at different positions. The axial spacing between adjacent sensors 301 relative to the drill collar 201 can be adjusted according to the space of the pressure chamber. The structural parameters of each sensor 301 remain completely identical. Multiple sensors 301 can synchronously acquire the induced magnetic signals of the casing 101's magnetic field at different axial positions in the same orientation. The induced magnetic signal corresponding to each real-time attitude angle data is updated to the sum or average of multiple induced magnetic signals, thereby reducing missed detections and increasing the likelihood of picking up weak magnetic fields.

[0049] In this embodiment, the sensor 301 adopts a combination structure of a first receiving magnetic core and a first induction coil arranged along the axial direction of the drilling tool 20. This design maximizes the magnetic flux convergence capability of the radiated magnetic field of the target well 10, and realizes high sensitivity in picking up the weak magnetic field of the target well 10. At the same time, the processing unit 303 transforms the continuous rotational motion of the drilling tool 20 into a discrete scan of the 360° space around the well by discretizing the azimuth interval and statistically processing the induced magnetic signal in the same azimuth interval. This effectively extracts the periodic comprehensive signal intensity that is strongly correlated with the azimuth. The random electromagnetic interference downhole and the vibration interference of the drilling tool 20 are both random noises without fixed azimuth rules and do not repeat with the rotation period of the drilling tool 20. In the statistical processing of multiple sampling points in the same azimuth interval, such random interferences may cancel each other out and have their amplitude attenuated. The comprehensive signal intensity that is strongly correlated with the azimuth will be continuously accumulated in the same azimuth interval, and the signal-to-noise ratio will be significantly improved, thereby realizing the positioning of the target well 10.

[0050] In deep well and long horizontal section oil and gas drilling operations, the total length of the drilling tool 20 can reach several kilometers. The drill pipe 203 and drill collar 201 in the long horizontal section have a large contact area with the well wall and extremely high frictional torque, which can easily cause stick-slip vibration in the torsional direction of the drilling tool 20. This manifests as follows: when the static friction between the drill bit 202 and the formation, and between the drill pipe 203 and the drill collar 201 and the well wall causes the drill bit 202 to stick and stop rotating, the surface drilling rig continues to drive the upper drill pipe 203 to rotate, so that the entire section of the drilling tool 20 continues to store elastic torsional potential energy. When the accumulated torque of the drilling tool 20 exceeds the static friction limit, the drill bit 202 slips instantly, and the elastic potential energy stored in the drilling tool 20 is released in a concentrated manner, causing the instantaneous rotational speed of the drill bit to soar to several times the rated speed. During the stick-slip vibration viscous stop phase, the instantaneous angular velocity of drill collar 201 approaches 0. Even if sensor 301 is facing the target well 10, the rate of change of magnetic flux is almost 0, and the amplitude of the induced magnetic signal drops sharply, failing to reflect the true spatial magnetic field strength. During the slip phase, the instantaneous rotational speed of drill collar 201 spikes by orders of magnitude. Even if the magnetic field strength of the target well 10 does not change, a transient voltage spike with a large amplitude, independent of the magnetic field, will be generated in the first induction coil.

[0051] Based on this, the processing unit 303 in this embodiment is configured to: determine the instantaneous angular velocity based on real-time attitude angle data; determine the corresponding weighting factor for the induced magnetic signal based on the instantaneous angular velocity; and determine the weighted cumulative value of the induced magnetic signals in the same azimuth interval as the comprehensive signal strength based on the weighting factor.

[0052] Instantaneous angular velocity refers to the rate of change of the angle of rotation of the drilling tool 20 about its central axis. Ideally, the angular velocity of the drilling tool 20 should be equal to the rated rotational speed of the drilling rig on the ground.

[0053] It is understandable that the processing unit 303 records the real-time attitude angle data of the orientation reference unit 302 in two consecutive intervals using its internal high-speed clock (e.g., a 100MHz crystal oscillator). time interval Then the instantaneous angular velocity .

[0054] The weighting factor refers to the numerical multiplier assigned to the induced magnetic signal at a specific sampling point during statistical processing, used to adjust the contribution ratio of that sampling point to the final comprehensive signal strength. It can be understood that a smooth mapping relationship is established between instantaneous angular velocity and the weighting factor; the larger the instantaneous angular velocity, the larger the corresponding weighting factor, and vice versa. When the instantaneous angular velocity equals the rated speed of the drilling rig, the weighting factor is 1.

[0055] Alternatively, the state of the drilling tool 20 can be determined based on the instantaneous angular velocity, and different weighting factors can be assigned to different states. Specifically, when the instantaneous angular velocity is less than or equal to the viscosity threshold, the corresponding weighting factor is determined as the first weighting factor; when the instantaneous angular velocity is greater than or equal to the slip threshold, the corresponding weighting factor is determined as the second weighting factor; when the instantaneous angular velocity is greater than the viscosity threshold but less than the slip threshold, the corresponding weighting factor is determined as the third weighting factor; wherein, the first weighting factor is less than the third weighting factor, and the third weighting factor is less than the second weighting factor.

[0056] When the instantaneous angular velocity is less than or equal to the viscosity threshold (e.g., below 2.1 rad / s), the drill bit 202 jams or creeps extremely slowly, entering a viscous stop state. In this state, the rate at which the first induction coil cuts the magnetic field approaches zero, and the induced electromotive force becomes extremely small, being overwhelmed by the thermal noise of the instruments inside the drilling tool 20, low-frequency geomagnetic drift noise, and electronic background noise. The signal acquired at this time has a low signal-to-noise ratio. If these noise signals are added to the overall signal strength, the true characteristics of this azimuth range will be reduced. Therefore, the processing unit 303 assigns a first weighting factor, such as 0.1 or even 0, to penalize and suppress the noise in the viscous stop state.

[0057] When the instantaneous angular velocity is greater than the viscosity threshold and less than the slip threshold, the drilling tool 20 is in a relatively stable normal rotational state. In this state, the induced electromotive force picked up by the first induction coil exhibits a linear proportional relationship with the magnetic field strength, resulting in a high signal-to-noise ratio. Therefore, the processing unit 303 assigns a third weighting factor, for example, 1.0.

[0058] When the instantaneous angular velocity is greater than or equal to the slip threshold (e.g., higher than 23 rad / s), the drilling tool 20 is in a slip state. In this state, when the drilling tool passes through a certain azimuth interval with an extremely high instantaneous angular velocity, the dwell time is very short, and at a fixed sampling rate, the number of sampling points captured in this azimuth interval is very small. However, this embodiment uses a weighted cumulative value, and the reduction in the number of sampling points will lead to a significant decrease in the overall signal strength of this azimuth interval. In addition, although the instantaneous angular velocity is increased by N times, the first induction coil and the first receiving magnetic core have inherent parasitic inductance and eddy current losses, which cause them to form a physical low-pass filter. Therefore, the voltage peak generated at the moment of slip cannot be amplified linearly by N times, but is severely suppressed by frequency response (i.e., the actual voltage increase is much smaller than the speed increase). In summary, in the slip state, the processing unit 303 assigns a large second weighting factor, such as 1.8, to increase its overall signal strength, so that it can realistically and equivalently restore the physical distribution of the spatial magnetic field in this azimuth interval.

[0059] Due to the complex environment of deep well operations, stick-slip vibration is very likely to occur. This embodiment of the present disclosure introduces instantaneous angular velocity to avoid the problem of a sudden increase or decrease in the number of sampling points in a certain azimuth interval caused by stick-slip vibration, which leads to the distortion of the corresponding comprehensive signal strength. Through weighting factors, it is ensured that the target well 10 can be accurately located even under the extreme working conditions of stick-slip vibration.

[0060] Furthermore, in extreme cases, the instantaneous release of torque can cause the drilling tool 20 to sweep across certain azimuth zones at extremely high instantaneous angular velocities. This rapid sweeping may result in very few sampling points within these azimuth zones, thereby compromising the integrity of the spatial scan.

[0061] In this embodiment of the present disclosure, before determining the comprehensive signal strength, the processing unit 303 extracts the historical comprehensive signal strength corresponding to the target azimuth interval within the historical rotation cycle for target azimuth intervals where the total number of induced magnetic signals is lower than the determination threshold; performs interpolation compensation based on the historical comprehensive signal strength to generate the reconstructed signal strength of the target azimuth interval in the current rotation cycle, and determines the reconstructed signal strength as the comprehensive signal strength corresponding to the target azimuth interval.

[0062] The judgment threshold is a pre-set minimum number of effective induced magnetic signal sampling points that must be satisfied within a certain azimuth interval; for example, the judgment threshold is set to 3. The historical rotation cycle refers to the 360° rotation cycle that the drilling tool 20 has completely traversed before the current time point. Because the geological environment and the relative position of the drilling tool 20 and the target well 10 change extremely slowly in a very short time (e.g., a few seconds), the data collected in the first few rotations at the same spatial angle have extremely strong temporal continuity and spatial correlation. If the data from the nth rotation is currently being processed, then the (n-1)th rotation, the (n-2)th rotation, etc., are the historical rotation cycles.

[0063] The specific implementation process is as follows: When the number of induced magnetic signals in the target azimuth interval (e.g., the 8th azimuth interval) is lower than the judgment threshold, the processing unit 303 traces back and extracts the historical comprehensive signal intensity of the target azimuth interval over the past m (m is greater than 0, e.g., m=5) complete rotation cycles. The processing unit 303 calls the internal hardware multiplier-accumulator, uses the time or period sequence as the independent variable and the historical comprehensive signal intensity as the dependent variable, and performs moving weighted average or higher-order spline interpolation, linear interpolation, etc., to obtain the reconstructed signal intensity. This reconstructed signal intensity is determined as the comprehensive signal intensity of the target azimuth interval in the current cycle.

[0064] In this embodiment of the disclosure, when encountering extreme slip vibration, the number of induced magnetic signals in the target orientation interval is extremely small. If noise is present, the statistical processing at this time will result in the comprehensive signal intensity being dominated by noise, which cannot truly reflect the magnetic field of the target well 10. However, the drilling tool 20 usually advances at a speed of only a few meters to a dozen meters per hour in the formation. Therefore, within several consecutive rotation cycles (a few seconds), the relative position of the drilling tool 20 and the target well 10 remains almost unchanged. Therefore, interpolation compensation using historical comprehensive signal intensity can make up for the incompleteness of data within one rotation cycle under extreme slip conditions.

[0065] In actual drilling collision avoidance or connection operations, the relative distance between the drilling tool 20 and the target well 10 is dynamically changing (gradually approaching from tens of meters to a few meters or even intersecting). Since the passive magnetic field strength of the target well 10 decreases nonlinearly with distance, a fixed azimuth interval division method cannot simultaneously achieve high sensitivity at long distances and high resolution at close distances.

[0066] Therefore, by introducing a dynamic adjustment mechanism, the processing unit 303 is configured to: acquire the signal-to-noise ratio characteristics of the induced magnetic signal; and adjust the number of azimuth intervals based on the signal-to-noise ratio characteristics.

[0067] The signal-to-noise ratio (SNR) characteristic represents the ratio of the effective induced magnetic signal generated by the target well 10 to the background noise intensity in the well within a specific time window or spatial period. For example, when the drilling tool 20 is far from the target well 10 (e.g., 30 meters), the calculated SNR characteristic is less than 3 dB, and the induced magnetic signal is almost completely submerged by noise; when it approaches the target well (e.g., 5 meters), the SNR characteristic is greater than 20 dB, and the peak value is clear and significant.

[0068] Understandably, the specific process for determining the signal-to-noise ratio (SNR) characteristics is as follows: During drilling, the processing unit 303 caches the combined signal intensity of all azimuth intervals within the past K rotation cycles (K > 0, e.g., K = 5) in memory. The processing unit 303 obtains the SNR characteristics by calculating the peak significance of this data set across a 360-degree distribution. Specifically, the calculation method involves extracting the absolute maximum value from the distribution characteristics and calculating the average of the combined signal intensity of all other non-adjacent azimuth intervals. The ratio or logarithmic difference between the two is then determined as the SNR characteristics under the current operating conditions.

[0069] After determining the signal-to-noise ratio (SNR) characteristics, the processing unit 303 internally presets a first threshold (e.g., 5 dB) and a second threshold (e.g., 15 dB). For low SNR conditions (merged intervals): when the calculated SNR characteristics are less than the first threshold, it indicates that the target well 10 is far away, the induced magnetic signal is extremely weak, and the spatial gradient is gentle. The processing unit 303 reduces the number of azimuth interval divisions M, for example, from the default 32 to 16. For high SNR conditions (subdivided intervals): when the SNR characteristics are greater than the second threshold, it indicates that the drill bit 202 has approached the target well 10, the induced magnetic signal is extremely strong, and the azimuth characteristics are extremely clear. The processing unit 303 increases the number of azimuth interval divisions M, for example, from the default 32 to 64.

[0070] Under this dynamic adjustment mechanism, at long distances, the induced magnetic signal is extremely weak and contaminated by broadband mechanical noise. In this case, azimuth resolution is secondary; the primary task is to locate the target well 10. By reducing the number of divisions, the azimuth angle of a single azimuth interval is multiplied, increasing the number of signal sampling points falling into a single interval at the same rotational speed. This improves the integrated energy and statistical confidence of the weak induced magnetic signal, effectively extending the maximum detection range of the target well 10. At close range, the induced magnetic signal strength is sufficiently high, and noise can be suppressed without accumulating too many sampling points. At this point, the drilling tool 20 faces a very high risk of collision, and collision avoidance requires extremely high directional accuracy. Therefore, by increasing the number of divisions, the azimuth pointing accuracy is improved.

[0071] During deep well drilling, the bottom-hole static temperature increases with depth, reaching over 175°C. Extreme downhole temperatures directly alter the physical characteristics of the first induction coil in sensor 301, causing nonlinear drift in the coil's parasitic inductance, capacitance, DC resistance, and insulation impedance. This leads to distortions in the coil's amplitude and phase frequency responses, ultimately resulting in abnormal amplitude attenuation and phase shift in the acquired induced magnetic signal. Consequently, the acquired signal fails to accurately reflect the magnetic field characteristics of the target well 10, causing deviations in subsequent azimuth and distance calculations.

[0072] In this embodiment, the processing unit 303 is configured to acquire the current temperature data of the downhole environment where the sensor 301 is located; based on the current temperature data, call a pre-established compensation calibration table to determine a dynamic compensation coefficient that matches the current temperature data, and use the dynamic compensation coefficient to compensate the induced magnetic signal.

[0073] The compensation calibration table includes the amplitude attenuation rate and phase shift angle of sensor 301 under different temperature conditions, used to quantify the degree of signal distortion caused by high temperature. This compensation calibration table is pre-built, and the construction process is as follows: The sensor 301 to be calibrated is placed in a programmable high-temperature constant-temperature chamber. Step-by-step temperature increase nodes are set within the entire temperature range of downhole operations, for example, increasing the temperature step-by-step from 20℃ to 175℃. After the temperature stabilizes at each fixed temperature node (20℃, 50℃, 75℃, 100℃, 125℃, 150℃, 175℃), a pre-defined bandwidth sweep frequency excitation signal is injected into the first induction coil. The actual amplitude-frequency response and phase-frequency response of the coil at that temperature are collected and recorded. Using the response at room temperature of 20℃ as a benchmark, the amplitude attenuation rate and phase shift angle at each temperature relative to the benchmark are calculated. The correspondence between temperature, amplitude attenuation rate, and phase shift angle is stored in the compensation calibration table.

[0074] The dynamic compensation coefficient is a coefficient extracted or interpolated from the compensation calibration table and can be directly used to correct the induced magnetic signal. If the high temperature reduces the output amplitude of the coil, the dynamic compensation coefficient is an amplitude amplification factor greater than 1; if the high temperature causes the signal phase to lag, the coefficient includes a leading phase angle to compensate for the lag. For example, if the calibration table shows that the phase shift angle at 142℃ is 3° phase lag, then the dynamic compensation coefficient is 3° advance, and the processing unit 303 advances the induced magnetic signal by 3° on the time axis through a phase correction algorithm; if the amplitude decreases by 10%, then the dynamic compensation coefficient is an amplitude increase of 1.11, multiplying the amplitude of the induced magnetic signal by 1.11.

[0075] For example, during downhole operations, if the real-time temperature data is 142℃, the processing unit 303 will find the amplitude attenuation rate and phase shift angle corresponding to adjacent 100℃ and 150℃ in the compensation calibration table. Through bilinear interpolation or polynomial fitting algorithm, it will calculate the amplitude attenuation rate and phase shift angle at 142℃, and then generate the corresponding dynamic compensation coefficient to amplify the amplitude and correct the phase of the original induced magnetic signal, restoring it to a distortion-free real signal.

[0076] It should be noted that the compensation is completed after the acquisition of the induced magnetic signal and before the statistical processing of the azimuth interval; the comprehensive signal intensity of each subsequent azimuth interval is statistically processed based on the compensated induced magnetic signal to ensure that the azimuth calculation is not affected by high temperature distortion.

[0077] In this embodiment of the disclosure, the dynamic compensation coefficient under the current temperature data is determined by a pre-stored compensation calibration table, which avoids the frequency response change caused by the parasitic capacitance and resistance drift of the coil of sensor 301 due to high downhole temperature. This ensures that the compensated induced magnetic signal can truly and accurately reflect the amplitude and phase characteristics of the magnetic field generated by the target well 10, thereby ensuring the reliability and accuracy of azimuth detection in high-temperature downhole conditions.

[0078] In actual drilling operations, in addition to conventional vertical wells, there may also be wellbores with complex three-dimensional trajectories, such as horizontal wells with large displacement, deviated wells with large angles, three-dimensional obstacle avoidance wells, and cross-rescue wells. Under these conditions, the relative spatial attitude between the drilling tool 20 and the target well 10 changes continuously in real time. For this type of condition, such as... Figure 6 As shown, the sensor 301 in this embodiment further includes: a second receiving magnetic core 3013 and a second induction coil 3014 arranged radially along the drilling tool 20, and a third receiving magnetic core 3015 and a third induction coil 3016 arranged tangentially along the drilling tool 20. The induced magnetic signal includes a second induced magnetic signal in the axial direction and a third induced magnetic signal in the tangential direction generated by the magnetic field generated by the target well 10.

[0079] The first receiving magnetic core 3011, the second receiving magnetic core 3013, and the third receiving magnetic core 3015 form a three-dimensional orthogonal measurement node. The dashed line represents the central axis, and the central axis of the third receiving magnetic core 3015 is represented by a dot.

[0080] The processing unit 303 uses a three-channel synchronous high-precision analog-to-digital converter to simultaneously acquire the AC voltage signals at both ends of the first, second, and third induction coils based on the same clock reference during the continuous rotation of the drilling tool 20. The resulting first, second, and third induction magnetic signals are then processed.

[0081] Subsequently, multiple sampling points of the first, second, and third induced magnetic signals falling within the same azimuth interval are subjected to independent arithmetic averaging or integral accumulation processing to obtain the initial composite signal intensity in the three directions for each azimuth interval. The processing unit 303 then performs spatial vector synthesis on the initial composite signal intensity in the three directions. This can be achieved by calculating the magnitude of the initial composite signal intensity in the three directions to obtain the composite signal intensity in scalar form; alternatively, a 3×3 magnetic gradient tensor matrix can be constructed using the initial composite signal intensity in the three directions and their spatial derivatives, and the eigenvalues ​​or normalized source intensities of this magnetic gradient tensor matrix can be used as the composite signal intensity corresponding to that azimuth interval.

[0082] A magnetic field is a directional three-dimensional vector. When the drilling tool 20 approaches the target well 10 at a large angle or even a vertical angle, the magnetic field lines radiated from the target well 10 may be exactly perpendicular to the central axis of the first receiving magnetic core. At this time, the effective magnetic flux passing through the first receiving magnetic core is zero. By adding radial and tangential receiving channels, regardless of the spatial angle at which the magnetic field lines are incident, at least one non-zero magnetic flux component will be generated on the three orthogonal projection planes of radial, axial, and tangential directions, thereby improving the ability to capture the weak magnetic field generated by the target well 10.

[0083] In actual operation of passive ranging, the magnetic field generated by the casing 101 is extremely weak, typically ranging from a few nT to tens of nT. However, the Earth itself has a geomagnetic background field with an intensity of 40,000 to 60,000 nT. When the drilling tool 20 rotates continuously downhole, the axially or orthogonally arranged sensors 301 cut the Earth's magnetic field lines, thereby generating a sinusoidal interference with a very large amplitude in the induction coil. In this embodiment, the processing unit 303 is equipped with a geomagnetic field reference model and is configured to, before performing statistical processing, combine real-time attitude angle data with the geomagnetic field reference model to determine the theoretical projection components of the geomagnetic background field in each measurement direction of the sensor 301; and determine the difference between the induced magnetic signal and the projection component as the updated induced magnetic signal.

[0084] A geomagnetic field reference model is a set of mathematical models based on geophysics that can calculate the theoretical strength and direction (magnetic declination and magnetic dip) of the Earth's static magnetic field at a given geographical location, latitude, depth, and time. Commonly used international standard geomagnetic field reference models include the International Geomagnetic Reference Field or the World Geomagnetic Model. For example, if the coordinates of new wellbore 11 are 30°N, 105°E, and the date is 2026, the geomagnetic field reference model will output that the total geomagnetic field strength of new wellbore 11 is 49,500 nT, the magnetic dip is 45°, and the magnetic declination is -3°.

[0085] The processing unit 303 loads the geomagnetic field reference model and calculates the absolute component vector of the geomagnetic background field at the current depth in the global geographic coordinate system. In the global geographic coordinate system, the north axis points to geographic north, the east axis points to geographic east, and the ground axis points vertically downward (in line with the direction of gravity).

[0086] During drilling, the drilling tool 20 rotates at high speed. The processing unit 303 receives the well inclination angle, azimuth angle, and tool face angle monitored by the azimuth reference unit 302 in real time. Using the well inclination angle, azimuth angle, and tool face angle, a 3×3 direction cosine rotation matrix is ​​constructed in real time. By multiplying the absolute component vector in the global geographic coordinate system with the direction cosine rotation matrix through matrix multiplication, the theoretical projection components of the geomagnetic background field in each measurement direction of the sensor 301 are obtained.

[0087] The processing unit 303 subtracts the theoretical projection component of the corresponding direction from the induced magnetic signal in each direction obtained from the sensor 301 to obtain the updated induced magnetic signal in each direction, and then performs subsequent statistical processing based on the updated induced magnetic signal.

[0088] In this embodiment of the present disclosure, before entering the statistical processing, the theoretical projection component of the geomagnetic background field is subtracted from the induced magnetic signal. Because the geomagnetic background field has been removed from the updated induced magnetic signal, the subsequent azimuth interval statistical processing can amplify and find the peak of the magnetic field of the target well 10, thereby realizing the long-distance positioning of the target well 10 in a complex geomagnetic environment.

[0089] like Figure 7 As shown, this disclosure provides a passive, passive drilling wellbore detection method. Taking the processing unit 303 as the execution subject as an example, the method may include the following steps S701 to S703.

[0090] In step S701, the induced magnetic signal corresponding to the magnetic field generated by the target well and the real-time attitude angle data of the drilling tool are acquired simultaneously. The induced magnetic signal includes a first induced magnetic signal of the magnetic field in the axial direction.

[0091] In step S702, based on real-time attitude angle data, multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to generate a comprehensive signal intensity corresponding to each azimuth interval. The rotation space of the drilling tool is divided into multiple azimuth intervals.

[0092] In step S703, the azimuth and distance information of the target well relative to the drilling tool are determined based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals.

[0093] This disclosure also provides a computer-readable storage medium storing at least one instruction that is executed by a processor to implement the passive, passive borehole detection method as described in the above embodiments.

[0094] This disclosure also provides a computer program product including computer instructions stored in a computer-readable storage medium; a processor of an electronic device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the electronic device to perform the passive passive drilling detection method described in the above embodiments.

[0095] This disclosure also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described passive drilling well detection method embodiments and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0096] It should be understood that the chip mentioned in the embodiments of this disclosure may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0097] In the several embodiments provided in this disclosure, it should be understood that the disclosed systems, apparatuses, servers, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0098] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0099] Furthermore, the functional units in the various embodiments of this disclosure can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0100] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory, random access memory, magnetic disks, or optical disks.

[0101] Those skilled in the art will recognize that the functions described in this disclosure in one or more of the examples above can be implemented using hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0102] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0103] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A passive, passive drilling detection device, applied to drilling tools, characterized in that, The device is disposed within the pressure chamber of the drilling tool, and the device includes: At least one sensor is used to acquire an induced magnetic signal corresponding to the magnetic field generated by the target well. The sensor includes a first receiving magnetic core and a first induction coil arranged along the axial direction of the drilling tool. The induced magnetic signal includes a first induced magnetic signal corresponding to the magnetic field in the axial direction. An orientation reference unit is used to acquire real-time attitude angle data of the drilling tool during rotation. The processing unit, communicatively connected to both the sensor and the orientation reference unit, is configured to: synchronously acquire the induced magnetic signal and the real-time attitude angle data; and, Based on the real-time attitude angle data, multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to obtain the comprehensive signal intensity corresponding to each azimuth interval. The rotation space of the drilling tool is divided into multiple azimuth intervals; and... Based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals, the azimuth and distance information of the target well relative to the drilling tool are determined.

2. The apparatus according to claim 1, characterized in that, The thickness of the first receiving magnetic core is determined based on a preset magnetic field enhancement model. The magnetic field enhancement model characterizes the detection sensitivity as being positively correlated with the relative permeability and effective cross-sectional area of ​​the first receiving magnetic core, and negatively correlated with the thickness.

3. The apparatus according to claim 1 or 2, characterized in that, The processing unit is configured as follows: Based on the real-time attitude angle data, the instantaneous angular velocity is determined; Based on the instantaneous angular velocity, determine the corresponding weighting factor for the induced magnetic signal; Based on the weighting factor, the weighted cumulative value of the induced magnetic signals within the same azimuth interval is determined as the comprehensive signal strength.

4. The apparatus according to claim 3, characterized in that, The processing unit is configured as follows: When the instantaneous angular velocity is less than or equal to the viscosity threshold, the corresponding weighting factor is determined as the first weighting factor; When the instantaneous angular velocity is greater than or equal to the slip threshold, the corresponding weighting factor is determined as the second weighting factor based on the instantaneous angular velocity; When the instantaneous angular velocity is greater than the viscosity threshold and less than the slip threshold, the corresponding weighting factor is determined to be the third weighting factor; Wherein, the first weighting factor is less than the third weighting factor, and the third weighting factor is less than the second weighting factor.

5. The apparatus according to claim 1, characterized in that, The processing unit is configured as follows: When the number of induced magnetic signals in the target orientation interval is lower than the judgment threshold, the historical comprehensive signal intensity corresponding to the target orientation interval within the historical rotation cycle is extracted. Interpolation compensation is performed based on the historical comprehensive signal strength to generate the reconstructed signal strength of the target azimuth interval in the current rotation cycle, and the reconstructed signal strength is determined as the comprehensive signal strength corresponding to the target azimuth interval.

6. The apparatus according to claim 1, characterized in that, The processing unit is configured as follows: Obtain the signal-to-noise ratio characteristics of the induced magnetic signal; Based on the signal-to-noise ratio characteristics, the number of divisions of the azimuth interval is adjusted.

7. The apparatus according to claim 1, characterized in that, The processing unit is configured to acquire the current temperature data of the downhole environment where the sensor is located; Based on the current temperature data, a pre-established compensation calibration table is called to determine a dynamic compensation coefficient that matches the current temperature data. The compensation calibration table includes the amplitude attenuation rate and phase offset angle of the sensor under different temperature conditions. The induced magnetic signal is compensated using the dynamic compensation coefficient.

8. The apparatus according to claim 1, characterized in that, The sensor further includes a second receiving magnetic core and a second induction coil arranged radially along the drilling tool, and a third receiving magnetic core and a third induction coil arranged tangentially along the drilling tool. The induced magnetic signal includes a second induced magnetic signal of the magnetic field in the axial direction and a third induced magnetic signal in the tangential direction.

9. The apparatus according to claim 1, characterized in that, The processing unit is equipped with a geomagnetic field reference model; The processing unit is configured to, before performing the statistical processing, combine the real-time attitude angle data with the geomagnetic field reference model to determine the theoretical projection components of the geomagnetic background field in each measurement direction of the sensor. The difference between the induced magnetic signal and the projected component is used to determine the updated induced magnetic signal.

10. A passive, passive drilling-while-drilling wellbore detection method, characterized in that, The method includes: The induced magnetic signal corresponding to the magnetic field generated by the target well and the real-time attitude angle data of the drilling tool are acquired simultaneously. The induced magnetic signal includes the first induced magnetic signal of the magnetic field in the axial direction. Based on the real-time attitude angle data, multiple induced magnetic signals belonging to the same azimuth interval are statistically processed to generate a comprehensive signal intensity corresponding to each azimuth interval, and the rotation space of the drilling tool is divided into multiple azimuth intervals. Based on the distribution characteristics of the comprehensive signal intensity corresponding to multiple azimuth intervals, the azimuth and distance information of the target well relative to the drilling tool are determined.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the passive, passive drilling detection method as described in claim 10.

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