Gamma sector distinguishing method for near-bit

Abstract

The invention relates to a gamma sector distinguishing method for a near-bit, and relates to the technical field of oil-gas exploration and development. According to the method provided by the embodiment of the invention, the angular difference problem of the near-bit instrument is automatically processed through the processing of the initial angular difference, the free configuration of the angular difference is realized, and if the mounting position is changed, the trouble in the dismounting process can be reduced. And the difference value between the gravity tool face and the magnetic tool face is collected through an external pump stopping signal to serve as the calibration offset. Meanwhile, the theory that the components of the magnetoresistive sensor in the positive and negative directions of the standard magnetic field are opposite numbers is used, and a certain magnetoresistive component is linear accumulation of all axial components in the standard magnetic field. And respectively corresponding component coefficients can be calculated through composite operation between standard positions. The calibration precision is improved, errors caused by component differences or component installation errors in the installation and debugging process are reduced, the influence on the magnetic tool face is reduced, and the linearity and precision of the tool face are improved.

Description

Technical Field

[0001] This application relates to the technical field of oil and gas exploration and development, and particularly to a gamma sector resolution method for near-bit. Background Art

[0002] During the measurement-while-drilling process of oil and gas exploration, the closer the measurement point is to the drill bit, the more accurate the measured data is, and the smaller the data lag is. With the development of complex reservoirs, such as the development of thin oil layers and deep oil layers, the importance of drilling parameters is becoming more and more prominent. In particular, the near-bit azimuth gamma data can accurately reflect the radiation parameters of the formation, which is beneficial to the precise control of the drilling trajectory and the improvement of the drilling encounter rate. However, it is particularly important to eliminate the influence of drill bit vibration on the measurement during the detection process and to dynamically and accurately collect effective formation parameters during the drilling process.

[0003] In the patent document CN104727807A, a method of combining multiple sensors is adopted, such as using three orthogonal acceleration sensors and two axially orthogonal fluxgate sensors. However, in the actual installation process, it is very likely that there will be no strictly orthogonal sensor installation method, so data judgment deviation may occur, resulting in abnormal state judgment.

[0004] In the patent document CN106285632A, the magnitude and direction of the gravitational acceleration and the magnetic induction intensity are used to obtain the tilt angle of the focused gamma sensor, and then this angle is used to determine which coordinate system to use to determine the position of each azimuth. In the patent document CN114563034A, it is also necessary to calculate the gravity tool face of the gravitational acceleration during rotation, and then the difference between the offset between the real-time calculated gravity tool face and the magnetic tool face and the estimated offset is used for phase correction. However, during the actual compound drilling process, the calculation data of the accelerometer will be seriously unbalanced. Even if it can be remedied by an algorithm, it will still lead to inaccurate measurement data accuracy. Therefore, if the coordinate system is selected incorrectly, it will lead to incorrect azimuth judgment, thus affecting the discrimination of the sector. Summary of the Invention

[0005] This application provides a gamma sector resolution method for near-bit to solve the technical problem of how to dynamically and accurately collect effective formation parameters during the drilling process.

[0006] In a first aspect, this application provides a gamma sector resolution method for near-bit, including the following steps: Calculate the weight tool face according to the received gravitational accelerometer components according to a preset rule; According to the magnetic component values of the received magnetoresistive sensor and the component coefficients of the magnetic component values on the orthogonal three axes of the magnetic field, a magnetic tool face is calculated through calibration calculation according to a preset rule. A sector angle difference is calculated based on the difference between the weight tool face and the magnetic tool face. The sector value is calibrated according to the sector angle difference, and the gamma values are stored in different partitions according to the current sector value. The sector duration is counted, and the pulse count is converted into azimuth gamma data according to the set rules.

[0007] Further, before receiving the gravitational accelerometer components, the magnetic component values and the component coefficients of the magnetoresistive sensor, it is necessary to obtain the angle difference each time the device is powered on. The specific steps for obtaining the angle difference include: confirming the initial angle difference according to the position of the corresponding sector in the sector discrimination circuit, and obtaining the latest angular position each time the device is powered on again. Among them, the calculation formula for the angle difference is:

[0008] Where: A is the actual angle difference, i is the count of the sector value during detection, and 0, 1, 2, and 3 respectively represent different regions of the sector.

[0009] Further, the specific state judgment and reception steps for receiving the gravitational accelerometer components, the magnetic component values and the component coefficients of the magnetoresistive sensor include: if the current state is the pump stop state, then receive the components of the weight accelerometer; if it is not in the pump stop state, then receive the three-axis components of the magnetoresistive sensor; obtain the specific sector value through processing based on the three-axis components, and then count the gamma pulses into different sectors.

[0010] Further, the specific steps for obtaining the component coefficients of the magnetic component values on the orthogonal three axes of the magnetic field and the original magnetoresistive component values according to the received magnetic component values of the magnetoresistive sensor include: Calculate the actually collected component values on the three axes :

[0011]

[0012]

[0013] Among them, h x 、h y 、h z are the numerical base offset component values corresponding to the actual component values of each axis, is the component coefficient of the actually collected magnetic component value on the three axes, is the magnetic component value of the actual magnetoresistive sensor on the orthogonal three axes; Let the positive directions of the coordinate axes of the orthogonal magnetic field be X, Y, and Z respectively, and the negative directions be x, y, and z respectively. Then the data measured in the four directions of XYZ, xYz, xyZ, and Xyz are respectively denoted as H1 to H12. The calculated numerical base offset component values corresponding to each axis component are as follows:

[0014] By analogy with formula (5), h can be calculated. y 、h z ; Then, the components in the directions of YxZ, YXz, yXZ, yxz, XzY, xZY, XZy, xyz, etc. at the remaining positions are measured and respectively denoted as H13 to H36. The component coefficients of the actually collected magnetic components on the three axes can be calculated and measured as follows:

[0015] Among them, is the magnetic field component value of the Y-axis of the orthogonal magnetic field; By analogy with formula (6),

[0016] Through formulas (2), (3), and (4), by analogy, the formula is obtained:

[0017] After transformation, it can be obtained:

[0018] Among them, K is the coefficient matrix representation of the magnetoresistance component, is the transformed coefficient matrix, M is the original magnetoresistance component, is the numerical base offset component matrix corresponding to the actual components of each axis, and H is the magnetoresistance component matrix actually collected by the magnetoresistance sensor.

[0019] Furthermore, before calculating the sector angle difference based on the difference between the weight tool face and the magnetic tool face, if the current is in the pump-off state, the component information of the accelerometer and the magnetic component value information of each magnetoresistance sensor are collected, and the weight tool face and the magnetic tool face are calculated, and the difference D is calculated through the weight tool face and the magnetic tool face . The calculation formula is:

[0020] Taking the difference D as the offset of the weight tool face.

[0021] Furthermore, the calculation formula of the weight tool face is:

[0022] where θ is the gravity tool face corresponding angular value, and are the components collected by the gravity accelerometer.

[0023] Further, the calculation formula of the magnetic tool face is:

[0024] where is the angular value corresponding to the magnetic tool face is the magnetic component after Z-axis correction, is the magnetic component after Y-axis correction.

[0025] Further, the specific steps of counting the statistical sector duration and converting the pulse count into azimuth gamma data according to the set rules include: specifying a specific time as a period, within the duration of one period, counting the continuous duration when the gamma count in each sector is not 0. If the gamma count in each sector is not 0, use the continuous duration when the gamma count in each sector is not 0 to calculate the azimuth gamma; if the gamma count in each sector is 0, use the duration of the entire period to calculate the azimuth gamma; convert into pulse count seconds for output according to the cumulative time of the continuous duration when the gamma count in each sector is not 0 and the cumulative value of the azimuth gamma in each sector.

[0026] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the prior art: The method provided by the embodiments of the present application, through the processing of the initial angular difference, automatically processes the angular difference problem of the near-bit instrument itself, realizes the free configuration of the angular difference, and can reduce the trouble in the disassembly and assembly process if the installation position changes. By collecting the difference between the gravity tool face and the magnetic tool face through an external pump stop signal as the calibration offset. At the same time, a magnetoresistive calibration method is provided in the present application. Using the theory that the components of the magnetoresistive sensor in the positive and negative directions of the standard magnetic field are opposite numbers, a certain magnetoresistive component is a linear accumulation of the axis components in the standard magnetic field. Through the composite operation between the standard positions, the corresponding component coefficients can be calculated. It improves the calibration accuracy, reduces the errors caused by component differences or the installation errors of components during installation and debugging, reduces the influence on the magnetic tool face, and improves the linearity and accuracy of the tool face. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application and used together with the specification to explain the principles of the present application. ​

[0028] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] One or more embodiments are exemplarily illustrated by the pictures in the corresponding accompanying drawings. These exemplary illustrations do not limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the drawings in the figures do not constitute a proportional limitation.

[0030] Figure 1 It is a flowchart of a gamma sector discrimination method for near-bit provided in an embodiment of the present application.

[0031] Figure 2 It is a curve graph of magnetic group components before calibration in the calibration method of the calibration frame magnetic group.

[0032] Figure 3 It is a curve graph of magnetic group components after calibration in the calibration method of the calibration frame magnetic group.

[0033] Figure 4 It is a curve graph of the reversed magnetic group components in the calibration method of the calibration frame magnetic group.

[0034] Figure 5 It is a curve graph of magnetic group components with stable rotation in the rotation test experiment.

[0035] Figure 6 It is a curve graph of magnetic group components of the lower sector using a radiation welding rod and the upper sector for comparison in the rotation test experiment. Detailed implementation manners

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0037] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0038] For ease of description, spatially relative relationship terms may be used in the text to describe the relative positional relationship or movement of one element or feature shown in the figure with respect to another element or feature. These relative relationship terms such as "inside", "outside", "inner side", "outer side", "below", "beneath", "above", "over", "front", "rear", etc. This spatially relative relationship term is intended to include different orientations of the device in use or operation other than the orientations depicted in the figure. For example, if the device in the figure undergoes a position flip or attitude change or change in motion state, then these directional indications will change accordingly. For example, an element described as "below other elements or features" or "beneath other elements or features" will subsequently be oriented as "above other elements or features" or "over other elements or features". Therefore, the exemplary term "below" can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatially relative relationship descriptors used in the text are interpreted accordingly.

[0039] To solve the technical problem in the prior art of how to dynamically and accurately collect effective formation parameters during drilling, the present application provides a gamma sector discrimination method for near-bit, which can calculate the respective corresponding component coefficients through composite operations between standard positions. The calibration accuracy is improved, the error caused by component differences or installation errors of components during installation and debugging is avoided, the influence on the magnetic tool face is reduced, and the linearity and accuracy of the tool face are improved.

[0040] Figure 1 A gamma sector discrimination method for near-bit provided by an embodiment of the present application includes the following steps: Calculate the weight tool face according to the received accelerometer component values according to a preset rule; Calculate the magnetic tool face through calibration calculation according to the received magnetic component values of the magnetoresistive sensor and the component coefficients on the orthogonal three axes of the magnetic field according to a preset rule; Calculate the sector angle difference according to the difference between the weight tool face and the magnetic tool face; Correct the sector value according to the sector angle difference, and store the gamma values in different sectors according to the current sector value; Statistically calculate the sector duration and convert the pulse count into azimuth gamma data according to the set rules.

[0041] The following is a corresponding description in combination with specific embodiments. In the embodiments provided in the present application, first, the angular difference is initialized, and then the external signal is detected. If there is a change in the angular difference position, the angular difference is re-initialized. Determine the on / off pump state during drilling, confirm whether it is necessary to update the offset of the gravity tool face, and at the same time calculate the corrected magnetic component by collecting the magnetoresistive component in real time, so as to continuously update the position of the sector. On the premise of ensuring the gamma count and sector count, the azimuth gamma data is processed by sector respectively.

[0042] According to the processing process of the specific embodiment provided in the present application, the specific steps are as follows: (1) Obtain the initial angular difference according to the installation position: Since the sector discrimination circuit is arranged near the drill bit, the mechanical angular difference can be confirmed according to the initial position set by the sector discrimination circuit. After the installation position of the sector discrimination circuit near the drill bit changes, the initial angular difference is confirmed according to the actual installation position, and the angular difference position is directly written into the memory. In this way, the latest angular difference position can be obtained after each power-on, and this position is used for the calculation and update of the subsequent output angle. Among them, the calculation formula of the angular difference value is:

[0043] Where A is the actual angular difference value, i is the count of the sector value during detection, and 0, 1, 2, 3 represent different areas of the sector respectively. The lower computer system will directly determine the actual size of the angular difference according to the actual i value.

[0044] (2) Collect the gravity component, magnetic component, and gamma count: If the current state is the pump-off state, the component of the weight accelerometer is collected; if the current state is not the pump-off state, the three-axis components of the magnetoresistive sensor are collected in real time. The gamma count is started, and according to the current sector value, the gamma pulses are statistically calculated into the corresponding array. The rotation judgment circuit is used to collect the upper and lower gamma pulses, and the gamma counting logics of the two gamma pulses in the system are opposite. For example, if the sector counting process of the upper gamma is up, right, down, left, then the sector counting process of the lower gamma is down, left, up, right. The up, right, down, left in the sector counting process of the upper gamma respectively correspond to the above sector value i, that is, i at the upper position of the sector is recorded as 0, i at the right position is recorded as 1, i at the lower position is recorded as 2, and i at the left position is recorded as 3.

[0045] (3) Collect the magnetic component and perform correction calculation: During the process of near-bit drilling, magnetic component values are collected by each magnetoresistive sensor circuit and transmitted back to the system. Since there will be different installation errors for each magnetoresistive sensor during actual board mounting, debugging, and installation, and there will even be certain property differences between magnetoresistive sensors, it is necessary to obtain the component values of each axis of the magnetoresistive sensor on each axis of the geomagnetic field. The specific steps are as follows: Calculate the actual collected component values on the three axes :

[0046]

[0047]

[0048] Among them, h x 、h y 、h z are the numerical base offset component values corresponding to the actual component values of each axis, is the component coefficient of the actually collected magnetic component value on the three axes, is the magnetic component value of the actual magnetoresistive sensor on the orthogonal three axes.

[0049] Assume that the positive directions of the coordinate axes of the orthogonal magnetic field are X, Y, and Z respectively, and the negative directions are x, y, and z respectively. Then the data measured in the four directions of XYZ, xYz, xyZ, and Xyz are respectively recorded as H1 to H12. Theoretically, the components of the magnetoresistive component of a certain magnetoresistive sensor in the positive and negative directions of each orthogonal three axes are opposite to each other. Then, by adding the four data in the x and X directions, the components of each axis can be removed, and 4 times the base offset is retained. Therefore, the numerical base offset component values corresponding to the components of each axis can be calculated as:

[0050] By analogy with formula (5), h y 、h z ; Then, the components in the other positions of YxZ, YXz, yXZ, yxz, XzY, xZY, XZy, xyz, etc. are respectively recorded as H13 to H36. Similarly, the component coefficients of the actually collected magnetic component value on the three axes can be calculated as:

[0051] Among them, is the magnetic field component value of the Y axis of the orthogonal magnetic field; By analogy with formula (6), can be calculated; Through formulas (2), (3), and (4), the formula is obtained:

[0052] After transformation, we can get:

[0053] Where K is the coefficient matrix representation of the magnetoresistive component, is the transformed coefficient matrix, and M is the original magnetoresistive component. By calculating the original magnetoresistive component, the real-time corrected magnetic tool face can be obtained according to the magnetic tool face calculation formula.

[0054] (4) Calculate the output angle and sector update: If the current state is pump shutdown, the component information of the accelerometer and the magnetoresistive component information are collected. According to the collected component information, the gravity tool face can be directly calculated .

[0055] The gravity tool face has the following calculation formula:

[0056] Where θ is the angle value corresponding to the gravity tool face , and are the components collected by the accelerometer.

[0057] Given the magnetoresistive component, the magnetic tool face can be calculated using the following formula:

[0058] Where, is the angle value corresponding to the magnetic tool face , is the magnetic component after Z-axis correction, is the magnetic component after Y-axis correction.

[0059] By calculating the difference D between the gravity tool face and the magnetic tool face , the magnitude of this difference D is fixed after the installation of the sector discrimination circuit, and there will be a certain deviation value due to factors such as changes in environmental conditions (such as temperature or formation parameters, etc.) or errors in the installation location. To ensure the measurement accuracy, therefore, during each pump shutdown process, the angle difference needs to be updated again, that is:

[0060] After obtaining the magnetic tool face, according to the sector discrimination process, the radian value is used to distinguish the sector tool face, reducing the workload of the lower computer system calculation.

[0061] (5) Sector Counting and Gamma Statistics: In the embodiments provided in this application, the distinction between dynamic and static is represented by whether the gamma count in each sector is 0. If the gamma count in only one sector is not 0, it indicates that the current state is stationary; otherwise, it is in a rotating state. It is stipulated that 16s is taken as a cycle. During the duration of one cycle, the continuous duration when the gamma count in each sector is not 0 is statistically counted. If the gamma count in each sector is not 0, the continuous duration when the gamma count in the corresponding sector is not 0 is used to calculate the azimuth gamma; if the gamma count in each sector is 0, the duration of the entire cycle is used to calculate the azimuth gamma. According to the cumulative time of the continuous duration when the gamma count in each sector is not 0 and the cumulative value of the azimuth gamma in each sector, it is converted into pulse count seconds for output.

[0062] (6) Data Output: According to the instructions of the main module, after verification, the data output is completed in a question-and-answer manner.

[0063] This application provides a gamma sector discrimination method for near-bit. By processing the initial angular difference, the angular difference problem of the near-bit instrument itself is automatically processed. The difference between the gravity tool face and the magnetic tool face is collected through an external pump stop signal as the calibration offset. The free configuration of the angular difference is realized. If the installation position changes, the trouble in the disassembly and assembly process can be reduced.

[0064] Meanwhile, in this application, based on the theory that the components of the magnetoresistive sensor in the positive and negative directions of the standard magnetic field are opposite numbers, a certain magnetoresistive component is a linear accumulation of the axis components in the standard magnetic field. Through the composite operation between standard positions, the corresponding component coefficients can be calculated. The calibration accuracy is improved, the errors caused by component differences or the installation errors of components during installation and debugging are reduced, the influence on the magnetic tool face is reduced, and the linearity and accuracy of the tool face are improved.

[0065] According to the solution proposed in this application, the feasibility of this method is verified through experiments. In the experiments, the magnetoresistive calibration method of the calibration frame and the rotation test method are respectively adopted, and the effectiveness and accuracy of its sector discrimination are verified. Among them: (1) Magnetoresistive Calibration Method of the Calibration Frame: Please refer to Figure 2 、 Figure 3 、 Figure 4, after the hardware circuit debugging is completed, under the condition that the influence of the magnetic field environment is relatively small and stable, use a standard calibration frame to test the data of the circuit in the positive and negative directions of the X, Y, and Z axes of the standard magnetic field. Collect the corresponding magnetic group components around each axis in each quadrant, and obtain the corresponding magnetic group data after deduplication. Through composite calculation, the basic offset component value of the magnetic group and the corresponding magnetic group component coefficient are obtained. Through formula derivation and transformation, the corresponding calculation parameters are obtained. Then, select several random azimuths and well inclinations at the calibration site for rotation testing. The linearity of the final magnetic tool face is good and meets the use requirements.

[0066] (2) Rotation test experiment: Please refer to Figure 5 , Figure 6 , in order to verify the effectiveness of a gamma sector discrimination method for near-bit provided in the embodiments of the present application, the circuit is encapsulated in a skeleton and rotated on a rotation test fixture to test the linearity of the magnetic tool face. Then, two gamma sensors are used for rotation testing at the same time, and interference testing is carried out using a radiation welding rod. Finally, the obtained effect meets the requirements. During the test, first perform a static test for a period of time, and then rotate the radiation welding rod close to the lower sector at a speed of 80 rpm. The corresponding output gamma curve also increases accordingly, determining that the method provided in the embodiments of the present application for azimuth gamma discrimination meets the actual design requirements.

[0067] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0068] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0069] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0070] In this application, unless otherwise clearly defined or limited, terms such as "installed", "connected", "linked", "fixed", etc. shall be understood in a broad sense. For example, it can be a connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0071] In this application, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features between them. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0072] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0073] Obviously, those skilled in the art can make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, provided that these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, this application also intends to include these changes and modifications.

[0074] As described above, this is the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

1. A gamma fan zone resolution method for near-bit, characterized in that, It includes the following steps: Calculate the weight tool face according to the received gravitational accelerometer components according to a preset rule; Perform correction calculation according to a preset rule based on the received magnetic component value of the magnetoresistive sensor and the component coefficients of the magnetic component value on the orthogonal three axes of the magnetic field to obtain the magnetic tool face; Calculate the sector angle difference according to the difference between the weight tool face and the magnetic tool face; Correct the sector value according to the sector angle difference, and store the gamma values in different partitions according to the current sector value; Statistically calculate the sector duration, and convert the pulse count into azimuth gamma data according to the set rules.

2. The gamma ray fan zone resolution method for near-bit according to claim 1, wherein, Before receiving the gravitational accelerometer components, the magnetic component value of the magnetoresistive sensor, and the component coefficients, it is necessary to obtain the angle difference each time the device is powered on. The specific steps for obtaining the angle difference include: confirming the initial angle difference according to the position of the sector discrimination circuit in the corresponding sector, and obtaining the latest angular position each time it is powered on again. The calculation formula for the angle difference is: Where: A is the actual angle difference, i is the count of the sector value during detection, and 0, 1, 2, and 3 respectively represent different regions of the sector.

3. The gamma ray sector discrimination method for near-bit according to claim 1, characterized in that, The specific state judgment and receiving steps for receiving the gravitational accelerometer components, the magnetic component value of the magnetoresistive sensor, and the component coefficients include: if the current state is the pump stop state, then receive the components of the weight accelerometer; if it is not in the pump stop state, then receive the three-axis components of the magnetoresistive sensor; obtain the specific sector value through processing based on the three-axis components, and then count the gamma pulses into different sectors.

4. The gamma sector resolution method for near-bit according to claim 1, characterized in that The specific steps for obtaining the component coefficients of the magnetic component value of the received magnetoresistive sensor on the orthogonal three axes of the magnetic field and the original magnetoresistive component value include: Calculate the actual acquisition component values on three axes : Among them, h x , h y , h z are the numerical base offset component values corresponding to the actual axis components, is the component coefficient of the actually collected magnetic component values on the three axes, is the magnetic component value of the actual magnetoresistive sensor on the orthogonal three axes; Assume that the positive directions of the coordinate axes of the orthogonal magnetic field are X, Y, and Z respectively, and the negative directions are x, y, and z respectively. Then the data measured in the four directions of XYZ, xYz, xyZ, and Xyz are respectively recorded as H1 to H12. The calculated numerical basic offset component values corresponding to the components of each axis are: The analog formula (5) can be used to calculate h y , h z ; Then measure the components in the remaining positions YxZ, YXz, yXZ, yxz, XzY, xZY, XZy, xyz, etc., which are respectively recorded as H13 to H36. The measured component coefficients of the actually collected magnetic component value on the three axes are: Among them, is the magnetic field component value of the orthogonal magnetic field along the Y-axis; It can be calculated by analogy with formula (6). By analogy with formulas (2), (3), and (4), the formula is obtained: After transformation, it can be obtained: where K is the coefficient matrix representation of the magnetoresistance component, is the converted coefficient matrix, M is the original magnetoresistance component, is the numerical base offset component matrix corresponding to the actual components of each axis, and H is the magnetoresistance component matrix actually collected by the magnetoresistance sensor.

5. The gamma ray sector discrimination method for near-bit according to claim 1, characterized in that, Before calculating the sector angle difference based on the difference between the weight tool face and the magnetic tool face, if the current state is pump-off, collect the component information of the accelerometer and the magnetic component value information of each magnetoresistive sensor, and calculate the weight tool face and the magnetic tool face , and calculate the difference D through the weight tool face and the magnetic tool face . The calculation formula is: Use the difference D as the offset of the weight tool face.

6. The gamma ray sector discrimination method for near-bit according to claim 5, characterized in that, The said gravity tool face The calculation formula is as follows: where θ is the gravity tool face corresponding angular value and are the components collected by the gravity accelerometer.

7. The gamma ray fan zone resolution method for near-bit according to claim 5, characterized in that, The described magnetic tool face The calculation formula is as follows: Among them, is the angle value corresponding to the magnetic tool face , is the magnetic component after Z-axis correction, is the magnetic component after Y-axis correction.

8. The gamma ray fan zone resolution method for near-bit according to claim 1, characterized in that, The specific steps for statistically calculating the sector duration and converting the pulse count into azimuth gamma data include: stipulating a specific time as the period. During the duration of one period, statistically calculate the continuous duration when the gamma count in each sector is not 0. If the gamma count in each sector is not 0, then use the continuous duration when the gamma count in each sector is not 0 to calculate the azimuth gamma; if the gamma count in each sector is 0, then use the duration of the entire period to calculate the azimuth gamma; convert it into pulse count seconds for output according to the cumulative time of the continuous duration when the gamma count in each sector is not 0 and the cumulative value of the azimuth gamma in each sector.

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