Directional drilling construction method

Abstract

The invention relates to a directional drilling construction method, which belongs to the technical field of construction drilling, and comprises the following steps: arranging closed wire coils on two sides of a crossing center line to form an artificial magnetic field; calibrating along the crossing center line to obtain a direction control azimuth angle before the equipment enters the field; during drilling of each drill rod, a probe is used for detecting the artificial magnetic field and the geomagnetic field so as to obtain the current azimuth angle of the drill bit; acquiring a deviation angle of the drill bit based on the current azimuth angle and the direction control azimuth angle; and on the basis of the deviation angle, the actual advancing direction of the next drill rod is obtained, and drilling is completed according to the actual advancing direction. The artificial magnetic field effectively shields the disturbance of external interference sources such as underground metal obstacles and high-voltage lines on the geomagnetic field, and reduces the risk of path deviation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of construction drilling, and in particular to a directional drilling construction method. BACKGROUND

[0002] Traditional pipeline construction often requires large-scale excavation on the ground. Although this method is intuitive, it can seriously interfere with traffic and affect residents' daily travel in urban environments. At the same time, the construction period is long and is easily affected by changes in the underground environment.

[0003] More deeply, this method lacks fine control of the construction process and is difficult to adapt to the dual demands of environmental protection and efficiency in modern cities. In particular, when faced with unknown obstacles or complex underground environments, it often appears to be inadequate.

[0004] The guide hole is the initial path of pipeline laying, and the accuracy of its direction and trajectory directly determines the quality of subsequent pipeline installation. If the direction of the guide hole deviates, it will lead to the pipeline being unable to be laid according to the designed path, and even may need to be reworked, increasing the cost and time. More complexly, the control of the guide hole is often disturbed by external environments, such as underground metal objects or ground high-voltage lines, which can disturb the direction judgment and cause the path to deviate. Such interference not only affects the construction precision, but also can cause greater engineering risks in subsequent steps.

[0005] Therefore, how to ensure the accurate control of the direction of the guide hole in a complex environment and effectively deal with the influence of external interference on path judgment has become a key problem that needs to be solved in current pipeline construction. This problem is directly related to the success or failure of the entire project, and is also the core of achieving efficient and environmentally friendly construction in urban environments. SUMMARY

[0006] The embodiments of the present application provide a directional drilling construction method to solve the problem that in the related art, the deviation of the direction of the guide hole will lead to the pipeline being unable to be laid according to the designed path, affecting the construction precision and causing greater engineering risks.

[0007] In a first aspect, a directional drilling construction method is provided, in which a closed loop of guide wires is laid on both sides of a center line to form an artificial magnetic field; a control direction azimuth angle before a device enters a field is obtained by marking along the center line; when each drill rod is drilled, a probe is used to detect the artificial magnetic field and the geomagnetic field to obtain a current azimuth angle of a drill bit; based on the current azimuth angle and the control direction azimuth angle, a deviation angle of the drill bit is obtained; based on the deviation angle, an actual travel azimuth of a next drill rod is obtained, and drilling is completed according to the actual travel azimuth.

[0008] In some embodiments, before laying the closed loop of the conductor on both sides of the crossing center line, the construction method further comprises: installing a drilling machine at the starting point of the crossing center line; installing and debugging a steering system on the drilling machine; and obtaining a steering reference of the drilling machine based on the steering system.

[0009] In some embodiments, installing the drilling machine at the starting point of the crossing center line comprises: obtaining an initial positioning point of the drilling machine based on a crossing angle into the earth and a drilling machine size parameter; obtaining a positioning deviation of the drilling machine after positioning based on the crossing center line and the initial positioning point; determining whether the positioning deviation meets a positioning design requirement; if not, repeatedly moving the drilling machine to position and measuring the positioning until the drilling machine meets the positioning design requirement after positioning; otherwise, installing the drilling machine at the initial positioning point.

[0010] In some embodiments, when the drilling machine meets the positioning design requirement after positioning, the drilling machine is anchored by an anchor rod.

[0011] In some embodiments, obtaining the steering reference of the drilling machine based on the steering system comprises: placing and calibrating a probe along the crossing center line; measuring a plurality of sets of steering parameters along the crossing center line using the probe; comparing the plurality of sets of steering parameters, and selecting one set of steering parameters as the steering reference of the drilling machine according to a comparison result.

[0012] In some embodiments, calibrating the steering azimuth angle before the equipment enters the field along the crossing center line comprises: measuring a plurality of sets of first calibration steering azimuth angles along the crossing center line using a detector carrying a non-magnetic drill rod; obtaining a first preliminary steering azimuth angle based on the plurality of sets of first calibration steering azimuth angles; measuring a plurality of sets of second calibration steering azimuth angles along the crossing center line using the detector; obtaining a second preliminary steering azimuth angle based on the plurality of sets of second calibration steering azimuth angles; and obtaining the steering azimuth angle based on the first preliminary steering azimuth angle and the second preliminary steering azimuth angle.

[0013] In some embodiments, obtaining the steering azimuth angle based on the first preliminary steering azimuth angle and the second preliminary steering azimuth angle comprises: obtaining an azimuth deviation based on the first preliminary steering azimuth angle and the second preliminary steering azimuth angle; determining whether the azimuth deviation meets a steering design requirement; if so, taking the first preliminary steering azimuth angle as the steering azimuth angle; otherwise, re-obtaining the first preliminary steering azimuth angle and the second preliminary steering azimuth angle until the azimuth deviation meets the steering design requirement.

[0014] In some embodiments, obtaining the actual running azimuth of the next drill rod based on the deviation angle comprises: determining whether the deviation angle meets a drilling design requirement; if not, withdrawing the drill rod that has passed through the magnetic field interference area, and correcting the current azimuth angle based on the deviation angle to obtain the actual running azimuth of the next drill rod; otherwise, taking the current azimuth angle as the actual running azimuth of the next drill rod.

[0015] In some embodiments, the drill pipe is controlled to drill multiple times based on the deviation angle, and the adjustment angle of the drill hole is controlled to be no more than the deviation angle during each drilling.

[0016] In some embodiments, the cumulative deviation angle value of each drill pipe is less than the design deviation value during drilling of each drill pipe.

[0017] The beneficial effects brought by the technical solutions provided in the application include: The application provides a directional drilling construction method, which comprises the following steps: arranging a closed loop of guide wires on both sides of a center line in advance to form a stable and controllable artificial magnetic field environment as an absolute reference datum in a construction process; calibrating a control direction azimuth angle of a device before entering the site before construction; detecting a relative relationship between the artificial magnetic field and the geomagnetic field in real time and synchronously by a probe during drilling to accurately obtain a current azimuth angle of a drill bit; comparing the current azimuth angle with a preset control direction azimuth angle to calculate a deviation angle of the drill bit; generating a corrected travel azimuth of a next drill pipe based on the deviation angle and guiding the drill pipe to accurately advance along the corrected azimuth to ensure that the guide hole strictly follows a design trajectory. The artificial magnetic field effectively shields external interference sources such as underground metal obstacles and high-voltage lines from disturbing the geomagnetic field, thereby reducing the risk of path deviation. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The overall flowchart provided by the embodiments of the application is shown in the figure. Figure 2 The flowchart provided by the embodiments of the application for showing steps S10, S11 and S12 is shown in the figure. Figure 3 The detailed flowchart provided by the embodiments of the application for showing step S1 is shown in the figure. Figure 4 The detailed flowchart provided by the embodiments of the application for showing step S2 is shown in the figure. Figure 5 The detailed flowchart provided by the embodiments of the application for showing step S5 is shown in the figure. DETAILED DESCRIPTION To make the purposes, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0020] The embodiments of the present application provide a directional drilling construction method, which can solve the problem that in the prior art, deviation of the direction of a guide hole leads to failure of pipeline laying according to a designed path, affects construction precision, and causes greater engineering risk.

[0021] With reference to Figures 1-5 A directional drilling construction method comprises the following steps. S1: A closed loop of wires is laid on both sides of a crossing center line to form an artificial magnetic field. The closed loop of wires is laid as follows: a surveying instrument, including but not limited to a total station, is used to lay a closed loop of wires on both sides of a pipeline crossing center line, and an artificial magnetic field is formed after power is supplied, to review control direction parameters. The artificial magnetic field can be free from interference of any external magnetic field, and accurately reflects a specific position of a drill bit. Actual application of the artificial magnetic field can ensure that an actual excavation point is within a designed excavation point range, and lays a good foundation for smooth back dragging of the pipeline.

[0022] S2: A control direction azimuth angle before entry of an acquisition device is calibrated along the crossing center line. External magnetic fields are mainly generated by underground pipelines, underground optical cables, rigid buildings, large ships, and overhead high-voltage lines, which will affect geomagnetic field strength and geomagnetic angle, and thus affect the control direction azimuth angle. Therefore, the control direction azimuth angle is measured after measurement and laying of a line in the case of no external magnetic field interference in a construction site, because all construction devices will interfere with the azimuth angle.

[0023] The application obtains the control azimuth angle before the entry of the calibration acquisition device along the crossing center line, including: first, using the detector to measure a plurality of first calibration control azimuth angles along the crossing center line with the non-magnetic drill pipe, specifically, in the construction site, the azimuth angle can be measured by using a single bucket excavator, the detector is loaded into the non-magnetic drill pipe, and a plurality of measuring points are measured along the crossing center line at the entry and exit points, at least 10 measuring points, and each measuring point includes a set of calibration control azimuth angle; based on the plurality of first calibration control azimuth angles, a first preliminary control azimuth angle is obtained, that is, the average value of the plurality of first calibration azimuth angles is calculated, and the average value is taken as the first preliminary control azimuth angle. Then, using the detector to measure a plurality of second calibration control azimuth angles along the crossing center line, specifically: the detector is taken out of the non-magnetic drill pipe, and the control azimuth angle is directly measured by using the detector alone, and the measured data is the plurality of second calibration control azimuth angles. Further based on the plurality of second calibration control azimuth angles, a second preliminary control azimuth angle is obtained, and the average value of the plurality of second calibration azimuth angles is also calculated, and the average value is taken as the second preliminary control azimuth angle. Finally, based on the first preliminary control azimuth angle and the second preliminary control azimuth angle, the control azimuth angle is obtained.

[0024] The application obtains the control azimuth angle based on the first preliminary control azimuth angle and the second preliminary control azimuth angle, including: S20: based on the first preliminary control azimuth angle and the second preliminary control azimuth angle, a deviation in azimuth is obtained, that is, the difference between the first preliminary control azimuth angle and the second preliminary control azimuth angle is calculated, and the obtained value is taken as the deviation in azimuth. If there is no external magnetic field interference in the site, the difference between the two measured first preliminary control azimuth angles and the second preliminary control azimuth angle should be within the allowable range, if the difference is large, it must be measured again. And it should be noted that when measuring the azimuth angle, the front end and the rear end of the detector must coincide with the crossing center line to ensure the correctness of the measured azimuth angle.

[0025] S21: therefore, after obtaining the deviation in azimuth, it is judged whether the deviation in azimuth meets the control design requirement; if yes, the first preliminary control azimuth angle is taken as the control azimuth angle; otherwise, the first preliminary control azimuth angle and the second preliminary control azimuth angle are reacquired until the deviation in azimuth meets the control design requirement.

[0026] When measuring the control azimuth angle, it should be noted that in the case where the single bucket excavator cannot cooperate, the control parameter is directly measured by using the detector, the detector must be completely placed on the crossing center line, a place far away from the external magnetic field interference source is selected on the crossing center line, and more than 10 data are measured at different positions at the entry and exit points, the average value is taken when the difference is small, and the reason is analyzed and re-measured when the difference is large.

[0027] S3: After obtaining the steering azimuth angle through actual measurement, make original record. Then, in the subsequent steps, use the probe to detect the artificial magnetic field and the geomagnetic field to obtain the current azimuth angle of the drill bit every time the drill pipe is drilled. The specific method is as follows: in the drilling process, the probe collects vector data of the artificial magnetic field and the geomagnetic field in real time, and the current azimuth angle of the drill bit is obtained through the calculation of the magnetometer.

[0028] S4: Based on the current azimuth angle and the steering azimuth angle, obtain the deviation angle of the drill bit. The deviation angle is the difference between the current azimuth angle and the steering azimuth angle. S5: After obtaining the deviation angle, based on the deviation angle, obtain the actual running direction of the next drill pipe, and complete the drilling according to the actual running direction, that is, the running direction of the next drill pipe is automatically compensated to the left: if the deviation angle is negative, it is compensated to the right, realizing the "measurement-calculation-adjustment" closed loop.

[0029] In this application, based on the deviation angle, the actual running direction of the next drill pipe is obtained, which includes: S50: First, determine whether the deviation angle meets the drilling design requirements, which include but are not limited to the deviation of the guide hole at the soil outlet point within 1m of the design soil inlet point, that is, to ensure that the offset of each drill pipe is within the allowed range, and the cumulative value cannot exceed 1m; if not, the drill pipe passing through the magnetic field interference zone is extracted, and the current azimuth angle is corrected based on the deviation angle to obtain the actual running direction of the next drill pipe; otherwise, the current azimuth angle is taken as the actual running direction of the next drill pipe. It should be noted that when the current azimuth angle is corrected based on the deviation angle, the drill pipe is controlled to drill multiple times, and the adjustment angle of the drill hole is controlled to be no more than the deviation angle each time.

[0030] When the drill bit drills out of the magnetic field interference zone, the actual deviation angle is obtained in real time through the artificial magnetic field, the drill pipe section affected after the interference zone is immediately extracted, and the correction azimuth angle is calculated based on the deviation angle. Then, the multiple fine adjustment strategy is adopted when re-drilling to ensure smooth transition of the trajectory. In combination with the actual construction scene, it is understood that in a 2.8km pipeline engineering, the drill bit drills out of the interference zone and measures the offset of 0.78m, only extracts the drill pipe of 3m after the interference zone, and re-drills 3m with 0.08° each time, so that the cumulative deviation of the guide hole trajectory and the design curve is accurately zeroed from 0.92m to 0.03m, avoiding the whole section of rework.

[0031] In this application, before laying the closed guide loop on both sides of the center line, the construction method further includes: S10: installing the drilling machine at the starting point of the crossing center line, specifically comprising: first, based on the crossing into the earth angle and the drilling machine size parameters, obtaining the initial positioning point of the drilling machine, specifically: according to the design disclosure and construction drawings, using the GPS positioning system combined with the total station, laying out the drilling field control line and the equipment placement position line, ensuring that the drilling center line and the into-the-earth point and the out-of-the-earth point are in a straight line, and making good mark piles along the way. The drilling machine is installed at the into-the-earth point and is on the same axis as the out-of-the-earth point, with a left-right error of not more than 100 mm, and the drilling machine into-the-earth angle is -25°. After obtaining the initial positioning point of the drilling machine, mark it with lime or a string, and use it as the basis for positioning the drilling machine. Then, based on the crossing center line and the initial positioning point, obtain the positioning deviation of the drilling machine after positioning. The positioning deviation is obtained based on the measurement instrument. Finally, determine whether the positioning deviation meets the positioning design requirements. The positioning design requirements are that the angle deviation of the drilling machine positioning direction relative to the crossing center line is not more than 0.1. If it does not meet the requirements, repeat the positioning and measurement of the drilling machine until the drilling machine meets the positioning design requirements after positioning. Otherwise, install the drilling machine at the initial positioning point. When the drilling machine meets the positioning design requirements, anchor the drilling machine using anchor rods. The drilling machine anchoring method includes but is not limited to: building a 4.3m x 2.2m pool wall on the cushion layer of the anchor box foundation pit with bricks, and pouring concrete between the pool wall and the surrounding soil. The steel anchor box is hoisted into the anchor pit. When constructing, lay a 36mm steel plate with a cushion δ=20mm under the drilling machine. The steel plate and the anchor box are connected and welded with 16mm channel steel. Then, position the drilling machine main machine, connect the anchor box, mud system, drill pipe, and power source. Connect various hydraulic pipelines, mud pipelines, and control cables, etc.

[0032] S11: After the drilling machine is completely assembled, carefully check and confirm, and then perform a trial run of the equipment. That is, install and debug the control direction system on the drilling machine. Adjust the control direction system to ensure that the measurement data is stored in the computer. Then, based on the control direction system, obtain the control direction reference of the drilling machine, specifically comprising: placing and calibrating the probe along the crossing center line; then using the probe to measure multiple sets of control direction parameters along the crossing center line, selecting at least three different positions, and rotating and measuring at least 4 times at each position, and making good records; finally, compare multiple sets of control direction parameters, and select one set from the multiple sets of control direction parameters as the control direction reference of the drilling machine according to the comparison result.

[0033] After the drilling machine is assembled, perform a systematic trial run to eliminate equipment failure risks. The trial run can be calibrated in advance to avoid loss of control due to equipment failure during drilling. The geomagnetic field is affected by small-scale interference (such as ground metal debris). Three-point and four-time measurement can eliminate accidental errors. Compare all data and select the set with the smallest fluctuation to ensure that the reference value is true and reliable.

[0034] The implementation principle of the embodiment of the present application is: laying closed conductor loops on both sides of the center line to form an artificial magnetic field as an absolute reference benchmark not affected by external interference, thereby fundamentally eliminating the influence of underground metal pipelines, high-voltage lines and other magnetic field interference sources. In the drilling rig positioning link, through accurate calculation based on the angle of entry into the earth and the size parameters of the drilling rig, combined with repeated measurement and adjustment, the drilling rig is ensured to strictly coincide with the center line of the crossing center; the anchoring link adopts anchor rod fixation to prevent the drilling rig from shifting during drilling. In the control direction benchmark establishment link: first, a non-magnetic drill rod carries a detector to measure multiple points along the crossing center line to obtain a first preliminary control direction azimuth, and then a separate detector is used to measure a second preliminary control direction azimuth, and the final control direction benchmark is determined after comparison between the two, thereby avoiding measurement distortion caused by interference after the equipment enters the site. During drilling, the probe detects the artificial magnetic field and the geomagnetic field in real time to accurately obtain the current azimuth, and the system dynamically calculates the deviation angle: if the cumulative deviation approaches the design limit, only the affected drill rod section behind the magnetic field interference area is extracted, and fine adjustment is performed based on the deviation angle to make the trajectory smoothly return to the design curve; if the deviation is within the allowable range, the current azimuth is continued to be used for drilling to ensure that the cumulative deviation of each drill rod is always less than the design value.

[0035] The scheme is exemplified in actual engineering: the traditional method causes an error of 0.85 meters at the earth exit point due to magnetic field interference, and has a high rework rate; the artificial magnetic field of the scheme accurately identifies a drill bit deviation of 0.78 meters, only 3 meters of drill rod behind the interference area is extracted, and fine adjustment of 0.08° / time is performed to re-drill 3 meters, so that the cumulative deviation is returned to 0.03 meters from 0.92 meters. The effect of the scheme is reflected in: improved accuracy, improved efficiency, reduced mud waste, improved reliability, and solving the problem of trajectory loss of control caused by magnetic field interference.

[0036] In the description of the present application, it should be noted that the positions or position relationships indicated by the terms "upper", "lower", etc. are based on the positions or position relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the connection between two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] It should be noted that, in the present application, the relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0038] The foregoing is merely illustrative of the principles of the application and various modifications can be made by those skilled in the art without departing from the spirit and scope of the application. The above embodiments are illustrative, and not restrictive, of the scope of the application.

Claims

1. A method of directional drilling construction, characterised in that, It comprises: Laying closed conductor loops on both sides of the crossing center line to form an artificial magnetic field; Calibrating the control orientation azimuth of the acquisition equipment before entering the field along the crossing center line; Using a probe to detect the artificial magnetic field and the geomagnetic field when each drill rod is drilled to obtain the current azimuth of the drill bit; Based on the current azimuth and the control orientation azimuth, the deviation angle of the drill bit is obtained; Based on the deviation angle, the actual travel azimuth of the next drill rod is obtained, and drilling is completed according to the actual travel azimuth.

2. A method of directional drilling according to claim 1 wherein: Before laying closed conductor loops on both sides of the crossing center line, the construction method further comprises: Installing a drilling machine at the starting point of the crossing center line; Installing and debugging the control orientation system on the drilling machine; Based on the control orientation system, the control orientation reference of the drilling machine is obtained.

3. A method of directional drilling according to claim 2 wherein: Installing a drilling machine at the starting point of the crossing center line comprises: Based on the crossing into the earth angle and the drilling machine size parameters, the initial installation point of the drilling machine is obtained; Based on the crossing center line and the initial installation point, the installation deviation of the drilling machine after installation is obtained; Determine whether the installation deviation meets the installation design requirements; If not, repeat the movement of the drilling machine installation and installation measurement until the drilling machine installation meets the installation design requirements after installation; Otherwise, install the drilling machine at the initial installation point.

4. A method of directional drilling according to claim 3 wherein: When the drilling machine meets the installation design requirements, anchor the drilling machine with anchor rods.

5. A method of directional drilling according to claim 2, wherein: Based on the control orientation system, the control orientation reference of the drilling machine is obtained, comprising: Placing and calibrating the probe along the crossing center line; Using the probe to measure multiple sets of control orientation parameters along the crossing center line; Compare multiple sets of control orientation parameters, and select one set of control orientation parameters as the control orientation reference of the drilling machine according to the comparison result.

6. A method of directional drilling according to claim 1, wherein: Calibrating the control orientation azimuth of the acquisition equipment before entering the field along the crossing center line comprises: Using a probe to carry a non-magnetic drill rod along the crossing center line to measure multiple sets of first calibration control orientation azimuth; Based on multiple sets of first calibration control orientation azimuth, a first preliminary control orientation azimuth is obtained; Using a probe to measure multiple sets of second calibration control orientation azimuth along the crossing center line; Based on multiple sets of second calibration control orientation azimuth, a second preliminary control orientation azimuth is obtained; Based on the first preliminary control orientation azimuth and the second preliminary control orientation azimuth, the control orientation azimuth is obtained.

7. A method of directional drilling according to claim 6 wherein: Based on the first preliminary control orientation azimuth and the second preliminary control orientation azimuth, the control orientation azimuth is obtained, comprising: Based on the first preliminary control orientation azimuth and the second preliminary control orientation azimuth, the azimuth deviation is obtained; Determine whether the azimuth deviation meets the control orientation design requirements; If so, the first preliminary control orientation azimuth is taken as the control orientation azimuth; Otherwise, reacquire the first preliminary control orientation azimuth and the second preliminary control orientation azimuth until the azimuth deviation meets the control orientation design requirements.

8. A method of directional drilling according to claim 1 wherein: Based on the deviation angle, the actual travel azimuth of the next drill rod is obtained, comprising: Determine whether the deviation angle meets the drilling design requirements; If not, the drill rod passing through the magnetic field interference area is pulled out, and the current azimuth is corrected based on the deviation angle to obtain the actual travel azimuth of the next drill rod; Otherwise, the current azimuth is taken as the actual travel azimuth of the next drill rod.

9. A method of directional drilling according to claim 8 wherein: When correcting the current azimuth based on the deviation angle, control the drill rod to drill multiple times, and the adjustment angle of the drill hole is controlled to be not more than the deviation angle each time.

10. A method of directional drilling according to claim 1 wherein: The accumulated deviation angle value of each drill pipe is less than the design deviation value when each drill pipe is drilled. The accumulated deviation angle value of each drill pipe is less than the design deviation value when each drill pipe is drilled.

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