A side-drilling device and process for reconstructing a channel in an abandoned well without access.

Abstract

This invention discloses a sidetracking device and process for reconstructing accompanying channels in abandoned wells without access routes, specifically relating to the field of oil and gas well workover technology. It includes a tubing string, inside which a drill pipe is installed. A gyroscope is fixedly connected to the bottom of the drill pipe, and a feed rod is fixedly connected to the bottom of the gyroscope. A directional drilling device is fixedly connected to the bottom of the inner cavity of the tubing string. This invention's sidetracking device and process for reconstructing accompanying channels in abandoned wells without access routes significantly improves window opening efficiency and directional drilling accuracy by optimizing the parameters of casing windowing and accompanying wellbore directional drilling. The high-hardness material of the composite milling cone ensures the regularity and durability of the window. The combined use of a low-bend screw motor and a roller cone drill makes the directional drilling process smoother and more precise. This solution not only reduces drilling costs but also effectively reduces construction risks, providing a solid foundation for subsequent sidetracking operations.

Description

Technical Field

[0001] This invention relates to the field of oil and gas well workover technology, and in particular to a sidetracking device and process for reconstructing an accompanying channel in an abandoned well without access. Background Technology

[0002] In recent years, with the extension of oilfield development lifespan, some challenging wells, such as those with misaligned casing lacking access, complex debris that is difficult to retrieve, or those experiencing sand and rock outbursts, face significant challenges in well repair using techniques like debris retrieval and milling. These repairs are difficult, time-consuming, costly, and have a low success rate. In some cases, they may even wear through the casing, rendering the original well unusable for engineering abandonment. Therefore, there is an urgent need to research new technologies to reduce the termination rate of major workovers and improve the quality of well abandonment.

[0003] The same-well side-drilling directional re-entry technology can utilize the wellbore of a well to be abandoned, and side-drill to form an accompanying wellbore within 30cm of the original wellbore. Bypassing the well section blocked by misalignment, leakage, and falling objects, a window is opened outside the pipe at an appropriate location before re-entering the original wellbore. After injecting plugging agent into the original wellbore, it is completely sealed and abandoned. It can also be applied to wellbore rescue and emergency treatment, re-entry and sealing of abandoned wells in gas storage facilities, etc., bringing new technical methods to the abandonment of difficult oil and gas well projects. Summary of the Invention

[0004] The technical problem to be solved by this invention is to drill a new wellbore through a window opening on the original well casing for wells that cannot be repaired or abandoned using the original wellbore channel. By using passive magnetic guidance technology and precise drilling trajectory control technology, an accompanying wellbore within 30cm of the original well casing is formed, bypassing the well section blocked by misalignment or falling objects. A window is opened on the outside of the casing at the designed position, and then the original wellbore is re-entered. After the original wellbore is injected with plugging agent, it is completely sealed and abandoned.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A sidetracking device and process for reconstructing an accompanying passage in a decommissioned well without access, comprising the following steps:

[0007] S1. Original casing side drilling window opening: Drill rod with directional tool to the window opening position, measure and adjust the orientation and then mount the directional tool, drill rod with compound milling cone to mill the inner wall of casing to form window;

[0008] S2. Accompanying wellbore build-up: Drill with the drill pipe and bottom directional tool string at a build-up rate of <0.5° / m, and build up to a horizontal displacement of 5m;

[0009] S3. Use magnetic ranging to guide side-drilling with the wellbore: Install the kit at the bottom of the drill pipe, use the magnetic directional rangefinder to measure the distance and azimuth, and guide the side-drilling with the wellbore to bring the inclined tubing string close to the tubing string, maintaining a lateral distance of 30cm or less.

[0010] S4. External window opening: Use a turbine-type external window opening tool to mill the pipe column to form a window;

[0011] S5. Cement sealing and scrapping: Insert an oil pipe into the first tubing string and squeeze cement into the ash injection tubing string to achieve sealing and scrapping.

[0012] Preferably, in step S1, the composite milling tap is made of diamond composite teeth with a hardness of 85-93 HRA, and the window drilling parameters are a displacement of 800 LPM, a rotation speed of 100-120 RPM, a working torque of ≤500 ftlbs, a drilling pressure of 5-20 KN, and the drill pipe is 2-7 / 8 inches in size.

[0013] Preferably, in step S3, the magnetic guide rangefinder is used to measure the distance and orientation relationship between the magnetic ranging-side drilling accompanying wellbore pipe one and the tubing string one, guiding the accompanying wellbore to approach the tubing string one and maintain a lateral distance of 30cm or less.

[0014] Preferably, step S41 is added after step S4:

[0015] S41: Optimize external pipe opening: Utilize an intelligent control system to monitor the working status of the turbine-type external pipe opening tool in real time, and automatically adjust the cutting angle and rotation speed of the milling drill bit to ensure the regularity of the window and the efficiency of opening.

[0016] The intelligent control system monitors the torque and drilling pressure of the milling drill bit through sensors, and dynamically adjusts the rotation speed and drilling fluid discharge of the turbine-type external casing opening tool to adapt to casings of different thicknesses.

[0017] In addition, the present invention also discloses a sidetracking device for rebuilding an accompanying channel in a decommissioned well without a channel, including a tubing string one, a drill pipe inside the tubing string one, a drilling gyroscope measuring instrument one fixedly connected to the bottom of the drill pipe, an input rod fixedly connected to the bottom of the drilling gyroscope measuring instrument one, an inclination device fixedly connected to the bottom of the inner cavity of the tubing string one, an installation kit provided at the connection between the drill pipe and the drilling gyroscope measuring instrument one, and a casing window tubing string, a sidetracking accompanying wellbore inclination tubing string, a magnetic ranging-sidetracking accompanying wellbore tubing one, and a magnetic ranging-sidetracking accompanying wellbore tubing two, which are adapted to the bottom of the installation kit, and a cement sealing tubing string provided at the bottom of the magnetic ranging-sidetracking accompanying wellbore tubing two.

[0018] Preferably, the sleeve windowing column includes a weight rod, the bottom of which is fixedly connected to a low-speed screw motor, and the bottom of which is fixedly connected to a composite milling cone, which includes a window opening milling cone and a window repair milling cone, used to mill the inner wall of the sleeve to form a window and repair the window.

[0019] Preferably, the side-drilling accompanying wellbore skew string includes a second drilling gyroscope measuring instrument, the bottom of which is equipped with a low-angle screw motor, and the bottom of the low-angle screw motor is rotatably connected to a roller cone drill. The low-angle screw motor is used to output rotational power, and the roller cone drill is used to cut the formation, drilling with a dogleg angle of <0.5° / m, and creating an skew to a horizontal displacement of 5m.

[0020] The low-angle screw motor has an outer diameter of 79-146mm, a power of 36-75HP, a torque of 1200-2600NM, and a working displacement of 10-30L / s.

[0021] Preferably, the magnetic ranging-side drilling accompanying wellbore pipe one includes a magnetic guide rangefinder, the bottom of which is fixedly connected to a drilling gyroscope measuring instrument three, the bottom of which is fixedly connected to a low-bend angle screw motor two, the output end of which is connected to a roller cone drill two, the magnetic guide rangefinder is used to measure the distance and azimuth relationship between the magnetic ranging-side drilling accompanying wellbore pipe one and the tubing string one, and guide the accompanying wellbore to approach the tubing string one, maintaining a lateral distance of 30cm or less.

[0022] Preferably, the magnetic ranging-side drilling accompanying well casing includes a drilling gyroscope measuring instrument four, a turbine-type external casing window opening tool, and a milling drill bit. The bottom of the drilling gyroscope measuring instrument four is provided with a turbine-type external casing window opening tool, and the bottom of the turbine-type external casing window opening tool is connected to a milling drill bit. The turbine-type external casing window opening tool is used to open a window outside the casing, and the milling drill bit is used to grind the casing.

[0023] The cement sealing tubing includes an oil pipe, a packer, and a one-way valve. The one-way valve has a guide at its bottom and is connected to a cement injection tubing. The cement injection tubing is filled with cement and is used to inject cement. The packer is used to seal the annulus and the one-way valve is used to prevent cement from flowing back up.

[0024] The outer diameter of the tools of the drilling gyroscope measuring instruments I, II, III and IV is 38mm, the well inclination accuracy is ±0.15 degrees, the azimuth accuracy is ±1.5 degrees, and the operating temperature range is -25℃ to 125℃.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This invention significantly improves the efficiency and accuracy of casing window opening and accompanying wellbore directional drilling by optimizing the parameters. The high hardness of the composite milling cone ensures the regularity and durability of the window. The combined use of the low-angle screw motor and the roller cone drill makes the directional drilling process more stable and precise. This solution not only reduces drilling costs but also effectively reduces construction risks, providing a solid foundation for subsequent sidetracking operations.

[0027] 2. This invention, through the combination of magnetic ranging and intelligent control, achieves precise distance control between the accompanying wellbore and the original well casing, significantly improving the accuracy and efficiency of sidetracking. The real-time monitoring and dynamic adjustment functions of the intelligent control system effectively reduce construction errors and risks, ensuring the smooth progress of the drilling process. The design of this embodiment provides higher reliability and accuracy for sidetracking operations under complex well conditions, further optimizing the construction process.

[0028] 3. This invention, through the combination of external pipe opening and cement sealing, achieves complete sealing of abandoned wells and efficient establishment of new channels. The efficient milling function of the turbine-type external pipe opening tool and the reliable sealing function of the cement sealing pipe string significantly improve the safety and reliability of construction. This design ensures the complete sealing of abandoned wells and provides a stable foundation for the establishment of new channels, effectively reducing environmental pollution and construction risks.

[0029] 4. By setting up intelligent optimization and full-process control, this invention can improve the automation level and construction efficiency of side-drilling technology. Furthermore, by setting up real-time monitoring and dynamic adjustment functions of the intelligent control system, it can not only improve the accuracy and efficiency of construction, but also effectively reduce construction costs and risks, ensure the smooth progress of the construction process and the reliability of the final result. Finally, through intelligent optimization and full-process control, it can provide an efficient and safe construction method for the reconstruction of abandoned wells without access. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the overall structure of the sleeve opening tube column of the present invention;

[0032] Figure 3 This is a schematic diagram of the overall structure of the inclined tubing string accompanying side-drilling according to the present invention;

[0033] Figure 4 This is a schematic diagram of the overall structure of the magnetic ranging-side drilling accompanying wellbore string of the present invention;

[0034] Figure 5 This is a schematic diagram of the overall structure of the sleeve external window tube column of the present invention;

[0035] Figure 6 This is a schematic diagram of the overall structure of the cement-sealing pipe column of the present invention;

[0036] Figure 7 This is a schematic diagram of the overall framework of the flowchart of the present invention;

[0037] Figure 8 This is a schematic diagram of the overall framework from another perspective of the flowchart of the present invention.

[0038] In the diagram: 1. Tubing string 1; 2. Drill pipe; 3. Drilling gyroscope measuring instrument 1; 4. Feed rod; 5. Directional guide; 6. Casing window string; 61. Weight rod; 62. Low-speed screw motor; 63. Compound milling cone; 7. Sidetracking accompanying borehole skewed tubing string; 71. Drilling gyroscope measuring instrument 2; 72. Low-angle screw motor 1; 73. Roller cone drill 1; 8. Magnetic ranging - sidetracking accompanying borehole tubing 1; 81. Magnetic steering ranging. Instruments; 82. Drilling while measuring gyroscope instrument three; 83. Low-bend screw motor two; 84. Roller cone drill two; 9. Magnetic ranging-side drilling accompanying wellbore tubing two; 91. Drilling while measuring gyroscope instrument four; 92. Turbine type external window opening tool; 93. Milling drill bit; 10. Cement plugging tubing string; 101. Tubing; 102. Packer; 103. Check valve; 104. Guide directional device; 105. Cement injection tubing string; 106. Cement. Detailed Implementation

[0039] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0040] Example 1: The core function of this example is to achieve sidetracking through casing windowing and accompanying wellbore directional drilling. For details, please refer to [link to example]. Figure 1 and Figure 2As shown, a sidetracking device for rebuilding a channel in an abandoned well without access includes a tubing string 1, a drill pipe 2 inside the tubing string 1, a gyroscope 3 fixedly connected to the bottom of the drill pipe 2, a feed rod 4 fixedly connected to the bottom of the gyroscope 3, a directional device 5 fixedly connected to the bottom of the inner cavity of the tubing string 1, an installation kit at the connection between the drill pipe 2 and the gyroscope 3, and a casing adapted to the bottom of the installation kit at the lower part of the drill pipe 2. 6. Window-opening tubing string, 7. Side-drilling accompanying borehole deflection tubing string, 8. Magnetic ranging-side-drilling accompanying borehole tubing string one, 9. A cement-sealed tubing string 10 is installed at the lower part of the magnetic ranging-side-drilling accompanying borehole tubing string two. The casing window-opening tubing string 6 includes a weight rod 61, with a low-speed screw motor 62 fixedly connected to the bottom of the weight rod 61. A composite milling cone 63 is fixedly connected to the bottom of the low-speed screw motor 62, and the composite milling cone 63 includes a window-opening milling cone and a window-repairing milling cone. Used for milling the inner wall of the casing to form and trim windows, the composite milling cone 63 is made of diamond composite teeth with a hardness of 85-93 HRA. The drilling parameters for window opening are a displacement of 800 LPM, a rotation speed of 100-120 RPM, a working torque of ≤500 ftlbs, and a drilling pressure of 5-20 KN. The side-drilling accompanying wellbore skew string 7 includes a drilling gyroscope measuring instrument 2 71, which has a low-bend screw motor at its bottom. 72. A low-angle screw motor 72 is rotatably connected to a roller drill 73 at its bottom. The low-angle screw motor 72 is used to output rotational power, and the roller drill 73 is used to cut the formation, drilling with a dogleg angle of <0.5° / m, and making an inclination to a horizontal displacement of 5m. The outer diameter of the low-angle screw motor 72 is 79-146mm, the power is 36-75HP, the torque is 1200-2600NM, and the working displacement is 10-30L / s.

[0041] First, drill pipe 2 with directional tool 5 is moved to the window position. After measuring and adjusting the azimuth, directional tool 5 is mounted. The composite milling cone 63 is made of diamond composite tooth material with a hardness of 85-93HRA, which can efficiently mill the inner wall of the casing to form and repair the window. The window drilling parameters are displacement of 800LPM, rotation speed of 100-120RPM, working torque ≤500ftlbs, and drilling pressure of 5-20KN. Then, drill pipe 2 with bottom directional tool string is drilled with a dogleg angle of less than 0.5° / m, and the directional tool is built up to a horizontal displacement of 5m. The low-bend screw motor 72 has an outer diameter of 79-146mm, a power of 36-75HP, a torque of 1200-2600NM, and a working displacement of 10-30L / s. The roller cone drill 73 is used to cut the formation to ensure the stability and efficiency of the drilling process.

[0042] By optimizing the parameters of casing window opening and accompanying wellbore directional drilling, the window opening efficiency and directional drilling accuracy have been significantly improved. The high hardness of the composite milling cone 63 material ensures the regularity and durability of the window. The combined use of the low-bend screw motor 72 and the roller cone drill 73 makes the directional drilling process more stable and precise. This solution not only reduces drilling costs but also effectively reduces construction risks, providing a solid foundation for subsequent sidetracking operations.

[0043] Example 2 adds magnetic ranging and intelligent control functions to Example 1 to ensure precise distance control between the accompanying wellbore and the original well casing. For further details, please refer to [link to example 1]. Figure 4 As shown, the magnetic ranging-side drilling accompanying wellbore pipe 8 includes a magnetic guide rangefinder 81. A drilling gyroscope measuring instrument 3 82 is fixedly connected to the bottom of the magnetic guide rangefinder 81. A low-bend angle screw motor 2 83 is fixedly connected to the bottom of the drilling gyroscope measuring instrument 3 82. A roller cone drill 2 84 is connected to the output end of the low-bend angle screw motor 2 83. The magnetic guide rangefinder 81 is used to measure the distance and azimuth relationship between the magnetic ranging-side drilling accompanying wellbore pipe 8 and the tubing string 1, guiding the accompanying wellbore to approach the tubing string 1 and maintain a lateral distance of 30cm or less.

[0044] In the specific implementation process, the magnetic steering distance measuring instrument 81 measures the distance and azimuth relationship between the accompanying wellbore and the tubing string 1 in real time, guiding the accompanying wellbore to approach the tubing string 1 and maintain a lateral distance of 30cm or less. The intelligent control system includes a data processing module and a trajectory adjustment module. The data processing module receives real-time data from the magnetic steering distance measuring instrument 81 and the drilling gyroscope measuring instruments 1, 2, 3, and 4 91. The trajectory adjustment module dynamically adjusts the tool face angle and drilling pressure of the low-bend screw motor 1 72 and the low-bend screw motor 2 83 according to the real-time data. The drill pipe 2 has a bottom directional tool string. The magnetic steering distance measuring instrument 81 measures the distance and azimuth, guiding the side-drilling accompanying wellbore inclined tubing string 7 to approach the tubing string 1 and maintain a lateral distance of 30cm or less. The intelligent control system monitors the drilling parameters in real time and automatically adjusts the tool face angle and drilling pressure to ensure the accuracy and stability of the drilling trajectory.

[0045] Furthermore, by combining magnetic ranging and intelligent control, precise distance control between the accompanying wellbore and the original well casing is achieved, significantly improving the accuracy and efficiency of sidetracking. The real-time monitoring and dynamic adjustment functions of the intelligent control system effectively reduce construction errors and risks, ensuring the smooth progress of the drilling process. The design of this embodiment provides higher reliability and accuracy for sidetracking operations under complex well conditions, further optimizing the construction process.

[0046] Example 3, based on Example 2, adds external window opening and cement sealing functions to achieve complete sealing of abandoned wells and establishment of new channels. For further details, please refer to [link to example 2]. Figure 5and Figure 6 As shown, the magnetic ranging-side drilling accompanying wellbore tubing 2 9 includes a drilling gyroscope measuring instrument 4 91, a turbine-type external casing window opening tool 92, and a milling drill bit 93. The bottom of the drilling gyroscope measuring instrument 4 91 is equipped with a turbine-type external casing window opening tool 92, and the bottom of the turbine-type external casing window opening tool 92 is connected to the milling drill bit 93. The turbine-type external casing window opening tool 92 is used to open a window outside the casing, and the milling drill bit 93 is used to grind the casing. The cement sealing tubing string 10 includes tubing 101, a packer 102, and a one-way valve 103. The bottom of the one-way valve 103 is equipped with a guide 104, and the bottom of the one-way valve 103 is connected to a cement injection tubing string 105. The cement injection tubing string 105 is filled with cement 106 and is used to inject cement 106. The packer 102 is used to seal the annulus, and the one-way valve 103 is used to prevent the cement 106 from returning.

[0047] In this embodiment, during implementation, firstly, a turbine-type external window opening tool 92 is used to mill the pipe column 1 to form a window. The turbine-type external window opening tool 92 ensures the regularity and opening efficiency of the window through high-speed rotation and precise control. Subsequently, an oil pipe 101 is inserted into the pipe column 1, and cement 106 is squeezed into the ash injection pipe column 105 to achieve sealing and scrapping. The cement sealing pipe column 10 includes an oil pipe 101, a packer 102, a one-way valve 103, and an ash injection pipe column 105. The ash injection pipe column 105 is filled with cement 106 for squeezing cement to achieve sealing and scrapping. The packer 102 is used to seal the annulus, and the one-way valve 103 is used to prevent the cement 106 from returning, ensuring the integrity and reliability of the sealing process.

[0048] Furthermore, this embodiment combines external pipe opening and cement sealing to achieve complete sealing of abandoned wells and efficient establishment of new channels. The efficient milling function of the turbine-type external pipe opening tool 92 and the reliable sealing function of the cement sealing pipe string 10 significantly improve the safety and reliability of construction. This design ensures the complete sealing of abandoned wells and provides a stable foundation for the establishment of new channels, effectively reducing environmental pollution and construction risks.

[0049] The drill pipe 2 is 2-7 / 8 inches in size. The outer diameter of the tools for the drilling gyroscope measuring instruments 1-3, 2-71, 3-82 and 4-91 is 38 mm. The well inclination accuracy is ±0.15 degrees, the azimuth accuracy is ±1.5 degrees, and the operating temperature range is -25℃ to 125℃.

[0050] Example 4: The present invention also discloses a side-drilling process for a side-drilling device, comprising the following steps:

[0051] S1: Drill a window on the side of the original casing. Drill rod 2 with directional tool 5 is moved to the window position. After measuring and adjusting the orientation, directional tool 5 is mounted. Drill rod with composite milling cone 63 is used to mill the inner wall of the casing to form a window.

[0052] S2: Accompanying the wellbore build-up, drill pipe 2 with bottom directional tool string drills at a build-up rate of <0.5° / m, and builds up to a horizontal displacement of 5m;

[0053] S3: Use magnetic ranging to guide the side-drilling process accompanying the wellbore. Drill pipe 2 has a bottom orientation tool string. Magnetic guide rangefinder 81 measures the distance and orientation. Guide the side-drilling process to bring the inclined tubing string 7 close to tubing string 1, maintaining a lateral distance of 30cm or less.

[0054] S4: External window opening: Use turbine-type external window opening tool 92 to mill the pipe column 1 to form a window;

[0055] S5: Cement sealing and scrapping. Insert oil pipe 101 into pipe string 1, and squeeze cement 106 into ash injection pipe string 105 to achieve sealing and scrapping.

[0056] This embodiment further optimizes the functions of the intelligent control system based on Embodiment 3 to achieve real-time monitoring and dynamic adjustment throughout the entire process. For details, please refer to [link / reference needed]. Figure 7 and Figure 8 As shown, an intelligent control system is installed between the magnetic ranging-side drilling accompanying wellbore pipe 8 and the drill pipe 2 to adjust the drilling trajectory in real time, ensuring that the lateral distance between the accompanying wellbore and the original well casing is kept within 30cm, while optimizing drilling efficiency and accuracy.

[0057] The intelligent control system includes a data processing module and a trajectory adjustment module. The data processing module receives real-time data from the magnetic guidance rangefinder 81 and the drilling gyroscope measurement instruments 1-3, 2-71, 3-82, and 4-91. The trajectory adjustment module dynamically adjusts the tool face angle and drill pressure of the low-angle screw motor 1-72 and 2-83 based on the real-time data. Step S41 is added after step S4:

[0058] S41: Optimize the external window opening of the pipe. Utilize the intelligent control system to monitor the working status of the turbine-type external window opening tool 92 in real time, and automatically adjust the cutting angle and rotation speed of the milling drill bit 93 to ensure the regularity of the window and the efficiency of the window opening.

[0059] The intelligent control system monitors the torque and drilling pressure of the milling drill bit 93 through sensors, and dynamically adjusts the rotation speed and drilling fluid discharge of the turbine-type external casing opening tool 92 to adapt to casings of different thicknesses.

[0060] In this embodiment, during the specific implementation process, the intelligent control system monitors the working status of the turbine-type external casing opening tool 92 through sensors, automatically adjusts the cutting angle and rotation speed of the milling drill bit 93 to ensure the regularity of the window and the opening efficiency. At the same time, the intelligent control system monitors the torque and drilling pressure of the milling drill bit 93, and dynamically adjusts the rotation speed and drilling fluid discharge of the turbine-type external casing opening tool 92 to adapt to casings of different thicknesses. After the external casing is opened, the intelligent control system continues to monitor the drilling parameters in real time, automatically adjusts the drilling trajectory and drilling pressure, and ensures the accuracy and efficiency of the entire sidetracking process.

[0061] By setting up intelligent optimization and full-process control, the automation level and construction efficiency of the side-drilling process can be improved. Furthermore, by setting up the real-time monitoring and dynamic adjustment functions of the intelligent control system, not only can the accuracy and efficiency of construction be improved, but construction costs and risks can also be effectively reduced, ensuring the smooth progress of the construction process and the reliability of the final result. Finally, through intelligent optimization and full-process control, an efficient and safe construction method can be provided for the reconstruction of abandoned wells without access.

[0062] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A side tracking device for reconstructing a channel for a plugged well, comprising a tubular string (1), characterized in that: The pipe column one (1) is internally provided with a drill rod (2), the bottom of the drill rod (2) is fixedly connected with a while drilling gyro measuring instrument one (3), the bottom of the while drilling gyro measuring instrument one (3) is fixedly connected with a running-in rod (4), the inner cavity bottom of the pipe column one (1) is fixedly connected with a whipstock (5), the drill rod (2) is provided with a mounting kit at the connecting place with the while drilling gyro measuring instrument one (3), the lower part of the drill rod (2) is provided with a casing windowing pipe column (6), a side drilling accompanying wellbore inclined pipe column (7), a magnetic distance measuring-side drilling accompanying wellbore pipe one (8), a magnetic distance measuring-side drilling accompanying wellbore pipe two (9) matched with the bottom of the mounting kit, the lower part of the magnetic distance measuring-side drilling accompanying wellbore pipe two (9) is provided with a cement plugging pipe column (10); The casing windowing pipe column (6) comprises a weighted rod (61), the bottom of the weighted rod (61) is fixedly connected with a low-speed screw rod motor (62), the bottom of the low-speed screw rod motor (62) is fixedly connected with a composite milling cone (63), the composite milling cone (63) comprises a windowing milling cone and a window repairing milling cone, which are used for milling the inner wall of the casing to form a window and repair the window; The magnetic distance measuring-side drilling accompanying wellbore pipe one (8) comprises a magnetic guide distance measuring instrument (81), the bottom of the magnetic guide distance measuring instrument (81) is fixedly connected with a while drilling gyro measuring instrument three (82), the bottom of the while drilling gyro measuring instrument three (82) is fixedly connected with a low-bend-angle screw rod motor two (83), the output end of the low-bend-angle screw rod motor two (83) is connected with a roller bit two (84), the magnetic guide distance measuring instrument (81) is used for measuring the distance and the orientation relationship between the magnetic distance measuring-side drilling accompanying wellbore pipe one (8) and the pipe column one (1), guiding the accompanying wellbore to approach the pipe column one (1) and keeping the horizontal distance within 30cm. The magnetic distance measuring-side drilling accompanying wellbore pipe two (9) comprises a while drilling gyro measuring instrument four (91), a turbine type pipe outer windowing tool (92) and a milling bit (93), the bottom of the while drilling gyro measuring instrument four (91) is provided with the turbine type pipe outer windowing tool (92), the bottom of the turbine type pipe outer windowing tool (92) is connected with the milling bit (93), the turbine type pipe outer windowing tool (92) is used for opening a window outside the casing, and the milling bit (93) is used for grinding the casing.

2. A side tracking device for reconstructing a companion passage of a dead well without passage according to claim 1, characterized in that: The side drilling accompanying wellbore inclined pipe column (7) comprises a while drilling gyro measuring instrument two (71), the bottom of the while drilling gyro measuring instrument two (71) is provided with a low-bend-angle screw rod motor one (72), the bottom of the low-bend-angle screw rod motor one (72) is rotatably connected with a roller bit one (73), the low-bend-angle screw rod motor one (72) is used for outputting rotary power, and the roller bit one (73) is used for cutting the stratum to drill at a dogleg of <0.5° / m and to deflect to a horizontal displacement of 5m. The outer diameter of the low-bend-angle screw rod motor one (72) is 79-146mm, the power is 36-75HP, the torque is 1200-2600NM, and the working displacement is 10-30L / s.

3. A side tracking device for reconstructing a companion passage of a dead well without passage according to claim 1, characterized in that: The cement plugging string (10) is provided with a tubing (101), a packer (102), and a one-way valve (103), the bottom of the one-way valve (103) is provided with a whipstock (104), the bottom of the one-way valve (103) is connected with a cementing string (105), the cementing string (105) is filled with cement (106), the cementing string (105) is used for cementing (106), the packer (102) is used for annulus sealing, and the one-way valve (103) is used for preventing the cement (106) from returning upward; The tool outer diameters of the first, second, third and fourth gyroscopic surveying tools (3, 71, 82 and 91) are 38 mm, the well inclination accuracy is ±0.15 degrees, the azimuth accuracy is ±1.5 degrees, and the working temperature range is -25-125℃.

4. A sidetracking process for reconstructing a companion passage for a channelless abandoned well, characterized by, The sidetracking device of any one of claims 1-3, comprising the following steps: S1, original casing sidetracking windowing: the drill pipe (2) is taken to the windowing position with a whipstock (5), the whipstock (5) is hung after the azimuth is measured and adjusted, the drill pipe is taken to mill the casing inner wall with a composite milling cone (63), and a window is formed; S2, accompanying borehole build-up: the drill pipe (2) is taken to drill with a bottom directional tool string at a build-up rate of <0.5° / m, and the build-up is taken to a horizontal displacement of 5 m; S3, using magnetic distance measurement to guide the sidetracking accompanying borehole: the drill pipe (2) is taken to the bottom with a mounting kit, the magnetic distance measurement instrument (81) measures the distance and azimuth to guide the sidetracking accompanying borehole whipstock (7) to approach the pipe string one (1) and keep the lateral distance within 30 cm; S4, pipe outer windowing: the pipe string one (1) is milled with a turbine pipe outer windowing tool (92) to form a window; S5, cement plugging abandonment: the tubing (101) is lowered into the pipe string one (1), and the cement (106) is squeezed into the cementing string (105) to achieve plugging abandonment.

5. The sidetracking process of claim 4, wherein, In step S1, the material of the composite milling cone (63) is diamond composite teeth, the hardness is 85-93HRA, the windowing drilling parameters are 800 LPM of displacement, 100-120 RPM of rotation speed, ≤500 ftlbs of working torque, and 5-20 KN of drilling pressure, and the specification of the drill pipe (2) is 2-7 / 8 inches.

6. The sidetracking process of claim 4, wherein, In step S3, the magnetic distance measurement instrument (81) is used to measure the distance and azimuth relationship between the magnetic distance measurement-sidetracking accompanying borehole pipe one (8) and the pipe string one (1) to guide the accompanying borehole to approach the pipe string one (1) and keep the lateral distance within 30 cm.

7. The sidetracking process of claim 4, wherein, Further comprising step S41 after step S4: S41: optimizing pipe outer windowing: the working state of the turbine pipe outer windowing tool (92) is monitored in real time by an intelligent control system, the cutting angle and rotation speed of the milling bit (93) are automatically adjusted to ensure the regularity and windowing efficiency of the window; The intelligent control system monitors the torque and drilling pressure of the milling bit (93) through a sensor, dynamically adjusts the rotation speed and drilling fluid displacement of the turbine pipe outer windowing tool (92), and adapts to different thicknesses of the casing.

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