Full-radial drilling and grinding system and drilling and grinding method for oil and gas well

Abstract

The invention provides a full-radial drilling and grinding system and a drilling and grinding method for an oil and gas well. The drilling and grinding system comprises a grinding shoe device, a drill collar pipe column, a hydraulic core shift variable-diameter stabilizer, a drill rod pipe column, a derrick, traction lifting equipment, rotary power equipment and drilling and grinding liquid circulating equipment. The rotary power equipment drives the drill rod pipe column to rotate around the axis of the drill rod pipe column, and the milling shoe device makes circular motion around the axis of a shaft close to the shaft wall under the action of the core-shifting thrust of the hydraulic core-shifting variable-diameter stabilizer, so that the turning radius of the milling shoe device is increased, and the milling range of the milling shoe device is enlarged; and meanwhile, the milling teeth at the end part of the milling shoe shell rotate around the mandrel to generate a secondary cutting effect, so that full-radial drilling and grinding in a shaft are realized. The problems that in existing oil and gas well drilling and grinding, edge skin is left between a grinding and milling tool and a well wall gap, the phenomena of bouncing and clamping of the drilling and grinding tool occur, and when fishes are drilled and ground in an open hole section, an original well hole is laterally drilled, a second channel is formed, and downhole accidents are complicated are solved.

Description

Technical Field

[0001] The invention relates to the field of oil well repair, and in particular to a full radial drilling and grinding system and a drilling and grinding method for oil and gas wells. Background Art

[0002] During the production process of oil and gas wells in the petroleum industry, various factors such as formation sanding, scaling, corrosion, casing deformation, and logging tool drop may cause complicated situations such as buried production layers in the well, blockage, sticking, breaking, and perforation of the production string, resulting in the need for inspection and maintenance of the production wells. Various well repair technology and tools are often used during the operation.

[0003] Drilling and milling technology is a commonly used treatment method for well repair operations. The current drilling and milling methods often leave edges between the milling tool and the well wall after milling, resulting in jamming and sticking of the drilling and milling tool. In severe cases, the tool may be stuck and cause a secondary downhole accident. Drilling and milling in the open hole section may also cause side drilling out of the original wellbore, forming a second channel, which complicates downhole accidents. Summary of the invention

[0004] The main purpose of the present invention is to provide a full radial drilling and grinding system and method for oil and gas wells, so as to at least solve the problems that the existing oil and gas well drilling and grinding will leave a skin between the grinding tool and the well wall, causing the drilling and grinding tool to get stuck and jammed. In severe cases, there is a risk of the tool being stuck and causing a secondary downhole accident, as well as drilling and grinding fish in the open hole section, and side drilling out of the original wellbore to form a second channel, which complicates the downhole accident.

[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, a full radial drilling and grinding system for oil and gas wells is provided, comprising: a grinding shoe device, the grinding shoe device is located at the drilling and grinding working surface in the wellbore; a drill collar string, the lower end of which is connected to the grinding shoe device; a hydraulic eccentric reducer stabilizer, the lower end of which is connected to the upper end of the drill collar string, and the hydraulic eccentric reducer stabilizer is used to make the grinding shoe device close to the inner wall of the wellbore; a drill pipe string, the lower end of which is connected to the hydraulic eccentric reducer stabilizer, and the upper end of which extends upward to the outside of the wellbore; the grinding shoe device, the drill collar string, and the hydraulic eccentric reducer stabilizer are connected to the inner wall of the wellbore. The fixer and the drill pipe string form a drilling and grinding pipe string; a derrick is arranged just above the wellbore; a traction and lifting device is arranged on the derrick and connected to the drill pipe string, and the traction and lifting device is used to lift or lower the drilling and grinding pipe string along the height direction of the wellbore; a rotating power device is arranged on the traction and lifting device, and the rotating power device is used to drive the drilling and grinding pipe string to rotate so that the grinding shoe device rotates around the circumference of the wellbore; a drilling and grinding fluid circulation device is arranged on the ground at the upper end of the wellbore, and the drilling and grinding fluid circulation device is connected to the drill pipe string, and the drilling and grinding fluid circulation device is used to circulate and pump the drilling and grinding fluid to the drilling and grinding pipe string through the drill pipe string and receive the drilling and grinding fluid returned in the wellbore.

[0006] Furthermore, the grinding shoe device includes: a grinding shoe shell, the lower end surface of the grinding shoe shell is provided with milling teeth, and the milling teeth are in contact with the drilling and grinding working surface; a cylindrical accommodating cavity extending along its axial direction is opened inside the grinding shoe shell; a core shaft, the lower half of the core shaft is rotatably installed in the cylindrical accommodating cavity around the axial direction of the cylindrical accommodating cavity, and the upper half of the core shaft extends to the outside of the cylindrical accommodating cavity along the axial direction of the cylindrical accommodating cavity; a core shaft pressing sleeve, which is sleeved on the upper half of the core shaft and fixedly connected to the upper port of the cylindrical accommodating cavity, and the core shaft pressing sleeve and the core shaft can rotate relative to each other; an upper joint, which is fixedly installed on the upper end of the core shaft and is connected to the core shaft pressing sleeve so that it can rotate relative to each other; wherein the upper joint is fixedly connected to the lower end of the drill collar pipe column through a thread.

[0007] Further, the hydraulic eccentric variable diameter stabilizer comprises: a body, the lower end of the body is connected to the upper end of the drill pipe string by a thread, and the upper end of the body is connected to the lower end of the drill pipe string by a thread; a fluid channel and a side channel perpendicular to the fluid channel are arranged inside the body along its length direction, and the fluid channel connects the drill pipe string and the drill pipe string to each other; a piston column is movably arranged in the side channel along the axial direction of the side channel, and one end of the piston column extends to the outside of the side channel; a support arm mechanism, the first end of the support arm mechanism is hinged to the side wall of the body, and the second end of the support arm mechanism is a free end; a reset mechanism is arranged on the side wall of the body and corresponds to the first end of the support arm mechanism; wherein the support arm mechanism is parallel to the outer side wall of the body in the initial state; the piston column is used to move outward along the axial direction of the side channel under the action of the fluid pressure inside the fluid channel to lift the support arm mechanism so that the second end of the support arm mechanism abuts against the well wall; the reset mechanism is used to act on the support arm mechanism when the fluid pressure inside the fluid channel stops so that the support arm mechanism returns to the initial state.

[0008] Furthermore, the traction and lifting equipment includes: a square drill rod, the lower end of which is connected to the upper end of the drill rod column; a crane, the upper end of which is suspended and connected to the top of the derrick; the lower end of the crane is suspended and connected to the upper end of the square drill rod; wherein the crane lifts or lowers the drill pipe string through the square drill rod.

[0009] Furthermore, the crane includes: a crown block, which is arranged at the top of the derrick; a traveling pulley, which is connected to the crown block through a steel cable; a large hook, which is arranged at the lower end of the traveling pulley and is suspended and connected to the upper end of the square drill rod; a winch, which is arranged on the ground and is connected to the crown block and the traveling pulley through a steel cable to drive the traveling pulley to move up and down to lift or lower the drill pipe string through the square drill rod.

[0010] Furthermore, the rotary power device comprises: a turntable, which is arranged on the ground and connected to the kelly, and the turntable is used to drive the kelly to rotate so as to drive the drill and mill pipe string to rotate.

[0011] Furthermore, the drilling and grinding fluid circulation equipment comprises: a mud pool, which is arranged on the ground and filled with drilling and grinding fluid; a mud pump, which is arranged on the ground and the suction port of the mud pump is connected to the mud pool through a pipeline; a faucet, which is arranged at the top of the square drill rod and communicated with the inner cavity of the square drill rod, and the output port of the mud pump is connected to the faucet through a pipeline to transport the drilling and grinding fluid to the drilling and grinding pipe string through the faucet and the square drill rod; a vibrating screen, one end of the vibrating screen is connected to the upper port of the wellbore through a connecting pipe, and the other end of the vibrating screen (84) is connected to the mud tank through the connecting pipe, and the vibrating screen is used to vibrate and filter the drilling and grinding fluid returned from the wellbore and then guide it into the mud tank.

[0012] According to a second aspect of the present invention, a full radial drilling and grinding method for oil and gas wells is provided. The drilling and grinding method is applied to the drilling and grinding system of the above content. The drilling and grinding method comprises the following steps: connecting the grinding shoe device, the drill collar pipe string, the hydraulic eccentric variable diameter stabilizer and the drill pipe string in sequence from bottom to top to form a drilling and grinding pipe string, and then installing it at the bottom of the traction and lifting device; lowering the drilling and grinding pipe string to a preset position in the wellbore by the traction and lifting device; pumping drilling and grinding fluid into the drilling and grinding pipe string by the drilling and grinding fluid circulation device so that the hydraulic eccentric variable diameter stabilizer is supported under the action of the fluid pressure. Open to push the hydraulic eccentric reducer stabilizer, drill collar string and grinding shoe device away from the axis of the wellbore and make the grinding shoe device close to the inner wall of the wellbore; drive the drill pipe string to rotate around its axis through the rotary power equipment, and the drill pipe string drives the hydraulic eccentric reducer stabilizer, drill collar string and grinding shoe device to rotate around the axis of the wellbore, so that the grinding shoe device grinds the drilling and grinding working surface in the wellbore; after the grinding and milling is completed, the drilling and grinding fluid circulation equipment is closed to restore the hydraulic eccentric reducer stabilizer to its initial state; lift the drilling and grinding pipe string from the wellbore by the traction lifting equipment.

[0013] The full radial drilling and grinding system for oil and gas wells of the technical solution of the present invention comprises a grinding shoe device, a drill collar string, a hydraulic eccentric reducer stabilizer, a drill pipe string, a derrick, a traction and hoisting device, a rotary power device and a drilling and grinding fluid circulation device, wherein the grinding shoe device is located at the drilling and grinding working surface in the wellbore; the lower end of the drill collar string is connected to the grinding shoe device; the lower end of the hydraulic eccentric reducer stabilizer is connected to the upper end of the drill collar string, and the hydraulic eccentric reducer stabilizer is used to make the grinding shoe device close to the inner wall of the wellbore; the lower end of the drill pipe string is connected to the hydraulic eccentric reducer stabilizer, and the upper end of the drill pipe string extends upward to the outside of the wellbore; the grinding shoe device, the drill collar string, the hydraulic The eccentric core reducer stabilizer and the drill pipe string form a drilling and grinding pipe string; the derrick is arranged directly above the wellbore; the traction and lifting equipment is arranged on the derrick and connected to the drill pipe string, and the traction and lifting equipment is used to lift or lower the drilling and grinding pipe string along the height direction of the wellbore; the rotary power device is arranged on the traction and lifting equipment, and the rotary power device is used to drive the drilling and grinding pipe string to rotate so that the grinding shoe device rotates around the circumference of the wellbore; the drilling and grinding fluid circulation device is arranged on the ground at the upper end of the wellbore, and the drilling and grinding fluid circulation device is connected to the drill pipe string, and the drilling and grinding fluid circulation device is used to circulate and pump the drilling and grinding fluid to the drilling and grinding pipe string through the drill pipe string and receive the drilling and grinding fluid returned in the wellbore. The rotary power device drives the drill pipe string to rotate around its own axis. Under the eccentric thrust of the hydraulic eccentric reducer stabilizer, the hydraulic eccentric reducer stabilizer, the drill collar string and the grinding shoe device rotate around the wellbore axis. The grinding shoe device moves in a circular motion around the wellbore axis close to the wellbore wall, thereby increasing the rotation radius of the grinding shoe device and expanding the grinding range of the grinding shoe device. At the same time, the milling teeth at the end of the grinding shoe housing rotate around the mandrel to produce a secondary cutting effect, realizing full radial drilling and grinding in the wellbore. The existing oil and gas well drilling and grinding will leave a skin between the grinding tool and the wellbore wall, causing the drilling and grinding tool to jam and get stuck. In severe cases, the tool may get stuck and cause a secondary downhole accident, and the drilling and grinding will fall in the open hole section. There will also be side drilling out of the original wellbore to form a second channel, which will complicate downhole accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0015] Figure 1 is a structural schematic diagram of an oil and gas well full radial drilling and grinding system that can be selected according to an embodiment of the present invention;

[0016] Figure 2 It is a schematic structural diagram of the downhole portion of a fully radial drilling and grinding system for oil and gas wells that can be selected according to an embodiment of the present invention;

[0017] Figure 3 It is a schematic diagram of the longitudinal section structure of a grinding shoe device of a full radial drilling and grinding system for oil and gas wells which can be selected according to an embodiment of the present invention;

[0018] Figure 4 It is a schematic cross-sectional structure diagram of a grinding shoe device of a full radial drilling and grinding system for oil and gas wells which can be selected according to an embodiment of the present invention;

[0019] Figure 5 It is a schematic structural diagram of a mill housing of a mill device of a full radial drilling and grinding system for oil and gas wells which can be selected according to an embodiment of the present invention;

[0020] Figure 6 It is a structural schematic diagram of a hydraulic eccentric variable diameter stabilizer of a full radial drilling and grinding system for oil and gas wells which can be selected according to an embodiment of the present invention;

[0021] Figure 7 It is a schematic structural diagram of a piston column of a hydraulic eccentric variable diameter stabilizer of a full radial drilling and grinding system for oil and gas wells which can be selected according to an embodiment of the present invention;

[0022] Figure 8 It is a flow chart of an optional full radial drilling and grinding method for oil and gas wells according to an embodiment of the present invention.

[0023] The above drawings include the following reference numerals:

[0024] 10. Shoe grinding device; 11. Shoe grinding shell; 111. First guide hole; 112. Guide water trough; 113. Radial section; 114. Axial section; 12. Milling teeth; 13. Mandrel; 131. Second guide hole; 14. Mandrel sleeve; 15. Upper joint; 151. Cone-shaped connecting hole; 16. First bearing assembly; 161. First axial deep groove ball bearing; 162. First plane needle bearing; 17. Second bearing assembly; 171. Second axial deep groove ball bearing; 172. Second plane needle bearing; 18. Third bearing assembly; 181. Third plane needle bearing; 20. Drill collar column; 30. Hydraulic eccentric reducer stabilizer; 31. Body; 311. Fluid channel; 3111. Axial section; 3112. Oblique section; 312. Side branch channel; 313 , nozzle; 314, sealing gasket; 315, nozzle pressure cap; 32, piston column; 321, first column section; 322, second column section; 323, limit ring; 324, sealing ring; 33, support arm mechanism; 331, support arm; 332, ball seat; 333, ball; 34, reset mechanism; 341, spring sheet; 342, fastening screw; 40, drill pipe column; 50, derrick; 60, traction and lifting equipment; 61, square drill pipe; 62, crane; 621, overhead crane; 622, traveling pulley; 623, large hook; 624, winch; 625, first power machine; 70, rotating power equipment; 71, turntable; 72, second power machine; 80, drilling and grinding fluid circulation equipment; 81, mud tank; 82, mud pump; 83, faucet; 84, vibrating screen. DETAILED DESCRIPTION

[0025] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] The full radial drilling and grinding system for oil and gas wells according to the embodiment of the present invention is as follows: Figure 1 and Figure 2 As shown, it includes a grinding shoe device 10, a drill collar string 20, a hydraulic eccentric reducer stabilizer 30, a drill pipe string 40, a derrick 50, a traction and hoisting device 60, a rotary power device 70 and a drilling and grinding fluid circulation device 80. The grinding shoe device 10 is located at the drilling and grinding working surface in the wellbore; the lower end of the drill collar string 20 is connected to the grinding shoe device 10; the lower end of the hydraulic eccentric reducer stabilizer 30 is connected to the upper end of the drill collar string 20, and the hydraulic eccentric reducer stabilizer 30 is used to make the grinding shoe device 10 close to the inner wall of the wellbore; the lower end of the drill pipe string 40 is connected to the hydraulic eccentric reducer stabilizer 30, and the upper end of the drill pipe string 40 extends upward to the outside of the wellbore; the grinding shoe device 10, the drill collar string 20, the hydraulic eccentric reducer stabilizer 30, and the upper end of the drill pipe string 40 extend upward to the outside of the wellbore. The diameter stabilizer 30 and the drill pipe string 40 form a drilling and grinding pipe string; the derrick 50 is arranged directly above the wellbore; the traction and lifting equipment 60 is arranged on the derrick 50 and connected to the drill pipe string 40, and the traction and lifting equipment 60 is used to lift or lower the drilling and grinding pipe string along the height direction of the wellbore; the rotating power device 70 is arranged on the traction and lifting equipment 60, and the rotating power device 70 is used to drive the drilling and grinding pipe string to rotate so that the grinding shoe device 10 rotates around the circumference of the wellbore; the drilling and grinding fluid circulation equipment 80 is arranged on the ground at the upper end of the wellbore, and the drilling and grinding fluid circulation equipment 80 is connected to the drill pipe string 40, and the drilling and grinding fluid circulation equipment 80 is used to circulate the drilling and grinding fluid to the drilling and grinding pipe string through the drill pipe string 40 and receive the drilling and grinding fluid returned in the wellbore. The rotary power device 70 drives the drill pipe column 40 to rotate around its own axis. Under the eccentric thrust of the hydraulic eccentric reducer stabilizer 30, the hydraulic eccentric reducer stabilizer 30, the drill collar column 20 and the grinding shoe device 10 rotate around the wellbore axis. The grinding shoe device 10 moves in a circular motion around the wellbore axis close to the wellbore wall, thereby increasing the rotation radius of the grinding shoe device 10 and expanding the milling range of the grinding shoe device 10. At the same time, the milling teeth at the lower end of the grinding shoe device 10 rotate around the core shaft to produce a secondary cutting effect, realizing full radial drilling and grinding in the wellbore. The existing oil and gas well drilling and grinding will leave a skin between the milling tool and the wellbore wall, causing the drilling and grinding tool to jam and get stuck. In severe cases, the tool may get stuck and cause a secondary downhole accident, and the drilling and grinding will fall in the open hole section. There will also be side drilling out of the original wellbore to form a second channel, which will complicate downhole accidents.

[0027] In specific implementation, the drill pipe column 40 and the drill collar column 20 are both hollow tubular structures. The lower end of the drill collar column 20 and the upper end of the grinding shoe device 10 are connected by a matching threaded structure; the upper end of the drill collar column 20 and the lower end of the hydraulic eccentric variable diameter stabilizer 30 are connected by a matching threaded structure; the lower end of the drill pipe column 40 and the upper end of the hydraulic eccentric variable diameter stabilizer 30 are connected by a matching threaded structure.

[0028] like Figures 3 to 5 As shown, the grinding shoe device 10 includes a grinding shoe housing 11, a core shaft 13, a core shaft pressing sleeve 14 and an upper joint 15. The lower end surface of the grinding shoe housing 11 is provided with a milling tooth 12, and the milling tooth 12 is in contact with the drilling and grinding working surface; a cylindrical accommodating cavity extending along its axial direction is provided inside the grinding shoe housing 11; the lower half of the core shaft 13 is rotatably installed in the cylindrical accommodating cavity around the axial direction of the cylindrical accommodating cavity, and the upper half of the core shaft 13 extends to the outside of the cylindrical accommodating cavity along the axial direction of the cylindrical accommodating cavity; the core shaft pressing sleeve 14 is sleeved on the upper half of the core shaft 13 and fixedly connected to the upper end of the cylindrical accommodating cavity, and the core shaft pressing sleeve 14 and the core shaft 13 can rotate relative to each other; the upper joint 15 is fixedly installed on the upper end of the core shaft 13 and is rotatably connected to the core shaft pressing sleeve 14; the upper joint 15 is fixedly connected to the lower end of the drill collar pipe column 20 through a thread. The drill pipe column 40 drives the upper joint 15 to rotate through the hydraulic eccentric reducer stabilizer 30 and the drill collar column 20, and the upper joint 15 drives the core shaft 13 to idle, and the grinding shoe shell 11 is in an inoperative state; when the grinding shoe device 10 rotates around the wellbore axis under the action of the hydraulic eccentric reducer stabilizer 30, it drives the grinding shoe device 10 to make a circular motion around the wellbore axis, and the milling teeth 12 at the end of the grinding shoe shell 11 synchronously make a circular motion around the wellbore axis to produce a cutting effect, and the side wall of the grinding shoe shell 11 is close to the inner wall of the wellbore and rotates around the core shaft 13 under the friction force of the inner wall of the wellbore. While reducing the torque increased by the eccentric rotation of the grinding shoe device 10, the milling teeth 12 at the end of the grinding shoe shell 11 rotate around the core shaft 13 to produce a secondary cutting effect, thereby reducing the friction between the grinding shoe shell 11 and the inner wall of the wellbore, and improving the efficiency of the full radial drilling and grinding shoe.

[0029] In a specific implementation, the lower end of the grinding shoe housing 11 is provided with a first guide hole 111 and a plurality of guide water grooves 112 distributed around the first guide hole 111 and interconnected with the first guide hole 111; the core shaft 13 is provided with a second guide hole 131, and the lower end of the second guide hole 131 is connected to and communicated with the first guide hole 111; the upper joint 15 is provided with a frustum-shaped connecting hole 151 recessed toward the inner side thereof, and the frustum-shaped connecting hole 151 is communicated with the upper end of the second guide hole 131; wherein, the frustum The cone-shaped connecting hole 151 is an internal screw hole structure, and the drill bit is fixedly connected to the upper joint 15 through the cone-shaped connecting hole 151 and communicated with the second guide hole 131, so that the fluid pumped from the ground is guided to the milling tooth 12 at the lower end and the side wall of the grinding shoe housing 11 through the second guide hole 131, the first guide hole 111 and the multiple guide grooves 112 in sequence, and returned to the ground through the annular space between the drill bit and the wellbore, so as to cool the milling tooth 12 during the grinding process and carry the drill cuttings generated during the grinding process of the milling tooth 12.

[0030] Furthermore, the first guide hole 111 extends along the central axis of the grinding shoe housing 11, and the second guide hole 131 extends along the central axis of the core shaft 13, so as to ensure the balance of the overall layout. Figure 3 As shown, there are three diversion grooves 112, and the three diversion grooves 112 are evenly spaced along the circumference of the mill shoe housing 11; the diversion grooves 112 include radial sections 113 and axial sections 114, the radial sections 113 extend radially along the mill shoe housing 11, and the axial sections 114 are opened along the outer side wall of the mill shoe housing 11 and are parallel to the central axis of the mill shoe housing 11; the first end of the radial section 113 is connected to the first diversion hole 111, the second end of the radial section 113 is connected to the first end of the axial section 114, and the second end of the axial section 114 extends upward to a preset position along the outer side wall of the mill shoe housing 11. The distributed arrangement of the diversion grooves 112 can evenly and quickly guide the pumped fluid to the milling working surface and the contact surface between the mill shoe housing 11 and the well wall, thereby improving the cooling efficiency.

[0031] Furthermore, the diameter of the lower half of the mandrel 13 is larger than the diameter of the upper half so as to form an annular step structure at the transitional position between the lower half and the upper half of the mandrel 13. Meanwhile, the lower end of the mandrel 13 is also provided with an annular step structure. The eccentric core cutting rotary grinding shoe tool further comprises a first bearing assembly 16, a second bearing assembly 17 and a third bearing assembly 18. The first bearing assembly 16 is arranged at the annular step structure at the lower end of the mandrel 13; the second bearing assembly 17 is arranged at the annular step structure at the transitional position between the lower half and the upper half of the mandrel 13; and the third bearing assembly 18 is arranged between the lower end surface of the upper joint 15 and the upper end surface of the mandrel pressing sleeve 14. By providing the first bearing assembly 16, the second bearing assembly 17 and the third bearing assembly 18, the rotating body composed of the grinding shoe housing 11 and the mandrel pressing sleeve 14 can rotate freely, stably and smoothly relative to the rotating body composed of the mandrel 13 and the upper joint 15, so as to ensure that the grinding shoe housing 11 can smoothly and reliably rotate and produce a secondary cutting effect when rolling friction with the well wall occurs.

[0032] Furthermore, the first bearing assembly 16 includes a first axial deep groove ball bearing 161 and a first plane needle roller bearing 162, the inner ring and the outer ring of the first axial deep groove ball bearing 161 are respectively fixedly connected to the outer side wall of the annular step structure at the lower end of the core shaft 13 and the inner side wall of the bottom end of the cylindrical accommodating cavity, and the first plane needle roller bearing 162 is arranged between the first axial deep groove ball bearing 161 and the lower end surface of the cylindrical accommodating cavity; the second bearing assembly 17 includes a second axial deep groove ball bearing 171 and a second plane needle roller bearing 172, the inner ring and the outer ring of the second axial deep groove ball bearing 171 are respectively fixedly connected to the outer side wall of the upper half of the core shaft 13 and the inner side wall of the cylindrical accommodating cavity, and the second plane needle roller bearing 172 is arranged between the second axial deep groove ball bearing 171 and the lower end surface of the core shaft pressing sleeve 14; the third bearing assembly 18 includes a third plane needle roller bearing 181, and the third plane needle roller bearing 181 is arranged between the lower end surface of the upper joint 15 and the upper end surface of the core shaft pressing sleeve 14. The first axial deep groove ball bearing 161 and the second axial deep groove ball bearing 171 play a role in providing stable lubrication support for circumferential rotation, while the first plane needle roller bearing 162 and the second plane needle roller bearing 172 play a role in providing axial limitation and stable lubrication support; the third plane needle roller bearing 181 plays a role in providing axial stable lubrication support for the upper joint 15 and the core shaft sleeve 14.

[0033] Furthermore, an internal thread structure is provided at the upper end of the cylindrical accommodating cavity, and a matching external thread structure is provided on the outer side wall of the mandrel pressing sleeve 14, and the mandrel pressing sleeve 14 is fixedly connected to the internal thread structure of the cylindrical accommodating cavity through the external thread structure; an external thread structure is provided at the upper end of the mandrel 13, and a matching internal screw hole is provided inside the upper joint 15, and the upper joint 15 is fixedly installed on the upper end of the mandrel 13 through the internal screw hole. The mandrel pressing sleeve 14 is connected to the grinding shoe housing 11 and the upper joint 15 is connected to the mandrel 13 through the thread structure, and the overall connection is stable and convenient for disassembly and assembly.

[0034] Furthermore, if Figure 6 and Figure 7As shown, the hydraulic eccentric variable diameter stabilizer 30 includes a body 31, a piston column 32, a support arm mechanism 33 and a reset mechanism 34. The lower end of the body 31 is fixedly connected to the upper end of the drill collar pipe column 20 through a thread, and the upper end of the body 31 is fixedly connected to the lower end of the drill pipe column 40 through a thread; a fluid channel 311 and a side branch channel 312 vertically connected to the fluid channel 311 are arranged inside the body 31 along its length direction, and the fluid channel 311 connects the drill pipe column 40 with the drill collar pipe column 20, so as to introduce the drilling and grinding fluid from the drilling and grinding fluid circulation device 80 on the ground into the grinding shoe device 10 below; the piston column 32 is movably arranged in the side branch channel 312 along the axial direction of the side branch channel 312, and one side of the piston column 32 The end extends to the outside of the bypass channel 312; the first end of the support arm mechanism 33 is hinged to the side wall of the main body 31, and the second end of the support arm mechanism 33 is a free end; the reset mechanism 34 is arranged on the side wall of the main body 31 and corresponds to the first end of the support arm mechanism 33; wherein, the support arm mechanism 33 is parallel to the outer wall of the main body 31 in the initial state; the piston column 32 is used to move outward along the axial direction of the bypass channel 312 under the action of the internal fluid pressure of the fluid channel 311 to lift the support arm mechanism 33 so that the second end of the support arm mechanism 33 abuts against the well wall; the reset mechanism 34 is used to act on the support arm mechanism 33 when the internal fluid pressure of the fluid channel 311 stops so that the support arm mechanism 33 returns to its initial state. As a result, in the deep structure of oil and gas wells, the upper casing is small and the lower casing is large, which makes it impossible for the internal and external catching tools to enter the fish top smoothly, or during the grinding and milling process, the objects in the well are close to the well wall, and the edge skin is left between the grinding and milling tools and the well wall. When the tool is stuck or stuck, the support arm mechanism 33 is pushed open and abuts against the well wall, thereby pushing the entire drilling tool away from the axis of the wellbore, and then causing the grinding shoe device 10 connected to the lower end of the main body 31 to deviate from the axis of the wellbore and close to the well wall. When the drilling tool moves up and down, the grinding shoe device 10 at the lower end deviates from the center of the wellbore and moves up and down, so as to realize the salvage of eccentric fish top objects in the well; when the drilling tool is rotated and lowered, the grinding shoe device 10 at the lower end is close to the well wall and makes a circular motion around the wellbore, thereby expanding the grinding radius of the grinding tool and realizing the full radial drilling and grinding of the fish top of the objects at the bottom of the well. The invention solves the problems in the prior art that during the well repair and salvage process, the internal and external salvage tools cannot smoothly enter the fish top, thus affecting the salvage effect, and the drilling, grinding, sleeve and milling tools will leave edge skin between the grinding and milling tools and the well wall during the grinding and milling process, which easily causes the tool to get stuck.

[0035] Optionally, a tapered connection hole is provided at the upper end of the body 31, and an internal thread structure is provided on the inner side wall of the connection hole, and the upper end of the body 31 is connected to the lower end of the drill pipe column 40 through the internal thread structure; a tapered connector is provided at the lower end of the body 31, and an external thread structure is provided on the outer side wall of the connector, and the lower end of the body 31 is connected to the drill collar column 20 through the external thread structure. By providing tapered connection holes and connectors at both ends of the body 31, it can be conveniently, quickly and stably sealed and connected with drilling tools, fishing tools or milling tools, ensuring the convenience of operation and stability of use.

[0036] Furthermore, a nozzle 313 is provided at the lower end of the main body 31, and the nozzle 313 is sealed and connected to the lower port of the fluid channel 311 through a sealing gasket 314 and fastened by a nozzle pressure cap 315; the lower end of the fluid channel 311 is sealed and connected to the salvage tool or the grinding and milling tool through the nozzle 313, further ensuring a stable and reliable sealing connection with the salvage tool or the grinding and milling tool.

[0037] Furthermore, the fluid channel 311 includes an axial section 3111 and an oblique section 3112, the axial section 3111 is parallel to the central axis of the body 31 and is spaced a preset distance away from the piston column 32; one end of the axial section 3111 extends to the connecting hole at the upper end of the body 31 and is interconnected with the drilling tool; the oblique section 3112 is inclined at a preset angle to the central axis of the body 31, one end of the oblique section 3112 is connected to the other end of the axial section 3111, and the other end of the oblique section 3112 is connected to the nozzle 313 and is interconnected with the salvage tool or the milling tool through the nozzle 313.

[0038] Furthermore, if Figure 1 and Figure 2As shown, the piston column 32 includes a first column section 321 and a second column section 322, the diameter of the first column section 321 is larger than the diameter of the second column section 322 to form a stepped shaft structure; a limit ring 323 is provided at the outer end of the bypass channel 312; the outer peripheral wall of the first column section 321 is in sliding sealing contact with the inner wall of the bypass channel 312 so as to move along the axial direction of the bypass channel 312 under the pressure of the fluid in the bypass channel 312; optionally, a plurality of sealing rings 324 are sleeved on the first column section 321, and the first column section 321 is connected to the inner wall of the bypass channel 312 through the plurality of sealing rings 324. The wall sliding seal abuts; the inner diameter of the limit ring 323 matches the outer diameter of the second column segment 322, and the second column segment 322 can slide through the inner hole of the limit ring 323. When the first column segment 321 and the second column segment 322 move outward to a certain extent synchronously, the first column segment 321 is stuck by the limit ring 323, thereby limiting the maximum displacement of the piston column 32; the maximum displacement of the piston column 32 determines the maximum expansion angle of the support arm mechanism 33. In actual application, the maximum displacement of the piston column 32 is designed according to the radial size of the wellbore and the maximum expansion angle required for the support arm mechanism 33.

[0039] Furthermore, the support arm mechanism 33 includes a support arm 331, a ball seat 332 and a ball 333. The first end of the support arm 331 is hinged to the side wall of the body 31 through a pin; the ball seat 332 is fixedly arranged at the second end of the support arm 331; a spherical ball groove is opened on the side of the ball seat 332, and the ball 333 can be freely rolled and installed in the ball groove of the ball seat 332 so as to be able to rotate freely; the inner side wall of the support arm 331 close to the first end is opposite to the piston column 32, and the piston column 32 pushes the support arm 331 open when it moves outward, and the ball 333 at the second end of the support arm 331 abuts against the well wall. When the drilling tool moves up and down or rotates and lowers, the ball 333 rolls close to the well wall, thereby effectively reducing the friction resistance of the drilling tool moving up and down or rotating and lowering.

[0040] Furthermore, the reset mechanism 34 includes a spring sheet 341, a first end of the spring sheet 341 is fixedly connected to the side wall of the body 31 by a fastening screw 342, and a second end of the spring sheet 341 is a free end and is pressed on the support arm 331; when the support arm 331 is lifted by the piston column 32, the second end of the spring sheet 341 is driven to flip outward, and the spring sheet 341 undergoes elastic deformation and generates a rotational elastic force. When the fluid pressure inside the fluid channel 311 stops, the piston column 32 retracts, the support arm 331 loses its supporting force, and under the elastic force of the spring sheet 341, the support arm 331 returns to its initial state.

[0041] Furthermore, a receiving groove is provided on the side wall of the main body 31, the depth of the receiving groove matches the radial dimension of the support arm mechanism 33, and the length of the receiving groove matches the length of the support arm mechanism 33; the support arm mechanism 33 is located as a whole in the receiving groove in the initial state; thereby keeping the shape of the entire main body 31 consistent and being able to be conveniently placed in the wellbore.

[0042] Furthermore, if Figure 1 As shown, the traction and hoisting equipment 60 includes a square drill rod 61 and a crane 62. The lower end of the square drill rod 61 is connected to the upper end of the drill rod pipe string 40 by a thread; the upper end of the crane 62 is suspended and connected to the top of the derrick 50; the lower end of the crane 62 is suspended and connected to the upper end of the square drill rod 61; the crane 62 lifts or lowers the drill pipe string through the square drill rod 61. The crane 62 includes a crown block 621, a traveling block 622 and a large hook 623. The crown block 621 is arranged at the top of the derrick 50; the traveling block 622 is connected to the crown block 621 through a steel cable; the large hook 623 is arranged at the lower end of the traveling block 622, and the large hook 623 is suspended and connected to the upper end of the square drill rod 61; the winch 624 is arranged on the ground and is connected to the crown block 621 and the traveling block 622 through a steel cable to drive the traveling block 622 to move up and down to lift or lower the drill pipe string through the square drill rod 61; the winch 624 is connected to the first power machine 625 and is powered by the first power machine 625.

[0043] Furthermore, the rotary power device 70 includes a turntable 71 and a second power machine 72. The turntable 71 is set on the ground and connected to the square drill rod 61. The turntable 71 is used to drive the square drill rod 61 to rotate to drive the drill and mill pipe string to rotate. The turntable 71 is connected to the second power machine 72 and is powered by the second power machine 72.

[0044] Furthermore, the drilling and grinding fluid circulation equipment 80 includes a mud tank 81, a mud pump 82, a faucet 83 and a vibrating screen 84. There are multiple mud tanks 81, and the multiple mud tanks 81 are arranged in parallel on the ground. The mud tanks 81 are filled with drilling and grinding fluid; the mud pump 82 is arranged on the ground, and the suction port of the mud pump 82 is connected to the mud tank 81 through a pipeline; the faucet 83 is arranged at the top of the square drill rod 61 and is connected to the inner cavity of the square drill rod 61, and the output port of the mud pump 82 is connected to the faucet 83 through a pipeline to transport the drilling and grinding fluid to the drilling and grinding pipe string through the faucet 83 and the square drill rod 61; one end of the vibrating screen 84 is connected to the upper port of the wellbore through a pipeline, and the other end of the vibrating screen 84 is connected to the mud tank 81 through a pipeline. The vibrating screen 84 vibrates and filters the drilling and grinding fluid returned from the wellbore and diverts it to the mud tank 81 for storage, thereby circulating the drilling and grinding fluid to the mud pump 82.

[0045] like Figure 1As shown, the drilling tool lifting process is as follows: the control room starts the first power machine 625, and the first power machine 625 provides power to the winch 624 through the transmission mechanism. The control room starts the winch 624 through the control system to retract and release the wire rope. The wire rope drives the traveling pulley 622 to move up and down through the pulley block of the crown block 621. The large hook 623 of the traveling pulley 622 drives the square drill rod 61 and the faucet 83 to move up and down. The lower thread of the square drill rod 61 is connected to the drill pipe string 40, thereby driving the entire drill and grinding pipe string up and down through the drill pipe string 40 to realize the lifting and lowering of the downhole drilling tools.

[0046] The drilling tool rotation working process: the control room starts the second power machine 72, and the second power machine 72 provides power to the turntable 71 through the transmission mechanism. The rotation of the turntable 71 drives the square drill rod 61 to rotate, and the square drill rod 61 drives the entire drilling and grinding pipe string to rotate through the drill pipe string 40 to achieve drilling and grinding of the dropped objects in the well.

[0047] The working process of drilling and grinding fluid circulation: the control room starts the mud pump 82, and the circulating fluid of each mud tank 81 provides drilling and grinding fluid to the inlet end of the mud pump 82 through the connecting pipeline. The outlet end of the mud pump 82 pumps out the drilling and grinding fluid and transports it to the faucet 83 through the connecting pipeline, enters the square drill rod 61 through the faucet 83, and is transported to the drill rod pipe string 40, the hydraulic eccentric reducer stabilizer 30, the drill collar pipe string 20 and the grinding shoe device 10 in sequence through the square drill rod 61, and the drilling and grinding fluid is circulated to the milling teeth 12 at the bottom of the grinding shoe device 10 and the drilling and grinding working surface for cooling and taking away the drill cuttings. Then the drilling and grinding fluid returns from the bottom of the grinding shoe device 10, returns to the ground through the annular gap between the downhole drilling and grinding pipe string and the wellbore, and passes through the overflow pipe, enters the vibrating screen 84 to filter the drill cuttings, and the filtered drilling and grinding fluid flows back to each mud tank 81 through the diversion pipe for storage; the drilling and grinding fluid is circulated from the ground to the wellbore and then back to the ground.

[0048] According to a second embodiment of the present invention, a full radial drilling and grinding method for oil and gas wells is provided. The drilling and grinding method is applied to the drilling and grinding system of the above embodiment, such as Figure 8 As shown, the drilling and grinding method comprises the following steps:

[0049] S102: Connect the grinding shoe device 10, the drill collar column 20, the hydraulic eccentric reducer stabilizer 30 and the drill pipe column 40 from bottom to top in sequence to form a drilling and grinding pipe string and then install it at the bottom of the traction and lifting equipment 60;

[0050] S104: lowering the drilling and grinding pipe string to a preset position in the wellbore by towing and hoisting equipment 60;

[0051] S106: Pump drilling fluid into the drilling and grinding pipe string through the drilling and grinding fluid circulation device 80 to expand the hydraulic eccentric variable diameter stabilizer 30 under the action of fluid pressure to push the hydraulic eccentric variable diameter stabilizer 30, the drill collar pipe string 20 and the grinding shoe device 10 away from the wellbore axis and make the grinding shoe device 10 close to the inner wall of the wellbore;

[0052] S108: driving the drill pipe string 40 to rotate around its axis through the rotary power device 70, and the drill pipe string 40 drives the hydraulic eccentric reducer stabilizer 30, the drill collar string 20 and the grinding shoe device 10 to rotate around the axis of the wellbore, so that the grinding shoe device 10 grinds the drilling and grinding working surface in the wellbore;

[0053] S110: After the milling is completed, the drilling and grinding fluid circulation device 80 is turned off to restore the hydraulic eccentric reducer stabilizer 30 to its initial state; the drilling and grinding pipe string is lifted from the wellbore by the traction hoisting device 60.

[0054] In the full radial drilling and grinding method for oil and gas wells of the present invention, the well repair surface equipment provides the power for stringing down, rotating and circulating the working fluid of the drilling and grinding pipes, the drill pipe string 40 transmits the power, the drill collar string 20 transmits the power, and the grinding shoe device 10 performs drilling pressure. When the hydraulic eccentric variable diameter stabilizer 30 is working, the support arm mechanism 33 expands outward and supports the wellbore wall on one side of the wellbore to provide radial thrust, and the grinding shoe device 10 provides the ability to cut and grind fallen objects. When the drilling and grinding pipe string is lowered to the predetermined working position in the wellbore, the drilling and grinding fluid circulation device 80 pumps in the working fluid with a displacement of 200-450L / min; the fluid flows through the nozzle 313 of the hydraulic eccentric variable diameter stabilizer 30 through the drill pipe column 40. The nozzle 313 has a diameter of 10mm and generates a throttling pressure of 2-5MPa. Under the action of the throttling pressure, the hydraulic eccentric variable diameter stabilizer 30 starts to work, and the support arm mechanism 33 expands outward. After the expansion, the distance e between the end fulcrum of the support arm mechanism 33 and the edge of the hydraulic eccentric variable diameter stabilizer 30 is the eccentric distance, and the support arm The end fulcrum of the mechanism 33 is supported on the wellbore wall on one side, and the radial thrust pushes the tool itself, the drill collar string 20 and the grinding shoe device 10 toward the wellbore wall on the other side of the wellbore. After the working fluid circulates normally, the rotary power equipment 70 drives the drill and grinding pipe string to rotate, the drill pipe string 40 rotates around its own axis, the hydraulic eccentric reducer stabilizer 30, the drill collar string 20 and the grinding shoe device 10 rotate around the wellbore axis, and the grinding shoe device 10 moves in a circular motion around the wellbore axis close to the wellbore wall, thereby increasing the grinding rotation radius, expanding the grinding range, and realizing full radial drilling and grinding in the wellbore.

[0055] The specific process parameters are set as follows:

[0056] D3=D1-8mm, D3 is the outer diameter of the hydraulic eccentric variable diameter stabilizer 30, and D1 is the inner diameter of the oil layer casing.

[0057] D4=D1-6mm, D4 is the outer diameter of the shoe grinding device 10.

[0058] e=D2-D4 / 2-D3 / 2, e is the eccentricity of the hydraulic eccentric reducer stabilizer 30, and D2 is the inner diameter of the technical casing.

[0059] Beneficial effects of the present invention: In the full radial drilling and grinding method for oil and gas wells provided by the present invention, when D1=D2, no edge skin left over from grinding and milling is generated between the grinding shoe device 10 and the wellbore gap; when D2>D1, the grinding radius of the grinding shoe device 10 can be enlarged to achieve full radial drilling and grinding of debris in the wellbore of the D2 inner diameter section; when the wellbore of the D2 inner diameter section is an open hole section, full radial drilling and grinding of the D2 inner diameter open hole section can be achieved without forming a second wellbore sideways to complicate the downhole situation.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A full radial drilling and grinding system for oil and gas wells, characterized in that: include: A grinding shoe device (10), wherein the grinding shoe device (10) is located at a drilling and grinding working surface in the wellbore; A drill collar pipe column (20), the lower end of which is connected to the grinding shoe device (10); A hydraulic eccentric variable diameter stabilizer (30), the lower end of which is connected to the upper end of the drill collar pipe column (20), and the hydraulic eccentric variable diameter stabilizer (30) is used to make the grinding shoe device (10) close to the inner wall of the wellbore; A drill pipe string (40), wherein the lower end of the drill pipe string (40) is connected to the hydraulic eccentric variable diameter stabilizer (30), and the upper end of the drill pipe string (40) extends upward to the outside of the wellbore; the grinding shoe device (10), the drill collar string (20), the hydraulic eccentric variable diameter stabilizer (30) and the drill pipe string (40) form a drilling and grinding pipe string; A derrick (50) is arranged directly above the wellbore; A traction and hoisting device (60) is arranged on the derrick (50) and connected to the drill pipe string (40), and the traction and hoisting device (60) is used to lift or lower the drill pipe string along the height direction of the wellbore; A rotary power device (70) is arranged on the traction and hoisting device (60), and the rotary power device (70) is used to drive the drill and grinder pipe string to rotate so that the grinding shoe device (10) rotates around the circumference of the wellbore; The drilling and grinding fluid circulation device (80) is arranged on the ground at the upper end of the wellbore. The drilling and grinding fluid circulation device (80) is connected to the drill pipe string (40). The drilling and grinding fluid circulation device (80) is used to circulate and pump the drilling and grinding fluid to the drilling and grinding pipe string through the drill pipe string (40) and receive the drilling and grinding fluid returned from the wellbore.

2. The full radial drilling and grinding system for oil and gas wells according to claim 1, characterized in that: The shoe grinding device (10) comprises: A milling shoe housing (11), wherein the lower end surface of the milling shoe housing (11) is provided with milling teeth (12), and the milling teeth (12) are in contact with the drilling and grinding working surface; and a cylindrical accommodating cavity extending along the axial direction thereof is provided inside the milling shoe housing (11); A core shaft (13), wherein the lower half of the core shaft (13) is rotatably mounted in the cylindrical accommodating cavity around the axial direction of the cylindrical accommodating cavity, and the upper half of the core shaft (13) extends to the outside of the cylindrical accommodating cavity along the axial direction of the cylindrical accommodating cavity; A core shaft pressing sleeve (14) is sleeved on the upper half of the core shaft (13) and fixedly connected to the upper end of the cylindrical accommodating cavity, and the core shaft pressing sleeve (14) and the core shaft (13) can rotate relative to each other; An upper joint (15) is fixedly mounted on the upper end of the core shaft (13) and is connected to the core shaft pressing sleeve (14) so ​​as to be relatively rotatable; Wherein, the upper joint (15) is fixedly connected to the lower end of the drill collar pipe column (20) via a thread.

3. The full radial drilling and grinding system for oil and gas wells according to claim 1, characterized in that: The hydraulic eccentric variable diameter stabilizer (30) comprises: A body (31), the lower end of the body (31) is connected to the upper end of the drill collar pipe string (20) through a thread, and the upper end of the body (31) is connected to the lower end of the drill pipe string (40) through a thread; a fluid channel (311) and a side branch channel (312) vertically penetrating the fluid channel (311) are arranged inside the body (31) along its length direction, and the fluid channel (311) connects the drill pipe string (40) and the drill collar pipe string (20) to each other; A piston column (32) is movably disposed in the side branch channel (312) along the axial direction of the side branch channel (312), and one end of the piston column (32) extends to the outside of the side branch channel (312); A support arm mechanism (33), wherein a first end of the support arm mechanism (33) is hingedly connected to a side wall of the body (31), and a second end of the support arm mechanism (33) is a free end; A reset mechanism (34), which is arranged on the side wall of the body (31) and corresponds to the first end of the support arm mechanism (33); Wherein, the support arm mechanism (33) is parallel to the outer wall of the main body (31) in the initial state; the piston column (32) is used to move outward along the axial direction of the branch channel (312) under the action of the internal fluid pressure of the fluid channel (311) to lift the support arm mechanism (33) so that the second end of the support arm mechanism (33) abuts against the well wall; the reset mechanism (34) is used to act on the support arm mechanism (33) when the internal fluid pressure of the fluid channel (311) stops so that the support arm mechanism (33) returns to the initial state.

4. The full radial drilling and grinding system for oil and gas wells according to claim 1, characterized in that: The traction and lifting equipment (60) comprises: A kelly drill rod (61), the lower end of which is connected to the upper end of the drill rod column (40); A crane (62), the upper end of which is suspended and connected to the top of the derrick (50); the lower end of which is suspended and connected to the upper end of the kelly (61); Wherein, the crane (62) lifts or lowers the drill and mill pipe string through the kelly drill rod (61).

5. The full radial drilling and grinding system for oil and gas wells according to claim 4, characterized in that: The crane (62) comprises: A crown block (621) is disposed on the top of the derrick (50); A traveling pulley (622), wherein the traveling pulley (622) is connected to the overhead traveling block (621) via a steel cable; A large hook (623) is arranged at the lower end of the traveling block (622), and the large hook (623) is suspended and connected to the upper end of the kelly rod (61); The winch (624) is arranged on the ground and connected to the crown block (621) and the traveling block (622) through a steel cable to drive the traveling block (622) to move up and down so as to lift or lower the drilling and grinding pipe string through the square drill rod (61).

6. The full radial drilling and grinding system for oil and gas wells according to claim 4, characterized in that: The rotary power device (70) comprises: A rotating disk (71) is arranged on the ground and connected to the kelly rod (61). The rotating disk (71) is used to drive the kelly rod (61) to rotate so as to drive the drill and mill pipe string to rotate.

7. The full radial drilling and grinding system for oil and gas wells according to claim 4, characterized in that: The drilling and grinding fluid circulation device (80) comprises: A mud tank (81) is arranged on the ground, and the mud tank (81) contains drilling fluid; A mud pump (82) is arranged on the ground, and a suction port of the mud pump (82) is connected to the mud tank (81) through a pipeline; A faucet (83) is arranged at the top of the kelly (61) and communicated with the inner cavity of the kelly (61); the output port of the mud pump (82) is connected to the faucet (83) through a pipeline so as to transport drilling and grinding fluid to the drilling and grinding pipe string through the faucet (83) and the kelly (61); A vibrating screen (84), one end of which is connected to the upper port of the wellbore via a connecting pipe, and the other end of which is connected to the mud tank (81) via a connecting pipe. The vibrating screen (84) is used to vibrate and filter the drilling and grinding fluid returned from the wellbore and then guide it into the mud tank (81).

8. A full radial drilling and grinding method for oil and gas wells, characterized in that: The drilling and grinding method is applied to the drilling and grinding system according to any one of claims 1 to 7, and the drilling and grinding method comprises the following steps: The grinding shoe device (10), the drill collar pipe column (20), the hydraulic eccentric reducer stabilizer (30) and the drill pipe column (40) are sequentially connected from bottom to top to form a drilling and grinding pipe string, which is then installed at the bottom of the traction and lifting equipment (60); Lowering the drilling and grinding pipe string to a preset position in the wellbore by means of the traction and lifting equipment (60); Pumping drilling fluid into the drilling and grinding pipe string through a drilling and grinding fluid circulation device (80) so that the hydraulic eccentric reducer stabilizer (30) is expanded under the action of fluid pressure to push the hydraulic eccentric reducer stabilizer (30), the drill collar pipe column (20) and the grinding shoe device (10) away from the wellbore axis and make the grinding shoe device (10) close to the inner wall of the wellbore; The drill pipe column (40) is driven to rotate around its axis by a rotary power device (70), and the drill pipe column (40) drives the hydraulic eccentric reducer stabilizer (30), the drill collar column (20) and the grinding shoe device (10) to rotate around the axis of the wellbore, so that the grinding shoe device (10) can grind the drilling and grinding working surface in the wellbore; After the milling is completed, the drilling and grinding fluid circulation device (80) is turned off to restore the hydraulic eccentric variable diameter stabilizer (30) to an initial state; The drilling and grinding pipe string is lifted from the wellbore by the traction and lifting equipment (60).

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