One-trip ultra-short radius sidetracking windowing tool

Abstract

The present application relates to a one-trip ultra-short radius sidetracking windowing tool, comprising a whipstock and a windowing mill, the whipstock is connected with the windowing mill through a first shear structure, the first shear structure can be sheared to make the whipstock and the windowing mill disengage; the whipstock comprises a whipstock body, a matching hole extending from the lower end to the upper end is formed in the whipstock body, an adjusting mechanism is arranged in the matching hole, the whipstock body is connected with the adjusting mechanism through a second shear structure, the second shear structure can be sheared, and after the second shear structure is sheared, the adjusting mechanism moves upward along the matching hole; a connecting structure is connected to the outer sidewall of the whipstock body, and the upward movement of the adjusting mechanism makes the connecting structure hang the whipstock body on the inner wall of the casing. The one-trip ultra-short radius sidetracking windowing tool can complete the whipstock hanging, the whipstock and the windowing mill disengaging and the windowing operation of the windowing mill through one-trip drilling, which shortens the operation time and reduces the drilling cost compared with the prior art.

Description

Technical Field

[0001] This invention belongs to the field of oilfield exploration and development technology, specifically relating to a one-pass ultra-short radius side drilling window opening tool. Background Technology

[0002] Oilfields exploited using water injection have entered a high water-cut stage. The remaining unexploited crude oil is not concentrated, but scattered in areas such as the top of thick oil layers, fault edges, and transition zones, making extraction difficult. To improve the efficiency of extracting the remaining crude oil and reduce the difficulty, existing technologies typically choose ultra-short radius sidetracking technology with a smaller radius of curvature to compensate for the limitations of single horizontal drilling technology.

[0003] In recent years, in the field of ultra-short radius side drilling window opening in China, two independent sets of tools, namely the directional drilling tool and the window opening grinding shoe, are used to complete the window opening through two trips of drilling. In the first trip, the directional drilling tool is sent in and hung in the well. After the drilling is pulled out, the window opening grinding shoe is sent in the second trip to open the window. After the window is opened, the drilling is pulled out again. Therefore, it has the disadvantages of long trip time, high operating cost, and high labor intensity for workers. Summary of the Invention

[0004] In order to solve all or part of the above problems, the present invention aims to provide a single-trip ultra-short radius side drilling window opening tool, which can realize the simultaneous installation and window opening operations in one trip of drilling.

[0005] According to one aspect of the present invention, a one-pass ultra-short radius side drilling window opening tool is provided, comprising a directional drilling tool and a window opening grinding shoe, wherein the directional drilling tool is connected to the window opening grinding shoe via a first shearing structure, the upper end of the window opening grinding shoe is used to connect to a flexible drill string, and the first shearing structure can be sheared to release the directional drilling tool from the window opening grinding shoe.

[0006] The swashplate includes a swashplate body, on which a mating hole extending upward from the lower end is provided. An adjustment mechanism is provided in the mating hole. The swashplate body is connected to the adjustment mechanism through a second shearing structure. The second shearing structure can be cut off, and after the second shearing structure is cut off, the adjustment mechanism moves upward along the mating hole.

[0007] A connecting structure is connected to the outer wall of the swashplate body. The adjustment mechanism moves upward so that the connecting structure hangs the swashplate body on the inner wall of the sleeve.

[0008] Furthermore, the connection structure includes an upper clamp and a lower clamp that are symmetrical about the axis of the swashplate body. The upper clamp is fixedly connected to the outer wall of the swashplate body, and the outer surface of the upper clamp is located outside the outer wall of the swashplate body. The swashplate body has a mounting groove, and the distance between the bottom wall of the mounting groove and the axis of the swashplate body gradually decreases from top to bottom. The lower clamp is slidably connected to the mounting groove. The upward movement of the adjustment mechanism can push the lower clamp to slide upward along the mounting groove to its limit position. When the lower clamp slides upward to its limit position, the upper clamp and the lower clamp cooperate to allow the swashplate body to be seated on the inner wall of the sleeve.

[0009] Furthermore, at least one dovetail-shaped groove extending from top to bottom is provided on the bottom wall of the mounting groove. The upper end of the dovetail-shaped groove is connected to a first limiting structure. The lower clamp is located in the mounting groove, and the lower end of the inner surface of the lower clamp is provided with a dovetail-shaped slider. The dovetail-shaped slider is located in the dovetail-shaped groove, and when the lower clamp slides upward to the limit position, the first limiting structure blocks the dovetail-shaped slider.

[0010] Furthermore, the upper slip is fixed to the outer wall of the diagonal body by an upper slip screw; both the upper slip and the lower slip have toothed structures on their outer surfaces; the first limiting structure is a lower slip positioning pin.

[0011] Furthermore, an outer cylinder is fixedly connected to the lower end of the inclined body, and a tail end cap is fixedly connected to the lower end of the outer cylinder. The adjusting mechanism includes an adjusting rod located in the mating hole. The adjusting rod and the tail end cap are connected through the second shearing structure. The tail end cap has a through hole for the adjusting rod to pass through. A connecting plate is fixedly connected to the adjusting rod. An elastic structure is provided between the tail end cap and the connecting plate. When the elastic structure is at its free length, the lower end of the adjusting rod extends out of the through hole. Before the second shearing structure is cut, the elastic structure is configured in a compressed state, and the compression of the elastic structure is sufficient to allow the adjusting rod to push the lower slip upward to its limit position.

[0012] Furthermore, a push rod is provided above the connecting plate, and the inclined body is provided with a push rod movable hole for the push rod to pass through. The push rod movable hole is connected to the mounting groove. After the second shearing structure is cut, the adjusting rod moves upward and pushes the lower clamp upward through the push rod.

[0013] Furthermore, the adjusting rod is provided with a shoulder with a diameter larger than the diameter of the through hole in the tail end cap. The shoulder is located inside the tail end cap, and the shoulder and the tail end cap are connected by the second shearing structure. The tail end cap above the shoulder is provided with a mating surface. The elastic structure is located between the mating surface and the connecting disc. When the elastic structure is at its free length, the vertical distance between the shoulder and the tail end cap is greater than or equal to the compression length required by the elastic structure when the lower slip moves from the lower end to the limit position.

[0014] Furthermore, the adjusting mechanism includes an adjusting rod located within the mating hole. The adjusting rod and the inclined plate body are connected via the second shearing structure. A first sealing ring and a second sealing ring are provided between the mating hole and the adjusting rod. Both the first and second sealing rings are fitted onto the adjusting rod. A sealed cavity is formed between the inclined plate body, the first sealing ring, the second sealing ring, and the adjusting rod. The first sealing ring is located above the second sealing ring, and a second limiting structure is provided within the mating hole below the second sealing ring. A third limiting structure is provided on the adjusting rod above the first sealing ring. When the pressure within the sealed cavity increases, the first sealing ring moves upward, pushing the third limiting structure and the adjusting rod upward. The upward movement of the adjusting rod causes the second shearing structure to be sheared.

[0015] Furthermore, a first connecting hole is provided on the side wall of the inclined body between the first sealing ring and the second sealing ring, and a water eye is provided inside the window-opening grinding shoe, extending downward from the top to the middle of the window-opening grinding shoe. A second connecting hole communicating with the water eye is provided on the side wall of the window-opening grinding shoe, and the first connecting hole and the second connecting hole are connected by a connecting pipe.

[0016] Furthermore, the mating hole includes a large-diameter section, a small-diameter section, and an intermediate section, wherein the intermediate section is located between the large-diameter section and the small-diameter section, the diameter of the intermediate section is larger than the diameter of the small-diameter section but smaller than the diameter of the large-diameter section, the small-diameter section mates with the adjusting rod, the first sealing ring is disposed within the intermediate section, the second sealing ring is disposed within the large-diameter section, and the upper part of the second sealing ring contacts the intermediate section; a sliding piston is sleeved on the adjusting rod between the first sealing ring and the second sealing ring, the upper end of the sliding piston is located above the first connecting hole.

[0017] Furthermore, the swashplate body has a connecting pipe mounting hole, which extends upward to penetrate the swashplate body and downward to communicate with the first connecting hole. The connecting pipe is disposed inside the connecting pipe mounting hole. The second limiting structure is an elastic retaining ring for the hole disposed on the inner wall of the mating hole. The third limiting structure is a convex ring disposed on the outside of the adjusting rod.

[0018] Furthermore, the upper end of the inclined body is provided with an inclined surface, and the upper end of the inclined surface is connected to an extension surface. The extension surface is connected to the window-opening grinding shoe through the first shearing structure. The first shearing structure includes a shearing bolt and a tightening screw. The tightening screw is connected to one end of the shearing bolt that passes through the extension and the window-opening grinding shoe. The second shearing structure consists of shearing pins.

[0019] As can be seen from the above technical solution, the one-pass ultra-short radius side drilling window opening tool provided by the present invention has the following beneficial effects:

[0020] The present invention provides a one-trip ultra-short radius side-drilling window-opening tool, which includes a window-opening grinding shoe and a directional drilling rig. The directional drilling rig is used to sit on the inner wall of the casing, and the window-opening grinding shoe is used to open the window. Thus, the sitting and hanging of the directional drilling rig, the release of the directional drilling rig from the window-opening grinding shoe, and the window-opening operation of the window-opening grinding shoe can be completed in one trip. Compared with the prior art, this shortens the operation time, reduces the labor intensity of workers, and reduces drilling costs. Attached Figure Description

[0021] Figure 1 This is a front view of a single-pass ultra-short radius side drilling window opening tool according to an embodiment of the present invention;

[0022] Figure 2 This is a right view of a single-pass ultra-short radius side drilling window opening tool according to an embodiment of the present invention;

[0023] Figure 3 This is a cross-sectional view of a single-pass ultra-short radius side drilling window opening tool according to an embodiment of the present invention;

[0024] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0025] Figure 5 for Figure 3 A magnified view of a section at point B in the middle;

[0026] Figure 6 This describes the operation process before opening a window using the window opening tool of this invention.

[0027] Figure 7 This is a schematic diagram of multi-branch well operations;

[0028] The attached figures are labeled as follows: 1. Flexible drill bit; 2. Window-opening grinding shoe; 3. First shearing structure; 4. Sliding piston; 5. Inclined surface; 51. Extension surface; 52. First connecting hole; 53. Mounting groove; 54. Upper slip; 6. Upper slip screw; 61. Lower slip positioning pin; 7. Lower slip; 8. Mating hole; 9. Small diameter section; 91. Middle section; 92. Large diameter section; 93. Adjusting rod; 10. Convex ring; 101. Shoulder; 102. First sealing ring; 11. Second sealing ring; 12. Hole elastic retaining ring; 13. Outer cylinder; 14. Push rod; 15. Connecting pipe; 16. Second shearing structure; 17. Tail end cap; 18. Mating surface; 181. Elastic structure; 19. Connecting disc; 20. Detailed Implementation

[0029] To better understand the purpose, structure, and function of this invention, the following detailed description of a one-pass ultra-short radius side drilling window opening tool of this invention is provided in conjunction with the accompanying drawings.

[0030] like Figures 1-3 As shown, it illustrates a one-pass ultra-short radius side drilling window opening tool according to an embodiment of the present invention, including a directional drilling tool and a window opening grinding shoe 2. The directional drilling tool is connected to the window opening grinding shoe 2 through a first shearing structure 3. The upper end of the window opening grinding shoe 2 is used to connect to the flexible drill string 1. The first shearing structure 3 can be sheared to release the directional drilling tool from the window opening grinding shoe 2.

[0031] In this embodiment, the directional drilling tool and the window-opening grinding shoe 2 are connected together by the first shearing structure 3. When in use, the window-opening tool is first sent to the window-opening position by the pre-connected drill bit. The section of the drill bit connected to the window-opening grinding shoe 2 is a flexible drill bit 1. After the window-opening tool is sent to the window-opening position, the directional drilling tool is first hung on the inner wall of the casing. Then, the drill bit applies a downward pressure to the window-opening grinding shoe 2 to cut the first shearing structure 3. After the first shearing structure 3 is cut, the window-opening grinding shoe 2 and the directional drilling tool are separated, and the window-opening grinding shoe 2 can be used to perform window-opening operations.

[0032] The window opening tool of this embodiment can complete the window opening operation in the next drilling run. Compared with the prior art where the window opening grinding shoe 2 and the directional tool are designed independently and require two drilling runs to complete the window opening operation, the operation time is shortened and the labor intensity of workers is reduced.

[0033] The inclined device includes an inclined device body 5, on which a mating hole 9 extending upward from the lower end is provided. An adjustment mechanism is provided in the mating hole 9. The inclined device body 5 is connected to the adjustment mechanism through a second shearing structure 17. The second shearing structure 17 can be cut off, and after the second shearing structure 17 is cut off, the adjustment mechanism moves upward along the mating hole 9. A connecting structure is connected to the outer wall of the inclined device body 5. The upward movement of the adjustment mechanism causes the connecting structure to hang the inclined device body 5 on the inner wall of the sleeve.

[0034] Specifically, the slant includes a slant body 5, an adjustment mechanism, and a connecting structure. The adjustment mechanism is located in the mating hole 9 of the slant body 5, and the slant body 5 and the adjustment mechanism are connected by a second shearing structure 17. The second shearing structure 17 can be cut. When the second shearing structure 17 is cut, the adjustment mechanism moves upward, and the upward movement of the adjustment mechanism drives the connecting structure to sit on the inner wall of the sleeve, thereby achieving the purpose of sitting on the inner wall of the sleeve.

[0035] In one embodiment, such as Figure 3 As shown, the connecting structure includes an upper slip 6 and a lower slip 8 that are symmetrical about the axis of the slanter body 5. The upper slip 6 is fixedly connected to the outer wall of the slanter body 5, and the outer surface of the upper slip 6 is located outside the outer wall of the slanter body 5. The slanter body has a mounting groove 54. The distance between the bottom wall of the mounting groove 54 and the axis of the slanter body 5 gradually decreases from top to bottom. The lower slip 8 is slidably connected to the mounting groove 54. The upward movement of the adjustment mechanism can push the lower slip 8 to slide upward along the mounting groove 54 to the limit position. After the lower slip 8 slides upward to the limit position, the upper slip 6 and the lower slip 8 cooperate to make the slanter body 5 sit on the inner wall of the sleeve.

[0036] In this embodiment, the upper slip 6 is fixedly connected to the outer wall of the swashplate body 5, and the outer surface of the upper slip 6 is located outside the outer wall of the swashplate body 5. In order for the swashplate with the upper slip 6 fixedly connected to be smoothly lowered into the sleeve, the maximum distance from the upper slip 6 to the other side of the swashplate body 5 needs to be less than the inner diameter of the sleeve.

[0037] The lower slip 8 is set in the mounting groove 54 on the inclined plate body 5, and the lower slip 8 can slide upward along the mounting groove 54 to the limit position. Since the mounting groove 54 is an inclined groove that gradually approaches the axis of the inclined plate body 5 from top to bottom, by adjusting the length of the inclined groove or the inclination of the inclined groove, it can be achieved that when the lower slip 8 is located at the lower end of the mounting groove 54, the outer surface of the lower slip 8 is located inside the outer wall of the inclined plate body 5. This design allows the window opening tool to be smoothly lowered into the sleeve.

[0038] Furthermore, as the lower slip 8 moves upward along the mounting groove 54, the outer surface of the lower slip 8 gradually moves to the outside of the outer wall of the deflector body 5, thereby gradually increasing the maximum distance between the lower slip 8 and the upper slip 6. When the lower slip 8 moves to the limit position, the lower slip 8 and the upper slip 6 cooperate to make the deflector body 5 sit and hang inside the sleeve.

[0039] In this embodiment, the lower slip 8 and the upper slip 6 are symmetrically arranged about the axis of the swashplate body 5, so that the swashplate body 5 can be more firmly mounted on the inner wall of the sleeve.

[0040] As an alternative, the upper slips 6 can be set to two or more distributed on the outer circumference of the directional diverter body 5. In order for the directional diverter body 5 to be smoothly lowered into the sleeve, the maximum angle of the fan-shaped area formed by all the upper slips 6 must be less than 180 degrees. The lower slips 8 are set at a position symmetrical to one of the upper slips 6 about the axis of the directional diverter body 5.

[0041] In one embodiment, at least one dovetail-shaped groove extending from top to bottom is provided on the bottom wall of the mounting groove 54. The upper end of the dovetail-shaped groove is connected to a first limiting structure. The lower clamp 8 is located in the mounting groove 54, and the lower end of the inner surface of the lower clamp 8 is provided with a dovetail-shaped slider. The dovetail-shaped slider is located in the dovetail-shaped groove, and when the lower clamp 8 slides upward to the limit position, the first limiting structure blocks the dovetail-shaped slider.

[0042] In this embodiment, the lower slip 8 slides within the mounting groove 54 through the cooperation of the dovetail slider and the dovetail groove. Specifically, the dovetail groove is formed on the bottom wall of the mounting groove 54, and the dovetail slider is disposed on the inner surface of the lower slip 8.

[0043] In addition, to limit the distance that the lower slip 8 slides upward along the mounting groove 54, a first limiting structure is provided at the upper end of the dovetail-shaped groove in this embodiment, and the dovetail-shaped slider is provided at the lower end of the lower slip 8. Therefore, when the dovetail-shaped slider slides upward along the dovetail-shaped groove with the lower slip 8, the dovetail-shaped slider gradually approaches the first limiting structure. When the lower slip 8 slides upward to the limit position, the first limiting structure blocks the dovetail-shaped slider, thereby limiting the distance that the lower slip 8 slides upward.

[0044] In this embodiment, during installation, first insert the dovetail slider into the dovetail groove, push the lower clip 8 to the lower end of the mounting groove 54, and finally fix the first limiting structure at the upper end of the dovetail groove.

[0045] Secondly, the dovetail-shaped groove can prevent the lower slip 8 from detaching from the inclined body 5 in the non-sliding direction. In specific implementation, multiple dovetail-shaped grooves can be set to be parallel to each other, and multiple dovetail-shaped sliders can also be set. As an alternative to the dovetail-shaped groove and dovetail-shaped slider, the dovetail-shaped groove can also be designed as a groove with other structures, and the cross-sectional shape of the slider can be changed accordingly, but it is necessary to ensure that the slider cannot detach from the groove in the non-sliding direction.

[0046] As an alternative to this embodiment, in a specific setting, the slider can also be set on the bottom wall of the mounting groove 54, and the sliding groove can be set on the inner surface of the lower slip 8. The sliding connection between the lower slip 8 and the inclined body 5 can also be achieved through the cooperation of the slider and the sliding groove. In this alternative, the first limiting structure can also be set on the bottom wall of the mounting groove 54, and the corresponding sliding groove is set on the inner surface of the lower slip 8. During the upward sliding of the lower slip 8, the first limiting structure is always in the sliding groove, and a limiting block is set at the bottom of the sliding groove. When the lower slip 8 slides upward to the limit position, the first limiting structure blocks the upper part of the limiting block.

[0047] In one embodiment, the upper slip 6 is fixed to the outer wall of the inclined body 5 by an upper slip screw 61; the outer surfaces of both the upper slip 6 and the lower slip 8 are provided with toothed structures; the first limiting structure is the lower slip positioning pin 7.

[0048] The upper slip 6 is fixed to the outer wall of the diagonal body 5 by the upper slip screw 61, which has the advantage of convenient connection; the toothed structure on the outer surface of the lower slip 8 and the upper slip 6 makes the engagement between the upper slip 6 and the lower slip 8 and the inner wall of the sleeve more secure; the first limiting structure is the positioning pin 7 of the lower slip 8, which has the advantage of convenient installation. As an alternative to the toothed structure, other barbed structures can also be set on the outer surface of the upper slip and the lower slip, so that the lower slip and the upper slip can sit on the inner wall of the sleeve.

[0049] In one embodiment, such as Figure 3 , Figure 5 As shown, the lower end of the inclined body 5 is fixedly connected to an outer cylinder 14, and the lower end of the outer cylinder 14 is fixedly connected to a tail end cap 18. The adjustment mechanism includes an adjustment rod 10 located in the mating hole 9. The adjustment rod 10 and the tail end cap 18 are connected by a second shearing structure 17. The tail end cap 18 is provided with a through hole for the adjustment rod 10 to pass through. A connecting plate 20 is fixedly connected to the adjustment rod 10. An elastic structure 19 is provided between the tail end cap 18 and the connecting plate 20. When the elastic structure 19 is at its free length, the lower end of the adjustment rod 10 extends out of the through hole. Before the second shearing structure 17 is cut, the elastic structure 19 is configured to be in a compressed state, and the compression of the elastic structure 19 is sufficient to push the lower slip 8 upward to its limit position.

[0050] In this embodiment, the inclined body 5, outer cylinder 14, and tail end cap 18 form a closed space. The adjustment mechanism includes an adjustment rod 10, which is located within the mating hole 9, and its lower end extends to be connected to the tail end cap 18 via a second shearing structure 17. A connecting plate 20 is located within the closed space and is fixed to the adjustment rod 10. An elastic structure 19 is disposed between the connecting plate 20 and the tail end cap 18. The tail end cap 18 has a through hole through which the adjustment rod 10 passes. Therefore, by adjusting the length of the adjustment rod 10 extending beyond the through hole, the distance between the connecting plate 20 and the tail end cap 18 can be changed, thereby compressing the elastic structure 19. To facilitate the adjustment of the adjustment rod 10, it is necessary to ensure that the lower end of the adjustment rod 10 extends beyond the through hole when the elastic structure 19 is at its free length.

[0051] Furthermore, the connecting disc 20 can only move upward with the adjusting rod 10 under the elastic force of the elastic structure 19. Therefore, in order for the adjusting rod 10 to push the lower slip 8 upward to the limit position, in this embodiment, the elastic force of the elastic structure 19 needs to be able to make the lower slip 8 slide upward to the limit position through the adjusting rod 10. The elastic force of the elastic structure 19 is changed by adjusting the adjusting rod 10. Therefore, during installation, it is necessary to first adjust the adjusting mechanism to change the compression amount of the elastic structure 19 according to the displacement of the lower slip 8 from the lower end to the limit position, so that the compression amount of the elastic structure 19 meets the requirement of the lower slip 8 moving upward.

[0052] Specifically, during installation, first adjust the length of the adjusting rod 10 extending out of the perforation according to the compression requirement of the elastic structure 19. Then, connect the adjusting rod 10 and the tail end cap 18 using the second shearing structure 17. The compression of the elastic structure 19 needs to be sufficient to allow the adjusting rod 10 to push the lower slip 8 upward to its limit position. After connecting the adjusting rod 10 and the tail end cap 18 using the second shearing structure 17, the elastic structure 19 is limited between the connecting plate 20 and the tail end cap 18, and the adjusting rod 10 cannot move. When the second shearing structure 17 is cut, the adjusting rod 10 moves upward under the elastic force of the elastic structure 19, thereby pushing the lower slip 8 upward to its limit position.

[0053] In addition, in specific implementation, the elastic structure 19 can be set as an elastic element such as a spring or disc spring, and the fixed connection between the connecting plate 20 and the adjusting rod 10 can be set as a threaded connection; the fixed connection between the inclined body 5 and the outer cylinder 14 can be set as a screw connection or a threaded connection; the fixed connection between the tail end cap 18 and the outer cylinder 14 can be set as a screw connection or a threaded connection.

[0054] In one embodiment, such as Figures 3-5As shown, a push rod 15 is provided above the connecting plate 20. The inclined body 5 is provided with a push rod movable hole for the push rod 15 to pass through. The push rod movable hole is connected to the mounting groove 54. After the second shearing structure 17 is cut, the adjusting rod 10 moves up and pushes the lower clamp 8 to slide upward through the push rod 15.

[0055] In this embodiment, the connecting plate 20 pushes the push rod 15 upward to push the lower slip 8 upward. Specifically, the push rod 15 is located above the connecting plate 20. The inclined body 5 is provided with a push rod movable hole, which is connected to the mounting groove 54. Therefore, when the connecting plate 20 moves upward, it pushes the push rod 15 upward along the push rod movable hole, and the push rod 15 pushes the lower slip 8 upward to slide.

[0056] In one embodiment, such as Figure 5 As shown, the adjusting rod 10 is provided with a shoulder 102 with a diameter larger than the diameter of the through hole of the tail end cover 18. The shoulder 102 is located inside the tail end cover 18. The shoulder 102 and the tail end cover 18 are connected by the second shearing structure 17. The tail end cover 18 above the shoulder 102 is provided with a mating surface 181. The elastic structure 19 is located between the mating surface 181 and the connecting plate 20. When the elastic structure 19 is in its free length, the vertical distance between the shoulder 102 and the tail end cover 18 is greater than or equal to the height of the lower slip moving upward from the lower end to the limit position.

[0057] In this embodiment, the adjusting rod 10 is provided with a shoulder 102. The shoulder 102 is located inside the tail end cap 18, and the diameter of the shoulder 102 is larger than the diameter of the through hole in the tail end cap 18. Therefore, the shoulder 102 on the adjusting rod 10 cannot pass through the through hole in the tail end cap 18 and move downward. As mentioned above, the elastic structure 19 is disposed between the connecting plate 20 and the tail end cap 18. Specifically, the tail end cap 18 is provided with a mating surface 181, which is located above the shoulder 102. The elastic structure 19 is limited between the connecting plate 20 and the mating surface 181. In specific configuration, the shoulder 102 can be configured as an integral structure with the adjusting rod 10, or the shoulder can be configured as a structure fixedly connected to the adjusting rod 10.

[0058] Furthermore, since the presence of the shoulder 102 affects the length of the adjusting rod 10 that is allowed to extend beyond the perforation, this embodiment needs to satisfy the following: when the elastic structure 19 is in its free length, the vertical distance between the shoulder 102 and the tail end cap 18 is greater than or equal to the compression length required by the elastic structure when the lower slip moves from the lower end to the limit position.

[0059] Specifically, during installation, first adjust the adjusting rod 10 so that the shoulder 102 and the tail end cap 18 contact each other. Then, use the second shearing structure 17 to connect the adjusting rod 10 and the tail end cap 18. When the second shearing structure 17 is cut, the elastic force of the elastic structure 19 pushes the lower slip 8 upward through the push rod 15. When the vertical distance between the shoulder 102 and the tail end cap 18 is greater than the compression length required by the elastic structure when the lower slip moves from the bottom to the limit position, the elastic structure 19 pushes the lower slip 8 upward to the limit position. The remaining elastic force acts on the lower slip 8, making the seating between the lower slip 8 and the inner wall of the sleeve more secure. When the vertical distance between the shoulder 102 and the tail end cap 18 is equal to the compression length required by the elastic structure when the lower slip moves from the bottom to the limit position, the elastic structure 19 can just overcome the friction between the lower slip 8 and the sleeve and push the lower slip 8 upward to the limit position.

[0060] In one embodiment, such as Figures 3-4 As shown, the adjustment mechanism includes an adjustment rod 10 located in the mating hole 9. The adjustment rod 10 and the inclined body 5 are connected by a second shearing structure 17. A first sealing ring 11 and a second sealing ring 12 are provided between the mating hole 9 and the adjustment rod 10. The first sealing ring 11 and the second sealing ring 12 are both sleeved on the adjustment rod 10. A sealed cavity is formed between the inclined body 5, the first sealing ring 11, the second sealing ring 12 and the adjustment rod 10. The first sealing ring 11 is located above the second sealing ring 12, and a second limiting structure is provided in the mating hole 9 below the second sealing ring 12. A third limiting structure is provided on the adjustment rod 10 above the first sealing ring 11. When the pressure in the sealed cavity increases, the first sealing ring 11 moves upward, pushing the third limiting structure and the adjustment rod 10 upward. The upward movement of the adjustment rod 10 causes the second shearing structure 17 to be sheared.

[0061] Specifically, in this embodiment, the adjustment mechanism includes an adjustment rod 10. A first sealing ring 11 and a second sealing ring 12 are provided between the adjustment rod 10 and the mating hole 9. The first sealing ring 11 and the second sealing ring 12 are both sleeved on the adjustment rod 10. The first sealing ring 11 is sealed to the inner wall of the adjustment rod 10 and the mating hole 9, respectively. The second sealing ring 12 is sealed to the inner wall of the adjustment rod 10 and the mating hole 9, respectively, so that a sealed cavity is formed between the inclined body 5, the first sealing ring 11, the second sealing ring 12 and the adjustment rod 10.

[0062] Secondly, in this embodiment, the first sealing ring 11 is located above the second sealing ring 12, and a second limiting structure is provided in the mating hole 9 below the second sealing ring 12. The second limiting structure is used to prevent the second sealing ring 12 from moving downward, thus preventing the second sealing ring 12 from passing through the second limiting structure and moving downward. A third limiting structure is provided on the adjusting rod 10 above the first sealing ring 11, which is used to prevent the first sealing ring 11 from moving upward relative to the adjusting rod 10. Therefore, when the pressure in the sealing cavity increases, the first sealing ring 11 will move upward together with the adjusting rod 10, and the upward movement of the adjusting rod 10 will cause the second shearing structure 17 to be sheared.

[0063] Furthermore, in specific configurations, the second limiting structure can be an elastic retaining ring 13 fixed to the inner wall of the mating hole 9; the third limiting structure can be a convex ring 101 integrally formed on the outside of the adjusting rod 10, or a retaining ring fixed on the outside of the adjusting rod 10. When the third limiting structure is a convex ring 101 integrally formed on the outside of the adjusting rod 10, and the shoulder 102 is integrally formed on the lower part of the adjusting rod 10, the adjusting rod 10 will be thick at both ends and thin in the middle. Therefore, in order to facilitate the installation of the first sealing ring 11, the second sealing ring 12 and the connecting plate 20 on the adjusting rod 10, the adjusting rod 10 can be divided into upper and lower sections, and both sections can be fixedly connected to the connecting plate 20, for example, by threading both sections to the connecting plate 20.

[0064] In one embodiment, such as Figures 3-4 As shown, a first connecting hole 53 is provided on the side wall of the inclined body 5 between the first sealing ring 11 and the second sealing ring 12. A water eye is provided inside the window-opening grinding shoe 2, extending downward from the top to the middle of the window-opening grinding shoe 2. A second connecting hole communicating with the water eye is provided on the side wall of the window-opening grinding shoe 2. The first connecting hole 53 and the second connecting hole are connected by a connecting pipe 16.

[0065] In this embodiment, the high-pressure liquid is injected into the sealed cavity through the water hole, the second connecting hole, the connecting pipe 16, and the first connecting hole 53 on the window-opening grinding shoe 2, thereby increasing the pressure in the sealed cavity. Specifically, the connecting pipe 16 can be made of a relatively soft copper pipe. During the process of the drilling tool being pressed down to shear the first shearing structure 3, the connecting pipe breaks under pressure, and the part of the connecting pipe connected to the window-opening grinding shoe is milled off during the window-opening operation of the grinding shoe.

[0066] In one embodiment, such as Figure 4As shown, the mating hole 9 includes a large-diameter section 93, a small-diameter section 91, and an intermediate section 92. The intermediate section 92 is located between the large-diameter section 93 and the small-diameter section 91. The diameter of the intermediate section 92 is larger than the diameter of the small-diameter section 91 but smaller than the diameter of the large-diameter section 93. The small-diameter section 91 mates with the adjusting rod 10. The first sealing ring 11 is disposed inside the intermediate section 92, and the second sealing ring 12 is disposed inside the large-diameter section 93. The upper part of the second sealing ring 12 contacts the intermediate section 92. A sliding piston 4 is sleeved on the adjusting rod 10 between the first sealing ring 11 and the second sealing ring 12. The upper end of the sliding piston 4 is located above the first connecting hole 53.

[0067] In this embodiment, the mating hole 9 is divided into an upper small-diameter section 91, a lower large-diameter section 93, and an intermediate section 92 located between the large-diameter section 93 and the small-diameter section 91. The diameter of the small-diameter section 91 matches the diameter of the adjusting rod 10 to guide the movement of the adjusting rod 10. The first sealing ring 11 is disposed in the intermediate section 92. The first sealing ring 11 can slide upward along the intermediate section 92, and the intermediate section 92 also limits the second sealing ring 12 below it, preventing the second sealing ring 12 from sliding upward.

[0068] The sliding piston 4 is positioned between the first sealing ring 11 and the second sealing ring 12. The sliding piston 4 can limit the position of the first sealing ring, preventing it from moving down below the first connecting hole 53, thereby ensuring that the pressurizing medium can smoothly enter the sealing cavity.

[0069] In one embodiment, such as Figure 1 , Figure 3 As shown, the upper end of the inclined surface 5 of the inclined surface body 5 is provided with an inclined surface 51, and the upper end of the inclined surface 51 is connected to an extension surface 52. The extension surface 52 is connected to the windowed grinding shoe 2 through the first shearing structure 3; as shown Figure 3 As shown, the first shearing structure 3 includes a shearing bolt and a tightening screw, with the tightening screw connected to one end of the shearing bolt that passes through the extension and the windowed grinding shoe 2; the second shearing structure 17 consists of shearing pins.

[0070] In specific settings, the angle between the screw hole on the tail end cap 18 that mates with the shear pin and the surface of the tail end cap 18 can be kept at a right angle, thereby accelerating the shearing of the shear pin. The number of shear pins can be set according to actual needs.

[0071] Furthermore, since the upper end of the window-opening grinding shoe in this embodiment is connected to the flexible drilling tool, the inclined surface 51 in this embodiment is relatively short to meet the operational requirements. Specifically, the length of the inclined surface 51 in this embodiment is about 1 meter to meet the operational requirements, while the inclined surface of the directional tool connected to the ordinary drilling tool (non-flexible drilling tool) in the prior art is about 5 meters to meet the operational requirements. Therefore, when the slopes of the two inclined surfaces are equal, the radius of the directional tool corresponding to the inclined surface in this embodiment is much smaller than the radius of the directional tool corresponding to the prior art, which reflects that the window-opening tool in this embodiment is an ultra-short radius window-opening tool.

[0072] In practical implementation, the first shearing structure 3 can also be configured to include a shearing bolt and a matching nut, with the matching nut also connected to the end of the shearing bolt that passes through the extension and the windowed grinding shoe 2. Furthermore, washers can be fitted onto both ends of the shearing bolt as needed.

[0073] To facilitate understanding of the working principle of the embodiments of the present invention, the embodiments of the present invention are described in detail below:

[0074] This invention's embodiment of a one-pass ultra-short radius side-drilling window-opening tool includes a window-opening grinding shoe 2 and a directional drilling rig. The directional drilling rig includes a directional drilling rig body 5, which is connected to an adjusting rod 10 of an adjusting mechanism via a second shearing structure 17. A sealed cavity is formed between the adjusting rod 10 and the directional drilling rig body 5. When pressure is applied into the sealed cavity through the drill string and connecting pipe 16, the adjusting rod 10 can be moved upwards, causing the second shearing structure 17 to be sheared. Before the second shearing structure 17 is sheared... An elastic structure 19 is provided between the tail end cap 18 and the connecting plate 20, and the elastic structure 19 is in a compressed state. Therefore, when the second shearing structure 17 is cut, the adjusting rod 10 and the connecting plate 20 move upward. The upward movement of the connecting plate 20 pushes the push rod 15 upward. The upward movement of the push rod 15 pushes the lower slip 8 upward. The elastic force of the elastic structure 19 causes the lower slip 8 to move upward to the limit position. After the lower slip 8 moves upward to the limit position, the upper slip 6 and the lower slip 8 cooperate to hang the inclinometer on the inner wall of the sleeve.

[0075] The directional drill bit and the window-opening grinding shoe 2 are connected by the first shearing structure 3. Cutting the first shearing structure 3 can release the directional drill bit from the window-opening grinding shoe 2. After the directional drill bit is hung on the inner wall of the casing, the first shearing structure 3 can be cut by pressing the drill bit down. After the first shearing structure 3 is cut, the window-opening operation can be performed through the window-opening grinding shoe 2.

[0076] The following uses a 9-5 / 8” casing as an example to illustrate the operation procedure before window opening when the one-pass ultra-short radius side-drilling window opening tool of this embodiment of the invention is used for window opening. Figure 6 As shown, the specific items include:

[0077] Connect the drill string, and after the drill string connection is completed, measure the angle difference and length.

[0078] Use a small-diameter drill pipe to connect with the drill string, and use a well gauge to circulate the well before insertion to ensure that the depth calibration tool and directional gyroscope can be successfully inserted into the well.

[0079] The drill string assembly is fed into the window position at a limited speed. The depth of the directional drill is made accurate by gamma correction, and the orientation of the directional drill is made accurate by gyro orientation. The drill string is lifted more than 5m to release the torque, and the orientation is repeatedly checked to ensure accuracy.

[0080] The drill pipe is pressurized, and the pressurization pressure is determined by the pressure that the second shearing structure 17 can shear, for example, 25MPa. The pressure is stabilized for 15 minutes, and the pressurization is repeated to ensure that the directional device is smoothly mounted on the inner wall of the casing.

[0081] The load was increased by 20kN and decreased by 80kN on the original tubing load to test the hanger, ensuring that the directional device was successfully hung on the inner wall of the casing.

[0082] Applying pressure generates a separation force of 100-120kN, causing the window-opening grinding shoe 2 to separate from the inclined device. The window-opening grinding shoe 2 can then be used to open the window.

[0083] After the wellbore is opened, the original wellbore structure needs to be restored, and the directional drilling rig needs to be retrieved. The directional drilling rig is retrieved using a special directional drilling rig retrieval cone. The tubing string assembly from bottom to top is: special directional drilling rig retrieval cone + drill string. The retrieval method involves lowering a special retrieval tool. After reaching 1m above the directional drilling rig, the lower end of the retrieval string's connecting cone forcibly snaps into place at the top of the directional drilling rig, pulling it out. During the upward lifting of the directional drilling rig, the lower slip 8 is retracted by the downward friction of the casing, causing the directional drilling rig to detach from the wellbore. Specifically, start the pump and circulate it in the forward direction while rotating the drill string to repeatedly clean the directional drilling rig's retrieval window. At the same time, lower the retrieval tool. Once it reaches the directional drilling rig's position, lift it up 10-20cm, increase the displacement, and keep the pressure below 15MPa. Circulate for at least 30 minutes to ensure that all solid impurities are removed. Keep the drilling pressure below 2t and rotate the drill string in the forward direction until the torque suddenly increases and you stop rotating. Lift the drill string and carefully observe the changes in the suspended weight. Repeat lifting and lowering the drill string until the upper slip 6 and lower slip 8 are completely released. Limit the tripping speed to 20 drill bits / hour and pull out the directional drilling rig.

[0084] During multi-branch well operations, the directional drilling rig is mounted at the lowest window position. After the window is opened, the directional drilling rig is not immediately retrieved; instead, a stacked directional drilling rig is deployed above it. The window opening, directional drilling, and horizontal drilling processes are then sequentially initiated to complete the second borehole construction. This cycle is repeated for N boreholes, where N is greater than 1. Figure 7 As shown, after the window opening operation of the last layer is completed, all directional drilling tools are retrieved, thereby improving the side-drilling efficiency of multi-branch wells.

[0085] When operating multi-branch wells, accurate depth and orientation are required for each window opening. The specific method is as follows: based on the lowest-level directional drilling rig, a drill pipe of the required length is stacked and configured, the inclined plane is coupled with the directional drilling rig of the previous level, and then the position of the current-level directional drilling rig is accurately determined by gamma correction.

[0086] The orientation process is the same as before, using gyro orientation; after the directional tool reaches the designed orientation, the drill string is raised more than 5m to release the torque, and the orientation is repeatedly confirmed to ensure accuracy.

[0087] When conducting multi-branch well operations, the drilling tool combination method from bottom to top is: stacked directional tools, multi-stage grinding shoes, and flexible drill pipe.

[0088] The specific steps for multi-branch well operations are as follows: First, lower the stacked directional drilling rig, pre-fabricated according to the elevation difference and angle. Second, lower the drill string at a limited speed. Third, connect one drill string to the square drill pipe in advance and lower the drill string to 1.5m above the opening position. Fourth, start the pump to flush the directional drilling rig. Fifth, apply 1-2T of pressure to probe the bottom. If the suspended weight remains unchanged, continue applying pressure until the lowering encounters resistance. Sixth, lift the drill string and reverse the drill string 90-180 degrees, repeatedly probing the depth of resistance. Seventh, attempt to reverse the drill string; if the resistance position remains unchanged, confirm successful stacking. Eighth, confirm the directional drilling rig is firmly seated and slowly rotate the drill string to release the stacked directional drilling rig and the opening shoe 2. After the single-hole construction is completed, the stacked directional drilling rig is deployed, and the opening, directional drilling, and horizontal drilling processes are started sequentially to complete the second hole construction. This cycle is repeated for N holes. Finally, the stacked directional drilling rig is retrieved sequentially to complete the multi-branch opening operation.

[0089] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0090] Furthermore, the terms "a," "two," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0091] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A one-pass ultra-short radius side drilling window opening tool, characterized in that, It includes a slant and a windowed grinding shoe. The slant is connected to the windowed grinding shoe via a first shearing structure. The upper end of the windowed grinding shoe is used to connect to a flexible drill bit. The first shearing structure can be cut to release the slant from the windowed grinding shoe. The swashplate includes a swashplate body, on which a mating hole extending upward from the lower end is provided. An adjustment mechanism is provided in the mating hole. The swashplate body is connected to the adjustment mechanism through a second shearing structure. The second shearing structure can be cut off, and after the second shearing structure is cut off, the adjustment mechanism moves upward along the mating hole. A connecting structure is connected to the outer wall of the swashplate body. The adjustment mechanism moves upward so that the connecting structure hangs the swashplate body on the inner wall of the sleeve. The connection structure includes an upper clamp and a lower clamp that are symmetrical about the axis of the swashplate body. The upper clamp is fixedly connected to the outer wall of the swashplate body, and the outer surface of the upper clamp is located outside the outer wall of the swashplate body. The swashplate body has a mounting groove, and the distance between the bottom wall of the mounting groove and the axis of the swashplate body gradually decreases from top to bottom. The lower clamp is slidably connected to the mounting groove. The upward movement of the adjustment mechanism can push the lower clamp to slide upward along the mounting groove to its limit position. When the lower clamp slides upward to its limit position, the upper clamp and the lower clamp cooperate to allow the swashplate body to be seated on the inner wall of the sleeve. The lower end of the inclined body is fixedly connected to an outer cylinder, and the lower end of the outer cylinder is fixedly connected to a tail end cap. The adjustment mechanism includes an adjustment rod located in the mating hole. The adjustment rod and the tail end cap are connected by a second shearing structure. The tail end cap has a through hole for the adjustment rod to pass through. A connecting plate is fixedly connected to the adjustment rod. An elastic structure is provided between the tail end cap and the connecting plate. When the elastic structure is at its free length, the lower end of the adjustment rod extends out of the through hole. Before the second shearing structure is cut, the elastic structure is configured in a compressed state, and the compression of the elastic structure is sufficient to allow the adjustment rod to push the lower slip upward to its limit position.

2. The single-pass ultra-short radius side drilling window opening tool according to claim 1, characterized in that, At least one dovetail-shaped groove extending from top to bottom is provided on the bottom wall of the mounting groove. The upper end of the dovetail-shaped groove is connected to a first limiting structure. The lower clamp is located in the mounting groove, and the lower end of the inner surface of the lower clamp is provided with a dovetail-shaped slider. The dovetail-shaped slider is located in the dovetail-shaped groove. When the lower clamp slides upward to the limit position, the first limiting structure blocks the dovetail-shaped slider.

3. The single-pass ultra-short radius side drilling window opening tool according to claim 2, characterized in that, The upper slip is fixed to the outer wall of the deflector body by an upper slip screw; both the upper slip and the lower slip have toothed structures on their outer surfaces; the first limiting structure is a lower slip positioning pin.

4. The single-pass ultra-short radius side drilling window opening tool according to claim 1, characterized in that, A push rod is provided above the connecting plate, and the inclined body is provided with a push rod movable hole for the push rod to pass through. The push rod movable hole is connected to the mounting groove. After the second shearing structure is cut, the adjusting rod moves upward and pushes the lower clamp upward through the push rod.

5. The single-pass ultra-short radius side drilling window opening tool according to claim 4, characterized in that, The adjusting rod has a shoulder with a diameter larger than the diameter of the through hole in the tail end cap. The shoulder is located inside the tail end cap, and the shoulder and the tail end cap are connected by the second shearing structure. The tail end cap above the shoulder has a mating surface. The elastic structure is located between the mating surface and the connecting disc. When the elastic structure is at its free length, the vertical distance between the shoulder and the tail end cap is greater than or equal to the compression length required by the elastic structure when the lower slip moves from the lower end to the limit position.

6. The single-pass ultra-short radius side-drilling window-opening tool according to claim 1, characterized in that, The adjusting mechanism includes an adjusting rod located within the mating hole. The adjusting rod and the inclined plate body are connected via the second shearing structure. A first sealing ring and a second sealing ring are provided between the mating hole and the adjusting rod. Both the first and second sealing rings are fitted onto the adjusting rod. A sealed cavity is formed between the inclined plate body, the first sealing ring, the second sealing ring, and the adjusting rod. The first sealing ring is located above the second sealing ring, and a second limiting structure is provided within the mating hole below the second sealing ring. A third limiting structure is provided on the adjusting rod above the first sealing ring. When the pressure within the sealed cavity increases, the first sealing ring moves upward, pushing the third limiting structure and the adjusting rod upward. The upward movement of the adjusting rod causes the second shearing structure to be sheared.

7. The single-pass ultra-short radius side drilling window opening tool according to claim 6, characterized in that, A first connecting hole is provided on the side wall of the inclined body between the first sealing ring and the second sealing ring. A water eye is provided inside the window-opening grinding shoe, extending downward from the top to the middle of the window-opening grinding shoe. A second connecting hole is provided on the side wall of the window-opening grinding shoe, communicating with the water eye. The first connecting hole and the second connecting hole are connected by a connecting pipe.

8. The single-pass ultra-short radius side drilling window opening tool according to claim 7, characterized in that, The mating hole includes a large-diameter section, a small-diameter section, and an intermediate section. The intermediate section is located between the large-diameter section and the small-diameter section. The diameter of the intermediate section is larger than the diameter of the small-diameter section but smaller than the diameter of the large-diameter section. The small-diameter section mates with the adjusting rod. The first sealing ring is disposed within the intermediate section, and the second sealing ring is disposed within the large-diameter section, with the upper part of the second sealing ring contacting the intermediate section. A sliding piston is sleeved on the adjusting rod between the first sealing ring and the second sealing ring, and the upper end of the sliding piston is located above the first connecting hole.

9. The single-pass ultra-short radius side drilling window opening tool according to claim 7, characterized in that, The swashplate body has a connecting pipe mounting hole, which extends upward to penetrate the swashplate body and downward to communicate with the first connecting hole. The connecting pipe is disposed inside the connecting pipe mounting hole. The second limiting structure is an elastic retaining ring for the hole disposed on the inner wall of the mating hole. The third limiting structure is a convex ring disposed on the outside of the adjusting rod.

10. The single-pass ultra-short radius side-drilling window-opening tool according to any one of claims 1-9, characterized in that, The upper end of the inclined plate body is provided with an inclined surface, and the upper end of the inclined surface is connected to an extension surface. The extension surface is connected to the window-opening grinding shoe through the first shearing structure. The first shearing structure includes a shearing bolt and a tightening screw. The tightening screw is connected to the end of the shearing bolt that passes through the extension surface and the window-opening grinding shoe. The second shearing structure consists of shearing pins.

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