Stable repairing tool for shaft

Abstract

The utility model discloses a wellbore stability repairing tool which comprises a drill column, a drill rod, a drill rod and a drill rod body. The reducing section is coaxial with the drill column, and the outer diameter of the reducing section is smaller than that of the drill column; the two blade structures are arranged on the surface of the reducing section; the two blade structures are arranged in the axial direction of the drill column in a spaced mode and symmetrically arranged in the radial direction of the drill column. The cutter wing structure is designed to be slightly eccentric, a well hole with the diameter slightly larger than the theoretical diameter of a drill bit is expanded when the cutter wing structure rotates along with drilling, spiral irregular well holes, well wall micro steps and micro dog legs are repaired, repeated tripping is not needed, and drilling efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas well repair tools, in particular to a wellbore stabilization repair tool. Background Art

[0002] In the drilling of extended-reach wells and horizontal wells, especially the sliding drilling of bent screws, it is easy to form spiral irregular wellbores, with prominent micro-steps and micro-doglegs on the well wall, resulting in the actual wellbore diameter being smaller than the expected wellbore, causing increased friction torque and reduced mechanical drilling speed; on the other hand, it will cause difficulties in the later electrical measurement and casing lowering, and cuttings and collapsed blocks are easily deposited on the low side of the wellbore with high inclination and horizontal sections. The flow of drilling fluid on the high side has a poor effect on the rising and migration of cuttings. As long as the pump is stopped, the cuttings will sink to the bottom immediately. Although the drilling tool rotation and concentric cuttings bed remover can disturb the cuttings bed, the cuttings bed problem is still prominent in the well section with severe micro-doglegs, which will also aggravate the friction torque that hinders drilling and causing difficulty in well clearance. Spiral wellbores and cuttings beds require frequent eye-reaming to prevent downhole accidents such as drill sticking. The current method to solve the spiral irregular wellbore, micro-steps on the well wall, and micro-doglegs is to repair the wellbore by reaming and expanding the hole after drilling. Although this can solve the above problems, it has the problem of many trips and low efficiency. Utility Model Content

[0003] In order to solve the above problems, the present application provides a wellbore stabilization repair tool, which can repair spiral irregular wellbores, micro-steps and micro-doglegs on the well wall, and improve drilling efficiency without multiple trips.

[0004] The purpose of the utility model is achieved through the following technical solutions: a wellbore stabilization repair tool, comprising:

[0005] A drill string is provided with a reduced diameter section; the reduced diameter section is coaxial with the drill string, and the outer diameter of the reduced diameter section is smaller than the outer diameter of the drill string.

[0006] Two blade structures are arranged on the surface of the reduced diameter section; the two blade structures are arranged at intervals along the axial direction of the drill string and are symmetrically arranged in the radial direction of the drill string.

[0007] The blade structure includes at least one reaming blade and at least one straightening blade evenly arranged in sequence on the reduced diameter section in the circumferential direction; the height of the straightening blade is less than the height of the reaming blade, and the height of the straightening blade and the height of the reaming blade on one blade structure gradually decreases in the direction away from the other blade structure to form an inclined surface, and a plurality of PDC cutting teeth are welded on the inclined surface at intervals along the extension direction of the inclined surface; the straightening blade and the reaming blade at least partially protrude from the outer surface of the drill string, and the extension line of the outer surface of the drill string can fall on one of the PDC cutting teeth.

[0008] Furthermore, the surfaces of the reaming blade and the straightening blade are both built-up with a tungsten carbide layer, and the tungsten carbide layer encases the welding part of the PDC cutting tooth.

[0009] As a preferred solution, the cutting edge height of the PDC cutting tooth is 5 mm.

[0010] As a preferred solution, the reaming blade and the straightening blade both extend in a spiral shape.

[0011] As a preferred solution, the spiral angles of the reaming blade and the straightening blade are both 8°.

[0012] As a preferred solution, both the reaming blade and the straightening blade are provided with gauge plates.

[0013] As a preferred solution, both the reaming blade and the straightening blade are provided with shock absorbing teeth, and the shock absorbing teeth are close to the gauge plate.

[0014] Compared with the prior art, this application has the following beneficial effects:

[0015] (1) The blade structure of the utility model is slightly eccentric in design. When it rotates with drilling, it expands the wellbore to a diameter slightly larger than the theoretical diameter of the drill bit, so as to repair the spiral irregular wellbore, micro-steps on the well wall and micro-doglegs, and it does not need to trip the drill multiple times, thereby improving the drilling efficiency.

[0016] (2) The blade structure of the utility model is arranged on the reduced diameter section, and the extension line of the outer surface of the drill string can fall on one of the PDC cutting teeth. When the tool is drilled along with the drill bit, the blade will not directly contact the well wall, which effectively protects the blade and improves the service life of the tool.

[0017] (3) The utility model has a tungsten carbide layer welded on the blade, which can increase the wear resistance of the blade and encase the PDC cutting teeth to prevent the PDC cutting teeth from falling off.

[0018] (4) The utility model is provided with shock-absorbing teeth, which can protect the gauge plate.

[0019] Some additional features of the present application may be explained in the following description. Some additional features of the present application will be apparent to those skilled in the art by inspection of the following description and corresponding drawings or understanding of the production or operation of the embodiments. The features disclosed in the present application may be realized and achieved by practice or use of various methods, means and combinations of the specific embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The exemplary embodiments of the present application and their descriptions are used to explain the present application and do not constitute a limitation of the present application. In each figure, the same reference numeral represents the same component.

[0021] Figure 1 It is the front view of the utility model.

[0022] Figure 2 It is a side view of the utility model.

[0023] Figure 3 It is a schematic diagram of the blade structure of the utility model being arranged in the reduced diameter section.

[0024] The reference numerals in the above-mentioned figures are: 1-drill string, 2-reducing section, 3-blade structure, 4-gauge plate, 5-PDC cutting tooth, 6-reaming blade, 7-straightening blade. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0026] Example

[0027] like Figure 1 As shown, this embodiment discloses a wellbore stabilization repair tool, which includes a drill string 1 and two blade structures 3. Among them, a reduced diameter section 2 is provided on the drill string 1, and the reduced diameter section 2 is coaxial with the drill string 1, and the outer diameter of the reduced diameter section 2 is smaller than the outer diameter of the drill string 1; that is, a portion of the position on the drill string 1 is concave inward in the radial direction, thereby forming the reduced diameter section 2, so that the outer diameter of the reduced diameter section 2 is smaller than the outer diameter of other positions of the drill string 1. Connecting structures are provided at both ends of the drill string 1, and the two ends are respectively connected to the drill tool through the connecting structures, so that the entire tool can be drilled or pulled out of the drill together with the drill tool, so as to repair the well wall while drilling, shorten the drilling cycle, avoid multiple drilling and pulling, and improve the drilling efficiency. Specifically, the connecting structures at both ends of the drill string 1 can be snaps or threads, that is, the drill string 1 can be connected to the drill tool by snapping or threading.

[0028] Two blade structures 3 are arranged on the surface of the reduced diameter section 2; when arranged, the two blade structures 3 are arranged at intervals along the axial direction of the drill string 1 and are arranged symmetrically in the radial direction of the drill string 1. In this way, the wellbore stabilization repair tool can perform hole enlargement when moving in both the upward and downward directions following the drilling tool, thereby improving the hole enlargement efficiency.

[0029] like Figure 2As shown, the blade structure 3 includes at least one reaming blade 6 and at least one straightening blade 7 which are uniformly arranged on the reduced diameter section 2 in sequence in the circumferential direction. In this embodiment, the number of reaming blades 6 and straightening blades 7 is set to two, and the two reaming blades 6 are adjacent, and the two straightening blades 7 are adjacent. The height of the straightening blade 7 is less than the height of the reaming blade 6, so that the entire blade structure 3 forms a micro-eccentric structure relative to the central axis of the drill string 1, so that when the wellbore stability repair tool rotates with the drill bit, the wellbore stability repair tool can achieve reaming to repair the spiral irregular wellbore, micro-steps on the well wall, and micro-doglegs.

[0030] The reaming blade 6 and the straightening blade 7 both extend in a spiral shape. Since the two blade structures 3 are symmetrically arranged in the radial direction of the drill string 1, the spiral directions of the reaming blade 6 and the straightening blade 7 on the two blade structures 3 are opposite, which can achieve autonomous force balance during tool operation.

[0031] As another implementation of this embodiment, the spiral angles of the reaming blade 6 and the straightening blade 7 are both set to 8°.

[0032] In addition, the height of the straightening blade 7 and the height of the reaming blade 6 on one blade structure 3 gradually decreases in the direction away from the other blade structure 3 to form an inclined surface, on which a plurality of PDC cutting teeth 5 are welded at intervals along the extending direction of the inclined surface. Figure 1 The straightening blade 7 and the reaming blade 6 at least partially protrude from the outer surface of the drill string 1, and the extended line of the outer surface of the drill string 1 can fall on one of the PDC cutting teeth 5. In this embodiment, the extended line of the outer surface of the drill string 1 can fall on the PDC cutting tooth 5 at the bottom of the inclined surface. Figure 3 As shown. During the manufacturing process, when the PDC cutting teeth 5 are arranged, the positions of the straightening blade 7 and the reaming blade 6 close to the surface of the drill string 1 cannot be arranged due to the obstruction of the drill string 1 or the welding process, resulting in limited coverage of the PDC cutting teeth 5. At this time, the positions of the blades close to the surface of the drill string 1 are exposed. When the tool is working, this part of the position will directly contact the well wall and be easily worn, affecting the service life of the tool. Therefore, in this embodiment, the blade structure 3 is arranged in the reduced diameter section 2, and the extended line of the outer surface of the drill string 1 can fall on the PDC cutting tooth 5 at the bottom of the inclined surface. In this way, the positions of the straightening blade 7 and the reaming blade 6 close to the surface of the reduced diameter section 2 will be protected by the reduced diameter section 2 and will not directly contact the well wall. When the tool is moving up or down, the well wall that needs to be expanded first contacts the bottom PDC cutting tooth 5. The protection of the PDC cutting tooth 5 prevents the straightening blade 7 and the reaming blade 6 from excessive wear.

[0033] In addition, the surfaces of the reaming blade 6 and the straightening blade 7 are both welded with a tungsten carbide layer, which can increase the wear resistance of the blade and encase the PDC cutting teeth 5 to reduce the probability of the PDC cutting teeth 5 falling off. In specific settings, the height of the PDC cutting teeth 5 can be set to 5mm, which can ensure that the PDC cutting teeth 5 can cut the well wall without causing the problem of easy chipping of the tooth edge due to the tooth edge being too high.

[0034] As another implementation of this embodiment, the reaming blade 6 and the straightening blade 7 are both provided with a gauge plate 4. The gauge plate 4 can be made of cemented carbide with a columnar structure, and its height is approximately equal to the height of the PDC cutting tooth 5, and is used to prevent the reaming blade 6 and the straightening blade 7 from directly contacting the well wall and being worn when the PDC cutting tooth 5 breaks.

[0035] In addition, when the reaming blade 6 and the straightening blade 7 need to be widened according to the working conditions, shock-absorbing teeth can also be provided on the reaming blade 6 and the straightening blade 7. The shock-absorbing teeth are close to the gauge plate 4 and the height is approximately equal to the height of the gauge plate 4. The gauge plate 4 is protected by the shock-absorbing teeth.

[0036] The borehole stabilization repair tool in this embodiment has a smaller diameter than the drill bit, and can be undersized when entering the well. By setting the blade structure 3 to a micro-eccentric structure, when the tool rotates with the drill, it can expand the wellbore, thereby repairing the micro-steps and micro-doglegs of the well wall while drilling, and there is no need to trip the drill multiple times, thereby improving the drilling efficiency.

[0037] It should be noted that all features disclosed in this specification, or steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any manner.

[0038] In addition, the above specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the utility model, and these solutions also belong to the disclosure scope of the utility model and fall within the protection scope of the utility model. Those skilled in the art should understand that the utility model specification and its drawings are illustrative and do not constitute a limitation of the claims. The protection scope of the utility model is defined by the claims and their equivalents.

Claims

1. A wellbore stabilization repair tool, characterized in that: include: A drill string (1) having a reduced diameter section (2) disposed thereon; the reduced diameter section (2) is coaxial with the drill string (1), and the outer diameter of the reduced diameter section (2) is smaller than the outer diameter of the drill string (1); Two blade structures (3) are arranged on the surface of the reduced diameter section (2); the two blade structures (3) are arranged at intervals along the axial direction of the drill string (1) and are symmetrically arranged in the radial direction of the drill string (1); The blade structure (3) comprises at least one reaming blade (6) and at least one straightening blade (7) which are uniformly arranged in sequence on the reduced diameter section (2) in the circumferential direction; the height of the straightening blade (7) is less than the height of the reaming blade (6), and the height of the straightening blade (7) and the height of the reaming blade (6) on one blade structure (3) are gradually reduced in a direction away from the other blade structure (3) to form an inclined surface, and a plurality of PDC cutting teeth (5) are welded on the inclined surface at intervals along the extension direction of the inclined surface; the straightening blade (7) and the reaming blade (6) at least partially protrude from the outer surface of the drill string (1), and the extension line of the outer surface of the drill string (1) can fall on one of the PDC cutting teeth (5).

2. The wellbore stabilization repair tool according to claim 1, characterized in that: The surfaces of the hole-expanding blade (6) and the straightening blade (7) are both built-up with a tungsten carbide layer, and the tungsten carbide layer encases the welding position of the PDC cutting tooth (5).

3. The wellbore stabilization repair tool according to claim 2, characterized in that: The PDC cutting teeth (5) have a cutting edge height of 5 mm.

4. The wellbore stabilization repair tool according to claim 3, characterized in that: The hole-expanding blade (6) and the straightening blade (7) both extend in a spiral shape.

5. The wellbore stabilization repair tool according to claim 4, characterized in that: The spiral angles of the hole-expanding blade (6) and the straightening blade (7) are both 8°.

6. The wellbore stabilization repair tool according to claim 5, characterized in that: The expanding blade (6) and the straightening blade (7) are both provided with a gauge plate (4).

7. The wellbore stabilization repair tool according to claim 6, characterized in that: The reaming blade (6) and the straightening blade (7) are both provided with shock absorbing teeth, and the shock absorbing teeth are close to the gauge plate (4).

Images