Intelligent adaptive vertical drilling system and drilling method suitable for high-temperature complex geological environment

Abstract

The application discloses a kind of intelligent adaptation vertical drilling system and drilling method suitable for high temperature complex geological environment, belong to drilling engineering technical field, including upper drilling tool, centralizer, short drill collar, power drilling tool, intelligent adaptation vertical drilling tool, drill bit;Intelligent adaptation vertical drilling tool includes shell, mandrel, annular space is set between the outer wall surface of upper mandrel and the inner wall surface of shell, an even number of counterweights are arranged in annular space, sliding fit between counterweight and mandrel;Drill bit includes drill bit sub, drill bit crown, a plurality of blades are provided on drill bit crown, a plurality of anti-inclination cutting teeth are arranged on the side of the blade, a plurality of drilling cutting teeth are arranged on the bottom of the blade;Supporting block is slidably connected with the blade in radial direction, spring is arranged between supporting block and corresponding blade.The application realizes joint anti-inclination by centrifugal force of counterweight, gravity and the eccentric connection of drill bit, and improves the effect of anti-inclination and straightening.

Description

Technical Field

[0001] This invention belongs to the field of drilling engineering technology, specifically relating to an intelligent adaptive vertical drilling system and drilling method suitable for high-temperature and complex geological environments. Background Technology

[0002] In the drilling field, existing methods for preventing deviation and straightening mainly rely on conventional anti-deviation and straightening drill string assemblies and automated vertical drilling systems. Conventional anti-deviation and straightening drill string assemblies mainly include tower drill strings, pendulum drill strings, full-hole drill strings, off-axis drill strings, and off-center double-center helical stabilizer anti-deviation drill strings, etc. These drill strings are also known as "passive anti-deviation tools." Field application results show that the deflection reduction capacity of these drill strings is difficult to meet the requirements of deep wells, complex wells, and steep structures and steeply inclined formations. Furthermore, it requires sacrificing drilling pressure, which seriously hinders the improvement of drilling speed. Therefore, automated vertical drilling systems have been widely adopted. The most common automated vertical drilling system currently is the push-type automated vertical drilling system. While the push-type system offers significantly improved wellbore deviation control compared to conventional anti-deviation and straightening drill string combinations, it still suffers from the following problems: the high-temperature environment at the bottom of the well makes electronic components in the automated vertical drilling system prone to damage, rendering it unsuitable for ultra-deep wells; its anti-deviation and straightening effect is not ideal in wells with easily enlarged diameters, ultra-large diameters, or ultra-small diameters, and is difficult to further improve; during the deflection reduction process, the push-type automated vertical drilling system applies a pushing force to the upper wellbore wall due to the push ribs, which can easily cause wellbore collapse and stuck drill in unstable formations. Developing a vertical drilling system suitable for high-temperature and complex environments with superior anti-deviation and straightening effects is of great significance.

[0003] Based on the above problems, this invention proposes an intelligent adaptive vertical drilling system and drilling method suitable for high-temperature and complex geological environments. Through a purely mechanical structure, it avoids the defects of existing automatic vertical drilling systems where electronic components are easily damaged at high temperatures. By using the centrifugal force and gravity of the counterweight and the off-axis connection of the drill bit, it achieves a multi-faceted anti-deviation mechanism that utilizes pendulum force, synergistic centrifugal force, integrated oscillation force, and enhanced drill bit cutting ability, thereby improving the anti-deviation and straightening effect. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The intelligent adaptive vertical drilling system, suitable for high-temperature and complex geological environments, includes, in sequence from top to bottom along the axial direction, the upper drilling tool, centralizer, short drill collar, power drilling tool, intelligent adaptive vertical drilling tool, and drill bit;

[0007] The intelligent adaptive vertical drilling tool includes a housing and a mandrel coaxially rotatably fitted inside the housing. The upper end of the housing is connected to the stator of the power drill bit, and the upper end of the mandrel is connected to the rotor of the power drill bit. An annular space is provided between the upper outer wall of the mandrel and the inner wall of the housing. An even number of counterweights are evenly arranged along the circumference in the annular space. The counterweights and the mandrel are slidably fitted along the radial direction of the mandrel.

[0008] The drill bit includes a drill bit connector and a drill bit crown that are coaxially fixedly connected from top to bottom. The upper end of the drill bit connector is fixedly connected to the lower end of the mandrel off-axis. Several blades are evenly arranged along the circumferential direction on the drill bit crown. Several anti-skew cutting teeth are arranged axially on the side diameter protection surface of the blades. Several drilling cutting teeth are arranged at the bottom of the blades. A support block is slidably fitted on the blades radially. A spring is provided between the support block and the corresponding blade. In the same blade, along the rotation direction of the drill bit, the anti-skew cutting teeth are located behind the support block.

[0009] Preferably, the outer casing includes an upper connector, a housing, and a drill bit housing that are sequentially fixedly connected from top to bottom along the axial direction;

[0010] The upper connector is connected to the stator of the power drill bit, and the drill bit connector is connected to the mandrel after being inserted into the drill bit housing.

[0011] Preferably, the spindle and the housing are rotated together by a plurality of bearings arranged along the axial direction.

[0012] Preferably, two bearings are provided, both of which are located in the lower part of the annular space.

[0013] Preferably, a plurality of counterweight grooves corresponding one-to-one with the counterweight blocks are evenly arranged along the circumferential direction on the side wall of the mandrel facing the annular space.

[0014] The counterweight includes a counterweight slider that slides in conjunction with a counterweight groove;

[0015] During the centrifugal motion of the counterweight block along the counterweight slide groove, the counterweight slider does not detach from the corresponding counterweight slide groove.

[0016] Preferably, the counterweight has a convex shape, the upper part of the convex shape is a counterweight slider, and the bottom edge of the convex shape is an arc shape that matches the inner surface of the outer shell.

[0017] Preferably, a layer of lubricating oil is coated on the inner surface of the outer casing facing the annular space.

[0018] Preferably, the blade is provided with a radially extending support groove;

[0019] The support block includes a support slider that slides in conjunction with the support groove. The radially outer end of the support slider is bent vertically away from the corresponding anti-skew cutting teeth to form an L-shaped structure.

[0020] Preferably, a baffle is provided at one radially inner end of the support slider, and a stop block adapted to the baffle is provided at one outer end of the support groove.

[0021] This invention also provides an intelligent adaptive vertical drilling method suitable for high-temperature and complex geological environments.

[0022] An intelligent adaptive vertical drilling method suitable for high-temperature and complex geological environments is implemented using an intelligent adaptive vertical drilling system suitable for such environments. The drilling method is as follows:

[0023] After the power drill is started, it drives the mandrel and drill bit to rotate at high speed. Each counterweight moves radially outward while rotating with the mandrel. After the operation is stable, each counterweight contacts the inner side of the outer shell. The drill bit is connected to the mandrel off-axis, so that the drill bit rotates around the central axis of the mandrel to cut the rock while revolving around the central axis of the well.

[0024] When there is no well deviation during drilling, the lateral cutting ability of each anti-deviation cutting tooth of the drill bit is the same, and the drilling trend is not changed.

[0025] When well deviation exists during drilling, the centrifugal motion of the counterweight and the off-axis connection of the drill bit, combined with the pendulum effect, achieve a joint anti-deviation mechanism.

[0026] The anti-deviation effect of the centrifugal motion of the counterweights: All counterweights are tilted towards the lower side of the wellbore. In the plane formed by the tilt direction and the central axis of the vertical drilling system, the resultant force of the counterweights that rotate to the lower side of the wellbore pressing against the vertical drilling system is greater than that of the counterweights that rotate to the higher side of the wellbore pressing against the vertical drilling system. This provides a lateral force to the drill bit pointing towards the lower side of the wellbore. Under the action of the lateral force, the drill bit presses against the well wall at the lower side of the wellbore. The support block is compressed, and the height of the anti-deviation cutting teeth protruding from the outer side of the support block increases, thereby enhancing the lateral cutting ability of the drill bit pointing towards the lower side of the wellbore.

[0027] The anti-deviation function of the off-axis connection of the drill bit: The gravity of the entire vertical drilling system will cause the drill bit to press against the lower edge of the wellbore, enhancing the lateral cutting ability of the drill bit in the direction of the lower edge of the wellbore; At the same time, as the cutter blade on the side with a larger distance from the center axis of the mandrel rotates to the lower edge of the wellbore, it will rotate and impact the lower edge of the wellbore, increasing the degree of compression of the support block and increasing the height of the anti-deviation cutting teeth protruding from the outer side of the support block, further enhancing the lateral cutting ability of the drill bit in the direction of the lower edge of the wellbore.

[0028] The beneficial effects of this invention are:

[0029] This invention, through a purely mechanical design, avoids the defects of existing automatic vertical drilling systems where electronic components are easily damaged at high temperatures. By using a counterweight on the mandrel and the anti-deviation cutting teeth on the drill bit, combined with the centralizer and the off-axis connection of the drill bit, it achieves a multi-faceted anti-deviation effect by utilizing pendulum force, the centrifugal force of the counterweight, the oscillation force of the drill bit connection, and the enhanced cutting ability of the drill bit, thus improving the anti-deviation and straightening effect. Since the vertical drilling system of this application does not rely on the pusher ribs to apply a pushing force to the upper well wall to achieve the anti-deviation value, it reduces the probability of well wall collapse and stuck drill accidents caused by existing pusher-type automatic vertical drilling systems during deflection. Attached Figure Description

[0030] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0031] Figure 1 This is a schematic diagram of the intelligent adaptive vertical drilling system of the present invention, which is applicable to high-temperature and complex geological environments;

[0032] Figure 2 This is a schematic diagram of the structure of the intelligent adaptive vertical drilling tool in this invention;

[0033] Figure 3 yes Figure 2 Sectional view along axis AA;

[0034] Figure 4 This is a schematic diagram of the drill bit structure in this invention;

[0035] Figure 5 yes Figure 4 BB-direction sectional view;

[0036] Figure 6 It is a force diagram of the counterweight block rotating to the lower side of the wellbore and the counterweight block rotating to the higher side of the wellbore within the plane M formed by the inclined direction and the central axis of the vertical drilling system;

[0037] in:

[0038] 1. Top drill string; 2. Centralizer; 3. Short drill collar; 4. Power drill string; 5. Intelligent adaptive vertical drilling tool; 51. Mandrel; 52. Counterweight; 521. Counterweight slider; 53. Counterweight groove; 54. Top connector; 55. Housing; 56. Drill bit housing; 57. Axial bearing; 58. Radial bearing; 6. Drill bit; 61. Drill bit connector; 62. Drill bit crown; 63. Cutting blade; 631. Support groove; 632. Stop; 64. Anti-skew cutting tooth; 65. Drilling cutting tooth; 66. Support block; 661. Baffle; 67. Spring. Detailed Implementation

[0039] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0040] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0041] In this invention, terms such as "upper," "lower," "bottom," and "top" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are merely relational terms determined for the convenience of describing the structural relationship of the various components or elements of this invention, and do not specifically refer to any component or element in this invention, and should not be construed as limiting this invention.

[0042] In this invention, terms such as "connected" and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0044] Example 1:

[0045] like Figures 1-5 As shown, the intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments includes, in order from top to bottom along the axial direction, the upper drilling tool 1, the stabilizer 2, the short drill collar 3, the power drilling tool 4, the intelligent adaptive vertical drilling tool 5, and the drill bit 6.

[0046] The intelligent adaptive vertical drilling tool 5 includes a housing and a spindle 51 coaxially rotatably fitted inside the housing. The upper end of the housing is connected to the stator of the power drill 4, and the upper end of the spindle 51 is connected to the rotor of the power drill 4. An annular space is provided between the upper outer wall of the spindle 51 and the inner wall of the housing. An even number of counterweights 52 are evenly arranged in the annular space along the circumferential direction. The counterweights 52 and the spindle 51 are slidably fitted in the radial direction of the spindle 51. When the spindle 51 rotates, the counterweights 52 rotate with the spindle 51 and simultaneously undergo centrifugal motion in the radial direction.

[0047] The drill bit 6 includes a drill bit connector 61 and a drill bit crown 62, which are coaxially fixedly connected from top to bottom. The upper end of the drill bit connector 61 is fixedly connected to the lower end of the mandrel 51 off-axis, that is, the central axis of the mandrel 51 is parallel to the central axis of the drill bit 6 but not collinear. The distance 'a' between the central axis of the mandrel 51 and the central axis of the drill bit 6 is in the range of 0 < a ≤ D / 4, where D is the outer diameter of the housing 55. Several blades 63 are evenly arranged along the circumferential direction on the drill bit crown 62. Several anti-deviation cutting teeth 64 are arranged axially on the side diameter protection surface of the blades 63. Several drilling cutting teeth 65 are arranged at the bottom of the blades 63. A support block 66 is slidably fitted on the blades 63 in the radial direction. A spring 67 is provided between the support block 66 and the corresponding blade 63. In the same blade 63, along the rotation direction of the drill bit 6, the anti-deviation cutting teeth 64 are located behind the support block 66, so that when the drill bit 6 rotates, the support block 66 contacts the well wall before the anti-deviation cutting teeth 64.

[0048] In this application, the drill bit 6 is off-axis connected to the mandrel 51. When the mandrel 51 drives the drill bit 6 to rotate, the drill bit 6 rotates around the central axis of the mandrel 51 to cut the rock while simultaneously revolving around the central axis of the well, thereby generating an oscillating force and increasing the diameter of the well.

[0049] When well deviation occurs during drilling, on the one hand, the gravity of the entire vertical drilling system causes it to press against the lower edge of the wellbore, which in turn causes the drill bit 6 to press against the wellbore wall at the lower edge of the wellbore. The support block 66 is compressed, and the height of the anti-deviation cutting teeth 64 protruding from the outer side of the support block 66 increases, enhancing the lateral cutting ability of the drill bit 6 in the direction of the lower edge of the wellbore, thus playing the role of preventing deviation and straightening the well. On the other hand, as the cutter blade 63 on the side with the larger distance from the central axis of the mandrel 51 rotates to the lower edge of the wellbore, the oscillation force generated by the revolution of the drill bit 6 rotates and impacts the lower edge of the wellbore. The degree of compression of the support block 66 increases, and the height of the anti-deviation cutting teeth 64 protruding from the outer side of the support block 66 increases, further enhancing the lateral cutting ability of the drill bit 6 in the direction of the lower edge of the wellbore, thus playing the role of preventing deviation and straightening the well.

[0050] In addition, during drilling, the centralizer 2 forms a fulcrum on the well wall, suspending the lower drill string in the air. The lower drill string then forms a pendulum, generating a pendulum force. Under the action of the pendulum force, the centrifugal force of the counterweight 52, and the oscillation force set by the off-axis setting of the drill bit 6, the drill bit cuts the lower well wall, improving the anti-deviation and straightening effect.

[0051] Preferably, the outer casing includes an upper connector 54, a housing 55, and a drill bit housing 56 that are sequentially fixed from top to bottom along the axial direction, wherein the upper connector 54, the housing 55, and the drill bit housing 56 are threaded together.

[0052] The upper connector 54 is connected to the stator of the power drill 4, and the drill bit connector 61 is connected to the mandrel 51 after being inserted into the drill bit housing 56.

[0053] Preferably, the spindle 51 and the housing 55 are rotated together by a plurality of bearings arranged along the axial direction.

[0054] Preferably, two bearings are provided, both of which are located in the lower part of the annular space. The bearing located in the upper part is an axial bearing 57, and the bearing located in the lower part is a radial bearing 58.

[0055] Preferably, a plurality of counterweight grooves 53 corresponding one-to-one with the counterweight blocks 52 are evenly arranged along the circumferential direction on the side wall of the mandrel 51 facing the annular space.

[0056] The counterweight block 52 includes a counterweight slider 521 that slides in conjunction with the counterweight groove 53;

[0057] During the centrifugal motion of the counterweight block 52 along the counterweight slide 53, the counterweight slider 521 does not detach from the corresponding counterweight slide 53.

[0058] Preferably, the counterweight 52 has a convex shape, the upper part of the convex shape of the counterweight 52 is a counterweight slider 521, and the bottom edge of the convex shape of the counterweight 52 has an arc shape that matches the inner surface of the outer shell.

[0059] Preferably, a layer of lubricating oil is coated on the inner surface of the outer shell facing the annular space to reduce the friction of the counterweight 52 as it rotates with the spindle 51.

[0060] Preferably, the blade 63 is provided with a radially extending support groove 631;

[0061] The support block 66 includes a support slider that slides in conjunction with the support groove 631. The radially outer end of the support slider is bent vertically away from the corresponding anti-skew cutting tooth 64 to form an L-shaped structure.

[0062] Preferably, a baffle 661 is provided at one radially inner end of the support slider, and a stop block 632 adapted to the baffle 661 is provided at one outer end of the support groove 631 to prevent the support slider from slipping out of the support groove 631.

[0063] Example 2:

[0064] An intelligent adaptive vertical drilling method suitable for high-temperature and complex geological environments is implemented using the intelligent adaptive vertical drilling system for high-temperature and complex geological environments described in Example 1. The drilling method is as follows:

[0065] After the power drill bit 4 is started, it drives the mandrel 51 and drill bit 6 to rotate at high speed. Each counterweight 52 rotates with the mandrel 51 and moves outward in a centrifugal motion. After the operation is stable, each counterweight 52 contacts the inner side of the outer shell. The drill bit 6 is connected to the mandrel 51 on the off-axis, so that the drill bit 6 rotates around the central axis of the mandrel 51 to cut the rock while revolving around the central axis of the well.

[0066] When drilling into the well without deviation, each counterweight 52 is horizontally positioned and at the same distance from the central axis of the mandrel 51. The force exerted by each counterweight 52 on the vertical drilling system in a direction perpendicular to the central axis of the mandrel 51 is the centrifugal force generated by its rotation. The centrifugal force of each counterweight 52 is the same, thus providing a uniform circumferential force to the drill bit 6. The lateral cutting ability of each anti-deviation cutting tooth 64 of the drill bit 6 is the same, without changing the drilling trend.

[0067] When well deviation exists during drilling, the centrifugal motion of the counterweight 52, combined with the pendulum action of the off-axis connection of the drill bit 6, achieves joint anti-deviation.

[0068] The anti-deviation effect of the centrifugal motion of the counterweight 52: All counterweights 52 are inclined towards the lower edge of the wellbore. The force exerted by each counterweight 52 on the vertical drilling system in the direction perpendicular to the central axis of the mandrel 51 includes two parts: one part is the centrifugal force generated by its rotation, and the other part is the component of the gravity of each counterweight 52. In the plane formed by the inclination direction and the central axis of the vertical drilling system, the resultant force of the counterweights 52 that rotate to the lower edge of the wellbore pressing against the vertical drilling system is greater than the resultant force of the counterweights 52 that rotate to the higher edge of the wellbore pressing against the vertical drilling system. This provides a lateral force to the drill bit 6 pointing towards the lower edge of the wellbore. Under the action of the lateral force, the drill bit 6 presses against the well wall at the lower edge of the wellbore, the support block 66 is compressed, and the height of the anti-deviation cutting teeth 64 protruding from the outer side of the support block 66 increases, thereby enhancing the lateral cutting ability of the drill bit 6 pointing towards the lower edge of the wellbore.

[0069] The anti-deviation function of the off-axis connection of drill bit 6: The gravity of the entire vertical drilling system causes drill bit 6 to press against the lower edge of the wellbore, enhancing the lateral cutting ability of drill bit 6 in the direction of the lower edge of the wellbore; simultaneously, as the cutter blade 63 on the side with the larger distance from the central axis of mandrel 51 rotates to the lower edge of the wellbore, it exerts a rotational impact on the lower edge of the wellbore, increasing the compression degree of support block 66 and increasing the height of anti-deviation cutting teeth 64 protruding from the outer side of support block 66, further enhancing the lateral cutting ability of drill bit 6 in the direction of the lower edge of the wellbore. Among these, the anti-deviation and straightening effect of the centrifugal motion of counterweight 52, such as... Figure 6 As shown, in plane M formed by the inclined direction and the central axis of the vertical drilling system, the force exerted by the counterweight 52, which rotates to the lower side of the wellbore and is perpendicular to the central axis of the mandrel 51, is F1; the force exerted by the counterweight 522, which rotates to the higher side of the wellbore and is perpendicular to the central axis of the mandrel 51, is F2. Then:

[0070] F1 = F N1 +G sinθ (1)

[0071] F2 = F N2 -G sinθ (2)

[0072] F N1 =mw 2 r1 (3)

[0073] F N2 =mw 2 r2 (4)

[0074] In the formula, F N1 For the centrifugal force of the counterweight 52 rotating to the lower edge of the wellbore, F N2 G is the centrifugal force of the counterweight 52 rotating to the high side of the wellbore, θ is the well inclination angle, m is the weight of the counterweight 52, w is the rotational angular velocity of the mandrel 51, r1 is the centrifugal equivalent radius of the counterweight 52 rotating to the low side of the wellbore, and r2 is the centrifugal equivalent radius of the counterweight 52 rotating to the high side of the wellbore.

[0075] When the counterweight 52 rotates to the bottom edge of the wellbore, under the action of centrifugal force and gravity, it will inevitably move centrifugally to press against the inner side of the outer shell. That is, r1 is the maximum equivalent radius of the counterweight 52 during the rotation of the mandrel 51. Since the counterweight 52 rotates to the bottom edge of the wellbore and presses against the outer shell, the magnitude of the resultant force of the counterweight 52 rotating to the bottom edge of the wellbore pressing against the vertical drilling system is the value of F1.

[0076] When the counterweight 52 rotates to the high edge of the wellbore, there are three possible scenarios:

[0077] First, when G sinθ > mw 2 When r1, under the action of the gravitational component, it cannot perform centrifugal action relative to the mandrel 51 and contact the inner side of the outer shell. Therefore, it cannot provide a force pressing against the outer shell. At this time, the resultant force of the counterweight block 52 rotating to the high side of the wellbore pressing against the vertical drilling system is 0.

[0078] In this case, within the plane M formed by the inclined direction and the central axis of the vertical drilling system, the lateral force provided by the counterweight 52 to the drill bit 6, pointing towards the lower edge of the wellbore, is the magnitude of F1.

[0079] Second, when G sinθ=mw 2 When r1, under the action of the gravitational component, it moves centrifugally to contact the inner side of the outer shell, but cannot provide a force to press against the outer shell. At this time, the resultant force of the counterweight 52 rotating to the high side of the wellbore pressing against the vertical drilling system is 0.

[0080] In this case, within the plane M formed by the inclined direction and the central axis of the vertical drilling system, the lateral force provided by the counterweight 52 to the drill bit 6, pointing towards the lower edge of the wellbore, is the magnitude of F1.

[0081] Third, when G sinθ < mw 2 When r1, under the action of centrifugal force, it moves centrifugally to press against the inner side of the outer shell, so that the resultant force of the counterweight block 52, which rotates to the high side of the wellbore, presses against the vertical drilling system is the value of F2, and r2=r1;

[0082] In this case, within the plane M formed by the inclined direction and the central axis of the vertical drilling system, the lateral force provided by the counterweight 52 to the drill bit 6, pointing towards the lower edge of the wellbore, is the difference between F1 and F2, which is 2G sinθ.

[0083] This invention, through a purely mechanical design, avoids the drawback of existing automatic vertical drilling systems where electronic components are easily damaged at high temperatures. By incorporating the counterweight 52 on the mandrel and the anti-deviation cutting teeth on the drill bit, combined with the off-axis connection of the stabilizer 2 and the drill bit 6, this invention achieves a multi-faceted anti-deviation effect, utilizing pendulum force, the centrifugal force of the counterweight 52, the oscillating force of the drill bit 6's connection, and enhanced cutting capability of the drill bit 6. This improves the anti-deviation and straightening performance. The technique of the stabilizer 2 forming a fulcrum to induce a pendulum effect in the lower drill string for anti-deviation and straightening is existing technology and its implementation principle will not be elaborated here.

[0084] In addition, since the vertical drilling system of this application does not rely on the pusher ribs to apply a pushing force to the upper well wall to achieve anti-deviation and straight drilling, it reduces the probability of well wall collapse and stuck drill accidents caused by existing pusher-type automatic vertical drilling systems during deflection.

[0085] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, they are not intended to limit the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. An intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments, comprising, in sequence from top to bottom along the axial direction, an upper drilling tool, a centralizer, a short drill collar, a power drilling tool, an intelligent adaptive vertical drilling tool, and a drill bit; characterized in that, The intelligent adaptive vertical drilling tool includes a housing and a mandrel coaxially rotatably fitted inside the housing. The upper end of the housing is connected to the stator of the power drill bit, and the upper end of the mandrel is connected to the rotor of the power drill bit. An annular space is provided between the upper outer wall of the mandrel and the inner wall of the housing. An even number of counterweights are evenly arranged in the annular space along the circumferential direction. The counterweights and the mandrel slide in a radial fit along the mandrel 51. The drill bit includes a drill bit connector and a drill bit crown that are coaxially fixedly connected from top to bottom. The upper end of the drill bit connector is fixedly connected to the lower end of the mandrel off-axis. Several blades are evenly arranged along the circumferential direction on the drill bit crown. Several anti-skew cutting teeth are arranged axially on the side diameter protection surface of the blades. Several drilling cutting teeth are arranged at the bottom of the blades. A support block is slidably fitted on the blades radially. A spring is provided between the support block and the corresponding blade. In the same blade, along the rotation direction of the drill bit, the anti-skew cutting teeth are located behind the support block.

2. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 1, characterized in that, The outer casing includes an upper connector, a housing, and a drill bit housing, which are fixedly connected sequentially from top to bottom along the axial direction. The upper connector is connected to the stator of the power drill bit, and the drill bit connector is connected to the mandrel after being inserted into the drill bit housing.

3. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 2, characterized in that, The spindle and the housing are rotated together by a number of bearings arranged along the axial direction.

4. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 3, characterized in that, Two bearings are provided, both located in the lower part of the annular space.

5. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 1, characterized in that, Several counterweight grooves, each corresponding to a counterweight block, are evenly arranged along the circumference on the side wall of the mandrel facing the annular space. The counterweight includes a counterweight slider that slides in conjunction with a counterweight groove; During the centrifugal motion of the counterweight block along the counterweight slide groove, the counterweight slider does not detach from the corresponding counterweight slide groove.

6. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 1, characterized in that, The counterweight has a convex shape, the upper part of which is a counterweight slider, and the bottom edge of which is an arc shape that matches the inner surface of the outer shell.

7. The intelligent adaptive vertical drilling system suitable for high-temperature and complex geological environments as described in claim 1, characterized in that, A layer of lubricating oil is applied to the inner surface of the outer shell facing the annular space.

8. The intelligent adaptive vertical drilling system for high-temperature and complex geological environments as described in claim 1, characterized in that, The blade is provided with a radially extending support groove; The support block includes a support slider that slides in conjunction with the support groove. The radially outer end of the support slider is bent vertically away from the corresponding anti-skew cutting teeth to form an L-shaped structure.

9. The intelligent adaptive vertical drilling system for high-temperature and complex geological environments as described in claim 8, characterized in that, A baffle is provided at one radially inner end of the support slider, and a stop block adapted to the baffle is provided at one outer end of the support groove.

10. A smart adaptive vertical drilling method suitable for high-temperature and complex geological environments, implemented using the smart adaptive vertical drilling system for high-temperature and complex geological environments as described in any one of claims 1 to 9, characterized in that, The drilling method is as follows: After the power drill is started, it drives the mandrel and drill bit to rotate at high speed. Each counterweight moves radially outward while rotating with the mandrel. After the operation is stable, each counterweight contacts the inner side of the outer shell. The drill bit is connected to the mandrel off-axis, so that the drill bit rotates around the central axis of the mandrel to cut the rock while revolving around the central axis of the well. When there is no well deviation during drilling, the lateral cutting ability of each anti-deviation cutting tooth of the drill bit is the same, and the drilling trend is not changed. When well deviation exists during drilling, the centrifugal motion of the counterweight is connected to the off-axis of the drill bit, and combined with the pendulum effect generated by the centralizer, a combined anti-deviation mechanism is achieved. The anti-deviation effect of the centrifugal motion of the counterweights: All counterweights are tilted towards the lower side of the wellbore. In the plane formed by the tilt direction and the central axis of the vertical drilling system, the resultant force of the counterweights that rotate to the lower side of the wellbore pressing against the vertical drilling system is greater than that of the counterweights that rotate to the higher side of the wellbore pressing against the vertical drilling system. This provides a lateral force to the drill bit pointing towards the lower side of the wellbore. Under the action of the lateral force, the drill bit presses against the well wall at the lower side of the wellbore. The support block is compressed, and the height of the anti-deviation cutting teeth protruding from the outer side of the support block increases, thereby enhancing the lateral cutting ability of the drill bit pointing towards the lower side of the wellbore. The anti-deviation function of the off-axis connection of the drill bit: The gravity of the entire vertical drilling system will cause the drill bit to press against the lower edge of the wellbore, enhancing the lateral cutting ability of the drill bit in the direction of the lower edge of the wellbore; At the same time, as the cutter blade on the side with a larger distance from the center axis of the mandrel rotates to the lower edge of the wellbore, it will rotate and impact the lower edge of the wellbore, increasing the degree of compression of the support block and increasing the height of the anti-deviation cutting teeth protruding from the outer side of the support block, further enhancing the lateral cutting ability of the drill bit in the direction of the lower edge of the wellbore.

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