How to use high-speed balanced PDC drill bits for oil drilling

Abstract

The invention discloses a method for using a high-speed balanced PDC drill bit for oil drilling. The technical scheme is as follows: the lower end of the upper joint is connected to the center drill bit through a butt joint, and the boring drill bit body is connected by a boring and milling transmission sleeve; multiple groups of milling drill bit bodies are arranged in the cavity between the boring drill bit body and the center drill bit, and a speed transmission intermediate wheel is arranged on the outer wall of each milling drill bit body, which is meshed with the teeth of the outer wall of the butt joint and the teeth of the inner wall of the boring and milling transmission sleeve through the speed transmission intermediate wheel; the milling drill bit body is provided with a speed transmission bearing and a speed transmission pressure cap, and a graded bearing is arranged between the boring and milling transmission sleeve and the upper joint; the beneficial effect is that the center drill bit of the invention can drill downward, the milling drill bit body can realize the rotary drilling function of self-rotation and revolution around the center drill bit, the boring drill bit body rotates around the center drill bit, the rotation speed of the boring drill bit body is reduced, the drill burning phenomenon at the outer diameter part is reduced, and the service life of the drill bit is increased.

Description

Technical Field

[0001] The invention relates to the technical field of oil drilling, in particular to a method for using a high-speed balanced PDC drill bit for oil drilling. Background Art

[0002] In the process of oil extraction, drilling is an important link. In the current drilling process, improving the performance of drilling tools is the direction that all drilling tool companies have been working hard on. The existing drill bit is one of the important tools for oil drilling. Whether the drill bit is adapted to the nature of the rock and its quality plays a very important role in the selection of drilling technology, especially in terms of drilling quality, drilling speed and drilling cost. PDC drill bits are a kind of rock breaking tool widely used in the oil and gas exploration and development industry today. It effectively improves mechanical drilling tools and shortens the drilling cycle. PDC drill bits mainly have four components, namely diamond composite pieces, nozzles, matrix bodies and drill bit bodies. The existing problems are: during drilling, PDC drill bits are used to drill the oil and gas wells, and the drill bits are used to drill the wells. The dc drill bit is lowered into the well and rotates under the drive of the drill pipe to achieve drilling. When the diamond composite piece is worn out or damaged, drilling cannot be continued and the drill pipe can only be lifted to replace a new drill bit. When drilling shallow oil wells, the time for replacing the drill bit is relatively short and acceptable. However, when drilling a deep well of several thousand meters, when the drill bit needs to be replaced, the drill pipes need to be lifted up one by one. The general length of the existing drill pipes is about 7-13 meters. A well depth of 5,000 meters requires about 500 drill pipes. Such lifting and lowering will cause a lot of time to be wasted on pulling up and down the drill pipe, causing the cost of drilling to rise sharply and forming huge drilling expenses. Therefore, how to improve the service life of the pdc drill bit is of great significance.

[0003] In addition, when the hole diameter to be drilled is larger, a PDC drill bit with a larger diameter is required. However, the larger the diameter, the more problems it brings. The linear speed of rotation at the center position of the lower end of the drill bit is very different from the linear speed of the outer diameter of the drill bit. In other words, the angular velocity of rotation at the center position and the outer diameter position is the same under the drive of the drill pipe, but the linear speed of rotation is very different. This causes the outer diameter of the large-diameter drill bit to quickly burn out, reducing the hardness of the drill bit, causing the drill bit to quickly lose performance and reduce its service life, so the drill bit can only be replaced frequently, causing the drilling cost to increase exponentially. Summary of the invention

[0004] The purpose of the present invention is to provide a method for using a high-speed balanced PDC drill bit for oil drilling in view of the above-mentioned defects in the prior art. By designing a center drill bit, a milling drill bit body and a boring drill bit body, the center drill bit can drill downward, the milling drill bit body can realize the rotary drilling function of self-rotation and revolution around the center drill bit, and the boring drill bit body rotates around the center drill bit, thereby reducing the rotation speed of the boring drill bit body, reducing the drill burning phenomenon at the outer diameter part, and improving the service life of the drill bit.

[0005] The present invention discloses a method for using a high-speed balanced PDC drill bit for oil drilling, and the technical solution thereof includes the following steps:

[0006] 1. Connect the upper joint to the drill pipe and mud. The drill pipe drives the upper joint to rotate. Driven by the upper joint, the butt joint rotates at the same angular velocity. The lower end of the butt joint is connected to the center drill bit, so the center drill bit is driven to rotate. The lower end of the center drill bit is a conical structure, and the center drill bit is distributed with a center drill carbide cutter head to realize the drilling function of the center drill bit.

[0007] Second, since an outer gear is provided on the outer side of the lower end of the joint, which is used to mesh with the speed transmission intermediate gear on the outer side of each milling drill bit body, and the speed transmission intermediate gear is also meshed with the speed transmission internal gear on the inner wall of the boring and milling transmission sleeve, each milling drill bit body is driven to move along the speed transmission internal gear to form a revolution around the joint while rotating on its own. Because a milling body is provided at the lower end of each milling drill bit body, and milling carbide cutter heads are inlaid and welded in sequence, and a speed transmission bearing is installed at the upper end of the transmission body of the milling drill bit body, the speed transmission bearing forms a downward drilling function under the push of the downward pressure of the first pressure bearing and the second pressure bearing;

[0008] 3. Under the action of the meshing of the speed transmission intermediate wheel and the speed transmission internal gear on the inner wall of the boring and milling transmission sleeve, the boring drill bit body is driven to perform a decelerated rotational motion. The top of the boring and milling transmission sleeve rotates in coordination with the upper joint through the graded bearing and the bearing radial spacer sleeve. The lower outer wall of the boring drill bit body is provided with boring carbide cutter heads that are arranged, inlaid and welded in sequence to realize the function of downhole drilling.

[0009] Preferably, a high-speed balanced PDC drill bit for oil drilling comprises an upper joint, a center drill bit and a butt joint, wherein the lower end of the upper joint is connected to the upper end of the center drill bit through the butt joint, and is characterized in that: it also comprises a graded bearing, a speed transmission cap, a speed transmission bearing, a milling drill bit body, a speed transmission intermediate wheel, a boring and milling transmission sleeve and a boring drill bit body, wherein the center drill bit is a cylindrical structure; the boring drill bit body is a cylindrical structure, located at the outermost circle of the center drill bit, and the upper end of the boring drill bit body is driven and connected through the boring and milling transmission sleeve; a plurality of groups of milling drill bit bodies are arranged in the cavity between the boring drill bit body and the center drill bit, and a transmission gear is arranged on the outer wall of each milling drill bit body The speed transmission intermediate wheel is meshed with the teeth on the outer wall of the butt joint and the teeth on the inner wall of the boring and milling transmission sleeve through the speed transmission intermediate wheel; a speed transmission bearing and a speed transmission pressure cap are arranged on the top of each milling drill bit body, a stepped bearing is arranged between the upper end of the boring and milling transmission sleeve and the upper joint, and a bearing pressure cap is arranged on the upper part of the stepped bearing; the upper joint drives the butt joint to rotate, and the butt joint drives multiple milling drill bit bodies to rotate, the milling drill bit body forms a movement of self-rotation and revolution around the center drill bit, and the boring drill bit body performs a rotational movement driven by the boring and milling transmission sleeve; multiple polycrystalline diamond composite cutter heads are sequentially inlaid and welded in the inner walls of the milling drill bit body, the boring drill bit body and the center drill bit.

[0010] Preferably, the above-mentioned center drill bit includes a drill body, a chip removal spiral groove, a center circulation hole, a bit embedding hole, an upper connecting external thread, a water outlet hole and a center drill carbide bit. The bottom of the drill body is a conical structure, the upper end is provided with an upper connecting external thread, a chip removal spiral groove is provided on the outside of the drill body, a center circulation hole is provided in the center of the drill body, and multiple water outlet holes are connected; multiple inclined bit embedding holes are sequentially provided in the drill body, and a center drill carbide bit is embedded and welded in the bit embedding hole.

[0011] Preferably, the above-mentioned milling drill bit body includes a milling body and a transmission body, the milling body is a cylindrical structure, and milling carbide cutter heads are inlaid and welded in sequence; the upper part of the milling body is the transmission body, the outer diameter of the transmission body is smaller than the outer diameter of the milling body, and a groove is provided in the middle part of the transmission body, and a torque key is provided in the groove, and the speed transmission intermediate wheel is connected through the torque key; a speed transmission bearing is installed at the upper end of the transmission body, and a speed transmission pressure cap is installed above the speed transmission bearing through a thread.

[0012] Preferably, the top of the boring drill body is provided with an internal thread, the lower part of the boring drill body is cylindrical, and inclined holes are distributed in sequence on the cylinder, and a boring carbide cutter head is embedded and welded in each inclined hole; the top of the boring drill body is connected to the boring and milling transmission sleeve through an internal thread.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] 1. The present invention designs a center drill bit, a milling drill bit body and a boring drill bit body. The center drill bit can rotate downward to achieve drilling. Multiple milling drill bit bodies can achieve the drilling functions of self-rotation and revolution around the center drill bit. The boring drill bit body rotates around the center drill bit. Due to the design of the butt joint, the speed transmission intermediate wheel and the boring and milling transmission sleeve, the linear speeds of the three drill bits can be balanced, the revolution speed of the milling drill bit body is reduced, and the rotation speed of the boring drill bit body is also reduced, the situation of drill burning is reduced, the high-speed operation is stable, and the service life of the entire drill bit is extended;

[0015] 2. The milling drill bit body of the present invention simulates the mechanical milling action. The milling drill bit body not only rotates itself but also moves, making circular movements around the annular gap formed by the center drill bit and the cylindrical boring drill bit body. In this way, the drilling efficiency of the entire drill bit is improved and the drill sticking is reduced. The cylindrical boring drill bit body only makes circular movements and has a welded boring carbide cutter head embedded on itself, simulating the boring action and improving the drilling efficiency of large-hole wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front structural schematic diagram of the present invention;

[0017] Figure 2 yes Figure 1 AA cross-section diagram of ;

[0018] Figure 3 It is a schematic diagram of the structure of the center drill bit;

[0019] Figure 4 It is a schematic diagram of the structure of the milling drill bit body;

[0020] Figure 5 It is a structural schematic diagram of the main body of the boring drill bit;

[0021] Figure 6 It is a structural schematic diagram of a boring and milling transfer sleeve;

[0022] Figure 7 yes Figure 6 A schematic cross-sectional view of BB;

[0023] Figure 8 It is a structural diagram of the butt joint;

[0024] Fig. 9 It is a schematic diagram of the CC structure of the butt joint;

[0025] In the above figure: upper joint 1, bearing pressure cap 2, connecting screw 3, bearing radial spacer sleeve 4, graded bearing 5, first pressure bearing 6, second pressure bearing 7, speed transmission cap 8, speed transmission bearing 9, milling drill body 10, milling carbide cutter head 11, speed transmission intermediate wheel 12, boring and milling transmission sleeve 13, boring drill body 14, boring carbide cutter head 15, center drill head 16, butt joint 17;

[0026] Milling body 10.1, transmission body 10.2, torque key 10.2.1, cylindrical sleeve 13.1, speed transmission internal gear 13.2, lower bearing stand 13.3, upper bearing stand 13.4, torque transmission extension distance 13.5, external thread 13.6, internal thread 14.1, drill body 16.1, chip removal spiral groove 16.2, center circulation hole 16.3, cutter head inlay hole 16.4, upper connection external thread 16.5, water outlet hole 16.6, center drill carbide cutter head 16.7, external gear 17.1, center drill head docking thread 17.2, power docking thread 17.3. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0028] Example 1, reference Figure 1-2 The invention relates to a high-speed balanced PDC drill bit for oil drilling, comprising an upper joint 1, a graded bearing 5, a speed transmission cap 8, a speed transmission bearing 9, a milling drill bit body 10, a speed transmission intermediate wheel 12, a boring and milling transmission sleeve 13, a boring and drill bit body 14, a center drill bit 16 and a butt joint 17. The lower end of the upper joint 1 is connected to the upper end of the center drill bit 16 through the butt joint 17. The center drill bit 16 is a cylindrical structure; the boring and drill bit body 14 is a cylindrical structure, located at the outermost circle of the center drill bit 16, and the upper end of the boring and drill bit body 14 is driven and connected through the boring and milling transmission sleeve 13; a plurality of groups of milling drill bit bodies 10 are arranged in the cavity between the boring and drill bit body 14 and the center drill bit 16, and a speed transmission gear 12 is arranged on the outer wall of each milling drill bit body 10. The intermediate wheel 12 is meshed with the teeth on the outer wall of the docking joint 17 and the teeth on the inner wall of the boring and milling transmission sleeve 13 through the speed transmission intermediate wheel 12; a speed transmission bearing 9 and a speed transmission pressure cap 8 are provided on the top of each milling drill bit body 10, and a graded bearing 5 is provided between the upper end of the boring and milling transmission sleeve 13 and the upper joint 1, and a bearing pressure cap 2 is provided on the upper part of the graded bearing 5; the upper joint 1 drives the docking joint 17 to rotate, and the docking joint 17 drives multiple milling drill bit bodies 10 to rotate, the milling drill bit body 10 forms a movement of self-rotation and revolution around the center drill bit 16, and the boring drill bit body 14 rotates under the drive of the boring and milling transmission sleeve 13; multiple polycrystalline diamond composite cutter heads are sequentially inlaid and welded in the inner walls of the milling drill bit body 10, the boring drill bit body 14 and the center drill bit 16.

[0029] Reference Figure 3 The center drill bit 16 of the present invention comprises a drill body 16.1, a chip removal spiral groove 16.2, a center circulation hole 16.3, a cutter head embedding hole 16.4, an upper connecting external thread 16.5, a water outlet hole 16.6 and a center drill carbide cutter head 16.7. The bottom of the drill body 16.1 is a conical structure, and an upper connecting external thread 16.5 is provided at the upper end. A chip removal spiral groove 16.2 is provided on the outer side of the drill body 16.1 to facilitate the discharge of crushed stone chips. A center circulation hole 16.3 is provided in the center of the drill body 16.1, and multiple water outlet holes 16.6 are connected to connect drilling mud during drilling; multiple inclined cutter head embedding holes 16.4 are sequentially provided in the drill body 16.1, and a welded center drill carbide cutter head 16.7 is embedded in the cutter head embedding hole 16.4.

[0030] Reference Figure 4 The milling drill bit body 10 of the present invention comprises a milling body 10.1 and a transmission body 10.2, wherein the milling body 10.1 is a cylindrical structure and is sequentially inlaid with and welded with milling carbide cutter heads 11; the upper part of the milling body 10.1 is the transmission body 10.2, the outer diameter of the transmission body 10.2 is smaller than the outer diameter of the milling body 10.1, and a groove is provided in the middle part of the transmission body 10.2, a torque key 10.2.1 is provided in the groove, and a speed transmission intermediate wheel 12 is connected through the torque key 10.2.1; a speed transmission bearing 9 is installed at the upper end of the transmission body 10.2, and a speed transmission pressure cap 8 is installed above the speed transmission bearing 9 through a thread.

[0031] Reference Figure 5 The top of the boring drill body 14 of the present invention is provided with an internal thread 14.1, the lower part of the boring drill body 14 is cylindrical, and inclined holes are distributed in sequence on the cylinder, and a boring carbide cutter head 15 is embedded and welded in each inclined hole; the top of the boring drill body 14 is connected to the boring and milling transmission sleeve 13 through the internal thread 14.1.

[0032] In addition, the drilling mud can be replaced through the center circulation hole 16.3 and the water outlet hole 16.6 on the center drill bit 16, and the gap formed between the center drill bit 16, the milling drill bit body 10 and the boring drill bit body 14.

[0033] Reference Figure 6-7The boring and milling transmission sleeve 13 of the present invention comprises a cylindrical sleeve body 13.1, a speed transmission internal gear 13.2, a lower bearing platform 13.3, an upper bearing platform 13.4, and a torque transmission extension distance 13.5. The speed transmission internal gear 13.2 is arranged on the inner wall of the bottom of the cylindrical sleeve body 13.1 for meshing with the speed transmission intermediate gear 12, and an external thread 13.6 is arranged on the outer wall; the middle part of the cylindrical sleeve body 13.1 is the torque transmission extension distance 13.5, and the inner wall of the upper end of the cylindrical sleeve body 13.1 is provided with a lower bearing platform 13.3 and an upper bearing platform 13.4, and the inner diameter of the lower bearing platform 13.3 is smaller than the inner diameter of the upper bearing platform 13.4; the lower bearing platform 13.3 is used to install the first pressure bearing 6, the second pressure bearing 7 and the speed transmission bearing 9; the upper bearing platform 13.4 is used to install the graded bearing 5.

[0034] Reference Figure 8-9 The outer side of the lower end of the docking joint 17 of the present invention is provided with an external gear 17.1 for meshing with the speed transmission intermediate wheel 12; the inner wall of the lower end of the docking joint 17 is provided with a center drill bit docking thread 17.2 for connecting with the center drill bit 16; the top of the docking joint 17 is provided with a power docking thread 17.3 for connecting with the lower end of the upper joint 1.

[0035] The above-mentioned speed transmission bearing 9 is installed between the first pressure bearing 6 and the second pressure bearing 7. The first pressure bearing 6 and the second pressure bearing 7 push the speed transmission bearing 9 to form a downward pressure, thereby pushing the milling drill body 10 to drill downward.

[0036] In addition, the outer wall of the upper joint 1 is provided with a bearing radial spacer sleeve 4, the outer wall of the bearing radial spacer sleeve 4 is sleeved with a graded bearing 5, a bearing pressure cap 2 is provided on the upper side of the graded bearing 5, and is fixed to the top of the boring and milling transmission sleeve 13 by a connecting screw 3.

[0037] The method for using the high-speed balanced PDC drill bit for oil drilling mentioned in the present invention comprises the following process:

[0038] 1. Connect the upper joint 1 to the drill pipe and the mud, and the drill pipe drives the upper joint 1 to rotate. Driven by the upper joint 1, the butt joint 17 rotates at the same angular velocity. The lower end of the butt joint 17 is connected to the center drill bit 16, so the center drill bit 16 is driven to rotate. The lower end of the center drill bit 16 is a conical structure, and the center drill bit 16 is distributed with a center drill carbide cutter head 16.7 to realize the drilling function of the center drill bit 16;

[0039] Second, since an outer gear 17.1 is provided on the outer side of the lower end of the docking head 17, which is used to mesh with the speed transmission intermediate gear 12 on the outer side of each milling drill head body 10, and the speed transmission intermediate gear 12 is also meshed with the speed transmission internal gear 13.2 on the inner wall of the boring and milling transmission sleeve 13, each milling drill head body 10 is driven to move along the speed transmission internal gear 13.2 to form a revolution around the docking head 17 while rotating. Because a milling body 10.1 is provided on the lower end of each milling drill head body 10, and a milling carbide cutter head 11 is sequentially inlaid and welded, and a speed transmission bearing 9 is installed on the upper end of the transmission body 10.2 of the milling drill head body 10, the speed transmission bearing 9 forms a downward drilling function under the push of the downward pressure of the first pressure bearing 6 and the second pressure bearing 7;

[0040] 3. Under the action of the meshing of the speed transmission intermediate wheel 12 and the speed transmission internal gear 13.2 on the inner wall of the boring and milling transmission sleeve 13, the boring drill bit body 14 is driven to perform a decelerated rotational motion. The top of the boring and milling transmission sleeve 13 rotates in coordination with the upper joint 1 through the graded bearing 5 and the bearing radial spacing sleeve 4. The lower outer wall of the boring drill bit body 14 is provided with boring carbide cutter heads 15 arranged in sequence and inlaid and welded to realize the function of downhole drilling.

[0041] The above are only some preferred embodiments of the present invention. Any person skilled in the art may modify the above technical solutions or modify them into equivalent technical solutions. Therefore, the corresponding simple modifications or equivalent transformations made according to the technical solutions of the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for using a high-speed balanced PDC drill bit for oil drilling, characterized in that The process includes:

1. The upper joint (1) is connected to the drill rod and the mud fluid, and the drill rod drives the upper joint (1) to rotate. Under the drive of the upper joint (1), the butt joint (17) rotates at the same angular velocity. The lower end of the butt joint (17) is connected to the center drill bit (16), so as to drive the center drill bit (16) to rotate. The lower end of the center drill bit (16) is a conical structure, and the center drill bit (16) is distributed with a center drill carbide cutter head (16.7), so as to realize the drilling function of the center drill bit (16); Second, since an outer gear (17.1) is provided on the outer side of the lower end of the docking joint (17) for meshing with the transmission intermediate gear (12) on the outer side of each milling drill head body (10), and the transmission intermediate gear (12) is also meshed with the transmission internal gear (13.2) on the inner wall of the boring and milling transmission sleeve (13), each milling drill head body (10) is driven to move along the transmission internal gear (13.2) while rotating, thereby forming a revolution around the docking joint (17). Since a milling body (10.1) is provided on the lower end of each milling drill head body (10), and a milling carbide cutter head (11) is sequentially inlaid and welded, and a transmission bearing (9) is installed on the upper end of the transmission body (10.2) of the milling drill head body (10), the transmission bearing (9) forms a downward drilling function under the push of the downward pressure of the first pressure bearing (6) and the second pressure bearing (7); 3. Under the action of the meshing of the speed transmission intermediate wheel (12) and the speed transmission internal gear (13.2) on the inner wall of the boring and milling transmission sleeve (13), the boring drill bit body (14) is driven to perform a rotational motion with a reduced speed. The top of the boring and milling transmission sleeve (13) rotates in coordination with the upper joint (1) through the graded bearing (5) and the bearing radial spacing sleeve (4). The lower outer wall of the boring drill bit body (14) is provided with boring carbide cutter heads (15) arranged in sequence and inlaid and welded, thereby realizing the function of downhole drilling. The center drill bit (16) is a cylindrical structure; the boring drill bit body (14) is a cylindrical structure and is located at the outermost circle of the center drill bit (16); the upper end of the boring drill bit body (14) is driven and connected via a boring and milling transmission sleeve (13); and a plurality of groups of milling drill bit bodies (10) are arranged in the cavity between the boring drill bit body (14) and the center drill bit (16).

2. The method for using a high-speed balanced PDC drill bit for oil drilling according to claim 1, characterized in that: A high-speed balanced PDC drill bit for oil drilling comprises an upper joint (1), a center drill bit (16) and a butt joint (17). The lower end of the upper joint (1) is connected to the upper end of the center drill bit (16) via the butt joint (17). The drill bit is characterized in that it also comprises a graded bearing (5), a speed transmission cap (8), a speed transmission bearing (9), a milling drill bit body (10), a speed transmission intermediate wheel (12), a boring and milling transmission sleeve (13) and a boring and drill bit body (14). The outer wall of each milling drill bit body (10) is provided with a speed transmission intermediate wheel (12), which meshes with the teeth on the outer wall of the butt joint (17) and the teeth on the inner wall of the boring and milling transmission sleeve (13); the top of each milling drill bit body (10) A speed transmission bearing (9) and a speed transmission pressure cap (8) are provided. A stepped bearing (5) is provided between the upper end of the boring and milling transmission sleeve (13) and the upper joint (1). A bearing pressure cap (2) is provided on the upper part of the stepped bearing (5). The upper joint (1) drives the docking joint (17) to rotate. The docking joint (17) drives a plurality of milling drill bit bodies (10) to rotate. The milling drill bit bodies (10) rotate on themselves and around a center drill bit (16). The boring drill bit bodies (14) rotate under the drive of the boring and milling transmission sleeve (13). A plurality of polycrystalline diamond composite cutter heads are sequentially inlaid and welded in the inner walls of the milling drill bit bodies (10), the boring drill bit bodies (14) and the center drill bit (16).

3. The method for using a high-speed balanced PDC drill bit for oil drilling according to claim 1, characterized in that: The center drill bit (16) comprises a drill body (16.1), a chip removal spiral groove (16.2), a center circulation hole (16.3), a cutter head embedding hole (16.4), an upper connecting external thread (16.5), a water outlet hole (16.6) and a center drill carbide cutter head (16.7). The bottom of the drill body (16.1) is a conical structure, the upper end is provided with an upper connecting external thread (16.5), the outer side of the drill body (16.1) is provided with a chip removal spiral groove (16.2), the center of the drill body (16.1) is provided with a center circulation hole (16.3), and the plurality of water outlet holes (16.6) are connected. The drill body (16.1) is provided with a plurality of inclined cutter head embedding holes (16.4) in sequence, and a center drill carbide cutter head (16.7) is embedded and welded in the cutter head embedding hole (16.4).

4. The method for using a high-speed balanced PDC drill bit for oil drilling according to claim 1, characterized in that: The milling drill bit body (10) comprises a milling body (10.1) and a transmission body (10.2); the milling body (10.1) is a cylindrical structure, and is sequentially inlaid with welded milling carbide cutter heads (11); the upper part of the milling body (10.1) is the transmission body (10.2); the outer diameter of the transmission body (10.2) is smaller than the outer diameter of the milling body (10.1), and a groove is provided in the middle of the transmission body (10.2), and a torque key (10.2.1) is provided in the groove, and the speed transmission intermediate wheel (12) is connected via the torque key (10.2.1); a speed transmission bearing (9) is installed at the upper end of the transmission body (10.2), and a speed transmission pressure cap (8) is installed above the speed transmission bearing (9) via a thread.

5. The method for using a high-speed balanced PDC drill bit for oil drilling according to claim 1, characterized in that: The top of the boring drill body (14) is provided with an internal thread (14.1); the lower part of the boring drill body (14) is cylindrical, and inclined holes are sequentially distributed on the cylinder, and a boring carbide cutter head (15) is embedded and welded in each inclined hole; the top of the boring drill body (14) is connected to the boring and milling transmission sleeve (13) via the internal thread (14.1).

Images