Low-vibration high-stability PDC drill bit and drilling tool

Abstract

The application belongs to the field of oil exploration equipment, and discloses a low-vibration and high-stability PDC drill bit, which comprises a drill bit main body, the drill bit main body comprises a plurality of blades arranged in the circumferential direction, each blade has a cone part located on the inner side in the radial direction and a head part located on the outer side in the radial direction, the head part has a crown and a stabilizing part located on the inner side of the crown in the radial direction, and the stabilizing part has a stepped profile with the upper part being convex and the lower part being concave. The low-vibration and high-stability PDC drill bit and drill provided by the application can limit the lateral vibration and whirling of the PDC drill bit, improve the heat dissipation and the removal of cuttings of the drill bit, effectively avoid the tooth collapse and excessive wear of the core part and the inner cone part, and improve the service life of the drill bit by optimizing the profile of the drill bit and adopting the stepped two-section design of the inner head type of the PDC drill bit close to the center.

Description

Technical Field

[0001] This invention relates to the field of petroleum exploration equipment, and more particularly to a low-vibration, high-stability PDC drill bit and a drilling tool having the PDC drill bit. Background Technology

[0002] Polycrystalline diamond composite (PDC) drill bits are a new type of high-efficiency rock breaking tool in the field of drilling engineering technology. When dealing with soft to medium-hard formations, the cutting teeth of PDC drill bits use a shearing method to break rocks, resulting in a significant improvement in drilling efficiency compared to traditional roller cone drill bits. Currently, PDC drill bits have been widely used in oil and gas drilling engineering.

[0003] PDC drill bits primarily consist of a drill bit body and a polycrystalline diamond (PCD) composite cutting edge. During rock fracturing, drill pressure acts on the drill bit, driving it downwards. The self-sharpening, high-hardness, and wear-resistant PCD composite cutting edge acts like a sharp scraping tool, directly scraping the rock to achieve shearing and fracturing. Since the compressive strength of rock in the formation under confining pressure is higher than its shear strength, the torque generated by the rotation of the PDC drill bit keeps the PCD composite cutting edge continuously sharp, cutting into the rock. Once the shear force on the rock exceeds its shear strength limit, the cutting edge of the PDC drill bit effectively shears and fractures the rock.

[0004] In practical applications, it is difficult to achieve axial force balance of the cutting teeth in PDC drill bits. The instantaneous rotation center point of the drill bit, formed by the inner cone end of the cutter blade, is prone to lateral displacement, causing the drill bit to spin and resulting in lateral vibration, which in turn leads to rapid wear of the cutting elements. Due to this lateral vibration, the cutting teeth at the crown of the concave cutter blade in conventional PDC drill bits are susceptible to significant impact and breakage. The large load on the crown also leads to premature wear and failure of the drill bit. Furthermore, when drilling in rock formations with large dip angles, it is impossible to guarantee stable inclination and drilling efficiency. With increasing drilling depth and the use of larger drill bits, in complex and difficult-to-drill formations such as hard formations, mixed hard and soft formations, and gravelly formations, the crown of the concave cutter blade in conventional PDC drill bits is prone to wear damage, and the cutting teeth are susceptible to impact damage, resulting in low drill bit life and affecting drilling efficiency and effectiveness.

[0005] Therefore, there is an urgent need in this field to study a low-vibration, high-stability PDC drill bit and a drilling tool having such a PDC drill bit. Summary of the Invention

[0006] To address the above problems, the present invention provides a low-vibration, high-stability PDC drill bit and a drilling tool having the PDC drill bit.

[0007] According to one aspect of the present invention, a low-vibration, high-stability PDC drill bit is provided, the drill bit comprising: a drill bit body, the drill bit body including a plurality of blades arranged circumferentially, each blade having a cone portion located radially inward and a head located radially outward, the head having a crown and a stabilizing portion located radially inward of the crown, the stabilizing portion having a stepped profile with an upper radially inward convex and a lower radially outward concave.

[0008] According to one embodiment of the present invention, the stabilizing portion includes an arcuate portion, a first straight section, a conical section, and a second straight section arranged sequentially from top to bottom, wherein the inner edge of the first straight section is closer to the central axis of the drill bit body than the inner edge of the second straight section.

[0009] According to one embodiment of the present invention, the head has a first height dimension h1 and a second height dimension h2, the first height dimension h1 being the distance between the top of the first straight segment and the bottom of the second straight segment, and the second height dimension h2 being the projection distance of the line connecting the crown top and the lowest point of the cone on the central axis, the first height dimension h1 being equal to one-third to one-half of the second height dimension h2.

[0010] According to one embodiment of the present invention, the arcuate portion and the conical portion are provided with cutting teeth, while the first straight portion, the conical portion and the second straight portion are not provided with cutting teeth.

[0011] According to one embodiment of the present invention, the cone gradually concave from the outside to the center, and the inner cone angle formed by the upper surface of the cone and the central axis of the drill bit body is greater than 45°.

[0012] According to one embodiment of the present invention, the plurality of cutter wings include main cutter wings and secondary cutter wings arranged alternately in the circumferential direction, wherein the inner end point of the main cutter wings is closer to the central axis of the drill bit body than the inner end point of the secondary cutter wings.

[0013] According to one embodiment of the present invention, the number of cutting teeth on the cone of the main blade is 1.5 to 2 times the number of cutting teeth on the cone of the secondary blade.

[0014] According to one embodiment of the present invention, the plurality of blades are helically twisted along the central axis.

[0015] According to one embodiment of the present invention, each of the blades is provided with cutting teeth on the surface of the crown top and the radially outer surface of the crown top, the cutting teeth including front cutting teeth and rear cutting teeth.

[0016] According to one embodiment of the present invention, the height of the rear row of cutting teeth is 1.5-2 mm lower than the height of the front row of cutting teeth.

[0017] According to one embodiment of the present invention, the drill bit body further includes a water-eye nozzle, the water-eye nozzle including a central water-eye nozzle located radially inner and a peripheral water-eye nozzle located radially outer, the central water-eye nozzle and the peripheral water-eye nozzle being staggered in the circumferential direction.

[0018] According to one embodiment of the present invention, the peripheral water eye nozzle is disposed on the water eye base, and there is a height difference between the water spray nozzle of the peripheral water eye nozzle and the water spray nozzle of the central water eye nozzle.

[0019] According to another aspect of the present invention, a drilling tool is provided, the drilling tool comprising a low-vibration, high-stability PDC drill bit as described in any of the above embodiments.

[0020] By adopting the above technical solutions, the low-vibration, high-stability PDC drill bit and drill string provided by this invention optimizes the drill bit's profile. The inner head shape of the PDC drill bit near the center adopts a stepped two-section design, which allows the PDC drill bit to form a core column in the core area during drilling. At the same time, a gap is left between the core column and the lower part of the inner side of the drill bit. This not only limits the lateral vibration and vortex of the PDC drill bit, but also improves the heat dissipation and cuttings transport of the drill bit. It avoids the strong lateral jumping caused by high-speed rotation of large-size PDC drill bits during drilling in hard and soft mixed formations, reduces the impact on the cutting teeth of the drill bit shoulder, effectively avoids tooth breakage and excessive wear in the core and inner cone parts, significantly improves the service life of the drill bit, and improves the anti-skewing and straightening effect of the drill bit. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This illustrates a cross-sectional structure of the crown of a prior art PCD drill bit; Figure 2 A schematic diagram of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown; Figure 3 A top view of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of a partial head section profile of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown. Figure 5 A schematic diagram of the cutting tooth distribution of a PDC drill bit according to an embodiment of the present invention is shown; Figure 6A schematic diagram of the bottom hole shape during the drilling process of a PDC drill bit according to an embodiment of the present invention is shown.

[0022] List of reference numerals in the attached diagram: 100. Drill bit body; 110. Cutting blade; 110A. Main cutting blade; 110B. Secondary cutting blade; 111. Taper section; 112. Head; 112a. Crown; 112b. Stabilizing section; 112b1. Arc-shaped section; 112b2. First straight section; 112b3. Taper section; 112b4. Second straight section; 112c. Outer periphery; 112c1. Outer arc-shaped section; 112c2. Outer straight section; 113. Cutting teeth; 113a. Front row Cutting teeth; 113b, rear cutting teeth; 113c, arc-shaped teeth / gauge-maintaining teeth; 120, water inlet nozzle; 121, central water inlet nozzle; 122, peripheral water inlet nozzle; 123, water inlet base; 200, connector; A, central axis; C, center point; h1, first height dimension; h2, second height dimension; R1, drill bit radius; R2, crown curvature radius; R3, peripheral arc curvature radius; R4, inner cone rotation radius; H, core column height.

[0023] GD, crown top; NZ, inner cone; WZ, outer cone; J, shoulder; BJ, diameter-preserving part. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] The terms "comprising" and "having," and any variations thereof, used in the specification and accompanying drawings of this invention are intended to cover non-exclusive inclusion; the terms "first," "second," etc., used in the specification, claims, or accompanying drawings of this invention are used to distinguish different objects, not to describe a particular order. "A plurality of" means two or more, unless otherwise explicitly specified.

[0026] Furthermore, the reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0027] Figure 1The cross-sectional structure of the crown of a prior art PCD drill bit is shown in the figure. The crown cross-sectional structure of the PCD drill bit mainly consists of the following five parts: crown top GD, inner cone NZ, outer cone WZ, shoulder J, and diameter-maintaining section BJ.

[0028] The crown-top GD (Ground Dip) is the first part of the drill bit to penetrate the formation during drilling, and its radius always varies depending on the formation conditions. Normally, to accelerate the drill bit's penetration into the formation, the radius of the crown-top GD is relatively smaller when penetrating soft formations; while when facing hard formations or mixed hard and soft formations, the radius of the crown-top GD is larger to ensure even force distribution during penetration and prevent damage to individual teeth due to excessive localized stress.

[0029] During drilling, lateral forces are generated on the drill bit. The function of the inner cone (NZ) is to prevent the drill bit from shifting laterally, to stop these excessive lateral forces, and to maintain the stability of the drill bit's operation. Generally speaking, the inner cone is shallower in hard formations and deeper in soft formations.

[0030] The outer cone section (WZ), also known as the flank, comes in two types: curved and straight. Normally, when encountering harder formations with more cutting teeth, the outer cone section (WZ) is designed to be longer, while for softer formations, it is designed to be shorter.

[0031] The shoulder J is also a key part of the drilling, as it determines the transition from the flank to the diameter-maintaining section BJ. It is the part with the largest radius in the crown and suffers the most severe wear. At the same time, impact loads act directly on this part.

[0032] During drilling, the diameter protection unit (BJ) ensures that the diameter of the wellbore does not change due to drill bit wear, thus maintaining the stability of the wellbore.

[0033] In practical applications, existing PDC drill bits struggle to achieve axial force balance on the cutting teeth. The instantaneous rotation center point of the drill bit, formed by the inner cone end of the cutter blade, is prone to lateral displacement, causing the drill bit to spin and resulting in lateral vibration. This leads to rapid wear of the cutting elements. The presence of lateral vibration makes the cutting teeth at the crown (GD) of the concave cutter blade in conventional PDC drill bits susceptible to significant impact and breakage. Furthermore, the large load borne at the crown (GD) causes premature wear and failure of the drill bit.

[0034] To address the shortcomings of existing PDC drill bits, one objective of this invention is to provide a low-vibration, high-stability PDC drill bit. Figure 2 A schematic diagram of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown; Figure 3 A top view of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown; Figure 4A partial head section profile of a low-vibration, high-stability PDC drill bit according to an embodiment of the present invention is shown. In this document, the terms "radial inner side," "inner side," "inner," "radial outer side," "outer side," and "outer" are all referenced to the central axis A of the drill bit, which is located at the innermost side. Along the radial direction, the closer to the outer surface of the drill bit, the further outward it is. The terms "top," "bottom," "apex," and "bottom end" are referenced to the state where the central axis A of the drill bit is vertical and the drill bit crown is facing upwards.

[0035] like Figure 2-4 As shown, the low-vibration, high-stability PDC drill bit of this embodiment includes a drill bit body 100, on which a plurality of cutter wings 110 are arranged circumferentially. Each cutter wing 110 has a cone portion 111 located radially inward and a head 112 located radially outward. The head 112 has a crown 112a and a stabilizing portion 112b located radially inward of the crown 112a. The stabilizing portion 112b has a stepped profile with an upper radially inward convex and a lower radially outward concave (e.g., ...). Figure 4 (As shown).

[0036] The low-vibration, high-stability PDC drill bit provided by this invention optimizes the drill bit's profile. The inner head shape near the center of the PDC drill bit adopts a stepped two-section design, which allows the PDC drill bit to form a core column in the core area during drilling. At the same time, a gap is left between the core column and the lower part of the inner side of the drill bit. This not only limits the lateral vibration and vortex of the PDC drill bit, but also improves the heat dissipation and cuttings transport of the drill bit. It avoids the strong lateral jumping caused by high-speed rotation of large-size PDC drill bits during drilling in hard and soft mixed formations, reduces the impact on the cutting teeth of the drill bit shoulder, and effectively avoids tooth breakage and excessive wear in the core and inner cone parts, significantly improving the service life of the drill bit, while also improving the anti-skewing and straightening effect of the drill bit.

[0037] refer to Figure 2 The drill bit body 100 is fixedly mounted on the connector 200, for example, the drill bit body 100 and the connector 200 can be connected by welding. The drill bit body 100 has multiple cutter wings 110 arranged circumferentially, each cutter wing 110 having a conical portion 111 located radially inward and a head 112 located radially outward. It is understood that the conical portion 111 and the head 112 are integrally connected, without a physical dividing line between them; here, for ease of description, they are divided into two parts. The head 112 can be further divided into a crown 112a, a stabilizing portion 112b located radially inward of the crown 112a, and a peripheral portion 112c located radially outward of the crown 112a. The stabilizing portion 112b has a stepped profile that is convex inward at the top (i.e., protruding radially inward) and concave outward at the bottom (i.e., recessed radially outward).

[0038] In some embodiments, such as Figure 4 As shown, the stabilizing section 112b is provided with an arc-shaped section 112b1, a first straight section 112b2, a tapered section 112b3, and a second straight section 112b4 sequentially from top to bottom. The drill bit body 100 has a central axis A, and the first straight section 112b2 and the second straight section 112b4 can extend parallel to the central axis A. The edge of the inner contour of the first straight section 112b2 is closer to the central axis A of the drill bit body 100 than the edge of the inner contour of the second straight section 112b4, causing the first straight section 112b2 to bulge radially towards the central axis A compared to the second straight section 112b4. The tapered section 112b3 connects the first straight section 112b2 and the second straight section 112b4 in a beveled shape. The first straight section 112b2 facilitates the formation of a core column in the core region of the PDC drill bit, and gives the core column a certain length and volume, enabling it to limit the lateral vibration and vortex of the PDC drill bit. The conical section 112b3 and the second straight section 112b4 create clearance space, allowing a gap between the core column and the lower inner side of the drill bit, improving heat dissipation and cuttings transport. These two optimizations prevent the strong lateral movement of large-diameter PDC drill bits during high-speed rotation in hard and soft mixed formations, reduce the impact on the cutting teeth at the drill bit shoulder, effectively prevent tooth breakage and excessive wear in the core and inner conical sections, significantly improve drill bit lifespan, and enhance the drill bit's anti-deviation and straightening performance.

[0039] In some embodiments, the bottom end of the second straight section 112b4 may be connected to the radially outer side (specifically, the outer edge) of the cone 111. The head 112 may have a first height dimension h1 and a second height dimension h2. The first height dimension h1 is the distance between the highest point of the first straight section 112b2 and the lowest point of the second straight section 112b4 (i.e., where the second straight section 112b4 connects to the cone 111). The second height dimension h2 is the projection distance of the line connecting the highest point of the crown 112a and the lowest point of the cone 111 (i.e., the center point C of the inner cone) onto the central axis A, and can also be regarded as the distance from the highest point of the crown 112a to the radial plane passing through the center point C (i.e., the plane perpendicular to the central axis A). The first height dimension h1 may be equal to one-third to one-half of the second height dimension h2, which ensures that the core column has a certain length and volume, so that it can better limit the lateral vibration and vortex of the PDC drill bit.

[0040] In some embodiments, the arcuate portion 112b1 and the conical portion 111 are provided with cutting teeth 113. For example, both the arcuate portion 112b1 and the conical portion 111 may be provided with a single row of teeth. However, the first straight section 112b2, the conical section 112b3, and the second straight section 112b4 are not provided with cutting teeth 113. This ensures that a core column with sufficient strength is formed in the core region of the PDC drill bit. Optionally, the first straight section 112b2 may be provided with one or two cutting teeth 113 near the arcuate portion 112b1 to facilitate calibrating the cut core column.

[0041] In some embodiments, the cone 111 gradually curves downward from the outside to the center, and the inner cone angle α formed by the upper surface of the cone 111 and the central axis A of the drill bit body 100 is greater than 45°, for example, the inner cone angle α can be 75°. Setting the inner cone angle to this range can obtain stronger guidance and impact resistance. For a 16" drill bit, the radius of rotation R4 formed by the inner cone line can be 40-50 mm.

[0042] In some embodiments, the plurality of cutter wings 110 may include main cutter wings 110A and secondary cutter wings 110B arranged alternately in a circumferential direction, wherein the inner end point of the main cutter wing 110A is closer to the central axis A of the drill body 100 than the inner end point of the secondary cutter wing 110B. Figure 2-3 In the illustrated embodiment, the PDC drill bit includes three main blades 110A and three secondary blades 110B, which are arranged alternately in the circumferential direction. The conical portion 111 of the main blades 110A extends to a position closer to the center point C. The arrangement of the cutting teeth 113 on the main blades 110A and the secondary blades 110B can differ. For example, the number of cutting teeth 113 on the conical portion 111 of the main blades 110A can be 1.5 to 2 times the number of cutting teeth 113 on the conical portion 111 of the secondary blades 110B.

[0043] The drill bit body 100 may further include a water jet nozzle 120. The water jet nozzle 120 may include a central water jet nozzle 121 located radially inward and a peripheral water jet nozzle 122 located radially outward, with the central and peripheral nozzles staggered circumferentially. Both the central and peripheral nozzles are located near the cutter wing 110 and spray towards the cutter wing 110, thereby improving the cleaning effect on the cutting teeth 113. Optionally, in some embodiments, the peripheral nozzle 122 is located near the shoulder of the cutter wing 110 and is disposed on the water jet base 123, resulting in a height difference between the nozzle of the peripheral nozzle 122 and the nozzle of the central nozzle 121. The outer water nozzle 122 is provided for the shoulder cutting tooth 113 and arranged on the water nozzle base 123. This can reduce the distance between the nozzle and the bottom of the well, and can efficiently clean and cool the cutting tooth 113 in real time. In addition, the outer water nozzle 122 and the central water nozzle 121 have a certain height difference, which can make the internal and external flow fields of the drill bit complementary and quickly move the cuttings.

[0044] Optionally, the three main blades 110A and the three secondary blades 110B can be spirally twisted around the central axis A, with a twist angle of 10-20°, in order to optimize the drill bit flow field.

[0045] The crown apex 112a and the outer periphery 112c are the main areas for cutting. Therefore, cutting teeth 113 are provided on the surfaces of both the crown apex 112a and the outer periphery 112c. The cutting teeth 113 can be welded to the surfaces of the crown apex 112a and the outer periphery 112c. The cutting teeth 113 of the crown apex 112a and the outer periphery 112c can include a front row of cutting teeth 113a and a rear row of cutting teeth 113b. The height of the rear row of cutting teeth 113b is 1.5-2 mm lower than the height of the front row of cutting teeth 113a. The back slope angle of the rear row of cutting teeth 113b can be 14-23°. The number, layout, size, and back slope angle of the front row of cutting teeth 113a and the rear row of cutting teeth 113b can be set according to the properties of the formation to be drilled.

[0046] Figure 2-5 The drill bit shown is a 16" drill bit. The drill bit radius R1 of this type of drill bit is 203.2 mm, and the radius of curvature R2 of the crown 112a can be 30-50 mm. The outer portion 112c includes an arc-shaped portion 112c1 and a straight section 112c2. The radius of curvature R3 of the arc-shaped portion 112c1 can be 100-150 mm. The straight section 112c2 is the gauge-maintaining portion of the PDC drill bit, and its outer surface is provided with arc-shaped teeth and / or gauge-maintaining teeth 113c. The diameter of the cutting teeth 113 on this PDC drill bit is 16 mm.

[0047] Figure 5This diagram illustrates the distribution of cutting teeth 113 in a PDC drill bit according to an embodiment of the present invention. Six blades 110 are radially sectioned from the central axis A to obtain cross-sections of the six blades 110. These six cross-sections are then aligned and stacked along the central axis A, resulting in the projection of all cutting teeth 113 as shown. Figure 5 As shown. The cone 111 has 19 cutting teeth 113 on its straight line, and the head 112 has 64 cutting teeth 113. The number and arrangement of the cutting teeth 113 can be changed according to needs and the size of the PDC drill bit.

[0048] Another object of the present invention is to provide a drill bit comprising a low-vibration, high-stability PDC drill bit as described in any of the above embodiments.

[0049] Figure 6 A schematic diagram of the bottom hole configuration during drilling using a PDC drill bit according to an embodiment of the present invention is shown. Because the PDC drill bit of the present invention includes a stepped head shape, with cutting teeth 113 arranged on the head shape, the drill bit rotates along the central axis A. After the cutting teeth 113 cut the formation, they form a cylindrical core column of height H in the radial direction. The core column acts on the conical core portion inside the drill bit to stabilize the drill bit, avoid lateral vibration of the drill bit, reduce impact damage to the cutting teeth, and improve the service life of the drill bit.

[0050] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A low-vibration, high-stability PDC drill bit, characterized in that, include: The drill bit body (100) includes a plurality of cutter wings (110) arranged circumferentially. Each cutter wing (110) has a cone (111) located radially inward and a head (112) located radially outward. The head (112) has a crown (112a) and a stabilizing portion (112b) located radially inward of the crown (112a). The stabilizing portion (112b) has a stepped profile that is radially convex inward at the top and radially concave outward at the bottom.

2. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, The stabilizing part (112b) includes an arc-shaped part (112b1), a first straight section (112b2), a conical section (112b3), and a second straight section (112b4) arranged sequentially from top to bottom. The inner edge of the first straight section (112b2) is closer to the central axis (A) of the drill body (100) than the inner edge of the second straight section (112b4).

3. The low-vibration, high-stability PDC drill bit according to claim 2, characterized in that, The head (112) has a first height dimension (h1) and a second height dimension (h2), the first height dimension (h1) being the distance between the top of the first straight section (112b2) and the bottom of the second straight section (112b4), the second height dimension (h2) being the projection distance of the line connecting the crown (112a) and the lowest point of the cone (111) on the central axis (A), and the first height dimension (h1) being equal to one-third to one-half of the second height dimension (h2).

4. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, The arc-shaped portion (112b1) and the conical portion (111) are provided with cutting teeth (113), while the first straight portion (112b2), the conical portion (112b3) and the second straight portion (112b4) are not provided with cutting teeth (113).

5. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, The cone (111) gradually concaves from the outside to the center, and the inner cone angle formed by the upper surface of the cone (111) and the central axis (A) of the drill bit body (100) is greater than 45°.

6. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, The plurality of cutter wings (110) include main cutter wings (110A) and secondary cutter wings (110B) arranged alternately in the circumferential direction, wherein the inner end point of the main cutter wing (110A) is closer to the central axis (A) of the drill body (100) than the inner end point of the secondary cutter wing (110B).

7. The low-vibration, high-stability PDC drill bit according to claim 6, characterized in that, The number of cutting teeth (113) on the cone (111) of the main blade (110A) is 1.5 to 2 times the number of cutting teeth (113) on the cone (111) of the secondary blade (110B).

8. The low-vibration, high-stability PDC drill bit according to claim 6, characterized in that, The plurality of blades (110) are spirally twisted along the central axis (A).

9. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, Each blade (110) has cutting teeth (113) on the surface of the crown top (112a) and the radially outer side of the crown top (112a), the cutting teeth (113) including front cutting teeth (113a) and rear cutting teeth (113b).

10. The low-vibration, high-stability PDC drill bit according to claim 9, characterized in that, The height of the rear cutting teeth (113b) is 1.5-2mm lower than the height of the front cutting teeth (113a).

11. The low-vibration, high-stability PDC drill bit according to claim 1, characterized in that, The drill bit body (100) also includes a water jet nozzle (120), which includes a central water jet nozzle (121) located on the radial inner side and a peripheral water jet nozzle (122) located on the radial outer side. The central water jet nozzle (121) and the peripheral water jet nozzle (122) are staggered in the circumferential direction.

12. The low-vibration, high-stability PDC drill bit according to claim 11, characterized in that, The peripheral water eye nozzle (122) is set on the water eye base (123), and there is a height difference between the spray nozzle of the peripheral water eye nozzle (122) and the spray nozzle of the central water eye nozzle (121).

13. A drilling tool, characterized in that, The drilling tool includes a low-vibration, high-stability PDC drill bit as described in any one of claims 1-12.

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