PDC drill bit

Abstract

This invention discloses a PDC drill bit, comprising: multiple cutter wings evenly spaced along the circumference of the PDC drill bit; and multiple front-row cutting teeth arranged sequentially around the central axis of the PDC drill bit from its center outwards on the multiple cutter wings. Each group of three adjacent front-row cutting teeth forms a triangular distribution around the central axis of the PDC drill bit on three of the cutter wings. During rotary drilling, a portion of the cutting force of the three front-row cutting teeth in the same group cancels each other out, thus forming a more stable cutting structure, minimizing unbalanced forces, enhancing drill bit stability, and improving impact resistance. Furthermore, by achieving graded optimization of the tooth density of the multiple front-row cutting teeth, rock-breaking efficiency can be effectively improved, while also promoting uniform wear of the multiple front-row cutting teeth and improving anti-wear performance.

Description

Technical Field

[0001] This invention relates to the field of oil drilling and production technology, and in particular, to a PDC drill bit. Background Technology

[0002] As exploration and development continue to deepen, oil and gas exploration and development is moving from shallow to deep and ultra-deep strata. This presents challenges such as increasingly complex geological formations, including the deep strata in the Tarim Basin and the southern margin of Xinjiang, the marine facies and Sinian system in Sichuan and Chongqing, and the Songliao igneous rocks in key exploration and development areas, as well as tight oil and gas fields. These areas often have difficult-to-drill formations with high abrasiveness and extremely poor drillability, which poses challenges such as low rock-breaking efficiency, slow drilling speed, long drilling cycle, and high cost for PDC drill bits. For example, the deep strata in the Tarim Basin are extremely abrasive, with PDC drill bits achieving a drillability rating of over 10. The average footage per PDC drill bit is only 47.1m, with an average drilling speed of 0.72m / h. The conglomerate layer of the Zhenzhuchong Formation in Sichuan has a compressive strength of 332MPa and a PDC drillability rating of 13. The Xujiahe Formation is extremely abrasive, known as a "whetstone," with PDC drill bits achieving a drillability rating of over 10, a maximum compressive strength of 210MPa, and an average mechanical drilling speed of 1.3m / h. The deep strata below the Permian system in the Gaoshiti-Moxi area have a drillability rating of over 7. The Canglangpu Formation has an average footage per PDC drill bit of 40m and an average mechanical drilling speed of 0.98m / h. The strata below the Yingcheng Formation in the deep Songliao Formation are mainly composed of volcanic breccia, tuff, and rhyolite, which are extremely abrasive. The drillability of PDC drill bits is 8-12.4, the uniaxial compressive strength is 220MPa, the drilling speed is slow, the drill bit teeth breakage and wear are severe, the well section length accounts for about 20% of the total well length, and the drill bit usage exceeds 58%.

[0003] In existing technologies, to improve the rock-breaking effect of PDC drill bits in formations with extremely poor drillability, the following tooth arrangement designs are commonly used to optimize the abrasion resistance of PDC drill bits: (1) increasing the tooth density of the drill bit by reducing the size of the cutting teeth and increasing the number of cutting teeth and blades; (2) increasing the tooth density by using a row of cutting teeth along the same track to improve the abrasion resistance of the drill bit. Although these two methods improve the rock-breaking effect to a certain extent, they require reducing the aggression of the drill bit in exchange for the life of the drill bit, which greatly reduces the effectiveness of the drill bit in application. Summary of the Invention

[0004] The purpose of this invention is to provide a PDC drill bit to solve the technical problem in the prior art that although increasing the tooth density of the drill bit improves the rock breaking effect to a certain extent, it requires reducing the aggressiveness of the drill bit in exchange for the life of the drill bit, resulting in poor application effect of the drill bit.

[0005] The above-mentioned objectives of the present invention can be achieved by the following technical solutions:

[0006] The present invention provides a PDC drill bit, comprising: a plurality of blades evenly spaced along the circumference of the PDC drill bit; a plurality of front row cutting teeth arranged one by one on the plurality of blades from the center of the PDC drill bit outward around the central axis of the PDC drill bit, wherein every three adjacent front row cutting teeth form a group and are distributed in a triangle around the central axis of the PDC drill bit on three of the blades.

[0007] In embodiments of the present invention, the tooth radius of the plurality of front row cutting teeth is arranged to gradually increase along the arrangement direction.

[0008] In embodiments of the present invention, the tooth density of the plurality of front cutting teeth in the region near the center of the PDC drill bit is less than that in the region near the outer periphery of the PDC drill bit.

[0009] In an embodiment of the present invention, the PDC drill bit includes a core and a shoulder extending from the center of the PDC drill bit to its outer periphery, wherein a plurality of front-row cutting teeth are distributed in the core to form a core tooth group, and a plurality of front-row cutting teeth are distributed in the shoulder to form a shoulder tooth group; wherein the tooth density of the core tooth group is less than the tooth density of the shoulder tooth group.

[0010] In an embodiment of the present invention, the distance between the projections of the plurality of front cutting teeth in the core tooth group onto the radial crown profile of the PDC drill bit is the core tooth spacing J1, and the distance between the projections of the plurality of front cutting teeth in the shoulder tooth group onto the radial crown profile of the PDC drill bit is the shoulder tooth spacing J2, with the following relationship: 1.5J2≤J1≤2J2.

[0011] In an embodiment of the present invention, the shoulder tooth spacing J2 is 3mm to 4mm.

[0012] In an embodiment of the present invention, the PDC drill bit further includes a gauge-maintaining section connected to the shoulder, and a plurality of the front row cutting teeth are distributed in the gauge-maintaining section to form a gauge-maintaining tooth group; wherein the tooth density of the shoulder tooth group is less than the tooth density of the gauge-maintaining tooth group.

[0013] In an embodiment of the present invention, the spacing between the projections of the plurality of front row cutting teeth in the gauge-maintaining tooth group onto the radial crown profile of the PDC drill bit is the gauge-maintaining tooth spacing J3, which is 2mm to 3mm.

[0014] In an embodiment of the present invention, the PDC drill bit further includes a plurality of rear cutting teeth, wherein at least a portion of the plurality of rear cutting teeth and the plurality of front cutting teeth are disposed on the plurality of blades in a one-to-one correspondence, and the corresponding front cutting teeth and the rear cutting teeth have the same tooth radius.

[0015] In an embodiment of the present invention, the distribution angles of the corresponding front row of cutting teeth and the rear row of cutting teeth in the circumferential direction of the PDC drill bit differ by 120° to 200°.

[0016] In an embodiment of the present invention, the distribution angles of the corresponding front row of cutting teeth and the rear row of cutting teeth in the circumferential direction of the PDC drill bit differ by 180°±10°.

[0017] In an embodiment of the present invention, the height of the front row of cutting teeth is higher than the height of the corresponding rear row of cutting teeth.

[0018] In an embodiment of the present invention, the height difference between the corresponding front row of cutting teeth and the rear row of cutting teeth is greater than 0 and does not exceed 1.5 mm.

[0019] In embodiments of the present invention, the number of blades is six or more.

[0020] The features and advantages of this invention are:

[0021] The PDC drill bit of the present invention arranges multiple front-row cutting teeth one by one around the central axis of the PDC drill bit on multiple blades from the inside out. Each group of three adjacent front-row cutting teeth forms a triangular distribution around the central axis of the PDC drill bit on three of the blades. This allows a portion of the cutting force of the three front-row cutting teeth in the same group to cancel each other out during rotary drilling, thus forming a more stable cutting structure, minimizing unbalanced forces, enhancing the drill bit's stability, and improving its impact resistance. Furthermore, compared to existing technologies, with the same number of front-row cutting teeth A, the present invention utilizes a special arrangement method to better cover the working surface of the drill bit with the cutting trajectory formed by the multiple front-row cutting teeth A around the central axis A of the PDC drill bit.

[0022] The PDC drill bit of the present invention has a lower tooth density in the region near the center of the PDC drill bit than in the region near the outer periphery of the PDC drill bit. This achieves graded optimization of the tooth density of the multiple front cutting teeth in the radial direction of the PDC drill bit. The multiple front cutting teeth with lower tooth density near the center ensure that the PDC drill bit has a certain degree of aggression, while the multiple front cutting teeth with higher tooth density near the outer periphery ensure that the PDC drill bit has a certain degree of anti-wear performance. This effectively improves the rock-breaking efficiency of each front cutting tooth, while also promoting uniform wear of multiple front cutting teeth and improving the overall anti-wear performance of the PDC drill bit.

[0023] The PDC drill bit of the present invention, by setting front and rear rows of cutting teeth with the same tooth radius, allows the cutting depth to be controlled by utilizing the rear rows of cutting teeth when the front rows of cutting teeth are not worn down to the same cutting height as the rear rows of cutting teeth, thereby preventing overload and premature damage to the front rows of cutting teeth. When the front rows of cutting teeth are worn down to the same cutting height as the rear rows of cutting teeth, the front and rear rows of cutting teeth cut the formation simultaneously, but the rear rows of cutting teeth become the main cutting teeth. This increases the tooth density of the PDC drill bit without reducing its aggressiveness, ensuring its anti-abrasion and impact resistance, and improving its rock-breaking effect in ultra-hard and poorly drillable formations. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the arrangement of multiple front-row cutting teeth in the circumferential direction of the PDC drill bit in this invention.

[0026] Figure 2 This is a schematic diagram showing the arrangement of multiple front-row cutting teeth projected onto the radial crown profile of the PDC drill bit in this invention.

[0027] Figure 3 This is a schematic diagram of the radial arrangement of the front and rear cutting teeth in the PDC drill bit according to the present invention.

[0028] Figure 4 This is a schematic diagram of the tooth arrangement of the front row of cutting teeth and part of the rear row of cutting teeth in the circumferential direction of the PDC drill bit in this invention.

[0029] Figure 5 This is a schematic diagram of the circumferential arrangement of the front and rear cutting teeth in the PDC drill bit according to the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] like Figure 1 and Figure 2As shown, the present invention provides a PDC drill bit, comprising: multiple blades evenly spaced along the circumference of the PDC drill bit; multiple front row cutting teeth A, arranged one by one around the central axis Z of the PDC drill bit from the center of the PDC drill bit outwards on the multiple blades, wherein every three adjacent front row cutting teeth A form a group and are distributed in a triangular pattern around the central axis Z of the PDC drill bit on three of the blades.

[0032] The PDC drill bit of the present invention arranges multiple front-row cutting teeth A on multiple blades through a special arrangement. This allows the cutting force of three front-row cutting teeth A in the same group to cancel each other out during rotary drilling, thereby forming a more stable cutting structure, minimizing unbalanced forces, enhancing the stability of the drill bit, and improving its impact resistance. Compared with the prior art, when the number of front-row cutting teeth A is the same, the present invention uses a special arrangement to arrange multiple front-row cutting teeth A, which allows the cutting trajectory formed by multiple front-row cutting teeth A around the central axis A of the PDC drill bit to better cover the working surface of the drill bit.

[0033] Specifically, in some embodiments of the present invention, multiple front-row cutting teeth A are arranged one by one on multiple blades in a counterclockwise direction N around the central axis Z of the PDC drill bit, starting from the center of the PDC drill bit. In other embodiments of the present invention, multiple front-row cutting teeth A are arranged one by one on multiple blades in a clockwise direction around the central axis Z of the PDC drill bit, starting from the center of the PDC drill bit. Every three adjacent front-row cutting teeth A form a group, arranged in a triangle around the central axis Z of the PDC drill bit on three blades. This means that three front-row cutting teeth A with similar tooth radius R form a group arranged in a triangle, and the central axis Z of the PDC drill bit is located within this triangle. Preferably, the distribution angles of the three front-row cutting teeth A in each triangular distribution group in the circumferential direction of the PDC drill bit differ by 120°, so that the cutting force can be better canceled out, resulting in the best stability.

[0034] In some embodiments of the present invention, the tooth radius R of the plurality of front cutting teeth A is arranged to gradually increase along its arrangement direction, and three front cutting teeth A with similar tooth radius R are grouped together. The arrangement direction of the plurality of front cutting teeth A is similar to the extension direction from the inside to the outside along an irregular spiral.

[0035] It should be noted that this invention only limits the arrangement design of multiple front-row cutting teeth A, and does not specifically limit the number of front-row cutting teeth A. The number of front-row cutting teeth A can be a multiple of three, or one or two more than a multiple of three. The extra one or two can be reasonably arranged on the corresponding blades according to the arrangement space on the blade wings, as long as it meets the requirements of tooth density. For example, 22 teeth can be set as in one embodiment of this invention, or 28 teeth can be set as in another embodiment of this invention. Of course, other numbers such as 21, 23, ..., 27 can also be set as needed.

[0036] The number of cutter wings can be designed according to the drillability rating of the formation to which the PDC drill bit is applied. For example, in some embodiments of the present invention, the number of cutter wings is six or more, which is particularly suitable for formations with a drillability rating of 6 or higher, and can also be used for formations with a drillability rating of less than 6. Optionally, the number of cutter wings is three, four or five, which is suitable for formations with a drillability rating of less than 6.

[0037] Based on the arrangement space and distribution angle on multiple blades, and the required tooth density of the front cutting teeth A, the three front cutting teeth A of each group are set on three reasonable blades. To avoid excessive tooth density of the front cutting teeth A on the same blade, in some embodiments of the present invention, the three front cutting teeth A of the first group are distributed on three blades B, while the three front cutting teeth A of the second group are distributed on three different blades B'; in other embodiments of the present invention, the front cutting teeth A with the largest tooth radius R in the first group and the front cutting teeth A with the smallest tooth radius R in the second group are distributed on different blades.

[0038] For ease of description, the multiple front-row cutting teeth A are numbered according to their arrangement order. Taking 22 front-row cutting teeth A as an example, the 22 front-row cutting teeth A are sequentially named front-row cutting tooth 1, front-row cutting tooth 2, front-row cutting tooth 3, ..., front-row cutting tooth 19, front-row cutting tooth 20, front-row cutting tooth 21, and front-row cutting tooth 22. There are 6 cutting blades, including three long blades B and three short blades B' arranged alternately along the circumference of the PDC drill bit. The long blades B are positioned closer to the center of the PDC drill bit than the short blades B'. Front-row cutting teeth 1, 2, and 3 are arranged in a triangular formation on the three long blades B, while front-row cutting teeth 4, 5, and 6 are arranged in a... Three short blade wings B' are arranged in a triangular pattern. Front cutting teeth 7, 8, and 9 are arranged in a triangular pattern on three long blade wings B. Front cutting teeth 10, 11, and 12 are arranged in a triangular pattern on three short blade wings B'. Front cutting teeth 13, 14, and 15 are arranged in a triangular pattern on three long blade wings B. Front cutting teeth 16, 17, and 18 are arranged in a triangular pattern on three short blade wings B'. Front cutting teeth 19, 20, and 21 are arranged in a triangular pattern on three long blade wings B. Front cutting tooth 22 is arranged on the short blade wing B' where front cutting tooth 16 is located.

[0039] like Figure 1 and Figure 2 As shown, in the embodiment of the present invention, the tooth density of the multiple front-row cutting teeth A in the region near the center of the PDC drill bit is less than the tooth density in the region near the outer periphery of the PDC drill bit. Through graded optimization of the tooth density of the multiple front-row cutting teeth A in the radial direction of the PDC drill bit, the lower tooth density near the center of the multiple front-row cutting teeth A ensures that the PDC drill bit has a certain degree of aggression, while the higher tooth density near the outer periphery ensures that the PDC drill bit has a certain degree of anti-abrasion performance. This effectively improves the rock-breaking efficiency of each front-row cutting tooth A, while also promoting uniform wear of the multiple front-row cutting teeth A, thus enhancing the overall anti-abrasion performance of the PDC drill bit.

[0040] Specifically, the tooth density of the multiple front-row cutting teeth A refers to the distribution density of the multiple front-row cutting teeth A in the radial direction of the PDC drill bit. The higher the tooth density, the denser the cutting trajectory formed by rotating around the central axis Z of the PDC drill bit; the lower the tooth density, the sparser the cutting trajectory. Therefore, in order to more clearly illustrate the tooth density of the multiple front-row cutting teeth A, the multiple front-row cutting teeth A can be projected onto the radial crown contour C of the PDC drill bit. The larger the distance between the projections of the multiple front-row cutting teeth A, the lower the tooth density; the smaller the distance between the projections of the multiple front-row cutting teeth A, the higher the tooth density.

[0041] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the PDC drill bit includes a core portion D and a shoulder portion E extending from the center of the PDC drill bit to its outer periphery. A plurality of front-row cutting teeth A are distributed in the core portion D to form a core tooth group A1, and a plurality of front-row cutting teeth A are distributed in the shoulder portion E to form a shoulder tooth group A2. The tooth density of the core tooth group A1 is less than the tooth density of the shoulder tooth group A2.

[0042] Specifically, the spacing between the projections of multiple front-row cutting teeth A in the core tooth group A1 onto the radial crown profile C of the PDC drill bit is the core tooth spacing J1, and the spacing between the projections of multiple front-row cutting teeth A in the shoulder tooth group A2 onto the radial crown profile C of the PDC drill bit is the shoulder tooth spacing J2, with the relationship: 1.5J2≤J1≤2J2. In the embodiment of the present invention, the shoulder tooth spacing J2 is 3mm to 4mm.

[0043] In some embodiments of the present invention, the core tooth assembly A1 includes front cutting teeth 1, 2, 3, 4, 5, 6, 7, 8, and 9. The shoulder tooth assembly A2 includes front cutting teeth 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, and 22.

[0044] In an embodiment of the present invention, the PDC drill bit further includes a gauge-maintaining section connected to the shoulder E, and multiple front-row cutting teeth are distributed in the gauge-maintaining section to form a gauge-maintaining tooth group A3; wherein, the tooth density of the shoulder tooth group A2 is less than the tooth density of the gauge-maintaining tooth group A3. Specifically, the spacing between the projections of the multiple front-row cutting teeth A in the gauge-maintaining tooth group A3 onto the radial crown profile C of the PDC drill bit is the gauge-maintaining tooth spacing J3, which is 2mm to 3mm. Taking 28 front-row cutting teeth A as an example, the core tooth group A1 and the shoulder tooth group A2 are the same as those described above, and will not be repeated here. The gauge-maintaining tooth group A3 includes front-row cutting teeth 23, 24, 25, 26, 27, and 28.

[0045] like Figure 3 , Figure 4 as well as Figure 5 As shown, in an embodiment of the present invention, the PDC drill bit further includes a plurality of rear cutting teeth F, and at least a portion of the plurality of front cutting teeth A are disposed on the plurality of blades in a one-to-one correspondence. The corresponding front cutting teeth A and rear cutting teeth F have the same tooth radius R.

[0046] Specifically, the number of rear cutting teeth F is not specifically limited. In this embodiment, the number of rear cutting teeth F is less than the number of front cutting teeth A. Alternatively, if the installation space on multiple blades allows, the number of rear cutting teeth F can be the same as that of front cutting teeth A.

[0047] For ease of description, the multiple rear cutting teeth F are numbered according to the corresponding front cutting teeth A. In some embodiments of the present invention, the 19 rear cutting teeth F correspond one-to-one with the front cutting teeth 4 to 22, namely rear cutting teeth 4', 5', 6', 7', 8', 9', 10', 11', 12', 13', 14', 15', 16', 17', 18', 19', 20', 21', and 22'.

[0048] like Figure 4 and Figure 5 As shown, in the embodiments of the present invention, the distribution angles of the corresponding front cutting teeth A and the rear cutting teeth F in the circumferential direction of the PDC drill bit differ by 120° to 200°. By controlling the distribution angles of the corresponding front cutting teeth A and the rear cutting teeth F, the rock-breaking effect of the rear cutting teeth F can be significantly improved.

[0049] The preferred angle difference between the corresponding front row cutting teeth A and the rear row cutting teeth F in the circumferential direction of the PDC drill bit is 180°±10°. That is, the corresponding rear row cutting teeth F and the front row cutting teeth A are roughly opposite each other in the circumferential direction of the PDC drill bit. Therefore, when the corresponding rear row cutting teeth F and the front row cutting teeth A have the same height, the rear row cutting teeth F becomes the main cutting unit and has the same cutting trajectory as its corresponding front row cutting teeth A. This ensures that the effective cutting volume of the rear row cutting teeth F is similar to that of its corresponding front row cutting teeth A, thereby making the rear row cutting teeth F more capable of participating in rock breaking and cutting. This ensures the drill bit's attack capability while improving the drill bit's wear resistance and lifespan.

[0050] In some embodiments of the present invention, the height of the front row cutting teeth A is higher than the height of its corresponding rear row cutting teeth F. The heights of the front row cutting teeth A and the rear row cutting teeth F are the heights of their outward protrusions, which are also their cutting depths. Therefore, when the front row cutting teeth A has not worn down to the same height as the rear row cutting teeth F, the cutting depth can be controlled by utilizing the rear row cutting teeth F, thereby preventing overload and premature failure of the front row cutting teeth A. When the front row cutting teeth A has worn down to the same height as the rear row cutting teeth F, the front row cutting teeth F and the rear row cutting teeth A cut the formation simultaneously, but the rear row cutting teeth F become the main cutting teeth. This ensures that the attack power of the PDC drill bit does not decrease, and increases the tooth density of the PDC drill bit, guaranteeing its anti-abrasion and impact resistance, and improving its rock-breaking effect in ultra-hard, poorly drillable formations.

[0051] Specifically, the PDC drill bit is used for formations with a drillability rating of 6 to 8, corresponding to a height difference H between the front cutting teeth A and the rear cutting teeth F that is greater than 0 and does not exceed 1.5 mm. Optionally, the height difference H between the front cutting teeth A and the rear cutting teeth F is 2 mm. When the wear or chipping of the front cutting teeth A is less than 2 mm, the rear cutting teeth F limit the cutting depth; when the wear or chipping of the front cutting teeth A reaches 2 mm or more, the rear cutting teeth F participate in cutting the formation.

[0052] In other embodiments of the present invention, the corresponding front cutting teeth A and rear cutting teeth F have the same height, and the front cutting teeth A and rear cutting teeth F cut the formation simultaneously.

[0053] Specifically, the multiple front-row cutting teeth A and the multiple rear-row cutting teeth F are PDC composite plates. The size of the composite plate can be 15.88mm, 13.44mm or smaller; the type of composite plate can be a flat cutting tooth, a triangular cutting tooth, a tapered cutting tooth or other irregular cutting teeth.

[0054] The above descriptions are merely a few embodiments of the present invention. Those skilled in the art can make various modifications or variations to the embodiments of the present invention based on the content disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A PDC drill bit, characterized by, The PDC drill bit comprises: a plurality of blades which are evenly spaced along the circumference of the PDC drill bit; a plurality of front rows of cutting teeth which are arranged on the plurality of blades in a counterclockwise direction or a clockwise direction around the central axis of the PDC drill bit from the center of the PDC drill bit to the outer periphery of the PDC drill bit, and the arrangement radius of the cutting teeth gradually increases along the arrangement direction, every three adjacent cutting teeth with similar arrangement radius form a group of cutting teeth which are arranged in a triangular shape on three blades around the central axis of the PDC drill bit, and the cutting forces of a part of the three cutting teeth in the same group can be offset by each other; wherein the plurality of blades comprise three long blades and three short blades which are alternately arranged along the circumference of the PDC drill bit, the long blades are closer to the center of the PDC drill bit than the short blades; the three cutting teeth of one group of the front rows of cutting teeth are arranged in a triangular shape on the three long blades, and the three cutting teeth of another group of the front rows of cutting teeth are arranged in a triangular shape on the three short blades; the PDC drill bit comprises a core portion and a shoulder portion which extend from the center of the PDC drill bit to the outer periphery of the PDC drill bit, wherein the plurality of front rows of cutting teeth are arranged in the core portion to form a core tooth group, and the plurality of front rows of cutting teeth are arranged in the shoulder portion to form a shoulder tooth group; the spacing of the plurality of front rows of cutting teeth in the core tooth group projected on the radial crown profile of the PDC drill bit is a core tooth arrangement spacing J1, the spacing of the plurality of front rows of cutting teeth in the shoulder tooth group projected on the radial crown profile of the PDC drill bit is a shoulder tooth arrangement spacing J2, and there is a relationship of 1.5J2≤J1≤2J2.

2. The PDC drill bit according to claim 1, wherein the shoulder tooth arrangement spacing J2 is 3mm-4mm.

3. The PDC drill bit according to claim 1, wherein the PDC drill bit further comprises a gauge portion connected to the shoulder portion, and a plurality of rear rows of cutting teeth are arranged in the gauge portion to form a gauge tooth group; the tooth arrangement density of the shoulder tooth group is less than the tooth arrangement density of the gauge tooth group.

4. The PDC drill bit according to claim 3, wherein the spacing of the plurality of front rows of cutting teeth in the gauge tooth group projected on the radial crown profile of the PDC drill bit is a gauge tooth arrangement spacing J3, and the gauge tooth arrangement spacing J3 is 2mm-3mm.

5. The PDC drill bit according to any one of claims 1-4, wherein the PDC drill bit further comprises a plurality of rear rows of cutting teeth, and the plurality of rear rows of cutting teeth are arranged on the plurality of blades in one-to-one correspondence with at least a part of the plurality of front rows of cutting teeth, and the arrangement radius of the corresponding front row of cutting teeth and the rear row of cutting teeth is the same.

6. The PDC drill bit according to claim 5, wherein the distribution angle of the corresponding front row of cutting teeth and the rear row of cutting teeth in the circumferential direction of the PDC drill bit is different by 120°-200°.

7. The PDC drill bit according to claim 6, wherein The distribution angle of the corresponding front row of cutting teeth and the rear row of cutting teeth in the circumference of the PDC drill bit is 180°±10°.

8. The PDC drill bit of claim 5, wherein, The height of the front row of cutting teeth is higher than the height of the corresponding rear row of cutting teeth.

9. The PDC drill bit of claim 5, wherein, The height difference between the corresponding front row of cutting teeth and the rear row of cutting teeth is greater than 0 and does not exceed 1.5 mm.

10. The PDC drill bit of claim 1, wherein, The number of the blades is more than 6.

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