Multi-groove diamond composite pieces and anchor drill bits, coreless drill bits, coring drill bits

Abstract

The present invention relates to a multi-groove diamond composite sheet and an anchor drill bit, a coreless drill bit and a coring drill bit. The diamond composite sheet comprises a cemented carbide substrate and a diamond layer. The diamond layer is sintered on the cemented carbide substrate by high temperature and high pressure. The bottom end face of the diamond layer is a plane combined with the cemented carbide layer. The cutting end face of the diamond layer is a truncated cone-shaped drum-shaped surface. A plurality of adjacently distributed dividing grooves are arranged on the edge of the cutting end face of the diamond layer. Cutting edges are formed between adjacent dividing grooves. The edge of the diamond layer of the present invention is provided with dividing grooves so that the edge of the diamond forms a plurality of serrated cutting edges. These dividing grooves prevent cracks from expanding in the entire diamond layer. When subjected to impacts of the same magnitude, the falling area of ​​the diamond layer is greatly reduced, which greatly increases the service life of the diamond composite sheet. At the same time, the cutting edges between the dividing grooves release the internal stress in the diamond layer, thereby preventing the diamond layer from being delaminated from the substrate.

Description

Technical Field

[0001] The invention relates to the technical field of mining drill bits, and in particular to a multi-groove diamond composite sheet and an anchor drill bit, a coreless drill bit, and a coring drill bit. Background Art

[0002] Diamond composite sheet is a composite material synthesized by diamond layer and cemented carbide matrix under high temperature and high pressure conditions. The diamond layer has the characteristics of high hardness and good wear resistance, while cemented carbide improves the flexibility and weldability of the composite material as a whole. This material is widely used in the manufacture of cutting teeth for petroleum geological drill bits. Since the cemented carbide always wears before the diamond layer when used underground, the diamond cemented carbide composite sheet always maintains good self-sharpening properties, and a high mechanical drilling speed can be obtained by applying very low drilling pressure. However, during use, due to the influence of complex geological conditions on the diamond cemented carbide composite sheet, the diamond cemented carbide composite sheet sometimes cracks, greatly reducing the service life of the composite sheet. This cracking may occur in the cemented carbide layer or the interface between the cemented carbide layer and the diamond layer, or it may occur in the diamond layer. The cracking of the cemented carbide layer can be solved by increasing the toughness of the cemented carbide. The cracking problem of the interface between the cemented carbide layer and the diamond layer is mainly caused by the large difference in thermal expansion coefficients between the cemented carbide and the diamond, the existence of large internal stress, and the low bonding force between the cemented carbide layer and the diamond layer. The solution includes cutting grooves on the cemented carbide layer to increase the bonding force with the diamond layer and adjusting the thickness ratio of the cemented carbide layer to the diamond layer. The rupture of the diamond layer starts with microcracks. During the excavation process of the drill bit, due to changes in the geological structure, the excavation surface of the diamond layer will continue to be subjected to unbalanced impact force, which will cause tiny cracks in the diamond layer, especially at the boundary of the diamond layer. These cracks will continue to expand until they penetrate the entire diamond layer, or the cracks extend to the surface of the diamond layer or the cemented carbide layer, causing a large area of ​​the diamond layer or the diamond layer connected to the cemented carbide layer to fall off from the diamond-carbide composite sheet, making it invalid. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a multi-groove diamond composite sheet and an anchor drill bit, a coreless drill bit, and a coring drill bit.

[0004] The specific contents are as follows: A multi-groove diamond composite sheet includes a cemented carbide substrate and a diamond layer, wherein the diamond layer is sintered on the cemented carbide substrate by high temperature and high pressure, the bottom end face of the diamond layer is a plane combined with the cemented carbide layer, the cutting end face of the diamond layer is a truncated cone-shaped drum-shaped surface, and a plurality of adjacently distributed dividing grooves are provided on the edge of the cutting end face of the diamond layer, and a cutting edge is formed between adjacent dividing grooves, and the central angle corresponding to the cutting edge is α, and α≥20°.

[0005] Preferably, the separation groove is a sloped rectangular groove or trapezoidal groove cut radially inward from the circumferential surface of the diamond layer, and the width of the rectangular groove or trapezoidal groove formed on the circumferential surface of the diamond layer is L, and L≥0.5mm, and the angle between the slope surface of the rectangular groove or trapezoidal groove and the bottom end surface of the diamond layer is β, and β≤60°.

[0006] Preferably, the separation groove is a rectangular groove or a trapezoidal groove that is cut radially inward from the circumferential surface of the diamond layer to form a sloped shape, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is M, and M≥0.5mm, and the angle between the slope surface of the rectangular groove or the trapezoidal groove and the bottom end surface of the diamond layer is δ, and δ≤60°.

[0007] Preferably, the separation groove is a rectangular groove or a trapezoidal groove formed by cutting upward from the bottom end surface of the diamond layer, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is N, and N≥0.5mm, and the depth of the rectangular groove or the trapezoidal groove is H, and H≥1mm.

[0008] Preferably, it includes an integrally formed drill shank portion and a drill base portion, the drill base portion is arranged on the upper part of the drill shank portion, the drill base portion includes at least two wings arranged in a spiral around the axis, and a multi-groove diamond composite sheet or a toothless diamond composite sheet is installed on the upper end of the wing body; a chip groove portion is provided at the position where the lower part of the wing body is connected to the drill shank portion, the chip groove portion includes a chip groove A and a chip groove B, both of which are arc-shaped, the chip groove A spirally extends downward from the lower part of the wing body at the front end of the multi-groove diamond composite sheet or the toothless diamond composite sheet, and the chip groove B spirally extends downward from the tail of the chip groove A; a water channel is provided inside the anchor drill bit, which passes through the drill shank portion, the chip groove portion and the center of the drill base portion, and a connecting thread is provided in the water channel; the opening of the water channel between the wings is a square opening or a circular opening.

[0009] Preferably, the upper ends of the wing bodies are all installed with multi-grooved diamond composite sheets; or, multi-grooved diamond composite sheets and toothless diamond composite sheets are installed at intervals on the upper ends of the wing bodies.

[0010] Preferably, it comprises an integrally connected handle and a plurality of wings, the interior of the handle being a hollow structure, a mounting thread being provided in the tail of the handle, a plurality of wings surrounding the front end of the handle, a main feed composite sheet and a hole expansion composite sheet being provided on each wing, the hole expansion composite sheet being located at the outer edge of the wing, the main feed composite sheet being located at the inner side of the hole expansion composite sheet, a flushing hole communicating with the interior of the handle being provided on the front end surface of the handle, at least two hole expansion composite sheets being arranged on the same circumference front and back; a raised auxiliary wing being provided on the front end surface of the handle between the flushing holes, and an auxiliary composite sheet being provided on the auxiliary wing; an auxiliary flushing hole being provided on the upper end side surface of the handle located between the wings; the main feed composite sheet being a multi-groove diamond composite sheet or a toothless diamond composite sheet, the hole expansion composite sheet being a multi-groove diamond composite sheet or a toothless diamond composite sheet, and the auxiliary composite sheet being a multi-groove diamond composite sheet or a toothless diamond composite sheet.

[0011] Preferably, the main feed composite sheets are all multi-groove diamond composite sheets, the hole expansion composite sheets are all multi-groove diamond composite sheets, and the auxiliary composite sheets are all multi-groove diamond composite sheets; or, a part of the main feed composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the hole expansion composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the auxiliary composite sheets on the auxiliary wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

[0012] Preferably, it comprises an integrally connected handle and a plurality of wings, a core sampling hole is provided in the middle of the handle, a mounting thread is provided at the tail of the handle, a plurality of wings surround the front end of the handle, a main feed composite sheet and a hole expansion composite sheet are provided on the wings, the hole expansion composite sheet is located at the outer edge of the wing, the main feed composite sheet is located on the inner side of the hole expansion composite sheet, there are at least two hole expansion composite sheets, which are arranged on the same circumference front and back; the main feed composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet, and the hole expansion composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet.

[0013] Preferably, the main feed composite sheets are all multi-groove diamond composite sheets, and the hole expansion composite sheets are all multi-groove diamond composite sheets; or, a part of the main feed composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the hole expansion composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

[0014] Beneficial technical effects of the present invention: The present invention is a multi-groove diamond composite sheet and an anchor drill bit, a coreless drill bit, and a coring drill bit. The diamond composite sheet includes a cemented carbide substrate and a diamond layer. The edge of the diamond layer of the present invention is provided with a separation groove, so that the edge of the diamond forms a plurality of serrated cutting edges. These separation grooves prevent the cracks from extending throughout the diamond layer. When subjected to the same magnitude of impact, the diamond layer shedding area is greatly reduced, which greatly increases the service life of the diamond composite sheet. At the same time, the cutting edges between the separation grooves release the internal stress in the diamond layer to prevent the diamond layer from being delaminated from the substrate; the serrated cutting edges formed by the separation grooves can reduce the contact area between the cutting end and the circumferential surface of the multi-groove diamond composite sheet and the formation, thereby increasing the bit's penetration capacity; by designing the cutting end face to be a drum-shaped surface larger than the bottom end face area, the entire composite sheet becomes an irregular cylindrical anisotropic structure, thereby reducing the friction between the rear of the circumferential surface of the composite sheet substrate and the formation, which can increase the mechanical drilling speed of the drill bit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the three-dimensional structure of a multi-groove diamond composite sheet (the separation grooves are radial slope-type rectangular grooves);

[0016] Figure 2 yes Figure 1 A top view of

[0017] Figure 3 yes Figure 2 Sectional view of AA in the middle;

[0018] Figure 4 It is a schematic diagram of the three-dimensional structure of a multi-groove diamond composite sheet (the separation grooves are non-radial slope-type rectangular grooves);

[0019] Figure 5 yes Figure 4 A top view of

[0020] Figure 6 yes Figure 5 Cross-sectional view of the middle BB;

[0021] Figure 7 It is a schematic diagram of the three-dimensional structure of a multi-groove diamond composite sheet (the separation grooves are vertically penetrating trapezoidal grooves);

[0022] Figure 8 yes Figure 7 A top view of

[0023] Fig. 9 yes Figure 8 Cross-sectional view of the middle BB;

[0024] FIG10 is a front view of a structure of an anchor drill bit;

[0025] Figure 11 is Fig.10 Left view of;

[0026] Figure 12 is Fig.10 A top view of

[0027] FIG13 is a top view of another structure of an anchor drill bit;

[0028] FIG14 is a front view of a structure of a coreless drill bit;

[0029] Fig.15 yes Fig.14 A top view of

[0030] FIG16 is a top view of another structure of a coreless drill bit;

[0031] FIG17 is a front view of a structure of a coring drill bit;

[0032] Figure 18 is Fig.17 A top view of

[0033] FIG19 is a top view of another structure of a coring drill bit;

[0034] In the figure: Figure 1-Figure 9 In the figure, 11. diamond layer, 12. cemented carbide substrate, 111. cutting edge, 13. a sloped rectangular groove formed by cutting inwardly along the radial direction, 14. a cutting end face of the diamond layer, 15. a bottom end face of the diamond layer, 16. a sloped trapezoidal groove formed by cutting inwardly away from the radial direction, 17. a trapezoidal groove formed by cutting upwardly from the bottom end face of the diamond layer.

[0035] Figure 10-13 Among them, 18. drill shank, 19. chip groove, 20. drill base, 21. water channel, 22. connecting thread, 23. chip groove B, 24. chip groove A, 25. rectangular flat hole, 26. wing body, 27. diamond composite sheet.

[0036] Figure 14-16 Among them, 28. handle, 29. wing, 30. main feed composite sheet, 31. hole expansion composite sheet, 32. flushing hole, 33. auxiliary flushing hole, 34. auxiliary wing, 35. auxiliary composite sheet.

[0037] Figure 17-Figure 19 In the figure, 36. handle, 37. wing, 38. main feed composite sheet, 39. hole expansion composite sheet, 40. core hole, 41. installation thread. DETAILED DESCRIPTION

[0038] Example 1: See Figure 1-9The multi-groove diamond composite sheet comprises a cemented carbide substrate and a diamond layer, wherein the diamond layer is sintered on the cemented carbide substrate by high temperature and high pressure, the bottom end face of the diamond layer is a plane combined with the cemented carbide layer, the cutting end face of the diamond layer is a truncated cone-shaped drum-shaped surface, and a plurality of adjacently distributed dividing grooves are arranged on the edge of the cutting end face of the diamond layer, and a cutting edge is formed between adjacent dividing grooves, and the central angle corresponding to the cutting edge is α, and α≥20°.

[0039] The separation groove is a rectangular groove or a trapezoidal groove cut radially inward from the circumferential surface of the diamond layer to form a sloped rectangular groove or a trapezoidal groove, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is L, and L ≥ 0.5mm, and the angle between the slope surface of the rectangular groove or the trapezoidal groove and the bottom end surface of the diamond layer is β, and β ≤ 60°. In this embodiment Figure 1 - 3 is a schematic diagram showing that the separation groove is a sloped rectangular groove cut radially inward from the circumferential surface of the diamond layer;

[0040] The separation groove is a rectangular groove or a trapezoidal groove that is cut away radially inward from the circumferential surface of the diamond layer to form a sloped rectangular groove or a trapezoidal groove, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is M, and M ≥ 0.5 mm, and the angle between the slope surface of the rectangular groove or the trapezoidal groove and the bottom end surface of the diamond layer is δ, and δ ≤ 60°. In this embodiment Figure 4-6 A schematic diagram is given of a separation groove which is a sloped rectangular groove cut radially inward from the circumferential surface of the diamond layer;

[0041] The separation groove is a rectangular groove or a trapezoidal groove formed by cutting upward from the bottom end surface of the diamond layer, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is N, and N ≥ 0.5mm, and the depth of the rectangular groove or the trapezoidal groove is H, and H ≥ 1mm. Figure 7-9 A schematic diagram of a separation groove being a trapezoidal groove formed by cutting upward from the bottom end surface of the diamond layer is given;

[0042] The edge of the diamond layer of the present invention is provided with separation grooves, so that the edge of the diamond forms a plurality of serrated cutting edges, and these separation grooves prevent the cracks from expanding in the entire diamond layer. When subjected to the same magnitude of impact, the falling area of ​​the diamond layer is greatly reduced, which greatly increases the service life of the diamond composite sheet. At the same time, the cutting edges between the separation grooves release the internal stress in the diamond layer, and prevent the diamond layer and the matrix from being delaminated; the serrated cutting edges formed by the separation grooves can reduce the contact area between the cutting end and the circumferential surface of the multi-groove diamond composite sheet and the formation, and increase the penetration capacity of the drill bit; by designing the cutting end face to be a drum-shaped surface larger than the bottom end face area, the entire composite sheet becomes an irregular cylindrical anisotropic structure, thereby reducing the friction between the rear part of the circumferential surface of the composite sheet matrix and the formation, and can improve the mechanical drilling speed of the drill bit.

[0043] Example 2: See Figure 10-12 , an anchor drill bit using the multi-groove diamond composite sheet described in Example 1, comprising an integrally formed drill shank and a drill base, the drill base being arranged on the upper part of the drill shank, the drill base comprising at least two wings arranged in a spiral around the axis, a diamond composite sheet being mounted on the upper end of the wing; a chip groove is provided at the lower part of the wing connected to the drill shank, the chip groove comprises an arc-shaped chip groove A and a chip groove B, the chip groove A spirally extends downward from the lower part of the wing at the front end of the diamond composite sheet, and the chip groove B spirally extends downward from the tail of the chip groove A; a water channel is provided inside the anchor drill bit, which passes through the drill shank, the chip groove and the center of the drill base, and a connecting thread is provided in the water channel; the opening of the water channel between the wings is a circular opening. The diamond composite sheets are all multi-groove diamond composite sheets.

[0044] Example 3: See Fig.13 , Embodiment 3 is basically the same as Embodiment 2, and the similarities are not repeated here. The difference is that the diamond composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet, and the multi-groove diamond composite sheet and the toothless diamond composite sheet are installed at the upper end of the wing body in an intermittent distribution.

[0045] Example 4: See Figure 14-15A coreless drill bit using the multi-groove diamond composite sheet described in Example 1 comprises an integrally connected handle and a plurality of wings, the interior of the handle is a hollow structure, a mounting thread is provided in the tail of the handle, and a plurality of wings surround the front end of the handle, each wing is provided with a main feed composite sheet and a hole expansion composite sheet, the hole expansion composite sheet is located at the outer edge of the wing, the main feed composite sheet is located on the inner side of the hole expansion composite sheet, a flushing hole connected to the interior of the handle is provided on the front end surface of the handle, and there are at least two hole expansion composite sheets, which are arranged on the same circumference front and back; a raised auxiliary wing is provided on the front end surface of the handle between the flushing holes, and an auxiliary composite sheet is provided on the auxiliary wing; an auxiliary flushing hole is provided on the upper end side surface of the handle located between the wings; the main feed composite sheet, the hole expansion composite sheet and the auxiliary composite sheet are all multi-groove diamond composite sheets.

[0046] Example 5: See Fig.16 , Embodiment 5 is basically the same as Embodiment 4, and the similarities are not repeated here. The differences are as follows: a portion of the main feed composite sheets on several wings are multi-grooved diamond composite sheets, and another portion are toothless diamond composite sheets, and the multi-grooved diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a portion of the hole expansion composite sheets on several wings are multi-grooved diamond composite sheets, and another portion are toothless diamond composite sheets, and the multi-grooved diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a portion of the auxiliary composite sheets on the auxiliary wings are multi-grooved diamond composite sheets, and another portion are toothless diamond composite sheets, and the multi-grooved diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

[0047] Example 6: See Figure 17-18 A core drilling drill bit using the multi-groove diamond composite sheet described in Example 1 includes an integral shank and a plurality of wings, a core drilling hole is provided in the middle of the shank, a mounting thread is provided at the tail of the shank, a plurality of wings surround the front end of the shank, a main feed composite sheet and a hole expansion composite sheet are provided on the wings, the hole expansion composite sheet is located at the outer edge of the wing, the main feed composite sheet is located on the inner side of the hole expansion composite sheet, there are at least two hole expansion composite sheets, and the front and rear are arranged on the same circumference; the main feed composite sheet and the hole expansion composite sheet are both multi-groove diamond composite sheets.

[0048] Example 7: See Fig.19 , Embodiment 7 is basically the same as Embodiment 6, and the similarities are not repeated here. The difference is that: a part of the main feeding composite sheets on several wings are multi-grooved diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-grooved diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the hole expansion composite sheets on several wings are multi-grooved diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-grooved diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

Claims

1. A multi-groove diamond composite sheet, comprising a cemented carbide substrate and a diamond layer, characterized in that: The diamond layer is sintered on the cemented carbide substrate at high temperature and high pressure, the bottom end surface of the diamond layer is a plane combined with the cemented carbide layer, the cutting end surface of the diamond layer is a truncated cone-shaped drum surface, and a plurality of adjacently distributed separation grooves are provided on the edge of the cutting end surface of the diamond layer, and a cutting edge is formed between adjacent separation grooves, and the central angle corresponding to the cutting edge is α, and α≥20°; The separation groove is a rectangular groove or a trapezoidal groove that is cut radially inward from the circumferential surface of the diamond layer to form a sloped shape, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is M, and M≥0.5mm, and the angle between the slope surface of the rectangular groove or the trapezoidal groove and the bottom end surface of the diamond layer is δ, and δ≤60°.

2. A multi-groove diamond composite sheet, comprising a cemented carbide substrate and a diamond layer, characterized in that: The diamond layer is sintered on the cemented carbide substrate at high temperature and high pressure, the bottom end surface of the diamond layer is a plane combined with the cemented carbide layer, the cutting end surface of the diamond layer is a truncated cone-shaped drum surface, and a plurality of adjacently distributed separation grooves are provided on the edge of the cutting end surface of the diamond layer, and a cutting edge is formed between adjacent separation grooves, and the central angle corresponding to the cutting edge is α, and α≥20°; The separation groove is a sloped rectangular groove or trapezoidal groove formed by cutting radially inward from the circumferential surface of the diamond layer, and the width of the rectangular groove or trapezoidal groove formed on the circumferential surface of the diamond layer is L, and L≥0.5mm, and the angle between the slope surface of the rectangular groove or trapezoidal groove and the bottom end surface of the diamond layer is β, and β≤60°.

3. A multi-groove diamond composite sheet, comprising a cemented carbide substrate and a diamond layer, characterized in that: The diamond layer is sintered on the cemented carbide substrate at high temperature and high pressure, the bottom end surface of the diamond layer is a plane combined with the cemented carbide layer, the cutting end surface of the diamond layer is a truncated cone-shaped drum surface, and a plurality of adjacently distributed separation grooves are provided on the edge of the cutting end surface of the diamond layer, and a cutting edge is formed between adjacent separation grooves, and the central angle corresponding to the cutting edge is α, and α≥20°; The separation groove is a rectangular groove or a trapezoidal groove formed by cutting upward from the bottom end surface of the diamond layer, and the width of the rectangular groove or the trapezoidal groove formed on the circumferential surface of the diamond layer is N, and N≥0.5mm, and the depth of the rectangular groove or the trapezoidal groove is H, and H≥1mm.

4. An anchor drill bit using the multi-groove diamond composite sheet according to claim 1, characterized in that: The invention comprises an integrally formed drill shank portion and a drill base portion, wherein the drill base portion is arranged on the upper part of the drill shank portion, and the drill base portion comprises at least two wings arranged in a spiral around an axis, and a multi-groove diamond composite sheet or a toothless diamond composite sheet is installed on the upper end of the wing body; a chip groove portion is provided at the position where the lower part of the wing body is connected to the drill shank portion, and the chip groove portion comprises an arc-shaped chip groove A and a chip groove B, wherein the chip groove A spirally extends downward from the lower part of the wing body at the front end of the multi-groove diamond composite sheet or the toothless diamond composite sheet, and the chip groove B spirally extends downward from the tail of the chip groove A; a water channel is provided inside the anchor drill bit, which passes through the drill shank portion, the chip groove portion and the center of the drill base portion, and a connecting thread is provided inside the water channel; the opening of the water channel between the wings is a square opening or a circular opening.

5. The anchor drill bit according to claim 4, characterized in that: The upper end of the wing body is installed with a multi-groove diamond composite sheet; or, the multi-groove diamond composite sheet and the toothless diamond composite sheet are installed at intervals on the upper end of the wing body.

6. A coreless drill bit using the multi-groove diamond composite sheet according to claim 1, characterized in that: It comprises a handle and a plurality of wings connected together. The interior of the handle is a hollow structure. The tail of the handle is provided with a mounting thread. The plurality of wings surround the front end of the handle. Each wing is provided with a main feed composite sheet and a hole expansion composite sheet. The hole expansion composite sheet is located at the outer edge of the wing, and the main feed composite sheet is located on the inner side of the hole expansion composite sheet. A flushing hole connected to the interior of the handle is provided on the front end surface of the handle. There are at least two hole expansion composite sheets, which are arranged on the same circumference front and back. A raised auxiliary wing is provided on the front end surface of the handle between the flushing holes, and an auxiliary composite sheet is provided on the auxiliary wing. An auxiliary flushing hole is provided on the upper end side surface of the handle located between the wings. The main feed composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet, the hole expansion composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet, and the auxiliary composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet.

7. The coreless drill bit according to claim 6, characterized in that: The main feed composite sheets are all multi-groove diamond composite sheets, the hole expansion composite sheets are all multi-groove diamond composite sheets, and the auxiliary composite sheets are all multi-groove diamond composite sheets; or, a part of the main feed composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the hole expansion composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the auxiliary composite sheets on the auxiliary wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

8. A core drill bit using the multi-groove diamond composite sheet according to claim 1, characterized in that: It comprises an integrally connected handle and a plurality of wings, wherein a core sampling hole is provided in the middle of the handle, a mounting thread is provided at the tail of the handle, and a plurality of wings surround the front end of the handle, a main feed composite sheet and a hole expansion composite sheet are provided on the wings, the hole expansion composite sheet is located at the outer edge of the wing, the main feed composite sheet is located at the inner side of the hole expansion composite sheet, there are at least two hole expansion composite sheets, which are arranged on the same circumference front and back; the main feed composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet, and the hole expansion composite sheet is a multi-groove diamond composite sheet or a toothless diamond composite sheet.

9. The coring drill bit according to claim 8, characterized in that: The main feed composite sheets are all multi-groove diamond composite sheets, and the hole expansion composite sheets are all multi-groove diamond composite sheets; or, a part of the main feed composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals; a part of the hole expansion composite sheets on several wings are multi-groove diamond composite sheets, and the other part are toothless diamond composite sheets, and the multi-groove diamond composite sheets and the toothless diamond composite sheets are distributed at intervals.

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