Tool bit for diamond thin-wall drill bit and preparation method and application of tool bit

Abstract

The invention discloses a tool bit for a diamond thin-wall drill bit and a preparation method and application thereof.The tool bit comprises a tool bit body, three straight-groove corrugated grooves are formed in the surface of the outer side of the tool bit body at intervals, two straight-groove corrugated grooves are formed in the surface of the inner side of the tool bit body at intervals, and three V-shaped grooves are formed in the surface of the top of the tool bit body at intervals; the invention further discloses a preparation method of the tool bit, the tool bit adopts a powder metallurgy process, the tool bit is formed by uniformly mixing a metal powder mixture and diamond particles through hot pressing sintering, and the tool bit is welded to a machined diamond base body to form the diamond thin-wall drill bit. According to the structural design of the tool bit, the contact area between the side face of the tool bit and a drilling and cutting material is reduced, the chip removal and cooling capacity is improved, the contact area between the tool bit and the drilling and cutting material is reduced, the drill bit can rapidly drill the drilled and cut material, the sharpness of the drill bit is improved, and the rapid drilling purpose is achieved.

Description

Technical Field

[0001] The invention relates to the field of diamond drill bits, and in particular to a cutter head for a diamond thin-wall drill bit and a preparation method and application thereof. Background Art

[0002] Conventional diamond drill bits connect the cutter head and steel base together through laser or high-frequency welding. The drilling environment has a great impact on the performance of the drill bit. Generally, in a wet drilling environment with coolant, the shape of the drill bit is not required. However, in drilling and cutting conditions without coolant, the chip removal and cooling capabilities of the drill bit itself are very important. If the heat generated by drilling and cutting cannot be dissipated in time, and the rock chips cannot be discharged in time, the entire cutter head will turn black due to high temperature, and the diamond will decrease in strength and break due to ablation, resulting in the drill bit being unable to perform drilling and cutting effectively. Therefore, the material and shape of the drill bit are very important. They can discharge heat and rock chips in time, thereby improving the drillability of the drill bit, and ensure the strength of the cutter head and increase its service life. Summary of the invention

[0003] The purpose of the present invention is to provide a cutter head for a diamond thin-wall drill bit to solve the problem in the prior art that under drilling and cutting conditions without coolant, the drill bit's own chip removal and cooling capabilities are insufficient, which easily leads to a decrease in cutter head performance, thereby reducing the drill bit's drilling and cutting performance.

[0004] In order to solve the above technical problems, the present invention is implemented by the following technical solutions:

[0005] A cutter head for a diamond thin-wall drill bit comprises a cutter head body, wherein the outer surface of the cutter head body is provided with three straight corrugated grooves at intervals, and the raw materials of the cutter head body comprise a metal powder mixture and diamond particles, wherein the volume fraction of the diamond particles is 30%-50%, and the particle size is 400-600 μm, and the metal powder mixture comprises the following raw materials in weight percentage: 40%-60% of nano cobalt powder, 20%-30% of atomized copper tin powder, 5%-15% of nano nickel powder, and 5%-15% of cast carbide powder.

[0006] Preferably, two straight corrugated grooves are arranged at intervals on the inner surface of the cutter head body.

[0007] Preferably, three V-shaped grooves are arranged at intervals on the top surface of the cutter head body.

[0008] Preferably, the straight groove corrugated groove structures on the inner and outer sides of the cutter head body are the same, and the bottom width of the straight groove corrugated groove is 0.5mm-3mm, the top width is 1mm-5mm, and the depth is 0.5mm-1.5mm.

[0009] Preferably, the straight-groove corrugated grooves on the outer and inner sides of the cutter head body are cross-arranged.

[0010] Preferably, the depth of the V-shaped groove is 0.5mm-3mm, and the top width is 2mm-5mm.

[0011] A method for preparing a cutter head for a diamond thin-wall drill bit, specifically comprising the following preparation steps:

[0012] (1) Ingredients: Weigh the following raw materials in the following weight proportions: 40-60 parts of nano cobalt powder, 20-30 parts of atomized copper tin powder, 5-15 parts of nano nickel powder, 5-15 parts of casting carbide powder, and 30%-50% by volume of diamond particles (based on 400%), and mix the above raw materials to obtain alloy matrix powder;

[0013] (2) Mixing: Put the alloy matrix powder obtained in step (1) into a mixer, add steel balls and dry mix for 1 hour, then add alcohol and mix for 1 hour;

[0014] (3) Granulation: Add 30 g / kg of granulating agent to the powder mixed in step (2) above, and add 800 ml / kg of isopropanol at the same time, stirring continuously during the addition process, and after stirring evenly, pass through a 20# sieve, and then put it into an oven for baking at a temperature of 100°C for a baking time of 1 hour. Finally, pour the dried powder into a 30# sieve and sieve to disperse the lumps;

[0015] (4) Cold pressing: cold pressing the powder granulated in step (3) into a cold pressed blank according to the weight required by the cutter head;

[0016] (5) Hot pressing and sintering: the cutter head after cold pressing in the above step (4) is placed in a graphite mold for hot pressing and sintering, the sintering temperature is 850-920°C, the pressure is 35Mpa, and the holding time is 300S;

[0017] (6) Subsequent processing: The cutter head sintered in the above step (5) is deburred, and the curvature of the welding surface is ground, sharpened, and polished to finally obtain a cutter head with the required curvature.

[0018] A diamond thin-wall drill bit comprises a cutter head and a diamond matrix, wherein the cutter head is welded to the diamond matrix.

[0019] The present invention has the following beneficial effects:

[0020] (1) The cutter head of the present invention has a simple structure. By designing straight groove corrugated grooves on both the inner and outer surfaces of the cutter head body, the contact area between the side of the cutter head and the drilled material is reduced, thereby increasing the chip removal and cooling capabilities. At the same time, by designing a V-shaped groove on the top of the cutter head, the contact area with the drilled material is reduced, which is conducive to the drill bit quickly drilling into the drilled material, improving the sharpness of the drill bit, and achieving the purpose of rapid drilling;

[0021] (2) The cutter head of the present invention adopts a powder metallurgy process. The cutter head is formed by evenly mixing a metal powder mixture and diamond particles and then hot pressing and sintering. The substrate is welded to the cutter head after mechanical processing. By adjusting the ratio of various raw materials and working together, the strength of the cutter head can be effectively improved, thereby improving the drilling and cutting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the outer side of the cutter head body in the present invention;

[0023] Figure 2 It is a structural schematic diagram of the inner side of the cutter head body in the present invention.

[0024] In the figure: 1-cutter body; 101-straight groove corrugated groove; 102-V-shaped groove. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 1-2 As shown, a cutter head for a diamond thin-wall drill bit comprises a cutter head body 1, the outer surface of the cutter head body 1 is provided with three straight groove corrugated grooves 101 at intervals, the inner surface of the cutter head body 1 is provided with two straight groove corrugated grooves 101 at intervals, and the top surface of the cutter head body 1 is provided with three V-shaped grooves 102 at intervals. The raw materials of the cutter head body 1 comprise a metal powder mixture and diamond particles, wherein the volume fraction of the diamond particles is 30%-50%, and the particle size is 400-600 μm, and the metal powder mixture comprises the following raw materials in weight percentage: 40%-60% of nano cobalt powder, 20%-30% of atomized copper tin powder, 5%-15% of nano nickel powder, and 5%-15% of cast carbide powder.

[0027] The cutter head of the present invention has a simple structure. Through the design of the straight groove corrugated groove 101 on the inner and outer sides of the cutter head body 1 and the V-shaped groove 102 on the top, the friction area between the side and top of the cutter head and the drilled material can be effectively reduced, thereby reducing the resistance of the material to the drill bit during the cutting process; it is also beneficial to the discharge of rock chips during the drilling and cutting process, and better drainage; the V-shaped groove 102 on the top of the cutter head not only reduces the contact area with the cutting material, but also facilitates the drill bit to quickly drill into the drilled material, greatly improves the cutting speed of the drill bit, and can also increase the service life of the cutter head to a certain extent.

[0028] Furthermore, the straight groove corrugated groove 101 on the inner and outer sides of the cutter head body 1 has the same structure, the bottom width of the straight groove corrugated groove 101 is 0.5mm-3mm, the top width is 1mm-5mm, the depth is 0.5mm-1.5mm, the depth of the V-shaped groove 102 is 0.5mm-3mm, and the top width is 2mm-5mm.

[0029] Specifically, the straight groove corrugated groove 101 on the inner and outer sides of the cutter head body 1 has the same structure, the bottom width of the straight groove corrugated groove 101 is 0.5mm-3mm, the top width is 1mm-5mm, the depth is 0.5mm-1.5mm, and the depth of the V-shaped groove 102 is 0.5mm-3mm, and the top width is 2mm-5mm. The straight groove corrugated groove 101 and the V-shaped groove 102 of the above-mentioned size structure can make the chip removal and drilling and cutting effects of the cutter head better without affecting the performance strength of the cutter head itself.

[0030] Specifically, the straight groove corrugated grooves 101 on the outer side and the inner side of the cutter body 1 are arranged crosswise. The above design, staggering the straight groove corrugated grooves 101 on the inner and outer sides, can ensure the performance strength of the cutter head, and can also reduce the friction area between the cutter head and the drilled material to a greater extent, and improve the chip removal effect.

[0031] The following is a further detailed description taking the application of the cutter head to a diamond thin-wall drill bit as an example.

[0032] Example 1

[0033] A diamond thin-wall drill bit comprises a cutter head and a diamond matrix. The raw materials of the cutter head comprise a metal powder mixture and diamond particles, wherein the volume fraction of the diamond particles is 30%-50% and the particle size is 400-600 μm. The metal powder mixture comprises the following raw materials in weight percentage: 40%-60% of nano cobalt powder, 20%-30% of atomized copper tin powder, 5%-15% of nano nickel powder and 5%-15% of cast carbide powder. The preparation steps are as follows:

[0034] (1) Ingredients: Weigh the following raw materials in the following weight proportions: 55 parts of nano cobalt powder, 25 parts of atomized copper tin powder, 10 parts of nano nickel powder, 10 parts of casting carbide powder, 40% by volume of diamond particles (based on 400%), and a particle size of 500 μm, and mix the above raw materials to obtain alloy matrix powder;

[0035] (2) Mixing: Put the alloy matrix powder obtained in step (1) into a mixer, add steel balls and dry mix for 1 hour, then add alcohol and mix for 1 hour;

[0036] (3) Granulation: Add 30 g / kg of granulating agent to the powder mixed in step (2) above, and add 800 ml / kg of isopropanol at the same time, stirring continuously during the addition process, and after stirring evenly, pass through a 20# sieve, and then put it into an oven for baking at a temperature of 100°C for a baking time of 1 hour. Finally, pour the dried powder into a 30# sieve and sieve to disperse the lumps;

[0037] (4) Cold pressing: cold pressing the powder granulated in step (3) into a cold pressed blank according to the weight required by the cutter head;

[0038] (5) Hot pressing and sintering: the cutter head after cold pressing in the above step (4) is placed in a graphite mold for hot pressing and sintering, the sintering temperature is 850-920°C, the pressure is 35Mpa, and the holding time is 300S;

[0039] (6) Subsequent processing: Deburring the cutter head sintered in step (5) above, and grinding the curvature of the welding surface, to finally obtain a cutter head with the required curvature;

[0040] (7) Laser welding: Use a 3.0KW optical fiber laser welding machine to weld the cutter head to the diamond substrate at a welding speed of 15-20mm / s;

[0041] (8) Finally, proceed with subsequent sharpening, polishing, and warehousing.

[0042] Example 2

[0043] This embodiment is the same as embodiment 1, except that 60 parts of nano cobalt powder, 20 parts of atomized copper tin powder, 15 parts of nano nickel powder, and 5 parts of cast carbide powder are weighed, the volume fraction of diamond particles is 30% (based on 400%), and the particle size is 400 μm.

[0044] Example 3

[0045] This embodiment is the same as embodiment 1, except that 40 parts of nano cobalt powder, 30 parts of atomized copper tin powder, 15 parts of nano nickel powder, and 15 parts of cast carbide powder are weighed, the volume fraction of diamond particles is 50% (based on 400%), and the particle size is 550 μm.

[0046] Example 4

[0047] This embodiment is the same as embodiment 1, except that 52 parts of nano cobalt powder, 28 parts of atomized copper tin powder, 5 parts of nano nickel powder, and 15 parts of cast carbide powder are weighed, the volume fraction of diamond particles is 35% (based on 400%), and the particle size is 600 μm.

[0048] The diamond thin-wall drill bits prepared in Examples 1-4 are made using a powder metallurgy process. The cutter heads are formed by evenly mixing a metal powder mixture and diamond particles and then hot pressing and sintering. The substrate is welded to the cutter head after machining. The only difference in the weight percentage of the raw materials of the cutter heads in each embodiment is that the diamond thin-wall drill bits formed therefrom are tested for various properties, and it is found that the differences in the properties are not large. By adjusting the ratio of various raw materials and working together, the strength of the cutter head can be effectively improved, thereby improving the drilling and cutting efficiency.

[0049] The above are only preferred embodiments of the present invention, and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A cutter head for a diamond thin-wall drill bit, comprising a cutter head body, characterized in that: The outer surface of the cutter head body is provided with three straight corrugated grooves at intervals. The raw materials of the cutter head body include a metal powder mixture and diamond particles, wherein the volume fraction of the diamond particles is 30%-50%, and the particle size is 400-600 μm. The metal powder mixture includes the following raw materials in weight percentage: nano cobalt powder 40%-60%, atomized copper tin powder 20%-30%, nano nickel powder 5%-15% and cast carbide powder 5%-15%.

2. A cutter head for a diamond thin-wall drill bit according to claim 1, characterized in that: The inner surface of the cutter head body is provided with two straight corrugated grooves at intervals.

3. A cutter head for a diamond thin-wall drill bit according to claim 2, characterized in that: The top surface of the cutter head body is provided with three V-shaped grooves at intervals.

4. A cutter head for a diamond thin-wall drill bit according to claim 2, characterized in that: The straight groove corrugated groove structure on the inner and outer sides of the cutter head body is the same, the bottom width of the straight groove corrugated groove is 0.5mm-3mm, the top width is 1mm-5mm, and the depth is 0.5mm-1.5mm.

5. A cutter head for a diamond thin-wall drill bit according to claim 4, characterized in that: The straight grooves and corrugated grooves on the outer side and the inner side of the cutter head body are arranged crosswise.

6. A cutter head for a diamond thin-wall drill bit according to claim 3, characterized in that: The depth of the V-shaped groove is 0.5mm-3mm, and the width of the top is 2mm-5mm.

7. A method for preparing a cutter head for a diamond thin-wall drill bit according to any one of claims 1 to 6, characterized in that: The specific preparation steps include: (1) Ingredients: Weigh the following raw materials in the following weight proportions: 40-60 parts of nano cobalt powder, 20-30 parts of atomized copper tin powder, 5-15 parts of nano nickel powder, 5-15 parts of casting carbide powder, and 30%-50% by volume of diamond particles (based on 400%), and mix the above raw materials to obtain alloy matrix powder; (2) Mixing: Put the alloy matrix powder obtained in step (1) into a mixer, add steel balls and dry mix for 1 hour, then add alcohol and mix for 1 hour; (3) Granulation: Add 30 g / kg of granulating agent to the powder mixed in step (2) above, and add 800 ml / kg of isopropanol at the same time, stirring continuously during the addition process, and after stirring evenly, pass through a 20# sieve, and then put it into an oven for baking at a temperature of 100°C for a baking time of 1 hour. Finally, pour the dried powder into a 30# sieve and sieve to disperse the lumps; (4) Cold pressing: cold pressing the powder granulated in step (3) into a cold pressed blank according to the weight required by the cutter head; (5) Hot pressing and sintering: the cutter head after cold pressing in the above step (4) is placed in a graphite mold for hot pressing and sintering, the sintering temperature is 850-920°C, the pressure is 35Mpa, and the holding time is 300S; (6) Subsequent processing: The cutter head sintered in the above step (5) is deburred, and the curvature of the welding surface is ground, sharpened, and polished to finally obtain a cutter head with the required curvature.

8. A diamond thin-wall drill bit, characterized in that: The diamond thin-wall drill bit comprises a cutter head as described in any one of claims 1 to 6 or a cutter head prepared according to claim 7, wherein the diamond thin-wall drill bit further comprises a diamond matrix, and the cutter head is welded to the diamond matrix.

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