Superhard single-tooth bta deep hole drill tool and machining method

Abstract

The application discloses a kind of superhard single-tooth BTA deep hole drill cutters and processing methods, including blade and tool body, blade is cubic boron nitride blade, the first end of tool body is used to install blade, the second end of tool body is used to connect with drill rod;The cutting edge of blade includes outer blade, center blade and intermediate blade sequentially distributed and arranged in axial step, and each cutting edge is arranged at a preset angle, and each cutting edge is staggered in axial different depth for chip division respectively.The blade is made of PCBN superhard material, increases the rigidity of blade, reduces the transverse vibration of blade during work, improves the stability of tool system, reduces the distortion of drill rod, reasonably designs the angle of each cutting edge, uses each cutting edge to stagger in axial different depth position for chip division, and then forms narrow chip, to ensure the stability of drilling.

Description

Technical Field

[0001] This invention relates to the field of deep hole drilling, and in particular, to a superhard single-tooth BTA deep hole drilling tool and its machining method. Background Technology

[0002] Nickel-based superalloys and other difficult-to-machine materials have excellent comprehensive properties such as high strength, fatigue resistance, oxidation resistance, radiation resistance, and corrosion resistance. Their applications in industries such as automobiles and aerospace are becoming increasingly widespread, but they also place higher precision requirements on machining technology.

[0003] The rapid wear and cutting performance of cutting tools directly restrict the performance and application of parts. Although BTA deep hole drilling technology is widely used, it still has some shortcomings, such as:

[0004] 1) BTA deep hole drills with a diameter less than φ25mm have narrow chip removal channels, and nickel-based high-temperature alloys have high strength, making chip separation and breaking difficult. During the machining process, chip blockage can easily occur, leading to machine downtime.

[0005] 2) Nickel-based high-temperature alloys are difficult to machine. During drilling, the wear rate of carbide cutting tools is fast and the wear amount is large, resulting in large cutting forces, which seriously affects the improvement of machining quality and machining efficiency.

[0006] 3) An unreasonable design of the guide block's circumferential distribution angle and hysteresis will exacerbate the problem of borehole axis deviation and make it difficult to ensure drilling stability;

[0007] 4) In special application scenarios such as cutting fluid pressure greater than 4 MPa, BTA deep hole drilling threads are prone to plastic deformation and creep under periodic high stress loads and high pressure coupling, which can lead to stripping failure.

[0008] 5) The connection strength and rigidity between the mechanically clamped single-tooth BTA drill bit and the tool body are insufficient. During deep hole machining, the bit is prone to vibration when it encounters hard particles in nickel-based high-temperature alloys, resulting in poor machining accuracy. Summary of the Invention

[0009] This invention provides an ultrahard single-tooth BTA deep hole drilling tool and machining method to solve the technical problems of existing tools being prone to chip clogging, high wear of carbide inserts, high cutting force, and low machining efficiency.

[0010] The technical solution adopted in this invention is as follows:

[0011] A superhard single-tooth BTA deep hole drill bit is used for deep hole machining of nickel-based superalloys with a small diameter of φ15mm-25mm and a large length-to-diameter ratio. It includes an insert and a tool body. The insert is a cubic boron carbide insert. The first end of the tool body is used to mount the insert, and the second end of the tool body is used to connect to the drill rod. The cutting edge of the insert includes an outer cutting edge, a center cutting edge, and an intermediate cutting edge arranged in a stepped manner along the axial direction. A chip-breaking platform is formed between each cutting edge, and the cutting edges are arranged at a preset angle. Each cutting edge is used to machine at different depths in the axial direction to perform chip breaking.

[0012] As a further improvement to the above technical solution, the angle between the central cutting edge and the main cutting plane is the first co-cutting angle, which is 8° to 15°; the angle between the intermediate cutting edge and the main cutting plane is the second co-cutting angle, which is 10° to 15°; the angle between the outer cutting edge and the main cutting plane is the second co-cutting angle, which is 10° to 15°; and the angle between the co-cutting angles of each cutting edge is less than 4°.

[0013] As a further improvement to the above technical solution, the mating surfaces of the blade and the blade body are respectively provided with matching wavy oblique textured grooves set at a preset angle, and the two sets of oblique textured grooves have matching tooth profiles.

[0014] As a further improvement to the above technical solution, the oblique weave grooves are arranged on the blade body at an angle of 9° to 10°, with a groove width of 0.12 to 0.2 mm at the bottom, a tooth spacing of 0.2 to 0.4 mm, a tooth crest width of 0.15 to 0.2 mm, and a weave height of 70° to 90°.

[0015] As a further improvement to the above technical solution, the cutting edge of the blade is provided with a chip breaking platform, which is used to accelerate the plastic deformation of the chips flowing over the cutting edge to form small-sized C-shaped chips.

[0016] As a further improvement to the above technical solution, the circumferential surface of the blade body is provided with a first guide block and a second guide block along the axial direction; the included angle between the blade and the first guide block is 82° to 87°, the included angle between the blade and the second guide block is 180° to 186°, and the hysteresis of the first guide block relative to the outer edge of the blade's outer cutting edge in the axial direction is 0.1 to 0.5 mm.

[0017] As a further improvement to the above technical solution, the blade body is made of 9CrWMn cold work die steel, and the threaded part of the blade body is strengthened by laser impact.

[0018] As a further improvement to the above technical solution, the blade body is provided with a mounting groove for installing a shock-absorbing strip. The mounting groove is located 2-5mm directly below the assembled blade, and the shock-absorbing strip is a nylon resin fiber strip.

[0019] As a further improvement to the above technical solution, a radial damping support block is installed on the blade body, and the radial damping support block is an alumina ceramic block.

[0020] According to another aspect of the present invention, a method for machining a superhard single-tooth BTA deep hole drill bit is also provided, for machining any of the superhard single-tooth BTA deep hole drill bits described above, the machining method comprising:

[0021] Wire electrical discharge machining is used to cut PCBN sheets to create cutting edges, chip breaking stages, and texture grooves.

[0022] The cutting edge profile of the insert is precision ground using a five-axis linkage method;

[0023] The texture tank is ultrasonically cleaned by sequentially using a water-based cleaning solution containing chromic anhydride and pure water to ultrasonically clean the blade.

[0024] Drying process.

[0025] This invention offers the following advantages: The cutting inserts are made of PCBN superhard material, increasing tool rigidity and reducing lateral vibration during operation, thus improving tool system stability and minimizing drill rod torsional deformation. PCBN material tools exhibit low thermal deformation, high elastic modulus, and high fracture strength. Therefore, indexable BTA deep hole drills with PCBN inserts can achieve sharp cutting edges, resulting in higher machining quality. The surface quality of the drilled holes is also significantly better than traditional carbide BTA drills, enabling better control of straightness deviation in high-aspect-ratio deep holes made of difficult-to-machine high-temperature nickel-based alloys. The cutting edges of the inserts are arranged in a stepped pattern along the axial direction to form chip-breaking platforms. Each chip-breaking platform contains an outer cutting edge, a center cutting edge, and an intermediate cutting edge. The angles of each cutting edge are rationally designed to reduce machining stress. By utilizing the staggered machining positions of the cutting edges at different depths along the axial direction, chip breaking is achieved, resulting in narrow chips and ensuring drilling stability.

[0026] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the cutting tool structure according to a preferred embodiment of the present invention;

[0029] Figure 2This is a front view of the cutting tool according to a preferred embodiment of the present invention;

[0030] Figure 3 This is a side view of the cutting tool according to a preferred embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram of the blade body structure according to a preferred embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of the blade mating surface structure according to a preferred embodiment of the present invention;

[0033] Figure 6 This is a front view of the blade according to a preferred embodiment of the present invention;

[0034] Figure 7 This is a radial support block according to a preferred embodiment of the present invention;

[0035] Figure 8 This is a schematic diagram of the shock-absorbing strip structure according to a preferred embodiment of the present invention;

[0036] Figure 9 This is a schematic diagram of the guide block structure according to a preferred embodiment of the present invention.

[0037] In the diagram: 1. Second guide block; 2. Tool body 2a, chip removal port 2b, first texture groove 2c, positioning support groove 2d, multi-line rectangular thread 2e, mounting groove 2g, first embedding groove 2f, second embedding groove 3, screw; 4. Blade 4a, second texture groove 4b, center cutting edge 4c, intermediate cutting edge 4d, chip breaking table 4e, outer cutting edge 4f, threaded hole 4g, drill tip eccentricity 4h, first redundant deflection angle 4i, second redundant deflection angle 4j, third redundant deflection angle 4k, chip breaking table; 5. First guide block; 6. Radial support block; 7. Vibration damping strip. Detailed Implementation

[0038] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] Reference Figures 1 to 9 A preferred embodiment of the present invention provides a superhard single-tooth BTA deep hole drill bit for machining deep holes of nickel-based superalloys with a small diameter of φ15mm-25mm and a large length-to-diameter ratio. It includes a superhard alloy insert 4 and a tool body 2 for mounting the insert 4. The insert 4 is a cubic boron carbide insert 4. The tail end of the tool body 2 is provided with a thread for connecting with the drill rod. The insert 4 has a drill tip eccentricity 4g. The cutting edge of the insert 4 includes an outer cutting edge 4e, a center cutting edge 4b ​​and an intermediate cutting edge 4c arranged in a stepped manner along the axial direction. A chip-breaking platform is formed between each cutting edge. Each cutting edge is arranged at a preset angle and is used to machine at different depths in the axial direction to perform chip breaking.

[0040] Among them, the cutting tool 4 is a cubic boron carbide (PCBN) cutting tool 4, which has the characteristics of high hardness, high strength, high wear resistance, good thermal conductivity and good thermal stability. It has good cutting performance in cutting difficult-to-machine materials such as high-temperature alloys, especially in deep hole drilling of nickel-based high-temperature alloys, which can effectively reduce tool wear and extend tool life. At the same time, it has significant advantages in solving the problem of axis misalignment in the machining of large length-to-diameter ratio and small diameter deep holes. The head end of the tool body 2 is used to install the cutting tool 4, and the tail end is threaded for connection with the drill rod. The tool body 2 has a chip discharge port 2a for guiding the chips out.

[0041] Understandably, this insert is made of PCBN superhard material, which increases the insert's rigidity, reduces lateral vibration during operation, improves the stability of the tool system, and reduces drill rod torsional deformation. PCBN material inserts have low thermal deformation, high elastic modulus, and high fracture strength. Therefore, the indexable BTA deep hole drill with PCBN insert 4 can be ground to a sharp edge, resulting in higher machining quality. The surface quality of the drilled hole is also very high, better than that of traditional carbide BTA drills, and it can better control the straightness deviation of deep holes with large aspect ratios in difficult-to-machine high-temperature nickel-based alloy materials. The cutting edges of insert 4 are distributed in a stepped manner along the axial direction to form chip-breaking stages 4d. Each chip-breaking stage 4d has an outer cutting edge 4e, a center cutting edge 4b, and an intermediate cutting edge 4c. The angle of each cutting edge is reasonably designed to reduce the machining stress acting on the cutting edge. By using the staggered machining of each cutting edge at different depths along the axial direction, chip breaking is achieved, thereby forming narrow chips and ensuring drilling stability.

[0042] Furthermore, the cutting face of the blade 4 is provided with a chip breaking platform 4k, which works in conjunction with the chip separating platform 4d to accelerate the plastic deformation of the chips flowing over the cutting face to form smaller C-shaped chips, so that the chips are separated and discharged from the beginning and pass through the chip discharge channel more smoothly.

[0043] In this embodiment, the height of the chip-breaking stage 4d is 0.5–0.7 mm; the angle between the center cutting edge 4b ​​and the main cutting plane is the first co-cutting angle 4h, which is 8°–15°; the angle between the intermediate cutting edge 4c and the main cutting plane is the second co-cutting angle 4i, which is 10°–15°; the angle between the outer cutting edge 4e and the main cutting plane is the second co-cutting angle 4i; the third co-cutting angle 4j is 10°–15°; the difference in co-cutting angles between each cutting edge is less than 4°; and the side clearance angle of each chip-breaking stage is 20°–25°. In deep hole machining, the drill rod is long and flexible. Nickel-based high-temperature alloys are typical difficult-to-machine materials, exhibiting significant vibration, severe tool wear, and difficulty in chip removal during drilling, making machining challenging. The chip-breaking stages formed between the cutting edges, with their preset angle distribution, have a synergistic effect of improving chip-breaking capability, reducing tool vibration, and enhancing drilling stability. If the parameters are not within the specified range, an excessively large offset angle will cause significant differences in force on each cutting edge, leading to tool vibration; an excessively small offset angle will increase cutting resistance and accelerate tool wear. A larger chip breaker side clearance angle is also set, making the cutting edge sharper and the drilling process smoother. The chip breaker height setting effectively improves chip breaking; an excessively large chip breaker height can increase radial force on the tool due to increased chip breaker force, resulting in poor hole straightness; an excessively small height makes it difficult to break high-temperature alloy materials and hinders chip breaking. Based on the above angle distribution, this tool is more suitable for deep hole drilling of nickel-based high-temperature alloy materials, and it more effectively controls chip formation and drilling stability compared to existing conventional tools.

[0044] In this embodiment, the mating surfaces of the blade 4 and the cutter body 2 are respectively provided with matching wavy oblique textured grooves set at a preset angle. The mating surface of the cutter body 2 has a first textured groove 2b, and the mating surface of the blade 4 has a second textured groove 4a. The two sets of oblique textured grooves have matching tooth shapes, with 'peaks' and 'troughs'. The uneven textured structure of the mating surfaces of the two blades 'interlocks', and the 'peaks' and 'troughs' of the textured grooves on the two mating surfaces are interlocked with each other. The oblique textured grooves are set at a preset angle, thereby effectively preventing the blade 4 from axially and radially 'moving' relative to the cutter body 2 during drilling, reducing the cutting vibration of the tool, and further improving the drilling stability of the cutter body 2 in a high-pressure coolant environment.

[0045] Specifically, the oblique texture grooves are arranged at an angle of 9° to 10° relative to the rake face of the cutting tool. The tooth radius of the oblique texture grooves is 0.12 to 0.2 mm, the tooth pitch is 0.2 to 0.4 mm, the tooth crest width is 0.15 to 0.2 mm, and the texture angle is 70° to 90°. If the texture groove angle distribution is too large, the support force on the cutting tool body will be too small, and if the angle value distribution is too small, the drilling force will affect the texture strength. The tooth pitch, tooth crest width, tooth root groove width, and texture height settings can all ensure texture strength and reasonable matching of the force on the cutting tool and the cutting tool body. The oblique texture is set on the mating surface of the cutting tool back and the cutting tool body, which increases the effective contact area between the cutting tool and the cutting tool body, and can effectively prevent the cutting tool 4 from moving axially and radially relative to the cutting tool body 2 during drilling, and reduce cutting vibration.

[0046] In this embodiment, the circumferential surface of the cutter body 2 is provided with a first guide block 5 and a second guide block 1 along the axial direction. The cutter body 2 is provided with a first embedding groove 2g for mounting the first guide block 5 and a second embedding groove 2f for mounting the second guide block 1. The included angle α between the blade 4 and the first guide block 5 is 82°–87°, and the included angle α0 between the first guide bar 5 and the second guide bar 1 is 93°–106°, i.e., the clockwise included angle between the blade 4 and the second guide block 1 is 180°–186°. The hysteresis of the first guide block 5 relative to the outer edge of the outer cutting edge 4e of the blade 4 in the axial direction is 0.1–0.5 mm. Because the cutting force is large when machining high-temperature alloy materials, this embodiment changes the distribution angle of the existing blade 4 and guide block, so that most of the forces acting on the blade 4 and guide block during the deep hole drilling process of nickel-based high-temperature alloys can cancel each other out. Furthermore, it allows the guide block to always feed close to the inner hole wall, thereby reducing the axial deviation of the BTA drill and ensuring straightness. This angular distribution setting allows for more effective balancing of drilling forces, improving tool dynamic balance and drilling stability. Simultaneously, the hysteresis of the guide block and outer cutting edge is adjusted to more effectively ensure the dimensional accuracy of the hole formed at the tool entry point. It should be noted that excessive hysteresis prevents the tool from forming a "three-point circle" at the drilling end, leading to tool vibration at the start of drilling and affecting hole dimensional accuracy. Insufficient hysteresis can introduce errors during tool body machining, potentially causing negative hysteresis between the guide bar and outer cutting edge, resulting in the guide bar height exceeding the cutting edge height, thus preventing drilling.

[0047] It should be noted that in this embodiment, the blade 4 and the blade body 2 are connected by screws 3, as are the guide block and the blade body 2. This allows for timely and quick replacement of worn blades 4 or guide blocks, effectively improving processing efficiency and reducing production costs.

[0048] In this embodiment, the cutter body 2 is made of 9CrWMn cold work die steel, and the thread of the cutter body 2 is laser-strengthened with multi-line rectangular square thread. At the same time, the thread connection is laser-strengthened to improve the subsurface hardness of the thread. Under high pressure, the thread is not prone to deformation and slippage failure. The connection between the drill rod and the drill bit is highly reliable, which improves the stability of deep hole drilling.

[0049] In this embodiment, the cutter body 2 is provided with a mounting groove 2e for mounting the damping strip 7. The mounting groove 2e is located 2-5 mm directly below the assembled cutter 4. The damping strip 7 is a nylon resin fiber strip with strong flexibility. Compared with the existing single-tooth BTA drill using the "three-point circle fixing" method, this structure indirectly increases the contact area between the cutter 4 and the hole wall by setting the damping strip 7 directly below the cutter 4, thereby achieving "multi-point circle fixing". This has a better stability effect and effectively avoids the impact of hard points in the nickel-based alloy on the cutter 4 during drilling, thus preventing instability in the drilling process and avoiding affecting the machining accuracy.

[0050] In this embodiment, a radial damping support block is installed on the tool body 2 to support one side of the cutting tool 4. This radial damping support block is an alumina ceramic block, which has higher hardness and strength than the tool body 2 material. This prevents the cutting tool 4 from directly impacting the tool body 2, reduces the impact of cutting load on the tool body 2, and prevents plastic deformation and crack damage to the tool body 2. This effectively prevents the deep hole drilling tool body 2 from deforming due to insufficient rigidity, which could lead to misalignment or tilting of the cutting tool 4 and the positioning surface, resulting in decreased deep hole machining accuracy, thus improving the stability of the deep hole drilling system.

[0051] The alumina ceramic radial support block 6 and the cutter body 2 are connected by screws 3, which facilitates disassembly and timely replacement of damaged parts; the cutter body 2 has a positioning support groove 2c for installing the radial support block 6.

[0052] On the other hand, this embodiment also provides a method for machining the above-mentioned superhard single-tooth BTA deep hole drill bit, including:

[0053] S1. PCBN sheets are cut using wire electrical discharge machining to produce cutting edges, chip breaking stages 4k, and texture grooves;

[0054] The machining substrate of insert 4 is made of a single PCBN sheet. Compared with carbide insert 4, insert 4 has higher hardness, lower coefficient of friction, better wear resistance and thermal conductivity, which can effectively improve the wear resistance of insert 4 and greatly increase the service life of deep hole drilling tools. At the same time, it can achieve high-speed cutting, significantly reduce cutting force and torque, and effectively improve workpiece machining efficiency.

[0055] Specifically, the PCBN insert 4 has a length of 8–20 mm and a width of 6–13 mm, allowing for flexible design of the cutting point. After the cutting edge, chip breaker 4k, and back texture groove of the PCBN insert 4 are cut by wire electrical discharge machining (EDM), a machining allowance of 0.5–1 mm is left, resulting in structures such as the PCBN back angle, side back angle, offset angle, and positioning chamfer chip removal groove. The EDM uses slow wire cutting with a wire speed of 0.2 mm / s, which can improve the manufacturing accuracy of the insert and reduce insert damage to a greater extent compared with fast and medium-speed wire cutting.

[0056] S2. The cutting edge of the insert 4 is precision ground using a five-axis linkage method to meet the final machining cutting edge accuracy.

[0057] S3. Perform ultrasonic cleaning on the texture tank by sequentially using a water-based cleaning solution containing chromic anhydride and pure water to ultrasonically clean the blade 4.

[0058] Specifically, the texture grooves of the PCBN blade 4 are ultrasonically cleaned at a frequency of 28–40 kHz after electrical discharge machining. The PCBN blade 4 is ultrasonically cleaned sequentially using a water-based cleaning solution containing chromic anhydride and then pure water.

[0059] S4. Drying treatment.

[0060] In this embodiment, the blade 4 and the tool body 2 are connected by screws 3. Based on this, a method for machining the screw holes in the blade 4 is also provided: the blade 4 is drilled using an electrical discharge machining (EDM) machine, with careful adjustment of the pulse interval, pulse width, machining current, and machining allowance. Specifically, the pulse current is 6–10 A, the pulse width is 60–120 μs, the pulse interval is 80–160 μs, and the working fluid pressure is 6–8 MPa. The shape and positional accuracy of the PCBN threaded hole 4f obtained through this special machining method are consistent with the cross-section of the threaded hole 4f in the tool body 2, thereby ensuring installation accuracy.

[0061] In this embodiment, the method for machining the external thread at the connecting end of the cutter body 2 includes:

[0062] Adjusting the laser power induces a surface hardening layer depth of 0.1 mm on the 2d multi-line rectangular thread structure, achieving a compressive stress of 400 MPa, thereby enhancing the service capability of the threaded portion of the tool body under high-pressure environments. The laser shock process parameters include a power density of 2–4 GW / cm², a pulse width of 10–25 ns, a pulse wavelength of 1–2 μm, a spot diameter of 8–12 mm, a beam energy of 60–80 J, and 2–3 impacts on the same surface to obtain the desired thread.

[0063] In this embodiment, the substrate material of each guide block is preferably domestic YT14 alloy or YG8 cemented carbide. An Al CrN coating is applied to the surface of the guide block within 5um to 10um using physical vapor deposition to improve the wear resistance and strength of the guide block and enhance the polishing effect of the guide block on the hole wall.

[0064] The damping strip 7 is made of nylon polyester fiber and is installed 2-5mm directly below the blade 4 along the axis. The highest point of the outer arc of the damping strip 7 is in the same axial direction as the outer edge of the cutting edge. The damping strip 7 can be obtained by cutting using a commonly used 3-axis or higher machine tool.

[0065] The alumina ceramic radial support block 6 is obtained through a combination of laser cutting and diamond wheel grinding. Water cooling is used during the cutting process to prevent ceramic overheating and deformation. The radial support block 6 has higher hardness and strength than the tool body 2, avoiding direct impact from the insert 4 on the tool body 2, reducing the impact of cutting load on the tool body 2, and preventing plastic deformation and crack damage. This effectively prevents deformation of the deep hole drilling tool body 2 due to insufficient rigidity, which could lead to misalignment or tilting of the insert 4 and the positioning surface, resulting in decreased deep hole machining accuracy. This improves the stability of the deep hole drilling system.

[0066] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A superhard single-tooth BTA deep hole drill bit, used for machining deep holes with a small diameter of φ15mm-25mm and a large length-to-diameter ratio in nickel-based superalloys, characterized in that, The tool includes a cutting blade (4) and a tool body (2). The cutting blade (4) is a cubic boron carbide cutting blade (4). The first end of the tool body (2) is used to install the cutting blade (4), and the second end of the tool body (2) is used to connect to the drill rod. The cutting edge of the cutting blade (4) includes an outer cutting edge (4e), a central cutting edge (4b), and an intermediate cutting edge (4c) arranged in a stepped manner along the axial direction. A chip-breaking platform (4d) is formed between each cutting edge, and each cutting edge is arranged at a preset angle. Each cutting edge is used to process chips at different depths along the axial direction. The tool body (2) is provided with a mounting groove (2e) for installing a shock-absorbing strip (7). The mounting groove (2e) is located 2-5 mm directly below the assembled cutting blade (4). The shock-absorbing strip (7) is a nylon resin fiber strip. A radial shock-absorbing support block is installed on the tool body to support one side of the cutting blade (4). The radial shock-absorbing support block is an alumina ceramic block with a hardness and strength higher than that of the tool body (2) material, in order to avoid the... The blade (4) directly impacts the cutter body (2), reducing the impact of the cutting load on the cutter body (2); the angle between the center cutting edge (4b) and the main cutting plane is the first co-cutting angle (4h), which is 8° to 15°; the angle between the intermediate cutting edge (4c) and the main cutting plane is the second co-cutting angle (4i), which is 10° to 15°; the angle between the outer cutting edge (4e) and the main cutting plane is the second co-cutting angle (4i), which is 10° to 15°; the angle between the outer cutting edge (4e) and the main cutting plane is the third co-cutting angle (4i). The deflection angle (4j) is 10° to 15°, and the difference in the angle of the residual deflection angle of each cutting edge is less than 4°; the mating surfaces of the blade (4) and the blade body (2) are respectively provided with matching wavy oblique texture grooves set at a preset angle, and the two sets of oblique texture grooves have matching tooth profiles; the oblique texture grooves are respectively arranged on the blade body at an angle of 9° to 10°, with a tooth root groove width of 0.12 to 0.2 mm, a tooth pitch of 0.2 to 0.4 mm, and a tooth crest width of 0.15 to 0.2 mm.

2. The superhard single-tooth BTA deep hole drill bit according to claim 1, characterized in that, The cutting edge (4) has a chip breaking platform (4k) on its front cutting face, which is used to accelerate the plastic deformation of the chips flowing over the front cutting face to form small-sized C-shaped chips.

3. The superhard single-tooth BTA deep hole drill bit according to claim 1, characterized in that, The circumferential surface of the blade body (2) is provided with a first guide block (5) and a second guide block (1) along the axial direction; the included angle between the blade (4) and the first guide block (5) is 82° to 87°, the included angle between the blade (4) and the second guide block (1) is 180° to 186°, and the hysteresis of the first guide block (5) relative to the outer edge of the outer cutting edge (4e) of the blade (4) in the axial direction is 0.1 to 0.5 mm.

4. The superhard single-tooth BTA deep hole drill bit according to claim 1, characterized in that, The blade body (2) is made of 9CrWMn cold work die steel, and the threaded part of the blade body (2) is strengthened by laser impact.

5. A method for machining a superhard single-tooth BTA deep hole drill bit, characterized in that, The machining method for processing the superhard single-tooth BTA deep hole drill tool according to any one of claims 1-4 includes: Wire electrical discharge machining is used to cut PCBN sheets to create cutting edges, chip breaking stages, and texture grooves. The cutting edge profile of the insert is precision ground using a five-axis linkage method; The texture tank is ultrasonically cleaned by sequentially using a water-based cleaning solution containing chromic anhydride and pure water to ultrasonically clean the blade. Drying process.

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