Hole boring tool for deep hole machining of steel pipe

Abstract

The utility model provides a boring cutter for processing a deep hole of a steel pipe, which comprises a cutter bar and an indexable blade, one end of the cutter bar is provided with a positioning groove for installing the indexable blade, the front end of the positioning groove is respectively provided with a first notch and a second notch, and the first notch and the second notch are communicated with each other. The first notch is used for allowing an auxiliary cutting edge of the indexable blade to extend out of the positioning groove, and the second notch is used for allowing a main cutting edge of the indexable blade to extend out of the positioning groove; and an included angle of 50-60 degrees is formed between the main cutting edge and the side edge of the cutter bar. The boring cutter for steel pipe deep hole machining can improve machining stability and machining efficiency during steel pipe deep hole boring machining, and can be suitable for boring machining of an inner hole of a hydraulic oil cylinder barrel.

Description

Technical Field

[0001] This utility model relates to the field of machining tools, specifically, to a boring tool for machining deep holes in steel pipes. Background Technology

[0002] With the rapid development of the coal mining machinery and engineering machinery manufacturing industries, hydraulic cylinders, as key components, have seen their cylinder bore machining quality, efficiency, and cost control become a major focus of the industry. The stability and efficiency of deep hole boring tools directly affect the production efficiency and product quality of hydraulic cylinders. Currently, deep hole boring tools need to increase the tool tip angle to improve machining efficiency while ensuring tool stability. Simultaneously, positive rake angle inserts are required to reduce cutting forces; and to reduce the surface roughness after boring, the tool tip radius needs to be increased and the secondary cutting edge angle reduced. Furthermore, the tools must accommodate larger machining allowances and meet machining economic requirements. However, existing deep hole boring tools often suffer from poor balance between machining stability and economy, making it difficult to meet the high requirements of machining the inner bore of hydraulic cylinders.

[0003] Patent application CN118808695A discloses a boring tool and a boring method. The boring tool includes a front guide positioning structure, a cutting component, a tool body, and a tool setting assembly. The tool setting assembly is fitted onto the front guide positioning structure to determine the cutting diameter. The cutting component is housed within the tool body, and the cutting diameter is adjusted by an adjusting locking assembly located within the tool body. In practice, the height of the cutting component is first adjusted according to the tool setting assembly. After removing the tool setting assembly, the first boring operation is performed. A different sized tool setting assembly is then used to adjust the cutting component height again. After removing the tool setting assembly, the second boring operation is performed. Another sized tool setting assembly is used to adjust the cutting component height again. After removing the tool setting assembly, the boring is performed to the final size. This boring tool enables fast and precise tool setting with an adjustable boring tool, solving the problem of increased tool tip rotation diameter due to radial runout and deflection, and enabling precision boring. However, this boring tool is not suitable for machining the inner bore of hydraulic cylinder barrels with large depths of cut. Utility Model Content

[0004] In order to improve machining stability and efficiency, reduce machining costs, and withstand the large impact forces during deep hole boring of steel pipes, this utility model adopts the following technical solution: a boring tool for deep hole machining of steel pipes, including a tool holder and an indexable insert. One end of the tool holder is provided with a positioning groove for mounting the indexable insert. The front end of the positioning groove is provided with a first notch and a second notch. The first notch is used for the secondary cutting edge of the indexable insert to extend out of the positioning groove, and the second notch is used for the main cutting edge of the indexable insert to extend out of the positioning groove.

[0005] The main cutting edge forms an angle of 50 to 60 degrees with the side of the tool holder.

[0006] Based on the above, the indexable insert is provided with a first blade back angle and a second blade back angle at the blade tip, the main cutting edge, and the secondary cutting edge, respectively. The first blade back angle and the second blade back angle are connected. The angle of the first blade back angle is 1 degree to 5 degrees, and the angle of the second blade back angle is 7 degrees to 11 degrees.

[0007] Based on the above, in order to improve the chip breaking effect, ensure that the chips do not wrap around the tool holder and do not affect the accuracy of the bored hole, the indexable insert is also provided with a chip breaking groove formed by molding.

[0008] Based on the above, in order to balance the sharpness of the cutting edge and the impact resistance, and to facilitate the manufacture of indexable inserts, the chip breaker groove is a U-shaped chip breaker groove, wherein the shape and number of the chip breaker groove can be adjusted to match the corresponding material being processed.

[0009] Based on the above, in order to facilitate clamping, the sidewall of the positioning groove is formed with a blade positioning slope with an inclination angle of 7 to 11 degrees.

[0010] Based on the above, in order to avoid interference during the machining of the workpiece, the front end of the tool holder is provided with a first clearance bevel and a second clearance bevel for avoiding the indexable insert.

[0011] Based on the above, in order to facilitate installation and replacement, a threaded hole is provided in the positioning groove, and a blade fixing hole is provided on the indexable blade. A fastening screw is provided in the blade fixing hole, and the indexable blade is detachably engaged with the blade holder through the fastening screw.

[0012] Based on the above, the tool holder is provided with a tool holder fixing hole for connecting the boring bar.

[0013] Based on the above, in order to improve machining efficiency, a plurality of tool holders are evenly spaced on one end of the boring bar, and each tool holder is equipped with an indexable insert. The cutting edge of the indexable insert is treated with a negative chamfer of 0° to 20°.

[0014] Based on the above, the indexable insert is an equilateral hexagonal indexable coated insert with six cutting edges.

[0015] This utility model has substantial features and progress compared with the prior art. Specifically, the boring tool for deep hole machining of steel pipes provided by this utility model adopts a coated indexable insert, which can adjust the insert material and coating according to the machining object. The insert has a long life and the cutting edge can be replaced by simply loosening the clamping screw after the insert wears out. Especially for deep hole boring, the machining efficiency is high, the continuity is good and the quality stability is good.

[0016] Meanwhile, the cutting edge of the indexable insert is designed to be molded and has a U-shaped chip breaker groove, thereby balancing the sharpness of the cutting edge and its impact resistance, reducing the cutting force, making it particularly suitable for deep-cut boring, with good chip breaking effect, preventing chips from wrapping around the tool holder, and not affecting the machining accuracy of the bored hole.

[0017] Furthermore, the boring tool adopts a principal cutting edge angle of 50 to 60 degrees, which can ensure that under the condition of large depth of cut, the contact area between the cutting edge and the workpiece is increased, the cutting force concentration is reduced, the impact resistance of the insert is improved, and the cutting stability is improved.

[0018] Therefore, this boring tool can improve machining stability and efficiency, ensure economy, and is suitable for boring the inner hole of hydraulic cylinder barrel when machining deep holes in steel pipes. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the disassembled structure of the boring tool for deep hole machining of steel pipes provided by this utility model.

[0020] Figure 2 This is a schematic diagram of the overall assembly structure of the boring tool for deep hole machining of steel pipes provided by this utility model.

[0021] Figure 3 This is a schematic diagram of the tool holder structure in the boring tool for deep hole machining of steel pipes provided by this utility model.

[0022] Figure 4 This is a schematic diagram of the overall structure of the indexable insert in the boring tool for deep hole machining of steel pipes provided by this utility model.

[0023] Figure 5 This is a schematic diagram of the side structure of the indexable insert in the boring tool for deep hole machining of steel pipes provided by this utility model.

[0024] Figure 6 This is a schematic diagram of the cross-sectional structure of the indexable insert in the boring tool for deep hole machining of steel pipes provided by this utility model.

[0025] Figure 7 This is a schematic diagram showing the usage state of the boring tool for deep hole machining of steel pipes provided by this utility model.

[0026] In the diagram: 1. Tool holder; 2. Tool holder fixing hole; 3. First notch; 4. Threaded hole; 5. Second notch; 6. Insert positioning bevel; 7. Indexable insert; 8. Insert fixing hole; 9. Fastening screw; 10. Main cutting edge; 11. Secondary cutting edge; 12. First clearance bevel; 13. Second clearance bevel; 14. Negative chamfer; 15. Cutting break groove; 16. First insert clearance angle; 17. Second insert clearance angle; 18. Hydraulic cylinder barrel; 19. Boring bar. Detailed Implementation

[0027] The technical solution of this utility model will be further described in detail below through specific embodiments.

[0028] Example 1

[0029] This embodiment provides a boring tool for deep hole machining of steel pipes, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, the tool includes a tool holder 1 and an indexable insert 7. One end of the tool holder 1 has a positioning groove for mounting the indexable insert 7. The front end of the positioning groove has a first notch 3 and a second notch 5. The first notch 3 allows the secondary cutting edge 11 of the indexable insert 7 to extend out of the positioning groove. The second notch 5 allows the main cutting edge 10 of the indexable insert 7 to extend out of the positioning groove. The main cutting edge 10 forms an angle of 50 to 60 degrees with the side of the tool holder 1.

[0030] In this embodiment, a first blade clearance angle 16 and a second blade clearance angle 17 are respectively provided at the tip of the indexable insert 7, the main cutting edge 10 of the indexable insert 7, and the secondary cutting edge 11 of the indexable insert 7. The first blade clearance angle 16 and the second blade clearance angle 17 are connected, the angle of the first blade clearance angle 16 is 1 degree to 5 degrees, and the angle of the second blade clearance angle 17 is 7 degrees to 11 degrees. The cutting edge of the indexable insert has a negative chamfer 14 of 0° to 20°.

[0031] In this embodiment, the indexable insert is an equilateral hexagonal indexable coated insert with six cutting edges.

[0032] Example 2

[0033] This embodiment provides a boring tool for deep hole machining of steel pipes. The main difference from Embodiment 1 is that, in this embodiment, to improve chip breaking performance and ensure that chips do not entangle the tool holder and affect the boring accuracy, the indexable insert 7 is further provided with a die-formed chip breaker groove 15. Specifically, to balance the sharpness of the cutting edge and impact resistance, and to facilitate the manufacturing of the indexable insert, the chip breaker groove 15 in this embodiment is a U-shaped chip breaker groove. The shape and number of chip breaker grooves can be adjusted to match the material being machined.

[0034] Example 3

[0035] This embodiment provides a boring tool for deep hole machining of steel pipes. The main difference from Embodiment 1 is that, in this embodiment, for ease of clamping, the sidewall of the positioning groove forms a cutting tool positioning slope 6 with an inclination angle of 7 to 11 degrees. For easy installation and replacement of the indexable cutting tool, a threaded hole 4 is provided in the positioning groove, and a cutting tool fixing hole 8 is provided on the indexable cutting tool 7. A fastening screw 9 is provided in the cutting tool fixing hole 8, and the indexable cutting tool 7 is detachably engaged with the tool holder 1 via the fastening screw 9.

[0036] Example 4

[0037] This embodiment provides a boring tool for deep hole machining of steel pipes. The main difference from Embodiment 1 is that, in order to avoid interference during the machining process, the front end of the tool holder 1 is provided with a first clearance bevel 12 and a second clearance bevel 13 for avoiding the indexable insert 7.

[0038] Example 5

[0039] This embodiment provides a boring tool for deep hole machining of steel pipes. The main difference from Embodiment 1 is that, in this embodiment, to improve machining efficiency, the tool holder 1 has a tool holder fixing hole 2 for connecting the boring bar 19. To further improve machining efficiency, a plurality of tool holders 1 are evenly spaced at one end of the boring bar 19, and each tool holder 1 is equipped with an indexable insert 7. During machining, the boring bar 19, carrying the tool holders 1, penetrates into one end of the hydraulic cylinder barrel 18, and the indexable inserts 7 on the tool holders 1 bore the inner wall of the hydraulic cylinder barrel 18.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A boring tool for machining deep holes in steel pipes, comprising a tool holder and an indexable insert, characterized in that: One end of the tool holder is provided with a positioning groove for mounting the indexable insert. The front end of the positioning groove is provided with a first notch and a second notch. The first notch is used for the secondary cutting edge of the indexable insert to extend out of the positioning groove, and the second notch is used for the main cutting edge of the indexable insert to extend out of the positioning groove. The main cutting edge forms an angle of 50 to 60 degrees with the side of the tool holder.

2. The boring tool for deep hole machining of steel pipes according to claim 1, characterized in that: The indexable insert has a first back rake angle and a second back rake angle at its tip, main cutting edge, and secondary cutting edge. The first back rake angle and the second back rake angle are connected. The angle of the first back rake angle is 1 degree to 5 degrees, and the angle of the second back rake angle is 7 degrees to 11 degrees.

3. The boring tool for deep hole machining of steel pipes according to claim 2, characterized in that: The indexable cutting tool is also provided with a chip breaking groove formed by molding.

4. The boring tool for deep hole machining of steel pipes according to claim 3, characterized in that: The chip breaking groove is a U-shaped chip breaking groove.

5. The boring tool for deep hole machining of steel pipes according to claim 4, characterized in that: The sidewall of the positioning groove forms a blade positioning slope with an inclination angle of 7 to 11 degrees.

6. The boring tool for deep hole machining of steel pipes according to claim 1, 2, 3, 4, or 5, characterized in that: The front end of the tool holder is provided with a first clearance bevel and a second clearance bevel for avoiding the indexable cutting tool.

7. The boring tool for deep hole machining of steel pipes according to claim 1, characterized in that: The positioning groove has a threaded hole, and the indexable blade has a blade fixing hole. A fastening screw is installed in the blade fixing hole, and the indexable blade is detachably engaged with the blade holder through the fastening screw.

8. The boring tool for deep hole machining of steel pipes according to claim 1 or 7, characterized in that: The tool holder has a tool holder fixing hole for connecting the boring bar.

9. The boring tool for deep hole machining of steel pipes according to claim 8, characterized in that: The boring bar has a plurality of tool holders evenly spaced at one end, and each tool holder is equipped with an indexable cutting tool.

10. The boring tool for deep hole machining of steel pipes according to claim 9, characterized in that: The indexable insert is an equilateral hexagonal indexable coated insert.

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