Boring tool for inner spherical surface of flange hole

Abstract

The utility model discloses a boring tool for an inner spherical surface of a flange hole, and belongs to the field of machining. A boring tool for the inner spherical surface of a flange hole comprises a boring tool rod and a molded surface boring tool. The boring cutter rod comprises a conical boring cutter rod handle and a rotary cutter rod connected with the boring cutter rod handle, a screw hole matched with the blind rivet is formed in the end of the boring cutter rod handle, a square hole used for installing the molded surface boring cutter is formed in the rotary cutter rod, a bolt used for fastening the molded surface boring cutter is arranged on one side of the square hole, and a threaded hole matched with the threaded hole is formed in the other side of the square hole. The profile boring cutter is specially designed in structure according to the inner spherical surface of a flange hole. Complex machining of the inner spherical surface of the flange hole can be completed at a time, multi-procedure errors are avoided, the size and shape precision is guaranteed, the requirement of a drawing is met, traditional step-by-step machining can be replaced, the tool changing frequency and the clamping time are reduced, efficiency is greatly improved, and production cost is reduced.

Description

Technical Field

[0001] This utility model patent relates to the field of machining in the power energy industry, specifically to a spherical boring process for flange holes. Background Technology

[0002] Traditional flange countersunk holes typically have flat end faces, which can lead to stress concentration during unit operation and cannot compensate for installation errors and thermal expansion. Later, designers changed the flat surface to an inner spherical surface because it has an automatic centering function, reducing installation difficulty. The design of the inner spherical flange hole significantly improves the reliability and durability of the connection by optimizing mechanical properties and assembly adaptability, making it suitable for applications such as steam turbine rotors where high lifespan and dynamic stability are required.

[0003] Machining the spherical surface inside a flange bore requires high technical skill. For medium to large flange bores, ball end boring tools are typically used, with the tool's three-dimensional trajectory controlled by a CNC program to mill the surface. However, the radius of the ball end boring tool must be precisely matched to the radius of the spherical surface inside the flange bore, making it suitable only for flange bores with a single radius. For flange bores with multiple radii, ball end boring tools of different sizes are required. When multiple tools are joined, the tool marks are quite noticeable, affecting the accuracy of the spherical surface inside the flange bore. Furthermore, since the spherical surface inside a flange bore is a closed or semi-closed space, using a ball end boring tool can easily cause chips to accumulate in the machining area, scratching the machined surface and affecting accuracy.

[0004] Therefore, there is an urgent need for a simple and quick tool for machining the spherical surface inside flange holes, which can improve machining efficiency while ensuring machining accuracy. Utility Model Content

[0005] To solve the above-mentioned technical problems, this utility model provides a tool for boring the inner spherical surface of a flange hole. This tool can conveniently and quickly machine the inner spherical surface of the flange hole in one operation, ensuring the contour of the inner spherical surface to guarantee machining accuracy, and eliminating the need for tool changing, thereby improving machining efficiency.

[0006] A tool for boring spherical surfaces inside flange holes includes a boring bar and a profile boring tool; the boring bar includes a conical boring bar shank and a rotary tool bar connected to the boring bar shank shank, the end of the boring bar shank shank is provided with a screw hole that mates with a pull stud, and the rotary tool bar is provided with a square hole for mounting the profile boring tool, and one side of the square hole is provided with a bolt for fastening the profile boring tool;

[0007] The aforementioned profile boring tool includes a square tool holder and a tool head located at the end of the tool holder. The tool head includes a back, a face, a main cutting edge, a secondary cutting edge, a straight cutting edge, a front side, and a rear side. The face is parallel to the top of the tool holder, and the back is located below the face. The main cutting edge is arc-shaped and fits against the spherical surface inside the flange hole. The main cutting edge is located in the middle left side of the face. One end of the main cutting edge is provided with a secondary cutting edge, which is perpendicular to the rear side. The other end of the main cutting edge is provided with a straight cutting edge, which forms a 120° angle with the front side. Chip removal grooves are provided between the main cutting edge, the secondary cutting edge, the straight cutting edge, and the face.

[0008] A further technical solution is that the main cutting edge is composed of two arc segments, including a first arc segment and a second arc segment connected to the first arc segment. The first arc segment is connected to the secondary cutting edge, and the second arc segment is connected to the straight cutting edge. The diameter of the second arc segment is larger than the diameter of the first arc segment.

[0009] In a further technical solution, the back of the blade is inclined inward, and the main cutting edge, the secondary cutting edge, the straight cutting edge and the back of the blade form an 8° angle.

[0010] In a further technical solution, the profile boring tool is made of high-speed steel M42.

[0011] In a further technical solution, the taper of the boring bar shank is 7:24.

[0012] A further technical solution is that the two sides of the boring bar shank are provided with keyways that cooperate with the key on the boring and milling machine spindle. Beneficial effects

[0013] Compared with the prior art, the present invention has the following significant advantages:

[0014] 1. This utility model can complete the complex machining of the spherical surface inside the flange hole in one go, avoiding errors from multiple processes, ensuring dimensional and shape accuracy, and meeting the drawing requirements. It can replace the traditional step-by-step machining, reduce the number of tool changes and clamping time, greatly improve efficiency, and reduce production costs.

[0015] 2. The main cutting edge of this profile boring tool conforms to the dimensional requirements of the inner spherical surface. A secondary cutting edge extends from one end of the main cutting edge, primarily for machining the portion tangent to the arc segment of the inner spherical surface where the countersunk hole meets the profile. The other end is a straight cutting edge connected to the profile, ensuring a smooth connection between the machined inner spherical surface and the through hole, thus guaranteeing the geometric accuracy and surface quality of the spherical surface. Because complex profiles are prone to entangled chips, a chip removal groove is added to prevent chip accumulation and subsequent workpiece scratches, reducing cutting resistance and further ensuring machining accuracy. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the spherical surface inside the flange hole;

[0017] Figure 2 for Figure 1 Enlarged view of L in the image;

[0018] Figure 3 for Figure 2 AA magnified image in the image;

[0019] Figure 4 This is the front view of the boring bar;

[0020] Figure 5 This is the left view of the boring bar;

[0021] Figure 6 This is the front view of the profile boring tool;

[0022] Figure 7 This is the left view of a profile boring tool;

[0023] Figure 8 This is a top view of a profile boring tool;

[0024] The diagram is labeled as follows: 1. Boring tool holder; 2. Profile boring tool; 3. Inner spherical surface of flange hole; 1-1. Boring tool holder shank; 1-2. Rotary tool holder; 1-3. Pull stud; 1-4. Screw hole; 1-5. Square hole; 1-6. Bolt; 2-1. Tool holder; 2-2. Tool head; 2-3. Tool back; 2-4. Tool face; 2-5. Main cutting edge; 2-6. Secondary cutting edge; 2-7. Straight cutting edge; 2-8. Front side; 2-9. Rear side; 2-10. Chip groove; 2-5-1. First arc segment; 2-5-2. Second arc segment. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Example

[0026] like Figure 4-8 As shown, a tool for boring spherical surfaces inside flange holes includes a boring bar 1 and a profile boring tool 2. The boring bar 1 includes a conical boring bar shank 1-1 and a rotary tool bar 1-2 connected to the boring bar shank 1-1. The end of the boring bar shank 1-1 is provided with a screw hole 1-4 that mates with a pull stud 1-3. The rotary tool bar 1-2 is provided with a square hole 1-5 for mounting the profile boring tool 2, and a bolt 1-6 for fastening the profile boring tool 2 is provided on one side of the square hole 1-5.

[0027] The profile boring tool 2 includes a square tool holder 2-1 and a tool head 2-2 located at the end of the tool holder 2-1. The tool head 2-2 includes a back 2-3, a face 2-4, a main cutting edge 2-5, a secondary cutting edge 2-6, a straight cutting edge 2-7, a front side 2-8, and a rear side 2-9. The face 2-4 is parallel to the top of the tool holder 2-1, and the back 2-3 is located below the face 2-4. The main cutting edge 2-5 is arc-shaped and meets the ball inside the flange hole. The main cutting edge 2-5 is located in the middle left side of the tool face 2-4. One end of the main cutting edge 2-5 is provided with a secondary cutting edge 2-6, which is perpendicular to the rear side 2-9. The other end of the main cutting edge 2-5 is provided with a straight cutting edge 2-7, which forms a 120° angle with the front side 2-8. Chip removal grooves 2-10 are provided between the main cutting edge 2-5, the secondary cutting edge 2-6, the straight cutting edge 2-7 and the tool face 2-4.

[0028] The main cutting edge 2-5 consists of two arc segments, including a first arc segment 2-5-1 and a second arc segment 2-5-2 connected to the first arc segment 2-5-1. The first arc segment 2-5-1 is connected to the secondary cutting edge 2-6, and the second arc segment 2-5-2 is connected to the straight cutting edge 2-7. The diameter of the second arc segment 2-5-2 is larger than the diameter of the first arc segment 2-5-1. The structural design of the different arc segments of the main cutting edge allows it to fit snugly against the spherical surface inside the flange hole during machining, ensuring machining accuracy. The diameter of the arc segments is consistent with the diameter of the arc segments within the spherical surface inside the flange hole.

[0029] The back of the blade 2-3 is inclined inward, and the main cutting edge 2-5, the secondary cutting edge 2-6, the straight cutting edge 2-7 form an 8° angle with the back of the blade 2-3.

[0030] The profile boring tool 2 is made of high-speed steel M42.

[0031] The taper of the boring bar shank 1-1 is 7:24.

[0032] The boring bar shank 1-1 has keyways 1-7 on both sides that mate with the key on the boring and milling machine spindle. During installation, the key is locked in the keyway to fix the boring bar.

[0033] The working process of this utility model is as follows:

[0034] 1. Connect the boring bar shank of the boring bar to the spindle of the boring and milling machine, lock the key on the spindle of the boring and milling machine into the keyway of the boring bar shank, and then tighten the pull stud to fix the boring bar on the spindle of the boring and milling machine.

[0035] 2. Insert the square tool holder of the profile boring tool into the square hole of the boring tool holder, and tighten the profile boring tool by tightening the bolts. The inner spherical surface of the flange hole can then be bored. During the machining process, the depth of the inner spherical surface is controlled by the feed depth of the CNC machine tool, so that the inner spherical surface of the flange hole that meets the requirements of the drawing can be machined.

Claims

1. A tool for boring spherical surfaces inside flange holes, characterized in that, It includes a boring bar and a profile boring tool; the boring bar includes a conical boring bar shank and a rotary tool bar connected to the boring bar shank shank. The end of the boring bar shank shank is provided with a screw hole that mates with a pull stud. The rotary tool bar is provided with a square hole for mounting the profile boring tool, and one side of the square hole is provided with a bolt for fastening the profile boring tool. The aforementioned profile boring tool includes a square tool holder and a tool head located at the end of the tool holder. The tool head includes a back, a face, a main cutting edge, a secondary cutting edge, a straight cutting edge, a front side, and a rear side. The face is parallel to the top of the tool holder, and the back is located below the face. The main cutting edge is arc-shaped and fits against the spherical surface inside the flange hole. The main cutting edge is located in the middle left side of the face. One end of the main cutting edge is provided with a secondary cutting edge, which is perpendicular to the rear side. The other end of the main cutting edge is provided with a straight cutting edge, which forms a 120° angle with the front side. Chip removal grooves are provided between the main cutting edge, the secondary cutting edge, the straight cutting edge, and the face.

2. The flange bore spherical boring tool according to claim 1, characterized in that, The main cutting edge is composed of two arc segments, including a first arc segment and a second arc segment connected to the first arc segment. The first arc segment is connected to the secondary cutting edge, and the second arc segment is connected to the straight cutting edge. The diameter of the second arc segment is larger than the diameter of the first arc segment.

3. The flange bore spherical boring tool according to claim 1, characterized in that, The blade back is inclined inward, and the main cutting edge, secondary cutting edge, straight cutting edge and the blade back form an 8° angle.

4. The flange bore spherical boring tool according to claim 1, characterized in that, The aforementioned profile boring tool is made of high-speed steel M42.

5. The flange bore spherical boring tool according to claim 1, characterized in that, The taper of the boring bar shank is 7:

24.

6. The flange bore spherical boring tool according to claim 1, characterized in that, The boring bar shank has keyways on both sides that mate with the key on the boring and milling machine spindle.

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