Machining method of thin-wall mounting plate type slender blade

Abstract

The invention relates to the technical field of aviation engine blade machining, in particular to a machining method of a thin-wall mounting plate type long and thin blade, which comprises the following steps: S1, preparing a blank piece; s2, the outer contour of the blade is roughly machined, specifically, the front-view projection contour shape of the blade is machined through linear cutting, the allowance is reserved, a rough machining part composed of the mounting plate and the blade body is obtained, and a blade tip process section is cut at the tip end of the blade body during linear cutting; s3, roughly machining a blade body: roughly machining a blade basin and a blade back of the blade body on a vertical numerical control milling machine; s4, the bottom face, the peripheral side faces and the two mounting holes of the mounting plate are subjected to finish machining; s5, the mounting plate is clamped through a clamp, the mounting hole serves as a positioning reference, meanwhile, the blade tip process section is clamped through a chuck on a machine tool, the top face of the mounting plate is subjected to finish machining, and the blade basin, the blade back, the front edge and the rear edge of the blade body are subjected to finish machining; s6, a blade tip process section is cut off through linear cutting, and a remelting layer is removed; s7, polishing the blade body and the mounting plate; and S8, carrying out fluorescence detection.

Description

Technical Field

[0001] The invention relates to the technical field of aviation engine blade processing, and in particular to a processing method for thin-walled mounting plate-type slender blades. Background Art

[0002] The straightening blades are assembled in the engine casing through blade mounting plates to provide a definite direction and a stable flow of compressed air for the compressor or combustion chamber rotor blades, so that the compressor rotor blades can obtain stable working conditions and provide a stable high-pressure airflow for the combustion chamber, promoting its efficient operation.

[0003] Rectifier blades are divided into journal blades, guide window blades and mounting plate blades.

[0004] Generally, the mounting plate of the mounting plate type rectifier blade is in the shape of an arc, and is assembled into a complete circle and fixed on the casing during assembly. The main steps for processing this type of blade are: pouring low-melting-point alloy on the blade to transfer the raw material positioning reference to the alloy block, and processing the mounting plate; drilling the top hole in the blade tip process section, clamping the mounting plate and tightening the top hole, and processing the blade body and the inner side of the mounting plate. Its disadvantages are:

[0005] First, the conversion of the raw material datum is completed by pouring a low-melting-point alloy, which involves multiple conversions of the datum and has poor consistency. The processing quality of the blade surface is strongly related to the accuracy of the poured alloy, and 5 to 8 parts need to be poured for trial processing before batch pouring. This results in large errors and the risk of batch scrapping, and low processing efficiency.

[0006] Second, the top hole positioning method is not suitable for blades with thin mounting plates and slender blades. The reason is that the mounting plate is thin (less than 2 mm), the clamping area is too small, and the clamping force is insufficient. For slender and thin-walled blades, when the top hole is pressed tightly, the middle of the blade belongs to a typical weak stiffness area, which is easy to produce obvious surface vibration marks due to the coupling of cutting vibration frequency and part inherent vibration frequency, especially when the blade material is nickel-based high-temperature alloy (such as GH4169, GH4169D, GH3128, etc.), the surface vibration marks of this type of blade are more obvious. Therefore, it is necessary to study and design a processing method for slender and thin-walled blades with mounting plates. Summary of the invention

[0007] The main purpose of the present invention is to provide a method for processing thin-walled mounting plate-type slender blades, aiming to solve the above-mentioned technical problems.

[0008] To achieve the above object, the present invention provides a method for processing thin-walled mounting plate-type elongated blades, the steps comprising:

[0009] S1. Preparing a blank: the blank is a plate-shaped blank obtained after forging;

[0010] S2. Rough machining of the outer contour of the blade: Use wire cutting to machine the front projection contour shape of the blade, and leave a margin to obtain a rough machined part consisting of a mounting plate and a blade body. During wire cutting, a blade tip process section is cut at the tip of the blade body;

[0011] S3. Rough machining of blade body: Rough machining of blade basin and blade back of blade body on vertical CNC milling machine;

[0012] S4, finishing the bottom surface, surrounding sides, and two mounting holes of the mounting plate;

[0013] S5. Clamp the blade on the mounting plate with a fixture, use the mounting hole as a positioning reference, and use the chuck on the machine tool to clamp the blade tip process section, and fine-process the top surface of the mounting plate, as well as the blade basin, blade back, and leading and trailing edges of the blade body;

[0014] S6. Cut off the blade tip process section by wire cutting and remove the remelted layer;

[0015] S7, polishing blade and mounting plate;

[0016] S8. Fluorescence detection.

[0017] Preferably, in step S1, the method for preparing the blank comprises the following steps:

[0018] S101, cut the bar with a diameter of φ64mm and a length of 160mm;

[0019] S102, forging: pre-forging, final forging and heat treatment are performed on the bar material in sequence to obtain a blank with a thickness of 28 mm ± 2 mm.

[0020] Preferably, in step S102, before pre-forging, firstly, a glass lubricant with a thickness of 0.1 to 0.2 mm is sprayed on the surface of the bar; then, the bar is heated at a temperature of 1120°C ± 10°C for 29 to 50 minutes, and a pre-forging is obtained by a single forging with a 30-35MN electric screw press.

[0021] Preferably, in step S2, when rough machining the outer contour of the blade, a machining allowance of 0.5 mm is left on the bottom surface of the mounting plate and the leading and trailing edges of the blade body.

[0022] Preferably, in step S3, when rough machining the blade body, a machining allowance of 0.7 mm is left on both the blade base and the blade back of the blade body.

[0023] Preferably, in step S4, when processing the mounting plate, the following steps are included:

[0024] S401, use a ball-end milling cutter with a tool diameter of 16 mm and a blade radius of 1 mm to first rough mill the bottom surface and surrounding side surfaces of the mounting plate, and then fine mill the surrounding side surfaces;

[0025] S402, using a ball head with a tool diameter of 10 mm and a blade radius of 5 mm, firstly rough mill the groove on the bottom surface of the mounting plate, and then fine mill the bottom surface and the groove of the mounting plate;

[0026] S403, use a ball-end drill with a tool diameter of 6 mm and a blade radius of 0.2 mm to drill holes to form mounting holes;

[0027] S404. Use a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1 mm to remove burrs on the bottom surface and groove plane of the mounting plate, as well as on the surrounding side surfaces.

[0028] Preferably, in step S5, the fixture structure adopted includes an adapter, a base, a clamping block, and a stopper; the adapter is used to be installed on the turntable of the dual-drive five-axis linkage CNC machining center; the base is installed on the top surface of the adapter; a positioning base is installed on the top surface of the base; the clamping block is installed in the mounting groove of the vertical surface of the positioning base through a clamping bolt, and the top of the clamping block is higher than the top surface of the positioning base; the stopper is installed on the top surface of the positioning base; two supporting columns are arranged on the top surface of the positioning base, and a vertical positioning pin is inserted into one of the supporting columns; in step S5, when the fixture clamps the mounting plate, it is supported on the bottom surface of the mounting plate by two supporting columns, and the positioning pin is inserted in a mounting hole of the mounting plate, and one of the long side surfaces of the mounting plate abuts against the vertical side surface of the stopper; tighten the clamping bolt so that the upper end of the clamping block is pressed against the other long side surface of the mounting plate.

[0029] Preferably, a clamping boss is provided on the clamping block, and the clamping boss is used to clamp on the long side of the mounting plate; a hemispherical block is provided on the side of the clamping block near the lower edge, and the hemispherical block is located directly below the clamping boss, and the hemispherical block rests on the bottom of the mounting groove.

[0030] Preferably, a spring is provided on the outer sleeve of the clamping bolt, one end of the spring abuts against the bottom of the mounting groove, and the other end abuts against the clamping block.

[0031] Preferably, step S5 comprises the following sub-steps:

[0032] S501, using a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1.5 mm, the blade body is subjected to rough machining, semi-rough machining and fine machining in sequence;

[0033] S502, use a ball-end cutter with a tool diameter of 6 mm and a blade radius of 3 mm to perform rough machining on the top surface of the mounting plate and semi-fine cleaning on the root of the blade body;

[0034] S503. Use a ball-end cutter with a tool diameter of 6 mm and a blade radius of 2 mm to finish the top surface of the mounting plate and clean the root of the blade to size.

[0035] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0036] (1) The present invention provides a method for processing thin-walled mounting plate-type slender blades, which changes the traditional method of converting the mounting plate-type blades by casting low-melting-point alloys, further reduces the risk of batch scrapping, shortens the development cycle of mounting plate-type blades, and greatly improves the processing efficiency of such blades.

[0037] (2) In the clamp used in the present invention, when the clamping bolt is tightened for clamping, the upper end of the clamping block is pressed against the long side surface of the mounting plate to form a surface contact state, ensuring that when the clamp clamps the blade, the line contact state in the traditional clamping state is changed to the surface contact state, so that the originally thin mounting plate has a more stable and reliable clamping force, solving the problems of insufficient clamping force of slender thin-walled blades with holes in the mounting plate and serious tool vibration during milling, effectively improving the vibration marks on the blade surface, and greatly reducing the scrap rate of this type of blades during blade body processing.

[0038] (3) In the present invention, by setting a blade tip process section, when the blade base and blade back of the blade body are finely processed, a clamp is used to clamp it on the mounting plate, and the mounting hole is used as a positioning reference. At the same time, the blade tip process section is clamped by a chuck on a machine tool, which plays a good clamping role for the entire blade, thereby overcoming the problem of surface vibration marks generated when the top hole is used to tighten in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0040] Figure 1 It is a schematic diagram of the structure of the blank;

[0041] Figure 2 This is the main view of the blade when the blade tip process section is not cut off;

[0042] Figure 3 This is a top view of the blade when the blade tip section is not cut off;

[0043] Figure 4 It is a schematic diagram of the structural decomposition of the blade and the fixture;

[0044] Figure 5 It is a schematic diagram of the assembly of the clamping block, the clamping bolt and the spring on the fixture;

[0045] Figure 6 It is a structural schematic diagram of the compression block in the present invention.

[0046] Explanation of the accompanying drawings: 1. Adapter; 2. Base; 3. Clamping block; 301. Hemispherical block; 302. Clamping boss; 4. Support column; 5. Stopper; 6. Locating pin; 7. Clamping bolt; 8. Positioning base; 8a. Mounting groove; 9. Spring; 100. Blank; 201. Mounting plate; 202. Blade body; 203. Blade tip process section. DETAILED DESCRIPTION

[0047] 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.

[0048] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0049] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0050] Combination Figures 1 to 6 As shown, a method for processing thin-walled mounting plate-type elongated blades comprises the following steps:

[0051] S1. Prepare a blank 100: The blank 100 is a plate-shaped blank obtained after forging.

[0052] S2, rough machining of the outer contour of the blade: the front projection contour of the blade is machined by wire cutting, and a margin is left to obtain a rough machined part consisting of the mounting plate 201 and the blade body 202. During wire cutting, a blade tip process section 203 is cut at the tip of the blade body 202. By setting the blade tip process section 203, a clamping position is provided for the blade body 202 when it is machined.

[0053] S3. Rough machining of the blade body 202: rough machining of the blade base and blade back of the blade body 202 on a vertical CNC milling machine.

[0054] S4. Finish the bottom surface, surrounding side surfaces, and two mounting holes of the mounting plate 201.

[0055] S5. Use a fixture to clamp the blade on the mounting plate 201, and use the mounting hole as a positioning reference. At the same time, use the chuck on the machine tool to clamp the blade tip process section 203, and fine-process the top surface of the mounting plate 201, as well as the blade basin, blade back and leading and trailing edges of the blade body 202.

[0056] S6. After the profile of the blade body 202 and the top surface P of the mounting plate 201 are processed, the blade tip process section 203 is cut off by wire cutting, and the remelted layer is removed. Specifically, the thickness of the remelted layer after wire cutting is 0.003-0.008 mm, that is, the remelted layer can be completely removed by trimming the excess of 0.02-0.03 mm.

[0057] S7, polishing blade and mounting plate;

[0058] S8. Fluorescence testing: Use fluorescence penetration testing to inspect the finished blades and finally obtain qualified blades.

[0059] In step S1, the method for preparing the blank 100 includes the following steps:

[0060] S101, cut the bar with a diameter of φ64mm and a length of 160mm;

[0061] S102, forging: pre-forging, final forging and heat treatment are performed on the bar material in sequence to obtain a blank 100 with a thickness of 28 mm±2 mm.

[0062] In this embodiment, in step S102, before pre-forging, firstly, a glass lubricant with a thickness of 0.1 to 0.2 mm is sprayed on the surface of the bar material; then, the bar material is heated at a temperature of 1120°C ± 10°C for 29 to 50 minutes, and a pre-forging is obtained by a single forging with a 30-35MN electric screw press.

[0063] In this embodiment, in step S2, when the outer contour of the blade is roughly machined, a machining allowance of 0.5 mm is left on the bottom surface D of the mounting plate 201 and the leading edge E and the trailing edge F of the blade body 202.

[0064] In this embodiment, in step S3, when the blade body 202 is roughly processed, a processing allowance of 0.7 mm is left on the blade base and the blade back of the blade body 202.

[0065] In this embodiment, when processing the mounting plate 201, step S4 includes the following steps:

[0066] S401, using a ball-end milling cutter with a tool diameter of 16 mm and a blade radius of 1 mm, firstly rough milling the bottom surface D and the surrounding side surfaces of the mounting plate 201, and then fine milling the surrounding side surfaces;

[0067] S402, using a ball head with a tool diameter of 10 mm and a blade radius of 5 mm, firstly rough milling the groove on the bottom surface D of the mounting plate 201, and then fine milling the bottom surface D and the groove of the mounting plate 201.

[0068] S403, use a ball-end drill with a tool diameter of 6 mm and a blade radius of 0.2 mm to drill holes to form mounting holes M and N;

[0069] S404, using a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1 mm to remove burrs on the bottom surface D of the mounting plate 201 and the groove plane, and to remove burrs on the surrounding side surfaces.

[0070] Combination Figure 4 As shown, in the step S5, the fixture structure used includes an adapter 1, a base 2, a clamping block 3, and a stopper 5; the adapter 1 is used to be installed on the turntable of the dual-drive five-axis linkage CNC machining center; the base 2 is installed on the top surface of the adapter 1; a positioning base 8 is installed on the top surface of the base 2; the clamping block 3 is installed in the mounting groove 8a of the vertical surface of the positioning base 8 through a clamping bolt 7, and the top of the clamping block 3 is higher than the top surface of the positioning base 8; the stopper 5 is installed on the top surface of the positioning base 8; two supporting columns 4 are arranged on the top surface of the positioning base 8, and a vertical positioning pin 6 is inserted into one of the supporting columns 4.

[0071] Combination Figures 2 to 4 As shown, by adopting the above-mentioned clamp, in the step S5, when the clamp clamps the mounting plate 201, two support columns 4 are used to support the bottom surface D of the mounting plate 201, and the positioning pin 6 is inserted into the mounting hole N of the mounting plate 201, and one of the long side surfaces A of the mounting plate 201 is against the vertical side surface of the stopper 5; tighten the clamping bolt 7 so that the upper end of the clamping block 3 is pressed against the other long side surface B of the mounting plate 201. The mounting plate 201 can be clamped and positioned. After the clamping is completed, the blade basin and blade back of the blade body 202 are inspected, and the tolerance runout from the blade tip to the blade root is required to be no more than 0.02mm.

[0072] Combination Figure 6 As shown, the clamping block 3 is provided with a clamping boss 302, and the clamping boss 302 is used to clamp on the long side surface of the mounting plate 201; a hemispherical block 301 is provided on the side surface of the clamping block 3 near the lower edge, and the hemispherical block 301 is located directly below the clamping boss 302, and the hemispherical block 301 abuts against the bottom of the mounting groove 8a. The clamping block 3 forms a lever structure by using the clamping boss 302 and the hemispherical block 301. When the clamping bolt 7 is tightened, the hemispherical block 301 plays a supporting role, so that the clamping boss 302 is pressed tightly on the long side surface B of the mounting plate 201.

[0073] Combination Figure 5 A spring 9 is disposed on the outer sleeve of the clamping bolt 7, one end of the spring 9 abuts against the bottom of the mounting groove 8a, and the other end abuts against the clamping block 3. The spring 9 is always in a compressed energy storage state. When the clamping bolt 7 is loosened, the clamping block 3 is ejected under the action of the spring 9, and the mounting plate 201 can be quickly loosened.

[0074] In this embodiment, step S5 includes the following sub-steps:

[0075] S501, using a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1.5 mm, the blade body 202 is subjected to rough machining, semi-rough machining and fine machining in sequence;

[0076] S502, using a ball-end cutter with a tool diameter of 6 mm and a blade radius of 3 mm, rough-processing the top surface of the mounting plate 201 and semi-fine cleaning the root of the blade body 202;

[0077] S503, using a ball-end cutter with a tool diameter of 6 mm and a blade radius of 2 mm, the top surface of the mounting plate 201 is finely processed, and the root of the blade body 202 is cleaned to size.

[0078] After the processing in step S5 is completed, the profile data of the blade body 202 is detected by three-coordinate measurement.

[0079] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for processing thin-walled mounting plate-type elongated blades, characterized in that the steps include: S1. Preparing a blank (100): the blank (100) is a plate-shaped blank obtained after forging; S2. Rough machining of the outer contour of the blade: using wire cutting to machine the front projection contour of the blade, leaving a margin, to obtain a rough machined part consisting of a mounting plate (201) and a blade body (202), and cutting a blade tip process section (203) at the tip of the blade body (202) during wire cutting; S3, rough machining of the blade body (202): rough machining of the blade base and blade back of the blade body (202) on a vertical CNC milling machine; S4, finely processing the bottom surface, surrounding side surfaces, and two mounting holes of the mounting plate (201); S5, clamping the blade on the mounting plate (201) with a fixture, using the mounting hole as a positioning reference, and clamping the blade tip process section (203) with a chuck on a machine tool, and fine-machining the top surface of the mounting plate (201), as well as the blade basin, blade back, and leading and trailing edges of the blade body (202); S6, cutting off the blade tip process section (203) by wire cutting, and removing the remelted layer; S7, polishing blade and mounting plate; S8. Fluorescence detection.

2. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: In step S1, the method for preparing the blank (100) comprises the following steps: S101, cut the bar with a diameter of φ64mm and a length of 160mm; S102, forging: pre-forging, final forging and heat treatment are performed on the bar material in sequence to obtain a blank (100) with a thickness of 28 mm±2 mm.

3. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 2, characterized in that: In step S102, before pre-forging, firstly, a glass lubricant with a thickness of 0.1 to 0.2 mm is sprayed on the surface of the bar material; then, the bar material is heated at a temperature of 1120°C ± 10°C for 29 to 50 minutes, and a pre-forging is obtained by a single forging with a 30-35MN electric screw press.

4. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: In the step S2, when the outer contour of the blade is roughly machined, a machining allowance of 0.5 mm is left on the bottom surface of the mounting plate (201) and the front and rear edges of the blade body (202).

5. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: In the step S3, when the blade body (202) is roughly processed, a processing allowance of 0.7 mm is left on the blade base and the blade back of the blade body (202).

6. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: In step S4, when processing the mounting plate (201), the following steps are included: S401, using a ball-end milling cutter with a tool diameter of 16 mm and a blade radius of 1 mm, firstly rough milling the bottom surface and the surrounding side surfaces of the mounting plate (201), and then fine milling the surrounding side surfaces; S402, using a ball head with a tool diameter of 10 mm and a blade radius of 5 mm, firstly rough milling the groove on the bottom surface of the mounting plate (201), and then fine milling the bottom surface and the groove of the mounting plate (201); S403, use a ball-end drill with a tool diameter of 6 mm and a blade radius of 0.2 mm to drill holes to form mounting holes; S404, using a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1 mm to remove burrs on the bottom surface and the groove plane of the mounting plate (201), and to remove burrs on the surrounding side surfaces.

7. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: In the step S5, the fixture structure used includes an adapter (1), a base (2), a clamping block (3), and a stopper (5); the adapter (1) is used to be installed on the turntable of a dual-drive five-axis linkage CNC machining center; the base (2) is installed on the top surface of the adapter (1); a positioning base (8) is installed on the top surface of the base (2); the clamping block (3) is installed in the mounting groove (8a) of the vertical surface of the positioning base (8) through a clamping bolt (7), and the top of the clamping block (3) is higher than the top surface of the positioning base (8); the stopper (5) is installed on the top surface of the positioning base (8); two supporting columns (4) are arranged on the top surface of the positioning base (8), and a vertical positioning pin (6) is inserted into one of the supporting columns (4); In step S5, when the clamp clamps the mounting plate (201), the two supporting columns (4) are used to support the bottom surface of the mounting plate (201), and the positioning pin (6) is inserted into a mounting hole of the mounting plate (201), and one of the long side surfaces of the mounting plate (201) is against the vertical side surface of the stop block (5); the clamping bolt (7) is tightened so that the upper end of the clamping block (3) is pressed against the other long side surface of the mounting plate (201).

8. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 7, characterized in that: The pressing block (3) is provided with a pressing boss (302), and the pressing boss (302) is used to press on the long side surface of the mounting plate (201); A hemispherical block (301) is arranged on the side of the clamping block (3) near the lower edge. The hemispherical block (301) is located directly below the clamping boss (302). The hemispherical block (301) abuts against the bottom of the mounting groove (8a).

9. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 7, characterized in that: A spring (9) is provided on the outer sleeve of the clamping bolt (7), one end of the spring (9) abuts against the bottom of the mounting groove (8a), and the other end abuts against the clamping block (3).

10. A method for processing thin-walled mounting plate-type elongated blades as claimed in claim 1, characterized in that: The step S5 comprises the following sub-steps: S501, using a ball-end cutter with a tool diameter of 12 mm and a blade radius of 1.5 mm, to sequentially perform rough machining, semi-rough machining and fine machining on the blade body (202); S502, using a ball-end cutter with a cutter diameter of 6 mm and a blade radius of 3 mm, rough-processing the top surface of the mounting plate (201) and semi-fine cleaning the root of the blade body (202); S503, using a ball-end cutter with a cutter diameter of 6 mm and a blade radius of 2 mm, the top surface of the mounting plate (201) is finely processed, and the root of the blade body (202) is cleaned to size.

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