Effective control methods to prevent coating chipping during the processing of oblique tooth ferrules

Abstract

This invention provides an effective control method for preventing coating peeling during the machining of oblique fang teeth, comprising the following steps: S1, optimizing the machining of the oblique fang teeth before spraying individual parts; S2, spraying the machined fang tooth structure of individual parts; S3, assembling the components after machining the individual parts; S4, after assembly, repairing the tooth tip dimensions on the components by machining the tooth tip coating of the oblique fang teeth to meet the mating dimensional requirements of the tooth tip. This invention improves the local structure of the tooth tip, thereby changing the morphological characteristics of the tooth tip coating after spraying, which is beneficial for resisting cutting forces and reducing the impact of cutting forces. Matching optimized cutting parameters can effectively avoid coating peeling caused by excessive cutting forces or rapid impact of cutting forces. It solves the problems of non-grinding and coating peeling caused by structural limitations.

Description

Technical Field

[0001] This invention relates to the field of machining oblique comb tooth parts, and particularly to a control method for effectively preventing the coating of oblique comb teeth from chipping during machining. Background Technology

[0002] In aero engines, sealing structures are often required in many areas to maintain airflow performance. A sealing grate structure with a wear-resistant coating formed by plasma spraying plays a crucial role in this process. The grate is typically sprayed after individual machining, and to ensure proper assembly clearance control, the coating on the tooth tips is usually machined onto the assembly to guarantee dimensional and runout requirements.

[0003] During this process, due to the limitations of the assembly structure of the parts, it is usually impossible to grind the coating on the top of the tooth; it can only be machined by turning. Figure 1 This is a schematic diagram of the structure of a sealing tooth in the prior art. (Example:) Figure 1 As shown, the sealing grating adopts a sealing oblique grating structure. Because the grating is an oblique structure, it is easily affected by the cutting force during the turning process, which causes the coating on one side of the grating to peel off, resulting in the phenomenon of chipping after turning.

[0004] Sealing grating structures are widely used in aircraft engine rotor components, primarily for airflow control to meet aerodynamic performance requirements. For example... Figure 2 The grating teeth shown are inclined and have a certain angle design. To increase their sealing and wear resistance, a wear-resistant coating is usually sprayed onto the surface of the grating teeth.

[0005] The tooth tip and lateral side are the areas requiring spraying, meaning a complete coating is essential. While grinding is typically used for coating the tooth tip, structural limitations necessitate turning. For example, when the sealing ring is assembled between two stages of components, the limited space makes grinding with a grinding wheel difficult.

[0006] Figure 2 This is a schematic diagram showing the stress conditions during machining and the areas where the coating has peeled off. (Example) Figure 2 As shown, plasma-sprayed wear-resistant coatings are easily affected by single-point cutting forces during turning, causing coating chips at the edges.

[0007] In view of this, the inventors of this application have designed an effective control method to prevent the coating of oblique comb teeth from chipping during processing, in order to overcome the above-mentioned technical problems. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to overcome the defects in the prior art, such as the small processing space of the oblique tooth coating, the difficulty in grinding with a grinding wheel, and the easy peeling of the coating, and to provide an effective control method to prevent the coating of oblique teeth from peeling off during processing.

[0009] The present invention solves the above-mentioned technical problems through the following technical solution:

[0010] A method for effectively preventing coating spalling during the processing of oblique tooth ferrules, characterized in that the method includes the following steps:

[0011] S1. Complete the machining optimization of the oblique serrations before spraying individual parts;

[0012] S2. Apply a spray coating to the tooth structure of a single machined part;

[0013] S3. After individual parts are processed, components are assembled.

[0014] S4. After assembly, the tooth tip dimensions are repaired on the component. The tooth tip coating of the oblique grating is machined to meet the mating dimension requirements of the grating tooth tip.

[0015] According to an embodiment of the present invention, step S1 further includes: straightening the sharp corner on one side of the oblique comb tip to form an oblique cut surface.

[0016] According to one embodiment of the present invention, the width of the bevel is 0.2 mm.

[0017] According to one embodiment of the present invention, the machining tool for finishing the comb teeth in step S4 is a 35° angled diamond insert with a radius of 0.8 mm.

[0018] According to one embodiment of the present invention, the machining tool is matched with a linear velocity of less than 30 m / s, a finishing depth of cut of less than 0.08 mm, and a feed rate of less than 0.1 mm / r in the cutting parameters.

[0019] According to one embodiment of the present invention, the linear speed is 25 m / s, the depth of cut is 0.05 mm, and the feed rate is 0.08 mm / r.

[0020] According to one embodiment of the present invention, in step S4, during the initial cutting, the depth of cut is mainly determined by the finishing cut after tool setting confirmation.

[0021] According to one embodiment of the present invention, the cutting depth of the blade is 0.02 mm to 0.03 mm.

[0022] According to one embodiment of the present invention, in step S4, after the first machining operation, the parameters and tools used during the first machining operation are maintained and machining is performed.

[0023] The positive and progressive effects of this invention are as follows:

[0024] This invention provides an effective control method for preventing coating chipping during the processing of oblique tooth ferrules. Based on a redesigned ferrule structure, it offers the following numerous advantages:

[0025] 1. Improve the local structure of the tooth tip to change the morphology of the coating on the tooth tip after spraying, which is beneficial to resist cutting force and reduce the impact of cutting force;

[0026] Second, matching and optimizing cutting parameters can effectively avoid coating peeling caused by excessive cutting force or rapid impact of cutting force;

[0027] Third, it solved the problems of inability to grind due to structural limitations and coating peeling. Attached Figure Description

[0028] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always denote the same features, wherein:

[0029] Figure 1 This is a schematic diagram of the structure of a sealing tooth in the prior art.

[0030] Figure 2 A schematic diagram showing the stress conditions during machining and the areas where the coating has peeled off.

[0031] Figure 3 This is a schematic diagram of the optimized structure of the oblique comb tooth tip in the control method for effectively preventing coating chipping during the processing of oblique comb teeth according to the present invention.

[0032] Figure 4 This is a schematic diagram illustrating the effect of spraying oblique fangs after coating, in the control method of the present invention for effectively preventing the coating from chipping during the processing of oblique fangs.

[0033] Figure 5 This is a schematic diagram of the component turning (which can be reverse-processed) in the control method for effectively preventing the coating of oblique teeth from chipping during processing, as described in this invention. Detailed Implementation

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] Embodiments of the invention will now be described in detail with reference to the accompanying drawings. Preferred embodiments of the invention will now be described in detail, examples of which are shown in the drawings. Wherever possible, the same reference numerals will be used in all the drawings to denote the same or similar parts.

[0036] Furthermore, although the terminology used in this invention is selected from commonly known and used terms, some terms mentioned in this specification may have been selected by the applicant in his or her judgment, and their detailed meanings are explained in the relevant sections of the description herein.

[0037] Furthermore, the invention should be understood not only through the actual terminology used, but also through the meaning implied by each term.

[0038] Figure 3 This is a schematic diagram of the optimized structure of the oblique comb tooth tip in the control method for effectively preventing coating chipping during the processing of oblique comb teeth according to the present invention. Figure 4 This is a schematic diagram illustrating the effect of spraying oblique fangs after coating, in the control method of the present invention for effectively preventing the coating from chipping during the processing of oblique fangs. Figure 5 This is a schematic diagram of the component turning (which can be reverse-processed) in the control method for effectively preventing the coating of oblique teeth from chipping during processing, as described in this invention.

[0039] like Figures 3 to 5 As shown, this invention discloses an effective method for controlling the spalling of coatings during the processing of oblique ferrules, which includes the following steps:

[0040] S1. Complete the machining optimization of the oblique serrations before spraying individual parts.

[0041] Preferably, step S1 further includes: straightening one side of the pointed corner of the oblique tooth 10 to form an oblique cut surface 11. The width of the oblique cut surface 11 is 0.2 mm.

[0042] like Figure 3 As shown, the sharp corner on one side of the oblique tooth 10 is treated with a straight surface. According to the results determined by the test plan, the optimal straight surface width d≈0.2mm is the best. If it is too narrow, it will not achieve a good coating bonding effect, and if it is too large, it will change the sealing effect of the tooth.

[0043] S2. Apply a spray coating to the tooth structure of a single machined part.

[0044] Before spraying, complete the process test according to the engineering drawings to ensure that the adhesion of the coating meets the standard requirements during the spraying process, and that the tooth shape after spraying is as follows. Figure 4 As shown.

[0045] S3. After individual parts are processed, components are assembled.

[0046] S4. After assembly, the tooth tip dimensions are repaired on the component. The tooth tip coating of the oblique grating is machined to meet the mating dimension requirements of the grating tooth tip.

[0047] Preferably, in step S4, the machining tool 20 for finishing the ferrules uses a 35° angled diamond insert with a radius of 0.8 mm. The machining tool 20 is matched with a linear velocity Vs less than 30 m / s, a depth of cut ap less than 0.08 mm, and a feed rate f less than 0.1 mm / r in its cutting parameters.

[0048] Furthermore, the optimal matching option is that the linear velocity Vs is 25 m / s, the depth of cut ap is 0.05 mm, and the feed rate f is 0.08 mm / r.

[0049] Due to the influence of adhesion on the coating, during finishing, the linear velocity Vs of the cutting tool should not exceed 30 m / s, the depth of cut ap should not exceed 0.08 mm, and the feed rate f should not exceed 0.1 mm / r. Furthermore, new tools must be used during machining to ensure sufficient sharpness, and the tool path should be as follows: Figure 5 As shown.

[0050] Specifically, in step S4, during the initial cutting, after confirming the tool, the depth of cut ap is primarily for finishing. Alternatively, the depth of cut is controlled between 0.02 mm and 0.03 mm.

[0051] In step S4, after the initial cutting, maintain the parameters and tool used during the initial cutting. Furthermore, the tool must not be changed during the final cutting. If the tool is changed, the finishing and re-cutting operations (with the depth of cut ap performed as described above) should be repeated at least twice.

[0052] In addition, no cutting fluid shall be used for cooling during the entire cutting process, the machine tool ratio shall not be adjusted to increase or decrease cutting efficiency, and rework tools or worn tools shall not be used.

[0053] Visually inspect the appearance of the processed fangs; there are no defects such as chipping or detachment on the surface.

[0054] Based on the above description, this invention provides an effective control method for preventing coating chipping during the machining of oblique fang teeth. It relates to a plasma spraying coating processing method for the tips of metal fang teeth, focusing on the machining of parts containing oblique fang teeth to solve the problem of coating chipping at the edges of the fang teeth tips caused by conventional machining. Specifically, to address the problem of coating chipping during machining of oblique fang teeth, a feasible fang tooth structure design and machining method are proposed. The control method involves a minor modification to the top structure of the oblique fang teeth. A straight edge improvement design is applied to the left fang tooth tip, with a straight edge width d≈0.2mm, which has no impact on the functionality of the fang teeth (e.g., ...). Figure 3 (As shown). The purpose of this design is to transform the weak-resistance zone of the fang teeth into a strong-resistance zone after the coating is applied, thereby changing the morphology of the coating after deposition (e.g., Figure 4 (As shown). Simultaneously, the machining parameters were standardized: Through testing, the optimal cutting parameters were determined to be a 35° rhomboid insert with a radius of 0.8, a linear speed of Vs = 25 m / s, a depth of cut ap = 0.05 mm, and a feed rate f = 0.08 mm / r. This combination of methods effectively prevents coating peeling during machining of the helical tooth coating.

[0055] In summary, the present invention provides an effective control method for preventing coating chipping during the processing of oblique tooth ferrules, based on a redesigned tooth structure and offering the following numerous advantages:

[0056] 1. Improve the local structure of the tooth tip to change the morphology of the coating on the tooth tip after spraying, which is beneficial to resist cutting force and reduce the impact of cutting force;

[0057] Second, matching and optimizing cutting parameters can effectively avoid coating peeling caused by excessive cutting force or rapid impact of cutting force;

[0058] Third, it solved the problems of inability to grind due to structural limitations and coating peeling.

[0059] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for effectively preventing coating chipping during the processing of oblique ferrules, characterized in that, The effective control method for preventing coating chipping during the processing of oblique comb teeth includes the following steps: S1. Before spraying individual parts, complete the processing optimization of the oblique fang teeth, and straighten the sharp corner on one side of the oblique fang teeth to form an oblique cut surface; S2. Apply a spray coating to the tooth structure of a single machined part; S3. After individual parts are processed, components are assembled. S4. After assembly, the tooth tip dimensions are repaired on the component. The tooth tip coating of the oblique grating is machined to meet the mating dimension requirements of the grating tooth tip.

2. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 1, characterized in that, The width of the beveled surface is 0.2 mm.

3. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 1, characterized in that, In step S4, the machining tool for finishing the comb teeth is a 35° angled diamond-shaped insert with a radius of 0.8 mm.

4. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 3, characterized in that, The machining tool is matched with a cutting parameters in which the linear velocity is less than 30m / s, the depth of cut is less than 0.08mm, and the feed rate is less than 0.1mm / r.

5. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 4, characterized in that, The linear speed is 25 m / s, the depth of cut is 0.05 mm, and the feed rate is 0.08 mm / r.

6. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 1, characterized in that, In step S4, during the initial machining process, the depth of cut is primarily determined by the finishing cut after tool setting confirmation.

7. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 6, characterized in that, The cutting depth of the tool is 0.02 mm to 0.03 mm.

8. The control method for effectively preventing coating chipping during the processing of oblique ferrules as described in claim 6, characterized in that, In step S4, after the initial machining, the parameters and tools used during the initial machining are maintained for further machining.

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