Laser cladding repairing method for damage of inner ring of flame tube swirler of aero-engine

Abstract

The invention provides a laser cladding repairing method for damage of an inner ring of a flame tube swirler of an aero-engine in order to effectively repair the damage of the inner ring of the flame tube swirler of the aero-engine. Firstly, the structure of an existing coaxial powder feeding device in laser cladding repairing equipment is improved into the lateral powder feeding device with the height and the angle of the powder feeding pipe adjustable, the lateral powder feeding device enables the powder feeding direction to be changed through the powder feeding pipe with the angle adjustable, and therefore a powder discharging path is separated from a light discharging path; powder is conveyed to the surface to be repaired from the side face under the condition that a laser light path is not interfered. Secondly, the diameter of a powder outlet hole of a powder feeding pipe of the lateral powder feeding device is designed to be 1mm, so that the powder can uniformly cover a cladding surface, the flatness of the cladding surface is ensured, and the problem that the uniformity of powder bundles is poor in the non-vertical powder feeding process of the lateral powder feeding device is solved; and finally, by optimizing laser cladding process parameters, the adaptation degree of powder for cladding and a base body is improved, the deformation amount of the inner ring is controlled, and the performance index of the repaired swirler inner hole is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of laser cladding, and in particular to a laser cladding repair method for damage to an inner ring of a vortex flowmeter of an aircraft engine flame tube. Background Art

[0002] The working environment of aircraft engine flame tubes is characterized by high temperature and high pressure. The inner ring of the vortex finder is easily damaged by ablation and wear due to the high temperature airflow. During the fault inspection, it was found that the wear degree of the inner ring of some flame tube vortex finders exceeded the process requirements. The damaged parts on the inner ring of the flame tube vortex finder need to be restored to meet the process requirements.

[0003] The damage to the inner ring of the flame tube vortex flowmeter is shown in Figure 1 . Since the diameter of the inner ring of the flame tube vortex flow generator is small, the thickness of the ring wall after damage is generally less than 0.7mm, which is a typical annular thin-walled part. The traditional welding repair method is limited by the size of the equipment. The welding gun is difficult to reach the damaged part of the inner hole wall of the inner ring of the flame tube vortex flow generator. At the same time, the heat input of traditional welding is large, and the repair of thin-walled parts is very easy to deform, which cannot meet the size requirements of the inner ring of the flame tube vortex flow generator. Therefore, the traditional welding repair method cannot repair this type of fault.

[0004] Laser cladding technology has a fast laser heating speed and little thermal damage to the base material. It can restore the mechanical properties of damaged parts to the maximum extent. The cladding location is precise, and after a small amount of subsequent processing, the repaired parts can meet the use requirements. However, there are the following technical difficulties when using laser repair methods to repair the inner ring damage of the flame tube vortexer:

[0005] First, the inner hole wall of the flame tube vortexer is deeply damaged and has a small aperture. The conventional repair method is the powder-light coaxial repair method. In this method, the powder output path is consistent with the light output path, but the damaged part of the flame tube vortexer is the inner ring. The powder-light coaxial method will cause the laser light path to be blocked when the powder reaches the area to be clad, and the inner hole cannot be repaired. When the laser light path reaches the area to be clad, the powder cannot reach the surface to be repaired. Therefore, the first difficulty in the entire repair process is to consider how to separate the powder output path and the light output path, and to ensure that the laser delivers the repair powder to the surface point to be repaired under normal light output conditions.

[0006] Secondly, the repair surface is not a simple external plane as usual, but an internal annular surface of different shapes. The defocus amount is in a real-time changing state during the repair process. How to ensure that the laser cladding head can evenly feed the powder to the cladding surface is the second difficulty.

[0007] Finally, since the inner ring wall of the flame tube vortexer is thin, the thickness of some surfaces to be repaired is less than 0.3 mm, and the cladding process window is narrow, how to adjust the laser cladding process parameters to control the deformation of thin-walled workpieces is the third difficulty.

[0008] Therefore, it is difficult to effectively repair the damage to the inner ring of the flame tube vortex flower by directly using the existing publicly available laser repair method. It is urgent to study and find a laser cladding repair method for repairing the damage to the inner ring of the flame tube vortex flower so that it can meet the process requirements after repair. Summary of the invention

[0009] In order to effectively repair the damage of the inner ring of the flame liner swirler, the present invention proposes a laser cladding repair method for the damage of the inner ring of the flame liner swirler of an aircraft engine.

[0010] The technical solution of the present invention is:

[0011] A laser cladding repair method for the damaged inner ring of a vortex flow tube of an aircraft engine is special in that it comprises the following steps:

[0012] Step 1: Grind and clean the surface to be repaired;

[0013] Step 2: Improve the coaxial powder feeding device in the laser cladding repair equipment to a lateral powder feeding device with adjustable height and angle of the powder feeding tube, and the diameter of the powder outlet hole of the improved powder feeding tube is 1 mm, and then adjust the height and angle of the powder feeding tube in the lateral powder feeding device;

[0014] Step 3: Formulate laser cladding repair process and select laser cladding repair process parameters; process parameters are selected from the following parameter range: laser power: 200-500w; scanning speed: 150-300mm / min; spot diameter: 1mm; powder feeding rate: 0.6-1.0r / min; pulse mode: pulse width 15-18; frequency 20-25; duty cycle 40-45%; defocus: 2-6mm;

[0015] Step 4: using a dried nickel-chromium alloy powder with a particle size of 100-200 μm as a powder for repair, using a fiber laser, according to the laser cladding repair process and process parameters formulated in step 3, and using the lateral powder feeding device to perform laser cladding repair on the inner ring of the flame tube vortexer to be repaired by lateral powder feeding;

[0016] Step 5: Re-reaming the surface of the cladding layer of the inner ring of the flame tube vortexer repaired by laser cladding;

[0017] Step 6: Repair quality inspection;

[0018] Step 6.1: metallographic analysis is performed on the cladding layer on the inner ring of the flame tube vortexer after repair. If the cladding layer has no cracks, no fusion, or pore defects, the process proceeds to step 6.2. If the cladding layer has cracks, no fusion, or pore defects, the cladding layer is re-polished and the process returns to step 3 above until it is confirmed that the cladding layer in the repaired area of ​​the flame tube vortexer inner hole has no cracks, no fusion, or pore defects, and then the process proceeds to step 6.2.

[0019] Step 6.2 Fluorescent flaw detection inspection;

[0020] Perform fluorescent flaw detection on the inner ring wall of the repaired flame tube vortex flower to determine whether there are cracks or pore defects; if there are defects, re-grind the cladding layer and return to the above step 3 until it is confirmed that the fluorescent flaw detection results of the repaired area of ​​the flame tube vortex flower inner hole show no cracks or pore defects, and then proceed to step 6.3;

[0021] Step 6.3 Dimensional inspection;

[0022] The dimensions of the inner ring of the repaired flame tube vortexer are inspected. If there is no deformation or deviation, the part is qualified for repair; if there is deformation and deviation, but it does not exceed the size requirement, the part is qualified for repair; if there is deformation and deviation and it exceeds the size requirement, the part can only be scrapped.

[0023] Furthermore, the lateral powder feeding device described in step 2 is improved on the basis of the structure of the original coaxial powder feeding device by the following method:

[0024] First, remove the powder feeding pipe in the original coaxial powder feeding device;

[0025] Then, the powder delivery pipe is redesigned and manufactured. The diameter of the powder outlet of the new powder delivery pipe is 1mm. The upper outer diameter is large for easy clamping, and the lower outer diameter is less than or equal to 3mm to extend into the inner ring of the vortex flow device to ensure that the powder is delivered to the surface to be repaired.

[0026] Next, a fixture for clamping a new powder delivery pipe is designed and manufactured. The angle is composed of an angle adjustment mechanism and a height adjustment mechanism. The new powder delivery pipe is installed on the angle adjustment mechanism, which is installed on the height adjustment mechanism. The height adjustment mechanism is installed on the pad in the original coaxial powder delivery device.

[0027] At the same time, the cooling water circuit and the restraining gas circuit in the original coaxial powder feeding device are omitted, and the structure and connection relationship of the other components in the original coaxial powder feeding device remain unchanged;

[0028] Finally, a new powder delivery pipe is installed on the cushion block through a clamp, and the upper end of the new powder delivery pipe is connected to the powder barrel through a powder path;

[0029] At this point, the lateral powder feeding device is obtained.

[0030] Furthermore, the method for formulating the laser cladding repair process in step 3 is specifically as follows: determine the repair area according to the damage condition of the inner ring of the flame tube vortexer, determine the number of layers and passes required to be overlapped during cladding according to the repair area, determine the starting and ending points of the cladding, and plan the scanning path.

[0031] Furthermore, in step 4, nickel-chromium alloy powder with a particle size of 110-130 μm is used as the powder for repairing. Before cladding, the nickel-chromium alloy powder is placed in a vacuum drying oven at 90-130° C. and dried for 1-4 hours to ensure that the powder is dry.

[0032] Furthermore, in step 4, when performing laser cladding repair, the thickness of the cladding layer is made higher than the substrate surface of the area to be repaired, and during the cladding process of the same layer, the distance between the laser beam focus and the cladding base surface is kept fixed, and the fixed height is 4 mm.

[0033] Furthermore, in step 5, the flame tube vortex finder is fixed on a vertical drilling machine according to the flame tube vortex finder design drawing and relevant technical requirements, and the surface of the cladding layer of the inner ring of the flame tube vortex finder repaired by laser cladding is re-reamed using the vertical drilling machine.

[0034] Beneficial effects of the present invention:

[0035] Compared with the prior art, the present invention firstly changes the structure of the existing coaxial powder feeding device in the laser cladding repair equipment, and uses a clamp with adjustable angle and height to install a newly designed powder feeding tube with a powder outlet diameter of 1mm and a lower outer diameter of 3mm or less on the pad in the original coaxial powder feeding device, thereby designing a lateral powder feeding device with adjustable height and angle of the powder feeding tube. The lateral powder feeding device changes the powder delivery direction through the angle-adjustable powder feeding tube, thereby separating the powder outlet path from the light outlet path, and delivering the powder to the surface to be repaired from the side without interfering with the laser light path; secondly, based on the idea of ​​differential transformation of curved surface into plane, the powder outlet diameter of the powder feeding tube of the lateral powder feeding device is designed to be 1mm, so that the powder can evenly cover the cladding surface, ensuring the flatness of the cladding surface, and overcoming the problem of poor powder beam uniformity in the non-vertical powder feeding process of the lateral powder feeding device; thirdly, by optimizing the laser cladding process parameters, the adaptability of the cladding powder to the substrate is improved, the deformation of the inner ring is controlled, and the performance indicators of the inner hole of the repaired vortex flow device are guaranteed. Finally, the cladding layer obtained by the method of the present invention has good quality, is free of cracks and deformation, and meets the process requirements of the flame tube vortex flowmeter. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a morphology picture of the inner ring of the flame tube vortexer of Example 1 before repair;

[0037] Figure 2 This is a morphology diagram of the inner ring of the flame tube vortexer of Example 1 after repair without reaming;

[0038] Figure 3 This is the metallographic structure morphology of the cladding layer after the inner ring of the flame tube vortexer of Example 1 was repaired;

[0039] Figure 4 This is a fluorescent coloring display of the repaired area of ​​the inner ring of the flame tube vortexer of Example 1;

[0040] Figure 5 This is a physical photo of the main part of the original coaxial powder feeding device in the laser cladding repair equipment.

[0041] Figure 6 For the present invention Figure 5 The actual photo of the main part of the lateral powder feeding device obtained after improvement based on the original coaxial powder feeding device is shown.

[0042] Reference numerals:

[0043] 1- powder delivery pipe; 2- angle adjustment mechanism; 3- pad; 4- lens; 5- protective gas path; 6- powder path; 7- cooling water path; 8- height adjustment mechanism; 9- high temperature tape; 10- restraint gas path. DETAILED DESCRIPTION

[0044] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0045] A laser cladding repair method for an aircraft engine flame tube vortex flow device inner ring damage comprises the following steps:

[0046] Step 1: Grind and clean the surface to be repaired;

[0047] Manually polish the inner hole surface of the inner ring of the flame tube vortexer, remove the surface ablation layer, and then perform ultrasonic cleaning;

[0048] Step 2: Adjust and debug the powder feeding device;

[0049] Step 2.1: Improve the original conventional coaxial powder feeding device in the laser cladding repair equipment into a lateral powder feeding device;

[0050] Figure 5The figure shows a physical photo of the original conventional coaxial powder feeding device in the laser cladding repair equipment. As shown in the figure, it includes a powder feeding pipe 1, a cushion block 3, a lens 4, a protective gas path 5, a powder path 6, a cooling water path 7, a constraint gas path 10 and a powder barrel (not shown in the figure); the powder feeding pipe 1 is connected to the powder barrel through the powder path 6, and the powder used for repair in the powder barrel is transported to the powder feeding pipe 1 through the powder path 6; the cushion block 3 is used to adjust the defocus amount; the powder feeding pipe 1 is fixedly connected to the cushion block 3 and installed below the cushion block 3, and the powder outlet of the powder feeding pipe 1 is aligned with the light output path of the laser in the laser cladding repair equipment axis; the lens 4 is used to protect the optical path system; the protective air pipe 5 located at the lens 4 is used to output protective gas to form an air film, and together with the lens 4, prevents the rebounding powder from affecting the optical path system, thereby protecting the optical path system; the powder feeding pipe 1 is annular powder feeding, and the constraint air pipe 5 arranged on the side wall of the powder feeding pipe 1 is used to constrain the powder into an inverted cone; since the size of the powder feeding pipe 1 is large and the heat dissipation is poor, a cooling water pipe 7 is connected to its side wall; in addition, the upper part of the powder feeding pipe 1 is wrapped with high-temperature tape to prevent metal powder from entering the thread of the upper side wall of the powder feeding pipe 1.

[0051] In order to separate the powder outlet path from the light outlet path, the present invention Figure 5 Based on the coaxial powder feeding device shown in the figure, the following structural improvements are made to it:

[0052] First, the powder feeding pipe 1 in the original coaxial powder feeding device is removed;

[0053] Then, according to the idea of ​​surface differential transformation, the powder delivery tube was redesigned and manufactured: if the diameter of the powder outlet hole of the powder delivery tube 1 is too large, it will affect the repair area; if the diameter of the powder outlet hole is too small, the cladding layer height will be insufficient. After many tests, the diameter of the powder outlet hole of the powder delivery tube 1 was finally determined to be 1mm to ensure that the powder used for repair can be evenly fed to the cladding area; Figure 6 As shown, the outer diameter of the middle and upper part of the powder delivery pipe 1 is larger for easy clamping; because the lower part of the powder delivery pipe 1 needs to be partially inserted into the inner ring of the vortex device during repair to ensure that the powder is delivered to the surface to be repaired, the outer diameter of the lower part of the powder delivery pipe 1 is smaller (3 mm or less is recommended) to facilitate insertion into the inner ring of the vortex device; in order to facilitate connection with the powder barrel, a hose is directly used as the powder path 6 after improvement, and the improved powder delivery pipe 1 is connected to the powder barrel through the hose, and the original powder path 6 can be removed (of course, the new powder delivery pipe 1 can also be connected to the powder barrel using the original powder path 6).

[0054] Next, the present invention designs and manufactures a clamp for clamping the powder feeding tube 1, which consists of an angle adjustment mechanism 2 and a height adjustment mechanism 8. The powder feeding tube 1 is installed on the angle adjustment mechanism 2 and is fixed by a top screw. The angle adjustment mechanism 2 is installed on the height adjustment mechanism 8. The angle adjustment mechanism 8 is installed on the pad 3 in the original coaxial powder feeding device.

[0055] At the same time, since the powder outlet hole size of the improved new powder feeding pipe 1 is smaller, the powder outlet amount is also small, and cooling is not required, so the cooling water circuit 7 in the original coaxial powder feeding device is omitted; in addition, the constraining gas circuit 10 is not required to constrain the powder, so the constraining gas circuit 10 is omitted. The remaining components and structures in the original coaxial powder feeding device remain unchanged.

[0056] At this point, a lateral powder feeding device is obtained.

[0057] Step 2.2 Adjust the height and angle of the powder feeding pipe in the lateral powder feeding device according to the damage position;

[0058] First, the defocus amount is ensured. In this case, the laser irradiation point during laser cladding repair is determined by the coaxial red light emitted by the laser in the laser cladding repair equipment, and then the height of the powder feeding tube 1 is adjusted by the height adjustment mechanism 8 in the lateral powder feeding device to ensure that the laser light path is not blocked. Finally, the angle of the powder feeding tube 1 is adjusted by the angle adjustment mechanism 2 in the lateral powder feeding device to ensure that the powder used for repair can be delivered to the laser irradiation point through the appropriate powder feeding gas volume during repair. Finally, it is ensured that when the laser emits light normally, the powder used for repair can be delivered to the surface to be repaired through the powder feeding tube of the lateral powder feeding device.

[0059] Step 3: Formulate laser cladding repair process and select laser cladding repair process parameters;

[0060] According to the damage of the inner ring of the flame tube vortexer, determine the repair area, determine the number of layers and passes to be overlapped during cladding according to the repair area, determine the starting and ending points of cladding, and plan the scanning path; reasonably adjust the process parameters to ensure that the inner ring of the flame tube vortexer does not deform under high-energy environment; the adjusted process parameters are: laser power: 200-500w; scanning speed: 150-300mm / min; spot diameter: 1mm; powder feeding rate: 0.6-1.0r / min; pulse mode: pulse width 15-18; frequency 20-25; duty cycle 40-45%; defocus: 2-6mm;

[0061] Step 4: Laser cladding repair;

[0062] A nickel-chromium alloy powder with a particle size between 100 and 200 μm (preferably 110 to 130 μm, preferably more uniform powder particle size and better cladding quality) is used as the powder for repair. Before cladding, the nickel-chromium alloy powder is placed in a vacuum drying oven and dried at 90 to 130° C. for 1 to 4 hours to ensure that the powder is dry. A fiber laser is used, and according to the laser cladding repair process formulated in step 3, a lateral powder feeding device is used to perform laser cladding repair on the inner ring surface of the flame tube vortexer to be repaired by lateral coaxial powder feeding, so that the thickness of the cladding layer is higher than the substrate surface of the area to be repaired, and during the cladding process of the same layer, the distance between the laser beam focus and the cladding base surface is kept fixed, and the fixed height is 4 mm (defocus amount).

[0063] Step 5: Ream the hole;

[0064] According to the flame tube vortexer design drawings and relevant technical requirements (all known contents, which are available after the flame tube vortexer is designed), the flame tube vortexer is fixed on a vertical drilling machine, and the surface of the cladding layer of the inner ring of the flame tube vortexer repaired by laser cladding is re-reamed by using the vertical drilling machine to ensure that the cladding surface is uniform with the substrate surface;

[0065] Step 6: Repair quality inspection;

[0066] Step 6.1 metallographic analysis and testing;

[0067] Perform metallographic analysis on the repaired cladding layer on the inner ring of the flame tube vortexer. After inspection, if the cladding layer has no cracks, unfused, or pore defects, proceed to step 6.2; if the cladding layer has cracks, unfused, or pore defects, re-grind the cladding layer and return to the above step 3 until it is confirmed that the cladding layer in the repaired area of ​​the flame tube vortexer inner hole has no cracks, unfused, or pore defects, and then proceed to step 6.2;

[0068] Step 6.2: Fluorescent flaw detection;

[0069] Perform fluorescent flaw detection on the inner ring wall of the repaired flame tube vortex flower to determine whether there are cracks or pore defects; if there are defects, re-grind the cladding layer and return to the above step 3 until it is confirmed that the fluorescent flaw detection results of the repaired area of ​​the flame tube vortex flower inner hole show no cracks or pore defects, and then proceed to step 6.3;

[0070] Step 6.3: Dimensional inspection;

[0071] The size of the inner ring of the flame tube vortexer after repair is inspected. If there is no deformation or deviation, the repaired part is qualified; if there is deformation and deviation, but it does not exceed the size requirement, the part is qualified after repair; if there is deformation and deviation and it exceeds the size requirement, the part can only be scrapped. After a large number of actual verifications, the size inspection pass rate has reached more than 70%. Compared with the previous situation where it was impossible to repair and all damaged parts had to be scrapped, the cost of products that cannot be repaired due to scrapping has been greatly reduced.

[0072] Example 1

[0073] The laser cladding repair method for the damaged inner ring of the aircraft engine flame tube vortexer provided in this embodiment comprises the following steps:

[0074] Step 1: Grind and clean the surface to be repaired;

[0075] The inner hole surface of the inner ring of the flame tube vortexer is manually polished, and the surface ablation layer is removed and then ultrasonically cleaned;

[0076] Step 2: Adjust and debug the powder feeding device;

[0077] Step 3: Formulate laser cladding repair process and select laser cladding repair process parameters;

[0078] Formulate laser cladding repair process, determine the repair area, determine the number of layers and passes to be overlapped during cladding according to the repair area, determine the starting and ending points of cladding, and plan the scanning path; select laser cladding repair process parameters as follows: laser power: 250w; scanning speed: 200mm / min; spot diameter: 1mm; powder feeding rate: 0.6r / min; pulse mode: pulse width 15; frequency 20; duty cycle 42%; defocus: 4mm;

[0079] Step 4: Laser cladding repair;

[0080] Nickel-chromium alloy powder with a particle size of 110-115 μm was used as the powder feeding repair material. Before cladding, the nickel-chromium alloy powder was placed in a vacuum drying oven and dried at 110°C for 2 hours. A fiber laser was used to perform laser cladding repair on the sample surface through lateral coaxial powder feeding according to the established laser cladding process, so that the thickness of the cladding layer was higher than that of the substrate surface.

[0081] Step 5: Ream the hole;

[0082] According to the flame tube vortexer drawing and relevant technical requirements, the flame tube vortexer is fixed on a vertical drilling machine, and the surface of the inner ring cladding layer after laser cladding repair is re-reamed using the vertical drilling machine to ensure that the cladding surface is uniform and consistent with the substrate surface;

[0083] Step 6: Repair quality inspection;

[0084] Step 6.1 Perform metallographic analysis on the repaired flame tube vortex inner ring cladding layer. The metallographic structure of the repaired cladding layer is shown in the figure below: Figure 3 As shown, after inspection, the metallographic structure of the cladding layer has no defects such as cracks and unfused;

[0085] Step 6.2 Perform fluorescent flaw detection on the inner wall of the repaired flame tube vortexer. The repaired area is displayed in fluorescent coloring as shown in the figure below. Figure 4 As shown, there are no defects such as cracks and pores after inspection;

[0086] Step 6.3: Check the size of the inner ring of the repaired flame tube vortex finder. There is no deviation or deformation and it meets the size requirements of the repair process.

[0087] Example 2

[0088] The laser cladding repair method for the damaged inner ring of the aircraft engine flame tube vortexer provided in this embodiment comprises the following steps:

[0089] Step 1: Grind and clean the surface to be repaired;

[0090] The inner hole surface of the inner ring of the flame tube vortexer is manually polished, and the surface ablation layer is removed and then ultrasonically cleaned;

[0091] Step 2: Adjust and debug the powder feeding device;

[0092] Step 3: Formulate laser cladding repair process and select laser cladding repair process parameters;

[0093] Formulate laser cladding repair process, determine the repair area, determine the number of layers and passes to be overlapped during cladding according to the repair area, determine the starting and ending points of cladding, and plan the scanning path; select laser cladding repair process parameters as follows: laser power: 300w; scanning speed: 200mm / min; spot diameter: 1mm; powder feeding rate: 1r / min; pulse mode: pulse width 18; frequency 24; duty cycle 45%; defocus: 4mm;

[0094] Step 4: Laser cladding repair;

[0095] Nickel-chromium alloy powder with a particle size of 110-115 μm was used as the powder feeding repair material. Before cladding, the nickel-chromium alloy powder was placed in a vacuum drying oven and dried at 110°C for 2 hours. A fiber laser was used to perform laser cladding repair on the sample surface through lateral coaxial powder feeding according to the established laser cladding process, so that the thickness of the cladding layer was higher than that of the substrate surface.

[0096] Step 5: Ream the hole;

[0097] According to the flame tube vortexer drawing and relevant technical requirements, the flame tube vortexer is fixed on a vertical drilling machine, and the surface of the inner ring cladding layer after laser cladding repair is re-reamed using the vertical drilling machine to ensure that the cladding surface is uniform and consistent with the substrate surface;

[0098] Step 6: Repair quality inspection;

[0099] Step 6.1 Perform metallographic analysis on the repaired flame tube vortexer inner ring cladding layer structure, and after inspection, the cladding layer metallographic structure has no defects such as cracks and unfused;

[0100] Step 6.2: Perform fluorescent flaw detection on the inner ring wall of the repaired flame tube vortexer, and no defects such as cracks are found after inspection;

[0101] Step 6.3: Check the size of the inner ring of the repaired flame tube vortex finder. There is no deviation or deformation and it meets the size requirements of the repair process.

Claims

1. A laser cladding repair method for damaged inner ring of vortex flow tube of aircraft engine, characterized in that: The following steps are involved: Step 1: Grind and clean the surface to be repaired; Step 2: Improve the coaxial powder feeding device in the laser cladding repair equipment to a lateral powder feeding device with adjustable height and angle of the powder feeding tube, and the diameter of the powder outlet hole of the improved powder feeding tube is 1 mm, and then adjust the height and angle of the powder feeding tube in the lateral powder feeding device; Step 3: Formulate laser cladding repair process and select laser cladding repair process parameters; process parameters are selected from the following parameter range: laser power: 200-500w; scanning speed: 150-300mm / min; spot diameter: 1mm; powder feeding rate: 0.6-1.0r / min; pulse mode: pulse width 15-18; frequency 20-25; duty cycle 40-45%; defocus: 2-6mm; Step 4: using a dried nickel-chromium alloy powder with a particle size of 100-200 μm as a powder for repair, using a fiber laser, according to the laser cladding repair process and process parameters formulated in step 3, and using the lateral powder feeding device to perform laser cladding repair on the inner ring of the flame tube vortexer to be repaired by lateral powder feeding; Step 5: Re-reaming the surface of the cladding layer of the inner ring of the flame tube vortexer repaired by laser cladding; Step 6: Repair quality inspection; Step 6.1: metallographic analysis is performed on the cladding layer on the inner ring of the flame tube vortexer after repair. If the cladding layer has no cracks, no fusion, or pore defects, the process proceeds to step 6.

2. If the cladding layer has cracks, no fusion, or pore defects, the cladding layer is re-polished and the process returns to step 3 above until it is confirmed that the cladding layer in the repaired area of ​​the flame tube vortexer inner hole has no cracks, no fusion, or pore defects, and then the process proceeds to step 6.

2. Step 6.2 Fluorescent flaw detection inspection; Perform fluorescent flaw detection on the inner ring wall of the repaired flame tube vortex flower to determine whether there are cracks or pore defects; if there are defects, re-grind the cladding layer and return to the above step 3 until it is confirmed that the fluorescent flaw detection results of the repaired area of ​​the flame tube vortex flower inner hole show no cracks or pore defects, and then proceed to step 6.3; Step 6.3 Dimensional inspection; The dimensions of the inner ring of the repaired flame tube vortexer are inspected. If there is no deformation or deviation, the part is qualified for repair; if there is deformation and deviation, but it does not exceed the size requirement, the part is qualified for repair; if there is deformation and deviation and it exceeds the size requirement, the part can only be scrapped.

2. The laser cladding repair method for the damaged inner ring of the aircraft engine flame liner vortexer according to claim 1 is characterized in that: The lateral powder feeding device described in step 2 is improved on the basis of the structure of the original coaxial powder feeding device by the following method: First, remove the powder feeding pipe in the original coaxial powder feeding device; Then, the powder delivery pipe is redesigned and manufactured. The diameter of the powder outlet of the new powder delivery pipe is 1mm. The upper outer diameter is large for easy clamping, and the lower outer diameter is less than or equal to 3mm to extend into the inner ring of the vortex flow device to ensure that the powder is delivered to the surface to be repaired. Next, a fixture for clamping a new powder delivery pipe is designed and manufactured. The angle is composed of an angle adjustment mechanism and a height adjustment mechanism. The new powder delivery pipe is installed on the angle adjustment mechanism, which is installed on the height adjustment mechanism. The height adjustment mechanism is installed on the pad in the original coaxial powder delivery device. At the same time, the cooling water circuit and the restraining gas circuit in the original coaxial powder feeding device are omitted, and the structure and connection relationship of the other components in the original coaxial powder feeding device remain unchanged; Finally, a new powder delivery pipe is installed on the cushion block through a clamp, and the upper end of the new powder delivery pipe is connected to the powder barrel through a powder path; At this point, the lateral powder feeding device is obtained.

3. The laser cladding repair method for the damaged inner ring of the aircraft engine flame liner vortexer according to claim 2 is characterized in that: The method for formulating the laser cladding repair process in step 3 is specifically as follows: determine the repair area according to the damage condition of the inner ring of the flame tube vortexer, determine the number of layers and passes required for cladding according to the repair area, determine the starting and ending points of the cladding, and plan the scanning path.

4. The laser cladding repair method for the damaged inner ring of the aircraft engine flame liner vortexer according to claim 3 is characterized in that: In step 4, nickel-chromium alloy powder with a particle size of 110-130 μm is used as the powder for repair. Before cladding, the nickel-chromium alloy powder is placed in a vacuum drying oven at 90-130° C. and dried for 1-4 hours to ensure that the powder is dry.

5. The laser cladding repair method for the damaged inner ring of the aircraft engine flame liner vortexer according to claim 4 is characterized in that: Step 4: When performing laser cladding repair, the thickness of the cladding layer is higher than the substrate surface of the area to be repaired, and during the cladding process of the same layer, the distance between the laser beam focus and the cladding base surface is kept fixed at a fixed height of 4 mm.

6. The laser cladding repair method for the damaged inner ring of the aircraft engine flame liner vortexer according to claim 5 is characterized in that: In step 5, the flame tube vortexer is fixed on a vertical drilling machine according to the flame tube vortexer design drawing and relevant technical requirements, and the surface of the cladding layer of the inner ring of the flame tube vortexer repaired by laser cladding is re-reamed using the vertical drilling machine.

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