Machining method for flame tube assembly of aero-engine

Abstract

The invention discloses an aero-engine flame tube assembly machining method, which belongs to the technical field of aero-engine machining, and comprises the following steps: machining a film hole in a circular ring at the head of a flame tube assembly and a film hole in a bevel edge; welding a head circular ring and an inner wall of the flame tube assembly; converting the axial reference and the central reference of the part; converting the angular reference of the blank piece to the angular reference of the machined piece; with the angular holes in the mounting edges as the reference, the laces of the mounting edges are machined, and the mounting edges are machined through the linear cutting technology to form the laces; a ring groove air film hole is machined through high-speed electric spark, a second supporting face is supported through a second supporting clamp, and the air film hole in the ring groove is machined; the inner wall is subjected to spraying treatment; and performing laser processing on the inner wall mixing holes. The method has the advantage that the risks of deformation and size out-of-tolerance of the flame tube assembly in the machining process are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of aviation engine processing, in particular to a method for processing an aviation engine flame tube component. Background Art

[0002] The flame tube assembly is an important part of the combustion chamber of an aircraft engine. Its main function is to organize combustion and maintain a stable fire source. It has thin wall thickness and complex surface. It is formed by welding several flame tubes together. It needs to go through welding process and subsequent machining to ensure the size. The processing of such parts has the following difficulties: 1. Due to the large deformation after electron beam welding, the conversion error between the axial processing datum of the part, there will be a large deviation during the processing of the head boss of the part, and the parallelism is out of tolerance; 2. The deformation of the supporting surface of the part is large, which will cause the deformation of the datum surface and the length out of tolerance during the machining process; 3. The rigidity of the part is poor, which will cause vibration marks during the machining process; 4. After welding aging, each installation edge of the part will have a deformation of about 0.5 to 0.6 mm, which increases the difficulty of part processing and is not easy to ensure the processing quality of the part; 5. There are many air film holes, and the parts are greatly deformed after processing.

[0003] Figure 1 The cross-sectional structure diagram of a flame tube assembly for an aircraft engine is shown in the figure. The flame tube inner ring part 100 is an annular part with a wall thickness of 1.5 mm. Its cross-sectional structure includes a front mounting edge 1, a head plane and a boss 2, a weld 3, an inner wall 4, and an annular groove 5. There are multiple air film holes on the head plane and the boss 2 and the inner wall 4 (not shown in the figure). The size requirements of the flame tube inner ring part 100 include parallelism of 0.05 and verticality of 0.05. That is to say, the size precision requirements of the flame tube inner ring part 100 are high. Since the wall of the part is thin, the processing process requires welding and heat treatment processes, and the number of air film holes is large and the removal margin is large, the reference surface of the part is easy to deform, resulting in a series of dimensions related to the reference surface often exceeding the tolerance. The existing processing process is overly dependent on the operating level of skilled personnel and the on-site processing environment, has great limitations, and it is difficult to essentially control the deformation and processing deviation of the part. Summary of the invention

[0004] The invention provides a method for machining an aircraft engine flame tube assembly, so as to solve the technical problems that the flame tube assembly is prone to deformation and dimensional deviation during machining.

[0005] According to one aspect of the present invention, a method for machining an aircraft engine flame tube assembly is provided, comprising the following steps:

[0006] S100, processing the air film holes on the head ring and the air film holes on the bevel of the flame tube assembly;

[0007] S200, welding the head ring and inner wall of the flame tube assembly;

[0008] S300, the boss surface is processed to form the first support surface, the mounting edge is processed to form the second support surface, and the axial reference and center reference of the parts are converted to avoid deformation of the mounting edges and inner holes before and after welding.

[0009] The impact of part finishing;

[0010] S400, converting the angular reference of the blank and milling the boss, machining the angular hole on the mounting edge, and realizing the conversion from the angular reference of the blank to the angular reference of the machined part;

[0011] S500, based on the angle hole on the installation edge, processes the lace of the installation edge, and uses wire cutting technology to

[0012] Manual edge forming lace;

[0013] S600, high-speed EDM machining of annular groove air film holes, using the second support fixture to support the second support surface,

[0014] The air film holes on the annular groove are processed to ensure the ventilation and heat dissipation function of the annular groove.

[0015] S700, spray treatment on the inner wall: spray thermal barrier coating on the inner wall surface, perform plasma spraying, material

[0016] It is aluminum silicon coating;

[0017] S800, laser processing of inner wall mixing holes: use the third support fixture, set the angle pin for the diagonal hole, support the second support surface, find the center reference outer circle, and process different sizes of mixing holes on the inner wall coating.

[0018] mixed hole;

[0019] S900, laser processing of inner wall cooling holes: using the second support fixture, setting angle pins for the diagonal holes, supporting the installation edge to align the outer circle of the installation edge, processing cooling holes of different sizes on the inner wall coating, and the cooling holes and mixing holes are staggered.

[0020] Optionally, in step S100, when processing the air film hole, the processing method is adjusted according to the position of the air film hole to avoid the influence of deformation caused by stress change of the part after the part material is removed on the reference.

[0021] Optionally, step S100 of processing the air film holes on the circular ring of the flame tube assembly head and the air film holes on the bevel includes the following steps:

[0022] S110, laser processing of air film holes on the head plane: align any large hole on the head plane as the angular position, and process the air film holes around the large hole to reduce the influence of deformation caused by stress changes after part material removal on the benchmark.

[0023] S120, EDM machining of air film holes on the head bevel: align any large hole on the head plane as the angular position and machine the air film holes on the head bevel.

[0024] Optionally, in step S120, the air film hole to be processed is close to the installation edge, and the outlet is a load-bearing arc portion, and electric spark machining is used to reduce deformation of the parts.

[0025] Optionally, step S300 includes the following steps:

[0026] S310, determine the axial reference of the part: color the inner wall end face, support and press the coloring point, process the boss surface, and process the first support surface. The inner wall end face is the axial reference before welding, and the first support surface is the axial reference after welding, so as to realize the conversion from the axial reference before welding to the axial reference after welding, avoiding welding.

[0027] The influence of deformation of front and rear end faces on part processing;

[0028] S320, convert the axial datum and turn the annular groove: use the first supporting fixture to color support the first supporting surface, pass the screw through the circular hole of the head to clamp the part, align the inner hole circle of the inner wall, process the mounting edge and the annular groove, and process the second supporting surface and center datum. The second supporting surface is the designed axial datum, thereby realizing the conversion from the axial datum in processing to the designed axial datum.

[0029] Optionally, step S400 includes the following steps:

[0030] Use the second supporting fixture to support the second supporting surface, align the outer circle of the installation edge, and align the evenly distributed bosses at the bosses to roughly determine the angle;

[0031] After setting the workpiece coordinate system, pre-program the milling cutter to perform milling with a depth of 0.3mm on several evenly distributed boss circular holes on the head, and then check one by one whether the pre-milled center hole of each boss is in the exact center of the boss. If there is a deviation, adjust the workpiece coordinate system and repeat the above steps until the pre-milled center hole of each boss is in the exact center of the boss;

[0032] Angular holes are processed on the installation edge, and the boss surface is milled. Several evenly distributed bosses on the blank serve as the angular reference of the blank, and the angular holes on the installation edge serve as the angular reference of the machined part, thereby realizing the conversion from the angular reference of the blank to the angular reference of the machined part.

[0033] Optionally, in step S600, when the second supporting surface is supported by the second supporting fixture, angle pins are provided on the second supporting fixture corresponding to the angle holes to align the outer circle of the mounting edge.

[0034] Optionally, before step S700, the step of polishing the parts is also included to remove burrs and flash generated by machining, so as to avoid excess materials in the air film holes and the annular grooves.

[0035] Optionally, before step S700, a fluorescent inspection step is also included to perform a fluorescent inspection on the installation edge and the air film hole to eliminate crack defects.

[0036] Optionally, after step S900, the following steps are further included:

[0037] Remove splash and burrs from air film holes: Remove splash and burrs from air film holes by flushing the cooling holes with water as the medium and applying pressure. Perform a light-transmitting inspection on all holes to remove any excess material that may be present in the holes.

[0038] In summary, the present application includes at least one of the following beneficial technical effects:

[0039] 1. By converting the axial reference and center reference before and after welding, the parts can avoid deformation caused by stress concentration during welding, ensuring that the accuracy of each mounting edge and inner hole remains stable during fine machining;

[0040] 2. By using special fixtures to support parts and using screws to punch and press during processing, the rigidity of parts during processing is significantly enhanced, preventing tool marks and dimensional deviations caused by unstable clamping or vibration, and ensuring the accuracy and surface quality of key parts;

[0041] 3. By pre-milling and checking the center position of the boss when converting the angular reference of the blank, the angular reference of the blank and the angular reference of the machined part are accurately converted, avoiding insufficient machining allowance or machining error, and ensuring the accuracy requirements of subsequent angular holes and mounting edges.

[0042] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0044] Figure 1 It is a schematic diagram of a first supporting fixture of the method for processing the flame tube assembly of an aircraft engine of the present invention;

[0045] Figure 2 It is a schematic diagram of a second supporting fixture of the method for processing the flame tube assembly of an aircraft engine of the present invention;

[0046] Figure 3 It is a schematic diagram of the third supporting fixture of the method for processing the aircraft engine flame tube assembly of the present invention.

[0047] Legend:

[0048] 1. The first support is the clamp; 2. The second support is the clamp; 3. The third support is the clamp. DETAILED DESCRIPTION

[0049] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0050] The following is combined with Figure 1-3 This application is described in further detail.

[0051] The present application embodiment discloses a method for processing an aircraft engine flame tube assembly, comprising the following steps:

[0052] A method for processing an aircraft engine flame tube assembly is provided, comprising the following steps:

[0053] S100, processing the air film holes on the head ring and the air film holes on the bevel of the flame tube assembly;

[0054] S200, welding the head ring and inner wall of the flame tube assembly;

[0055] S300, the boss surface is processed to form the first support surface, the mounting edge is processed to form the second support surface, and the axial reference and center reference of the parts are converted to avoid deformation of the mounting edges and inner holes before and after welding.

[0056] The impact of part finishing;

[0057] S400, converting the angular reference of the blank and milling the boss, machining the angular hole on the mounting edge, and realizing the conversion from the angular reference of the blank to the angular reference of the machined part;

[0058] S500, based on the angle hole on the installation edge, processes the lace of the installation edge, and uses wire cutting technology to

[0059] Manual edge forming lace;

[0060] S600, high-speed EDM machining of annular groove air film holes, using the second support fixture to support the second support surface,

[0061] The air film holes on the annular groove are processed to ensure the ventilation and heat dissipation function of the annular groove.

[0062] S700, spray treatment on the inner wall: spray thermal barrier coating on the inner wall surface, perform plasma spraying, material

[0063] It is aluminum silicon coating;

[0064] S800, laser processing of inner wall mixing holes: use the third support fixture, set the angle pin for the diagonal hole, support the second support surface, find the center reference outer circle, and process different sizes of mixing holes on the inner wall coating.

[0065] mixed hole;

[0066] S900, laser processing of inner wall cooling holes: using the second support fixture, setting angle pins for the diagonal holes, supporting the installation edge to align the outer circle of the installation edge, processing cooling holes of different sizes on the inner wall coating, and the cooling holes and mixing holes are staggered.

[0067] In step S100, when processing the air film hole, the processing method is adjusted according to the position of the air film hole to avoid the influence of deformation caused by the stress change of the part after the part material is removed on the reference.

[0068] The processing method will affect the heat input and cooling process of the part material. Laser processing is a local heat source processing with a small heat-affected zone and can accurately remove materials, but the heat generated locally may cause thermal expansion and stress concentration of the material. Especially for hole processing in large areas or flat parts, the thermal effect of laser processing is small and controllable, which is suitable for such processing; EDM is a type of discharge processing that does not directly act on the surface of the material to remove it by grinding, but ablates the material through local discharge. The heat-affected zone generated by EDM is relatively smaller, so it is more suitable for use in parts close to the mounting edge or complex shapes. Especially when the part has a complex shape or thin wall, this processing method can reduce the local stress concentration caused by heat accumulation and avoid deformation caused by thermal expansion. Adjusting the processing method can avoid excessive thermal stress during material removal and maintain the stability of the part shape by selecting a suitable processing heat source.

[0069] Specifically, step S100 includes the following steps of processing the air film holes on the circular ring of the flame tube assembly head and the air film holes on the bevel:

[0070] S110, laser processing of air film holes on the head plane: align any large hole on the head plane as the angular position, and process the air film holes around the large hole to reduce the influence of deformation caused by stress changes after part material removal on the benchmark;

[0071] S120, EDM machining of air film holes on the head bevel: align any large hole on the head plane as the angular position and machine the air film holes on the head bevel.

[0072] In step S110, first, a larger hole on the head plane is accurately positioned and aligned by measuring equipment, and it is used as an angular reference. The role of the angular reference is to ensure that the processing positions of all air film holes during the processing are determined relative to the center of this large hole. Once the angular position of the large hole is determined, the processing positions of other air film holes around the large hole will also be accurately positioned based on this reference. This can ensure the consistency of the position accuracy of each air film hole in the relative angular direction; laser technology is used to process the air film holes around the large hole. Laser processing is a high-precision, low-heat-impact processing method suitable for thin-walled structural parts. The laser beam will focus the melted material through high energy to form holes. During laser processing, the amount of material removal can be accurately controlled by adjusting the focal length, power and other parameters of the laser, thereby avoiding excessive heat input and reducing the impact of local thermal stress concentration on the material. By gradually processing the air film holes around the large hole, it can be ensured that the material is uniformly stressed during the processing and the deformation of the parts caused by excessive release of local stress can be avoided.

[0073] In step S120, first align a larger hole on the head plane as an angular reference. Through the position of this large hole, it can be ensured that the air film holes on the inclined surface maintain an accurate relative position in the angular direction. After aligning the large hole as the processing reference, it is ensured that during the entire processing process, the position of the air film holes on the inclined surface of the head relative to the large hole will not deviate, thereby ensuring the processing accuracy of the air film holes.

[0074] The air film hole to be processed is close to the mounting edge, and the outlet is a load-bearing arc part. Electrospark machining is used to reduce the deformation of the part. The area close to the mounting edge is usually less rigid, and the part is prone to deformation in this area. Using electrospark machining, this non-contact machining method can effectively avoid mechanical impact on thin-walled or weakly rigid parts during machining, thereby reducing the possibility of deformation in this area.

[0075] In step S200, strict alignment and fixation are required before welding to ensure the accurate positioning of the head ring and the inner wall. Through a fixture or support device, the two parts are ensured to remain stable during the welding process to avoid position offset during welding affecting the accuracy. Through electron beam welding, a focused electron beam is used to melt the joint area of ​​the head ring and the inner wall to form a precise weld. This process can achieve high-strength welding on thin-walled parts while maintaining the shape stability of the parts.

[0076] Step S300 includes the following steps:

[0077] S310, determining the axial reference of the part: coloring the inner wall end face, supporting and pressing the coloring point, processing the boss surface, processing the first supporting surface, the inner wall end face is the axial reference before welding, and the first supporting surface is the axial reference after welding, so as to realize the conversion from the axial reference before welding to the axial reference after welding, and avoid the influence of the deformation of each end face before and after welding on the part processing;

[0078] The welding process may cause thermal deformation of the parts, resulting in the loss of accuracy of the reference surface selected before welding. By re-processing a new axial reference (the first support surface) after welding, the influence of welding deformation on subsequent finishing can be effectively avoided, ensuring the size and accuracy requirements of the final product; through reference conversion, it is ensured that the parts always have an accurate and reliable reference surface at different processing stages, especially after welding, the new reference surface can ensure the processing accuracy of each part, avoid the accumulation of dimensional errors, and thus improve the overall processing quality and stability of the parts; the conversion of the axial reference provides a new positioning reference for subsequent processes. This new reference surface can ensure the dimensional accuracy of the parts in subsequent processing such as turning and milling, especially when processing important parts such as mounting edges and annular grooves, ensuring the accuracy transfer and interchangeability of parts in the entire processing chain.

[0079] S320, converting the axial reference and turning the annular groove: Use the first support fixture to color support the first support surface, pass the screw through the head circular hole to press the part, align the inner wall inner hole circle, process the installation edge and the annular groove, and process the second support surface and center reference. The second support surface is the design axial reference, so as to realize the conversion from the axial reference in processing to the axial reference in design. By converting the axial reference, from the temporary reference (first support surface) in welding and processing to the reference required by the final design (second support surface), it is ensured that the processing of the part is always based on an accurate and stable reference surface. Especially in the processing of annular grooves and mounting edges, this conversion helps to improve the concentricity, parallelism and surface quality of parts; the conversion of the datum surface ensures the accurate transfer of the axial datum from the processing process, avoiding the deformation of the parts during welding and preliminary processing affecting the final size and shape consistency. Especially for thin-walled and complex-shaped parts, the datum conversion can ensure the minimum error during the processing; by accurately processing the mounting edge and annular groove, and ensuring the consistency of the second support surface with the design datum, it can ensure that the parts have high-precision matching requirements during the final assembly. The accuracy of the annular groove and the mounting edge is directly related to the sealing, pressure resistance and working performance of the parts.

[0080] Step S400 includes the following steps:

[0081] Use the second supporting fixture to support the second supporting surface, align the outer circle of the installation edge, and align the evenly distributed bosses at the bosses to roughly determine the angle;

[0082] After setting the workpiece coordinate system, pre-program the milling cutter to perform milling with a depth of 0.3mm on several evenly distributed boss circular holes on the head, and then check one by one whether the pre-milled center hole of each boss is in the exact center of the boss. If there is a deviation, adjust the workpiece coordinate system and repeat the above steps until the pre-milled center hole of each boss is in the exact center of the boss;

[0083] Angular holes are processed on the installation edge, and the boss surface is milled. Several evenly distributed bosses on the blank serve as the angular reference of the blank, and the angular holes on the installation edge serve as the angular reference of the machined part, thereby realizing the conversion from the angular reference of the blank to the angular reference of the machined part.

[0084] The main function of step S400 is to ensure that the angular accuracy of the part can be effectively controlled during the process from the blank to the finished part by converting the angular reference of the part. The specific operation includes using the second support fixture to support the second support surface, and preliminarily determining the angular position of the part by aligning the outer circle of the mounting edge and the uniformly distributed boss. After setting the workpiece coordinate system, milling pre-processing is performed to check whether the boss circular hole is located in the exact center position one by one, and eliminate the deviation by adjusting the coordinate system. This process ensures the consistency of the geometric center of each boss with the processing reference, avoiding the accumulation of processing errors. Further angular reference conversion is achieved by processing angular holes on the mounting edge. Through precise positioning and milling, it is ensured that the uniformly distributed boss (blank reference) of the blank is converted to the angular hole (processing reference) of the machined part. The core function of this step is to improve the assembly accuracy of the parts, especially for aircraft engine parts with high installation and assembly requirements, the accuracy of the angular reference is crucial. Through this reference conversion, the angular error can be reduced, ensuring that the parts have good symmetry and accuracy in subsequent assembly, thereby improving the performance and reliability of the entire product.

[0085] In step S600, when the second supporting surface is supported by the second supporting fixture, an angular pin is provided on the second supporting fixture corresponding to the angular hole to align the outer circle of the mounting edge. When the second supporting surface is supported by the second supporting fixture, the outer circle of the mounting edge is aligned by providing an angular pin on the fixture, which is used to ensure that the part can be accurately positioned during the processing, thereby ensuring the processing accuracy of the angular hole and the mounting edge. The provision of the angular pin can make the position of the part in the fixture more stable, and by accurately aligning with the outer circle of the mounting edge, the angular error caused by the position offset of the part during the processing can be avoided. The precise alignment of this process is crucial for high-precision parts such as aircraft engines, especially for parts that need to maintain symmetry and high-precision assembly. Through the auxiliary positioning of the angular pin, it is ensured that each hole position of the part is consistent with the angular reference when the ring groove air film hole is processed on the machine tool, so as to prevent offset or error accumulation after processing. In addition, the combination of the supporting fixture and the angular pin can also effectively prevent the slight offset caused by vibration or stress generated during the processing, thereby ensuring the assembly accuracy, functionality and durability of the final part. This precise positioning system improves machining stability and overall accuracy, helping to ensure the machining quality of demanding parts.

[0086] Before step S700, the step of polishing the parts is also included to remove burrs and flash generated by machining, so as to avoid excess materials in the air film holes and the annular grooves.

[0087] Before step S700, a fluorescent inspection step is also included to perform a fluorescent inspection on the installation edge and the air film hole to eliminate crack defects.

[0088] After step S900, the following steps are also included to remove splashes and burrs from the air film holes: to remove splashes and burrs from the air film holes, water is used as a medium and the cooling holes are flushed after being pressurized, and all holes are inspected through light to remove any unnecessary matter that may exist in the holes.

[0089] A specific implementation of this embodiment includes the following steps:

[0090] Step A, laser processing of air film holes on the head plane: align any large hole on the head plane as the angular position, and process the air film holes around the large hole. A total of 644 air film holes of different sizes are processed to reduce the influence of deformation caused by stress changes after part material removal on the benchmark.

[0091] Step B, EDM head bevel air film hole: Align any large hole on the head plane as the angular position, and process the air film holes on the head bevel, a total of 294 air film holes. Since the air film holes are close to the installation edge and the outlet is a load-bearing arc, EDM is used instead of laser processing to reduce the deformation of the parts caused by the heat generated by the electromachining ablation.

[0092] Step C, welding the head ring and the inner wall: arranging an electron beam welding process, welding the head ring and the inner wall at the weld, and performing stress relief treatment, X-ray inspection and fluorescent inspection after welding to ensure the quality of the weld;

[0093] Step D, determining the axial reference of the part after welding: coloring the inner wall end face, supporting and pressing the colored point, processing the boss surface, and processing the first supporting surface, so as to realize the conversion from the axial reference before welding (i.e., the inner wall end face) to the axial reference after welding (i.e., the boss surface), and avoid the influence of the deformation of each end face before and after welding on the part processing;

[0094] Step E, converting the axial reference and turning the annular groove: providing a first supporting fixture, coloring and supporting the first supporting surface processed in step D, passing a screw through the circular hole of the head to press the part, aligning the inner hole circle of the inner wall, processing the mounting edge and the annular groove, processing the axial reference (i.e., the second supporting surface) and the center reference, so as to realize the conversion from the axial reference in processing (i.e., the boss end face) to the designed axial reference (i.e., the mounting edge);

[0095] Step F, converting the angular reference of the blank and milling the boss: providing a second supporting fixture to support the second supporting surface processed in step E (if conditions permit, the second supporting surface can be colored for support), aligning the outer circle of the mounting edge, and aligning the evenly distributed bosses at the bosses to roughly determine the angular direction, after setting the workpiece coordinate system, pre-compiled a milling cutter processing program to perform 0.3mm depth milling on several evenly distributed boss circular holes on the head, and then check one by one whether the pre-milled center hole of each boss is in the center of the boss (the judgment basis is to ensure the subsequent processing allowance), if there is a deviation, adjust the workpiece coordinate system and repeat the above steps until the pre-milled center hole of each boss is in the center of the boss, finally process several holes and angular holes on the mounting edge, and mill the boss surface, so as to realize the conversion from the angular reference of the blank (i.e., several evenly distributed bosses of the blank) to the angular reference of the machined part (i.e., the angular holes on the mounting edge);

[0096] Step G, cutting the installation edge: providing a third supporting fixture, setting an angle pin on the angle hole processed in step F, aligning the center reference circle, and processing the installation edge using a wire cutting process to ensure the requirements of the part's lace angle and wall thickness;

[0097] Step H, high-speed electrospark machining of annular groove air film holes: provide a second supporting fixture to support the second supporting surface machined in step E, set an angle pin for the angle hole machined in step F, align the outer circle of the mounting edge, and machine the air film holes on the annular groove to ensure the ventilation and heat dissipation function of the annular groove;

[0098] Step I, polishing and repairing the parts: arranging fitter work to remove burrs and flash generated by the above machining process, so as to avoid excess materials in the air film hole and the annular groove;

[0099] Step J, fluorescence inspection: arrange fluorescence inspection content, perform fluorescence inspection on the installation edge and air film hole to eliminate crack defects;

[0100] Step K, spraying the inner wall: Arrange a spraying process, spray the thermal barrier coating on the inner wall surface, perform plasma spraying, and the material is aluminum silicon coating. This can reduce the influence of thermal fatigue, gas oxidation corrosion, wear, etc. on the flame tube and increase the life of the flame tube.

[0101] Step L, laser processing of inner wall mixing holes: provide a third supporting fixture, set angle pins for the angle holes processed in step F, support the second supporting surface processed in step E, locate the center reference outer circle, and process mixing holes of different sizes in the inner wall coating area.

[0102] Step M, laser processing of inner wall cooling holes: provide a second supporting fixture, set angle pins for the angle holes processed in step F, support the installation edge, align the outer circle of the installation edge, and process a total of 12 rows of cooling holes of different sizes on the inner wall coating. The cooling holes and mixing holes are staggered to enhance the cooling effect of the combustion chamber.

[0103] Step N, remove splash and burrs from the air film holes: remove splash and burrs from the air film holes, use water as a medium, pressurize and flush the cooling holes, and perform light inspection on all holes to remove any excess material that may be in the holes.

[0104] The main problems and methods solved by this processing method are as follows:

[0105] 1. Through step A and step B, the air film holes on the head ring and the air film holes on the bevel are processed respectively, and the processing method is adjusted according to the position of the air film holes to avoid the influence of deformation on the datum caused by the stress change of the part after the part material is removed; 2. After welding, steps D and E are arranged to convert the axial datum and the center datum of the part respectively to avoid the influence of the deformation of the mounting edges and the inner holes before and after welding on the finishing of the part; 3. Through the screw perforation and clamping method on the second supporting fixture set in step E, the supporting and clamping parts are increased to enhance the rigidity of the parts and avoid the pressure plate pressing on the arc surface Cause clamping deformation, and ultimately ensure the size and roughness requirements of the installation edge reference and the annular groove; 4. By aligning several evenly distributed bosses of the boss in step F to roughly determine the angular direction, and adjusting the processing according to whether the milling cutter is in the center of the boss after pre-milling, the conversion error between the angular reference of the blank and the angular reference of the machined part is avoided, thereby eliminating the problem of insufficient boss processing allowance; 5. By arranging steps F and G to process the installation edge angular holes and the installation edge lace respectively, the deformation of the installation edge caused by CNC milling is avoided, and the angular position of the angular holes and the lace wall thickness requirements are finally guaranteed.

[0106] Since special fixtures are used to constrain the processing parts in most processing processes, the interchangeability of parts during processing is good, which reduces the dependence on the operating level of skilled personnel. There are also special benchwork deburring and cleaning steps to prevent the phenomenon of excess material adhering to the air film holes. The precision dimensional quality of parts is stable and the qualified rate is high.

[0107] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for processing an aircraft engine flame tube assembly, characterized in that: The steps include: S100, processing the air film holes on the head ring and the air film holes on the bevel of the flame tube assembly; S200, welding the head ring and inner wall of the flame tube assembly; S300, the boss surface is processed to form a first support surface, the mounting edge is processed to form a second support surface, and the axial reference and the center reference of the part are converted to avoid the influence of the deformation of each mounting edge and each inner hole before and after welding on the fine processing of the part; S400, converting the angular reference of the blank and milling the boss, machining the angular hole on the mounting edge, and realizing the conversion from the angular reference of the blank to the angular reference of the machined part; S500, taking the angle hole on the installation edge as a reference, processing the lace of the installation edge, and forming the lace by processing the installation edge by wire cutting technology; S600, high-speed electrospark machining of annular groove air film holes, uses the second support fixture to support the second support surface, and processes the air film holes on the annular groove to ensure the ventilation and heat dissipation function of the annular groove. S700, spraying treatment on the inner wall: spraying thermal barrier coating on the inner wall surface, plasma spraying, the material is aluminum silicon coating; S800, laser processing of inner wall mixing holes: using the third support fixture, setting angle pins for the diagonal holes, supporting the second support surface, so as to find the center reference outer circle part, and process mixing holes of different sizes in the inner wall coating part; S900, laser processing of inner wall cooling holes: using the second support fixture, setting angle pins for the diagonal holes, supporting the installation edge to align the outer circle of the installation edge, processing cooling holes of different sizes on the inner wall coating, and the cooling holes and mixing holes are staggered.

2. The method for processing an aircraft engine flame tube assembly according to claim 1, characterized in that: In step S100, when processing the air film hole, the processing method is adjusted according to the position of the air film hole to avoid the influence of deformation caused by the stress change of the part after the part material is removed on the reference.

3. The method for processing an aircraft engine flame tube assembly according to claim 2, characterized in that: Step S100 includes the following steps: S110, laser processing of air film holes on the head plane: align any large hole on the head plane as the angular position, and process the air film holes around the large hole to reduce the influence of deformation caused by stress changes after part material removal on the benchmark. S120, EDM machining of air film holes on the head bevel: align any large hole on the head plane as the angular position and machine the air film holes on the head bevel.

4. The method for processing an aircraft engine flame tube assembly according to claim 3, characterized in that: In step S120, the air film hole to be processed is close to the installation edge, and the outlet is a load-bearing arc part, and electric spark machining is used to reduce deformation of the parts.

5. The method for processing an aircraft engine flame tube assembly according to claim 4, characterized in that: Step S300 includes the following steps: S310, determining the axial reference of the part: coloring the inner wall end face, supporting and pressing the coloring point, processing the boss surface, processing the first supporting surface, the inner wall end face is the axial reference before welding, and the first supporting surface is the axial reference after welding, so as to realize the conversion from the axial reference before welding to the axial reference after welding, and avoid the influence of the deformation of each end face before and after welding on the part processing; S320, convert the axial datum and turn the annular groove: use the first supporting fixture to color support the first supporting surface, pass the screw through the circular hole of the head to clamp the part, align the inner hole circle of the inner wall, process the mounting edge and the annular groove, and process the second supporting surface and center datum. The second supporting surface is the designed axial datum, thereby realizing the conversion from the axial datum in processing to the designed axial datum.

6. The method for processing an aircraft engine flame tube assembly according to claim 5, characterized in that: Step S400 includes the following steps: Use the second supporting fixture to support the second supporting surface, align the outer circle of the installation edge, and align the evenly distributed bosses at the bosses to roughly determine the angle; After setting the workpiece coordinate system, pre-program the milling cutter to perform milling with a depth of 0.3mm on several evenly distributed boss circular holes on the head, and then check one by one whether the pre-milled center hole of each boss is in the exact center of the boss. If there is a deviation, adjust the workpiece coordinate system and repeat the above steps until the pre-milled center hole of each boss is in the exact center of the boss; Angular holes are processed on the installation edge, and the boss surface is milled. Several evenly distributed bosses on the blank serve as the angular reference of the blank, and the angular holes on the installation edge serve as the angular reference of the machined part, thereby realizing the conversion from the angular reference of the blank to the angular reference of the machined part.

7. The method for processing an aircraft engine flame tube assembly according to claim 6, characterized in that: In step S600, when the second supporting surface is supported by the second supporting fixture, angular pins are provided on the second supporting fixture corresponding to the angular holes to align the outer circle of the mounting edge.

8. The method for processing an aircraft engine flame tube assembly according to claim 7, characterized in that: Before step S700, the step of polishing the parts is also included to remove burrs and flash generated by machining, so as to avoid redundant materials in the air film holes and the annular grooves.

9. The method for processing an aircraft engine flame tube assembly according to claim 8, characterized in that: Before step S700, a fluorescent inspection step is also included to perform a fluorescent inspection on the installation edge and the air film hole to eliminate crack defects.

10. The method for processing an aircraft engine flame tube assembly according to claim 1, characterized in that: After step S900, the following steps are also included: Remove splash and burrs from air film holes: Remove splash and burrs from air film holes by flushing the cooling holes with water as the medium and applying pressure. Perform a light-transmitting inspection on all holes to remove any excess material that may be present in the holes.

Images