Post-welding processing method for high-pressure turbine disk welding assembly

Abstract

This invention provides a post-weld processing method for high-pressure turbine disk welded assemblies, which can be used to process high-pressure turbine disk welded assemblies connected by friction welding, resulting in high-precision parts. The method includes the following steps: dimensional re-inspection; weld turning; first weld defect inspection; vacuum heat treatment; second weld defect inspection; datum repair; semi-finish turning; finish turning; tenon groove drawing; tenon groove rounding; milling; first fluorescent penetrant testing; shot peening; mating surface repair; dimensional inspection; dynamic balancing test; second fluorescent penetrant testing; and final inspection.

Description

Technical Field

[0001] This invention relates to the field of post-weld processing technology for turbine disk welding assemblies, specifically to a post-weld processing method for high-pressure turbine disk welding assemblies. Background Technology

[0002] like Figure 1 The high-pressure turbine disk assembly of an aero-engine typically includes a rear shaft 101, a turbine disk 102, and a drum shaft 103. The rear shaft and drum shaft are cylindrical. Previously, these three components were connected using bolts, but this method is complex to install, has low connection strength, and increases the engine's weight, thus affecting performance. Therefore, to improve engine performance and optimize component connections, inertial friction welding is used to connect the individual high-pressure turbine disks, forming an assembly. This significantly reduces the assembly's weight and improves engine performance. However, current inertial friction welding cannot meet the required precision for welding large components. Therefore, a solution is needed where each disk has full allowance before welding, and the assembly is machined to full dimensions after welding. High-pressure turbine disk assemblies are generally welded from high-temperature alloys and powder metallurgy materials, resulting in high material hardness. The assembled assembly has a complex shape, and the high dimensional accuracy requirements, coupled with the fact that post-weld machining easily leads to deformation and dimensional deviations, makes machining extremely difficult. Therefore, it is necessary to develop post-weld machining methods specifically tailored to the structural characteristics and technological challenges of high-pressure turbine disk welded assemblies. Summary of the Invention

[0003] To address the challenges of post-weld processing of high-pressure turbine disk assemblies welded by friction welding, including difficulties in part deformation and ensuring high dimensional accuracy, this invention provides a post-weld processing method for high-pressure turbine disk assemblies. This method can be used to process high-pressure turbine disk assemblies welded together by friction welding, resulting in high-precision parts.

[0004] The technical solution is as follows: a post-weld processing method for high-pressure turbine disk welding assembly, characterized by the following steps: 1. Dimension re-inspection process; measuring the high-pressure turbine disk welding assembly in which the rear axle, turbine disk and drum shaft are welded together sequentially by inertial friction welding, and obtaining data including the welding dimension accuracy of the parts and the deformation of the parts, as indicators for subsequent processing;

[0005] 2. Welding process; removing welding burrs from the inner and outer surfaces of the parts;

[0006] 3. First weld defect inspection procedure: Weld internal defects are detected by ultrasonic testing, and weld surface defects are detected by fluorescent penetrant testing.

[0007] 4. Vacuum heat treatment process: Vacuum heat treatment is performed on qualified parts to eliminate thermal stress in the welding area of ​​the parts;

[0008] 5. Second weld defect inspection process: The weld defects caused by vacuum heat treatment are detected again by ultrasonic testing and fluorescent penetrant testing. Parts that pass the inspection proceed to the next process.

[0009] 6. Repair the reference process; machine a flat surface on the surface of the high-pressure turbine disk welding assembly as the machining reference for subsequent semi-finish turning and finish turning processes;

[0010] 7. Semi-finish turning process; machining the surface of the part, leaving a allowance a;

[0011] 8. Finishing process; finish machining the parts, leaving a margin b for the positions with dimensional tolerances within 0.05mm, the outer circle of the turbine disk, and the inner diameter of the drum shaft mounting edge. The margin b is less than the margin a. For other positions, remove the reserved margin a and make the dimensions meet the target size requirements.

[0012] 9. Tenoning process: After the part passes the broaching test, the tenon groove of the part is broached.

[0013] 10. Round the tenon; after broaching, round the sharp edges on both sides of the tenon.

[0014] 11. Milling process; Milling is used to process the tenons, bolt holes, and splines of the parts;

[0015] 12. First fluorescent penetrant testing process; Fluorescent penetrant testing is performed on the surface of the parts;

[0016] 13. Shot peening process; shot peening treatment of the surface of the parts;

[0017] 14. Repairing mating surfaces: Remove the allowance reserved in step 8 and make the dimensions meet the requirements;

[0018] 15. Dimension Inspection Process: Use a coordinate measuring machine (CMM) to inspect the dimensions of the parts and confirm that all dimensions meet the design requirements. If not, continue to adjust until all dimensions meet the requirements.

[0019] 16. Dynamic balancing process;

[0020] 17. Second fluorescent penetrant testing process: Perform fluorescent penetrant testing on the processed areas of the parts after shot peening to confirm that there are no defects on the surface;

[0021] 18. Final inspection process: Clean and package the parts that fully meet the design requirements and put them into storage.

[0022] Its further features are:

[0023] The welding dimensional accuracy and deformation of the parts mentioned in step 1 include the total axial length of the parts, the axial dimensions on both sides of the weld, and the radial runout and planar runout of the parts at the weld.

[0024] In step 7, the allowance a is 0.5mm; in step 8, the allowance b is 0.1-0.2mm.

[0025] In step 8, the allowance reserved on the outer circle of the turbine disk is 0.15mm;

[0026] In step 8, a 0.1mm allowance is reserved at the inner diameter of the drum shaft mounting edge;

[0027] In step 9, the part is broached using a broaching fixture. The broaching fixture includes a base, which is hollow to accommodate the rear axle and has a side wall on its outer side. A support ring is connected to the top of the side wall to support one side of the turbine disk. A cover plate is also pressed onto the other side of the turbine disk. The cover plate is hollow to accommodate the drum shaft. A positioning center shaft is connected inside the base. The positioning center shaft passes through the rear axle, the turbine disk, and the drum shaft, extends out of the cover plate, and is connected to a clamping bolt. The clamping bolt is pressed onto the cover plate. The cover plate and the side wall of the base are provided with weight reduction grooves.

[0028] In step 16, a dynamic balancing test is conducted using a dynamic balancing fixture. Before the test, the fixture is balanced to eliminate the influence of the fixture's imbalance.

[0029] The beneficial effects of this invention are as follows: By performing post-weld processing on the high-pressure turbine disk welding assembly obtained by inertial friction welding in the above manner, the machining accuracy of the parts can be effectively guaranteed. In particular, after the first inspection of weld defects, the vacuum heat treatment process can not only eliminate thermal stress but also amplify the microcracks in the uninspected areas. Thus, the second weld defect inspection can effectively detect defects at the weld, avoiding the impact of weld defects on product quality. Before semi-finish turning and finish turning parts, a reference plane is processed by a reference repair process, which can avoid the deformation of the parts after heat treatment from affecting the machining positioning. In the finish turning process, by pre-leaving a certain position, the subsequent processing can avoid deformation of the parts, which would lead to dimensional deviations. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the high-pressure turbine disk assembly structure;

[0031] Figure 2 This is a cross-sectional schematic diagram of the component after inertial friction welding.

[0032] Figure 3 This is a cross-sectional view of a component part during the semi-finish machining process;

[0033] Figure 4 This is a schematic diagram of the broaching tooling structure;

[0034] Figure 5This is a schematic diagram of the installation structure of welding components in the dynamic balancing process. Detailed Implementation

[0035] Before friction welding, the assembly process involves collecting the corresponding sub-components according to the component drawing requirements, recording the product information of each sub-component for future traceability; confirming that the dimensions of the sub-components meet the pre-welding requirements, and verifying the surface quality for defects such as pits and dents. Then, the parts are subjected to inertial friction welding through the welding process. The welded assembly is shown below. Figure 2 As shown ( Figure 2 (This is a cross-sectional view of the upper half of the welded assembly). Point A in the figure is the weld location, and the part that needs to be machined is the target shape.

[0036] After completing the above welding, the post-weld processing method of the high-pressure turbine disk welding assembly is carried out, which includes the following steps: 1. Dimensional re-inspection process; Measure the high-pressure turbine disk welding assembly in which the rear axle, turbine disk and drum shaft are welded together in sequence by inertial friction welding, and obtain data including the welding dimensional accuracy of the parts and the deformation of the parts. Specifically, consider the total axial length of the parts, the axial dimensions on both sides of the weld, and the radial runout and planar runout of the parts at the weld. These dimensions are important indicators that will affect whether the parts meet the subsequent processing requirements.

[0037] 2. Welding process: Remove welding burrs from the inner and outer surfaces of the parts to ensure the feasibility of subsequent non-destructive inspection of the parts; generally, only the area around the weld needs to be machined to make the surface of the parts smooth and flat.

[0038] 3. First weld defect inspection procedure: Ultrasonic testing is used to detect internal weld defects, and fluorescent penetrant testing is used to detect surface weld defects. Ultrasonic testing is used to check for defects such as bubbles and cracks inside the weld, while fluorescent penetrant testing is used to confirm whether there are defects such as cracks on the surface and near the surface. Only after the above results are qualified can the next procedure be carried out.

[0039] 4. Vacuum heat treatment process: Vacuum heat treatment is performed on qualified parts to eliminate thermal stress in the welding area and adjust the forging state of the parts.

[0040] 5. Second weld defect inspection process: The weld defects that have been extended or expanded due to vacuum heat treatment are detected again by ultrasonic testing and fluorescent penetrant testing. (For example, some microcracks may extend or expand due to heat treatment, which may lead to weld fracture in severe cases.) Parts that pass the inspection will proceed to the next process.

[0041] 6. Repair the reference process; Due to the deformation of the parts after heat treatment, a flat surface needs to be machined on the surface of the high-pressure turbine disk welding assembly as the machining reference for the subsequent semi-finish turning and finish turning processes.

[0042] 7. Semi-finish turning process: Machining the surface of the part with a uniform allowance of 0.5mm. All surfaces, including grooves and bosses, must be machined to eliminate previous deformation and avoid excessive deformation during finish turning. The finished product should look like... Figure 3 As shown.

[0043] 8. Finishing process; finish machining the part dimensions, remove all the allowance reserved in the previous step, and process to the size required by the design drawing; considering that there will still be machining process in the future, which may cause deformation of the part and cause the size to exceed the tolerance, during finishing, an additional allowance of 0.1~0.2mm is required for some positions, and the final machining is completed; the specific allowance positions are as follows: (1) positions with high dimensional accuracy and dimensional tolerance within 0.05mm; (2) the outer circle of the turbine disk is greatly deformed due to the broaching effect, and an additional allowance of 0.15mm is required on one side; (3) the inner diameter of the drum shaft mounting edge, since the edge needs to be milled later, which will affect the size, an allowance of 0.1mm is required on one side at the inner diameter.

[0044] 9. Tenoning process; After the part passes the broaching test, the tenon groove of the part is ( Figure 1 The tenon groove 104) is broached. Before machining, broaching fixtures, broaches, broaching test pieces, etc. need to be prepared. When designing the broaching fixture, its own weight should be reduced as much as possible. Weight-reducing grooves are added to the fixture to reduce weight while ensuring the rigidity of the fixture, thereby reducing the torque borne by the indexing plate in the vertical direction during broaching. Specific broaching fixtures are as follows: Figure 4 As shown, the broaching fixture includes a base 1, which is hollow to accommodate the rear shaft 101 and has a side wall 2 on its outer side. A support ring 3 is connected to the top of the side wall 2 to support one side of the turbine disk 102. A cover plate 4 is also pressed on the other side of the turbine disk 102. The cover plate 4 is hollow to accommodate the drum shaft 103. A positioning center shaft 5 is connected inside the base 1. The positioning center shaft 5 passes through the rear shaft 101, the turbine disk 102, and the drum shaft 103, and extends out of the cover plate 4 and is connected to a clamping bolt 6. The clamping bolt 6 is pressed on the cover plate 4. The cover plate 4 and the side wall of the base 1 are provided with weight reduction grooves 7. Before broaching the formal part, a broaching test needs to be carried out. Only after all test results are qualified can the formal part be broached.

[0045] 10. Rounding the tenon: After broaching, round the sharp edges on both sides of the tenon and mark them on the part body according to the design drawings.

[0046] 11. Milling process; The tenon, bolt hole and spline of the part are processed by milling; Several points need to be noted: (1) Pay attention to the angular position of the first groove and the first hole. Since the tenon is processed first, the first groove is aligned on the machine tool as the angular reference; (2) For precision bolt hole processing, pay attention to drilling first, then milling the edge, and finally finishing the hole to ensure the position of the hole of the part; (3) For spline processing, a spline test piece needs to be designed in advance; the formal part can be processed only after the test is qualified.

[0047] 12. First fluorescent penetrant testing process: Perform fluorescent penetrant testing on the surface of the part to confirm that there are no defects on the surface before proceeding to the next step.

[0048] 13. Shot peening process: Shot peening is performed on the surface of the parts.

[0049] 14. Repairing mating surfaces: Remove the allowance reserved in step 8 and make the dimensions meet the requirements; the outer circle of the turbine disk is ground; measurements are taken before and after machining to ensure the final dimensional requirements; the remaining surfaces are machined on a lathe, and many dimensional accuracy is high, requiring multiple people to measure and confirm during machining.

[0050] 15. Dimension Inspection Process: Use a coordinate measuring machine (CMM) to inspect the dimensions of the parts and confirm whether all dimensions meet the design requirements. If not, continue to adjust until all dimensions meet the requirements.

[0051] 16. Dynamic balancing process: Perform dynamic balancing on the parts according to the design drawings, and fix the rear axle as follows: Figure 5 On the rotating device 8 shown, the belt drives the rotating device 8 parts to rotate, ensuring that the rotation speed is 800-1200 (rpm). The key position of the part is measured, and the imbalance generated by the part during the processing is eliminated by local clamping and grinding at the key position of the part. This ensures that the part will not have an eccentric torque when rotating around the rotation center. Dynamic balancing points: (1) Before dynamic balancing of the part, the fixture needs to be balanced to eliminate the influence of the fixture imbalance. Generally, the dynamic balancing fixture of high vortex uses static balancing to eliminate the imbalance. Therefore, it is necessary to design another set of static balancing fixtures to provide dynamic balancing tooling. (2) It is important to clearly define in the process that the mounting surface of the part is protected to avoid the dynamic balancing equipment from scratching, indenting, etc. on the surface of the part.

[0052] 17. Second fluorescent penetrant testing process: Perform fluorescent penetrant testing on the processed areas of the parts after shot peening to confirm that there are no defects on the surface.

[0053] 18. Final inspection process: After confirming that there are no problems with the actual parts and quality data, the parts that fully meet the design requirements are cleaned, packaged and put into storage.

[0054] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A post-weld processing method for a high-pressure turbine disk welding assembly, characterized in that, It includes the following steps:

1. Dimensional verification process: Measure the high-pressure turbine disk welding assembly, in which the rear axle, turbine disk, and drum shaft are welded together sequentially by inertial friction welding, and obtain data including the welding dimensional accuracy and deformation of the parts, as indicators for subsequent processing.

2. Welding process; removing welding burrs from the inner and outer surfaces of the parts; 3. First weld defect inspection procedure: Weld internal defects are detected by ultrasonic testing, and weld surface defects are detected by fluorescent penetrant testing.

4. Vacuum heat treatment process: Vacuum heat treatment is performed on qualified parts to eliminate thermal stress in the welding area of ​​the parts; 5. Second weld defect inspection process: The weld defects caused by vacuum heat treatment are detected again by ultrasonic testing and fluorescent penetrant testing. Parts that pass the inspection proceed to the next process.

6. Repair the reference process; Due to the deformation of the parts after heat treatment, a flat surface is machined on the surface of the high-pressure turbine disk welding assembly as the machining reference for the subsequent semi-finish turning and finish turning processes.

7. Semi-finish turning process; machining the surface of the part, leaving a allowance a; All surfaces, including grooves and bosses, are machined to eliminate any previous deformation of the parts.

8. Finishing process; finish machining the parts, leaving a margin b for the positions with dimensional tolerances within 0.05mm, the outer circle of the turbine disk, and the inner diameter of the drum shaft mounting edge. The margin b is less than the margin a. For other positions, remove the reserved margin a and make the dimensions meet the target size requirements.

9. Tenoning process: After the part passes the broaching test, the tenon groove of the part is broached. In step 9, the part is broached using a broaching fixture. The broaching fixture includes a base, which is hollow to accommodate the rear axle and has side walls on its outer side. A support ring is connected to the top of the side walls to support one side of the turbine disk. A cover plate is also pressed onto the other side of the turbine disk. The cover plate is hollow to accommodate the drum shaft. A positioning center shaft is connected inside the base. The positioning center shaft passes through the rear axle, the turbine disk, and the drum shaft, extends out of the cover plate, and is connected to a clamping bolt. The clamping bolt is pressed onto the cover plate. The cover plate and the side walls of the base are provided with weight-reducing grooves. The weight-reducing grooves reduce the torque borne by the indexing plate in the vertical direction during broaching.

10. Round the tenon; after broaching, round the sharp edges on both sides of the tenon.

11. Milling process; Milling is used to process the tenons, bolt holes, and splines of the parts; 12. First fluorescent penetrant testing process; Fluorescent penetrant testing is performed on the surface of the parts; 13. Shot peening process; shot peening treatment of the surface of the parts; 14. Repairing mating surfaces: Remove the allowance reserved in step 8 and make the dimensions meet the requirements; 15. Dimension Inspection Process: Use a coordinate measuring machine (CMM) to inspect the dimensions of the parts and confirm that all dimensions meet the design requirements. If not, continue to adjust until all dimensions meet the requirements.

16. Dynamic balancing process; The rear axle is fixed to the rotating device, and the belt drives the rotating device parts to rotate. The key positions of the parts are measured, and the imbalance generated during the processing of the parts is eliminated by local clamping and grinding at the key positions of the parts to ensure that there is no eccentric torque when the parts rotate around the center of rotation. The mounting surface of the parts is protected during the dynamic balancing process.

17. Second fluorescent penetrant testing process: Perform fluorescent penetrant testing on the processed areas of the parts after shot peening to confirm that there are no defects on the surface; 18. Final inspection process: Clean and package the parts that fully meet the design requirements and put them into storage.

2. The post-weld processing method for the high-pressure turbine disk welding assembly according to claim 1, characterized in that: The welding dimensional accuracy and deformation of the parts mentioned in step 1 include the total axial length of the parts, the axial dimensions on both sides of the weld, and the radial runout and planar runout of the parts at the weld.

3. The post-weld processing method for the high-pressure turbine disk welding assembly according to claim 1, characterized in that: In step 7, the allowance a is 0.5mm; in step 8, the allowance b is 0.1-0.2mm.

4. The post-weld processing method for the high-pressure turbine disk welding assembly according to claim 3, characterized in that: In step 8, the allowance reserved on the outer circle of the turbine disk is 0.15mm.

5. The post-weld processing method for the high-pressure turbine disk welding assembly according to claim 3 or 4, characterized in that: In step 8, a 0.1mm allowance is reserved at the inner diameter of the drum shaft mounting edge.

6. The post-weld processing method for the high-pressure turbine disk welding assembly according to claim 1, characterized in that: In step 16, a dynamic balancing test is conducted using a dynamic balancing fixture. Before the test, the fixture is balanced to eliminate the influence of the fixture's imbalance.

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