Spliced ​​variable profile electrode, system and method for electrochemical machining of blade disks

Abstract

The present invention discloses a spliced ​​variable-profile electrode, system, and method for electrochemical machining of bladed disks, relating to the field of electrochemical machining technology. The spliced ​​variable-profile electrode for electrochemical machining of bladed disks comprises: multiple tube electrode assemblies, each hingedly connected in sequence, each having an electrolyte channel, and each having a liquid inlet and outlet connected to the electrolyte channel. In operation, any two adjacent tube electrode assemblies can rotate relative to each other so that the overall profile of the multiple tube electrode assemblies matches the cross-sectional profile of the blade channel to be machined. The present invention can meet the machining requirements of fan disk blade channels with twisted and complex surfaces.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic machining, and in particular to a spliced ​​variable profile electrode, system and method for electrolytic machining of a blade disk. Background Art

[0002] As a core component of an aircraft engine, the efficient and high-quality manufacturing method of the integral blade disk has become a key technology in the research and development of aircraft engines. With the continuous improvement of the thrust-to-weight ratio of aircraft engines, the material of the integral blade disk has gradually developed towards high strength, high hardness, and high temperature resistance of nickel-based high-temperature alloys and titanium alloys, making the processing of the integral blade disk a major problem in the manufacturing industry. Especially for large fan disks, the blade length is 100mm-300mm, and the blades are thin, highly twisted, and the flow channel is narrow. Electrolytic machining is a process method based on the principle of anodic dissolution of metal in an electrolyte to achieve material removal. Compared with traditional CNC milling, it has the characteristics of high processing efficiency, no tool wear, no influence on the mechanical properties of the material, and no residual stress. With these unique advantages, electrolytic machining has become one of the key processing methods for integral blade disks.

[0003] CNC electrochemical machining (ECM) technology uses three-dimensional motion between a rod electrode and the workpiece according to computer numerical control (CNC) instructions to electrochemically machine various complex surfaces. Therefore, CNC ECM combines the advantages of both electrochemical machining and CNC machining. However, existing CNC ECM processes generally use fixed-shaped electrodes. In this mode, the electrode's motion trajectory is a straight-line developable surface, making it unsuitable for machining the complex, twisted surfaces of fan disk blade cascade channels. Summary of the Invention

[0004] The purpose of the present invention is to provide a spliced ​​variable profile electrode, system and method for electrochemical machining of blade disks to solve the problems existing in the above-mentioned prior art and meet the processing requirements of fan disk blade channels with twisted and complex surfaces.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a spliced ​​variable-profile electrode for electrochemical machining of blade disks, comprising: a plurality of tube electrode assemblies, wherein the plurality of tube electrode assemblies are hingedly connected in sequence, each of the tube electrode assemblies having an electrolyte channel, and a liquid inlet and a liquid outlet connected to the electrolyte channel are provided on the tube electrode assembly. In a working state, any two adjacent tube electrode assemblies can rotate relative to each other so that the overall profile of the plurality of tube electrode assemblies matches the cross-sectional profile of the blade channel to be machined.

[0007] Preferably, three tube electrode assemblies are provided, two of which extend along a straight line to form a first tube electrode assembly, and the remaining tube electrode assembly is in a bent structure to form a second tube electrode assembly, and one end of the two first tube electrode assemblies is hinged to the two ends of the second tube electrode assembly respectively.

[0008] Preferably, each of the tube electrode assemblies includes a base frame and a plurality of tube electrode units, wherein the plurality of base frames are sequentially connected by hinges, each of the tube electrode units has the electrolyte channel, the tube electrode unit is provided with the liquid inlet and the liquid outlet, and each of the base frames is configured with a plurality of accommodating portions, each of the accommodating portions being used to accommodate and fix one of the tube electrode units. The base frame in the first tube electrode assembly extends along a straight line, while the base frame in the second tube electrode assembly has a bent structure. The base frame is made of a conductive material, and during processing, electrical contact is maintained between the base frame and the tube electrode units.

[0009] Preferably, each of the tube-electrode units is provided with a liquid inlet and a plurality of liquid outlets, and an array of the plurality of liquid outlets is arranged on the same side of the tube-electrode unit.

[0010] Preferably, the base frame includes two supporting slats, the accommodating portion is a cylindrical structure, the two supporting slats are arranged around the accommodating portion, the inner walls of the two supporting slats used for contacting the tube electrode unit are arc surfaces, the tube electrode unit is in the shape of a circular tube, and when the tube electrode unit is installed in the accommodating portion, the outer wall of the tube electrode unit is in contact with the inner wall of the support slats.

[0011] Preferably, the liquid outlet is aligned with the gap between the two support strips.

[0012] Preferably, a limiting body is provided between any two adjacent accommodating parts, and the limiting body is fixedly connected to the two supporting strips. When the tube electrode unit is installed in the accommodating part, both ends of the tube electrode unit are in contact with the limiting body.

[0013] Preferably, the tube electrode unit is clamped, bonded or fastened in the accommodation portion.

[0014] The present invention also provides a blade disc electrochemical machining system, comprising an electrolyte injection device, a power supply, a drive device and the spliced ​​variable profile electrode for blade disc electrochemical machining as described above; the electrolyte injection device is connected to the liquid inlet, the anode of the power supply is used to conduct with the workpiece, the cathode of the power supply is conducted with the tube electrode assembly, the drive device is used to drive the workpiece to rotate, the drive device is used to drive multiple tube electrode assemblies to rotate relative to each other to change the overall profile of the spliced ​​variable profile electrode for blade disc electrochemical machining, and the drive device is used to drive the tube electrode assembly to feed along the axial direction of the blade disc.

[0015] The present invention also provides a method for electrolytic machining of a blade disk. During the machining process, a driving device simultaneously drives the spliced ​​variable profile electrode to feed downward, drives the blade disk workpiece to move around its own axis, and drives multiple tube electrode assemblies to rotate relative to each other.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The spliced ​​variable profile electrode proposed in the present invention can control the relative rotation of multiple tube electrode assemblies during sweeping electrolytic machining of blade channels, so that the channel profile formed by electrolytic molding is closer to the actual blade profile, realizing controllable deformation of the electrode, and can meet the machining requirements of fan disk blade channels with twisted and complex surfaces, thereby improving machining accuracy.

[0018] The present invention utilizes discrete tube electrode units mounted on a base frame. These units can be modularly installed and adjusted to meet the needs of different bladed disc cascade channels, facilitating flexible replacement. Each tube electrode unit is independently supplied with electrolyte, significantly shortening the electrolyte flow. Simply ensuring uniform electrolyte output from a single tube electrode unit ensures the stability of the entire tool electrode during bladed disc channel machining.

[0019] The present invention utilizes a CNC-sweep electrolytic cutting process. After machining, the remaining material in the cascade channels is removed from the blisk substrate for subsequent reuse. Furthermore, material removal during CNC-sweep electrolytic machining is limited to a small area within the electrode structure, reducing the total machining current and the discharge of electrolytic products, improving the environmental friendliness of the process and ultimately achieving efficient and cost-effective CNC electrolytic machining of blisks. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1Schematic diagram of a spliced ​​variable profile electrode for electrochemical machining of a blade disk provided in an embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the base frame assembly.

[0023] Figure 3 Schematic diagram of the first base frame.

[0024] Figure 4 Schematic diagram of the second base frame.

[0025] Figure 5 Schematic diagram of the tube electrode unit.

[0026] Figure 6 For use Figure 1 Schematic diagram of the machining of an integral blade disk by electrochemical machining using a spliced ​​variable profile electrode.

[0027] Figure 7 for Figure 6 Schematic diagram of the initial and final states of the material head and the spliced ​​variable profile electrode;

[0028] Figure 8 for Figure 7 Middle, schematic diagram of the final state of the spliced ​​variable profile electrode;

[0029] Figure 9 for Figure 7 Schematic diagram of the deformation process of the spliced ​​variable profile electrode.

[0030] In the figure: 1-first base frame; 2-hinge; 3-second base frame; 6-tube electrode unit; 11-supporting strip; 12-limiting body; 13-gap; 14-connecting column head; 61-liquid inlet; 62-liquid outlet; 100-spliced ​​variable profile electrode; 200-material head; 300-integral blade disk. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] The following combination Figures 1 to 9 , describing embodiments of the present invention.

[0034] The present invention provides a spliced ​​variable profile electrode 100 for electrochemical machining of a blade disk, which is suitable for CNC electrochemical machining, such as Figures 1 to 5 As shown, it includes: multiple tube electrode assemblies, the multiple tube electrode assemblies are hinged in sequence, each tube electrode assembly has an electrolyte channel, and the tube electrode assembly is provided with a liquid inlet 61 and a liquid outlet 62 connected to the electrolyte channel. In the working state, any two adjacent tube electrode assemblies can rotate relative to each other so that the overall profile of the multiple tube electrode assemblies matches the cross-sectional profile of the blade channel to be processed. The matching here refers to the overall profile of the multiple tube electrode assemblies being exactly the same or approximately the same as the cross-sectional profile of the blade channel to be processed, and being exactly the same in size, or the overall profile of the multiple tube electrode assemblies being slightly smaller than the cross-sectional profile of the blade channel to be processed.

[0035] In the working state, the liquid outlet 62 is aligned with the part to be electrolytically corroded.

[0036] The spliced ​​variable profile electrode 100 proposed in the present invention can control the relative rotation of multiple tube electrode assemblies when performing sweeping electrolytic machining of blade channels, so that the channel profile formed by electrolytic molding is closer to the actual blade surface, realizing controllable deformation of the electrode, and being able to meet the machining requirements of fan disk blade channels with twisted and complex surfaces, thereby improving machining accuracy.

[0037] Furthermore, the present invention enables sweeping electrochemical cutting. After machining is complete, the slug 200 in the cascade channel is removed from the blisk substrate for subsequent reuse. Furthermore, material removal during cutting-type CNC electrochemical machining is limited to a small area within the electrode structure, reducing the total machining current and the discharge of electrolytic products, improving the process's environmental friendliness and ultimately achieving efficient and cost-effective CNC electrochemical machining of blisks.

[0038] In some embodiments, the present invention is provided with three tube electrode assemblies, two of which extend along a straight line as a first tube electrode assembly, and the remaining tube electrode assembly has a bent structure as a second tube electrode assembly, and one end of the two first tube electrode assemblies is hinged to the two ends of the second tube electrode assembly respectively.

[0039] The overall profile of the three tube electrode assemblies in this embodiment is approximately a "U"-shaped structure. This embodiment makes the profile of the spliced ​​variable profile electrode 100 roughly the same as the cross-sectional profile of the blade channel to be processed. In addition, only three tube electrode assemblies are provided to facilitate the control of the relative movement between the three tube electrode assemblies. In other words, if more than three tube electrode assemblies are provided, for example five, the relative movement between the five tube electrode assemblies will be difficult to accurately control.

[0040] In the related art, when CNC electrolytic machining of integral blade disks is used, an internal spray-type liquid outlet is usually adopted. The electrolyte enters from one end of the rod electrode and is sprayed from the liquid outlet on the side wall to hit the surface of the workpiece and then "flips" up from both sides of the electrode. However, this will bring a problem. For the machining of fan disk parts with blade lengths exceeding 200mm, the material removal rate is large and the electrolyte flow is too long, resulting in an increase in the electrolyte flow rate loss in the machining gap. This affects the consistency and stability of the entire machining gap and limits the improvement of the machining speed. What is more serious is that the lack of local electrolyte may cause the machining state to be unstable, or even cause a short circuit, damaging the electrode and the workpiece. Based on this, the present invention solves the above problems through the following embodiments.

[0041] In some embodiments, each tube electrode assembly includes a base frame and multiple tube electrode units 6. The multiple base frames are connected in sequence by hinges 2. Each base frame is constructed with multiple accommodating portions, each of which is used to accommodate and fix a tube electrode unit 6. The base frame in the first tube electrode assembly extends along a straight line, and the base frame in the second tube electrode assembly has a bent structure. The base frame is made of a conductive material. During the processing, the base frame maintains electrical contact with the tube electrode unit 6. It can be understood that the tube electrode unit 6 is a hollow tube structure with both axial ends closed and a liquid inlet 61 and a liquid outlet 62 provided on its side.

[0042] This embodiment uses a base frame to securely support multiple tube electrode units 6, enabling a discrete arrangement of the tube electrode units 6. This allows modular installation and adjustment of the discreteness, or quantity and density, of the tube electrode units 6 based on the requirements of different bladed disk cascade channels, thereby better meeting machining requirements. Furthermore, each tube electrode unit 6 is independently supplied with electrolyte, significantly shortening the electrolyte flow. Simply ensuring uniform electrolyte output from a single tube electrode unit 6 ensures the stability of the entire tool electrode during cascade channel machining.

[0043] In addition, the purpose of energizing all tube electrode units 6 can be achieved by simply energizing the base frame, which simplifies circuit layout.

[0044] Description, such as Figures 1 to 4 As shown, the base frame in the first tube-electrode assembly is the first base frame 1 , and the base frame in the second tube-electrode assembly is the second base frame 3 .

[0045] In some examples, grooves are respectively configured at both ends of the hinge 2 , and a connecting column head 14 is configured at the end of the base frame for connecting to the hinge 2 .

[0046] In some embodiments, each tube electrode unit 6 is provided with a liquid inlet 61 and a plurality of liquid outlets 62 , and the plurality of liquid outlets 62 are arranged in an array on the same side of the tube electrode unit 6 .

[0047] The liquid outlets 62 in this embodiment may also be referred to as liquid outlet slits, which are sequentially arranged along a straight line on the tube electrode unit 6 .

[0048] The structure and distribution of the liquid outlet slits in this embodiment are designed based on fluid mechanics and finite element simulation, which can ensure the uniformity of electrolyte flow within the length of the tube electrode unit 6.

[0049] In some embodiments, the base frame includes two support strips 11, the accommodating portion is a cylindrical structure, the two support strips 11 are arranged around the accommodating portion, the inner walls of the two support strips 11 used for contacting the tube electrode unit 6 are arc surfaces, the tube electrode unit 6 is in the shape of a circular tube, and when the tube electrode unit 6 is installed in the accommodating portion, the outer wall of the tube electrode unit 6 is in contact with the inner wall of the support strips 11. In some examples, the liquid outlet 62 is aligned with the gap 13 between the two support strips 11 to ensure that the electrolyte is sprayed from the side wall of the tube electrode unit 6 into the processing gap.

[0050] The two support strips 11 in this embodiment serve the purpose of supporting the tube electrode unit 6 .

[0051] In some embodiments, a limiting body 12 is provided between any two adjacent accommodating portions. The limiting body 12 is fixedly connected to the two supporting strips 11 . When the tube electrode unit 6 is installed in the accommodating portion, both ends of the tube electrode unit 6 are in contact with the limiting body 12 .

[0052] The limiting body 12 in this embodiment is used to limit the axial movement of the tube electrode unit 6 on its side, so that each accommodating portion is independently provided, thereby realizing the discrete arrangement of the tube electrode units 6 and the adjustment of the number of the tube electrode units 6 .

[0053] In some embodiments, the tube electrode unit 6 is clipped, bonded, or fastened into the receiving portion.

[0054] This embodiment provides several ways to fix the tube electrode units 6. Since the number of tube electrode units 6 needs to be adjusted in some scenarios, the tube electrode units 6 are preferably detachably connected in the accommodation portion. The connection method can be snap connection, strapping, etc.

[0055] The present invention also provides a blade disk electrochemical machining system, which can perform CNC electrochemical machining, such as Figure 6 As shown, it includes an electrolyte injection device, a power supply, a driving device and the spliced ​​variable profile electrode 100 for electrochemical machining of the blade disk as described above; the electrolyte injection device is connected to the liquid inlet 61, the anode of the power supply is used to conduct with the workpiece, the cathode of the power supply is connected with the tube electrode assembly, the driving device is used to drive the workpiece to rotate, the driving device is used to drive multiple tube electrode assemblies to rotate relative to each other to change the overall profile of the spliced ​​variable profile electrode 100 for electrochemical machining of the blade disk, and the driving device is used to drive the tube electrode assembly to feed along the axial direction of the blade disk.

[0056] This embodiment has all the advantages of the above embodiments, which will not be described in detail here.

[0057] The present invention also provides a method for electrochemical machining of a blade disk, specifically a method for electrochemical machining of a numerically controlled blade disk, such as Figures 6 to 9 As shown, the above-mentioned blade disk electrochemical machining system is used for machining. During the machining process, the driving device simultaneously drives the spliced ​​variable profile electrode 100 to feed downward, drives the blade disk workpiece to move around its own axis, and drives multiple tube electrode assemblies to rotate relative to each other.

[0058] Specifically, during CNC electrochemical machining of the integral blade disk 300, an electrolyte injection device delivers an equal flow of electrolyte to each tube electrode unit 6. The blade disk workpiece is connected to the positive terminal of the power supply, while the base frame is connected to the negative terminal of the power supply. A drive device drives the base frame, which in turn drives the tube electrode units 6 downward, while simultaneously driving the blade disk workpiece around its own axis. This two-axis, three-dimensional motion achieves blade channel machining. During the downward feed of the base frame, the two first tube electrode assemblies are controlled to rotate the hinge 2 a certain angle to deform the overall electrode profile, making the channel profile more closely match the actual blade profile. During machining, electrical contact is maintained between the base frame and the tube electrode units 6.

[0059] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A spliced ​​variable profile electrode for electrochemical machining of a blade disk, characterized by: include: A plurality of tube electrode assemblies, the plurality of tube electrode assemblies being hinged in sequence, each of the tube electrode assemblies having an electrolyte channel, and a liquid inlet and a liquid outlet communicating with the electrolyte channel being formed on the tube electrode assemblies. In a working state, any two adjacent tube electrode assemblies can rotate relative to each other so that the overall profile of the plurality of tube electrode assemblies matches the cross-sectional profile of the blade channel to be machined. Three tube electrode assemblies are provided, two of which extend in a straight line as first tube electrode assemblies, and the remaining tube electrode assembly has a bent structure as a second tube electrode assembly, and one end of the two first tube electrode assemblies is hinged to the two ends of the second tube electrode assembly respectively. Each tube electrode assembly includes a base frame and multiple tube electrode units. Each tube electrode unit has the electrolyte channel. The tube electrode unit is provided with the liquid inlet and the liquid outlet. The multiple base frames are connected in sequence by hinges. Each base frame is constructed with multiple accommodating portions, each of which is used to accommodate and fix one tube electrode unit. The base frame in the first tube electrode assembly extends along a straight line, while the base frame in the second tube electrode assembly has a bent structure. The base frame is made of conductive material. During the processing, the base frame maintains electrical contact with the tube electrode unit.

2. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 1, characterized in that: Each tube-electrode unit is provided with a liquid inlet and a plurality of liquid outlets, and an array of the plurality of liquid outlets is arranged on the same side of the tube-electrode unit.

3. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 1, characterized in that: The base frame includes two supporting slats, the accommodating portion is a cylindrical structure, the two supporting slats are arranged around the accommodating portion, the inner walls of the two supporting slats used for contacting the tube electrode unit are arc surfaces, the tube electrode unit is in the shape of a circular tube, and when the tube electrode unit is installed in the accommodating portion, the outer wall of the tube electrode unit contacts the inner wall of the supporting slats.

4. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 3, characterized in that: The liquid outlet is aligned with the gap between the two supporting strips.

5. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 3, characterized in that: A limiting body is provided between any two adjacent accommodating parts, and the limiting body is fixedly connected to the two supporting strips. When the tube electrode unit is installed in the accommodating part, both ends of the tube electrode unit are in contact with the limiting body.

6. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 1, characterized in that: The tube electrode unit is clamped, bonded or fastened in the accommodation portion.

7. A blisk electrochemical machining system, characterized by: It comprises an electrolyte injection device, a power supply, a drive device and a spliced ​​variable profile electrode for electrochemical machining of a blade disk according to any one of claims 1 to 6; the electrolyte injection device is connected to the liquid inlet, the anode of the power supply is used to conduct with the workpiece, the cathode of the power supply is conducted with the tube electrode assembly, the drive device is used to drive the workpiece to rotate, the drive device is used to drive multiple tube electrode assemblies to rotate relative to each other to change the overall profile of the spliced ​​variable profile electrode for electrochemical machining of a blade disk, and the drive device is used to drive the tube electrode assembly to feed along the axial direction of the blade disk.

8. A method for electrochemical machining of a blade disk, characterized by: The blade disk electrochemical machining system according to claim 7 is used for machining. During the machining process, the driving device simultaneously drives the spliced ​​variable profile electrode to feed downward, drives the blade disk workpiece to move around its own axis, and drives multiple tube electrode assemblies to rotate relative to each other.

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